Pipelined communications on optical busses

The architecture of Array Processors with Pipelined Busses (APPB) has recently been proposed as a new hybrid optical-electronic parallel computer architecture which uses messagepipelined optical busses for interprocessor communications. In this paper we show how pipelined messages can be interleaved and overlapped so that the communication capacity of a pipelined optical bus is fully utilized. We also show how to align communicating processors in twodimensional APPB so that only one bus cycle is needed for routing messages between any two communicating processors in a given communication structure. Finally a comparison of the cornmunication bandwidth of a pipelined bus with that of an exclusive access bus is given which shows that the pipelined bus achieves an asymptotically linear in number of processors on the bus improvement over the exclusive access bus.