A “dual-tree” scheme for fault-tolerant multicast

To protect against possible network node or link failure and achieve high reliability of communications, pre-planned failure recovery schemes are needed in modern high-speed communication networks. A couple of schemes have been previously reported for multicast communications. We present a scheme based on a “dual-tree” structure in which a secondary tree for fault-tolerance purpose is built as a complement to a primary multicast tree. The secondary tree provides alternative delivery paths that can be activated when link or node failure is detected in the primary multicast tree. Simulation experiments show that this scheme has shorter restoration time and cause less multicast tree cost increase after restoration than some schemes proposed previously