Abstract | This paper uses analysis and experiments to study the impact of var-ious congestion control algorithms and receiver buffering strategies
on the performance of streaming media delivery. While traditional
congestion avoidance schemes such as TCP’s additive-increase/-
multiplicativedecrease (AIMD) achieve high utilization, they also
cause large oscillations in transmission rates that degrade the smooth-
ness and perceptual quality of the video stream. We focus on un-
derstanding the interactions of a family of congestion control al-
gorithms that generalize AIMD, with buffer-based quality adapta-
tion algorithms for hierarchically-encoded and simulcast video. Our
work builds on and extends the results of Rejaie et al. [19]; we find
that the combination of a non-AIMD algorithm that has smaller os-
cillations than AIMD and a suitable receiver buffer allocation and
management strategy provides a good combination of low playout
delay and TCP-friendly congestion control. The paper describes
these mechanisms and the results of experiments conducted using
a prototype video server for MPEG-4 video, showing that our ap-
proach can improve the interactivity and adaptivity of Internet video.
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