Expanded Delta Networks for Very Large Parallel Computers

We analyze a generalization of the traditional delta network, dubbed Expanded Delta Network (EDN), which provides multiple paths that can be exploited to reduce contention. In massively parallel SIMD computers, the trend is to put a large number of processors on a chip, but due to I/O constraints only a subset of the processors may have access to the network at any time. This leads to the Restricted Access Expanded Delta Network of which the MasPar MP-1 router network is an example.