Routing in a MPLS network featuring preemption mechanisms

In the context of multiprotocol label switching (MPLS), we propose an integration of a computationally efficient preemption mechanism into a very dynamic label switched paths (LSPs) routing scheme we described previously (Blanchy et al., http://run.montefiore.ulg.ac.be//spl sim/blanchy, 2002). This preemption scheme includes a quick heuristic able to select the most interesting LSPs to reroute from a link. The efficiency of this algorithm is obtained through a very rigid, but seemingly appropriate, policy which is concerned which LSPs are appropriate for preemption. A feedback from preemption on the routing process is proposed, in order to regulate the rate of rerouting and to tune the balance between stability and continuous reorganization in a network. This integrated traffic engineering entity is tested on the accuracy of the heuristic, the relevance of the feedback and the whole integration, the influence of the routing policy on the preemption mechanism and the reliability of the managed network.