Minimising Perceived Latency in Audio-Conferencing Systems over Application-Level Multicast

  • Nick Blundell
  • Laurent Mathy
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3311)


In this paper, we propose a scalable and dynamically-adapting application-level multicast (ALM) routing protocol, designed specifically for audio-conferencing systems over the Internet.

Currently proposed ALM protocols try to optimise delay for the whole group of participating nodes during construction and maintenance of an overlay network which, when using standard packet flooding, can result in a number of the participants experiencing unacceptably-high latencies, unsuitable for real-time audio communication; whereas we propose to dynamically prioritise routing for those participants who are currently in conversation (i.e. those who require the lowest latencies in order to react to conversational cues) and allow higher latencies for participants who simply listen to the conversation without taking an active part in it in that particular moment in time.

Thus, we aim to provide low perceived latency for all of the audio-conference participants without any support from the underlying network.


Target Node Overlay Network Conversation Analysis Client Node Overlay Node 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Nick Blundell
    • 1
  • Laurent Mathy
    • 1
  1. 1.Lancaster UniversityUK

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