Pel - User contributions [en-gb]

Review:RTE

2013-04-03T19:16:42Z

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<accesscontrol>reviewer,pel</accesscontrol>
hello

Review

2013-02-13T22:29:04Z

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<accesscontrol>reviewer,pel</accesscontrol>

Review

2013-02-12T22:48:48Z

Root: Created page with "<accesscontrol>reviewer</accesscontrol>"

<accesscontrol>reviewer</accesscontrol>

REVIEW

2013-02-12T22:37:52Z

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<accesscontrol>reviewer</accesscontrol>

REVIEW

2013-02-12T22:26:14Z

Root: Created page with "<accesscontrol>review</accesscontrol>"

<accesscontrol>review</accesscontrol>

MediaWiki:Sidebar

2012-07-20T10:49:08Z

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MediaWiki:Sidebar

2012-07-17T05:52:43Z

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MediaWiki:Sidebar

2012-07-10T10:51:49Z

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MediaWiki:Sidebar

2012-07-10T10:51:32Z

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MediaWiki:Sidebar

2012-07-10T10:37:40Z

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** Main_Page|Home
**events:home|News
** people:home|People
**projects:home|Projects
**pubs:home|Publications
**partners:home|Partners
**vacancies:home|Vacancies
**valorisation:home|Valorisation
**contacts:home|Contacts

<html>
<a href="http://www.linkedin.com/groups/Connected-Vehicles-3932997" target="_blank"><img src="http://www.iccve.org/images/share/linkedin.png" alt="linkedin" /></a>
<a href="http://www.linkedin.com/groups/Connected-Vehicles-3932997" target="_blank"><img src="http://www.iccve.org/images/share/facebook.png" alt="facebook" /></a>
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</a><a href="http://www.linkedin.com/groups/Connected-Vehicles-3932997" target="_blank"><img src="http://www.iccve.org/images/share/youtube.png" alt="youtube" /></a>
<a href="http://www.linkedin.com/groups/Connected-Vehicles-3932997" target="_blank"><img src="http://www.iccve.org/images/share/rss.png" alt="rss" /></a>
</html>

MediaWiki:Sidebar

2012-05-24T17:39:01Z

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MediaWiki:Sidebar

2012-05-24T17:20:12Z

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MediaWiki:Sidebar

2012-05-24T17:19:53Z

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MediaWiki:Sidebar

2012-03-21T15:12:27Z

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Pubs:home

2012-03-10T22:02:32Z

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Partners:home

2012-03-09T15:31:38Z

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{|width="100%" align="center" cellpadding="0" cellspacing="50" border="0"
|style="width: 30%;"|[[File:Embarkinit.jpeg|150px|link=http://www.ircset.ie/]]||[http://www.ircset.ie Embark]
|-
|style="width: 50%;"|[[File:EI.jpg|150px|link=http://www.enterprise-ireland.com/]]|| [http://www.enterprise-ireland.com/ Enterprise Ireland]
|-
|style="width: 30%;"|[[File:fp7.png|150px|link=http://www.fp7ireland.com/]]||[http://www.fp7ireland.com/ FP7]
|-
|style="width: 30%;"|[[File:hea.gif|150px|link=http://www.hea.ie/]]||[http://www.hea.ie/ Higher Education Authority]
|-
|style="width: 30%;"|[[File:ibm.jpeg|150px|link=http://www.ibm.com/ie/]]|| [http://www.ibm.com/ie/ IBM Ireland]
|-
|style="width: 30%;"|[[File:lero.gif|150px|link=http://lero.ie/]]||[http://lero.ie Lero]
|-
|style="width: 30%;"|[[File:marie.jpg|150px|link=http://ec.europa.eu/research/mariecurieactions/]]||[http://ec.europa.eu/research/mariecurieactions/ Marie Curie Actions]
|-
|style="width: 30%;"|[[File:sfi.png|150px|link=http://www.sfi.ie/]]||[http://www.sfi.ie/ SFI: Science Foundation Ireland]
|}

People:home

2012-03-09T14:04:55Z

Root: /* Post-Graduate Researchers */

__NOTOC__
== Academic Staff ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.csi.ucd.ie/Staff/jmurphy/default.htm John Murphy]
| style=""| CSI/B2.22
| style=""| +353-1-716-2928
| style=""| <email>j.murphy@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| [http://www.csi.ucd.ie/staff/lmurphy/home/ Liam Murphy]
| style="background-color:#CCFFFF;"| CSI/B1.02
| style="background-color:#CCFFFF;"| +353-1-716-2914
| style="background-color:#CCFFFF;"| <email>liam.murphy@ucd.ie</email>
|-
|}

== Research Fellows ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~soufiene.djahel/ Soufiene Djahel]
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>sdjahel@gmail.com</email>
|-
| style="background-color:#CCFFFF;"| [http://performance.ucd.ie/jfitzpatrick/ John Fitzpatrick]
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>johnfitzpat@gmail.com</email>
|-
| style=""| Sean Murphy
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>Sean.Murphy@iname.com</email>
|-
| style="background-color:#CCFFFF;"| Hamid Nafaa
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>nafaa@ieee.org</email>
|-
| style=""| Dawid Nowak
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>dawid.nowak@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| Christina Thorpe
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-xxxx
| style="background-color:#CCFFFF;"| <email>christina.thorpe@gmail.com</email>
|-
| style=""| [http://aventresque.free.fr Anthony Ventresque]
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>anthony.ventresque@ucd.ie</email>
|-
|}

== Post-Graduate Researchers ==

{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| Newres AlHaider
| style=""|
|-
| style="background-color:#CCFFFF;"| Saima Arif
| style="background-color:#CCFFFF;"|
|-
| style=""| Imen Brahmi
| style=""|
|-
| style="background-color:#CCFFFF;"| Teodora Sandra Buda
| style="background-color:#CCFFFF;"|
|-
| style=""| Adriana Chis
| style=""|
|-
| style="background-color:#CCFFFF;"| Laurent Clouet
| style="background-color:#CCFFFF;"|
|-
| style=""| Omar Dominguez
| style=""| <email>andres.portillo-dominguez@ucdconnect.ie</email>
|-
| style="background-color:#CCFFFF;"| Yi Han
| style="background-color:#CCFFFF;"|
|-
| style=""| Adriana Hava
| style=""|
|-
| style="background-color:#CCFFFF;"| Jesus Iglesias
| style="background-color:#CCFFFF;"| <email>Jesus.Omana-Iglesias.1@ucdconnect.ie</email>
|-
| style=""| Xi Li
| style=""|
|-
| style="background-color:#CCFFFF;"| Somnath Mazumdar
| style="background-color:#CCFFFF;"|
|-
| style=""| Patrick McDonagh
| style=""| <email>andres.portillo-dominguez@ucdconnect.ie</email>
|-
| style="background-color:#CCFFFF;"| Philip O'Brien
| style="background-color:#CCFFFF;"|
|-
| style=""| Cristi Olariu
| style=""|
|-
| style="background-color:#CCFFFF;"| Sebastian Robitzsch
| style="background-color:#CCFFFF;"| <email>Sebastian.Robitzsch@ucdconnect.ie</email>
|-
| style=""| Thibaud Rohmer
| style=""|
|-
| style="background-color:#CCFFFF;"| Miao Wang
| style="background-color:#CCFFFF;"|
|-
|}

== Invited Visitors ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~ghamri/ Yacine Ghamri-Doudane]
| style=""| CSI/A1.06
| style=""| +353-1-716-xxxx
| style=""| <email>ghamri@ensiie.fr</email>
|-
|}

People:home

2012-03-09T14:04:39Z

Root: /* Post-Graduate Researchers */

__NOTOC__
== Academic Staff ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.csi.ucd.ie/Staff/jmurphy/default.htm John Murphy]
| style=""| CSI/B2.22
| style=""| +353-1-716-2928
| style=""| <email>j.murphy@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| [http://www.csi.ucd.ie/staff/lmurphy/home/ Liam Murphy]
| style="background-color:#CCFFFF;"| CSI/B1.02
| style="background-color:#CCFFFF;"| +353-1-716-2914
| style="background-color:#CCFFFF;"| <email>liam.murphy@ucd.ie</email>
|-
|}

== Research Fellows ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~soufiene.djahel/ Soufiene Djahel]
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>sdjahel@gmail.com</email>
|-
| style="background-color:#CCFFFF;"| [http://performance.ucd.ie/jfitzpatrick/ John Fitzpatrick]
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>johnfitzpat@gmail.com</email>
|-
| style=""| Sean Murphy
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>Sean.Murphy@iname.com</email>
|-
| style="background-color:#CCFFFF;"| Hamid Nafaa
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>nafaa@ieee.org</email>
|-
| style=""| Dawid Nowak
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>dawid.nowak@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| Christina Thorpe
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-xxxx
| style="background-color:#CCFFFF;"| <email>christina.thorpe@gmail.com</email>
|-
| style=""| [http://aventresque.free.fr Anthony Ventresque]
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>anthony.ventresque@ucd.ie</email>
|-
|}

== Post-Graduate Researchers ==

{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| Newres AlHaider
| style=""|
|-
| style="background-color:#CCFFFF;"| Saima Arif
| style="background-color:#CCFFFF;"|
|-
| style=""| Imen Brahmi
| style=""|
|-
| style="background-color:#CCFFFF;"| Teodora Sandra Buda
| style="background-color:#CCFFFF;"|
|-
| style=""| Adriana Chis
| style=""| <email>adriana_e_chis@yahoo.com</email>
|-
| style="background-color:#CCFFFF;"| Laurent Clouet
| style="background-color:#CCFFFF;"|
|-
| style=""| Omar Dominguez
| style=""| <email>andres.portillo-dominguez@ucdconnect.ie</email>
|-
| style="background-color:#CCFFFF;"| Yi Han
| style="background-color:#CCFFFF;"|
|-
| style=""| Adriana Hava
| style=""|
|-
| style="background-color:#CCFFFF;"| Jesus Iglesias
| style="background-color:#CCFFFF;"| <email>Jesus.Omana-Iglesias.1@ucdconnect.ie</email>
|-
| style=""| Xi Li
| style=""| <email>adriana_e_chis@yahoo.com</email>
|-
| style="background-color:#CCFFFF;"| Somnath Mazumdar
| style="background-color:#CCFFFF;"|
|-
| style=""| Patrick McDonagh
| style=""| <email>andres.portillo-dominguez@ucdconnect.ie</email>
|-
| style="background-color:#CCFFFF;"| Philip O'Brien
| style="background-color:#CCFFFF;"|
|-
| style=""| Cristi Olariu
| style=""|
|-
| style="background-color:#CCFFFF;"| Sebastian Robitzsch
| style="background-color:#CCFFFF;"| <email>Sebastian.Robitzsch@ucdconnect.ie</email>
|-
| style=""| Thibaud Rohmer
| style=""|
|-
| style="background-color:#CCFFFF;"| Miao Wang
| style="background-color:#CCFFFF;"|
|-
|}

== Invited Visitors ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~ghamri/ Yacine Ghamri-Doudane]
| style=""| CSI/A1.06
| style=""| +353-1-716-xxxx
| style=""| <email>ghamri@ensiie.fr</email>
|-
|}

People:home

2012-03-09T13:59:33Z

Root: /* Post-Graduate Researchers */

__NOTOC__
== Academic Staff ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.csi.ucd.ie/Staff/jmurphy/default.htm John Murphy]
| style=""| CSI/B2.22
| style=""| +353-1-716-2928
| style=""| <email>j.murphy@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| [http://www.csi.ucd.ie/staff/lmurphy/home/ Liam Murphy]
| style="background-color:#CCFFFF;"| CSI/B1.02
| style="background-color:#CCFFFF;"| +353-1-716-2914
| style="background-color:#CCFFFF;"| <email>liam.murphy@ucd.ie</email>
|-
|}

== Research Fellows ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~soufiene.djahel/ Soufiene Djahel]
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>sdjahel@gmail.com</email>
|-
| style="background-color:#CCFFFF;"| [http://performance.ucd.ie/jfitzpatrick/ John Fitzpatrick]
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>johnfitzpat@gmail.com</email>
|-
| style=""| Sean Murphy
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>Sean.Murphy@iname.com</email>
|-
| style="background-color:#CCFFFF;"| Hamid Nafaa
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>nafaa@ieee.org</email>
|-
| style=""| Dawid Nowak
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>dawid.nowak@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| Christina Thorpe
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-xxxx
| style="background-color:#CCFFFF;"| <email>christina.thorpe@gmail.com</email>
|-
| style=""| [http://aventresque.free.fr Anthony Ventresque]
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>anthony.ventresque@ucd.ie</email>
|-
|}

== Post-Graduate Researchers ==

{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| Newres AlHaider
| style=""| <email>newresa@gmail.com</email>
|-
| style="background-color:#CCFFFF;"| Saima Arif
| style="background-color:#CCFFFF;"|
|-
| style=""| Imen Brahmi
| style=""| <email>hi.brahmi@gmail.com</email>
|-
| style="background-color:#CCFFFF;"| Teodora Sandra Buda
| style="background-color:#CCFFFF;"| <email>dora.sandra10@gmail.com</email>
|-
| style=""| Adriana Chis
| style=""| <email>adriana_e_chis@yahoo.com</email>
|-
| style="background-color:#CCFFFF;"| Laurent Clouet
| style="background-color:#CCFFFF;"| <email>laurent.clouet@gmail.com</email>
|-
| style=""| Omar Dominguez
| style=""| <email>andres.portillo-dominguez@ucdconnect.ie</email>
|-
|}

== Invited Visitors ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~ghamri/ Yacine Ghamri-Doudane]
| style=""| CSI/A1.06
| style=""| +353-1-716-xxxx
| style=""| <email>ghamri@ensiie.fr</email>
|-
|}

People:home

2012-03-09T13:52:29Z

Root:

__NOTOC__
== Academic Staff ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.csi.ucd.ie/Staff/jmurphy/default.htm John Murphy]
| style=""| CSI/B2.22
| style=""| +353-1-716-2928
| style=""| <email>j.murphy@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| [http://www.csi.ucd.ie/staff/lmurphy/home/ Liam Murphy]
| style="background-color:#CCFFFF;"| CSI/B1.02
| style="background-color:#CCFFFF;"| +353-1-716-2914
| style="background-color:#CCFFFF;"| <email>liam.murphy@ucd.ie</email>
|-
|}

== Research Fellows ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~soufiene.djahel/ Soufiene Djahel]
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>sdjahel@gmail.com</email>
|-
| style="background-color:#CCFFFF;"| [http://performance.ucd.ie/jfitzpatrick/ John Fitzpatrick]
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>johnfitzpat@gmail.com</email>
|-
| style=""| Sean Murphy
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>Sean.Murphy@iname.com</email>
|-
| style="background-color:#CCFFFF;"| Hamid Nafaa
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>nafaa@ieee.org</email>
|-
| style=""| Dawid Nowak
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>dawid.nowak@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| Christina Thorpe
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-xxxx
| style="background-color:#CCFFFF;"| <email>christina.thorpe@gmail.com</email>
|-
| style=""| [http://aventresque.free.fr Anthony Ventresque]
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>anthony.ventresque@ucd.ie</email>
|-
|}

== Post-Graduate Researchers ==

{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~soufiene.djahel/ Soufiene Djahel]
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>sdjahel@gmail.com</email>
|-
| style="background-color:#CCFFFF;"| [http://performance.ucd.ie/jfitzpatrick/ John Fitzpatrick]
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>johnfitzpat@gmail.com</email>
|-
| style=""| Sean Murphy
| style=""| CSI/A1.07
| style=""| +353-1-716-2479
| style=""| <email>Sean.Murphy@iname.com</email>
|-
| style="background-color:#CCFFFF;"| Hamid Nafaa
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-2479
| style="background-color:#CCFFFF;"| <email>nafaa@ieee.org</email>
|-
| style=""| Dawid Nowak
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>dawid.nowak@ucd.ie</email>
|-
| style="background-color:#CCFFFF;"| Christina Thorpe
| style="background-color:#CCFFFF;"| CSI/A1.07
| style="background-color:#CCFFFF;"| +353-1-716-xxxx
| style="background-color:#CCFFFF;"| <email>christina.thorpe@gmail.com</email>
|-
| style=""| [http://aventresque.free.fr Anthony Ventresque]
| style=""| CSI/A1.09
| style=""| +353-1-716-2925
| style=""| <email>anthony.ventresque@ucd.ie</email>
|-
|}

== Invited Visitors ==
{| style="color:black; background-color:white;" width="100%" cellspacing="0" border="1"
| style="background-color:#A8A8A8;"| Name
| style="background-color:#A8A8A8;"| Office Room
| style="background-color:#A8A8A8;"| Phone
| style="background-color:#A8A8A8;"| E-mail
|-
| style=""| [http://www.ensiie.fr/~ghamri/ Yacine Ghamri-Doudane]
| style=""| CSI/A1.06
| style=""| +353-1-716-xxxx
| style=""| <email>ghamri@ensiie.fr</email>
|-
|}

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== Startups ==

{|width="100%" align="center" cellpadding="0" cellspacing="50" border="0"
|style="width: 30%;"|[[File:logentries.png|150px|link=https://logentries.com/]]||[https://logentries.com/ Logentries]: "Logs collected in real time, analyzed, stored, and presented in a meaningful way. Anywhere. Anytime." Founded by Dr. Trevor Parsons and Dr. Viliam Holub, former PhD student and post-doc with us.
|}

== Softwares ==

== Patents ==

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2012-03-09T13:49:02Z

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2012-03-09T13:47:32Z

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2012-03-09T13:46:59Z

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Pubs:2006

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<bibtex>
@inproceedings{170,
author={C. Thorpe; S. Murphy; L. Murphy},
title={Seamless Handover in Heterogeneous Radio Access Networks},
booktitle={IT&T},
year={2006},
abstract={This paper provides a detailed discussion of the problem of Seamless Handover in Heterogeneous Radio Access Networks. Brief descriptions of several wireless access technologies are included to provide some background information and to illustrate the importance of solving the seamless handover problem for network subscribers. Several approaches to providing a handover solution have been proposed, some of which will be described and compared, in order to indicate possible directions for continuing to search for a seamless handover solution. Various problems are present in the existing solutions, and are discussed in this paper. These problems are significant enough to warrant further investigation in the handover area, and leave scope for modifications and improvements.},
keywords={Seamless Handover, Heterogenous Networks, SCTP},
pdf={christina-itt06-cameraReady.pdf},
}
</bibtex>
<bibtex>
@inproceedings{161,
author={C. Thorpe; L. Murphy},
title={A Survey of Seamless Handover in Heterogeneous Radio Access Networks},
booktitle={ACM/IEEE International Symposium on Modeling, Analysis and Simulation of Wireless and Mobile Systems},
year={2006},
abstract={This paper provides a detailed discussion of the problem of Seamless Handover in Heterogeneous Radio Access Networks. Several approaches to providing a handover solution have been proposed, some of which will be described and compared, in order to indicate possible directions for continuing to search for a seamless handover solution. Various problems are present in the existing solutions, and are discussed in this paper. },
keywords={Seamless Handover, Heterogenous Networks, SCTP},
pdf={Christina-MSWIM-Oct-2006.pdf},
}
</bibtex>
<bibtex>
@inproceedings{213,
author={J. Fitzpatrick, S. Murphy and J. Murphy},
title={An Approach to Transport Layer Handover of VoIP over WLAN},
booktitle={CCNC},
year={2006},
abstract={In this paper a transport layer handover mechanism for Voice over Internet Protocol (VoIP) using the Stream Control Transmission Protocol (SCTP) is proposed. This handover mechanism utilizes the multi-homing feature of SCTP to allow connection to multiple wireless networks. Each available wireless network is probed with simulated VoIP data to obtain network performance metrics. Handover decisions are made based on the Mean Opinion Score (MOS) calculated from the ITU-T E-Model for voice quality assessment using the obtained measurements. Implementation and simulations were carried out using the NS2 network simulator. The results show the MOS obtained using the proposed handover mechanism on IEEE 802.11b WLAN access points (APs) under varying load conditions. High correlation is shown between the MOS from the proposed handover scheme and the MOS experienced by a VoIP node present in the network. A simulation showing an SCTP endpoint handover between AP’s is presented.},
keywords={SCTP, E-Model, VoIP, Handover, Heterogeneous Networks},
}
</bibtex>
<bibtex>
@inproceedings{214,
author={J. Fitzpatrick, and S. Murphy, and J. Murphy,},
title={SCTP based Handover Mechanism for VoIP over IEEE 802.11b Wireless LAN with Heterogeneous Transmission Rates},
booktitle={Communications, 2006. ICC '06. IEEE International Conference on},
year={2006},
abstract={In this paper a transport layer handover mechanism for Voice over Internet Protocol (VoIP) in 802.11b using the Stream Control Transmission Protocol (SCTP) is proposed. The multi-homing feature of SCTP is used to allow connections to several 802.11b Access Points (AP's). Probing packets that model VoIP encoded data at various transmission rates are used to obtain quality metrics from each of the available networks. Handover decisions are made based on the Mean Opinion Score (MOS) calculated from the ITU-T E-Model for voice quality assessment using the obtained measurements. The handover mechanism is shown to operate in 802.11b networks with heterogeneous transmission rates using multiple VoIP codecs. The results show a high correlation between the MOS predicted by the proposed mechanism and the MOS experienced by a VoIP call present in the network. Results verify the accurate operation of the scheme using multiple VoIP codecs at various transmission rates. A simulation showing an SCTP endpoint handover between heterogeneous transmission rate AP's is presented.},
keywords={SCTP, VoIP},
}
</bibtex>
<bibtex>
@inproceedings{215,
author={J. Fitzpatrick, S. Murphy, J. Murphy},
title={RTS/CTS Based Endpoint Admission Control for VoIP Over 802.11e},
booktitle={MMNS},
year={2006},
abstract={In this paper an endpoint-based admission control mechanism for VoIP over WLAN is proposed. The mechanism operates by first measuring the utilisation of the channel and comparing this to a pre-determined threshold, if the channel utilisation exceeds this threshold, the call is rejected. One important aspect of the mechanism is that it can operate in the presence of hidden terminals. This is done by using the Request-to-Send/Clear-to-Send WLAN signalling to determine channel utilisation. The scheme is designed to be flexible; it can operate with heterogeneous data rates, with varying traffic types and in the presence of legacy 802.11 nodes. The scheme was developed and evaluated using the Qualnet network simulator. An empirical approach was used to determine appropriate admission thresholds. Then, simulations were performed to demonstrate the successful operation of the scheme.},
keywords={Call Admission Control, VoIP, 802.11e, RTS/CTS},
}
</bibtex>
<bibtex>
@inproceedings{311,
author={Carrig,B.;Denieffe,D.;Murphy,J.},
title={A Relative Delay Minimization Scheme for Multiplayer Gaming in Diffrentiated Services Network},
booktitle={ACM SIGCOMM Workshop on Network & System Support for Games},
year={2006},
abstract={Multiplayer gaming over the Internet continues to grow in popularity, despite a lack of Quality of Service (QoS) mechanisms. Future QoS-aware networks such as those based on the Differentiated Services (DiffServ) framework will provide an opportunity for gamers to enhance their game-playing experience. An important QoS metric for networked games is a user’s delay relative to the delay of other users. In this paper, we propose a Relative Delay Minimization (RDM) algorithm for use in DiffServ environments. Simulation results are described and presented showing that the algorithm can reduce the Relative Delay Variation (RDV) between users in a DiffServ environment.},
keywords={Network Games, Relative Delay, DiffServ, QoS},
pdf={a relative delay.pdf},
}
</bibtex>
<bibtex>
@inproceedings{312,
author={Noonan,J.;Perry,P.;Murphy,J.},
title={End-point Synchronisation & Handover For Multi-homed Services},
booktitle={IEE Proceedings-Communications},
year={2006},
abstract={It is proposed to implement a synchronised routing table at the transport layer, referred to as an Association Routing Table (ART), to improve the performance of multi-homed transport protocols. An algorithm is described that ensures that the routing tables can be synchronised, which is then used to implement a handover mechanism. The ART is implemented within SCTP. It is shown that by using a synchronised ART, it is possible to implement failover in cases where standard SCTP cannot, con¯gurations are more resilient to network errors, and it is possible to perform a handover without any network support.},
keywords={Multi-homing, routing, transport layer, SCTP, handovers},
pdf={end point-sychronization.pdf},
}
</bibtex>
<bibtex>
@inproceedings{313,
author={Hillestad,O.I.;Perkis,A.;Genc,V.;Murphy,S.;Murphy,J.},
title={Delivery of On-Demand Video Services in Rural Areas via IEEE 802.16 Broadband Wireless Access Networks},
booktitle={ACM 2nd Workshop on Wireless Multimedia Networking & Performance Modelling },
year={2006},
abstract={A simulation study of delivery of streaming video on-demand via IEEE 802.16 based technologies is described. A number of scenarios are simulated which are representative of rural area deployments of such technologies. The study finds that IEEE 802.16 can support up to 9/10 simultaneous users streaming typical cinematic video content in CIF resolution, 24 frames/s, at average rates of around 750 kbps. Further, the study demonstrates the utility of H.264/AVC Scalable Video Coding (SVC) and a buffer-based congestion control algorithm in an adaptive video streaming solution.},
keywords={IEEE 802.16, video streaming, scalable video coding},
pdf={delivering of on demand.pdf},
}
</bibtex>
<bibtex>
@inproceedings{314,
author={Ormond,O.;Muntean,G.;Murphy,J.},
title={Evaluation of an Intelligent Utility-Based Strategy for Dynamic Wireless Network Selection},
booktitle={Autonomic Management of Mobile Multimedia Services},
year={2006},
abstract={In the case of next generation wireless networks, different users with various multi-homed personal wireless devices will aim to exploit the full potential of the choice of services and applications available over different radio access networks. In their selection of a certain radio access network consumers will consider money and delay preferences for the current application and will rely on intelligent network-selection decision strategies to aid them in their choice. This paper describes the evaluation of an intelligent utility-based strategy for network selection in a multi-access network situation for transfer of large non real-time data files. A number of scenarios are examined which compare the proposed network selection strategy against other possible strategies. Test results show how by using this network selection strategy significant benefits in terms of combined average delay and cost per file transferred as well as transfer efficiency are obtained.},
keywords={Heterogeneous Wireless Networks, Multi-homed Radio Terminals, User-centric Network Selection.},
pdf={evaluation.pdf},
}
</bibtex>
<bibtex>
@inproceedings{315,
author={Parsons,T.;Mos,A.;Murphy,J.},
title={Non-Intrusive End to End Run-time Path Tracing for J2EE Systems},
booktitle={IEE Proceedings-Software},
year={2006},
abstract={An end-to-end runtime path-tracing approach for J2EE systems has been introduced. The approach is non-intrusive and thus does not require instrumentation of middleware or application source code. The implementation of the system has been realised in the COMPAS Java end-to-end monitoring tool that extends and integrates a number of open source projects. The first set of results shows the performance overhead associated with the tool. Further results show the portability of this approach, by applying it to a number of different application server implementations. Finally, it is also shown that runtime paths collected by the implementation can be used for reasoning about the overall system structure and design of complex enterprise applications.},
keywords={IEEE ,Server},
pdf={non-intrusive.pdf},
}
</bibtex>
<bibtex>
@inproceedings{316,
author={Barrett,R.;Pahl,C.;Patcas,L.M.;Murphy,J.},
title={Model Driven Distribution Pattern Design for Dynamic Web Service Compositions},
booktitle={ACM 6th International Conference on Web Engineering,ICWE},
year={2006},
abstract={Web service compositions are often used to realise servicebased enterprise applications. These enterprise systems are built from many existing discrete applications, often legacy applications exposed using Web service interfaces. Acceptance of these systems is often constrained by non-functional aspects, such as Quality of Service (QoS). A number of factors a�ect the QoS of an enterprise system, including availability, scalability and performance. There are a number of architectural con�gurations or distribution patterns, which express how a composed system is to be deployed. These distribution patterns have a direct impact upon the QoS of the composition. However, the amount of code required to realise these distribution patterns is considerable. Additionally, there is an increased deployment time associated with setting up di�erent distribution patterns. We therefore propose a novel approach which combines a Model Driven Architecture using UML 2.0 for modeling and subsequently generating Web service compositions, with a method for achieving dynamic decentralised interaction amongst services with reduced deployment overheads. These approaches combined provide for the generation of dynamic Web service compositions driven by a distribution pattern model.},
keywords={Distribution patterns, Web services, compositions, decentralisation, MDA},
pdf={model driven.pdf},
}
</bibtex>
<bibtex>
@inproceedings{317,
author={Ormond,O.;Murphy,J.;Muntean,G.},
title={Utility-based Intelligent Network Selection in Beyond 3G Systems},
booktitle={IEEE International Conference on Communications},
year={2006},
abstract={Development in wireless access technologies and multihomed personal user devices is driving the way towards a heterogeneous wireless access network environment. Success in this arena will be reliant on the ability to offer an enhanced user experience. Users will plan to take advantage of the competition and always connect to the network which can best service their preferences for the current application. They will rely on intelligent network selection decision strategies to aid them in their choice. The contribution of this paper is to propose an intelligent utility-based strategy for network selection in this multi-access network scenario. A number of utility functions are examined which explore different user attitudes to risk for money and delay preferences related to their current application. For example we show that risk takers who are willing to pay more money get a better service.},
keywords={Wireless Networks,3G},
pdf={utility.pdf},
}
</bibtex>
<bibtex>
@inproceedings{318,
author={Carrig,B.;Denieffe,D.;Murphy,J.},
title={Delivering Quality of Service for Gaming Applications in Best Effort Networks},
booktitle={13th International Conference on Telecommunications},
year={2006},
abstract={This paper describes a scheduler which provides non-elevated Quality of Service (QoS) for two different classes of traffic. A Delay-Sensitive (DS) class receives a low delay service at the expense of an increased probability of packet loss. The non-DS traffic receives at least the same level of throughput as it would in an ordinary best effort network. The design of the scheduler is presented and contrasted with similar schedulers such as the Alternative Best Effort (ABE) service. Simulation results for a network carrying a mixture of FTP and Quake 3 multiplayer gaming traffic are also shown. It was discovered that even for a heavily-loaded network, with a large proportion of non-DS traffic, there are benefits for interactive games traffic availing of the DS service.},
keywords={Networked Games, Non-elevated QoS, Quality of Service},
pdf={delivering quality.pdf},
}
</bibtex>
<bibtex>
@inproceedings{319,
author={Noonan,J.;Perry,P.;Murphy,S.;Murphy,J.},
title={Stall & Path Monitoring Issues in SCTP,IEEE Infocom},
booktitle={Conference on Computer Communications},
year={2006},
abstract={This paper presents how SCTP can stall in multihomed scenarios during failover and under certain circumstances. A stall is where an SCTP end-point ceases to communicate for an extended period of time, but does not report any error to the upper layer. This paper presents two different sets of circumstances where a stall can occur: firstly when there is an underestimation of the Retransmission Time-Out (RTO) value for a redundant network path; and secondly when a network error occurs that causes only SACKs to be lost, which confuses the SCTP sender about which network path is operational. Solutions to both of these stalls are presented that include modifying the RTO value, applying Karn’s algorithm to path monitoring and ensuring the destination address selection policy for SACKs is changed. This paper also presents a mechanism to de-couple data acknowledgement and path monitoring when using multi-homed transport protocols, which should remove the ambiguity about path monitoring and offers a universal solution to the stall.},
keywords={SCTP},
pdf={stall and path.pdf},
}
</bibtex>
<bibtex>
@inproceedings{320,
author={Ormond,O.;Murphy,J.;Muntean,G.},
title={Economic Model for Cost Effective Network Selection Strategy in Service Oriented Heterogenous Wireless Network Environment},
booktitle={10th IEEE/IFIP Network Operations & Management Symposium},
year={2006},
abstract={This paper describes and formalises the Service Oriented Heterogeneous Wireless Network Environment (SOHWNE)A the future service provision and delivery environment that will support ubiCuitous user access anywhere at any time from diverse devices to a broad range of services. These services can be offered by third parties and can be accessed via one of many available networks. This paper also proposes and describes a novel algorithm for intelligent costoriented and performance-aware selection between available networks. This user-centric strategy focuses on the maximisation of consumer surplus when selecting the best available connection for transferring non real-time dataA with user specified time constraintsA in a user-centric SOHWNE.},
keywords={Consumer SurplusA Decision-making StrategiesA Multi-provider Network EnvironmentA Non real-time Data.},
pdf={economic model.pdf},
}
</bibtex>
<bibtex>
@inproceedings{321,
author={Parsons,T.;Murphy,J.},
title={The 2nd International Middleware Doctoral Symposium:Detecting Performance Antipatterns in Component-Based Enterprise Systems},
booktitle={IEEE Distributed Systems Online },
year={2006},
abstract={Internet-enabled enterprise applications often fail to meet their performance requirements. This can lead to development delays or, even worse, loss of business due to customer dissatisfaction with sluggish or unreliable service. Inefficient enterprise systems are often the result of system developers making incorrect or suboptimal design decisions. Such decisions occur because today’s enterprise applications are extremely large and complex, and developers often don’t completely understand the entire application. Consequently, they often don’t completely understand the performance implications of their design decisions, and as a result, systems frequently fail to meet their performance agreements. },
keywords={Performance Oriented,},
pdf={2nd international.pdf},
}
</bibtex>
<bibtex>
@inproceedings{391,
author={A.Ufimtsev;L.Murphy},
title={Performance Modelling of a JAVAEE Component Application using Layered Queuing Networks:Revised Approach & a Case Study},
booktitle={Specification & Verification of Component-Based Systems(SAVCBS'06)},
year={2006},
abstract={Nowadays component technologies are an integral part of any enterprise production environment. Performance and scalability are among the key properties of such systems. Using Layered Queuing Networks (LQN), one can predict the performance of a component system from its design. This work revises the approach of using LQN templates and offers a case study by using the revised approach to model a realistic component application. Both strong points and shortcomings of the approach are discussed.},
keywords={performance modeling, JavaEE, component systems, ECPerf, Layered Queuing Network.},
pdf={performance.pdf},
}
</bibtex>
<bibtex>
@inproceedings{392,
author={A.Ufimtsev;T.Parsons;L.Patcas;J.Murphy;L.Murphy},
title={Introducing Performance Engineering by means of Tools & Practical Exercises},
booktitle={Annual International Conference on Computer Science & Software Engineering},
year={2006},
abstract={Many software engineers complete their education without an introduction to the most basic performance engineering concepts. IT specialists need to be educated with a basic degree of performance engineering knowledge, so they are aware of why and how certain design and development decisions can lead to poor performance of the resulting software systems. To help address this need, the School of Computer Science and Informatics at University College Dublin offered a final year undergraduate/first year postgraduate module on ”Performance of Computer Systems” in Autumn 2005. In this paper we document how performance engineering was introduced to the students through practical exercises, and how these exercises relate to industry problems.},
keywords={Software,J2EE},
pdf={introducing performance.pdf},
}
</bibtex>
<bibtex>
@inproceedings{393,
author={A.Ufimtsev;L.Murphy},
title={Automatic System for Linux Kernel Performance Testing},
booktitle={2006 Linux Symposium},
year={2006},
abstract={We introduce an automatic and open kernel testing system. We argue that only by opening a test system to the community and aggregating the results from a variety of sources can one get a comprehensive picture of the kernel’s performance status. Our system can also help identifying problems with specific parts of code whether it is a device driver, some other module, or platform-specific code. Design of both client and server parts of the system is described. Since system is open, specific emphasis in client part is placed on successful automation and configuration of the testing process. The emphasis of the server part is placed on regression detection and accidental/malicious input elimination. Current implementation status is presented.},
keywords={Kernel System,Linux},
pdf={automatic.pdf},
}
</bibtex>
<bibtex>
@inproceedings{394,
author={A.Ufimtsev;A.Kucherenko;L.Murphy},
title={Impact of Virtual Managers on Performance of J2EE Applications},
booktitle={9th International Symposium on Component-Based Software Engineering},
year={2006},
abstract={We investigate the impact of Operating System's Virtual Memory Managers (VMMs) on performance of enterprise applications. By taking various popular branches of the Linux kernel and modifying their VMM settings, one can see the e®ects it introduces on ECPerf J2EE Benchmark. JBoss application server is used to run ECPerf. Our tests show that even the change of one parameter in VMM can have signi¯cant performance impacts. Performance of various kernel branches is compared. Parameter sensitivity and in°uence of speci¯c settings are presented.},
keywords={Operating System,J2EE,Linux},
pdf={impact.pdf},
}
</bibtex>
<bibtex>
@inproceedings{395,
author={P.McGovern;S.Murphy;L.Murphy},
title={Protection Againest Link Adaptation for VoWLAN},
booktitle={15th IST Mobile & Wireless Communications Summit},
year={2006},
abstract={In this paper a scheme is proposed to deal with the problem of Link Adaptation (LA) of an ongoing call in a Voice over Wireless Local Area Network (VoWLAN) environment. The scheme operates by dropping the call from the system if the LA affects the call quality of the other ongoing calls. The proposed scheme was evaluated on an experimental test-bed and results show that it protected the quality levels of the other ongoing calls under various network configurations.},
keywords={Voice over IP (VoIP), IEEE 802.11, Admission Control (AC), Link Adaptation (LA)},
pdf={protection.pdf},
}
</bibtex>
<bibtex>
@article{396,
author={N.Cranley;L.Murphy},
title={Incorporating User Perception in Adaptive Video Streaming Systems},
journal={Digital Multimedia Perception & Design},
year={2006},
pages={860-861},
volume={May 2006},
abstract={There is an increasing demand for streaming video applications over both the fixed
Internet and wireless IP networks. The fluctuating bandwidth and time-varying delays
of best-effort networks makes providing good quality streaming a challenge. Many
adaptive video delivery mechanisms have been proposed over recent years; however,
most do not explicitly consider user-perceived quality when making adaptations, nor
do they define what quality is. This chapter describes research that proposes that an
optimal adaptation trajectory through the set of possible encodings exists, and
indicates how to adapt transmission in response to changes in network conditions in
order to maximize user-perceived quality.},
keywords={Video Streaming,Internet,IP Networks},
pdf={incorporating.pdf},
}
</bibtex>
<bibtex>
@inproceedings{397,
author={P.McGovern;S.Chung;S.Murphy;L.Murphy},
title={Endpoint Admission Control for VoIPoWLAN },
booktitle={13th International Conference of Telecommunications},
year={2006},
abstract={In this paper a Call Admission Control (CAC) scheme for Voice over Internet Protocol (VoIP) over a Wireless Local Area Network (WLAN) is proposed. The CAC scheme is based on the Endpoint Admission Control (EAC) paradigm where the endpoints, i.e. the WLAN terminals, probe the network to ascertain if the call can be supported with acceptable Quality of Service (QoS). The proposed scheme was evaluated on an experimental test-bed and test results show that correct Admission Control (AC) decisions were made under various network configurations.},
keywords={Voice over IP (VoIP), Wireless Local Area Network (WLAN), IEEE 802.11, Admission Control (AC)},
pdf={end point.pdf},
}
</bibtex>
<bibtex>
@article{410,
author={C.H.Muntean;J.McManis},
title={End-User Quality of Experience Oriented Adaptive E-learning System},
journal={Journal of Digital Information},
year={2006},
pages={1},
volume={7},
abstract={In the context of new devices and with a variety of network technologies that allow access to the Internet, the providers of e-learning materials have to ensure that the users have a positive experience using their e-learning systems and they are happy to re-use them. Adaptive Hypermedia research aims to provide personalised educational material that ensures a positive learning experience for the end-users. However, user experience is dependent not only on the content served to them, but also on the user perceived performance of the e-learning system. This leads to a new dimension of individual differences between Web users: the end-user Quality of Experience (QoE). We have proposed a solution for Adaptive Hypermedia Systems (AHS) that provides satisfactory end-user QoE through the use of a new QoE layer. This layer attempts to take into account multiple factors affecting QoE in relation to the delivery of a wide range of Web components such as text, images, video, audio.

