Optical Switching in Coherent Lightwave Systems

Abstract

Broad-band networks providing various kinds of services, such as video and high — speed data communications, have received increasing attention in not only local-area networks(LANs) but also wide-area networks(WANs). The possible architecture of a global WAN is illustrated in fig.1. With such a network, broadband communication/distribution services may be offered all over the globe. Optical communications utilizing both inland and under-sea optical fiber transmissions, together with satellite communication, will play an important role in broad-band global WANs. Recent progress in optical fiber transmission has already made worldwide point-to-point transmission links possible. Coherent transmission technology would further enhance transmission length and information capacity. Optical switchihg would be a key technology for achieving all-optical broad-band WANs, where switching and routing functions,as well as transmission, will be accomplished in optical domain.