An Incrementally Scalable Multiprocessor Interconnection Network with Flexible Topology and Low-Cost Distributed Switching

Massively parallel computing architectures are becoming widely accepted in many computationally intensive areas. One of the prime advantages touted is their scalability, and yet while in principle a good degree of scalability is possible, in practice the unit of scaling is very coarse. The net effect of this is to make incremental expansion of such machines impractical except for large and expensive expansion to multiples of the original size and in some cases expansion by powers of two is required. In this paper a multiprocessor interconnection scheme with low fixed overheads and linear incremental scaling costs is described.