Routing Protocol Extension for Resilient GMPLS Multi-domain Networks

This paper evaluates the performance of multi-domain networks under the Generalized Multi-Protocol Label Switching control framework in case of a single inter-domain link failure. We propose and evaluate a routing protocol extension for the Border Gateway Protocol, which allows domains to obtain two Autonomous System disjoint paths and use them efficiently under failure conditions. Three main applications for the protocol extension are illustrated: reducing traffic loss on existing connections by exploiting pre-selected backup paths derived with our proposal, applying multi-domain restoration as survivability mechanism in case of single link failure, and employing proper failure notification mechanisms for routing of future connection requests under routing protocol re-convergence. Via simulations we illustrate the benefits of utilizing the proposed routing protocol extension for networks employing different resilient mechanisms (both protection and restoration), as well as for networks which have not employed any resiliency technique. We show the need for differentiated failure handling for improving network performance under failure situations. Furthermore, we draw parallel between different network parameters and the efficiency of the applied notification and survivability strategies in the network. Key–Words: multi-domain, GMPLS, BGP, AS-disjoint, performance enhancement