The effectiveness of our QoE layer has been tested in comparison to a standard educational AHS and the results of these tests are presented in this paper. Different educational-based evaluation techniques such as learner achievement analysis, learning performance assessment, usability survey and correlation analysis between individual student performance and judgment on system usability were applied in order to fully assess the performance of the proposed QoE layer. Results of the tests showed that the use of the QoE layer brought significant improvements in terms of user learning performance, system usability and user satisfaction with the personalised e-learning system while not affecting the user learning achievement
},
keywords={end-user QoE, adaptive hypermedia, e-learning, end-user perceived performance, learning performance },
pdf={end user quality.doc},
}
</bibtex>
<bibtex>
@inproceedings{418,
author={P.McGovern;S.Murphy;L.Murphy},
title={Addressing the Link Adaptation Problem for VoWLAN using Codec Adaptation},
booktitle={IEEE Globecom 2006-Wireless Communications & Networking},
year={2006},
abstract={In this paper a scheme is proposed to deal with congestion problems that can arise due to Link Adaptation (LA) in Wireless Local Area Networks (WLANs) in the presence of VoIP traffic. The proposed scheme operates by first determining if LA has resulted in the system becoming congested. If not, no further action is taken. However, if, LA has resulted in an overloaded system, the voice codec of the handset which has undergone LA is adapted so as to restore the system to its earlier state, thereby alleviating the congestion. This is achieved by specifically adapting the codec so as to maintain approximately the same level of medium usage as was used prior to the LA. The proposed scheme was evaluated on an experimental test-bed and results show that the codec adaptation was very effective at overcoming the problem of LA.},
keywords={Voice over IP (VoIP), IEEE 802.11, Admission},
pdf={addressing.pdf},
}
</bibtex>
<bibtex>
@article{419,
author={N.Cranley;P.Perry;L.Murphy},
title={User Perception of Adapting Video Quality},
journal={International Journal of Human-Computer Studies/Knowledge Acquisition},
year={2006},
pages={637-647},
volume={64},
abstract={In general, video quality adaptation and video quality evaluation are distinct activities. Most adaptive delivery mechanisms for
streaming multimedia content do not explicitly consider user-perceived quality when making adaptation decisions. Equally, video quality
evaluation techniques are not designed to evaluate instantaneous quality where the quality is changing over time. We propose that an
Optimal Adaptation Trajectory (OAT) through the set of possible encoding exists, and that it indicates how to adapt encoding quality in
response to changes in network conditions in order to maximize user-perceived quality. The subjective and objective tests carried out to
find such trajectories for a number of different MPEG-4 video clips are described. Experimental subjective testing results are presented
that demonstrate the dynamic nature of user perception with adapting multimedia. The results demonstrate that adaptation using the
OAT out-performs conventional adaptation strategies in which only a single aspect of the video quality is adapted. In contrast, the OAT
provides a mechanism to adapt multiple aspects of the video quality thereby giving better user-perceived quality in both the short and
long term.},
keywords={Video quality; Evaluation/methodology; Perception; Subjective and objective quality; Adaptation},
pdf={user perception.pdf},
}
</bibtex>
<bibtex>
@article{420,
author={N.Cranley;L.Murphy;P.Perry},
title={Dynamic Content-Based Adaptation of Streamed Multimedia,Intelligence-based Adaptation for Ubiquitous Multimedia Communications},
journal={Journal of Network & Computer Applications},
year={2006},
pages={983-1006},
volume={30},
abstract={Most adaptive delivery mechanisms for streaming multimedia content do not explicitly
consider user-perceived quality when making adaptation decisions. We show that an optimal
adaptation trajectory (OAT) through the set of possible encodings exists, and that it indicates
how to adapt encoding quality in response to changes in network conditions in order to
maximise user-perceived quality. The OAT is related to the characteristics of the content, in
terms of spatial and temporal complexity. We describe a method to automatically determine
the OAT in response to the time-varying characteristics of the content. In this way, as the
characteristics of the content change over time, the system can dynamically and intelligently
adjust the adaptation process in order to maximise the user-perceived quality. The OAT can
be used with any sender-based transmission adaptation policy. We demonstrate content-based
adaptation using the OAT in a practical system using two different adaptation algorithms.
Furthermore, we show how this form of adaptation can result in differing adaptation
behaviour not only as a result of the dynamics of the content but also as a result of the
adaptation algorithm being used. Finally, we show how increased feedback frequency does not
necessarily improve the behaviour of the adaptation algorithm being used.},
keywords={User perception; Video quality; Adaptive systems; Multimedia},
pdf={dynamic.pdf},
}
</bibtex>
<bibtex>
@inproceedings{426,
author={Muntean,C.H.;McManis,J},
title={The Value of QoE-based adaptation approach in educational hypermedia:Empirical evaluation},
booktitle={4th International Conference on Adaptive Hypermedia & Adaptive Web-Based Systems},
year={2006},
abstract={This paper reports the results of a comparison-based empirical study on the applicability of the end-user Quality of Experience-based content adaptation mechanism in adaptive educational hypermedia. The focus of the paper will be the experiment itself: the initial settings, testing scenarios and the results. We will show that for low bit rate connections the QoE-based adaptation decreases study session time, information processing time per page and the number of re-visits to a page, it maintains similar learning outcomes while also improving the user quality of experience and satisfaction with the system. Finally we will comment on the results and interpret them.},
keywords={QoE},
pdf={value of qoe.pdf},
}
</bibtex>
<bibtex>
@inproceedings{427,
author={Muntean,C.H;Muntean,G.M;Cristea},
title={Authoring Model for Quality of Experience-aware adaptive hypermedia systems},
booktitle={4th International Conference on Adaptive Hypermedia & Adaptive Web-Based Systems},
year={2006},
abstract={This paper presents a novel authoring framework for Quality of Ex-perience (QoE) aware Adaptive Hypermedia Systems. It extends the LAOS au-thoring model in order to consider delivery performance issues. The paper formalises and exemplifies the newly proposed QoE extensions for the LAOS Adaptation and Presentation Models that include QoE Characteristics and QoE Rules layers.},
keywords={QoE,LAOS},
pdf={authoring.pdf},
}
</bibtex>
<bibtex>
@inproceedings{428,
author={Rovcanin,L.;Muntean,C.H.;Muntean,G.M.},
title={Performance Enhancement for Open Corpus Adaptive Hypermedia Systems},
booktitle={4th International Conference on Adaptive Hypermedia & Adaptive Web-Based Systems},
year={2006},
abstract={Adaptive Hypermedia Systems adjust the content to best suit users’ personal characteristics, but rarely consider delivery performance. Performance issues are even more significant in distributed architectures such as that of an Open Corpus Adaptive Educational Hypermedia System (OAEHS). This paper introduces a Performance Oriented Adaptation Agent (POAA) that enhances OAEHS by taking into consideration not only user personal characteristics but also network delivery conditions in the content selection process. The usage of POAA is expected to bring significant delivery performance improvements in terms of learner satisfaction and learning outcome.},
keywords={OAEHS,POAA,Hypermedia},
pdf={performance enhancement.pdf},
}
</bibtex>
<bibtex>
@inproceedings{429,
author={Muntean,C.H.;McManis,J.},
title={Fine Grained Content-Based Adaptation Mechanism for Providing High End-User Quality of Experience with Adaptive Hypermedia Systems },
booktitle={15th W3C International World Wide Web Conference},
year={2006},
abstract={New communication technologies can enable Web users to access personalised information “anytime, anywhere”. However, the network environments allowing this “anytime, anywhere” access may have widely varying performance characteristics such as bandwidth, level of congestion, mobility support, and cost of transmission. It is unrealistic to expect that the quality of delivery of the same content can be maintained in this variable environment, but rather an effort must be made to fit the content served to the current delivery conditions, thus ensuring high Quality of Experience (QoE) to the users. This paper introduces an end-user QoE-aware adaptive hypermedia framework that extends the adaptation functionality of adaptive hypermedia systems with a fine-grained content-based adaptation mechanism. The proposed mechanism attempts to take into account multiple factors affecting QoE in relation to the delivery of Web content. Various simulation tests investigate the performance improvements provided by this mechanism, in a home-like, low bit rate operational environment, in terms of access time per page, aggregate access time per browsing session and quantity of transmitted information.},
keywords={QoE,WebUsers,Bandwidth},
pdf={fine grained.pdf},
}
</bibtex>
<bibtex>
@inproceedings{430,
author={Muntean,C.H.;Muntean,G.M.},
title={Framework for Interactive Personalised IPTV for Entertainment},
booktitle={15th W3C International World Wide Web Conference},
year={2006},
abstract={Interactive IPTV is seen as the future for delivering TV services as it brings all the benefits of computer-based IP networking to the residential viewers. This paper presents the iPersonal IPTV framework that enhances the existing interactive IPTV solution with viewer-oriented personalisation and network and device-based adaptation. This framework is proposed in order to provide significant benefits in terms of viewers' Quality of Experience and to increase their satisfaction. The iPersonal IPTV framework is exemplified in the area of entertainment distribution to remote residential users.},
keywords={Personalisation, network and device adaptation, IPTV, Quality of Experience, user modeling.},
pdf={framework.pdf},
}
</bibtex>
<bibtex>
@inproceedings{431,
author={Muntean,C.H.;Muntean,G.M.},
title={Cost-Oriented Selection & Delivery of E-Content over Various Wireless Networks},
booktitle={IEEE International Conference on Wireless Broadband & Ultra Wideband Communications},
year={2006},
abstract={As wireless technologies are competing with wired solutions in delivering information, there is a clear shift of e-learning towards mobile learning (m-learning). M-learning, which involves both wireless communications and mobile computing, provides learning opportunities to people without wire-based Internet infrastructure or that are continually on the move. At the same time, a large number of educational e-content providers produce and distribute materials that cover a wide range of topics (very often different providers may cover the same topic), differ in quality or presentation format and have different cost. In this context this paper presents a COST-efficient PERsonalised Wireless based E-LEARNing Service (Cost/We-Learn) that provides support for the selection and distribution of personalised educational rich media content (e.g. multimedia, pictures, graphics and text) that best suits user goals, device and cost constraints. Assuming that the user has simultaneous access to multiple wireless networks, Cost/We-Learn enables the selection of that access network over which the selected personalised content will be delivered such as the overall cost matches user budget constraints. This overall cost includes both the price paid for the selected educational material and the delivery cost.},
keywords={Wireless Communication,E-Learning,Cost-Oriented},
pdf={cost oriented.pdf},
}
</bibtex>
<bibtex>
@inproceedings{439,
author={E.Casey;Gabriel-Miro Muntean},
title={A Priority Based Adaptive Scheme for Wireless Multimedia Delivery},
booktitle={IEEE International Conference on Multimedia & Expo(ICME)},
year={2006},
abstract={In wireless multimedia streaming, there is a need to allow for client prioritisation in order to enable provision of end user perceived quality in direct relationship with client device importance. Currently, the same priority is given to all clients, independent of their characteristics, often resulting in unfair distribution of throughput. This paper proposes a priority-based wireless adaptive multimedia delivery scheme that enables client prioritisation during multimedia distribution over IP networks. The paper presents simulation results outlining the benefits of applying the algorithm, illustrating the improvement in bandwidth allocation and in overall end user perceived quality. The algorithm focuses on a residential wireless local area network and assigns static priorities based on device characteristics.},
keywords={Wireless Communication,Multimedia Streaming},
pdf={priority.pdf},
}
</bibtex>
<bibtex>
@inproceedings{451,
author={Gabriel-Miro Muntean},
title={Efficient Delivery of Multimedia Streams over Broadband Networks using QOAS},
booktitle={IEEE Trans. on Broadcasting},
year={2006},
abstract={Quality Oriented Adaptation Scheme (QOAS) is compared against other adaptive schemes such as TCP Friendly Rate Control Protocol (TFRCP), Loss-Delay-based Adaptation Algorithm (LDA+), and a nonadaptive (NoAd) solution when streaming multiple multimedia clips with various characteristics over broadband networks. Streaming efficiency is assessed in terms of loss rate, bandwidth utilization, number of concurrent clients and end-user perceived quality. Simulation results show that using QOAS a significantly higher number of simultaneous clients can be served than when using the other schemes given a target average end-user quality. This is while having higher bandwidth utilization. Testing results also indicate that higher performance is achieved when streaming to the same number of clients using QOAS than when other solutions are used.},
keywords={Adaptive streaming, congestion control, end-user},
pdf={efficient.pdf},
}
</bibtex>

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<bibtex>
@inproceedings{267,
author={Mos,A. ; Murphy,J.},
title={Performance Monitoring of JAVA Component-Oriented Distributed Applications},
booktitle={IEEE 9th International Conference on Software,Telecommunication & Computer Networks},
year={2001},
abstract={We present a framework for monitoring the performance of component oriented distributed applications based on the Enterprise Java Beans specification. The environment leverages EJB architecture to monitor existing applications in real-time and to provide detailed run-time information that help identify performance hotspots at an object-oriented level. It is non-intrusive, portable across all EJB compliant application servers and easily extendable to accommodate new data-acquisition or graphical presentation components. Current status of the work serves as proof of concept and a complete implementation is under development.},
keywords={performance, monitoring, EJB, component-oriented, distributed systems},
pdf={performance monitoring.pdf},
}
</bibtex>
<bibtex>
@inproceedings{268,
author={Hava-Muntean,C.;McManis,J.;Murphy,J.},
title={The Influence of Web Page Images on the Performance of Web Servers},
booktitle={International Confrence on Networking},
year={2001},
abstract={In recent years World Wide Web traffic has shown phenomenal growth. The main causes are the continuing increase in the number of people navigating the Internet and the creation of millions of new Web sites. In addition, the structure of Web pages has become more complex, including not only HTML files but also other components. This has affected both the download times of Web pages and the network bandwidth required. The goal of our research is to monitor the download times of Web pages from different Web sites, and to find out to what extent the images contained in these Web pages influence these times. We also suggest some possible ways of decreasing the bandwidth requirements and download times of complex Web pages.},
keywords={Web Servers},
pdf={influence of web page.pdf},
}
</bibtex>
<bibtex>
@inproceedings{269,
author={Mos,A.;Murphy,J.},
title={New Methods for Performance Monitoring of J2EE Applications Servers},
booktitle={IEEE 8th International Conference on Telecommunications},
year={2001},
abstract={There is a growing need for high performance enterprise distributed systems that provide the scalability and availability required by modern enterprise portals and ecommerce systems. New technologies such as Enterprise Java Beans help building these systems by providing the framework to support the increasingly complex applications. Their performance, however, is not guaranteed by the technology itself and it is mostly the responsibility of the developers to build the application so that it meets the required performance needs. We present a number of approaches for monitoring existing Enterprise Java Beans applications in order to help the developers identify performance problems at an object-oriented level.},
keywords={Applications Servers},
pdf={new methods.pdf},
}
</bibtex>
<bibtex>
@inproceedings{270,
author={Hava-Muntean,C.;McManis,J.; Murphy,J.},
title={A New Dynamic Web Server},
booktitle={8th International Conference on Telecommunication},
year={2001},
abstract={The growth of traffic on the Internet and the explosion in the number of Web sites created in recent years make Web server performance an important issue for Web site designers. To improve the server's performance, it is necessary to determine the main factors affecting it before proposing new solutions for Web server design. Here we first present some experimental results on factors which influence Web server performance. We show how the number of concurrent clients accessing the server and the overall network traffic dynamics affect the performance. The details of a Web page’s composition are also studied to determine their effect on performance. Then we describe a new approach for developing a Web server, in which the server takes its performance as the clients see it into account and dynamically generates the requested Web pages. Their content depends on the traffic conditions and client capabilities. Some results are described to show the feasibility of our proposed design.},
keywords={Web Servers},
pdf={new dynamic.pdf},
}
</bibtex>
<bibtex>
@inproceedings{271,
author={Nowicki,E.;Murphy,J.},
title={Resource Allocation for Interactive traffic classes over GPRS Network},
booktitle={IEE 17th UK Teletraffic Symposium},
year={2001},
abstract={The General Packet Radio Service (GPRS) is a new bearer service for GSM that greatly simplify wireless access to packet data networks, e.g., to the Internet, to the corporate LAN or to the mobile portals. It applies a packet radio standard to transfer user data packets in a well-organized way between Mobile Stations (MS) and external packet data networks. The introduction of guaranteed performance services in GPRS networks requires detailed studies of the resource allocation and service integration issue. This paper proposes some different schemes of allocating the physical channels to mobile stations. We consider the integration of voice and data over Time Division Multiple Access wireless cellular networks. We describe different radio resource allocation algorithms, and describe their similarities and differences in the context of GSM and GPRS networks. However these algorithms can be used for diversified types of wireless networks. In this paper we consider the interactive best effort traffic class as one of the most important traffic classes in GPRS.},
keywords={GPRS },
pdf={rsource allocation.pdf},
}
</bibtex>
<bibtex>
@inproceedings{272,
author={Hava-Muntean,C.;McManis,J.; Murphy,J.;Murphy,L.},
title={A Client-Oriented Dynamic Web Server},
booktitle={IEE 17th UK Teletraffic Symposium},
year={2001},
abstract={The cost of computer systems has decreased continuously in recent years, leading to an exponential growth in the number of computer users. In such an environment, more and more Web servers have been created offering many types of information. As a result Internet traffic has grown significantly, affecting the quality of the services offered by the Web servers. We propose a new approach for designing Web servers, which takes into account client requirements and constraints, and whose implementation is based on Java servlet and applet technology. This client-orientated Web server classifies each client into one of a number of pre-defined categories. The Web page generated for a client then depends on the client's current category. A Web page generated in this way may differ from one generated for another client in its content, number of images, graphic design and structure.},
keywords={Web Servers},
pdf={Client Oriented.pdf},
}
</bibtex>
<bibtex>
@inproceedings{350,
author={M.Narbutt;L.Murphy},
title={Adaptive Playout Buffering for H.323 Voice over IP applications},
booktitle={Irish Signals & Systems Conference 2001},
year={2001},
abstract={In this paper we investigate the performance of various buffer algorithms that might be implemented in H.323 VoIP applications. The main objective of those algorithms is to minimize effect of the delay jitter. We have tested those algorithms in the Internet using H.323 VoIP terminals. Our results show that the algorithm proposed by us can achieve the lowest rate of lost packets while adding acceptably small delays.},
keywords={VoIP,Internet},
pdf={adaptive playout.pdf},
}
</bibtex>
<bibtex>
@inproceedings{351,
author={N.Cranley;L.Murphy},
title={Adaptive Quality of Service for Streamed MPEG-4 over the Internet},
booktitle={International Conference on Communications},
year={2001},
abstract={Currently multimedia is either downloaded before viewing, or streamed over a network. However, streaming real-time or near real-time applications with a specified Quality of Service (QoS) over the Internet is not yet a solved problem. The Real-time Transport Protocol (RTP) can be used to facilitate streaming, but also has the potential to support QoS. By gathering network statistics during the session and defining different QoS levels, we propose to adapt multimedia streaming to a fluctuating network load and/or client requests, thereby providing adaptive QoS. We describe the simple server and client applications we have implemented to illustrate this adaptation process.},
keywords={QoS,RTS,Internet},
pdf={adaptive quality of service.pdf},
}
</bibtex>
<bibtex>
@inproceedings{352,
author={G.Muntean;L.Murphy},
title={A Novel Feedback Controlled Multimedia Transmission Scheme},
booktitle={International Conference on Telecommunications},
year={2001},
abstract={The number of multimedia transmissions over the existing network infrastructure is continually increasing. This leads to longer periods of network congestion which affects these transmissions and hence their playout. We propose a novel feedback controlled multimedia transmission scheme in order to ensure continuous stream delivery and play-out, even in the case of network congestion. Data transmission and the exchange of control information are done via a doublechannel (TCP and UDP) link. A special protocol (Client Initiated Protocol) has been defined to provide the transmission mechanism with a reduced overhead. We describe both its components, the Client Initiated Streaming Protocol (CISP) used for control and the Client Initiated Transport Protocol (CITP) used for data transmissions. We also present the feedback scheme and describe the server's possible state transitions. A multicast approach is explored and its advantages and disadvantages outlined. We present some experimental results to show the functionality of our scheme.},
keywords={Multimedia,TCP/UDP},
pdf={novel feedback.pdf},
}
</bibtex>
<bibtex>
@inproceedings{353,
author={C.Hava;J.McManis;J.Murphy;L.Murphy},
title={A New Dynamic Web Server },
booktitle={International Conference on Telecommunications},
year={2001},
abstract={The growth of traffic on the Internet and the explosion in the number of Web sites created in recent years make Web server performance an important issue for Web site designers. To improve the server's performance, it is necessary to determine the main factors affecting it before proposing new solutions for Web server design. Here we first present some experimental results on factors which influence Web server performance. We show how the number of concurrent clients accessing the server and the overall network traffic dynamics affect the performance. The details of a Web page’s composition are also studied to determine their effect on performance. Then we describe a new approach for developing a Web server, in which the server takes its performance as the clients see it into account and dynamically generates the requested Web pages. Their content depends on the traffic conditions and client capabilities. Some results are described to show the feasibility of our proposed design.},
keywords={Internet,QoS,Web Server},
}
</bibtex>
<bibtex>
@inproceedings{354,
author={G.Muntean;L.Murphy},
title={Experimental Results for a Feedback-Controlled Multimedia Transmission System},
booktitle={17th IEE UK Teletraffic Symposium},
year={2001},
abstract={Multimedia transmissions over IP networks have increased significantly in recent years. Both user expectations and traffic levels have increased as well. One way to take these into account is for senders to receive and respond to feedback about the quality of their transmissions. We have built a feedback controlled multimedia transmission system, and we have tested and analysed the influence of various factors on transmission performance. This paper presents the results of some of these tests, and suggests some solutions for improving the quality of multimedia transmissions under network congestion.},
keywords={Multimedia,IP},
pdf={experimental.pdf},
}
</bibtex>
<bibtex>
@inproceedings{355,
author={M.Narbutt;L.Murphy},
title={Adaptive Playout Buffering for Audio/Video transmission over the Internet},
booktitle={17th IEE UK Teletraffic Symposium},
year={2001},
abstract={Transmitting real-time audio/video over the Internet is very difficult due to packet loss and jitter. These parameters vary depending on the locations of the senders and receivers, with typical packet loss rates of 0?20% and one-way delays of 5-500 ms. Delay variations occur within and across audio and video streams, complicating the synchronization process. One possibility for reducing jitter involves buffering audio and video packets at the receiver, so that slower packets arrive in time to be played out in the correct sequence at the appropriate times. This paper presents various adaptive playout buffer algorithms that minimize the effect of delay jitter. We evaluate their effectiveness through experiments based on a real network and compare their performance in terms of delay/packet loss ratios. Although the main focus of this paper is the playout buffering for audio, the synchronization between audio and video streams is also specified.Transmitting real-time audio/video over the Internet is very difficult due to packet loss and jitter. These parameters vary depending on the locations of the senders and receivers, with typical packet loss rates of 0?20% and one-way delays of 5-500 ms. Delay variations occur within and across audio and video streams, complicating the synchronization process. One possibility for reducing jitter involves buffering audio and video packets at the receiver, so that slower packets arrive in time to be played out in the correct sequence at the appropriate times. This paper presents various adaptive playout buffer algorithms that minimize the effect of delay jitter. We evaluate their effectiveness through experiments based on a real network and compare their performance in terms of delay/packet loss ratios. Although the main focus of this paper is the playout buffering for audio, the synchronization between audio and video streams is also specified.},
keywords={Internet,Online-Streaming},
pdf={adaptive buffering.pdf},
}
</bibtex>
<bibtex>
@inproceedings{356,
author={N.Cranley;L.Murphy},
title={Adaptive Quality of Service for Streamed MPEG-4 over the Internet},
booktitle={17th IEE UK Teletaffic Symposium},
year={2001},
abstract={Currently multimedia is either downloaded before viewing, or streamed over a network. However, streaming real-time or near real-time applications with a specified Quality of Service (QoS) over the Internet is not yet a solved problem. The Real-time Transport Protocol (RTP) can be used to facilitate streaming, but also has the potential to support QoS. By gathering network statistics during the session and defining different QoS levels, we propose to adapt multimedia streaming to a fluctuating network load and/or client requests, thereby providing adaptive QoS. We describe the simple server and client applications we have implemented to illustrate this adaptation process.},
keywords={RTP,QoS},
pdf={adaptive quality.pdf},
}
</bibtex>
<bibtex>
@inproceedings{465,
author={H.Melvin;L.Murphy},
title={An Investigation into the use of Synchronised Time to Improve VoIP Service },
booktitle={IEI/IEE Symposium on Telecommunications Systems Research },
year={2001},
abstract={This paper presents an overview of work in progress relating to the use of synchronised time in Voice over IP (VoIP) networks. One of the principal limita- tions of conventional IP networks is the best-e�ort service that they provide. In recent years, the In- ternet Engineering Task Force (IETF) have created the multimedia data and control architecture which incorporates protocols such as the Realtime Trans- port Protocol (RTP), RTP Control Protocol (RTCP) and Real Time Streaming Protocol (RTSP). Whilst these protocols assist in delivery of multimedia traÆc, the lack of bounds on end-to-end delay still presents signi�cant problems for interactive applications such as VoIP. The ITU-T recommendation G.114 speci�es that a round-trip-delay of 300ms should not be ex- ceeded and the Plain Old Telephone System (POTS) generally does much better than this. Along with RTP and RTCP, various approaches have been pro- posed and taken to improve the performance of VoIP networks from an interactive viewpoint. These range from sender-based codec measures to network-based policies that di�erentiate between traÆc ows and �- nally to various bu�er schemes at the receiver that balance overall delay with receiver packet loss due to late arrival. This paper summarises much of this work but focuses on receiver-based measures. RTP timestamps are principally used to enable re- ceiver hosts to monitor and react to the inter-packet delay variance (jitter). RTCP packet timestamps fur- ther enable sender hosts to periodically determine round-trip-times (RTT). Such calculations do not re- quire that end host clocks are synchronised. In this paper, a scheme is described whereby syn- chronised time is available to hosts in a VoIP ses- sion. As Global Positioning System (GPS) receivers become increasingly cost-e�ective and always-on In- ternet connections more prevalent, VoIP hosts can avail of synchronised time either via GPS or Network Time Protocol (NTP). This time synchronisation en- ables each host to know precisely the end-to-end de- lays on a packet-by-packet basis. This is a signi�- cant improvement on the present situation whereby sender hosts can periodically determine round-trip- times and thus estimate one-way-delays. Most adap- tive receiver bu�er schemes do not consider such es- timates and are designed to minimise delay at the expense of tolerable packet loss due to late arrival and some distortion of inter-talkspurt silence peri- ods. In many instances, the performance of private IP networks and the localised public Internet will op- erate well within the bounds of G.114. In such sit- uations, a �xed end-to-end delay within the G.114 bounds yet marginally above the actual end-to-end performance would result in a tolerable delay with no late packet loss and no distortion of silence pe- riods. With synchronised time, supporting protocols and receiver-based intelligence, such a system can be implemented.},
keywords={VoIP,IP Networks},
pdf={an investigation.pdf},
}
</bibtex>
<bibtex>
@inproceedings{466,
author={M.Narbutt;L.Murphy},
title={Adaptive Anti-Jitter Mechanism for Multi-Party Conferencing in a H.323 Multi Point Control Unit},
booktitle={IEI/IEE Symposium on Tlecommunications System Research},
year={2001},
abstract={In this paper we propose a mechanism that can support multi-party conferencing. The main objective of this mechanism is to minimize effect of delay jitter. We have tested this mechanism in the Internet using H.323 terminals and H.323 Multipoint Control Unit. Our results show that the playout algorithms traditionally designed to work in the receiving endpoints can also be successfully implemented in the Multipoint Control Unit. As a result one can lower the rate of lost packets due to their late arrival.},
keywords={Delay,Jitter},
pdf={adaptive anti jitter.pdf},
}
</bibtex>

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<bibtex>
@inbook{232,
author={Yang Yu; Vasken Genc; Sean Murphy; Liam Murphy},
title={Network Planning for IEEE 802.16j Relay Networks},
publisher={WiMAX Network Planning and Optimization },
year={2009},
abstract={In this chapter, a problem formulation for determining optimal node location for Base Stations (BSs) and Relay Stations (RSs) in relay-based 802.16 networks is developed. A number of techniques are proposed to solve the resulting Integer Programming (IP) problem - these are compared in terms of the time taken to find a solution and the quality of the solution obtained. Finally, there is some analysis of the impact of the ratio of Base Station (BS)/Relay Station (RS) costs on the solutions obtained. Three techniques are studied to solve the IP problem: (1) a standard branch and bound mechanism, (2) an approach in which state space reduction techniques are applied in advance of the branch and bound algorithm and (3) a clustering approach in which the problem is divided into a number of sub-problems which are solved separately, followed by a final overall optimisation step. These different approaches were used to solve the problem. The results show that the more basic approach can be used to solve problems for small metropolitan areas; the state space reduction technique reduces the time taken to ¯nd a solution by about 50%. Finally, the clustering approach can be used to find solutions of approximately equivalent quality in about 30% of the time required in the first case. After the scalability tests were performed, some rudimentary experiments were performed in which the ratio of BS/RS cost was varied. The initial results show that for the scenarios studied, reducing the RS costs results in more RSs in the solution, while also decreasing the power required to communicate from the mobile device to its closest infrastructure node (BS or RS).},
keywords={relay planning},
}
</bibtex>
<bibtex>
@inbook{159,
author={Moebs, S. and Weibelzahl, S.},
title={Blended Learning: Towards a Mix for SMEs - Stakeholders and their Priorities},
publisher={Blended Learning},
year={2007},
pages={162-173},
abstract={While blended learning seems to be quite suitable for small and medium sized enterprises (SMEs), current uptake of this learning method is low. In this paper we propose a research design to examine the requirements for blended learning in SMEs. It is based on a three-round ranking-type Delphi study. Participants for the panels were carefully selected. Our method takes into account that the area and the term of blended learning are discussed in very different, partially contradicting connotations. For this purpose, we first provide the background of the initial research question and describe our research design. Next, we present preliminary results of the Delphi study and the steps in preparation of round 2. Participants were selected for the online-Delphi and grouped into panels of SME learners, trainers and providers of e-learning as well as learners from large companies as a control group for the SME learners.},
keywords={blended learning, SME, learning technology, Delphi study, Requirements},
pdf={wbl2007_BL4SMEs.pdf},
}
</bibtex>
<bibtex>
@inbook{457,
author={O.Ormond;Gabriel-Miro Muntean},
title={Dynamic Handover in Wireless LAN/MAN Heterogenous Networks},
publisher={Mobile WiMAX:Towards Broadband Wireless Metropolitan Area Networks},
year={2007},
abstract={In future generations of wireless networks, it is expected that different users with various multi-homed personal wireless devices will have the option of accessing their desired services via different available radio access networks. Given the variability of the radio environment properties and user mobility, the availability and characteristics of an access network will change in time and are highly dependent on location. As a result, dynamic reselection of the access network will be a necessary part of the mobility management mechanism (which
maintains the session connectivity as the user moves and/or the available access characteristics change). In their selection of a radio access network customers will consider cost and perceptive quality preferences for the current application and will rely on intelligent network selection decision strategies to aid or automate their choice.},
keywords={Wireless Network,Radio Network},
pdf={dynamic.pdf},
}
</bibtex>
<bibtex>
@inbook{458,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={End User Quality of Experience Aware Personalised in E-Learning},
publisher={Architecture Solutions for E-Learning Systems},
year={2007},
abstract={In the context of new devices and with a variety of network technologies that allow access to the Internet, the providers of e-learning materials have to ensure that the users have a positive experience using their e-learning systems and they are happy to re-use them. Adaptive Hypermedia research aims to provide personalised educational material that ensures a positive learning experience for the end-users. However, user experience is dependent not only on the content served to them, but also on the user perceived performance of the e-learning system. This leads to a new dimension of individual differences between Web users: the end-user Quality of Experience (QoE). We have proposed a solution for Adaptive Hypermedia Systems (AHS) that provides satisfactory end-user QoE through the use of a new QoE layer. This layer attempts to take into account multiple factors affecting QoE in relation to the delivery of a wide range of Web components such as text, images, video, audio.
The effectiveness of our QoE layer has been tested in comparison to a standard educational AHS and the results of these tests are presented in this paper. Different educational-based evaluation techniques such as learner achievement analysis, learning performance assessment, usability survey and correlation analysis between individual student performance and judgment on system usability were applied in order to fully assess the performance of the proposed QoE layer. Results of the tests showed that the use of the QoE layer brought significant improvements in terms of user learning performance, system usability and user satisfaction with the personalised e-learning system while not affecting the user learning achievement
},
keywords={end-user QoE, adaptive hypermedia, e-learning, end-user perceived performance, learning performance },
pdf={end-user.doc},
}
</bibtex>

