Toward optical packet-switched network architectures

In this paper we overview a generalized packet switching solution termed SDL (switched delay lines), which provides end-to-end `optical' bandwidth by maintaining the transmitted information in the optical domain. Compared to circuit switching, packet switching supports flexible sharing of bandwidth among a large number of users and diverse applications. To implement packet switching users need to be able to share various optical resources, such as wavelengths, switches, receivers and transmitters on packet transmission time scale. SDL provides these features, leading to optical packet switching, without the need for O/E and E/O conversions, or electronic buffering and processing of the data packets. It thus allows optical packet switched networks to be realized without the need to wait for the technological realization of optical processing devices to replace the relatively slow nodal electronic processing in existing networks. The design and operation of SDL are presented and demonstrated for a MAN system.