IP-over-WDM Control and Signaling

The optical layer is evolving to be a fully-functional optical network that supports on-demand bandwidth provisioning. In this evolution, the network control and signaling is essential to address the critical challenge of the lightpath provisioning in real-time and the network survivability. This chapter first briefly introduces the network control in two different directions rooted from the telecommunication and Internet. Due to the consensus that the IP traffic will dominate in the future data networks, this chapter focuses on the IP-centric control and signaling. The MPLS control plane and its extensions to optical networks, called MPλS/GMPLS, are discussed in detail regarding the functional requirements and the issues raised by the optical network. Two families of IP signaling protocols, LDP/CR-LDP/CR-LDP GMPLS extension, and RSVP/RSVP-TE/RSVP-TE GMPLS extension, have been introduced and examples have been given to illustrate the LSP/lightpath setup. Finally, the optical internetworking and signaling across the optical network boundary are examined, and a sample control plane is presented.