Date Added: Nov 2012
Intra-session network coding has been shown to offer significant gains in terms of achievable throughput and delay in settings where one source multicasts data to several clients. In this paper, the authors consider a more general scenario where multiple sources transmit data to sets of clients and study the benefits of inter-session network coding, when network nodes have the opportunity to combine packets from different sources. In particular, they propose a novel framework for optimal rate allocation in inter-session network coding systems. They formulate the problem as the minimization of the average decoding delay in the client population and solve it with a gradient-based stochastic algorithm.