Pubs:conference

2012-03-09T13:11:50Z

Root:

<bibtex>
@inproceedings{254,
author={Bogdan Ciubotaru; Gabriel–Miro Muntean},
title={Smooth Adaptive Soft Handover Algorithm for Multimedia Streaming over Wireless Networks},
booktitle={IEEE Wireless Communications & Networking Conference (WCNC)},
year={2009},
abstract={Inter-network mobility is achieved by allowing a mobile node to change its point of attachment to the network while preserving connectivity to its corresponding nodes. Most handover solutions proposed in the literature directly change the whole data flow from one network to another relying on only one network to transfer the entire data stream. These solutions involve a certain amount of quality degradation due to increasing loss and delay and suffer in terms of scalability, efficient resource allocation and resilience to different mobile node speeds. This paper proposes the Smooth Adaptive Soft-Handover Algorithm (SASHA) which increases the quality of the multimedia delivery process when performing handover in heterogeneous wireless environment by gracefully transferring the load from one connection to the other. },
keywords={Heterogeneous mobile networks, Handover, Load balance, Multimedia streaming},
pdf={Ciubotaru_Muntean_WCNC_09.pdf},
}
</bibtex>
<bibtex>
@inproceedings{256,
author={Vasile Horia Muntean and Gabriel-Miro Muntean},
title={A Novel Adaptive Multimedia Delivery Algorithm for Increasing User Quality of Experience during Wireless and Mobile E-learning},
booktitle={IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB)},
year={2009},
abstract={Multimedia content is distributed via all types of networks to viewers found in a variety of locations and using different types of devices. Increasing the performance of multimedia stream delivery requires overcoming many technological challenges, all of them having a direct effect on the user perceived quality of experience. The quality of experience influences in turn the quality of any e-learning process. This is as users in general and learners in particular are becoming increasingly quality-aware in their expectations. Therefore delivering a good quality video stream as a part of any e-learning process is very important. This paper proposes a new adaptive multimedia delivery algorithm which can be used in the context of e-learning. The Dynamic Quality Oriented Adaptation Scheme (D-QOAS) adapts the multimedia content sent based on both user preferences and network conditions, while adjusting dynamically its adaptation policy during delivery. Simulation results show that for different user profiles and various network conditions the improvement in end-user perceived quality is significant. Important benefits are obtained in terms of the total number of simultaneous users and in the link utilization, as well as in quality as measured by some video quality metrics.},
keywords={dynamic content adaptation, e-learning, multimedia, rate control, wireless networks},
}
</bibtex>
<bibtex>
@inproceedings{259,
author={Brid Kilbane; Sabine Moebs; Jennifer McManis},
title={Learning Styles or Not? A Classroom Experience},
booktitle={EdTech 2009 - the Irish Educational Technology Users' Conference},
year={2009},
abstract={Secondary Teacher Assistant Researchers (STARs) is a program of Science Foundation Ireland (SFI) that supports research collaboration between secondary school teachers and SFI funded scientists and engineers. The main idea of the program is to disseminate new skills and knowledge to teachers, which can be passed on to their students, by providing them an opportunity to work in a research laboratory. The goal of the project “Social Media to Support Learning Styles of Secondary Students in the Junior Cycle” was to explore whether a blended learning setting consisting of online learning materials matching different learning styles in addition to a face-to-face class results in a significant impact on the learning results.},
keywords={learning styles, blended learning, social media},
pdf={poster_Kilbane_moebs_mcmanis_final_090501.pdf},
}
</bibtex>
<bibtex>
@inproceedings{260,
author={Andreea Molnar; Cristina Hava Muntean},
title={Enhancing Domain Model with Performance Oriented Metadata for Adaptive E-learning Systems },
booktitle={EdTech},
year={2009},
abstract={Due to the increasing complexity of web site navigation, but also as a response to the “one size fits all” approach, adaptation mechanisms have emerged and have started to be used by a large number of on-line educational systems. As educational content may be delivered though various types of networks that differ in characteristics and vary with the time, the quality of the transmitted information is affected. PAMAH (Performance-Aware Multimedia-based Adaptive Hypermedia) proposes to overcome this barrier by taking into consideration in the personalisation process not only the classic learner profile but also the performance of the network connection used by the learner, when rich media content is delivered. This paper focuses on presenting performance oriented metadata required for modelling the educational content and for enhancing the adaptation process. The goal is to provide a personalised media rich content suitable for the learner network connection. },
keywords={Adaptive and personalized e-learning, domain modelling, multimedia },
pdf={Enhancing Domain Model with Performance Oriented Metadata for Adaptive E-learning Systems.pdf},
}
</bibtex>
<bibtex>
@inproceedings{261,
author={Andreea Molnar; Cristina Hava Muntean},
title={Performance Aware and Cost Oriented Adaptive e-Learning Framework},
booktitle={IADIS International Conference e-Learning},
year={2009},
abstract={Nowadays learners have access to multiple wireless networks from the same hand held device challenging them to choose the best network in terms of cost and performance. However, the Internet billing plans are still difficult to understand, predict and control by most users. This paper presents a user oriented adaptive e-learning framework which takes into consideration: (i) the learner profile when content adaptation is done, (ii) user device that can have multiple wireless connections with different characteristics, (iii) how much the learner is willing to pay, and (iv) the network delivery performance. The goal is to ensure that the learner gets educational content that best suits his/her profile and that content will be delivered over the network which assures the best delivery performance, maintaining also a small price for getting the requested information.},
keywords={adaptive and personalised e-learning, wireless connectivity, budget, framework, user modelling},
pdf={Performance Aware And Cost Oriented Adaptive e-Learning Framework.pdf},
}
</bibtex>
<bibtex>
@inproceedings{340,
author={Genc,V.;Murphy,S.;Murphy,J.},
title={System-Level Performance Evaluation of Multi-Cell Transparent Mode Relay 802.16j Systems},
booktitle={IEEE Globecom 2009},
year={2009},
abstract={In this paper, the system capacity of a multi-cell IEEE 802.16j system operating in transparent mode is investigated. A previous published analytical model is used and incorporates interference from neighbouring cells. The model can be used to determine downlink performance under max-min fairness constraints for both sectored and omnidirectional systems with different amounts of relays. The study provides guidelines on the design of 802.16j systems operating in transparent mode – specifically, how to maximise throughput for such systems. It is shown that inter-cell interference from relays is limited in a suburban environment and that relays can deliver significant gains over single hop systems: gains of 30% and 60% can be achieved without and with spatial reuse in an omnidirectional system while 15% and 25% in a sectorised system.},
keywords={IEEE 802.16j, transparent relay, multicell, interference, spatial reuse, performance},
pdf={system level.pdf},
}
</bibtex>
<bibtex>
@inproceedings{341,
author={Holub,V.;Parsons,T.;O'Sullivan,P.;Murphy,J.},
title={Run-Time Correlation Engine for System Monitoring & Testing},
booktitle={IEEE International Conference on Autonomic Computing(ICAC-09)},
year={2009},
abstract={Today’s enterprise applications can produce vast amounts of information both during system testing and in production. Correlation of this information can be difficult as it is generally stored in a range of different event logs, the format of which can be application or vendor specific. Furthermore these large logs can be physically distributed across a number of different locations. As a result it can be difficult to form a coherent understanding of the overall system behaviour. This has implications for a number of domains (e.g. autonomic computing, system testers), where an understanding of the system behaviour at run-time is required (e.g. for problem determination, autonomic management etc.) This paper presents an approach and implementation of run-time correlation of large volumes of log data and symptom matching of known issues in the context of large enterprise applications. Our solution provides for automatic data collection, data normalisation into a common format, run-time correlation and analysis of the data to give a coherent view of system behaviour at run-time and a symptom matching mechanism that can identify known errors in the correlated data on the fly.},
keywords={System Monitoring and Testing, Event Correlation, Event Filtering},
pdf={real time.pdf},
}
</bibtex>
<bibtex>
@inproceedings{342,
author={Fallon,E.;Murphy,L.;Murphy,J.},
title={Optimising Metropolitan Area Wireless Path Selection using Media Independent Handover},
booktitle={International Workshop on Cross Layer Design},
year={2009},
abstract={The Stream Control Transmission Protocol (SCTP) is a transport layer protocol which can support mobility through its multi-homing feature. SCTP's mobility support can be subdivided into 2 areas: path performance evaluation and switch implementation. As a transport layer protocol, SCTP's path performance evaluation is limited by its end-to-end network view. In modern heterogeneous networks, it is likely that the wireless access element of an end-to-end association is the point of performance degradation. SCTP's adherence to protocol boundaries abstracts the precision and meaning of performance metrics. In this paper, we analyze how the emerging cross layer switch management approach, Media Independent Handover (MIH), can be used to optimize path selection for metropolitan area wireless broadband networks. In such an environment line of sight can easily be obstructed, causing temporary path communication failure. We investigate how Received Signal Strength (RSS) can be used as a performance indicator, which triggers MIH path migration events in such a scenario. Results are presented which illustrate that our MIH based approach has significant performance improvement over standard SCTP strategies.},
keywords={cross layer, MIH, SCTP, mobility, WiMax},
pdf={optimising.pdf},
}
</bibtex>
<bibtex>
@inproceedings{343,
author={Nowak,D.;Murphy,J.;Perry,P.},
title={Bandwidth Allocation in DiffServ Enabled Ethernet Passive Optical Networks},
booktitle={IET Communications},
year={2009},
abstract={Ethernet Passive Optical Networks (EPONs) have attracted consider- able attention from industry as they offer a simple, highly flexible and cost effective solution to the problem of providing broadband access to a customer. In this paper, a new approach to bandwidth allocation in EPONs is presented where the Optical Line Terminator (OLT) has full control over the access mechanism. This results in much simpler Optical Network Unit (ONU) architecture. It is shown in this paper that such an OLT-centric architecture offers full support for Differentiated Services and makes enforcement of Service Level Agreements possible. Extensive simulation experiments show that bandwidth allocation algorithms deployed in such a central- ized environment can deliver good performance in terms of average and maximum packet delay. In this paper two new algorithms are introduced that target SLA- aware EPONs and provide a good protection of offered quality of service against interference from other sources.},
keywords={Ethernet,LAN},
pdf={bandwidth allocation.pdf},
pdf={optimising.pdf},
}
</bibtex>
<bibtex>
@inproceedings{449,
author={C.Xu;E.Fallon;Y.Qiao;Gabriel-Miro Muntean;X.Li;A.Hanley},
title={Analysis of Real-Time Multimedia Transmission over PR-SCTP with Failover Detection Delay & Reliablity Level Diffrential},
booktitle={IEEE International Conference on Communication Software & Networks},
year={2009},
abstract={The growing availability of different wireless access technologies provides the opportunity for real-time distribution of multimedia content using multi-homing technology. Investigating the behaviors and quality of such applications under heavy network load is necessary. This paper studies the effect of path failure detection threshold and reliability level on Stream Control Transmission Protocol Partial Reliability Extension (PR-SCTP) performance in symmetric and asymmetric path conditions respectively with different path loss rates. The platform Evalvid-SCTP implemented in the University of Delaware’s SCTP ns-2 module performs the emulation experiment.},
keywords={Real-time; PR-SCTP; Evalvid-SCTP},
}
</bibtex>
<bibtex>
@inproceedings{460,
author={G.Cunningham;P.Perry;J.Murphy;L.Murphy},
title={Seamless Handover of IPTV Streams in a Wireless LAN Network},
booktitle={},
year={2009},
abstract={A robust mechanism to enable seamless handover of streamed IPTV in a WLAN is presented. Handover in a wireless network is usually based on signal strength measurements, but that approach does not consider levels of congestion within the network. Here, the case of stationary nodes with varying levels of network congestion is considered. A scheme that analyses the jitter is used to establish the relationship between congestion and loss in WLANs. This Moving Average of Negative Jitter is used as the basis of a handover scheme which can minimize loss. The handover scheme uses a client with two simultaneous connections to the same server through two separate WLANs, and it is shown that the client can compare the jitter in the two streams to determine which network delivers the best performance; this information is then used to determine when to perform a handover. The proposed scheme is implemented and results are presented that show the successful handover of an RTP over UDP stream in a live WLAN environment. The test scenario used is aimed at “Over-The-Top” service delivery, but the core algorithm is expected to be more broadly applicable.},
keywords={IPTV, Handover, Streamed Video, Wireless LAN1.},
pdf={seamless.pdf},
}
</bibtex>
<bibtex>
@inproceedings{461,
author={S.Fallon;P.Jacob;Y.Qiao;A.Hanley;L.Murphy},
title={Using 802.11 MAC Retransmission for Path Selection in Multi-Homed Transport Layer Protocols},
booktitle={IEEE Globecom},
year={2009},
abstract={The Stream Transmission Control Protocol(SCTP)is a transport layer protocol which can support mobility through its multi-homing feature. One of the key parameters used by SCTP to manage path selection is Retransmission Time Out(RTO).We illustrate that SCTP evaluation of underlying paths using end to end metrics,results is the calculation of excessive RTO for degraded wireless paths.},
keywords={SCTP,RTO,MAC Retransmissions,Mobility},
pdf={using 802.11.pdf},
}
</bibtex>
<bibtex>
@inproceedings{462,
author={C.Lamoriniere;A.Nafaa;L.Murphy},
title={Dynamic Switching Between Adaptive FEC Protocols For Multi-Source Streaming},
booktitle={},
year={2009},
abstract={Multi-source streaming is essential for the design of a large-scale P2P streaming architecture. In this paper, we focus on improving the dependability of multi-source video streaming as an alternative to the more prevalent point-to-point streaming. We have designed and implemented a dynamic FEC (D-FEC) protocol for multi-source video streaming. Our D-FEC protocol has the ability to dynamically switch between 4 different FEC techniques to adapt to varying network conditions. A comprehensive performance evaluation was performed with a full-scale system prototype that gives insights into the behavior of the different adaptive FEC schemes, and shows the feasibility of the concept of switching FEC schemes during a streaming session. Guidelines are given in order to best design a FEC protocol switching strategy taking into account the experienced loss rate, the loss burstiness, and the original video stream rate.},
keywords={P2P,FEC,Multi-Source Streaming},
pdf={dynamic switching.pdf},
}
</bibtex>
<bibtex>
@inproceedings{463,
author={Y.Yu;S.Murphy;L.Murphy},
title={Interference Aware Relay Station Location Planning for IEEE 802.16j Mobile Multi-Hop Relay Networks},
booktitle={12th ACM International Conference on Modeling Analysis & Simulation of Wireless & Mobile Systems},
year={2009},
abstract={In this paper, an interference aware algorithm for multi-cell Relay Station (RS) location planning problem is proposed in order to investigate the capacity gains possible using transparent mode 802.16j. The study focuses on the problem of determining the best choice of locations for RS from a given set of candidate sites - Base Station (BS) and Subscriber Station (SS) locations are assumed given. The proposed algorithm evaluates each RS based on the channel conditions of the links between the RS and its surrounding Subscriber Stations(SS) and the throughput gain it could deliver, taking into account co-channel interference. The performance statistics were collected over a large amount of experiments with many different configurations, including Base Station(BS) antenna types, number of candidate RS sites, RS transmitting power, with/without spatial reuse, etc. The results can be divided into two sections. Firstly, the algorithm was tested for optimality and scalability and was shown to perform well compared to classical Integer Programming solution techniques. Secondly, the results generated by the algorithm when applied to different scenarios were analyzed. Results show that using spatial reuse could achieve a much higher throughput gain, 3-5 time, then without using spatial reuse, although sectorised BS antenna limits the separation of co-channel RSs in a sector. The results demonstrate the characteristics of the trade-off between number of RSs and throughput gain for different configurations.},
keywords={IEEE 802.16j, Spatial Reuse, Network Planning, Relay Station Location Problem},
pdf={interference aware.pdf},
}
</bibtex>
<bibtex>
@inproceedings{468,
author={Scotton, J.; Moebs, S,; McManis, J.; Cristea, A.I.},
title={A Case Study on Merging Strategies for Authoring QoE-based Adaptive Hypermedia},
booktitle={ECTEL 2009},
year={2009},
abstract={This paper describes recent work on strategy merger development in the authoring process of adaptive hypermedia. The goal of a merging strategy is to break a complex adaptation decision into a number of simpler ones which may be reused more easily and applied in different orders. To demonstrate the proposed method we present an example case study and sample strategies written in the LAG language. The case study is based on a recently proposed model for Quality of Experience in e-learning. This model exposes the complex interaction between a number of factors affecting QoE and hence presents a good candidate for the application of a strategy merger. Finally some evaluation points are identified, a conclusion is drawn and next steps are outlined.},
keywords={LAG, Quality of Experience, Quality of Service, Multimedia Learning, Educational Adaptive Hypermedia, Adaptation, Strategy merger},
pdf={A3H09Paper_FinalPostReviewChanges_ScottonMoebsMcManisCristea.pdf},
}
</bibtex>
<bibtex>
@inproceedings{469,
author={Andreea Molnar; Cristina Hava Muntean},
title={Billing Issues when Accessing Personalised Educational Content},
booktitle={China-Ireland International Conference on Information and Communications Technologies (CIICT 2009)},
year={2009},
abstract={The increased affordability of mobile devices combined with the availability of the latest wireless technologies have made mobile devices an attractive tool for learning. Nowadays learners can choose between multiple wireless networks with different characteristics, belonging to the same or to different mobile operators. Unfortunately, the Internet billing plans are still difficult to predict and control by most users. This paper presents an algorithm which aims to determine the best network, from a list of available ones (in terms of price), for delivering the selected educational content.},
keywords={cost, mobile data billing plan, mobile learning, adaptive and personalised learning},
}
</bibtex>
<bibtex>
@inproceedings{470,
author={Andreea Molnar; Cristina Hava Muntean},
title={QoE-MOT – A Learner Quality of Experience- Oriented Authoring Tool},
booktitle={European Conference on Technology Enhanced Learning, A3H: 7th International Workshop on Authoring of Adaptive and Adaptable Hypermedia},
year={2009},
abstract={This paper introduces Quality of Experience My Online Teacher (QoE-MOT), a user quality of experience oriented version of the generic authoring tool MOT. QoE-MOT is an authoring tool which enables the creation of performance-aware adaptive courses, by adapting the educational content to the learner network conditions. MOT was developed based on LAOS, a complex five layer authoring model. In similar fashion, QoE-MOT was constructed following the QoE-LAOS, a learner quality of experience oriented authoring model. This paper illustrates how an adaptive educational course has been enhanced with performance oriented metadata and how this metadata and QoE parameters are used during the adaptation process.},
keywords={Authoring tool, Adaptive e-learning, LAOS, QoE, MOT, LAG},
pdf={QoE-MOT.pdf},
}
</bibtex>
<bibtex>
@inproceedings{109,
author={Sabine Moebs; Jennifer McManis},
title={A Learner, is a Learner, is a User, is a Customer - So what exactly do you mean by Quality of Experience?},
booktitle={Adaptive Hypermedia and Adaptive Web-based Systems},
year={2008},
abstract={An e-learner’s Quality of Experience (QoE) is informed by previous experiences as a learner, a user of computer/web-based systems, and a customer. This paper surveys different concepts for Quality of Experience (QoE) from different areas such as psychology, internet marketing, web engineering, systems and product development as well as philosophy of education. They are summarized into a proposal for a definition of Learner QoE in adaptive multimedia e-learning systems. A number of factors are identified that are likely to impact on QoE. We propose a <st1:place w:st="on">Delphi</st1:place> study to be used to provide an initial ranking of the importance of these factors. Additional user testing will be required to confirm the findings of this study. },
keywords={adaptive hypermedia, quality of experience, educational philosophy},
pdf={ah_ws6_moebs_mcmanis.pdf},
}
</bibtex>
<bibtex>
@inproceedings{162,
author={C. Thorpe; S. Murphy; L. Murphy},
title={Analysis of Variation in IEEE802.11k Channel Load Measurements for Neighbouring WLAN Systems},
booktitle={ICT Mobile Summit},
year={2008},
abstract={This paper focuses on analysing the variation in IEEE802.11k channel load measurements for neighbouring WLAN systems. The channel load functionality was implemented in the QualNet simulation tool, and several scenarios were configured for testing. The effects of different numbers of active systems with different traffic patterns were examined. The results obtained indicate significant variation in channel load values calculated by different stations experiencing different levels of interference. This variation leads us to question the usefulness of a single channel load measurement; hence considerable care must be taken when using and interpreting such measurements. },
keywords={IEEE802.11k, Channel Load Measurements, Interference},
pdf={ICTMobileSummit_Paper_Camera_Ready.pdf},
}
</bibtex>
<bibtex>
@inproceedings{183,
author={Sabine Moebs},
title={A Learner, is a Learner, is a User, is a Customer - QoS-based Experience-aware Adaptation},
booktitle={ACM Multimedia},
year={2008},
abstract={This paper describes an outline of the doctoral thesis work concerning adaptation policies towards quality of experience (QoE) in performance-aware adaptive multimedia e-learning systems. QoE is considered to be mainly affected by the psychological concept of flow and learning-related factors. In turn, for multimedia systems, these factors can be heavily influenced by quality of service (QoS). In an ideal world, QoS would not be an issue and content optimally tailored to a user’s needs could always be perfectly delivered. Unfortunately, delivery conditions are not always ideal, and it may be infeasible to deliver certain multimedia content such as high quality video while maintaining an acceptable QoS. The goal of this research is to balance the constraints imposed by QoS restrictions with the requirements of flow and learning in order to produce the highest possible QoE for the learner using an adaptive multimedia system.},
keywords={Algorithms, Performance, Design, Human Factors, QoE, QoS, Flow, Learning},
pdf={smoebs_multimedia2008_ds.pdf},
}
</bibtex>
<bibtex>
@inproceedings{184,
author={S. Moebs; J. McManis},
title={ADAPTIVE SOCIAL CONNECTEDNESS IN A MULTIMEDIA E-LEARNING ENVIRONMENT},
booktitle={China-Ireland Conference on ICT (CIICT)},
year={2008},
abstract={Adaptive hypermedia systems are beneficial to e-learners in tailoring content to individual characteristics such as prior knowledge, learning preferences, etc. However, unlike popular non-adaptive learning management systems such as Moodle and Blackboard they do not support social connectedness by allowing communication with other learners. This can lead to feelings of isolation amongst learners and ultimately learner demotivation. Enabling communication has been shown to improve cohesion within a learner group and allows a tutor to monitor learner participation and intervene before learners become disengaged. This paper outlines a stand-alone component connect! for the selection of multimedia communication tools in adaptive e-learning systems to support social connectedness. In addition to the already proven benefits of supporting social interaction, attaching such a module to an adaptive hypermedia system allows us to introduce the novel feature of tailoring the communication method to the individual needs of the learner. We draw on research in the area of media ecology to assist us in making our decisions.},
keywords={adaptive systems, social connectedness},
pdf={moebs_mcmanis_adaptive_social_connectedness_final.pdf},
}
</bibtex>
<bibtex>
@inproceedings{186,
author={Seung-Bum Lee;Gabriel-Miro Muntean;Alan F. Smeaton},
title={Smart PIN: Utility-based Replication and Delivery of Multimedia Content to Mobile Users in Wireless Networks.},
booktitle={IEEE International Symposium on Broadband Multimedia Systems and Broadcasting 2008: Mobile and Handheld Systems for Entertainment on the Go},
year={2008},
abstract={Next generation wireless networks rely on heterogeneous connectivity technologies to support various rich media services such as personal information storage, file sharing and multimedia streaming. Due to users mobility and dynamic characteristics of wireless networks, data availability in collaborating devices is a critical issue. In this context Smart PIN was proposed as a personal information network which focuses on performance of delivery and cost efficiency. Smart PIN uses a novel data replication scheme based on individual and overall system utility to best balance the requirements for static data and multimedia content delivery with variable device availability due to user mobility. Simulations show improved results in comparison with other general purpose data replication schemes in terms of data availability.},
keywords={Content management, Non-real-time service, Interactive systems, Mobile systems, Portable and handheld devices},
}
</bibtex>
<bibtex>
@inproceedings{187,
author={Seung-Bum Lee;Gabriel-Miro Muntean;Alan F. Smeaton},
title={User-centric Utility-based Data Replication in Heterogeneous Networks.},
booktitle={IEEE International Conference on Communications, Workshop on Digital Television and Mobile Multimedia Broadcasting (ICC 2008)},
year={2008},
abstract={Information overload and convergence of devices aggravate the difficulties of accessing data distributed among various user devices especially when this is performed by mobile users and over heterogeneous wireless networks. Existing data replication systems help increase the performance of the distributed data system, but they do not consider users different levels of interest in various pieces of data and neither heterogeneous wireless connectivity issues. This paper presents the Smart Personal Information Network (Smart PIN), a performance and cost-aware personal information network which uses a novel usercentric utility-based data replication scheme to exchange content automatically, based on both network performance and user interests. The proposed user-centric data replication scheme s evaluation, through simulation, shows improved results in comparison with existing solutions.},
keywords={ Data replication, Utility Function, Heterogeneous Network},
}
</bibtex>
<bibtex>
@inproceedings{193,
author={Bogdan Ciubotaru; Gabriel-Miro Muntean},
title={M3S - Multimedia Mobility Management and Load Balancing in Wireless Broadcast Networks},
booktitle={China-Ireland International Conference on Information and Communications Technologies 2008 (CIICT 2008)},
year={2008},
pages={515-521},
abstract={Wireless local-area networks represent a viable broadband Internet access solution for enterprise, residential and public areas. Due to its short range radio, multiple wireless access points are necessary to cover a certain physical area. The tendency of mobile users to group in certain areas of interest and of mobile devices to connect to the access point with the highest signal strength determines the overall network load to be highly unbalanced. To overcome this issues which drastically affects user bandwidth share as well as the efficiency of network resource utilization, special load balancing techniques has to be employed. This paper presents the Multimedia Mobility Management System (M3S), a quality oriented mobility management framework which aims at maximizing user perceived multimedia quality by efficiently distributing the traffic load over all the communication resources available. Simulation based testing results are presented, outlining the performance of M3S against other load balancing techniques which rely on mobile device re-association with least congested access points.},
keywords={wireless broadcast networks, load balance, mobility management},
pdf={Ciubotaru_Muntean_CIICT08.pdf},
}
</bibtex>
<bibtex>
@inproceedings{218,
author={J. Fitzpatrick, S. Murphy, M. Atiquzzaman, J. Murphy},
title={ECHO: A Quality of Service based Endpoint Centric Handover scheme for VoIP},
booktitle={Wireless Communications and Networking Conference (WCNC)},
year={2008},
abstract={Existing terminal oriented handover mechanisms capable of meeting the strict delay bounds of real time applications such as VoIP do not consider the QoS of candidate handover networks. In this paper ECHO – a QoS based handover solution for VoIP– is proposed. ECHO is endpoint centric and does not require any network support; it leverages the SCTP transport protocol. ECHO incorporates network metrics that directly affect VoIP quality into the handover decision process. A dynamic variant of the ITU-T E-Model is used to calculate how the network metrics map to a user perceived voice quality metric known as the MOS. The MOS value is then used to make handover decisions between each of the available access networks. The results show that the addition of the QoS capabilities significantly improves the handover decisions that are made.},
keywords={ECHO, QoS, E-Model, SCTP, Handover, VoIP},
}
</bibtex>
<bibtex>
@inproceedings{223,
author={Yang Yu;Sean Murphy;Liam Murphy},
title={A Clustering Approach to Planning Base Station and Relay Station Locations in IEEE 802.16j Multi-hop Relay Networks},
booktitle={Proc. IEEE International Conference on Communications (ICC 2008)},
year={2008},
abstract={In this paper, a clustering approach to solve a network planning problem for 802.16j relay networks is considered. Our clustering approach consists of three basic steps: (1) divide the nodes into k distinct clusters, (2) solve the planning problem separately for each cluster, and (3) perform a final optimization to reduce issues arising at cluster boundaries. Simulation results show that our approach is more efficient than existing approaches: solutions of equivalent quality can be found in 40% of the time. Thus our technique can be used to solve larger problems with similar hardware, or similar size problems in less time.},
keywords={network planning,802.16j,Wimax,relay network,clustering},
}
</bibtex>
<bibtex>
@inproceedings{224,
author={Yang Yu;Sean Murphy;Liam Murphy},
title={Planning Base Station and Relay Station Locations in IEEE 802.16j Multi-hop Relay Networks},
booktitle={Proc. 2nd IEEE Broadband Wireless Access Workshop, colocated with IEEE CCNC 2008},
year={2008},
abstract={In this paper, a problem formulation for determining optimal node location for Base Stations (BSs) and Relay Stations (RSs) in relay-based 802.16 networks is developed. The formulation results in an Integer Programming problem. A small modification to the original model is also considered in which the state space is reduced by limiting which nodes can be associated with which. Standard branch and bound techniques are used to solve the problem. The key findings of the paper are that standard techniques can be used to find solutions to problems of small metropolitan scale or for areas within a larger city.},
keywords={network planning,802.16j,Wimax,relay network},
}
</bibtex>
<bibtex>
@inproceedings{230,
author={Vasken Genc; Sean Murphy; John Murphy},
title={An Interference-Aware Analytical Model for Performance Analysis of Transparent Mode 802.16j Systems},
booktitle={Broadband Wireless Access Workshop co-located with GLOBECOM},
year={2008},
abstract={In this paper, an interference-aware analytical model of IEEE 802.16j systems operating in transparent mode is described. The model can be used to determine the throughput gain that can be achieved by 802.16j relay- based systems under a max-min fairness constraint in which the difference between the data rate delivered to all subscribers is minimized. Two variants of the model are considered – one in which there is no spatial reuse and one in which there is spatial reuse. The study finds that this variant of 802.16j system can deliver significant gains over traditional single-hop access systems: 40% in the case in which there is no spatial reuse and up to 80% when spatial reuse is realised.},
keywords={IEEE 802.16j, optimisation problem, performance gain, transparent multihop relay},
pdf={camerayready-BWA08.pdf},
}
</bibtex>
<bibtex>
@inproceedings{231,
author={Vasken Genc; Sean Murphy; John Murphy},
title={Performance Analysis of Transparent Relays in 802.16j MMR Networks},
booktitle={WiOpt},
year={2008},
abstract={A simulation study of the performance of transparent mode relay-based 802.16j systems is described. The study focuses on the gain in throughput that is possible in omnidirectional relay systems and increases in signalling requirements that arise due to the multihop network architecture. The study finds that the introduction of transparent mode relays cannot deliver improved throughput for a substantial part of the coverage area of a Base Station (BS) – only approximately half of the total area covered by the BS can benefit from throughput enhancement. Further, the study shows that 802.16j based systems require significant signalling overhead, with almost twice that of 802.16e in the cases studied. Finally, the study demonstrates that in a topology with users uniformly distributed within the BS cell coverage, the maximum throughput increase on the downlink that can be achieved is relatively low. Much further work is necessary to realise useful gains from these systems.},
keywords={MMR, transparent multihop relay, performance, omnidirectional antenna},
pdf={wiopt08-cameraready.pdf},
}
</bibtex>
<bibtex>
@inproceedings{331,
author={Parsons,T.;Mos,A.;Murphy,J.;Trofin,M.;Gschwind,T.},
title={Extracting Interactions in Component Based Systems},
booktitle={IEEE Transactions on Software Engineering},
year={2008},
abstract={Monitoring, analysing and understanding component based enterprise software systems are challenging tasks. These tasks are essential in solving and preventing performance and quality problems. Obtaining component level interactions which show the relationships between different software entities is a necessary prerequisite for such efforts. This paper focuses on component based Java applications, currently widely used by industry. They pose specific challenges while raising interesting opportunities for component level interaction extraction tools. We present a range of representative approaches for dynamically obtaining and using component interactions. For each approach we detail the needs it addresses, and the technical requirements for building an implementation of the approach. We also take a critical look at the different available implementations of the various techniques presented. We give performance and functional considerations and contrast them against each other by outlining their relative advantages and disadvantages. Based on this data, developers and system integrators can better understand the current state of the art and the implications of choosing or implementing different dynamic interaction extraction techniques.},
keywords={Distributed objects, components, containers, tracing.},
pdf={extracting.pdf},
}
</bibtex>
<bibtex>
@inproceedings{332,
author={Alocci,I.;Murphy,S.;Nafaa,A.;Murphy,J.},
title={Development of an IEEE 802.11s Simulation Model for QualNet},
booktitle={Networking & Electronic Commerce Research Conference},
year={2008},
abstract={In this work, an initial variant of an 802.11s simulation model for the QualNet simulator is described. The tool builds on the existing QualNet 802.11 model by adding capabilities suitable for mesh networking. More specifically, the model provides support for propagation of beacon frames in mesh networks and link establishment procedures by which nodes attach to the network.},
keywords={Networking,QOS},
pdf={development.pdf},
}
</bibtex>
<bibtex>
@inproceedings{333,
author={Qiao,Y.;Fallon,E.;Murphy,L.;Murphy,J.;Hanley,A.},
title={Path Selection of SCTP Fast Retransmission in Multi-Homed Wireless Environments},
booktitle={13th IFIP International Conference on Personal Wireless Communications},
year={2008},
abstract={In heterogeneous wireless network environments, network connections of a device may have a significant differential. This paper studies the effect of path bandwidth differential on the performance of fast retransmission strategies in Multi-homing environments. It identifies that fast retransmission on an alternate path may cause receive buffer blocking when path bandwidth differential is significant and the receive buffer is limited. A theoretical model is proposed for selecting retransmission path during the fast retransmission phase, which is based on receive buffer and path conditions. The model is verified through simulations with various path differentials.},
keywords={Wireless Communication},
pdf={path selection.pdf},
}
</bibtex>
<bibtex>
@inproceedings{335,
author={Fallon,E.;Murphy,L.;Murphy,J.},
title={An Analysis of the Performance of an MIH Based Switch Strategy for Heterogenous Network Mobility},
booktitle={IEEE 17th IST Mobile & Wireless Communications Summit},
year={2008},
abstract={The increasingly ubiquitous deployment of wireless networks has created significant opportunities for mobile application developers. The availability of highcapacity, low financial cost networks has the potential to enable mobile application developers to offer feature-rich end-user-oriented product offerings. Standardisation efforts such as Media Independent Handover (MIH) will support this trend by providing developers with a detailed view of the financial cost and performance capabilities of available wireless and mobile networks. Even with the increasingly pervasive deployment of Wireless LAN (WLAN), it is unlikely those mobile applications will exclusively utilise WLAN networks, as many are deployed without consideration of seamless network mobility. In the scenario where WLAN coverage gaps exist, it will be necessary to utilise mobile networks such as UMTS as a communication bridge. In such an environment, the mobility support provided by multi-homed protocols such as the Stream Control Transmission Protocol (SCTP) has significant potential. This paper investigates how MIH performance characteristics - in particular the Received Signal Strength (RSS) from a WLAN Access Point (AP) - can be used to optimise SCTP switch performance. Results indicate that in certain situations there is a performance problem with utilising a "retransmit on same path" approach to lost packet retransmission when the primary path is explicitly set, as would be the case with MIH. Careful configuration of the RSS threshold for switchover is shown to alleviate the problem.},
keywords={SCTP, WLAN, Network Migration},
pdf={an analysis.pdf},
}
</bibtex>
<bibtex>
@inproceedings{436,
author={B.Ciubotaru;Gabriel-Miro Muntean},
title={M3S-Multimedia Mobility Management & Load Balancing in Wireless Broadcast Networks},
booktitle={IET Chine-Ireland International Conference on Information & Communications Technology},
year={2008},
abstract={Wireless local-area networks represent a viable broadband Internet access solution for enterprise, residential and public areas. Due to its short range radio, multiple wireless access points are necessary to cover a certain physical area. The tendency of mobile users to group in certain areas of interest and of mobile devices to connect to the access point with the highest signal strength determines the overall network load to be highly unbalanced. To overcome this issues which drastically affects user bandwidth share as well as the efficiency of network resource utilization, special load balancing techniques has to be employed. This paper presents the multimedia mobility management system (M3S), a quality oriented mobility management framework which aims at maximizing user perceived multimedia quality by efficiently distributing the traffic load over all the communication resources available. Simulation based testing results are presented, outlining the performance of M3S against other load balancing techniques which rely on mobile device re-association with least congested access points},
