Design Strategies for Meeting Unavailability Targets Using Dedicated Protection in DWDM Networks

Service providers operating dense-wavelength-division-multiplexed networks are often faced with the problem of designing their networks such that a certain level of service availability can be delivered to their customers. This paper introduces optimization-based algorithms that address this problem efficiently and effectively. For a given network topology, specified by existing dark-fiber links, our algorithms determine a cost-effective solution consisting of the size and location of equipment needed to satisfy the desired amount of point-to-point traffic demands. In addition, the solution approach discussed in this paper delivers estimates for the service unavailability probability of each traffic-demand pair and enables the service provider to programmatically determine which and how many supplemental node-disjoint protection paths are required in order to attain a prespecified demand-pair unavailability target. To the best of our knowledge, these algorithms provide the user with the most detailed design created by any optimization-based design tool to date. The efficiency and effectiveness of the proposed network-design algorithms is studied using an empirical analysis