Issues on diverse routing for WDM mesh networks with survivability

The task of finding a physically disjoint protection path from a working path to guarantee a service continuity during the occurrence of failures has been one of the most important issues for improving survivability of the optical Internet. In this paper, we focus on the study of finding asymmetrically weighted optimal node-disjoint path-pairs for shared protection so that network performance in terms of success rate of building up disjoint path-pairs and average restoration time are improved. We first propose and examine a novel heuristic algorithm to solve the diverse routing problem in a network with heterogeneous link states for working and protection path pairs, which is based on the Sub-Optimal Path-Solver (SOPS), a new method for finding loop-less K-shortest paths. Then a simulation-based study on the weighting parameter of working paths versus network performance is conducted.