Progress in standardization of SONET

The development of a specification for a standardized optical interface, the synchronous optical network (SONET), is described. The initial project goals, most of which were accomplished with the release of the initial SONET specifications, ANSI T1.105-1988 and ANSI T1.106-1988, are discussed. ANSI T1.105-1988 contains specifications for the rate and format of the SONET interface. ANSI T1.106-1988 contains the optical parameter specification needed to complete the interface specification. Differences between the SONET standard and other interface specifications are examined. The CCITT standardization effort and its relationship to SONET are considered. The second and current phase of SONET, namely, the development of a standard for communicating operations support information across the data communications channel, is described. Related standards activities are summarized, and plans for future SONET standards are outlined. The likely network impact of the planned evolution of the SONET standard over a number of years is assessed.<>