keywords={Multimedia,Wireless Networks,Mobile Communication},
}
</bibtex>
<bibtex>
@inproceedings{446,
author={C.Xu;Gabriel-Miro Muntean;E.Fallon;A.Hanley;F.Karayel},
title={A Balanced Tree-based Strategy for Unstructured Media Distribution in P2P Networks},
booktitle={IEEE International Conference on Communication},
year={2008},
abstract={Most research on P2P multimedia streaming assumes that users access video content sequentially and passively. Unlike P2P live streaming in which the peers start playback from the current point of streaming when they join the streaming session, in P2P video-on-demand streaming VCR-like operations such as forward, backward, and random-seek have to be supported. Providing this level of interactive streaming service in a P2P environment is a significant challenge. This paper proposes a Balanced Binary Tree-based strategy for Unstructured video-ondemand distribution in P2P networks (BBTU). BBTU assumes videos can be divided into several segments which can be fetched from different peers. BBTU involves two steps: 1) balance binary tree construction based on a prefetching algorithm in order to support interactivity; 2) unstructured video dissemination over network based on gossip protocol, which is the overlay for video distribution. Analysis and simulation show how BBTU is an efficient interactive streaming solution in P2P environment.},
keywords={P2P video-on-demand; interactivity; balanced},
pdf={a balanced.pdf},
}
</bibtex>
<bibtex>
@inproceedings{447,
author={C.XU;Gabriel-Miro Muntean;E.Fallon;X.Li},
title={DONET-VOD:A Hybrid Overlay Solution for Efficient Peer-to-Peer Video on Demand Services},
booktitle={IEEE International Conference on Multimedia & Expo(ICME)},
year={2008},
abstract={The existing DONet-based approach uses successfully a random gossip algorithm for scalable live video streaming. This pure mesh overlay network-based solution may lead to unacceptable latency or even failure of VCR operations in Video-on-Demand (VoD) services where nodes usually have different playing offsets, across a wide range. This paper proposes DONet-VoD which enhances DONet in order to address issues related to VoD delivery and VCR operations. In DONet-VoD, DONet principle is employed for the video distribution over the overlay network and a novel algorithm which uses a multi-way tree structure and extra prefetching buffers at the nodes is proposed to support efficient VoD operations. Video segments are prefetched and stored in a distributed manner in the nodes’ prefetching buffer along the tree. The cooperation between DONetbased video delivery and the tree-located multimedia components enable multimedia streaming interactive commands to be performed efficiently. This paper presents and discusses the prefetching scheme, details the cooperation procedure, and then analyses the performance of the proposed DONet-VoD},
keywords={Peer-to-peer, VoD, prefetching, multiway},
pdf={donet.pdf},
}
</bibtex>
<bibtex>
@inproceedings{448,
author={C.Xu;Y.Qiao;E.Fallon;Gabriel-Miro Muntean},
title={Comparitive Study of Real-Time Multimedia Transmission over Multi-Homing Transport Protocols},
booktitle={IEEE /IFIP International Conference on Management of Multimedia Networks & Services},
year={2008},
abstract={The availability of multimedia applications suitable for deployment using 3G and GPRS networks has led to a requirement for end-to-end quality of service. More efficient mechanisms are needed in order to provide the required end user quality of service in wireless data networks. This paper investigates the performance implications of transmitting real-time multimedia content over a multi-homed transport protocol in a manner which is tolerant of network failure. It evaluates video quality with different retransmission policies combined with various path failure detection thresholds, path bandwidths, delays and loss rate conditions through Partial Reliable Stream Control Transmission Protocol (PRSCTP). A solution called Evalvid-SCTP, which is a trace driven simulation of MPEG-4 video over SCTP, was designed to achieve the performance evaluation.},
keywords={PR-SCTP, Multi-homing, MPEG-4 Video, Congestion Control},
pdf={comparitive study.pdf},
}
</bibtex>
<bibtex>
@inproceedings{185,
author={Seung-Bum Lee;Gabriel-Miro Muntean;Alan F. Smeaton},
title={Cost-oriented Context and Content Data Pair Delivery in Smart PIN},
booktitle={China-Ireland International Conference on Information and Communications Technologies},
year={2007},
pages={97-204},
abstract={With evolutions of wireless technologies and advances in mobile services, ubiquitous devices have huge acquired and storing data which requires metadata for user to handle easily. For this purpose, this paper introduces Smart PIN - a novel performance and cost-oriented, context-aware personal information network. Smart PIN architecture includes network components, service components and management components. At the service components, there should be consideration for service discovery, service composition, data replication management and data pair transfer. Among these issues, this paper proposes a novel scheme for efficient delivery of context and content data based on pull and push scheme controlling logical and physical cost function.},
keywords={Context-awareness, Data replication, Cost-effectiveness, Wireless PAN},
}
</bibtex>
<bibtex>
@inproceedings{216,
author={S. Murphy, M. Atiquzzaman, J. Fitzpatrick, J. Murphy},
title={Terminal-oriented solutions for seamless service delivery via heterogeneous radio access networks (Invited Paper)},
booktitle={Sarnoff Symposium 2007},
year={2007},
abstract={In this paper, options for providing seamless service delivery to mobile terminals via heterogeneous radio access networks are considered. Despite its current popularity, the Mobile IP solution for mobility management of mobile hosts is discounted due to problems associated with introducing the required network infrastructure and poor handover performance. Rather, the solution described here comprises of a number of key technologies working together. More specifically, the paper argues that the most appropriate solution comprises of the following: adaptive applications, an abstraction layer between application and transport layer, an intelligent transport layer with multi-homing and multi-path support and a means to obtain current state information about each of the available access networks. While work has been ongoing on each of these individual components little has been done to address how they can all be integrated and consider how they may perform in the context of different radio access technologies, potentially operated by different entities. This paper attempts to address some of these issues.},
keywords={Heterogeneous wireless access networks, Handover, Mobile Networking},
}
</bibtex>
<bibtex>
@inproceedings{217,
author={J. Fitzpatrick, S. Murphy, M. Atiquzzaman, J. Murphy},
title={Evaluation of VoIP in a Mobile Environment using an SCTP based Handoff Mechanism},
booktitle={IST Mobile Summit},
year={2007},
abstract={In parallel with the growth of VoIP services, a large number of manufacturers have begun to develop multimode devices capable of connecting to multiple wireless access networks simultaneously. These multimode terminals have, in principle, the capability to support seamless handover between different radio access networks. One handover solution that utilises the IP diversity which these multimode devices can deliver is SIGMA. SIGMA is a promising end-to-end transport layer handover solution based on SCTP. The objective of this paper is to investigate if SIGMA is capable of providing seamless handover of VoIP calls without degradation in voice quality. To achieve this, we developed a Linux based testbed on which we implemented a VoIP client and server using SIGMA handoff . Each voice call uses the G.711 voice codec over RTP. PR-SCTP is used in place of the traditional UDP as the transport layer protocol. SIGMA based handover was used during full duplex voice calls between the client and server. The ITU-T E-Model has been used to calculate the voice quality during the handover. Results show that SIGMA can be used as a seamless handover mechanism for VoIP without any impact on voice quality.},
keywords={SCTP, VoIP, SIGMA, Seamless Handover},
}
</bibtex>
<bibtex>
@inproceedings{233,
author={Odd Inge Hillestad; Andrew Perkis; Vasken Genc; Sean Murphy; John Murphy},
title={Adaptive H.264/MPEG-4 SVC video over IEEE 802.16 Broadband Wireless Networks},
booktitle={Packet Video},
year={2007},
abstract={In this paper we present a solution for delivering streaming video-on-demand to subscribers via an 802.16 broadband wireless access network. The solution leverages the forthcoming H.264/AVC Scalable Video Coding (SVC) scheme and a mechanism to perform rate adaptation based on monitoring changes to the amount of flow traffic in the network at any time. A simulation-based approach is used to determine how the system performs in a rural deployment. Results show that the scheme provides high utilization of the wireless access system, at over 96%. Further, it maintains smooth transmission rate for the video applications, and ensures that no interruptions in continuous video playback occur during the streaming session. Lastly, a comparison with single-layer H.264/AVC is performed, showing how the proposed solution performs better with respect to both system utilization and the fact that no clients suffer interruptions in continuous playback.},
keywords={IEEE 802.16, video streaming, scalable video coding},
}
</bibtex>
<bibtex>
@inproceedings{322,
author={Ormond,O.;Murphy,J.;Muntean,G.},
title={Dynamic Network Selection in Wireless LAN/MAN Heterogenous Networks},
booktitle={Mobile WiMAX:Toward Broadband Wireless Metropolitan Area Networks},
year={2007},
abstract={In future generations of wireless networks, it is expected that different users with various multi-homed personal wireless devices will have the option of accessing their desired services via different available radio access networks. Given the variability of the radio environment properties and user mobility, the availability and characteristics of an access network will change in time and are highly dependent on location. As a result, dynamic reselection of the access network will be a necessary part of the mobility management mechanism (which maintains the session connectivity as the user moves and/or the available access characteristics change). In their selection of a radio access network customers will consider cost and perceptive quality preferences for the current application and will rely on intelligent network selection decision strategies to aid or automate their choice. These dynamic selection strategies will need to take into account different dynamic, and sometimes conflicting, metrics},
keywords={Wireless Communication},
pdf={dynamic network.pdf},
}
</bibtex>
<bibtex>
@inproceedings{323,
author={Carrig,B.;Denieffe,D.;Murphy,J.},
title={A Non-Elevated Scheduling Solution for First Person Shooter Games in IEEE 802.11 Networks},
booktitle={IEEE Globecom 2007},
year={2007},
abstract={First Person Shooter (FPS) games are a popular online gaming genre played predominately over wired networks. FPS games are highly interactive and have stringent delay requirements. However, the explosive growth in wireless LAN (WLAN) deployment has seen an increase in the use of such networks for gaming purposes. The varied performance of the IEEE 802.11 MAC Distributed Coordination Function (DCF) has tended to make WLANs unsuitable for FPS games. The IEEE 802.11e standard introduces Quality of Service (QoS) mechanisms including Enhanced Distributed Channel Access (EDCA) allowing prioritization of competing flows. Using the NS- 2 simulator, we evaluate the capability of 802.11g and 802.11e WLANs to support Quake IV games traffic in the presence of web traffic. We compare the results achieved using EDCA with those achieved by a non-elevated differentiated services scheduler known as Best Effort with Loss Trade-off (BELT). We find that the BELT scheduler compares favorably with EDCA in this context.},
keywords={Online Gaming,LAN,QOS},
pdf={non elevated.pdf},
}
</bibtex>
<bibtex>
@inproceedings{324,
author={Carrig,B.;Denieffe,D.;Murphy,J.},
title={A Congestion-only Charging Mechanism for Multiplayer Gaming in Diffrentiated Service Networks},
booktitle={IEEE Globecom 2007},
year={2007},
abstract={In networks based on the Di®erentiated Services (Di®Serv) architecture, users may be presented the opportunity to choose their Assured Forwarding (AF) class. Users will attempt to maximize their Consumer Surplus (CS) in such an environment. They can increase their CS by choosing the lowest cost AF class that satis¯es their Quality of Service (QoS) requirements. Previously the authors have proposed an algorithm known as Consumer Surplus Maximization (CSM) [2]. Although this algorithm improves CS for users, widespread adoption of the algorithm can provoke network instability. If many users switch classes at once, degradation on one AF class can easily propagate. The likelihood of such an occurrence can be reduced by replacing ¯xed per- byte or per-packet charges associated with individual AF classes with a lightweight Congestion-only Charging (CoC) pricing mechanism. An additional charge is only applied to packets that receive discernible bene¯t from belonging to a particular class. We present simulation results from a networking scenario where users connect across a single Di®Serv domain to engage in a multiplayer First Person Shooter (FPS) game.},
keywords={Pricing, Quality of Service, Di®Serv},
pdf={congestion only.pdf},
}
</bibtex>
<bibtex>
@inproceedings{325,
author={Murphy,L.;Noonan,J.;Perry,P.;Murphy,J.},
title={An Application-quality based Mobility Management Scheme},
booktitle={9th International Conference on Mobile & Wireless Communication Networks},
year={2007},
abstract={Experimental results are presented for end-point controlled handover of a stream of voice-like packet data traffic between two independent wireless networks. The handover was achieved by using a version of the Stream Control Transmission Protocol (SCTP) that had been modified to monitor link quality and switch the primary connection to the “best” quality link available, where quality is evaluated in terms of application performance. The results clearly show that mobility management based solely on received signal strength is not suitable for wireless systems with contention-based access policies such as WiFi.},
keywords={Mobile Communication, Network Testing, Packet Radio, Wide area networks, Wireless LAN, Handover, VoIP, Call Quality},
pdf={application-quality.pdf},
}
</bibtex>
<bibtex>
@inproceedings{326,
author={Carrig,B.;Denieffe,D.;Murphy,J.},
title={Supporting First Person Shooter Games in Wireless Local Area Networks},
booktitle={IEEE 18th International Symposium on Personal,Indoor & Mobile Radio Communications},
year={2007},
abstract={First Person Shooter (FPS) games are a popular online gaming genre played predominately over wired networks. FPS games are highly interactive and have stringent delay requirements. However, the explosive growth in wireless LAN (WLAN) deployment has seen an increase in the use of such networks for gaming purposes. The varied performance of the IEEE 802.11 MAC Distributed Coordination Function (DCF) has tended to make WLANs unsuitable for FPS games. The IEEE 802.11e standard introduces Quality of Service (QoS) mechanisms including Enhanced Distributed Channel Access (EDCA) allowing prioritization of competing flows. Using the NS-2 simulator, we evaluate the capability of 802.11g and 802.11e WLANs to support Quake IV games traffic in the presence of web traffic. We compare the results achieved using EDCA with those achieved by a non-elevated differentiated services scheduler known as Best Effort with Loss Trade-off (BELT). We find that the BELT scheduler compares favorably with EDCA in this context.},
keywords={Online Gaming,LAN,QOS,IEEE 802.16},
pdf={supporting first.pdf},
}
</bibtex>
<bibtex>
@inproceedings{327,
author={Carrig,B.;Denieffe,D.;Murphy,J.;OSE,D.},
title={Congestion-only Charging: A Novel PricinG Mechanism for use in Diffrentiated Service Networks},
booktitle={ACM 4th International Conference on Heterogenous Networking for Quality,Reliablity,Security & Robustness,Qshine2007},
year={2007},
abstract={In networks based on the Di®erentiated Services (Di®Serv) architecture, users may be presented the opportunity to choose their Assured Forwarding (AF) class. Users will attempt to maximize their Consumer Surplus (CS) in such an environment. They can increase their CS by choosing the lowest cost AF class that satis¯es their Quality of Service (QoS) requirements. Previously the authors have proposed an algorithm known as Consumer Surplus Maximization (CSM) [2]. Although this algorithm improves CS for users, widespread adoption of the algorithm can provoke network instability. If many users switch classes at once, degradation on one AF class can easily propagate. The likelihood of such an occurrence can be reduced by replacing ¯xed per- byte or per-packet charges associated with individual AF classes with a lightweight Congestion-only Charging (CoC) pricing mechanism. An additional charge is only applied to packets that receive discernible bene¯t from belonging to a particular class. We present simulation results from a networking scenario where users connect across a single Di®Serv domain to engage in a multiplayer First Person Shooter (FPS) game.},
keywords={Pricing, Quality of Service, DiffServ},
pdf={congestion novel.pdf},
}
</bibtex>
<bibtex>
@inproceedings{328,
author={Qiao,Y.;Fallon,E.;Murphy,L.;Murphy,J.;Hanley,A.;Zhu,X.;Matthews,A.;Conway,E.},
title={SCTP Performance Issue on Path Delay Diffrential },
booktitle={WWIC 5th International Conference on Wired/Wireless Internet Communications},
year={2007},
abstract={This paper studies the effect of path delay on SCTP performance. It focuses on the SCTP fast retransmit algorithm and demonstrates that the performance in the current retransmission strategy will degrade acutely when the secondary path delay is less than the primary path delay at a certain level. The performance degradation is due to the disordered SACKs and constant congestion window size during the fast retransmit phase. Some modifications aimed at these problems are proposed and evaluated. This paper also identifies that the cause of the performance degradation in SCTP is a result of the single path configuration oriented design of the current fast retransmit algorithm. Several fast retransmission strategies are evaluated for different path delay and bandwidth configurations.},
keywords={SCTP, Multi-homing, Retransmission strategy, Path difference.},
pdf={sctp.pdf},
}
</bibtex>
<bibtex>
@inproceedings{329,
author={Hnetynka,P.;Murphy,J.},
title={Deployment of Java Based Components in Embedded Environment},
booktitle={International Conference Applied Computing},
year={2007},
abstract={Component-based development has brought the benefits of easier reuse, integration and rapid development into the software engineering process. Many contemporary component-based platforms (e.g. EJB, CCM, SOFA, Fractal) are implemented in Java because of Java features such as platform independence, dynamic loading, type safety, and others. Another reason is that Java becomes more and more ubiquitous as devices like mobile phones, PDAs, etc. embed the Java implementation. However in the area of embedded systems, applications are usually still monolithic and therefore hard to maintain and reuse. On the other hand, the embedded Java platform has several important limitations, which prevent straightforward reuse of component-based platforms. In this paper, we present how to overcome these limitations and use contemporary component platforms for developing applications for embedded systems. We demonstrate the approach on the SOFA 2.0 component platform. The paper shows that the only parts of the SOFA 2.0 platform, which have to be adapted, are the deployment process and the runtime environment. The rest of the platform suits for development for embedded systems without any change and allows for benefiting from SOFA 2.0 features like behavior validation, multiple communication styles, separated control part of components, etc.},
keywords={Hierarchical components, deployment, embedded environment, Java.},
pdf={deployment.pdf},
}
</bibtex>
<bibtex>
@inproceedings{330,
author={Carrig,B.;Denieffe,D.;Murphy,J.},
title={A User Controlled Priority Selection Strategy for Multiplayer Games},
booktitle={IEEE 4th Consumer Communications & Networking Conference},
year={2007},
abstract={Future Quality of Service (QoS) aware networks, such as those based on the Differentiated Services (DiffServ) architecture, will provide users with the opportunity to assign a priority to the traffic they receive and generate. Different priorities will entail different per-byte or per-packet charges. To aid users operating within such an environment, a priority selection strategy is required. In this paper, we propose a priority selection strategy based on the concept of Consumer Surplus (CS), which is the positive difference between utility or the user’s willingness-to-pay and cost. We then evaluate this strategy in a networking scenario where a user is involved in a multiplayer Counterstrike game, in which different priorities may be assigned to the downstream traffic. A utility curve, applicable to a First Person Shooter (FPS) game like Counterstrike, is presented. Using simulation results we show that for varied traffic loads, the CS strategy offers comparable application performance to that of always selecting the highest priority, but at a reduced cost to the user.},
keywords={Qos,DiffServ,Online Gaming},
pdf={user-controlled.pdf},
}
</bibtex>
<bibtex>
@inproceedings{435,
author={Z.Fratczak;Gabriel-Miro Muntean;K.Collins},
title={Electronic Monitoring of Nutritional Components},
booktitle={Information & Telecommunication Technology},
year={2007},
abstract={Obesity and other diseases related to unhealthy diet are problems of near epidemic proportion and become a growing issue every year. This paper presents a solution to this issue by proposing the use of a computer application that is able to suggest the appropriate products related to one’s diet, and to keep track of nutritional intake. The paper also describes the principle of the solution, system architecture and implementation and presents testing results. If the application’s instructions are followed by users it is expected that an optimal diet will be achieved resulting in users good health.},
keywords={Healthy diet, e-health, utility function, nutrition control},
pdf={electronic.pdf},
}
</bibtex>
<bibtex>
@inproceedings{440,
author={J.Adams;Gabriel-Miro Muntean},
title={Power Save Adaptation Algorithm for Multimedia Streaming to Mobile Devices},
booktitle={IEEE International Conference on Portable Information Devices},
year={2007},
abstract={Batteries have not followed the exponential technological improvements of other mobile device related hardware, such as CPU, memory and wireless networking. Battery power often introduces significant limitations to the use of mobile devices and their applications, including those involved in multimedia streaming that have significant high power requirements. This paper proposes a power save adaptation algorithm for mobile multimedia streaming that aims to increase streaming time given limited battery power resources. The multimedia streaming process is divided into three stages: data reception, decoding and playing and power saving solutions for each of these stages are proposed. These power save mechanisms are then combined to give the power save algorithm. Preliminary tests results show that significant increases in battery lifetime have been achieved when the power save mechanisms proposed in this paper are used.},
keywords={Algorithm,Multimedia Streaming,Mobile Devices},
pdf={power save.pdf},
}
</bibtex>
<bibtex>
@inproceedings{441,
author={E.Casey;Gabriel-Miro Muntean},
title={A Mechanism for Greediness Management whenStreaming Multimedia to Portable Devices},
booktitle={IEEE International Conference on Portable Information Devices},
year={2007},
abstract={The majority of streaming solutions use rate adaptaion based on congestion avoidance mechanisms that try to obtain as much bandwidth as possible from the limited network resources. This is good if we assume that all clients have equal requirements. However this is rarely the case as devices have unique characterstics ( e.g. screen size, screen resolution, location etc) that influence streaming related parameters & consequently the experience obtained by the end user.Due to the inherent greediness of streaming protocols & lack of knowledge about the characterstics of the users devices, this may result in certain devices receiving higher bandwidth share than they actually need & others not receiving enough,affecting the users perceived quality. Therefore there is a need to allow for client diffrentiation in order to provide an acceptable service for all cliemts,taking their device characterstics into account.This paper proposes a Greediness Control Algorithm(GCA),a specially designed application layer solution that tunes the greediness of the multimedia streaming based on client priority, to make more efficient use of the wireless network and increase the overall user perceived quality.},
keywords={Algorithm,Multimedia,Portable Devices},
pdf={mechanism.pdf},
}
</bibtex>
<bibtex>
@inproceedings{442,
author={Gabriel-Miro Muntean;N.Cranley},
title={User Quality of Experience-Aware Multimedia Streaming over Wireless Home Area Network},
booktitle={IEEE Vehicular Technology Conference},
year={2007},
abstract={For multimedia streaming over wireless networks, there is a trade-off between the capacity of the wireless links and the end-user perceived-quality, which can be affected by the compression scheme used, content characteristics and adaptation algorithm (if any). In this paper, this trade-off is investigated for streaming various motion content multimedia over an IEEE 802.11b-based Wireless-Home Area Network using the Quality-Oriented Adaptation Scheme (QOAS). QOAS performance is compared to that of a non-adaptive scheme when using MPEG-2 and MPEG-4 encoding in terms of average end-user perceived quality, number of streaming sessions concurrently supported, loss rate, delay, jitter and total throughput. Simulation results show that by using QOAS and MPEG-4 encoded streams a much higher number of concurrent streams are supported at an average quality above “good” level on the ITU-T five-point quality scale in comparison with other situations. In this case all the other streaming performance parameters were also significantly better.},
keywords={Adaptive video streaming, Wireless Home Area Network, grading scheme, end-user perceived quality.},
pdf={user quality.pdf},
}
</bibtex>
<bibtex>
@inproceedings{443,
author={J.Adams;Gabriel-Miro Muntean},
title={Adaptive Buffer Power Save Mechanism for Mobile Multimedia Streaming},
booktitle={IEEE International Conference on Communication},
year={2007},
abstract={Wireless networks are becoming a part of everyday life for many people. When a mobile device has wireless LAN capability, multimedia content can be streamed over a wireless network to that device. However, a major disadvantage of all mobile devices is their limited battery lifetime. Multimedia streaming puts extra pressure on the battery, causing it to discharge faster. In some cases, streaming tasks cannot be completed purely because the battery of the device becomes fully discharged, which causes significant user dissatisfaction. Consequently, it is necessary to devise mechanisms to enable longer battery lifetime in order to support complex applications such as those involving mobile multimedia streaming. This paper proposes an Adaptive-Buffer Power Save mechanism (AB-PSM) for increasing the battery life of mobile devices during multimedia streaming. This increase is achieved by controlling how and when data is sent over a wireless LAN. AB-PSM introduces an additional buffer which hides data from the station it is intended for, allowing it to return to sleep and consequently saving power. Data is eventually delivered in one of the station’s following attempts to receive it. Tests involving AB-PSM have been performed and show good results in terms of significant increases in battery lifetime. The comparison between AB-PSM and the IEEE 802.11 legacy power save mechanism shows important increases in battery lifetime of more than 100%.},
keywords={Wireless Network,Mobile Communications},
pdf={adaptive buffer.pdf},
}
</bibtex>
<bibtex>
@inproceedings{444,
author={T.Casey;Gabriel-Miro Muntean;D.Denieffe},
title={Influence of Mobile User Velocity on Data Transfer in a Muti-Network Wireless Environments},
booktitle={9th International Conference on Mobile & Wireless Communication Networks},
year={2007},
abstract={Heterogeneous wireless environments are now a reality in many urban areas. Designing and deploying a wireless network in such an environment is complicated by the unpredictable propagation paths of radio signals and by the unpredictable behaviour of the network users themselves. Network simulation and modelling can be used to assist in the design process. However, in order for simulation models to be effective they must be realistic. Efforts have been made to render simulation models more realistic through the analysis of real world wireless networks and through the examination and evaluation of existing simulation models. The most fundamental characteristics of a mobile user are their mobility, and the speed at which they move. The various velocities used in simulation models are unrealistic with respect to pedestrian behaviour in urban environments. In addition, the possible influence of mobile user velocity on the amount of data transferred by the user is not considered. In this paper we examine the influence of a mobile user’s velocity on throughput in a wireless network using a range of realistic velocities.},
keywords={heterogeneous wireless network environment,},
pdf={influence.pdf},
}
</bibtex>
<bibtex>
@inproceedings{445,
author={Gabriel-Miro Muntean},
title={Effect of Delivery Latency,Feedback Frequency & Network Load on Adaptive Multimedia Streaming},
booktitle={IEEE 32nd Local Computer Neworks Conference },
year={2007},
abstract={As video on demand systems gain popularity, it seems likely that the desire to serve a high number of customers from limited network resources could lead to a degradation of the endusers’ perceived quality. Quality-Oriented Adaptation Scheme (QOAS) balances the need for high quality with increased network utilization when streaming multimedia. QOAS requires client-side monitoring of some transmission-related parameters, grading of the end-user’s quality and feedback that informs the server about the received quality. In response to this feedback, the server adjusts the streaming process in order to maximize the end-user perceived quality in the current conditions. This paper studies the effect of delivery latency and feedback frequency on quality-oriented adaptive multimedia streaming. It also shows how high end-user perceived quality is maintained in the presence of different types of background traffic while recording a significant increase in link utilization and a very low loss rate.},
keywords={Adaptive video streaming, grading scheme, end-user},
pdf={effect of delivery.pdf},
}
</bibtex>
<bibtex>
@inproceedings{452,
author={Gabriel-Miro Muntean;N.Cranley},
title={Resource Efficient Quality-Oriented Wireless Broadcasting of Adaptive Multimedia Content},
booktitle={IEEE Trans. on Broadcasting},
year={2007},
abstract={The performance of multimedia stream delivery is influenced by encoding scheme, streaming solution and network conditions. This paper studies the performance of multimedia streaming when using the Quality-Oriented Adaptive Scheme (QOAS) over an IEEE 802.11b Wireless LAN and compares it to that achieved when using other solutions that do not consider end-user quality in their delivery process such as TFRC, LDA+, and non-adaptive schemes. The performance is assessed in terms of average end-user perceived quality, number of concurrent streaming sessions, loss rate, delay, jitter and total throughput when streaming MPEG-4 encoded content. Simulation results show that the QOAS out-performs these other streaming solutions in all aspects of network delivery. QOAS can support a greater number of concurrent streaming sessions at a higher average quality. In addition, for the same number of clients QOAS achieved a higher average end-user quality, as well as better network delivery streaming performance parameters.},
keywords={Adaptive multimedia streaming, end-user quality},
pdf={rsource.pdf},
}
</bibtex>
<bibtex>
@inproceedings{170,
author={C. Thorpe; S. Murphy; L. Murphy},
title={Seamless Handover in Heterogeneous Radio Access Networks},
booktitle={IT&T},
year={2006},
abstract={This paper provides a detailed discussion of the problem of Seamless Handover in Heterogeneous Radio Access Networks. Brief descriptions of several wireless access technologies are included to provide some background information and to illustrate the importance of solving the seamless handover problem for network subscribers. Several approaches to providing a handover solution have been proposed, some of which will be described and compared, in order to indicate possible directions for continuing to search for a seamless handover solution. Various problems are present in the existing solutions, and are discussed in this paper. These problems are significant enough to warrant further investigation in the handover area, and leave scope for modifications and improvements.},
keywords={Seamless Handover, Heterogenous Networks, SCTP},
pdf={christina-itt06-cameraReady.pdf},
}
</bibtex>
<bibtex>
@inproceedings{161,
author={C. Thorpe; L. Murphy},
title={A Survey of Seamless Handover in Heterogeneous Radio Access Networks},
booktitle={ACM/IEEE International Symposium on Modeling, Analysis and Simulation of Wireless and Mobile Systems},
year={2006},
abstract={This paper provides a detailed discussion of the problem of Seamless Handover in Heterogeneous Radio Access Networks. Several approaches to providing a handover solution have been proposed, some of which will be described and compared, in order to indicate possible directions for continuing to search for a seamless handover solution. Various problems are present in the existing solutions, and are discussed in this paper. },
keywords={Seamless Handover, Heterogenous Networks, SCTP},
pdf={Christina-MSWIM-Oct-2006.pdf},
}
</bibtex>
<bibtex>
@inproceedings{213,
author={J. Fitzpatrick, S. Murphy and J. Murphy},
title={An Approach to Transport Layer Handover of VoIP over WLAN},
booktitle={CCNC},
year={2006},
abstract={In this paper a transport layer handover mechanism for Voice over Internet Protocol (VoIP) using the Stream Control Transmission Protocol (SCTP) is proposed. This handover mechanism utilizes the multi-homing feature of SCTP to allow connection to multiple wireless networks. Each available wireless network is probed with simulated VoIP data to obtain network performance metrics. Handover decisions are made based on the Mean Opinion Score (MOS) calculated from the ITU-T E-Model for voice quality assessment using the obtained measurements. Implementation and simulations were carried out using the NS2 network simulator. The results show the MOS obtained using the proposed handover mechanism on IEEE 802.11b WLAN access points (APs) under varying load conditions. High correlation is shown between the MOS from the proposed handover scheme and the MOS experienced by a VoIP node present in the network. A simulation showing an SCTP endpoint handover between AP’s is presented.},
keywords={SCTP, E-Model, VoIP, Handover, Heterogeneous Networks},
}
</bibtex>
<bibtex>
@inproceedings{215,
author={J. Fitzpatrick, S. Murphy, J. Murphy},
title={RTS/CTS Based Endpoint Admission Control for VoIP Over 802.11e},
booktitle={MMNS},
year={2006},
abstract={In this paper an endpoint-based admission control mechanism for VoIP over WLAN is proposed. The mechanism operates by first measuring the utilisation of the channel and comparing this to a pre-determined threshold, if the channel utilisation exceeds this threshold, the call is rejected. One important aspect of the mechanism is that it can operate in the presence of hidden terminals. This is done by using the Request-to-Send/Clear-to-Send WLAN signalling to determine channel utilisation. The scheme is designed to be flexible; it can operate with heterogeneous data rates, with varying traffic types and in the presence of legacy 802.11 nodes. The scheme was developed and evaluated using the Qualnet network simulator. An empirical approach was used to determine appropriate admission thresholds. Then, simulations were performed to demonstrate the successful operation of the scheme.},
keywords={Call Admission Control, VoIP, 802.11e, RTS/CTS},
}
</bibtex>
<bibtex>
@inproceedings{311,
author={Carrig,B.;Denieffe,D.;Murphy,J.},
title={A Relative Delay Minimization Scheme for Multiplayer Gaming in Diffrentiated Services Network},
booktitle={ACM SIGCOMM Workshop on Network & System Support for Games},
year={2006},
abstract={Multiplayer gaming over the Internet continues to grow in popularity, despite a lack of Quality of Service (QoS) mechanisms. Future QoS-aware networks such as those based on the Differentiated Services (DiffServ) framework will provide an opportunity for gamers to enhance their game-playing experience. An important QoS metric for networked games is a user’s delay relative to the delay of other users. In this paper, we propose a Relative Delay Minimization (RDM) algorithm for use in DiffServ environments. Simulation results are described and presented showing that the algorithm can reduce the Relative Delay Variation (RDV) between users in a DiffServ environment.},
keywords={Network Games, Relative Delay, DiffServ, QoS},
pdf={a relative delay.pdf},
}
</bibtex>
<bibtex>
@inproceedings{312,
author={Noonan,J.;Perry,P.;Murphy,J.},
title={End-point Synchronisation & Handover For Multi-homed Services},
booktitle={IEE Proceedings-Communications},
year={2006},
abstract={It is proposed to implement a synchronised routing table at the transport layer, referred to as an Association Routing Table (ART), to improve the performance of multi-homed transport protocols. An algorithm is described that ensures that the routing tables can be synchronised, which is then used to implement a handover mechanism. The ART is implemented within SCTP. It is shown that by using a synchronised ART, it is possible to implement failover in cases where standard SCTP cannot, con¯gurations are more resilient to network errors, and it is possible to perform a handover without any network support.},
keywords={Multi-homing, routing, transport layer, SCTP, handovers},
pdf={end point-sychronization.pdf},
}
</bibtex>
<bibtex>
@inproceedings{313,
author={Hillestad,O.I.;Perkis,A.;Genc,V.;Murphy,S.;Murphy,J.},
title={Delivery of On-Demand Video Services in Rural Areas via IEEE 802.16 Broadband Wireless Access Networks},
booktitle={ACM 2nd Workshop on Wireless Multimedia Networking & Performance Modelling },
year={2006},
abstract={A simulation study of delivery of streaming video on-demand via IEEE 802.16 based technologies is described. A number of scenarios are simulated which are representative of rural area deployments of such technologies. The study finds that IEEE 802.16 can support up to 9/10 simultaneous users streaming typical cinematic video content in CIF resolution, 24 frames/s, at average rates of around 750 kbps. Further, the study demonstrates the utility of H.264/AVC Scalable Video Coding (SVC) and a buffer-based congestion control algorithm in an adaptive video streaming solution.},
keywords={IEEE 802.16, video streaming, scalable video coding},
pdf={delivering of on demand.pdf},
}
</bibtex>
<bibtex>
@inproceedings{314,
author={Ormond,O.;Muntean,G.;Murphy,J.},
title={Evaluation of an Intelligent Utility-Based Strategy for Dynamic Wireless Network Selection},
booktitle={Autonomic Management of Mobile Multimedia Services},
year={2006},
abstract={In the case of next generation wireless networks, different users with various multi-homed personal wireless devices will aim to exploit the full potential of the choice of services and applications available over different radio access networks. In their selection of a certain radio access network consumers will consider money and delay preferences for the current application and will rely on intelligent network-selection decision strategies to aid them in their choice. This paper describes the evaluation of an intelligent utility-based strategy for network selection in a multi-access network situation for transfer of large non real-time data files. A number of scenarios are examined which compare the proposed network selection strategy against other possible strategies. Test results show how by using this network selection strategy significant benefits in terms of combined average delay and cost per file transferred as well as transfer efficiency are obtained.},
keywords={Heterogeneous Wireless Networks, Multi-homed Radio Terminals, User-centric Network Selection.},
pdf={evaluation.pdf},
}
</bibtex>
<bibtex>
@inproceedings{315,
author={Parsons,T.;Mos,A.;Murphy,J.},
title={Non-Intrusive End to End Run-time Path Tracing for J2EE Systems},
booktitle={IEE Proceedings-Software},
year={2006},
abstract={An end-to-end runtime path-tracing approach for J2EE systems has been introduced. The approach is non-intrusive and thus does not require instrumentation of middleware or application source code. The implementation of the system has been realised in the COMPAS Java end-to-end monitoring tool that extends and integrates a number of open source projects. The first set of results shows the performance overhead associated with the tool. Further results show the portability of this approach, by applying it to a number of different application server implementations. Finally, it is also shown that runtime paths collected by the implementation can be used for reasoning about the overall system structure and design of complex enterprise applications.},
keywords={IEEE ,Server},
pdf={non-intrusive.pdf},
}
</bibtex>

