Circuit Establishment in an All-Optical Backbone Network

摘要

The evolution of optical networks can be compared to the evolution of electronic transmission systems. Technologies such as time division multiplexing (TDM), frequency division multiplexing (FDM), and code division multiplexing (CDM) are well established in electronic systems, and have an equivalent optical technology that is currently under development. Current optical-electrical-optical (OEO) systems utilize optical point-to-point links to provide extremely high data rates between connection points, and electronic switches for data routing. As key optical technologies become available, networks will migrate from OEO to an optimal optical-optical-optical (OOO) solution. The key optical technologies that help this migration are OOO switching and the multiplexing technologies in the optical domain such as wave division multiplexing (WDM) and optical-CDM. This article describes specific characteristics of optical technology and the requirements they place on routing and path selection. Moreover, a concept for an all-optical circuit-switched network is presented that utilizes near future WDM and optical-CDM technologies. In addition, we present a routing algorithm for all-optical networks that uses these technologies. This algorithm finds the best available circuit using a flooding mechanism based on link and switching impairments.