Self-routing crossbar packet switch employing free-space optics for chip-to-chip interconnections

Abstract

A nonblocking crossbar network that employs free-space optical interconnections between optoelectronic switching nodes is proposed. The architecture can be implemented using standard electronic technologies for the switching logic, systematic self-electro-optic effect devices for modulators and detectors, and fairly simple optics to connect adjacent chips in the network. Since optical interconnections are only required between adjacent chips, this architecture may have advantages compared with other architectures that have been proposed using optical interconnections between electronic chips. In addition, a simple routing scheme is discussed that permits the optical crossbar network to be operated as a self-routing packet switch. This packet switch provides for contention resolution, priority routing, and automatic increases in the priority of blocked packets. An example illustrating one implementation of the network is then described and analyzed.