Three types of problems of the overall mapping problem are addressed: graph embedding to realize the mapping, the use of the most efficient methods to decrease the influence of the communication, and the study of the properties of interconnection network. These three topics are investigated theoretically and experimentally. The study of embedding is concentrated on multi-dimensional grids, De-Bruijn networks and other fixed degree networks. Communications will be studied under different models, for instance the store-and-forward mode or the circuit-switched mode. Fault-tolerant communication protocols using different faults model are investigated. The complexity of the graph embedding and the communication problem highlights the importance of the underlying network. A network should be of low degree, high regularity, high connectivity and of good extentability. Constructions for networks based on Cayley graphs or compound techniques will be studied. The properties of the important class of multistage networks will be investigated.
The existence of disjoint Hamiltonian cycles embedding the binary trees into various networks like toroidal grids in de Bruijn networks was established. A library of mapping algorithms was implemented and integrated into the commercial Parix operating system of Parsytec Computer, Aachen, Germany. Lower and upper bounds on broadcasting in various networks like de Bruijn and shuffle exchange were given. Systolic algorithms for broadcasting, accumulation and gossiping have been developed for various networks. Construction of a family of dense bus networks of diameter 2 has been done. An architectural principle which combines the good properties of multistage networks in terms of communication throughput and latency with the cost efficient realization of mesh networks has been developed. The communication throughput of multistage interconnection networks was investigated using theoretical methods.
Funding SchemeCSC - Cost-sharing contracts
SO17 1BJ Southampton