Synchronous digital hierarchy network modeling

Due to the complexity of Synchronous Digital Hierarchy (SDH) networks, planning and developing such networks requires computer aided design tools. Because survivable SDH network design is a relatively new area and the need for planning tools has only been recognized in the last few years, virtually no comprehensive tools exist to address the specific questions which must be answered by SDH network engineers. In particular the migration of existing networks into SDH networks requires the capability to model existing transmission and switching methodologies while simultaneously modeling new hybrid topologies consisting of meshed point to point systems, unidirectional and bidirectional topologies and direct point to point TIE lines. Two hierarchical metropolitan optical transmission network architectures examined in this paper using a simulation tool to demonstrate the requirements for a SDH network analysis tool