Surviving double-link failures for near optimal heuristic routing in protected optical networks

The survivability for double-link failures in WDM optical network has been studied in recent years. In previous algorithm, to survive the double-link failures each connection request will be assigned to one primary path and two link-disjoint backup paths. However, the previous algorithm is the so-called simple algorithm which may lead to low resources utilization and high blocking probability. In this paper, we propose a new heuristic algorithm called routing with optimal solution (ROS) to protect the double-link failures. Differing from the previous algorithm, ROS can obtain near optimal solution by recomputing the primary path and two backup paths based on the rerouting policy for each connection request. Simulation results show that ROS can significantly outperform the previous algorithm.