A performance comparison between graph and hypergraph topologies for passive star WDM lightwave networks

Wavelength division multiplexing (WDM) allows the huge bandwidth of optical fiber to be divided into several high-speed channels in optical passive star based networks. For such processor networks, most of the proposed architectures for interconnecting nodes are based on graph topologies. Recently, topologies based on the hypergraph theory have emerged, motivated by the observation that each multiplexed channel can actually be seen as a logical resource shared among many processors, and not only between two of them. In this paper, we show that these hypergraph passive star WDM lightwave networks present many advantages with respect to graph-based ones, in terms of simulated packet delivery time, average number of hops, link utilization, and throughput. Furthermore, they use only a constant number of transceivers per node, and a sub-linear number of multiplexed channels.