Multicast routing with mutual information accumulation

In this paper, we investigate the problem of multicast routing in networks using mutual information accumulation at the physical layer. In these networks, the minimum delay routing problem can be split into two subproblems: a) path selection, which is NP-complete, and b) resource allocation, which can be formulated as a linear program. We propose a simple, yet effective heuristic for path selection where we suggest that nodes are arranged, initially, in the order in which they decode a broadcast from the source. We compare the performance of this heuristic with other Steiner tree based heuristics for path selection using simulations and conclude that they exhibit similar delay performance. Additionally, good inner and outer bounds for multicast delay are derived and simulations show that our heuristic algorithms satisfy these bounds.