Comparative performance of circuit-switched networks based on blocking probability

A class of dynamic parallel processor interconnection networks, called circuit-switched networks, are composed of layers of small crossbar elements. Although such networks provide full connectivity, they are often called blocking networks, since contentions for network links sometimes block message pathways. The results from a study are reported in which the goal was to determine the effect of variations in a network´s topology to aid in the selection of more optimal architectures. Three approaches were used in the study to determine the relative blocking performance of networks based on topology. Several popular topologies were analyzed by these approaches with respect to availability and probability of blocking. A discussion of the results provides insight into the design of networks containing large numbers of computer nodes by showing why some types of topologies produce more efficient networks than do others.