Spare capacity allocation in multi-layer networks

In this paper, we consider the problem of provisioning spare capacity in multi-layer backbone networks in order to meet survivability requirements. A matrix based model is presented showing how failure propagation can be mapped across network layers. Two different multilayer spare capacity allocation optimization problems are formulated utilizing the failure propagation matrix to determine the location and amount of spare capacity in each network layer. In order to scale the models a fast and efficient approximation algorithm based on our early successive survivable routing (SSR) technique is developed. Numerical results for a variety of networks show that near optimal solutions are found by the proposed heuristic algorithm.