Interprocessor communication, parallel algorithms

In general, the topology of interprocessor communication reflects both the structure of the mathematical algorithms being employed and the way that the wave packet is distributed. For example, our very first implementation of parallel algorithms in a study of planar OH - - CO [47] used fast Fourier transforms (FFTs) to compute the action of 7, which also required all-to-all communication but in a topology that is very different from the simple ring-like structure shown in Fig. 5. 

Parallel machines. Interprocessor communication becomes the problem to solve (for algorithms that won t fit on a single processor, this assumes that the algorithm can be decomposed for multiple processors and intermediate results can be communicated between cooperating processors). 

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