Overviews the technologies being developed and deployed for the third generation of digital carrier transport networks. Without getting highly technical, the author examines the role of optical fiber and optical routers in these networks, with an emphasis on wave division multiplexing, and describes multiprotocol label switching and new multiplexing hierarchies. The introductory chapters review the characteristics of optical fiber and second generation technology implemented as SONET and SDH. Annotation c. Book News, Inc., Portland, OR (booknews.com)