Pubs:journal

2012-03-09T13:11:12Z

Root:

<bibtex>
@article{484,
author={Frank A. Zdarksy, Sebastian Robitzsch, Albert Banchs},
title={Security Analysis of Wireless Mesh Backhauls for Mobile Networks},
journal={Journal of Network and Computer Applications},
year={2010},
pages={--},
volume={In Press},
abstract={Radio links are used to provide backhaul connectivity for base stations of mobile networks, in cases in which cable-based alternatives are not available and cannot be deployed in an economic or timely manner. While such wireless backhauls have been predominantly used in redundant tree and ring topologies in the past, mobile network operators have become increasingly interested in meshed topologies for carrier-grade wireless backhauls. However, wireless mesh backhauls are potentially more susceptible to security vulnerabilities, given that radio links are more exposed to tampering and given their higher system complexity.

This article extends prior security threat analyses of 3rd generation mobile network architectures for the case of wireless mesh backhauls. It presents a description of the security model for the considered architecture and provides a list of the basic assumptions, security objectives, assets to be protected and actors of the analysis. On this foundation, potential security threats are analyzed and discussed and then assessed for their corresponding risk. The result of this risk assessment is then used to define a set of security requirements. Finally, we give some recommendations for wireless mesh backhaul designs and implementations following these requirements.},
keywords={Security analysis, Wireless mesh backhauls, Mobile networks},
pdf={2010 - Zdarsky, Robitzsch, Banchs.pdf},
}
</bibtex>
<bibtex>
@article{244,
author={Seung-Bum Lee;Gabriel-Miro Muntean;Alan F. Smeaton},
title={Performance-aware Replication of Distributed Pre-recorded IPTV Content},
journal={IEEE Transactions on Broadcasting Special Issue},
year={2009},
pages={-},
volume={(in press)},
abstract={Video recording in IPTV systems is a promising service that provides time-shifted services in relation to storing TV content closer to user devices such as set-top boxes. Existing approaches do not support collaboration between nodes which have correlated contents, a fact that can affect the performance of the overall system. To make this service more interactive and proactive, this paper presents the architecture using the Smart Personal Information Network (Smart PIN) as a novel performance-based content sharing network for IPTV content which uses a user-centric utility-based Multimedia Data Replication Scheme (MDRS). This allows the exchange of data based on both network performance and user interest in exchanged multimedia content in order to achieve ef?cient content sharing. The proposed solution is evaluated through extensive simulations and results show much improved behaviour in comparison with two other existing general purpose data replicat on schemes.},
keywords={IPTV, Data replication, Content management, Peer-to-peer},
}
</bibtex>
<bibtex>
@article{253,
author={Bogdan Ciubotaru; Gabriel-Miro Muntean},
title={SASHA - A Quality-Oriented Handover Algorithm for Multimedia Content Delivery to Mobile Users},
journal={IEEE Transactions on Broadcasting Special Issue},
year={2009},
pages={-},
volume={(in press)},
abstract={The convergence of the existing network access technologies to a common IP-based architecture and the increase in popularity of accessing video content over the Internet makes IPTV a promising solution for media and entertainment industries. Additionally, video content delivery to the increasingly popular mobile devices over heterogeneous wireless networks makes IPTV even more appealing. However the distribution of multimedia content over heterogeneous wireless networks to mobile devices involves significant technical challenges related to mobility management and quality of service provisioning. The existing solutions do not consider quality of service as a decision making parameter for mobility management in general and handover management in particular.
This paper proposes the Smooth Adaptive Soft Handover Algorithm (SASHA), a novel quality-aware approach to handover based on load balancing among different networks using a comprehensive, Quality of Multimedia Streaming (QMS), function for decision making. SASHA represents the handover management solution at the core of the more comprehensive Multimedia Mobility Management System (M3S), a quality oriented mobility management framework for multimedia applications which maximizes user perceived quality by efficiently exploiting all available communication resources.
Simulation-based testing results are presented, outlining the performance of SASHA in different mobility scenarios. The evaluation is performed for different number of nodes performing handover simultaneous and for various situations in terms of networks’ overlapping area. The results shown indicate how SASHA outperforms other three mobility management solutions in terms of quality, scalability and resilience to the dynamics of the networks’ overlapping area.
},
keywords={Multimedia streaming, IPTV, Heterogeneous networks, Mobility, Handover},
pdf={Ciubotaru_Muntean_IPTV.pdf},
}
</bibtex>
<bibtex>
@article{338,
author={Fitzpatrick,J.;Murphy,S.;Atiauzzaman,M.;Murphy,J.},
title={Using Cross-Layer Metrics to Improve the Performance of End-to-End Handover Mechanisms},
journal={Computer Communication Preprint Online},
year={2009},
pages={13 Pages},
volume={10.1016},
abstract={Network centric handover solutions for all IP wireless networks usually require modifications to network
infrastructure which can stifle any potential rollout. This has led researchers to begin looking at alterna-
tive approaches. Endpoint centric handover solutions do not require network infrastructure modification,
thereby alleviating a large barrier to deployment. Current endpoint centric solutions capable of meeting
the delay requirements of Voice over Internet Protocol (VoIP) fail to consider the Quality of Service (QoS) that will be achieved after handoff. The main contribution of this paper is to demonstrate that QoS aware
handover mechanisms which do not require network support are possible. This work proposes a Stream
Control Transmission Protocol (SCTP) based handover solution for VoIP called Endpoint Centric Handover
(ECHO). ECHO incorporates cross-layer metrics and the ITU-T E-Model for voice quality assessment to
accurately estimate the QoS of candidate handover networks, thus facilitating a more intelligent handoff
decision. An experimental testbed was developed to analyse the performance of the ECHO scheme.
Results are presented showing both the accuracy of ECHO at estimating the QoS and that the addition
of the QoS capabilities significantly improves the handover decisions that are made.},
keywords={Echo,SCTP,VoIP,E-Model,Sigma},
pdf={using cross.pdf},
}
</bibtex>
<bibtex>
@article{339,
author={Qiao,Y.;Fallon,E.;Murphy,L.;Murphy,J.;Hanley,A.;Shi,Z.},
title={Transmission Scheduling for Multihomed Transport Protocols with Network Failure Tolerance},
journal={Telecommunication Systems Journal},
year={2009},
pages={10 pages},
volume={40},
abstract={In heterogeneous network environments, the
network connections of a multi-homed device may
have significant bandwidth differential. For a multihomed
transmission protocol designed for network
failure tolerance, such as SCTP, path selection
algorithms for data transmission drastically affect
performance. This article studies the effect of path
bandwidth differential on the performance of
retransmission strategies in multi-homing
environments. It identifies that fast retransmission on
an alternate path may cause receive buffer blocking
when path bandwidth differential is significant and the
receive buffer is limited. A theoretical model is
proposed for selecting retransmission path during the
fast retransmission phase, based on receive buffer and
path conditions. From these observations and analysis
results, this article proposes that path selection
strategies for transmitting new data and retransmitted
data should be decoupled. A new path selection
scheme is proposed and evaluated through SCTP
simulations.},
keywords={Multi-homing, Transmission Protocol, SCTP},
pdf={transmission.pdf},
}
</bibtex>
<bibtex>
@article{408,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={Open Corpus Architecture for Personalised Ubiquitous e-Learning},
journal={Personal & Ubiquitous Computing },
year={2009},
pages={197-205},
volume={13},
abstract={As the e-learning area matures, there are a growing number of e-learning content providers that produce and distribute material that covers a large range of topics, differs in quality and is represented in various formats. Lately, different devices and various network technologies allow extensive user access to educational content almost anywhere, anytime and from any device. Ubiquitous e-learning has the potential to provide continuous and context-based, educational material to human learners anytime, anywhere and on any device. Since each person has different expectations related to the content, the performance of the delivery and display of that content, it is desirable for an ubiquitous e-learning environment to provide user-oriented personalisation of e-learning material. However very often there are multiple sources of e-learning material at various web locations (open corpus resources) that cover the same topic, but differ in terms of quality, formatting and even cost. It is very difficult for learners to select the content that best suits their interests and goals, characteristics of the device used and delivery network as well as their cost budget. This paper proposes an innovative ubiquitous e-learning environment called Performance-based E-learning Adaptive Cost-efficient Open Corpus frameworK (PEACOCK) that provides support for the selection and distribution of personalised e-learning rich media content (e.g. multimedia, pictures, graphics and text) to e-learners such as it will best suit users’ interests and goals, meet their formatting preferences and cost constraints, while considering the limitations introduced by the end-user devices and the delivery networks to the user. PEACOCK’s main goal is to maximise the users’ e-learning experience and increase their learning satisfaction and learning outcome.
},
keywords={Adaptive e-learning systems - User-oriented personalisation - Cost-efficiency - Ubiquitous e-learning environment },
pdf={open corpus.pdf},
}
</bibtex>
<bibtex>
@article{456,
author={C.Xu;Gabriel-Miro Muntean;E.Fallon;A.Hanley},
title={Distributed Storage-Assisted Data-Driven Overlay Network for P2P VoD Services},
journal={IEEE Trans. on Broadcasting},
year={2009},
pages={1-10},
volume={55},
abstract={Providing VCR-like operations in Peer-to-Peer (P2P)
environments is a significant challenge. This paper proposes a distributed
Storage-assisted Data-driven overlay Network (SDNet)
to support P2P Video-on-Demand (VoD) services. It integrates
two networks: a Data-driven Overlay Network (DONet) and a
multi-way tree. DONet is enhanced and used for the routine video
distribution based on the buffer overlapping mechanism and
gossip protocol. A novel algorithm which uses a multi-way tree
structure and extra pre-fetching buffers at the nodes is proposed
to support efficient VoD operations. Videos are divided into uniform
segments, pre-fetched and stored in a distributed manner
along the tree topology. The cooperation between DONet-based
video delivery and the tree-located multimedia components enable
multimedia streaming interactive commands to be performed
efficiently. This paper presents and discusses the structure of
SDNet and the distributed storage scheme and details the cooperation
procedure. Simulation-based testing results show how the
proposed SDNet is an efficient interactive streaming solution in a
P2P environment.},
keywords={DONet, multi-way tree, P2P VoD, VCR-like.},
pdf={distributed.pdf},
}
</bibtex>
<bibtex>
@article{475,
author={Arturo Azcorra; Thomas Banniza; David Chieng; John Fitzpatrick; Dirk von-Hugo; Marek Natkaniec; Sebastian Robitzsch; Frank Zdarsky},
title={Supporting carrier grade services over wireless mesh networks: The approach of the European FP-7 STREP CARMEN [Very Large Projects]},
journal={IEEE Communications Magazine},
year={2009},
pages={14-16},
volume={47},
abstract={CARMEN is a three-year Specific Targeted Research Project (STREP) funded by the European Commission within the 7th Framework Program. The CARMEN access network will complement existing access technologies by exploiting low cost mesh networking techniques, thus minimizing deployment and maintenance costs. The CARMEN architecture introduces an abstraction layer that hides the specifics of the underlying access technology providing an abstract interface on top of which higher layers can be easily developed. This allows for the integration of current and future heterogeneous wireless technologies to provide scalable and efficient mobile ubiquitous Internet access, able to adapt to different environments and user requirements. Following these goals, CARMEN aims to define, study and implement link and technology abstractions, mobility support, and quality of service. The architecture also includes advanced monitoring features that allow for dynamic self-configuration, thereby reducing the installation and operational costs.},
keywords={CARMEN, Specific Targeted Research Project, carrier grade services, metropolitan areas, wireless mesh networks },
}
</bibtex>
<bibtex>
@article{220,
author={A. Nafaa; S. Murphy; L. Murphy},
title={Analysis of a Large-Scale VOD Architecture for Broadband Operators: A P2P-Based Solution},
journal={IEEE Communications Magazine},
year={2008},
pages={47-55},
volume={46},
abstract={VOD services distribution is gaining unprecedented interest from the consumer communication industry due to its growing success in both the Internet and residential broadband market. In this article we present a scalable VOD distribution architecture for broadband operators. The solution is based on a P2P streaming concept in which a VOD streaming session requested by a given STB (Set-Top-Box) is actually provisioned via a multisource streaming session. This solution has the advantage of scaling naturally with the number of STBs in the network. In this article we focus on efficiently translating the popularity distribution into content availability in the network. Different aspects related to this issue are analyzed and challenges highlighted.
},
keywords={video on demand, peer-to-peer, popularity distribution, content availability},
}
</bibtex>
<bibtex>
@article{221,
author={Y. Qiao; E. Fallon; J. Murphy; L. Murphy; X. Zhu; G. Hayes; A. Matthews; A. Hanley},
title={Performance Analysis of Multi-homed Transport Protocols with Network Failure Tolerance},
journal={IET Communications},
year={2008},
pages={336-345},
volume={2},
abstract={This paper studies the performance of multi-homed transport protocols tolerant of network failure. It evaluates the performance of different retransmission policies combined with path failure detection thresholds, infinite or finite receive buffers for various path bandwidths, delays and loss rate conditions through SCTP simulation. The results show that retransmission policies perform differently with different path failure detection threshold configurations. It identifies that retransmission of all data on an alternate path with the path failure detection threshold set to zero performs best in symmetric path conditions but its performance degrades acutely in asymmetric path conditions even when the alternate path delay is shorter than the primary path delay. It illustrates that retransmission of all data on the same path with the path failure detection threshold set to one or zero gives the most stable performance in all path configurations.
},
keywords={Fault-tolerant computing, transport protocols},
pdf={performance analysis.pdf},
}
</bibtex>
<bibtex>
@article{222,
author={A. Nafaa; T. Taleb; L. Murphy},
title={Forward Error Correction Strategies for Media Streaming over Wireless Networks},
journal={IEEE Communications Magazine},
year={2008},
pages={72-79},
volume={46},
abstract={The success of next-generation mobile communication systems depends on the ability of service providers to engineer new added-value multimedia-rich services, which impose stringent constraints on the underlying delivery/transport architecture. The reliability of real-time services is essential for the viability of any such service offering. The sporadic packet loss typical of wireless channels can be addressed using appropriate techniques such as the widely-used packet-level Forward Error Correction. In designing channel-aware media streaming applications, two interrelated and challenging issues should be tackled: accuracy of characterizing channel fluctuations and effectiveness of application-level adaptation. The first challenge requires thorough insight into channel fluctuations and their manifestations at the application level, while the second concerns the way those fluctuations are interpreted and dealt with by adaptive mechanisms such as FEC. In this article we review the major issues that arise when designing a reliable media streaming system for wireless networks.
},
keywords={Forward error correction, multimedia streaming, wireless channel conditions},
}
</bibtex>
<bibtex>
@article{334,
author={Trofin,M.;Murphy,J.},
title={Static Verification of Component Composition in Contextual Composition Frameworks},
journal={International Journal on Software Tools for Technology Transfers},
year={2008},
pages={247-261(15 pages)},
volume={10(3)},
abstract={Contextual component frameworks, such as Enterprise JavaBeans (EJB), allow for components to specify boundary conditions for the runtime context. These conditions are satisfied at runtime by services of the underlying platform, thus ensuring that the context in which components run exhibits properties that allow them to operate correctly. Depending on how components call each other, it is possible that satisfying such conditions lead to problems such as reduced performance due to redundant service execution, or permanent errors (composition mismatches), due to incompatible boundary conditions. Currently, the semantics of these boundary conditions are expressed in natural language only, making it impossible to incorporate them into an automatic analysis tool. Furthermore, early understanding of how components call each other would be necessary, but it is currently difficult to achieve by means of a tool, as the method dispatch rules in a component system differ from the dispatch rules of the programming language(s) in which they were developed. We have developed a metamodel, $${\mathbb{M}}$$ , for describing boundary conditions, an analysis method, $${\mathbb{A}}$$ , and a static component-level call graph extraction method for EJB applications, CHA EJB . $${\mathbb{A}}$$ uses $${\mathbb{M}}$$ models to analyze inter-component call graphs, and thus detect problems such as composition mismatches or redundancies, thus allowing for remedial action to take place. We present $${\mathbb{M}},{\mathbb{A}}$$ and CHA EJB in this article, show that $${\mathbb{A}}$$ produces correct results, and describe a prototype analysis tool implementing the three, which we used to validate our approach on two popular EJB applications. },
keywords={Software components - Contextual composition - Static analysis - Enterprise Java },
pdf={static verification.pdf},
}
</bibtex>
<bibtex>
@article{336,
author={Parsons,T.;Murphy,J.},
title={Detecting Performance Antipatterns in Component Based Enterprise Systems},
journal={Journal of Optical Technology},
year={2008},
pages={55-90(36 pages)},
volume={7(3)},
abstract={We introduce an approach for automatic detection of performance antipatterns. The approach is based on a number of advanced monitoring and analysis techniques. The advanced analysis is used to identify relationships and patterns in the monitored data. This information is subsequently used to reconstruct a design model of the underlying system, which is loaded into a rule engine in order to identify predefined antipatterns. We give results of applying this approach to identify a number of antipatterns in two JEE applications. Finally, this work also categorises JEE antipatterns into categories based on the data needed to detect them.},
keywords={Component Systems,Antipatterns},
pdf={detecting performance.pdf},
}
</bibtex>
<bibtex>
@article{405,
author={O.Ashagi;S.Murphy;L.Murphy},
title={Interference Mitigation in License-exempt 802.16 systems:a distributed approach},
journal={Unlicensed Mobile Access Technology},
year={2008},
pages={49-50},
volume={August },
abstract={Operating in license-exempt IEEE 802.16 wireless spectrum is a challenging research issue. The
research focus is on deriving intelligent algorithms to mitigate the interference that occurs between
different users. In this chapter, we propose an enhancement to our previously published distributed
approach to mitigate interference between 802.16 systems operating in close proximity, by introducing
a re-listening mechanism to determine whether there are more subcarriers available in the
channel than what the base stations (BSs) are currently using.
Simulation results show that the re-listening mechanism offers a 100 percent throughput
increase for some BSs. Our results also show the general trend of throughput variations between
the downlink and the uplink, due to the differences in transmission power.},
keywords={IEEE 802.16,},
pdf={interference.pdf},
}
</bibtex>
<bibtex>
@article{425,
author={C.H.Muntean},
title={Improving Learner Quality of Experience by Content Adaptation based on Network Conditions},
journal={Computers in Human Behaviour},
year={2008},
pages={1452-1472},
volume={24},
abstract={Apart from user characteristics, properties of the network over which the content is delivered and
device on which the content is displayed affect end-user perceived quality. This paper presents a learner
quality of experience (QoE) model that apart from the user-related content adaptation, considers
delivery performance-based content personalisation in order to improve user experience when interacting
with an online learning system.
A comparison-based study on the benefit of using the proposed learner QoE model in adaptive
and personalized education was conducted involving the original AHA! and QoEAHA – a version
of AHA! enhanced with the learner QoE model. Testing results demonstrate significant benefits in
terms of learning achievement, learning performance, learner navigation and user QoE in favour
of the learner QoE model-enhanced solution.},
keywords={QoE},
pdf={Muntean_2008_Computers-in-Human-Behavior.pdf},
}
</bibtex>
<bibtex>
@article{453,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={Open Corpus Architecture for Personalised Ubiquitous e-Learning},
journal={Personal & Ubiquitous Computing},
year={2008},
pages={197-205},
volume={13},
abstract={As the e-learning area matures, there are a
growing number of e-learning content providers that
produce and distribute material that covers a large range of
topics, differs in quality and is represented in various formats.
Lately, different devices and various network
technologies allow extensive user access to educational
content almost anywhere, anytime and from any device.
Ubiquitous e-learning has the potential to provide continuous
and context-based, educational material to human
learners anytime, anywhere and on any device. Since each
person has different expectations related to the content, the
performance of the delivery and display of that content, it
is desirable for an ubiquitous e-learning environment to
provide user-oriented personalisation of e-learning material.
However very often there are multiple sources of
e-learning material at various web locations (open corpus
resources) that cover the same topic, but differ in terms of
quality, formatting and even cost. It is very difficult for
learners to select the content that best suits their interests
and goals, characteristics of the device used and delivery
network as well as their cost budget. This paper proposes
an innovative ubiquitous e-learning environment called
Performance-based E-learning Adaptive Cost-efficient
Open Corpus frameworK (PEACOCK) that provides
support for the selection and distribution of personalised
e-learning rich media content (e.g. multimedia, pictures,
graphics and text) to e-learners such as it will best suit
users’ interests and goals, meet their formatting preferences
and cost constraints, while considering the limitations
introduced by the end-user devices and the delivery networks
to the user. PEACOCK’s main goal is to maximise
the users’ e-learning experience and increase their learning
satisfaction and learning outcome.},
keywords={Adaptive e-learning systems �},
pdf={open corpus.pdf},
}
</bibtex>
<bibtex>
@article{454,
author={Gabriel-Miro Muntean;G.Ghinea;T.N.Sheehan},
title={Region of Interest-based Adaptive Multimedia Streaming Scheme},
journal={IEEE Trans. on Broadcasting},
year={2008},
pages={296-303},
volume={54},
abstract={Adaptive multimedia streaming aims at adjusting
the transmitted content based on the available bandwidth such as
losses that often severely affect the end-user perceived quality are
minimized and consequently the transmission quality increases.
Current solutions affect equally the whole viewing area of the
multimedia frames, despite research showing that there are regions
on which the viewers are more interested in than on others.
This paper presents a novel region of interest-based adaptive
scheme (ROIAS) for multimedia streaming that when performing
transmission-related quality adjustments, selectively affects the
quality of those regions of the image the viewers are the least
interested in. As the quality of the regions the viewers are the
most interested in will not change (or will involve little change),
the proposed scheme provides higher overall end-user perceived
quality than any of the existing adaptive solutions.},
keywords={Content adaptation, multimedia streaming,},
pdf={region.pdf},
}
</bibtex>
<bibtex>
@article{455,
author={Gabriel-Miro Muntean;G.Ghinea;P.Frossard;M.Etoh;F.Speranza;H.R.Wu},
title={Advanced Solutions for Quality-Oriented Multimedia Broadcasting},
journal={IEEE Trans. on Broadcasting},
year={2008},
pages={494-498},
volume={54},
abstract={Multimedia content is increasingly being delivered
via different types of networks to viewers in a variety
of locations and contexts using a variety of devices. The ubiquitous
nature of multimedia services comes at a cost, however.
The successful delivery of multimedia services will require
overcoming numerous technological challenges many of which
have a direct effect on the quality of the multimedia experience.
For example, due to dynamically changing requirements and
networking conditions, the delivery of multimedia content
has traditionally adopted a best effort approach. However,
this approach has often led to the end-user perceived quality
of multimedia-based services being negatively affected. Yet
the quality of multimedia content is a vital issue for the
continued acceptance and proliferation of these services. Indeed,
end-users are becoming increasingly quality-aware in
their expectations of multimedia experience and demand an
ever-widening spectrum of rich multimedia-based services.},
keywords={Multimedia,Network},
pdf={advanced solution.pdf},
}
</bibtex>
<bibtex>
@article{399,
author={T.Taleb;A.Nafaa;L.Murphy;K.Hashimoto;N.Kato;Y.Nemoto},
title={Towards Efficient Service-Level QoS Provisioning in Large Scale 802.11-Based Networks},
journal={IEEE Network:Special Issue on Advances in Broadband Access Networks},
year={2007},
pages={42-48},
volume={21},
abstract={Along with recent advances in mobile networking and portable computing technologies,
there is a trend in the telecommunications industry toward the development
of efficient ubiquitous systems that can provide a set of bandwidth-intensive
and real-time services to multiple users while supporting their full mobility. Largescale
deployment of 802.11-based technologies will play an integral part in the
construction of such ubiquitous wireless mobile systems. A challenging task in the
development of such networks is efficient provisioning of QoS-enabled services for
mobile users. In this context, we propose a scheme that constantly monitors the
overall network performance to perform admission control and traffic conditioning
at the 802.11-based access points and mobile terminals. The focus is on servicelevel
fairness, where different flows from the same traffic class can still receive the
same QoS level even if they have different bit rates. Furthermore, given the mobility
of users, the success of any resource allocation and admission control model
depends on the continuity of QoS guarantees across different WLANs. This article
proposes a dynamic service level agreement negotiation protocol that allows
mobile terminals to perform handoffs between different WLANs while maintaining
the agreed level of service. End users also can change their service levels in
response to changes in network conditions.},
keywords={Internet,802.11,Wireless Mobile,QoS},
pdf={toward efficient.pdf},
}
</bibtex>
<bibtex>
@article{403,
author={G.Muntean;P.Perry;L.Murphy},
title={A Comparison Based Study of Quality Oriented Video on Demand},
journal={IEEE Transactions on Broadcasting},
year={2007},
pages={92-102},
volume={53},
abstract={The Quality Oriented Adaptation Scheme (QOAS) is
used for high bit-rate multimedia streaming in local broadband
multi-service all-IP networks. It balances two opposing goals:
providing high quality multimedia-based services to end-users, and
increasing the infrastructure utilisation and number of customers
simultaneously served. Extensive objective testing results presented
in this paper show that QOAS achieves high performance in terms of
end-user perceived quality, loss rate, throughput, link utilisation, and
number of customers simultaneously served. These results were
obtained even in highly loaded and variable delivery conditions
caused by traffic of different types, sizes, and variation patterns.
QOAS performance was assessed stand-alone and in comparison
with other existing solutions, adaptive and non-adaptive.},
keywords={Adaptive video streaming, feedback control, grading scheme, end-user perceived quality.},
pdf={a comparison.pdf},
}
</bibtex>
<bibtex>
@article{409,
author={C.H.Muntean;G.M.Muntean;J.McManis;A.I.Cristea},
title={Quality of Experience-LAOS:Create Once,Use Many,Use Anywhere},
journal={International Journal of Learning Technology},
year={2007},
pages={209-229},
volume={3},
abstract={This paper proposes QoE-LAOS, a Quality of Experience-oriented adaptive authoring model that enables performance-aware adaptation. It extends the existing LAOS authoring model in order to consider display and delivery performance issues. QoE-LAOS involves the addition of three new QoE sublayers: QoE Content Features sublayer, QoE Characteristics sublayer and QoE Rules sublayer. These proposed QoE sublayers are deployed at LAOS's Domain, Adaptation and Presentation Models, respectively. This paper formalises and exemplifies QoE-LAOS and discusses authoring-related issues in relation to each new sublayer. },
keywords={adaptive hypermedia, adaptive educational hypermedia, AEH, adaptive author assistance, semi-automatic adding, authoring models, authoring tools, adaptive web application engineering, adaptive web application authoring, adaptive learning, adaptive systems,},
pdf={quality of experience.pdf},
}
</bibtex>
<bibtex>
@article{396,
author={N.Cranley;L.Murphy},
title={Incorporating User Perception in Adaptive Video Streaming Systems},
journal={Digital Multimedia Perception & Design},
year={2006},
pages={860-861},
volume={May 2006},
abstract={There is an increasing demand for streaming video applications over both the fixed
Internet and wireless IP networks. The fluctuating bandwidth and time-varying delays
of best-effort networks makes providing good quality streaming a challenge. Many
adaptive video delivery mechanisms have been proposed over recent years; however,
most do not explicitly consider user-perceived quality when making adaptations, nor
do they define what quality is. This chapter describes research that proposes that an
optimal adaptation trajectory through the set of possible encodings exists, and
indicates how to adapt transmission in response to changes in network conditions in
order to maximize user-perceived quality.},
keywords={Video Streaming,Internet,IP Networks},
pdf={incorporating.pdf},
}
</bibtex>
<bibtex>
@article{410,
author={C.H.Muntean;J.McManis},
title={End-User Quality of Experience Oriented Adaptive E-learning System},
journal={Journal of Digital Information},
year={2006},
pages={1},
volume={7},
abstract={In the context of new devices and with a variety of network technologies that allow access to the Internet, the providers of e-learning materials have to ensure that the users have a positive experience using their e-learning systems and they are happy to re-use them. Adaptive Hypermedia research aims to provide personalised educational material that ensures a positive learning experience for the end-users. However, user experience is dependent not only on the content served to them, but also on the user perceived performance of the e-learning system. This leads to a new dimension of individual differences between Web users: the end-user Quality of Experience (QoE). We have proposed a solution for Adaptive Hypermedia Systems (AHS) that provides satisfactory end-user QoE through the use of a new QoE layer. This layer attempts to take into account multiple factors affecting QoE in relation to the delivery of a wide range of Web components such as text, images, video, audio.

