Adaptive hybrid error control for IP-based continuous media multicast services

Abstract

To overcome IP packet loss for continuous media applications, efficient error control mechanisms are required that take into account real-time constraints while trading off additional bandwidth and application level service quality. For multicast error control, heterogeneity caused by different receiver loss resiliency characteristics must be addressed as well. Related work has shown the advantages of hybrid error control that combines Forward Error Correction (FEC) with retransmission of parity packets (ARQ). We present a novel scheme for dynamically adapting hybrid error control to changing network conditions that minimizes the impact of packet loss on the received media quality. For the adjustment of the appropriate amount of redundancy an optimization mechanism using a set of equations which reflect network and media characteristics is applied. Analytical and simulation results are presented demonstrating the usefulness of the new scheme.