Joint routing and wavelength assignment in wavelength division multiplexing networks for permanent and reliable paths

In this paper, we tackle the routing and wavelength assignment problem for wavelength division multiplexing (WDM) networks containing permanent and reliable wavelength paths (WPs). It consists of finding the route and the wavelength of each WP for the normal state of the network and for the important failure scenarios. These scenarios might be the most probable failure scenarios or simply the failure scenarios of interest to the network planner (e.g., the single link failure scenarios). We propose a mathematical programming model for this problem. In order to find a solution within a reasonable amount of time, a simple heuristic algorithm is proposed. The results show that “good” solutions can be obtained with the proposed heuristic algorithm.