A distributed architecture for survivable SONET transport networks

The authors discuss today´s centralized bandwidth management network design. This is followed by a description of the distributed synchronous optical network (SONET) architecture. Today´s asynchronous network architecture is based on fixed centralized bandwidth management with a hierarchy of hubs targeted to keep system fill high. This architecture is highly vulnerable to transport system and hub failures. Crossconnects can be used to implement survivability, but with high cost, considerable planning effort, and poor restoration time performance. SONET rings permit a distributed network architecture which provides survivability without crossconnect disadvantages and hub vulnerability. A target distributed network is shown to have a 25% to 30% cost advantage over the hubbed network. Transition to this target can occur as SONET technology is introduced