SONET SYSTEM FOR NORTH-AMERICA

In 1988, the Phase I standard of Synchronous Optical Network (SONET) was established by ANSI. Standards committees are planning for Phase II, which defines the functions for maintenance and operations, and which will be generally standardized in late 1990. Fujitsu produced the Fiber Loop Multiplexer (FLM) series conforming to the Phase I standard for the Regional Bell Operating Companies (RBOCs) before its competitors. The FLM was well received. This paper describes the SONET systems created by Fujitsu, Fujitsu's plan to upgrade to Phase II, and the key technologies used in the product.