The effectiveness of our QoE layer has been tested in comparison to a standard educational AHS and the results of these tests are presented in this paper. Different educational-based evaluation techniques such as learner achievement analysis, learning performance assessment, usability survey and correlation analysis between individual student performance and judgment on system usability were applied in order to fully assess the performance of the proposed QoE layer. Results of the tests showed that the use of the QoE layer brought significant improvements in terms of user learning performance, system usability and user satisfaction with the personalised e-learning system while not affecting the user learning achievement
},
keywords={end-user QoE, adaptive hypermedia, e-learning, end-user perceived performance, learning performance },
pdf={end user quality.doc},
}
</bibtex>
<bibtex>
@article{419,
author={N.Cranley;P.Perry;L.Murphy},
title={User Perception of Adapting Video Quality},
journal={International Journal of Human-Computer Studies/Knowledge Acquisition},
year={2006},
pages={637-647},
volume={64},
abstract={In general, video quality adaptation and video quality evaluation are distinct activities. Most adaptive delivery mechanisms for
streaming multimedia content do not explicitly consider user-perceived quality when making adaptation decisions. Equally, video quality
evaluation techniques are not designed to evaluate instantaneous quality where the quality is changing over time. We propose that an
Optimal Adaptation Trajectory (OAT) through the set of possible encoding exists, and that it indicates how to adapt encoding quality in
response to changes in network conditions in order to maximize user-perceived quality. The subjective and objective tests carried out to
find such trajectories for a number of different MPEG-4 video clips are described. Experimental subjective testing results are presented
that demonstrate the dynamic nature of user perception with adapting multimedia. The results demonstrate that adaptation using the
OAT out-performs conventional adaptation strategies in which only a single aspect of the video quality is adapted. In contrast, the OAT
provides a mechanism to adapt multiple aspects of the video quality thereby giving better user-perceived quality in both the short and
long term.},
keywords={Video quality; Evaluation/methodology; Perception; Subjective and objective quality; Adaptation},
pdf={user perception.pdf},
}
</bibtex>
<bibtex>
@article{420,
author={N.Cranley;L.Murphy;P.Perry},
title={Dynamic Content-Based Adaptation of Streamed Multimedia,Intelligence-based Adaptation for Ubiquitous Multimedia Communications},
journal={Journal of Network & Computer Applications},
year={2006},
pages={983-1006},
volume={30},
abstract={Most adaptive delivery mechanisms for streaming multimedia content do not explicitly
consider user-perceived quality when making adaptation decisions. We show that an optimal
adaptation trajectory (OAT) through the set of possible encodings exists, and that it indicates
how to adapt encoding quality in response to changes in network conditions in order to
maximise user-perceived quality. The OAT is related to the characteristics of the content, in
terms of spatial and temporal complexity. We describe a method to automatically determine
the OAT in response to the time-varying characteristics of the content. In this way, as the
characteristics of the content change over time, the system can dynamically and intelligently
adjust the adaptation process in order to maximise the user-perceived quality. The OAT can
be used with any sender-based transmission adaptation policy. We demonstrate content-based
adaptation using the OAT in a practical system using two different adaptation algorithms.
Furthermore, we show how this form of adaptation can result in differing adaptation
behaviour not only as a result of the dynamics of the content but also as a result of the
adaptation algorithm being used. Finally, we show how increased feedback frequency does not
necessarily improve the behaviour of the adaptation algorithm being used.},
keywords={User perception; Video quality; Adaptive systems; Multimedia},
pdf={dynamic.pdf},
}
</bibtex>
<bibtex>
@article{300,
author={Brebner,P.; Cecchet,E.; Marguerite,J.; Tuma,P.; Ciuhandu,O.; Dufour,B.; Eeckhout,L.; Frenot,S.; Krishna,A.S.; Murphy,J.; Verbrugge,C.},
title={Middleware Benchmarking: Approaches, Results, Experiences,},
journal={Concurrency & Computation-Practice & Experience},
year={2005},
pages={1799-1805(7 pages)},
volume={17(15)},
abstract={The report summarizes the results of the Workshop on Middleware Benchmarking held during OOPSLA
2003. The goal of the workshop was to help advance the current practice of gathering performance
characteristics of middleware implementations through benchmarking. The participants of the workshop
have focused on identifying requirements of and obstacles to middleware benchmarking and forming
a position on the related issues. Selected requirements and obstacles are presented, together with
guidelines to adhere to when benchmarking, open issues of current practice, and perspectives on further
research},
keywords={middleware benchmarking; middleware performance; middleware scalability; middleware evaluation; middleware benchmark design; benchmarking guidelines; benchmarking measurement; benchmarking metrics; OOPSLA 2003 workshop},
pdf={middleware benchmarking.pdf},
}
</bibtex>
<bibtex>
@article{308,
author={Klusek,B.;Murphy,J.;Barry,L.P.},
title={New Fiber Delay Line Usage Strategy in Optical Burst Switching Networks},
journal={Networks & Communication Systems},
year={2005},
pages={5 Pages},
volume={NCS 2005},
abstract={Optical Burst Switching (OBS) is a new paradigm for
future all-optical networks. In an OBS node, a Fiber
Delay Line may be used to delay a burst, effectively
increasing its offset time. Traditionally, FDLs were used
in contention resolution, i.e. a burst was only buffered if
it would otherwise been dropped. We propose a different
approach, where delay lines are used also to better arrange
bursts in time. In our strategy both outgoing channels
and FDL channels are assigned a price, according to their
suitability for a particular burst. When a control packet
arrives at a core node, all the possible ways of handling the
corresponding burst are found (the outgoing channel, with
or without a FDL), and the one with a lowest total price is
chosen. This makes it possible to use most FDL channels
for the majority of the time, reducing the probability of
future contention. We present simulation results, showing
how node performance depends on the size of a FDL bank,
using either Last Available Unused Channel with Void
Filling (LAUC-VF) and the traditional FDL usage strategy
or our algorithm.},
keywords={High-speed Internet, Optical Burst Switching, Fiber Delay Lines, burst scheduling},
pdf={new fiber.pdf},
}
</bibtex>
<bibtex>
@article{380,
author={G.Muntean;P.Perry;L.Murphy},
title={Subjective Assessment of the Quality-Oriented Adaptive Scheme},
journal={IEEE Transactions on Broadcasting},
year={2005},
pages={276-286},
volume={51},
abstract={The Quality-Oriented Adaptation Scheme (QOAS)
supports the distribution of high quality multimedia services
to a large number of simultaneous customers via given broadband
IP infrastructure. This paper presents subjective testing
results that augment previously reported objective performance
assessment. Clips representing different classes of multimedia
sequences in terms of motion content and types were selected
and streamed using a QOAS-based prototype system. Congested
delivery network conditions were emulated and the effects of the
consequent QOAS-driven adaptations were subjectively assessed
by end-users. The test subjects have also graded their perceived
quality when using a nonadaptive streaming approach. The
QOAS-related results were much higher than those obtained for
a nonadaptive approach, being above the “good” perceptual level
for all multimedia clips and in all tested delivery conditions.},
keywords={Adaptive multimedia streaming, end-user perceived quality, feedback control, subjective testing.},
pdf={subjective.pdf},
}
</bibtex>
<bibtex>
@article{382,
author={N.Cranley;P.Perry;L.Murphy},
title={Optium Adaptation Trajectories for Streamed Multimedia},
journal={ACM Multimedia Systems },
year={2005},
pages={392-401},
volume={10},
abstract={Most adaptive delivery mechanisms for streaming
multimedia content do not explicitly consider user-perceived
quality when making adaptations. We propose that an optimal
adaptation trajectory through the set of possible
encodings exists and that it indicates how to adapt encoding
quality in response to changes in network conditions to
maximize user-perceived quality. Such an optimum adaptation
trajectory can be used with any transmission adaptation
policy. We describe the subjective tests we carried out to
find such trajectories for a number of different MPEG-4
video clips and indicate how this knowledge could be used
in the operation of a practical system.},
keywords={Perceptual video quality · Adaptive multimedia transmission · Subjective testing · Video encoding},
pdf={optium adaptation.pdf},
}
</bibtex>
<bibtex>
@article{383,
author={M.Narbutt;A.Kelly;L.Murphy;P.Perry},
title={Adaptive VoIP playout Scheduling :A new method for assesing user satisfaction},
journal={IEEE Internet Computing},
year={2005},
pages={28-34},
volume={July 2005},
abstract={Delay and packet loss dramatically affect the quality of a voice-over-IP (VoIP) call
and depend on the playout buffer scheme implemented at the receiver. The
choice of playout algorithm can’t be based on statistical metrics without
considering the perceived end-to-end conversational speech quality. The authors
present a method for evaluating various playout algorithms that extends the Emodel
concept by estimating user satisfaction from time-varying transmission
impairments. This article evaluates several playout algorithms and shows a
correspondence between their results and those obtained via statistical loss and
delay metrics.},
keywords={Delay,Jitter,Packet Loss},
pdf={adaptive voip.pdf},
}
</bibtex>
<bibtex>
@article{285,
author={Dantcha,A.;Barry,L.;Murphy J.;Dunne,J.;Mullane,T.;Mcdonald,D.},
title={BER Performance in Wavelength Packet Switched WDM systems during Nano-Second Wavelength switching Events},
journal={Journal of Optical Communication},
year={2004},
pages={171-177(7Pages)},
volume={242},
abstract={An important characteristic of wavelength tuneable laser transmitters is that as
they tune between output wavelength channels they may generate light at a range of other
wavelengths. This effect may ultimately influence the design of WDM wavelength packetswitched
networks employing wavelength tuneable transmitters. We have investigated this
effect by examining the BER transmission performance of a WDM channel as a function
of the degree of attenuation of another WDM wavelength signal during fast wavelength
switching events. Our results show the importance of attenuating the output signal from
the wavelength switched laser in order to prevent performance degradations on the
monitored data channel.},
keywords={Optical communications, networks, wavelength division multiplexing, tuneable laser, packet switching, cross-channel interference},
pdf={ber performance.pdf},
}
</bibtex>
<bibtex>
@article{372,
author={G.Muntean;P.Perry;L.Murphy},
title={Performance Comparison of Local Area Video Streaming Systems},
journal={IEEE Communications Letters},
year={2004},
pages={326-328},
volume={8},
abstract={The performance of our Quality Oriented
Adaptation Scheme (QOAS) for multimedia streaming in local
networks is compared with other existing solutions (TFRCP,
LDA+, and non-adaptive). This comparison is done in terms of
bandwidth utilization, number of concurrent clients, loss rate,
and end-user perceived quality. Simulation results show that for
the same average end-user quality, our QOAS system can
accommodate a significantly higher number of simultaneous
clients while also having higher bandwidth utilization. For the
same number of clients, the average end-user quality is always
higher for QOAS than for the other solutions studied.},
keywords={Adaptive video streaming, feedback control, grading scheme, end-user quality.},
pdf={performance comparison.pdf},
}
</bibtex>
<bibtex>
@article{375,
author={G.Muntean;P.Perry;L.Murphy},
title={A New Adaptive Multimedia Streaming System for ALL-IP Multi Service Networks},
journal={IEEE Transactions on Broadcasting},
year={2004},
pages={1-10},
volume={50},
abstract={A significant challenge in all-IP multi-service networks
is to balance the goal of providing high-quality services to
the end-users with the desire to maximize the number of end-users
that can be simultaneously served. This paper presents a solution
to this challenge by using the Quality-Oriented Adaptation
Scheme (QOAS) for delivering multimedia streams. This adaptive
mechanism uses feedback from clients regarding the quality of
delivery to assist the server in making dynamic adjustments to
the transmitted streams. Experimental objective and subjective
test results illustrate the significant performance improvements
achieved by QOAS, both in terms of number of simultaneous
viewers served and of end-user perceived quality.},
keywords={Adaptive multimedia streaming, all-IP multi-service networks, dynamic feedback, grading scheme, statistical multiplexing.},
pdf={new adaptive.pdf},
}
</bibtex>
<bibtex>
@article{357,
author={G.Muntean;P.Perry;L.Murphy},
title={Quality Oriented Adaptation Scheme for Video-On-Demand},
journal={IEE Electronic Letters},
year={2003},
pages={1689-1690},
volume={39},
abstract={The QOAS system proposed in [1, 2] is used for MPEG2 Video-on-Demand (VoD) delivery in local
multi-service IP networks. QOAS balances the need for high end-user quality with increased network utilisation,
regardless of the nature of other cross traffic. A high utilisation would allow an increased number of customers to be
served from a limited infrastructure, minimising the costs, but decreasing the end-user quality. The goal of QOAS is
to maximise end-user perceived quality and links’ utilisation in the existing network conditions.
QOAS varies the transmitted quantity of video data by dynamically adjusting the quality of the streamed video. In
comparison with other approaches [3], its novelty is that these adjustments are carried out based on client-computed
quality scores that describe the current quality of delivery sent via regular feedback. These scores include shortterm
and long-term assessments of both the end-user perceived video quality [1] and IP performance
parameters (e.g. delay, jitter, loss rate). During transmission the video quality is varied in a controlled manner
according to the feedback reports. It requires fewer negative quality scores to trigger a quality decrease than positive
for an increase. This ensures a fast reaction during bad delivery conditions helping to eliminate their cause and
makes sure that quality upgrades are performed only after the network conditions have improved.},
keywords={MPEG,QoS,IP Networks},
pdf={quality oriented.pdf},
}
</bibtex>
<bibtex>
@article{415,
author={H.Melvin;L.Murphy},
title={Time Synchronization for VoIP Quality of Service},
journal={IEEE Internet Computing},
year={2002},
pages={6 Pages},
volume={25-26},
abstract={Although packet-based and unmanaged
networks like the Internet
are ideal for delivering timeinsensitive
data such as e-mail or static
Web traffic, the growing demand for
Web-based multimedia data exposes the
limitations of core Internet protocols.
With no end-to-end delay bounds, the
public Internet’s best-effort service is
unsuitable for delivering time-sensitive
data and for interactive applications such
as voice-over-IP.
Normal speech consists of talkspurts,
which typically last a few hundred milliseconds,
and silence periods, which
occur both within a spoken word and
between words. In a packet-based network,
voice packets are generated periodically
at the sender and transmitted across
the network. To cope with the packet
interarrival variance inherent in besteffort
service, current VoIP implementations
generally implement fixed buffer
schemes. Fixed buffer schemes make no
attempt to match receiver operation to
current network performance. An alternative
approach is to use a more complex
adaptive buffer scheme. This continuously
matches playout delay to network conditions,
at the expense of some packet
loss due to late arrivals and some distortion
of intertalkspurt silence periods.
Various approaches seek to optimize
the quality of service of VoIP applications
(see the sidebar, “Quality of Service for
VoIP,” next page, for a categorization of
QoS approaches). We propose a system
that uses synchronized time to combine
the useful characteristics of both fixed
and adaptive buffer strategies, thereby
improving VoIP quality of service. Using
a combination of global positioning system
(GPS) technologies and the network
time protocol (NTP), hosts can learn the
precise end-to-end delay for each packet.
This information can benefit both domestic
and business Internet telephony users.
In this article, we outline our proposed
system and discuss issues arising from the
use of synchronized time.},
keywords={Web Traffic,Web-based Multimedia,VoIP},
pdf={time.pdf},
}
</bibtex>

Pubs:journal

2012-03-09T13:10:27Z

Root:

<bibtex>
@article{484,
author={Frank A. Zdarksy, Sebastian Robitzsch, Albert Banchs},
title={Security Analysis of Wireless Mesh Backhauls for Mobile Networks},
journal={Journal of Network and Computer Applications},
year={2010},
pages={--},
volume={In Press},
abstract={Radio links are used to provide backhaul connectivity for base stations of mobile networks, in cases in which cable-based alternatives are not available and cannot be deployed in an economic or timely manner. While such wireless backhauls have been predominantly used in redundant tree and ring topologies in the past, mobile network operators have become increasingly interested in meshed topologies for carrier-grade wireless backhauls. However, wireless mesh backhauls are potentially more susceptible to security vulnerabilities, given that radio links are more exposed to tampering and given their higher system complexity.

This article extends prior security threat analyses of 3rd generation mobile network architectures for the case of wireless mesh backhauls. It presents a description of the security model for the considered architecture and provides a list of the basic assumptions, security objectives, assets to be protected and actors of the analysis. On this foundation, potential security threats are analyzed and discussed and then assessed for their corresponding risk. The result of this risk assessment is then used to define a set of security requirements. Finally, we give some recommendations for wireless mesh backhaul designs and implementations following these requirements.},
keywords={Security analysis, Wireless mesh backhauls, Mobile networks},
pdf={2010 - Zdarsky, Robitzsch, Banchs.pdf},
}
</bibtex>
<bibtex>
@article{244,
author={Seung-Bum Lee;Gabriel-Miro Muntean;Alan F. Smeaton},
title={Performance-aware Replication of Distributed Pre-recorded IPTV Content},
journal={IEEE Transactions on Broadcasting Special Issue},
year={2009},
pages={-},
volume={(in press)},
abstract={Video recording in IPTV systems is a promising service that provides time-shifted services in relation to storing TV content closer to user devices such as set-top boxes. Existing approaches do not support collaboration between nodes which have correlated contents, a fact that can affect the performance of the overall system. To make this service more interactive and proactive, this paper presents the architecture using the Smart Personal Information Network (Smart PIN) as a novel performance-based content sharing network for IPTV content which uses a user-centric utility-based Multimedia Data Replication Scheme (MDRS). This allows the exchange of data based on both network performance and user interest in exchanged multimedia content in order to achieve ef?cient content sharing. The proposed solution is evaluated through extensive simulations and results show much improved behaviour in comparison with two other existing general purpose data replicat on schemes.},
keywords={IPTV, Data replication, Content management, Peer-to-peer},
}
</bibtex>
<bibtex>
@article{253,
author={Bogdan Ciubotaru; Gabriel-Miro Muntean},
title={SASHA - A Quality-Oriented Handover Algorithm for Multimedia Content Delivery to Mobile Users},
journal={IEEE Transactions on Broadcasting Special Issue},
year={2009},
pages={-},
volume={(in press)},
abstract={The convergence of the existing network access technologies to a common IP-based architecture and the increase in popularity of accessing video content over the Internet makes IPTV a promising solution for media and entertainment industries. Additionally, video content delivery to the increasingly popular mobile devices over heterogeneous wireless networks makes IPTV even more appealing. However the distribution of multimedia content over heterogeneous wireless networks to mobile devices involves significant technical challenges related to mobility management and quality of service provisioning. The existing solutions do not consider quality of service as a decision making parameter for mobility management in general and handover management in particular.
This paper proposes the Smooth Adaptive Soft Handover Algorithm (SASHA), a novel quality-aware approach to handover based on load balancing among different networks using a comprehensive, Quality of Multimedia Streaming (QMS), function for decision making. SASHA represents the handover management solution at the core of the more comprehensive Multimedia Mobility Management System (M3S), a quality oriented mobility management framework for multimedia applications which maximizes user perceived quality by efficiently exploiting all available communication resources.
Simulation-based testing results are presented, outlining the performance of SASHA in different mobility scenarios. The evaluation is performed for different number of nodes performing handover simultaneous and for various situations in terms of networks’ overlapping area. The results shown indicate how SASHA outperforms other three mobility management solutions in terms of quality, scalability and resilience to the dynamics of the networks’ overlapping area.
},
keywords={Multimedia streaming, IPTV, Heterogeneous networks, Mobility, Handover},
pdf={Ciubotaru_Muntean_IPTV.pdf},
}
</bibtex>
<bibtex>
@article{338,
author={Fitzpatrick,J.;Murphy,S.;Atiauzzaman,M.;Murphy,J.},
title={Using Cross-Layer Metrics to Improve the Performance of End-to-End Handover Mechanisms},
journal={Computer Communication Preprint Online},
year={2009},
pages={13 Pages},
volume={10.1016},
abstract={Network centric handover solutions for all IP wireless networks usually require modifications to network
infrastructure which can stifle any potential rollout. This has led researchers to begin looking at alterna-
tive approaches. Endpoint centric handover solutions do not require network infrastructure modification,
thereby alleviating a large barrier to deployment. Current endpoint centric solutions capable of meeting
the delay requirements of Voice over Internet Protocol (VoIP) fail to consider the Quality of Service (QoS) that will be achieved after handoff. The main contribution of this paper is to demonstrate that QoS aware
handover mechanisms which do not require network support are possible. This work proposes a Stream
Control Transmission Protocol (SCTP) based handover solution for VoIP called Endpoint Centric Handover
(ECHO). ECHO incorporates cross-layer metrics and the ITU-T E-Model for voice quality assessment to
accurately estimate the QoS of candidate handover networks, thus facilitating a more intelligent handoff
decision. An experimental testbed was developed to analyse the performance of the ECHO scheme.
Results are presented showing both the accuracy of ECHO at estimating the QoS and that the addition
of the QoS capabilities significantly improves the handover decisions that are made.},
keywords={Echo,SCTP,VoIP,E-Model,Sigma},
pdf={using cross.pdf},
}
</bibtex>
<bibtex>
@article{339,
author={Qiao,Y.;Fallon,E.;Murphy,L.;Murphy,J.;Hanley,A.;Shi,Z.},
title={Transmission Scheduling for Multihomed Transport Protocols with Network Failure Tolerance},
journal={Telecommunication Systems Journal},
year={2009},
pages={10 pages},
volume={40},
abstract={In heterogeneous network environments, the
network connections of a multi-homed device may
have significant bandwidth differential. For a multihomed
transmission protocol designed for network
failure tolerance, such as SCTP, path selection
algorithms for data transmission drastically affect
performance. This article studies the effect of path
bandwidth differential on the performance of
retransmission strategies in multi-homing
environments. It identifies that fast retransmission on
an alternate path may cause receive buffer blocking
when path bandwidth differential is significant and the
receive buffer is limited. A theoretical model is
proposed for selecting retransmission path during the
fast retransmission phase, based on receive buffer and
path conditions. From these observations and analysis
results, this article proposes that path selection
strategies for transmitting new data and retransmitted
data should be decoupled. A new path selection
scheme is proposed and evaluated through SCTP
simulations.},
keywords={Multi-homing, Transmission Protocol, SCTP},
pdf={transmission.pdf},
}
</bibtex>
<bibtex>
@article{408,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={Open Corpus Architecture for Personalised Ubiquitous e-Learning},
journal={Personal & Ubiquitous Computing },
year={2009},
pages={197-205},
volume={13},
abstract={As the e-learning area matures, there are a growing number of e-learning content providers that produce and distribute material that covers a large range of topics, differs in quality and is represented in various formats. Lately, different devices and various network technologies allow extensive user access to educational content almost anywhere, anytime and from any device. Ubiquitous e-learning has the potential to provide continuous and context-based, educational material to human learners anytime, anywhere and on any device. Since each person has different expectations related to the content, the performance of the delivery and display of that content, it is desirable for an ubiquitous e-learning environment to provide user-oriented personalisation of e-learning material. However very often there are multiple sources of e-learning material at various web locations (open corpus resources) that cover the same topic, but differ in terms of quality, formatting and even cost. It is very difficult for learners to select the content that best suits their interests and goals, characteristics of the device used and delivery network as well as their cost budget. This paper proposes an innovative ubiquitous e-learning environment called Performance-based E-learning Adaptive Cost-efficient Open Corpus frameworK (PEACOCK) that provides support for the selection and distribution of personalised e-learning rich media content (e.g. multimedia, pictures, graphics and text) to e-learners such as it will best suit users’ interests and goals, meet their formatting preferences and cost constraints, while considering the limitations introduced by the end-user devices and the delivery networks to the user. PEACOCK’s main goal is to maximise the users’ e-learning experience and increase their learning satisfaction and learning outcome.
},
keywords={Adaptive e-learning systems - User-oriented personalisation - Cost-efficiency - Ubiquitous e-learning environment },
pdf={open corpus.pdf},
}
</bibtex>
<bibtex>
@article{456,
author={C.Xu;Gabriel-Miro Muntean;E.Fallon;A.Hanley},
title={Distributed Storage-Assisted Data-Driven Overlay Network for P2P VoD Services},
journal={IEEE Trans. on Broadcasting},
year={2009},
pages={1-10},
volume={55},
abstract={Providing VCR-like operations in Peer-to-Peer (P2P)
environments is a significant challenge. This paper proposes a distributed
Storage-assisted Data-driven overlay Network (SDNet)
to support P2P Video-on-Demand (VoD) services. It integrates
two networks: a Data-driven Overlay Network (DONet) and a
multi-way tree. DONet is enhanced and used for the routine video
distribution based on the buffer overlapping mechanism and
gossip protocol. A novel algorithm which uses a multi-way tree
structure and extra pre-fetching buffers at the nodes is proposed
to support efficient VoD operations. Videos are divided into uniform
segments, pre-fetched and stored in a distributed manner
along the tree topology. The cooperation between DONet-based
video delivery and the tree-located multimedia components enable
multimedia streaming interactive commands to be performed
efficiently. This paper presents and discusses the structure of
SDNet and the distributed storage scheme and details the cooperation
procedure. Simulation-based testing results show how the
proposed SDNet is an efficient interactive streaming solution in a
P2P environment.},
keywords={DONet, multi-way tree, P2P VoD, VCR-like.},
pdf={distributed.pdf},
}
</bibtex>
<bibtex>
@article{475,
author={Arturo Azcorra; Thomas Banniza; David Chieng; John Fitzpatrick; Dirk von-Hugo; Marek Natkaniec; Sebastian Robitzsch; Frank Zdarsky},
title={Supporting carrier grade services over wireless mesh networks: The approach of the European FP-7 STREP CARMEN [Very Large Projects]},
journal={IEEE Communications Magazine},
year={2009},
pages={14-16},
volume={47},
abstract={CARMEN is a three-year Specific Targeted Research Project (STREP) funded by the European Commission within the 7th Framework Program. The CARMEN access network will complement existing access technologies by exploiting low cost mesh networking techniques, thus minimizing deployment and maintenance costs. The CARMEN architecture introduces an abstraction layer that hides the specifics of the underlying access technology providing an abstract interface on top of which higher layers can be easily developed. This allows for the integration of current and future heterogeneous wireless technologies to provide scalable and efficient mobile ubiquitous Internet access, able to adapt to different environments and user requirements. Following these goals, CARMEN aims to define, study and implement link and technology abstractions, mobility support, and quality of service. The architecture also includes advanced monitoring features that allow for dynamic self-configuration, thereby reducing the installation and operational costs.},
keywords={CARMEN, Specific Targeted Research Project, carrier grade services, metropolitan areas, wireless mesh networks },
}
</bibtex>
<bibtex>
@article{220,
author={A. Nafaa; S. Murphy; L. Murphy},
title={Analysis of a Large-Scale VOD Architecture for Broadband Operators: A P2P-Based Solution},
journal={IEEE Communications Magazine},
year={2008},
pages={47-55},
volume={46},
abstract={VOD services distribution is gaining unprecedented interest from the consumer communication industry due to its growing success in both the Internet and residential broadband market. In this article we present a scalable VOD distribution architecture for broadband operators. The solution is based on a P2P streaming concept in which a VOD streaming session requested by a given STB (Set-Top-Box) is actually provisioned via a multisource streaming session. This solution has the advantage of scaling naturally with the number of STBs in the network. In this article we focus on efficiently translating the popularity distribution into content availability in the network. Different aspects related to this issue are analyzed and challenges highlighted.
},
keywords={video on demand, peer-to-peer, popularity distribution, content availability},
}
</bibtex>
<bibtex>
@article{221,
author={Y. Qiao; E. Fallon; J. Murphy; L. Murphy; X. Zhu; G. Hayes; A. Matthews; A. Hanley},
title={Performance Analysis of Multi-homed Transport Protocols with Network Failure Tolerance},
journal={IET Communications},
year={2008},
pages={336-345},
volume={2},
abstract={This paper studies the performance of multi-homed transport protocols tolerant of network failure. It evaluates the performance of different retransmission policies combined with path failure detection thresholds, infinite or finite receive buffers for various path bandwidths, delays and loss rate conditions through SCTP simulation. The results show that retransmission policies perform differently with different path failure detection threshold configurations. It identifies that retransmission of all data on an alternate path with the path failure detection threshold set to zero performs best in symmetric path conditions but its performance degrades acutely in asymmetric path conditions even when the alternate path delay is shorter than the primary path delay. It illustrates that retransmission of all data on the same path with the path failure detection threshold set to one or zero gives the most stable performance in all path configurations.
},
keywords={Fault-tolerant computing, transport protocols},
pdf={performance analysis.pdf},
}
</bibtex>
<bibtex>
@article{222,
author={A. Nafaa; T. Taleb; L. Murphy},
title={Forward Error Correction Strategies for Media Streaming over Wireless Networks},
journal={IEEE Communications Magazine},
year={2008},
pages={72-79},
volume={46},
abstract={The success of next-generation mobile communication systems depends on the ability of service providers to engineer new added-value multimedia-rich services, which impose stringent constraints on the underlying delivery/transport architecture. The reliability of real-time services is essential for the viability of any such service offering. The sporadic packet loss typical of wireless channels can be addressed using appropriate techniques such as the widely-used packet-level Forward Error Correction. In designing channel-aware media streaming applications, two interrelated and challenging issues should be tackled: accuracy of characterizing channel fluctuations and effectiveness of application-level adaptation. The first challenge requires thorough insight into channel fluctuations and their manifestations at the application level, while the second concerns the way those fluctuations are interpreted and dealt with by adaptive mechanisms such as FEC. In this article we review the major issues that arise when designing a reliable media streaming system for wireless networks.
},
keywords={Forward error correction, multimedia streaming, wireless channel conditions},
}
</bibtex>
<bibtex>
@article{334,
author={Trofin,M.;Murphy,J.},
title={Static Verification of Component Composition in Contextual Composition Frameworks},
journal={International Journal on Software Tools for Technology Transfers},
year={2008},
pages={247-261(15 pages)},
volume={10(3)},
abstract={Contextual component frameworks, such as Enterprise JavaBeans (EJB), allow for components to specify boundary conditions for the runtime context. These conditions are satisfied at runtime by services of the underlying platform, thus ensuring that the context in which components run exhibits properties that allow them to operate correctly. Depending on how components call each other, it is possible that satisfying such conditions lead to problems such as reduced performance due to redundant service execution, or permanent errors (composition mismatches), due to incompatible boundary conditions. Currently, the semantics of these boundary conditions are expressed in natural language only, making it impossible to incorporate them into an automatic analysis tool. Furthermore, early understanding of how components call each other would be necessary, but it is currently difficult to achieve by means of a tool, as the method dispatch rules in a component system differ from the dispatch rules of the programming language(s) in which they were developed. We have developed a metamodel, $${\mathbb{M}}$$ , for describing boundary conditions, an analysis method, $${\mathbb{A}}$$ , and a static component-level call graph extraction method for EJB applications, CHA EJB . $${\mathbb{A}}$$ uses $${\mathbb{M}}$$ models to analyze inter-component call graphs, and thus detect problems such as composition mismatches or redundancies, thus allowing for remedial action to take place. We present $${\mathbb{M}},{\mathbb{A}}$$ and CHA EJB in this article, show that $${\mathbb{A}}$$ produces correct results, and describe a prototype analysis tool implementing the three, which we used to validate our approach on two popular EJB applications. },
keywords={Software components - Contextual composition - Static analysis - Enterprise Java },
pdf={static verification.pdf},
}
</bibtex>
<bibtex>
@article{336,
author={Parsons,T.;Murphy,J.},
title={Detecting Performance Antipatterns in Component Based Enterprise Systems},
journal={Journal of Optical Technology},
year={2008},
pages={55-90(36 pages)},
volume={7(3)},
abstract={We introduce an approach for automatic detection of performance antipatterns. The approach is based on a number of advanced monitoring and analysis techniques. The advanced analysis is used to identify relationships and patterns in the monitored data. This information is subsequently used to reconstruct a design model of the underlying system, which is loaded into a rule engine in order to identify predefined antipatterns. We give results of applying this approach to identify a number of antipatterns in two JEE applications. Finally, this work also categorises JEE antipatterns into categories based on the data needed to detect them.},
keywords={Component Systems,Antipatterns},
pdf={detecting performance.pdf},
}
</bibtex>
<bibtex>
@article{405,
author={O.Ashagi;S.Murphy;L.Murphy},
title={Interference Mitigation in License-exempt 802.16 systems:a distributed approach},
journal={Unlicensed Mobile Access Technology},
year={2008},
pages={49-50},
volume={August },
abstract={Operating in license-exempt IEEE 802.16 wireless spectrum is a challenging research issue. The
research focus is on deriving intelligent algorithms to mitigate the interference that occurs between
different users. In this chapter, we propose an enhancement to our previously published distributed
approach to mitigate interference between 802.16 systems operating in close proximity, by introducing
a re-listening mechanism to determine whether there are more subcarriers available in the
channel than what the base stations (BSs) are currently using.
Simulation results show that the re-listening mechanism offers a 100 percent throughput
increase for some BSs. Our results also show the general trend of throughput variations between
the downlink and the uplink, due to the differences in transmission power.},
keywords={IEEE 802.16,},
pdf={interference.pdf},
}
</bibtex>
<bibtex>
@article{425,
author={C.H.Muntean},
title={Improving Learner Quality of Experience by Content Adaptation based on Network Conditions},
journal={Computers in Human Behaviour},
year={2008},
pages={1452-1472},
volume={24},
abstract={Apart from user characteristics, properties of the network over which the content is delivered and
device on which the content is displayed affect end-user perceived quality. This paper presents a learner
quality of experience (QoE) model that apart from the user-related content adaptation, considers
delivery performance-based content personalisation in order to improve user experience when interacting
with an online learning system.
A comparison-based study on the benefit of using the proposed learner QoE model in adaptive
and personalized education was conducted involving the original AHA! and QoEAHA – a version
of AHA! enhanced with the learner QoE model. Testing results demonstrate significant benefits in
terms of learning achievement, learning performance, learner navigation and user QoE in favour
of the learner QoE model-enhanced solution.},
keywords={QoE},
pdf={Muntean_2008_Computers-in-Human-Behavior.pdf},
}
</bibtex>
<bibtex>
@article{453,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={Open Corpus Architecture for Personalised Ubiquitous e-Learning},
journal={Personal & Ubiquitous Computing},
year={2008},
pages={197-205},
volume={13},
abstract={As the e-learning area matures, there are a
growing number of e-learning content providers that
produce and distribute material that covers a large range of
topics, differs in quality and is represented in various formats.
Lately, different devices and various network
technologies allow extensive user access to educational
content almost anywhere, anytime and from any device.
Ubiquitous e-learning has the potential to provide continuous
and context-based, educational material to human
learners anytime, anywhere and on any device. Since each
person has different expectations related to the content, the
performance of the delivery and display of that content, it
is desirable for an ubiquitous e-learning environment to
provide user-oriented personalisation of e-learning material.
However very often there are multiple sources of
e-learning material at various web locations (open corpus
resources) that cover the same topic, but differ in terms of
quality, formatting and even cost. It is very difficult for
learners to select the content that best suits their interests
and goals, characteristics of the device used and delivery
network as well as their cost budget. This paper proposes
an innovative ubiquitous e-learning environment called
Performance-based E-learning Adaptive Cost-efficient
Open Corpus frameworK (PEACOCK) that provides
support for the selection and distribution of personalised
e-learning rich media content (e.g. multimedia, pictures,
graphics and text) to e-learners such as it will best suit
users’ interests and goals, meet their formatting preferences
and cost constraints, while considering the limitations
introduced by the end-user devices and the delivery networks
to the user. PEACOCK’s main goal is to maximise
the users’ e-learning experience and increase their learning
satisfaction and learning outcome.},
keywords={Adaptive e-learning systems �},
pdf={open corpus.pdf},
}
</bibtex>
<bibtex>
@article{454,
author={Gabriel-Miro Muntean;G.Ghinea;T.N.Sheehan},
title={Region of Interest-based Adaptive Multimedia Streaming Scheme},
journal={IEEE Trans. on Broadcasting},
year={2008},
pages={296-303},
volume={54},
abstract={Adaptive multimedia streaming aims at adjusting
the transmitted content based on the available bandwidth such as
losses that often severely affect the end-user perceived quality are
minimized and consequently the transmission quality increases.
Current solutions affect equally the whole viewing area of the
multimedia frames, despite research showing that there are regions
on which the viewers are more interested in than on others.
This paper presents a novel region of interest-based adaptive
scheme (ROIAS) for multimedia streaming that when performing
transmission-related quality adjustments, selectively affects the
quality of those regions of the image the viewers are the least
interested in. As the quality of the regions the viewers are the
most interested in will not change (or will involve little change),
the proposed scheme provides higher overall end-user perceived
quality than any of the existing adaptive solutions.},
keywords={Content adaptation, multimedia streaming,},
pdf={region.pdf},
}
</bibtex>
<bibtex>
@article{455,
author={Gabriel-Miro Muntean;G.Ghinea;P.Frossard;M.Etoh;F.Speranza;H.R.Wu},
title={Advanced Solutions for Quality-Oriented Multimedia Broadcasting},
journal={IEEE Trans. on Broadcasting},
year={2008},
pages={494-498},
volume={54},
abstract={Multimedia content is increasingly being delivered
via different types of networks to viewers in a variety
of locations and contexts using a variety of devices. The ubiquitous
nature of multimedia services comes at a cost, however.
The successful delivery of multimedia services will require
overcoming numerous technological challenges many of which
have a direct effect on the quality of the multimedia experience.
For example, due to dynamically changing requirements and
networking conditions, the delivery of multimedia content
has traditionally adopted a best effort approach. However,
this approach has often led to the end-user perceived quality
of multimedia-based services being negatively affected. Yet
the quality of multimedia content is a vital issue for the
continued acceptance and proliferation of these services. Indeed,
end-users are becoming increasingly quality-aware in
their expectations of multimedia experience and demand an
ever-widening spectrum of rich multimedia-based services.},
keywords={Multimedia,Network},
pdf={advanced solution.pdf},
}
</bibtex>
<bibtex>
@article{399,
author={T.Taleb;A.Nafaa;L.Murphy;K.Hashimoto;N.Kato;Y.Nemoto},
title={Towards Efficient Service-Level QoS Provisioning in Large Scale 802.11-Based Networks},
journal={IEEE Network:Special Issue on Advances in Broadband Access Networks},
year={2007},
pages={42-48},
volume={21},
abstract={Along with recent advances in mobile networking and portable computing technologies,
there is a trend in the telecommunications industry toward the development
of efficient ubiquitous systems that can provide a set of bandwidth-intensive
and real-time services to multiple users while supporting their full mobility. Largescale
deployment of 802.11-based technologies will play an integral part in the
construction of such ubiquitous wireless mobile systems. A challenging task in the
development of such networks is efficient provisioning of QoS-enabled services for
mobile users. In this context, we propose a scheme that constantly monitors the
overall network performance to perform admission control and traffic conditioning
at the 802.11-based access points and mobile terminals. The focus is on servicelevel
fairness, where different flows from the same traffic class can still receive the
same QoS level even if they have different bit rates. Furthermore, given the mobility
of users, the success of any resource allocation and admission control model
depends on the continuity of QoS guarantees across different WLANs. This article
proposes a dynamic service level agreement negotiation protocol that allows
mobile terminals to perform handoffs between different WLANs while maintaining
the agreed level of service. End users also can change their service levels in
response to changes in network conditions.},
keywords={Internet,802.11,Wireless Mobile,QoS},
pdf={toward efficient.pdf},
}
</bibtex>
<bibtex>
@article{403,
author={G.Muntean;P.Perry;L.Murphy},
title={A Comparison Based Study of Quality Oriented Video on Demand},
journal={IEEE Transactions on Broadcasting},
year={2007},
pages={92-102},
volume={53},
abstract={The Quality Oriented Adaptation Scheme (QOAS) is
used for high bit-rate multimedia streaming in local broadband
multi-service all-IP networks. It balances two opposing goals:
providing high quality multimedia-based services to end-users, and
increasing the infrastructure utilisation and number of customers
simultaneously served. Extensive objective testing results presented
in this paper show that QOAS achieves high performance in terms of
end-user perceived quality, loss rate, throughput, link utilisation, and
number of customers simultaneously served. These results were
obtained even in highly loaded and variable delivery conditions
caused by traffic of different types, sizes, and variation patterns.
QOAS performance was assessed stand-alone and in comparison
with other existing solutions, adaptive and non-adaptive.},
keywords={Adaptive video streaming, feedback control, grading scheme, end-user perceived quality.},
pdf={a comparison.pdf},
}
</bibtex>
<bibtex>
@article{409,
author={C.H.Muntean;G.M.Muntean;J.McManis;A.I.Cristea},
title={Quality of Experience-LAOS:Create Once,Use Many,Use Anywhere},
journal={International Journal of Learning Technology},
year={2007},
pages={209-229},
volume={3},
abstract={This paper proposes QoE-LAOS, a Quality of Experience-oriented adaptive authoring model that enables performance-aware adaptation. It extends the existing LAOS authoring model in order to consider display and delivery performance issues. QoE-LAOS involves the addition of three new QoE sublayers: QoE Content Features sublayer, QoE Characteristics sublayer and QoE Rules sublayer. These proposed QoE sublayers are deployed at LAOS's Domain, Adaptation and Presentation Models, respectively. This paper formalises and exemplifies QoE-LAOS and discusses authoring-related issues in relation to each new sublayer. },
keywords={adaptive hypermedia, adaptive educational hypermedia, AEH, adaptive author assistance, semi-automatic adding, authoring models, authoring tools, adaptive web application engineering, adaptive web application authoring, adaptive learning, adaptive systems,},
pdf={quality of experience.pdf},
}
</bibtex>
<bibtex>
@article{396,
author={N.Cranley;L.Murphy},
title={Incorporating User Perception in Adaptive Video Streaming Systems},
journal={Digital Multimedia Perception & Design},
year={2006},
pages={860-861},
volume={May 2006},
abstract={There is an increasing demand for streaming video applications over both the fixed
Internet and wireless IP networks. The fluctuating bandwidth and time-varying delays
of best-effort networks makes providing good quality streaming a challenge. Many
adaptive video delivery mechanisms have been proposed over recent years; however,
most do not explicitly consider user-perceived quality when making adaptations, nor
do they define what quality is. This chapter describes research that proposes that an
optimal adaptation trajectory through the set of possible encodings exists, and
indicates how to adapt transmission in response to changes in network conditions in
order to maximize user-perceived quality.},
keywords={Video Streaming,Internet,IP Networks},
pdf={incorporating.pdf},
}
</bibtex>
<bibtex>
@article{410,
author={C.H.Muntean;J.McManis},
title={End-User Quality of Experience Oriented Adaptive E-learning System},
journal={Journal of Digital Information},
year={2006},
pages={1},
volume={7},
abstract={In the context of new devices and with a variety of network technologies that allow access to the Internet, the providers of e-learning materials have to ensure that the users have a positive experience using their e-learning systems and they are happy to re-use them. Adaptive Hypermedia research aims to provide personalised educational material that ensures a positive learning experience for the end-users. However, user experience is dependent not only on the content served to them, but also on the user perceived performance of the e-learning system. This leads to a new dimension of individual differences between Web users: the end-user Quality of Experience (QoE). We have proposed a solution for Adaptive Hypermedia Systems (AHS) that provides satisfactory end-user QoE through the use of a new QoE layer. This layer attempts to take into account multiple factors affecting QoE in relation to the delivery of a wide range of Web components such as text, images, video, audio.

