We study the design of logical survivable topologies for service protection against single or multiple failures in IP-over-WDM networks where protection can be offered at the optical layer or the electronic layer. Indeed, synergies need to be developed between IP and optical layers in order to reduce the costs and the energy consumption of the future networks.

We propose two new optimization models. The first one is an enhanced cutset model, relying on a column generation reformulation. The second one is a path model, based on a multi-flow formulation. Both models are highly scalable and allow the (near) exact solution of several benchmark instances, which were only solved with the help of heuristics so far. In addition, much larger instances than in previous studies can be solved as the proposed formulations avoids the explicit or implicit enumeration of cutsets. In the numerical experiments, we explore how survivability evolves when the number of logical links or the number of failure sets increase.

Dr. Jaumard is Professor and Concordia research Chair on the Optimization of Communication Networks.