A multicast routing protocol for network coding

This paper proposes a network-coding-based multicast routing protocol(NCMRP) at IP layer for wired networks. The basic idea of NCMRP is that the source broadcasts routing packets to find multiple paths from the source to each sink, and the multicast topology is constructed with the multiple paths. NCMRP brings network coding into multicast with a few minor changes to the protocol packet formats of distance vector multicast routing protocol(DVMRP) and is compatible with it. We implemented a prototype network system based on NCMRP and sparse linear network coding. With the prototype system, video files are multicasted to evaluate the practicality of NCMRP. The experimental results show that NCMRP takes about 2 times of DVMRP´s time to construct a multicast topology, which is reasonable for practical implementation. NCMRP achieves a throughput several times of DVMRP´s while only with 30% extra bandwidth consumption.