The Concord algorithm for synchronization of networked multimedia streams

Abstract

Synchronizing different data streams from multiple sources simultaneously at a receiver is one of the basic problems involved in multimedia distributed systems. This requirement stems from the nature of packet based networks which can introduce end-to-end delays that vary both within and across streams. We present a new algorithm called Concord, which provides an integrated solution for these single and multiple stream synchronization problems. It is notable because it defines a single framework to deal with both problems, and operates under the influence of parameters which can be supplied by the application involved. In particular these parameters are used to allow a trade-off between the packet loss rates, total end-to-end delay and skew for each of the streams. For applications like conferencing this is used to reduce delay by determining the minimum buffer delay/size required.