MESH: distributed error recovery for multimedia streams in wide-area multicast networks

This paper addresses support for multi-party multimedia applications delivered across datagram wide-area networks such as the Internet. Our approach is to develop a novel retransmission protocol framework, MESH, that protects delay-sensitive multicast data streams against most network errors and delay variations. The MESH approach partitions the multicast group into subgroups, elects subgroup managers called active receivers, and localizes error recovery between active receivers. Novel features of our protocol include an explicit model for delay-sensitive retransmission, run-time evaluation at an active receiver to determine its retransmission partner, and the ability to handle multiple multicast data sources without building a per-source control framework. To evaluate the performance and network costs of MESH, a wide-area network simulation of digital video distribution is constructed and studied over a range of network loss rates. Simulation experiments show that both MESH and an alternative scheme, end-to-end forward error correction, provide excellent error control with MESH incurring significantly less network overhead