On-the-fly coding for real-time applications

ABSTRACT

Although ironically it does not offer any real-time guarantee, Internet is a popular solution to support multimedia time-constrained applications (e.g. VoIP, Video Conferencing, ...).

Following this trend, this paper focuses on the performance of these applications by studying the benefit of using a novel reliability concept which aims at significantly improving the performance of these time constrained applications over lossy best-effort networks.

This reliability mechanism emerged from several recent works from both network and coding theories. Its principle is to integrate feedbacks in an on-the fly coding scheme in order to optimize the trade-off "packet decoding delay" vs "throughput". We present the first evaluations of this mechanism for VoIP and video-conferencing applications for various erasure channels. Compared to classic block-based erasure codes, the results show significant gains in terms of quality observed by the user for both applications.

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INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.2 Network Protocols

General Terms:
Algorithms, Design

Keywords:
VoIP, erasure code, reliability, video-conferencing