The effectiveness of our QoE layer has been tested in comparison to a standard educational AHS and the results of these tests are presented in this paper. Different educational-based evaluation techniques such as learner achievement analysis, learning performance assessment, usability survey and correlation analysis between individual student performance and judgment on system usability were applied in order to fully assess the performance of the proposed QoE layer. Results of the tests showed that the use of the QoE layer brought significant improvements in terms of user learning performance, system usability and user satisfaction with the personalised e-learning system while not affecting the user learning achievement
},
keywords={end-user QoE, adaptive hypermedia, e-learning, end-user perceived performance, learning performance },
pdf={end user quality.doc},
}
</bibtex>
<bibtex>
@article{419,
author={N.Cranley;P.Perry;L.Murphy},
title={User Perception of Adapting Video Quality},
journal={International Journal of Human-Computer Studies/Knowledge Acquisition},
year={2006},
pages={637-647},
volume={64},
abstract={In general, video quality adaptation and video quality evaluation are distinct activities. Most adaptive delivery mechanisms for
streaming multimedia content do not explicitly consider user-perceived quality when making adaptation decisions. Equally, video quality
evaluation techniques are not designed to evaluate instantaneous quality where the quality is changing over time. We propose that an
Optimal Adaptation Trajectory (OAT) through the set of possible encoding exists, and that it indicates how to adapt encoding quality in
response to changes in network conditions in order to maximize user-perceived quality. The subjective and objective tests carried out to
find such trajectories for a number of different MPEG-4 video clips are described. Experimental subjective testing results are presented
that demonstrate the dynamic nature of user perception with adapting multimedia. The results demonstrate that adaptation using the
OAT out-performs conventional adaptation strategies in which only a single aspect of the video quality is adapted. In contrast, the OAT
provides a mechanism to adapt multiple aspects of the video quality thereby giving better user-perceived quality in both the short and
long term.},
keywords={Video quality; Evaluation/methodology; Perception; Subjective and objective quality; Adaptation},
pdf={user perception.pdf},
}
</bibtex>
<bibtex>
@article{420,
author={N.Cranley;L.Murphy;P.Perry},
title={Dynamic Content-Based Adaptation of Streamed Multimedia,Intelligence-based Adaptation for Ubiquitous Multimedia Communications},
journal={Journal of Network & Computer Applications},
year={2006},
pages={983-1006},
volume={30},
abstract={Most adaptive delivery mechanisms for streaming multimedia content do not explicitly
consider user-perceived quality when making adaptation decisions. We show that an optimal
adaptation trajectory (OAT) through the set of possible encodings exists, and that it indicates
how to adapt encoding quality in response to changes in network conditions in order to
maximise user-perceived quality. The OAT is related to the characteristics of the content, in
terms of spatial and temporal complexity. We describe a method to automatically determine
the OAT in response to the time-varying characteristics of the content. In this way, as the
characteristics of the content change over time, the system can dynamically and intelligently
adjust the adaptation process in order to maximise the user-perceived quality. The OAT can
be used with any sender-based transmission adaptation policy. We demonstrate content-based
adaptation using the OAT in a practical system using two different adaptation algorithms.
Furthermore, we show how this form of adaptation can result in differing adaptation
behaviour not only as a result of the dynamics of the content but also as a result of the
adaptation algorithm being used. Finally, we show how increased feedback frequency does not
necessarily improve the behaviour of the adaptation algorithm being used.},
keywords={User perception; Video quality; Adaptive systems; Multimedia},
pdf={dynamic.pdf},
}
</bibtex>
<bibtex>
@article{300,
author={Brebner,P.;Cecchet,E.;Marguerite,J.;Tuma,P.;Ciuhandu,O.;Dufour,B.;Eeckhout,L.;Frenot,S.;Krishna,A.S.;Murphy,J.;Verbrugge,C.},
title={Middleware Benchmarking:Approaches,Results,Experiences,},
journal={Concurrency & Computation-Practice & Experience},
year={2005},
pages={1799-1805(7 pages)},
volume={17(15)},
abstract={The report summarizes the results of the Workshop on Middleware Benchmarking held during OOPSLA
2003. The goal of the workshop was to help advance the current practice of gathering performance
characteristics of middleware implementations through benchmarking. The participants of the workshop
have focused on identifying requirements of and obstacles to middleware benchmarking and forming
a position on the related issues. Selected requirements and obstacles are presented, together with
guidelines to adhere to when benchmarking, open issues of current practice, and perspectives on further
research},
keywords={middleware benchmarking; middleware performance; middleware scalability; middleware evaluation; middleware benchmark design; benchmarking guidelines; benchmarking measurement; benchmarking metrics; OOPSLA 2003 workshop},
pdf={middleware benchmarking.pdf},
}
</bibtex>
<bibtex>
@article{308,
author={Klusek,B.;Murphy,J.;Barry,L.P.},
title={New Fiber Delay Line Usage Strategy in Optical Burst Switching Networks},
journal={Networks & Communication Systems},
year={2005},
pages={5 Pages},
volume={NCS 2005},
abstract={Optical Burst Switching (OBS) is a new paradigm for
future all-optical networks. In an OBS node, a Fiber
Delay Line may be used to delay a burst, effectively
increasing its offset time. Traditionally, FDLs were used
in contention resolution, i.e. a burst was only buffered if
it would otherwise been dropped. We propose a different
approach, where delay lines are used also to better arrange
bursts in time. In our strategy both outgoing channels
and FDL channels are assigned a price, according to their
suitability for a particular burst. When a control packet
arrives at a core node, all the possible ways of handling the
corresponding burst are found (the outgoing channel, with
or without a FDL), and the one with a lowest total price is
chosen. This makes it possible to use most FDL channels
for the majority of the time, reducing the probability of
future contention. We present simulation results, showing
how node performance depends on the size of a FDL bank,
using either Last Available Unused Channel with Void
Filling (LAUC-VF) and the traditional FDL usage strategy
or our algorithm.},
keywords={High-speed Internet, Optical Burst Switching, Fiber Delay Lines, burst scheduling},
pdf={new fiber.pdf},
}
</bibtex>
<bibtex>
@article{380,
author={G.Muntean;P.Perry;L.Murphy},
title={Subjective Assessment of the Quality-Oriented Adaptive Scheme},
journal={IEEE Transactions on Broadcasting},
year={2005},
pages={276-286},
volume={51},
abstract={The Quality-Oriented Adaptation Scheme (QOAS)
supports the distribution of high quality multimedia services
to a large number of simultaneous customers via given broadband
IP infrastructure. This paper presents subjective testing
results that augment previously reported objective performance
assessment. Clips representing different classes of multimedia
sequences in terms of motion content and types were selected
and streamed using a QOAS-based prototype system. Congested
delivery network conditions were emulated and the effects of the
consequent QOAS-driven adaptations were subjectively assessed
by end-users. The test subjects have also graded their perceived
quality when using a nonadaptive streaming approach. The
QOAS-related results were much higher than those obtained for
a nonadaptive approach, being above the “good” perceptual level
for all multimedia clips and in all tested delivery conditions.},
keywords={Adaptive multimedia streaming, end-user perceived quality, feedback control, subjective testing.},
pdf={subjective.pdf},
}
</bibtex>
<bibtex>
@article{382,
author={N.Cranley;P.Perry;L.Murphy},
title={Optium Adaptation Trajectories for Streamed Multimedia},
journal={ACM Multimedia Systems },
year={2005},
pages={392-401},
volume={10},
abstract={Most adaptive delivery mechanisms for streaming
multimedia content do not explicitly consider user-perceived
quality when making adaptations. We propose that an optimal
adaptation trajectory through the set of possible
encodings exists and that it indicates how to adapt encoding
quality in response to changes in network conditions to
maximize user-perceived quality. Such an optimum adaptation
trajectory can be used with any transmission adaptation
policy. We describe the subjective tests we carried out to
find such trajectories for a number of different MPEG-4
video clips and indicate how this knowledge could be used
in the operation of a practical system.},
keywords={Perceptual video quality · Adaptive multimedia transmission · Subjective testing · Video encoding},
pdf={optium adaptation.pdf},
}
</bibtex>
<bibtex>
@article{383,
author={M.Narbutt;A.Kelly;L.Murphy;P.Perry},
title={Adaptive VoIP playout Scheduling :A new method for assesing user satisfaction},
journal={IEEE Internet Computing},
year={2005},
pages={28-34},
volume={July 2005},
abstract={Delay and packet loss dramatically affect the quality of a voice-over-IP (VoIP) call
and depend on the playout buffer scheme implemented at the receiver. The
choice of playout algorithm can’t be based on statistical metrics without
considering the perceived end-to-end conversational speech quality. The authors
present a method for evaluating various playout algorithms that extends the Emodel
concept by estimating user satisfaction from time-varying transmission
impairments. This article evaluates several playout algorithms and shows a
correspondence between their results and those obtained via statistical loss and
delay metrics.},
keywords={Delay,Jitter,Packet Loss},
pdf={adaptive voip.pdf},
}
</bibtex>
<bibtex>
@article{285,
author={Dantcha,A.;Barry,L.;Murphy J.;Dunne,J.;Mullane,T.;Mcdonald,D.},
title={BER Performance in Wavelength Packet Switched WDM systems during Nano-Second Wavelength switching Events},
journal={Journal of Optical Communication},
year={2004},
pages={171-177(7Pages)},
volume={242},
abstract={An important characteristic of wavelength tuneable laser transmitters is that as
they tune between output wavelength channels they may generate light at a range of other
wavelengths. This effect may ultimately influence the design of WDM wavelength packetswitched
networks employing wavelength tuneable transmitters. We have investigated this
effect by examining the BER transmission performance of a WDM channel as a function
of the degree of attenuation of another WDM wavelength signal during fast wavelength
switching events. Our results show the importance of attenuating the output signal from
the wavelength switched laser in order to prevent performance degradations on the
monitored data channel.},
keywords={Optical communications, networks, wavelength division multiplexing, tuneable laser, packet switching, cross-channel interference},
pdf={ber performance.pdf},
}
</bibtex>
<bibtex>
@article{372,
author={G.Muntean;P.Perry;L.Murphy},
title={Performance Comparison of Local Area Video Streaming Systems},
journal={IEEE Communications Letters},
year={2004},
pages={326-328},
volume={8},
abstract={The performance of our Quality Oriented
Adaptation Scheme (QOAS) for multimedia streaming in local
networks is compared with other existing solutions (TFRCP,
LDA+, and non-adaptive). This comparison is done in terms of
bandwidth utilization, number of concurrent clients, loss rate,
and end-user perceived quality. Simulation results show that for
the same average end-user quality, our QOAS system can
accommodate a significantly higher number of simultaneous
clients while also having higher bandwidth utilization. For the
same number of clients, the average end-user quality is always
higher for QOAS than for the other solutions studied.},
keywords={Adaptive video streaming, feedback control, grading scheme, end-user quality.},
pdf={performance comparison.pdf},
}
</bibtex>
<bibtex>
@article{375,
author={G.Muntean;P.Perry;L.Murphy},
title={A New Adaptive Multimedia Streaming System for ALL-IP Multi Service Networks},
journal={IEEE Transactions on Broadcasting},
year={2004},
pages={1-10},
volume={50},
abstract={A significant challenge in all-IP multi-service networks
is to balance the goal of providing high-quality services to
the end-users with the desire to maximize the number of end-users
that can be simultaneously served. This paper presents a solution
to this challenge by using the Quality-Oriented Adaptation
Scheme (QOAS) for delivering multimedia streams. This adaptive
mechanism uses feedback from clients regarding the quality of
delivery to assist the server in making dynamic adjustments to
the transmitted streams. Experimental objective and subjective
test results illustrate the significant performance improvements
achieved by QOAS, both in terms of number of simultaneous
viewers served and of end-user perceived quality.},
keywords={Adaptive multimedia streaming, all-IP multi-service networks, dynamic feedback, grading scheme, statistical multiplexing.},
pdf={new adaptive.pdf},
}
</bibtex>
<bibtex>
@article{357,
author={G.Muntean;P.Perry;L.Murphy},
title={Quality Oriented Adaptation Scheme for Video-On-Demand},
journal={IEE Electronic Letters},
year={2003},
pages={1689-1690},
volume={39},
abstract={The QOAS system proposed in [1, 2] is used for MPEG2 Video-on-Demand (VoD) delivery in local
multi-service IP networks. QOAS balances the need for high end-user quality with increased network utilisation,
regardless of the nature of other cross traffic. A high utilisation would allow an increased number of customers to be
served from a limited infrastructure, minimising the costs, but decreasing the end-user quality. The goal of QOAS is
to maximise end-user perceived quality and links’ utilisation in the existing network conditions.
QOAS varies the transmitted quantity of video data by dynamically adjusting the quality of the streamed video. In
comparison with other approaches [3], its novelty is that these adjustments are carried out based on client-computed
quality scores that describe the current quality of delivery sent via regular feedback. These scores include shortterm
and long-term assessments of both the end-user perceived video quality [1] and IP performance
parameters (e.g. delay, jitter, loss rate). During transmission the video quality is varied in a controlled manner
according to the feedback reports. It requires fewer negative quality scores to trigger a quality decrease than positive
for an increase. This ensures a fast reaction during bad delivery conditions helping to eliminate their cause and
makes sure that quality upgrades are performed only after the network conditions have improved.},
keywords={MPEG,QoS,IP Networks},
pdf={quality oriented.pdf},
}
</bibtex>
<bibtex>
@article{415,
author={H.Melvin;L.Murphy},
title={Time Synchronization for VoIP Quality of Service},
journal={IEEE Internet Computing},
year={2002},
pages={6 Pages},
volume={25-26},
abstract={Although packet-based and unmanaged
networks like the Internet
are ideal for delivering timeinsensitive
data such as e-mail or static
Web traffic, the growing demand for
Web-based multimedia data exposes the
limitations of core Internet protocols.
With no end-to-end delay bounds, the
public Internet’s best-effort service is
unsuitable for delivering time-sensitive
data and for interactive applications such
as voice-over-IP.
Normal speech consists of talkspurts,
which typically last a few hundred milliseconds,
and silence periods, which
occur both within a spoken word and
between words. In a packet-based network,
voice packets are generated periodically
at the sender and transmitted across
the network. To cope with the packet
interarrival variance inherent in besteffort
service, current VoIP implementations
generally implement fixed buffer
schemes. Fixed buffer schemes make no
attempt to match receiver operation to
current network performance. An alternative
approach is to use a more complex
adaptive buffer scheme. This continuously
matches playout delay to network conditions,
at the expense of some packet
loss due to late arrivals and some distortion
of intertalkspurt silence periods.
Various approaches seek to optimize
the quality of service of VoIP applications
(see the sidebar, “Quality of Service for
VoIP,” next page, for a categorization of
QoS approaches). We propose a system
that uses synchronized time to combine
the useful characteristics of both fixed
and adaptive buffer strategies, thereby
improving VoIP quality of service. Using
a combination of global positioning system
(GPS) technologies and the network
time protocol (NTP), hosts can learn the
precise end-to-end delay for each packet.
This information can benefit both domestic
and business Internet telephony users.
In this article, we outline our proposed
system and discuss issues arising from the
use of synchronized time.},
keywords={Web Traffic,Web-based Multimedia,VoIP},
pdf={time.pdf},
}
</bibtex>

Pubs:journal

2012-03-09T13:08:28Z

Root: Created page with "<bibtex> @article{415, author={H.Melvin;L.Murphy}, title={Time Synchronization for VoIP Quality of Service}, journal={IEEE Internet Computing}, year={2002}, pages={6 Pages}, volu..."

<bibtex>
@article{415,
author={H.Melvin;L.Murphy},
title={Time Synchronization for VoIP Quality of Service},
journal={IEEE Internet Computing},
year={2002},
pages={6 Pages},
volume={25-26},
abstract={Although packet-based and unmanaged
networks like the Internet
are ideal for delivering timeinsensitive
data such as e-mail or static
Web traffic, the growing demand for
Web-based multimedia data exposes the
limitations of core Internet protocols.
With no end-to-end delay bounds, the
public Internet’s best-effort service is
unsuitable for delivering time-sensitive
data and for interactive applications such
as voice-over-IP.
Normal speech consists of talkspurts,
which typically last a few hundred milliseconds,
and silence periods, which
occur both within a spoken word and
between words. In a packet-based network,
voice packets are generated periodically
at the sender and transmitted across
the network. To cope with the packet
interarrival variance inherent in besteffort
service, current VoIP implementations
generally implement fixed buffer
schemes. Fixed buffer schemes make no
attempt to match receiver operation to
current network performance. An alternative
approach is to use a more complex
adaptive buffer scheme. This continuously
matches playout delay to network conditions,
at the expense of some packet
loss due to late arrivals and some distortion
of intertalkspurt silence periods.
Various approaches seek to optimize
the quality of service of VoIP applications
(see the sidebar, “Quality of Service for
VoIP,” next page, for a categorization of
QoS approaches). We propose a system
that uses synchronized time to combine
the useful characteristics of both fixed
and adaptive buffer strategies, thereby
improving VoIP quality of service. Using
a combination of global positioning system
(GPS) technologies and the network
time protocol (NTP), hosts can learn the
precise end-to-end delay for each packet.
This information can benefit both domestic
and business Internet telephony users.
In this article, we outline our proposed
system and discuss issues arising from the
use of synchronized time.},
keywords={Web Traffic,Web-based Multimedia,VoIP},
pdf={time.pdf},
}
</bibtex>
<bibtex>
@article{357,
author={G.Muntean;P.Perry;L.Murphy},
title={Quality Oriented Adaptation Scheme for Video-On-Demand},
journal={IEE Electronic Letters},
year={2003},
pages={1689-1690},
volume={39},
abstract={The QOAS system proposed in [1, 2] is used for MPEG2 Video-on-Demand (VoD) delivery in local
multi-service IP networks. QOAS balances the need for high end-user quality with increased network utilisation,
regardless of the nature of other cross traffic. A high utilisation would allow an increased number of customers to be
served from a limited infrastructure, minimising the costs, but decreasing the end-user quality. The goal of QOAS is
to maximise end-user perceived quality and links’ utilisation in the existing network conditions.
QOAS varies the transmitted quantity of video data by dynamically adjusting the quality of the streamed video. In
comparison with other approaches [3], its novelty is that these adjustments are carried out based on client-computed
quality scores that describe the current quality of delivery sent via regular feedback. These scores include shortterm
and long-term assessments of both the end-user perceived video quality [1] and IP performance
parameters (e.g. delay, jitter, loss rate). During transmission the video quality is varied in a controlled manner
according to the feedback reports. It requires fewer negative quality scores to trigger a quality decrease than positive
for an increase. This ensures a fast reaction during bad delivery conditions helping to eliminate their cause and
makes sure that quality upgrades are performed only after the network conditions have improved.},
keywords={MPEG,QoS,IP Networks},
pdf={quality oriented.pdf},
}
</bibtex>
<bibtex>
@article{285,
author={Dantcha,A.;Barry,L.;Murphy J.;Dunne,J.;Mullane,T.;Mcdonald,D.},
title={BER Performance in Wavelength Packet Switched WDM systems during Nano-Second Wavelength switching Events},
journal={Journal of Optical Communication},
year={2004},
pages={171-177(7Pages)},
volume={242},
abstract={An important characteristic of wavelength tuneable laser transmitters is that as
they tune between output wavelength channels they may generate light at a range of other
wavelengths. This effect may ultimately influence the design of WDM wavelength packetswitched
networks employing wavelength tuneable transmitters. We have investigated this
effect by examining the BER transmission performance of a WDM channel as a function
of the degree of attenuation of another WDM wavelength signal during fast wavelength
switching events. Our results show the importance of attenuating the output signal from
the wavelength switched laser in order to prevent performance degradations on the
monitored data channel.},
keywords={Optical communications, networks, wavelength division multiplexing, tuneable laser, packet switching, cross-channel interference},
pdf={ber performance.pdf},
}
</bibtex>
<bibtex>
@article{372,
author={G.Muntean;P.Perry;L.Murphy},
title={Performance Comparison of Local Area Video Streaming Systems},
journal={IEEE Communications Letters},
year={2004},
pages={326-328},
volume={8},
abstract={The performance of our Quality Oriented
Adaptation Scheme (QOAS) for multimedia streaming in local
networks is compared with other existing solutions (TFRCP,
LDA+, and non-adaptive). This comparison is done in terms of
bandwidth utilization, number of concurrent clients, loss rate,
and end-user perceived quality. Simulation results show that for
the same average end-user quality, our QOAS system can
accommodate a significantly higher number of simultaneous
clients while also having higher bandwidth utilization. For the
same number of clients, the average end-user quality is always
higher for QOAS than for the other solutions studied.},
keywords={Adaptive video streaming, feedback control, grading scheme, end-user quality.},
pdf={performance comparison.pdf},
}
</bibtex>
<bibtex>
@article{375,
author={G.Muntean;P.Perry;L.Murphy},
title={A New Adaptive Multimedia Streaming System for ALL-IP Multi Service Networks},
journal={IEEE Transactions on Broadcasting},
year={2004},
pages={1-10},
volume={50},
abstract={A significant challenge in all-IP multi-service networks
is to balance the goal of providing high-quality services to
the end-users with the desire to maximize the number of end-users
that can be simultaneously served. This paper presents a solution
to this challenge by using the Quality-Oriented Adaptation
Scheme (QOAS) for delivering multimedia streams. This adaptive
mechanism uses feedback from clients regarding the quality of
delivery to assist the server in making dynamic adjustments to
the transmitted streams. Experimental objective and subjective
test results illustrate the significant performance improvements
achieved by QOAS, both in terms of number of simultaneous
viewers served and of end-user perceived quality.},
keywords={Adaptive multimedia streaming, all-IP multi-service networks, dynamic feedback, grading scheme, statistical multiplexing.},
pdf={new adaptive.pdf},
}
</bibtex>
<bibtex>
@article{300,
author={Brebner,P.;Cecchet,E.;Marguerite,J.;Tuma,P.;Ciuhandu,O.;Dufour,B.;Eeckhout,L.;Frenot,S.;Krishna,A.S.;Murphy,J.;Verbrugge,C.},
title={Middleware Benchmarking:Approaches,Results,Experiences,},
journal={Concurrency & Computation-Practice & Experience},
year={2005},
pages={1799-1805(7 pages)},
volume={17(15)},
abstract={The report summarizes the results of the Workshop on Middleware Benchmarking held during OOPSLA
2003. The goal of the workshop was to help advance the current practice of gathering performance
characteristics of middleware implementations through benchmarking. The participants of the workshop
have focused on identifying requirements of and obstacles to middleware benchmarking and forming
a position on the related issues. Selected requirements and obstacles are presented, together with
guidelines to adhere to when benchmarking, open issues of current practice, and perspectives on further
research},
keywords={middleware benchmarking; middleware performance; middleware scalability; middleware evaluation; middleware benchmark design; benchmarking guidelines; benchmarking measurement; benchmarking metrics; OOPSLA 2003 workshop},
pdf={middleware benchmarking.pdf},
}
</bibtex>
<bibtex>
@article{308,
author={Klusek,B.;Murphy,J.;Barry,L.P.},
title={New Fiber Delay Line Usage Strategy in Optical Burst Switching Networks},
journal={Networks & Communication Systems},
year={2005},
pages={5 Pages},
volume={NCS 2005},
abstract={Optical Burst Switching (OBS) is a new paradigm for
future all-optical networks. In an OBS node, a Fiber
Delay Line may be used to delay a burst, effectively
increasing its offset time. Traditionally, FDLs were used
in contention resolution, i.e. a burst was only buffered if
it would otherwise been dropped. We propose a different
approach, where delay lines are used also to better arrange
bursts in time. In our strategy both outgoing channels
and FDL channels are assigned a price, according to their
suitability for a particular burst. When a control packet
arrives at a core node, all the possible ways of handling the
corresponding burst are found (the outgoing channel, with
or without a FDL), and the one with a lowest total price is
chosen. This makes it possible to use most FDL channels
for the majority of the time, reducing the probability of
future contention. We present simulation results, showing
how node performance depends on the size of a FDL bank,
using either Last Available Unused Channel with Void
Filling (LAUC-VF) and the traditional FDL usage strategy
or our algorithm.},
keywords={High-speed Internet, Optical Burst Switching, Fiber Delay Lines, burst scheduling},
pdf={new fiber.pdf},
}
</bibtex>
<bibtex>
@article{380,
author={G.Muntean;P.Perry;L.Murphy},
title={Subjective Assessment of the Quality-Oriented Adaptive Scheme},
journal={IEEE Transactions on Broadcasting},
year={2005},
pages={276-286},
volume={51},
abstract={The Quality-Oriented Adaptation Scheme (QOAS)
supports the distribution of high quality multimedia services
to a large number of simultaneous customers via given broadband
IP infrastructure. This paper presents subjective testing
results that augment previously reported objective performance
assessment. Clips representing different classes of multimedia
sequences in terms of motion content and types were selected
and streamed using a QOAS-based prototype system. Congested
delivery network conditions were emulated and the effects of the
consequent QOAS-driven adaptations were subjectively assessed
by end-users. The test subjects have also graded their perceived
quality when using a nonadaptive streaming approach. The
QOAS-related results were much higher than those obtained for
a nonadaptive approach, being above the “good” perceptual level
for all multimedia clips and in all tested delivery conditions.},
keywords={Adaptive multimedia streaming, end-user perceived quality, feedback control, subjective testing.},
pdf={subjective.pdf},
}
</bibtex>
<bibtex>
@article{382,
author={N.Cranley;P.Perry;L.Murphy},
title={Optium Adaptation Trajectories for Streamed Multimedia},
journal={ACM Multimedia Systems },
year={2005},
pages={392-401},
volume={10},
abstract={Most adaptive delivery mechanisms for streaming
multimedia content do not explicitly consider user-perceived
quality when making adaptations. We propose that an optimal
adaptation trajectory through the set of possible
encodings exists and that it indicates how to adapt encoding
quality in response to changes in network conditions to
maximize user-perceived quality. Such an optimum adaptation
trajectory can be used with any transmission adaptation
policy. We describe the subjective tests we carried out to
find such trajectories for a number of different MPEG-4
video clips and indicate how this knowledge could be used
in the operation of a practical system.},
keywords={Perceptual video quality · Adaptive multimedia transmission · Subjective testing · Video encoding},
pdf={optium adaptation.pdf},
}
</bibtex>
<bibtex>
@article{383,
author={M.Narbutt;A.Kelly;L.Murphy;P.Perry},
title={Adaptive VoIP playout Scheduling :A new method for assesing user satisfaction},
journal={IEEE Internet Computing},
year={2005},
pages={28-34},
volume={July 2005},
abstract={Delay and packet loss dramatically affect the quality of a voice-over-IP (VoIP) call
and depend on the playout buffer scheme implemented at the receiver. The
choice of playout algorithm can’t be based on statistical metrics without
considering the perceived end-to-end conversational speech quality. The authors
present a method for evaluating various playout algorithms that extends the Emodel
concept by estimating user satisfaction from time-varying transmission
impairments. This article evaluates several playout algorithms and shows a
correspondence between their results and those obtained via statistical loss and
delay metrics.},
keywords={Delay,Jitter,Packet Loss},
pdf={adaptive voip.pdf},
}
</bibtex>
<bibtex>
@article{396,
author={N.Cranley;L.Murphy},
title={Incorporating User Perception in Adaptive Video Streaming Systems},
journal={Digital Multimedia Perception & Design},
year={2006},
pages={860-861},
volume={May 2006},
abstract={There is an increasing demand for streaming video applications over both the fixed
Internet and wireless IP networks. The fluctuating bandwidth and time-varying delays
of best-effort networks makes providing good quality streaming a challenge. Many
adaptive video delivery mechanisms have been proposed over recent years; however,
most do not explicitly consider user-perceived quality when making adaptations, nor
do they define what quality is. This chapter describes research that proposes that an
optimal adaptation trajectory through the set of possible encodings exists, and
indicates how to adapt transmission in response to changes in network conditions in
order to maximize user-perceived quality.},
keywords={Video Streaming,Internet,IP Networks},
pdf={incorporating.pdf},
}
</bibtex>
<bibtex>
@article{410,
author={C.H.Muntean;J.McManis},
title={End-User Quality of Experience Oriented Adaptive E-learning System},
journal={Journal of Digital Information},
year={2006},
pages={1},
volume={7},
abstract={In the context of new devices and with a variety of network technologies that allow access to the Internet, the providers of e-learning materials have to ensure that the users have a positive experience using their e-learning systems and they are happy to re-use them. Adaptive Hypermedia research aims to provide personalised educational material that ensures a positive learning experience for the end-users. However, user experience is dependent not only on the content served to them, but also on the user perceived performance of the e-learning system. This leads to a new dimension of individual differences between Web users: the end-user Quality of Experience (QoE). We have proposed a solution for Adaptive Hypermedia Systems (AHS) that provides satisfactory end-user QoE through the use of a new QoE layer. This layer attempts to take into account multiple factors affecting QoE in relation to the delivery of a wide range of Web components such as text, images, video, audio.

