A fault-tolerant scheme for multicast communication protocols

Since the multicast communication is the best technology to provide one to many communication, more and more service providers are using this technology to deliver the same service to multiple customers. As such, providing fault tolerance to multicast connections is gaining attention both in business and research communities because a single link or a node failure in the multicast communication delivery tree will affect a large number of customers. There are some existing schemes proposed for fault recovery in the multicast communication. They either calculate a new tree without using any node from the existing tree or calculate a path from affected node/tree to the unaffected tree when a fault occurs. In either case, they need the global view of the multicast communication tree. In this paper, we propose a fault tolerant scheme in which we do not need the global view of the multicast tree. We compute the shortest path from a node to the source of the multicast tree assuming that the node's link to its parent node in the multicast tree is broken. The shortest path information is sent hop-by-hop toward the source and is stored in the routers. When the assumed broken link really breaks the recovery message is sent toward the source and the previously stored fault recovery message at each node is used to make a multicast recovery tree.