Enhanced scaling and performance of an optical interconnect based on wavelength-division-multiplexed clockwork routing

Abstract

An optical routing network for applications requiring large numbers of nodes and low latency, such as the interconnection network inside a future high-end supercomputer, is described. The network is a development of an existing architecture based on a combination of clockwork routing and wavelength division multiplexing (WDM-CR). Although using the same underlying photonic technologies as WDM-CR, the new architecture has several advantages, including the following: the network can be scaled to greater numbers of nodes; routing between closely located nodes is more direct, resulting in lower latency and higher overall throughput; arbitration and control mechanisms are simplified; and the need for optical amplification is removed. Results obtained from full discrete-event traffic simulations demonstrate scalability to interconnection networks as large as 4096 nodes in a flat architecture.