The effectiveness of our QoE layer has been tested in comparison to a standard educational AHS and the results of these tests are presented in this paper. Different educational-based evaluation techniques such as learner achievement analysis, learning performance assessment, usability survey and correlation analysis between individual student performance and judgment on system usability were applied in order to fully assess the performance of the proposed QoE layer. Results of the tests showed that the use of the QoE layer brought significant improvements in terms of user learning performance, system usability and user satisfaction with the personalised e-learning system while not affecting the user learning achievement
},
keywords={end-user QoE, adaptive hypermedia, e-learning, end-user perceived performance, learning performance },
pdf={end user quality.doc},
}
</bibtex>
<bibtex>
@article{419,
author={N.Cranley;P.Perry;L.Murphy},
title={User Perception of Adapting Video Quality},
journal={International Journal of Human-Computer Studies/Knowledge Acquisition},
year={2006},
pages={637-647},
volume={64},
abstract={In general, video quality adaptation and video quality evaluation are distinct activities. Most adaptive delivery mechanisms for
streaming multimedia content do not explicitly consider user-perceived quality when making adaptation decisions. Equally, video quality
evaluation techniques are not designed to evaluate instantaneous quality where the quality is changing over time. We propose that an
Optimal Adaptation Trajectory (OAT) through the set of possible encoding exists, and that it indicates how to adapt encoding quality in
response to changes in network conditions in order to maximize user-perceived quality. The subjective and objective tests carried out to
find such trajectories for a number of different MPEG-4 video clips are described. Experimental subjective testing results are presented
that demonstrate the dynamic nature of user perception with adapting multimedia. The results demonstrate that adaptation using the
OAT out-performs conventional adaptation strategies in which only a single aspect of the video quality is adapted. In contrast, the OAT
provides a mechanism to adapt multiple aspects of the video quality thereby giving better user-perceived quality in both the short and
long term.},
keywords={Video quality; Evaluation/methodology; Perception; Subjective and objective quality; Adaptation},
pdf={user perception.pdf},
}
</bibtex>
<bibtex>
@article{420,
author={N.Cranley;L.Murphy;P.Perry},
title={Dynamic Content-Based Adaptation of Streamed Multimedia,Intelligence-based Adaptation for Ubiquitous Multimedia Communications},
journal={Journal of Network & Computer Applications},
year={2006},
pages={983-1006},
volume={30},
abstract={Most adaptive delivery mechanisms for streaming multimedia content do not explicitly
consider user-perceived quality when making adaptation decisions. We show that an optimal
adaptation trajectory (OAT) through the set of possible encodings exists, and that it indicates
how to adapt encoding quality in response to changes in network conditions in order to
maximise user-perceived quality. The OAT is related to the characteristics of the content, in
terms of spatial and temporal complexity. We describe a method to automatically determine
the OAT in response to the time-varying characteristics of the content. In this way, as the
characteristics of the content change over time, the system can dynamically and intelligently
adjust the adaptation process in order to maximise the user-perceived quality. The OAT can
be used with any sender-based transmission adaptation policy. We demonstrate content-based
adaptation using the OAT in a practical system using two different adaptation algorithms.
Furthermore, we show how this form of adaptation can result in differing adaptation
behaviour not only as a result of the dynamics of the content but also as a result of the
adaptation algorithm being used. Finally, we show how increased feedback frequency does not
necessarily improve the behaviour of the adaptation algorithm being used.},
keywords={User perception; Video quality; Adaptive systems; Multimedia},
pdf={dynamic.pdf},
}
</bibtex>
<bibtex>
@article{399,
author={T.Taleb;A.Nafaa;L.Murphy;K.Hashimoto;N.Kato;Y.Nemoto},
title={Towards Efficient Service-Level QoS Provisioning in Large Scale 802.11-Based Networks},
journal={IEEE Network:Special Issue on Advances in Broadband Access Networks},
year={2007},
pages={42-48},
volume={21},
abstract={Along with recent advances in mobile networking and portable computing technologies,
there is a trend in the telecommunications industry toward the development
of efficient ubiquitous systems that can provide a set of bandwidth-intensive
and real-time services to multiple users while supporting their full mobility. Largescale
deployment of 802.11-based technologies will play an integral part in the
construction of such ubiquitous wireless mobile systems. A challenging task in the
development of such networks is efficient provisioning of QoS-enabled services for
mobile users. In this context, we propose a scheme that constantly monitors the
overall network performance to perform admission control and traffic conditioning
at the 802.11-based access points and mobile terminals. The focus is on servicelevel
fairness, where different flows from the same traffic class can still receive the
same QoS level even if they have different bit rates. Furthermore, given the mobility
of users, the success of any resource allocation and admission control model
depends on the continuity of QoS guarantees across different WLANs. This article
proposes a dynamic service level agreement negotiation protocol that allows
mobile terminals to perform handoffs between different WLANs while maintaining
the agreed level of service. End users also can change their service levels in
response to changes in network conditions.},
keywords={Internet,802.11,Wireless Mobile,QoS},
pdf={toward efficient.pdf},
}
</bibtex>
<bibtex>
@article{403,
author={G.Muntean;P.Perry;L.Murphy},
title={A Comparison Based Study of Quality Oriented Video on Demand},
journal={IEEE Transactions on Broadcasting},
year={2007},
pages={92-102},
volume={53},
abstract={The Quality Oriented Adaptation Scheme (QOAS) is
used for high bit-rate multimedia streaming in local broadband
multi-service all-IP networks. It balances two opposing goals:
providing high quality multimedia-based services to end-users, and
increasing the infrastructure utilisation and number of customers
simultaneously served. Extensive objective testing results presented
in this paper show that QOAS achieves high performance in terms of
end-user perceived quality, loss rate, throughput, link utilisation, and
number of customers simultaneously served. These results were
obtained even in highly loaded and variable delivery conditions
caused by traffic of different types, sizes, and variation patterns.
QOAS performance was assessed stand-alone and in comparison
with other existing solutions, adaptive and non-adaptive.},
keywords={Adaptive video streaming, feedback control, grading scheme, end-user perceived quality.},
pdf={a comparison.pdf},
}
</bibtex>
<bibtex>
@article{409,
author={C.H.Muntean;G.M.Muntean;J.McManis;A.I.Cristea},
title={Quality of Experience-LAOS:Create Once,Use Many,Use Anywhere},
journal={International Journal of Learning Technology},
year={2007},
pages={209-229},
volume={3},
abstract={This paper proposes QoE-LAOS, a Quality of Experience-oriented adaptive authoring model that enables performance-aware adaptation. It extends the existing LAOS authoring model in order to consider display and delivery performance issues. QoE-LAOS involves the addition of three new QoE sublayers: QoE Content Features sublayer, QoE Characteristics sublayer and QoE Rules sublayer. These proposed QoE sublayers are deployed at LAOS's Domain, Adaptation and Presentation Models, respectively. This paper formalises and exemplifies QoE-LAOS and discusses authoring-related issues in relation to each new sublayer. },
keywords={adaptive hypermedia, adaptive educational hypermedia, AEH, adaptive author assistance, semi-automatic adding, authoring models, authoring tools, adaptive web application engineering, adaptive web application authoring, adaptive learning, adaptive systems,},
pdf={quality of experience.pdf},
}
</bibtex>
<bibtex>
@article{220,
author={A. Nafaa; S. Murphy; L. Murphy},
title={Analysis of a Large-Scale VOD Architecture for Broadband Operators: A P2P-Based Solution},
journal={IEEE Communications Magazine},
year={2008},
pages={47-55},
volume={46},
abstract={VOD services distribution is gaining unprecedented interest from the consumer communication industry due to its growing success in both the Internet and residential broadband market. In this article we present a scalable VOD distribution architecture for broadband operators. The solution is based on a P2P streaming concept in which a VOD streaming session requested by a given STB (Set-Top-Box) is actually provisioned via a multisource streaming session. This solution has the advantage of scaling naturally with the number of STBs in the network. In this article we focus on efficiently translating the popularity distribution into content availability in the network. Different aspects related to this issue are analyzed and challenges highlighted.
},
keywords={video on demand, peer-to-peer, popularity distribution, content availability},
}
</bibtex>
<bibtex>
@article{221,
author={Y. Qiao; E. Fallon; J. Murphy; L. Murphy; X. Zhu; G. Hayes; A. Matthews; A. Hanley},
title={Performance Analysis of Multi-homed Transport Protocols with Network Failure Tolerance},
journal={IET Communications},
year={2008},
pages={336-345},
volume={2},
abstract={This paper studies the performance of multi-homed transport protocols tolerant of network failure. It evaluates the performance of different retransmission policies combined with path failure detection thresholds, infinite or finite receive buffers for various path bandwidths, delays and loss rate conditions through SCTP simulation. The results show that retransmission policies perform differently with different path failure detection threshold configurations. It identifies that retransmission of all data on an alternate path with the path failure detection threshold set to zero performs best in symmetric path conditions but its performance degrades acutely in asymmetric path conditions even when the alternate path delay is shorter than the primary path delay. It illustrates that retransmission of all data on the same path with the path failure detection threshold set to one or zero gives the most stable performance in all path configurations.
},
keywords={Fault-tolerant computing, transport protocols},
pdf={performance analysis.pdf},
}
</bibtex>
<bibtex>
@article{222,
author={A. Nafaa; T. Taleb; L. Murphy},
title={Forward Error Correction Strategies for Media Streaming over Wireless Networks},
journal={IEEE Communications Magazine},
year={2008},
pages={72-79},
volume={46},
abstract={The success of next-generation mobile communication systems depends on the ability of service providers to engineer new added-value multimedia-rich services, which impose stringent constraints on the underlying delivery/transport architecture. The reliability of real-time services is essential for the viability of any such service offering. The sporadic packet loss typical of wireless channels can be addressed using appropriate techniques such as the widely-used packet-level Forward Error Correction. In designing channel-aware media streaming applications, two interrelated and challenging issues should be tackled: accuracy of characterizing channel fluctuations and effectiveness of application-level adaptation. The first challenge requires thorough insight into channel fluctuations and their manifestations at the application level, while the second concerns the way those fluctuations are interpreted and dealt with by adaptive mechanisms such as FEC. In this article we review the major issues that arise when designing a reliable media streaming system for wireless networks.
},
keywords={Forward error correction, multimedia streaming, wireless channel conditions},
}
</bibtex>
<bibtex>
@article{334,
author={Trofin,M.;Murphy,J.},
title={Static Verification of Component Composition in Contextual Composition Frameworks},
journal={International Journal on Software Tools for Technology Transfers},
year={2008},
pages={247-261(15 pages)},
volume={10(3)},
abstract={Contextual component frameworks, such as Enterprise JavaBeans (EJB), allow for components to specify boundary conditions for the runtime context. These conditions are satisfied at runtime by services of the underlying platform, thus ensuring that the context in which components run exhibits properties that allow them to operate correctly. Depending on how components call each other, it is possible that satisfying such conditions lead to problems such as reduced performance due to redundant service execution, or permanent errors (composition mismatches), due to incompatible boundary conditions. Currently, the semantics of these boundary conditions are expressed in natural language only, making it impossible to incorporate them into an automatic analysis tool. Furthermore, early understanding of how components call each other would be necessary, but it is currently difficult to achieve by means of a tool, as the method dispatch rules in a component system differ from the dispatch rules of the programming language(s) in which they were developed. We have developed a metamodel, $${\mathbb{M}}$$ , for describing boundary conditions, an analysis method, $${\mathbb{A}}$$ , and a static component-level call graph extraction method for EJB applications, CHA EJB . $${\mathbb{A}}$$ uses $${\mathbb{M}}$$ models to analyze inter-component call graphs, and thus detect problems such as composition mismatches or redundancies, thus allowing for remedial action to take place. We present $${\mathbb{M}},{\mathbb{A}}$$ and CHA EJB in this article, show that $${\mathbb{A}}$$ produces correct results, and describe a prototype analysis tool implementing the three, which we used to validate our approach on two popular EJB applications. },
keywords={Software components - Contextual composition - Static analysis - Enterprise Java },
pdf={static verification.pdf},
}
</bibtex>
<bibtex>
@article{336,
author={Parsons,T.;Murphy,J.},
title={Detecting Performance Antipatterns in Component Based Enterprise Systems},
journal={Journal of Optical Technology},
year={2008},
pages={55-90(36 pages)},
volume={7(3)},
abstract={We introduce an approach for automatic detection of performance antipatterns. The approach is based on a number of advanced monitoring and analysis techniques. The advanced analysis is used to identify relationships and patterns in the monitored data. This information is subsequently used to reconstruct a design model of the underlying system, which is loaded into a rule engine in order to identify predefined antipatterns. We give results of applying this approach to identify a number of antipatterns in two JEE applications. Finally, this work also categorises JEE antipatterns into categories based on the data needed to detect them.},
keywords={Component Systems,Antipatterns},
pdf={detecting performance.pdf},
}
</bibtex>
<bibtex>
@article{405,
author={O.Ashagi;S.Murphy;L.Murphy},
title={Interference Mitigation in License-exempt 802.16 systems:a distributed approach},
journal={Unlicensed Mobile Access Technology},
year={2008},
pages={49-50},
volume={August },
abstract={Operating in license-exempt IEEE 802.16 wireless spectrum is a challenging research issue. The
research focus is on deriving intelligent algorithms to mitigate the interference that occurs between
different users. In this chapter, we propose an enhancement to our previously published distributed
approach to mitigate interference between 802.16 systems operating in close proximity, by introducing
a re-listening mechanism to determine whether there are more subcarriers available in the
channel than what the base stations (BSs) are currently using.
Simulation results show that the re-listening mechanism offers a 100 percent throughput
increase for some BSs. Our results also show the general trend of throughput variations between
the downlink and the uplink, due to the differences in transmission power.},
keywords={IEEE 802.16,},
pdf={interference.pdf},
}
</bibtex>
<bibtex>
@article{425,
author={C.H.Muntean},
title={Improving Learner Quality of Experience by Content Adaptation based on Network Conditions},
journal={Computers in Human Behaviour},
year={2008},
pages={1452-1472},
volume={24},
abstract={Apart from user characteristics, properties of the network over which the content is delivered and
device on which the content is displayed affect end-user perceived quality. This paper presents a learner
quality of experience (QoE) model that apart from the user-related content adaptation, considers
delivery performance-based content personalisation in order to improve user experience when interacting
with an online learning system.
A comparison-based study on the benefit of using the proposed learner QoE model in adaptive
and personalized education was conducted involving the original AHA! and QoEAHA – a version
of AHA! enhanced with the learner QoE model. Testing results demonstrate significant benefits in
terms of learning achievement, learning performance, learner navigation and user QoE in favour
of the learner QoE model-enhanced solution.},
keywords={QoE},
pdf={Muntean_2008_Computers-in-Human-Behavior.pdf},
}
</bibtex>
<bibtex>
@article{453,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={Open Corpus Architecture for Personalised Ubiquitous e-Learning},
journal={Personal & Ubiquitous Computing},
year={2008},
pages={197-205},
volume={13},
abstract={As the e-learning area matures, there are a
growing number of e-learning content providers that
produce and distribute material that covers a large range of
topics, differs in quality and is represented in various formats.
Lately, different devices and various network
technologies allow extensive user access to educational
content almost anywhere, anytime and from any device.
Ubiquitous e-learning has the potential to provide continuous
and context-based, educational material to human
learners anytime, anywhere and on any device. Since each
person has different expectations related to the content, the
performance of the delivery and display of that content, it
is desirable for an ubiquitous e-learning environment to
provide user-oriented personalisation of e-learning material.
However very often there are multiple sources of
e-learning material at various web locations (open corpus
resources) that cover the same topic, but differ in terms of
quality, formatting and even cost. It is very difficult for
learners to select the content that best suits their interests
and goals, characteristics of the device used and delivery
network as well as their cost budget. This paper proposes
an innovative ubiquitous e-learning environment called
Performance-based E-learning Adaptive Cost-efficient
Open Corpus frameworK (PEACOCK) that provides
support for the selection and distribution of personalised
e-learning rich media content (e.g. multimedia, pictures,
graphics and text) to e-learners such as it will best suit
users’ interests and goals, meet their formatting preferences
and cost constraints, while considering the limitations
introduced by the end-user devices and the delivery networks
to the user. PEACOCK’s main goal is to maximise
the users’ e-learning experience and increase their learning
satisfaction and learning outcome.},
keywords={Adaptive e-learning systems �},
pdf={open corpus.pdf},
}
</bibtex>
<bibtex>
@article{454,
author={Gabriel-Miro Muntean;G.Ghinea;T.N.Sheehan},
title={Region of Interest-based Adaptive Multimedia Streaming Scheme},
journal={IEEE Trans. on Broadcasting},
year={2008},
pages={296-303},
volume={54},
abstract={Adaptive multimedia streaming aims at adjusting
the transmitted content based on the available bandwidth such as
losses that often severely affect the end-user perceived quality are
minimized and consequently the transmission quality increases.
Current solutions affect equally the whole viewing area of the
multimedia frames, despite research showing that there are regions
on which the viewers are more interested in than on others.
This paper presents a novel region of interest-based adaptive
scheme (ROIAS) for multimedia streaming that when performing
transmission-related quality adjustments, selectively affects the
quality of those regions of the image the viewers are the least
interested in. As the quality of the regions the viewers are the
most interested in will not change (or will involve little change),
the proposed scheme provides higher overall end-user perceived
quality than any of the existing adaptive solutions.},
keywords={Content adaptation, multimedia streaming,},
pdf={region.pdf},
}
</bibtex>
<bibtex>
@article{455,
author={Gabriel-Miro Muntean;G.Ghinea;P.Frossard;M.Etoh;F.Speranza;H.R.Wu},
title={Advanced Solutions for Quality-Oriented Multimedia Broadcasting},
journal={IEEE Trans. on Broadcasting},
year={2008},
pages={494-498},
volume={54},
abstract={Multimedia content is increasingly being delivered
via different types of networks to viewers in a variety
of locations and contexts using a variety of devices. The ubiquitous
nature of multimedia services comes at a cost, however.
The successful delivery of multimedia services will require
overcoming numerous technological challenges many of which
have a direct effect on the quality of the multimedia experience.
For example, due to dynamically changing requirements and
networking conditions, the delivery of multimedia content
has traditionally adopted a best effort approach. However,
this approach has often led to the end-user perceived quality
of multimedia-based services being negatively affected. Yet
the quality of multimedia content is a vital issue for the
continued acceptance and proliferation of these services. Indeed,
end-users are becoming increasingly quality-aware in
their expectations of multimedia experience and demand an
ever-widening spectrum of rich multimedia-based services.},
keywords={Multimedia,Network},
pdf={advanced solution.pdf},
}
</bibtex>
<bibtex>
@article{244,
author={Seung-Bum Lee;Gabriel-Miro Muntean;Alan F. Smeaton},
title={Performance-aware Replication of Distributed Pre-recorded IPTV Content},
journal={IEEE Transactions on Broadcasting Special Issue},
year={2009},
pages={-},
volume={(in press)},
abstract={Video recording in IPTV systems is a promising service that provides time-shifted services in relation to storing TV content closer to user devices such as set-top boxes. Existing approaches do not support collaboration between nodes which have correlated contents, a fact that can affect the performance of the overall system. To make this service more interactive and proactive, this paper presents the architecture using the Smart Personal Information Network (Smart PIN) as a novel performance-based content sharing network for IPTV content which uses a user-centric utility-based Multimedia Data Replication Scheme (MDRS). This allows the exchange of data based on both network performance and user interest in exchanged multimedia content in order to achieve ef?cient content sharing. The proposed solution is evaluated through extensive simulations and results show much improved behaviour in comparison with two other existing general purpose data replicat on schemes.},
keywords={IPTV, Data replication, Content management, Peer-to-peer},
}
</bibtex>
<bibtex>
@article{253,
author={Bogdan Ciubotaru; Gabriel-Miro Muntean},
title={SASHA - A Quality-Oriented Handover Algorithm for Multimedia Content Delivery to Mobile Users},
journal={IEEE Transactions on Broadcasting Special Issue},
year={2009},
pages={-},
volume={(in press)},
abstract={The convergence of the existing network access technologies to a common IP-based architecture and the increase in popularity of accessing video content over the Internet makes IPTV a promising solution for media and entertainment industries. Additionally, video content delivery to the increasingly popular mobile devices over heterogeneous wireless networks makes IPTV even more appealing. However the distribution of multimedia content over heterogeneous wireless networks to mobile devices involves significant technical challenges related to mobility management and quality of service provisioning. The existing solutions do not consider quality of service as a decision making parameter for mobility management in general and handover management in particular.
This paper proposes the Smooth Adaptive Soft Handover Algorithm (SASHA), a novel quality-aware approach to handover based on load balancing among different networks using a comprehensive, Quality of Multimedia Streaming (QMS), function for decision making. SASHA represents the handover management solution at the core of the more comprehensive Multimedia Mobility Management System (M3S), a quality oriented mobility management framework for multimedia applications which maximizes user perceived quality by efficiently exploiting all available communication resources.
Simulation-based testing results are presented, outlining the performance of SASHA in different mobility scenarios. The evaluation is performed for different number of nodes performing handover simultaneous and for various situations in terms of networks’ overlapping area. The results shown indicate how SASHA outperforms other three mobility management solutions in terms of quality, scalability and resilience to the dynamics of the networks’ overlapping area.
},
keywords={Multimedia streaming, IPTV, Heterogeneous networks, Mobility, Handover},
pdf={Ciubotaru_Muntean_IPTV.pdf},
}
</bibtex>
<bibtex>
@article{338,
author={Fitzpatrick,J.;Murphy,S.;Atiauzzaman,M.;Murphy,J.},
title={Using Cross-Layer Metrics to Improve the Performance of End-to-End Handover Mechanisms},
journal={Computer Communication Preprint Online},
year={2009},
pages={13 Pages},
volume={10.1016},
abstract={Network centric handover solutions for all IP wireless networks usually require modifications to network
infrastructure which can stifle any potential rollout. This has led researchers to begin looking at alterna-
tive approaches. Endpoint centric handover solutions do not require network infrastructure modification,
thereby alleviating a large barrier to deployment. Current endpoint centric solutions capable of meeting
the delay requirements of Voice over Internet Protocol (VoIP) fail to consider the Quality of Service (QoS) that will be achieved after handoff. The main contribution of this paper is to demonstrate that QoS aware
handover mechanisms which do not require network support are possible. This work proposes a Stream
Control Transmission Protocol (SCTP) based handover solution for VoIP called Endpoint Centric Handover
(ECHO). ECHO incorporates cross-layer metrics and the ITU-T E-Model for voice quality assessment to
accurately estimate the QoS of candidate handover networks, thus facilitating a more intelligent handoff
decision. An experimental testbed was developed to analyse the performance of the ECHO scheme.
Results are presented showing both the accuracy of ECHO at estimating the QoS and that the addition
of the QoS capabilities significantly improves the handover decisions that are made.},
keywords={Echo,SCTP,VoIP,E-Model,Sigma},
pdf={using cross.pdf},
}
</bibtex>
<bibtex>
@article{339,
author={Qiao,Y.;Fallon,E.;Murphy,L.;Murphy,J.;Hanley,A.;Shi,Z.},
title={Transmission Scheduling for Multihomed Transport Protocols with Network Failure Tolerance},
journal={Telecommunication Systems Journal},
year={2009},
pages={10 pages},
volume={40},
abstract={In heterogeneous network environments, the
network connections of a multi-homed device may
have significant bandwidth differential. For a multihomed
transmission protocol designed for network
failure tolerance, such as SCTP, path selection
algorithms for data transmission drastically affect
performance. This article studies the effect of path
bandwidth differential on the performance of
retransmission strategies in multi-homing
environments. It identifies that fast retransmission on
an alternate path may cause receive buffer blocking
when path bandwidth differential is significant and the
receive buffer is limited. A theoretical model is
proposed for selecting retransmission path during the
fast retransmission phase, based on receive buffer and
path conditions. From these observations and analysis
results, this article proposes that path selection
strategies for transmitting new data and retransmitted
data should be decoupled. A new path selection
scheme is proposed and evaluated through SCTP
simulations.},
keywords={Multi-homing, Transmission Protocol, SCTP},
pdf={transmission.pdf},
}
</bibtex>
<bibtex>
@article{408,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={Open Corpus Architecture for Personalised Ubiquitous e-Learning},
journal={Personal & Ubiquitous Computing },
year={2009},
pages={197-205},
volume={13},
abstract={As the e-learning area matures, there are a growing number of e-learning content providers that produce and distribute material that covers a large range of topics, differs in quality and is represented in various formats. Lately, different devices and various network technologies allow extensive user access to educational content almost anywhere, anytime and from any device. Ubiquitous e-learning has the potential to provide continuous and context-based, educational material to human learners anytime, anywhere and on any device. Since each person has different expectations related to the content, the performance of the delivery and display of that content, it is desirable for an ubiquitous e-learning environment to provide user-oriented personalisation of e-learning material. However very often there are multiple sources of e-learning material at various web locations (open corpus resources) that cover the same topic, but differ in terms of quality, formatting and even cost. It is very difficult for learners to select the content that best suits their interests and goals, characteristics of the device used and delivery network as well as their cost budget. This paper proposes an innovative ubiquitous e-learning environment called Performance-based E-learning Adaptive Cost-efficient Open Corpus frameworK (PEACOCK) that provides support for the selection and distribution of personalised e-learning rich media content (e.g. multimedia, pictures, graphics and text) to e-learners such as it will best suit users’ interests and goals, meet their formatting preferences and cost constraints, while considering the limitations introduced by the end-user devices and the delivery networks to the user. PEACOCK’s main goal is to maximise the users’ e-learning experience and increase their learning satisfaction and learning outcome.
},
keywords={Adaptive e-learning systems - User-oriented personalisation - Cost-efficiency - Ubiquitous e-learning environment },
pdf={open corpus.pdf},
}
</bibtex>
<bibtex>
@article{456,
author={C.Xu;Gabriel-Miro Muntean;E.Fallon;A.Hanley},
title={Distributed Storage-Assisted Data-Driven Overlay Network for P2P VoD Services},
journal={IEEE Trans. on Broadcasting},
year={2009},
pages={1-10},
volume={55},
abstract={Providing VCR-like operations in Peer-to-Peer (P2P)
environments is a significant challenge. This paper proposes a distributed
Storage-assisted Data-driven overlay Network (SDNet)
to support P2P Video-on-Demand (VoD) services. It integrates
two networks: a Data-driven Overlay Network (DONet) and a
multi-way tree. DONet is enhanced and used for the routine video
distribution based on the buffer overlapping mechanism and
gossip protocol. A novel algorithm which uses a multi-way tree
structure and extra pre-fetching buffers at the nodes is proposed
to support efficient VoD operations. Videos are divided into uniform
segments, pre-fetched and stored in a distributed manner
along the tree topology. The cooperation between DONet-based
video delivery and the tree-located multimedia components enable
multimedia streaming interactive commands to be performed
efficiently. This paper presents and discusses the structure of
SDNet and the distributed storage scheme and details the cooperation
procedure. Simulation-based testing results show how the
proposed SDNet is an efficient interactive streaming solution in a
P2P environment.},
keywords={DONet, multi-way tree, P2P VoD, VCR-like.},
pdf={distributed.pdf},
}
</bibtex>
<bibtex>
@article{475,
author={Arturo Azcorra; Thomas Banniza; David Chieng; John Fitzpatrick; Dirk von-Hugo; Marek Natkaniec; Sebastian Robitzsch; Frank Zdarsky},
title={Supporting carrier grade services over wireless mesh networks: The approach of the European FP-7 STREP CARMEN [Very Large Projects]},
journal={IEEE Communications Magazine},
year={2009},
pages={14-16},
volume={47},
abstract={CARMEN is a three-year Specific Targeted Research Project (STREP) funded by the European Commission within the 7th Framework Program. The CARMEN access network will complement existing access technologies by exploiting low cost mesh networking techniques, thus minimizing deployment and maintenance costs. The CARMEN architecture introduces an abstraction layer that hides the specifics of the underlying access technology providing an abstract interface on top of which higher layers can be easily developed. This allows for the integration of current and future heterogeneous wireless technologies to provide scalable and efficient mobile ubiquitous Internet access, able to adapt to different environments and user requirements. Following these goals, CARMEN aims to define, study and implement link and technology abstractions, mobility support, and quality of service. The architecture also includes advanced monitoring features that allow for dynamic self-configuration, thereby reducing the installation and operational costs.},
keywords={CARMEN, Specific Targeted Research Project, carrier grade services, metropolitan areas, wireless mesh networks },
}
</bibtex>
<bibtex>
@article{484,
author={Frank A. Zdarksy, Sebastian Robitzsch, Albert Banchs},
title={Security Analysis of Wireless Mesh Backhauls for Mobile Networks},
journal={Journal of Network and Computer Applications},
year={2010},
pages={--},
volume={In Press},
abstract={Radio links are used to provide backhaul connectivity for base stations of mobile networks, in cases in which cable-based alternatives are not available and cannot be deployed in an economic or timely manner. While such wireless backhauls have been predominantly used in redundant tree and ring topologies in the past, mobile network operators have become increasingly interested in meshed topologies for carrier-grade wireless backhauls. However, wireless mesh backhauls are potentially more susceptible to security vulnerabilities, given that radio links are more exposed to tampering and given their higher system complexity.

This article extends prior security threat analyses of 3rd generation mobile network architectures for the case of wireless mesh backhauls. It presents a description of the security model for the considered architecture and provides a list of the basic assumptions, security objectives, assets to be protected and actors of the analysis. On this foundation, potential security threats are analyzed and discussed and then assessed for their corresponding risk. The result of this risk assessment is then used to define a set of security requirements. Finally, we give some recommendations for wireless mesh backhaul designs and implementations following these requirements.},
keywords={Security analysis, Wireless mesh backhauls, Mobile networks},
pdf={2010 - Zdarsky, Robitzsch, Banchs.pdf},
}
</bibtex>

Pubs:chapter

2012-03-09T13:07:28Z

Root: Created page with "<bibtex> @inbook{159, author={Moebs, S. and Weibelzahl, S.}, title={Blended Learning: Towards a Mix for SMEs - Stakeholders and their Priorities}, publisher={Blended Learning}, y..."

<bibtex>
@inbook{159,
author={Moebs, S. and Weibelzahl, S.},
title={Blended Learning: Towards a Mix for SMEs - Stakeholders and their Priorities},
publisher={Blended Learning},
year={2007},
pages={162-173},
abstract={While blended learning seems to be quite suitable for small and medium sized enterprises (SMEs), current uptake of this learning method is low. In this paper we propose a research design to examine the requirements for blended learning in SMEs. It is based on a three-round ranking-type Delphi study. Participants for the panels were carefully selected. Our method takes into account that the area and the term of blended learning are discussed in very different, partially contradicting connotations. For this purpose, we first provide the background of the initial research question and describe our research design. Next, we present preliminary results of the Delphi study and the steps in preparation of round 2. Participants were selected for the online-Delphi and grouped into panels of SME learners, trainers and providers of e-learning as well as learners from large companies as a control group for the SME learners.},
keywords={blended learning, SME, learning technology, Delphi study, Requirements},
pdf={wbl2007_BL4SMEs.pdf},
}
</bibtex>
<bibtex>
@inbook{457,
author={O.Ormond;Gabriel-Miro Muntean},
title={Dynamic Handover in Wireless LAN/MAN Heterogenous Networks},
publisher={Mobile WiMAX:Towards Broadband Wireless Metropolitan Area Networks},
year={2007},
abstract={In future generations of wireless networks, it is expected that different users with various multi-homed personal wireless devices will have the option of accessing their desired services via different available radio access networks. Given the variability of the radio environment properties and user mobility, the availability and characteristics of an access network will change in time and are highly dependent on location. As a result, dynamic reselection of the access network will be a necessary part of the mobility management mechanism (which
maintains the session connectivity as the user moves and/or the available access characteristics change). In their selection of a radio access network customers will consider cost and perceptive quality preferences for the current application and will rely on intelligent network selection decision strategies to aid or automate their choice.},
keywords={Wireless Network,Radio Network},
pdf={dynamic.pdf},
}
</bibtex>
<bibtex>
@inbook{458,
author={C.H.Muntean;Gabriel-Miro Muntean},
title={End User Quality of Experience Aware Personalised in E-Learning},
publisher={Architecture Solutions for E-Learning Systems},
year={2007},
abstract={In the context of new devices and with a variety of network technologies that allow access to the Internet, the providers of e-learning materials have to ensure that the users have a positive experience using their e-learning systems and they are happy to re-use them. Adaptive Hypermedia research aims to provide personalised educational material that ensures a positive learning experience for the end-users. However, user experience is dependent not only on the content served to them, but also on the user perceived performance of the e-learning system. This leads to a new dimension of individual differences between Web users: the end-user Quality of Experience (QoE). We have proposed a solution for Adaptive Hypermedia Systems (AHS) that provides satisfactory end-user QoE through the use of a new QoE layer. This layer attempts to take into account multiple factors affecting QoE in relation to the delivery of a wide range of Web components such as text, images, video, audio.
The effectiveness of our QoE layer has been tested in comparison to a standard educational AHS and the results of these tests are presented in this paper. Different educational-based evaluation techniques such as learner achievement analysis, learning performance assessment, usability survey and correlation analysis between individual student performance and judgment on system usability were applied in order to fully assess the performance of the proposed QoE layer. Results of the tests showed that the use of the QoE layer brought significant improvements in terms of user learning performance, system usability and user satisfaction with the personalised e-learning system while not affecting the user learning achievement
},
keywords={end-user QoE, adaptive hypermedia, e-learning, end-user perceived performance, learning performance },
pdf={end-user.doc},
}
</bibtex>
<bibtex>
@inbook{232,
author={Yang Yu; Vasken Genc; Sean Murphy; Liam Murphy},
title={Network Planning for IEEE 802.16j Relay Networks},
publisher={WiMAX Network Planning and Optimization },
year={2009},
abstract={In this chapter, a problem formulation for determining optimal node location for Base Stations (BSs) and Relay Stations (RSs) in relay-based 802.16 networks is developed. A number of techniques are proposed to solve the resulting Integer Programming (IP) problem - these are compared in terms of the time taken to find a solution and the quality of the solution obtained. Finally, there is some analysis of the impact of the ratio of Base Station (BS)/Relay Station (RS) costs on the solutions obtained. Three techniques are studied to solve the IP problem: (1) a standard branch and bound mechanism, (2) an approach in which state space reduction techniques are applied in advance of the branch and bound algorithm and (3) a clustering approach in which the problem is divided into a number of sub-problems which are solved separately, followed by a final overall optimisation step. These different approaches were used to solve the problem. The results show that the more basic approach can be used to solve problems for small metropolitan areas; the state space reduction technique reduces the time taken to ¯nd a solution by about 50%. Finally, the clustering approach can be used to find solutions of approximately equivalent quality in about 30% of the time required in the first case. After the scalability tests were performed, some rudimentary experiments were performed in which the ratio of BS/RS cost was varied. The initial results show that for the scenarios studied, reducing the RS costs results in more RSs in the solution, while also decreasing the power required to communicate from the mobile device to its closest infrastructure node (BS or RS).},
keywords={relay planning},
}
</bibtex>