Optimal Layered Multicast Using Network Coding

We investigate the problem of constructing optimal layered multicast for heterogeneous sink nodes using network coding. Taking the flexibility of layered coding into account, we discuss the optimization problem that determines the optimal layers´ bit-rates for layered multicast, and express it into a mathematical formulation. Finding that this formulation is nonlinear and difficult to solve, we reduce it into several equivalent optimization problems and further propose a new optimization scheme. Different from the min-favorable algorithm in existing work, this new scheme is a global-favorable one, which determines the optimal layers´ bit-rates based on the max-flows of all sink nodes. Simulation results indicate that this new scheme could achieve the maximum of the aggregate throughput for layered multicast.