Resilient Routing Layers and Optical Burst Switching

Abstract – Two important challenges in Optical Burst Switching (OBS) are to reduce the packet loss and to achieve resilience in case of link or switch failure. In this report we build on a previously published method to increase resilience in IP networks, called Resilient Routing Layers (RRL). Based on RRL, we develop a new method that improves the burst loss probability and the resilience of OBS networks. We show how this new method provides loop free deflection routing in OBS networks in case of congestion. We have made a detailed discrete event simulation model of OBS networks and evaluated the performance of our new mechanism by simulating several realistic network topologies. The simulated traffic load is mainly Poisson distributed bursts, but also self similar IPtraffic is used. The paper also briefly indicates the difference in performance when so called different sets of RRL backup topologies are used