An Architecture for Differentiated Protection Against Single and Double Faults in GMPLS

In the context of an optical network GMPLS can be used to provide network robustness to faults through end-to-end path protection techniques. In this paper, we present a dynamic distributed model supporting five different classes of protection, including protection against single and double fault, with and without sharing of backup bandwidth. Beyond link and node failures we also consider protection against shared risk link group (SLRG) failure. In this paper, we briefly describe the protection model and the underlying algorithms for route selection and backup bandwidth sharing. After that we face the following issue: Which subset out of the five possible protection classes is convenient for an operator to support on the same network infrastructure? To answer this question it is fundamental to have a clear view of the trade-offs between the costs and the performances associated to each class. To achieve that we carried out an extensive performance analysis by means of simulations. For each protection class, we evaluated two fundamental performance metrics: the recovery probability under multiple faults, and the average per-demand resource usage. On the basis of such results, we are able to identify some basic guidelines driving the choice of the more convenient subset of protection classes to be implemented within a single network.