Optimal Routing Based on Super Topology in Optical Parallel Interconnect

Traditionally the routing in optical parallel interconnect is based on an embedded virtual topology. However, one important fact that has been neglected in the past is that the wavelength assignment to transceivers actually creates additional (logical) links not present in the virtual topology. Such a side-effect can be utilized to significantly reduce the number of hops between a pair of processors. This observation leads to the concept of super topology. This paper considers the hypercube as the embedded virtual topology. The ideas contained here are easily applicable to optical parallel interconnects employing other virtual topologies as well. We present a general framework for embedding a regular topology, the structure of the super topology, the optimal routing algorithm, the distance between any pair of processors and the diameter in the super topology. 2001 Academic Press Key Words: WDM; optical parallel interconnect; routing; virtual topology; super topology; distance; diameter