Multicast Communication in Multicomputer Networks Multicast Communication in Multicomputer Networks

EEcient routing of messages is the key to the performance of multicomputers. Mul-ticast communication refers to the delivery of the same message from a source node to an arbitrary number of destination nodes. While multicast communication is highly demanded in many applications, it is not directly supported by all existing multicom-puters; rather it is indirectly supported by multiple one-to-one or broadcast communications , which result in more network traac and a waste of system resources. In this paper, we study routing evaluation criteria for multicast communication under diierent communication paradigms. Multicast communication in multicomputers is formulated as a graph theoretical problem. Depending on the evaluation criteria and communication mechanisms, we study three optimal multicast communication problems, which are equivalent to the nding of the following three subgraphs: optimal multicast path, optimal multicast cycle, and minimal Steiner tree, where the interconnection of a mul-ticomputer deenes a host graph. We will show that all these optimization problems are NP-complete for the popular 2D-mesh and hypercube host graphs. Heuristic multicast algorithms for these routing problems are proposed.