A Selective Retransmission Protocol for Multimedia on the Internet

A Selective Retransmission Protocol for Multimedia on the Internet


Mike Piecuch, Ken French, George Oprica, and Mark Claypool

In Proceedings of SPIE International Symposium on Multimedia Systems and Applications
(part of Photonics East - Information, Systems and Technology)
Boston, MA, USA
November 5-8, 2000


Internet multimedia applications have different requirements than do traditional text-based applications, placing new demands on TCP and UDP, the de-facto Internet transport protocols. We propose a Selective Retransmission Protocol (SRP) to balance the potentially high loss found in UDP with the potentially high latency found in TCP. SRP uses an application-specific decision algorithm to determine whether or not to ask for a retransmission for a lost packet, adjusting the loss and latency to the optimum level for the application. We develop and experimentally evaluate an audioconference using SRP on a wide-area network testbed. We find SRP outperforms both TCP and UDP in terms of multimedia application quality.