A hierarchical extension to RSVP-TE for fast lightpath setup in dynamic optical networks

Abstract

A dynamic optical network with a fast resource allocation ability is proposed to satisfy the increasing requirement of the fast developing services. The lightpath setup delay of the traditional serial signaling distribution method used by RSVP-TE and CR-LDP increases linearly with increasing scale of the network. When the network size becomes too large, the signaling delay may cause problems to real-time services and fast recovery. So, we propose a combined hierarchical signaling distribution (CHSD) method for fast lightpath setup and an extended RSVP-TE to support a hierarchical signaling distribution process. The simulation and theoretical analysis show that the lightpath setup delay by CHSD is reduced from O(N), which is the delay of the traditional serial distribution method, to $O(\sqrt[p]{N})$ in the best condition. The delay is also related to the hierarchical structure of the network and when the scale of the routing areas (RA) takes a uniform distribution and the RA number equals to $\sqrt[p]{N}$, a minimum distribution delay is achieved. Thereafter, we extend RSVP-TE to support this hierarchical distribution method. By the simulation result, the extension is proved to be feasible.