A dual-hamiltonian-path-based multicasting strategy for wormhole-routed star graph interconnection networks

Multicast is an important collective communication operation on multicomputer systems, in which the same message is delivered from a source node to an arbitrary number of destination nodes. The star graph interconnection network has been recognized as an attractive alternative to the popular hypercube network. In this paper, we first address a dual-hamiltonian-path-based (DHPB) routing model with two virtual channels based on two hamiltonian paths and a network partitioning strategy for wormholerouted star graph networks. Then, we propose three efficient multicast routing schemes on basis of such a model. All of the three proposed schemes are proved deadlock-free. The first scheme, networkselection-based dual-path routing, selects subnetworks that are constructed either by the first hamiltonian path or by the second hamiltonian path for dual-path routing. The second one, optimum dualpath routing, selects subnetworks with optimum routing path for dual-path routing. The third scheme, two-phase optimum dual-path routing, includes two phases, source-to-relay and relay-to-destination. Finally, experimental results are given to show our proposed three routing schemes outperform the unicast-based, the hamiltonian-path, and the single-hamiltonian-path-based (SHPB) dual-path routing schemes significantly.