Optical Network Control: Architecture, Protocols, and Standards

8.6. Summary

In this chapter, we examined signaling for protection and restoration in mesh optical networks. The mesh architecture introduces certain new requirements for protection switching as compared with rings. Chief among these is the need for signaling mechanisms to notify failures and activate the protection path. In this regard, two broad choices for signaling were described: bit-oriented and message-based signaling. The bit-oriented method may have the advantage of speed and simplicity over the message-based method. It is, however, likely that the message-based method may be easier to deploy from an interoperability perspective. The performance of either signaling method in mesh networks is still an area of debate. In ring networks, ...