Route optimization for efficient failure recovery in optical burst switched networks

We consider the problem of offline route optimization for failure recovery in optical burst switched (OBS) networks. The primary and backup paths for each flow are determined in such a way to minimize the expected burst loss over normal and failure states. When a failure occurs, the affected traffic are transferred to the pre-configured backup path, resulting in fast recovery. Our route selection is efficient because we consider the unique features of OBS networks such as streamline effect. We argue that route selection based on Erlang B formula is not accurate because of this effect. We analyze the streamline effect and propose a more accurate loss estimation formula which takes the streamline effect into consideration. Based on this formula, we develop a mixed integer linear programming (MILP) formulation. Since the MILP-based solution is computationally intensive, we develop a heuristic algorithm. We verify the effectiveness of our algorithms through numerical results obtained by solving the MILP formulation with CPLEX and also through simulation results