High-speed management network for SONET-based network

The authors first define a SONET (synchronous optical network) management network model composed of three hierarchical domains; control area domain; site domain, and line domain. The authors focus on management network architectures necessary for establishing effective, real-time, and reliable operations support in such a domain structure, within the scope of CCITT TMN (telecommunication management network). They propose a hierarchical management network using the line and section DCCs (data communication channels). The line DCC is used for a high-speed internetworking between adjacent site domains, and the section DCC is for an internetworking between adjacent STE (section termination equipment). To avoid the long processing and handling delay incurred within a line domain, the frame relay protocol is used instead of a network layer routing function. For high-speed message handling in a site domain, a data link level relay is also proposed. For this purpose, a specialized network element is introduced, which performs a routing function on behalf of other network elements in a site