REDUCING COMMUNICATION LATENCY WITH PATH MULTIPLEXING IN OPTICALLY INTERCONNECTED MULTIPROCESSOR SYSTEMS

Reducing communication latency, which is a performance bottleneck in o ptically interconnected multiprocessor systems, is of prominent import ance. A conventional approach for establishing connections in multiple xed networks uses a set of independent time slots (or virtual channels ) along a path for each connection. This approach requires the use of switching devices capable of interchanging time slots, and thus introd uces latency in addition to hardware and control complexity. In this p aper, we propose an approach to all-optical Time Division Multiplexed (TDM) communications in multiprocessor systems. The idea is to establi sh a connection along a path using a set of time slots (or virtual cha nnels) that are dependent on each other, so that no time-slot intercha nging is required. We compare the proposed approach with the conventio nal one in terms of the overall communication latency. We found that, despite the possibility that establishing a connection may take a long er time, the proposed approach will result in lower overall communicat ion latency as it eliminates the delays introduced by the time-slot in terchanging switching devices.