Cross Layer Routing for Reliable Connections in IP over WDM Networks

In this paper, we study the routing scheme for reliable connections by using the concept of cross layer in IP/MPLS over WDM networks. In order to optimize the network resources utilization and to reduce the cost of optical-electrical-optical (o-e-o) conversions, an integrated hop and bandwidth routing algorithm, which considers shared risk link group (SRLG), load balance, and o-e-o conversions, is proposed in this paper. The basic idea of our scheme is to treat the routings of working paths and backup paths in different manners because each of them has its planned responsibility. As a working path is responsible for the conveyance of traffic most of the time, it is arranged to acquire a better transmission performance. And a backup path is arranged to take the advantage of resource sharing under the SRLG constraint. Our simulation results illustrate that the proposed scheme can properly arrange network resource in cross layer and the blocking rate is significantly reduced comparing with other schemes.