CENTRE DE RECHERCHE INSTITUT DES SCIENCES DE L’INGÉNIEUR Rapport de recherche CR-ISCI-2006-1 Dynamic Routing for Shared Path Protection in Multi-domain Optical Mesh Networks D.L.Truong

The routing problem for shared path protection in multi-domain optical mesh networks is more difficult than that in single-domain mesh networks due to the lack of complete and global knowledge on the network topology and bandwidth allocation. To overcome this difficulty, we propose an aggregated network modeling by underestimation with a two-step routing strategy. In the first step, a rough routing solution is sketched in a virtual network which is the topology aggregation of the multi-domain network. A complete routing is then determined by solving routing problems within the original single-domain networks. The first step can be solved by either using an exact mathematical programming or an heuristic while the second step is always solved by heuristics. Computational results show the relevance of the aggregated network modeling. They also prove the scalability of the proposed routing for multi-domain networks and its efficiency in comparison with the optimal solution obtained by using the complete information scenario. In addition, we believe that short working paths lead to a higher possibility of sharing backup resources between backup path. Our mathematical programming model minimizes the total requested resource and at the same time provides a short working path resulting a further overall resource saving.