The use of optical processing to perforin switch routing functions permits real-time routing of packets at high speed. The architecture of a 2 x 2 photonic packet switching node using optically processed fixed-directory routing, contention resolution (using deflection routing), and synchronization is presented. Deflection routing is well suited for contention resolution using processing technologies in which buffers are expensive or not available, as is presently the case with optical technology. Simplified optically processed self-routing procedures are found for banyan (baseline, shuffle-exchange, and crossover) and lattice networks. Although lattice networks require a larger number of switching elements than banyan networks, they have a simpler interconnection field, and unlike banyan networks, the self-routing rule for lattices can avoid any internal blocking. Two-dimensional (2-D) switching architectures are attractive for switch technologies which are readily fabricated in arrays, such as smart pixels. A 2-D architecture is easily derived by folding each column in the 1-D architecture, while preserving the interconnection field. The layout of a self-routing 2-D lattice, using 2×2 switches comprised of smart pixels, is described. Based on a “first-arrival” self-routing rule, no additional processing logic is required to perform routing.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics
- Electrical and Electronic Engineering