Optical Interconnects for Multiprocessors Cost Performance Trade-offs

Fiber optic interconnects baaed on wavelength division multiplezing (WDM) are a promising candidate for future interconnection networks due to their high bandwidth, low wire density and their low power requirements. As the cost of optical communication hardware for WDM star baaed interconnects may be large, we introduce reduced cost structures. The performance of the optical implementations of the reduced cost structures is compared to the electronic implementations for the hypercube topology. The performance is compared in terma of the communication overhead in implementing two commonly used algor i t h m on these structures. Our results indicate that in most situations, the optically implemented reduced cost variations perform better than the electronic amplementatwns. Moreover, the hardware cost-performance trade-ofls show that among the optically implemented schemes, the performance degmdation of the reduced cost variations is not significant in view of the hardware savings involved.