Joint multiple description coding and FEC for delay-constrained applications in congested networks

Multiple description coding (MDC) and forward error control (FEC) are two frequently used techniques for improving transport performance on lossy packet networks. Typically, these two techniques are used separately and independently with resulting performance dependent on network conditions, the choice of coding parameters and the applications being transported. In this paper we propose and analyze a joint MDC and FEC coding approach for delay-constrained applications on congested networks under some idealized modeling assumptions which are, nevertheless, sufficient to draw some qualitative conclusions. Specifically, for fixed delay constraints we show that under a range of operating parameters, there is an optimal FEC coding block size, channel coding rate and assignment of MDC rates which can achieve significantly improved end-to-end performance, compared to the performance achieved by using only MDC or FEC alone.