Survivable Routing with Path Length Constraint in WDM Networks

Wavelength-routed WDM optical network has the tremendous capability of providing overgrowing needs of higher bandwidth to the end users. It uses preconfigured optimal lightpaths to carry the traffic of users from one node to another node. Hence, an intelligent RWA algorithms required to be employed to achieve better performance of the network. In this paper, we investigate the impact of path lengths in the RWA problem. We study the effect of length of the path in the blocking performance of network when working and protection paths computed for the resiliency to an occurrence of single link failure in WDM network. Proposed algorithms will optimize individual connection request. In this work, we have simulated and analyzed the relative performances of the three RWA heuristics algorithms for survivable routing and wavelength assignment problem named as Shortest Path Pair (SPP), Shortest Longest Path Pair (SLPP) and Longest Shortest Path Pair (LSPP) strategy. These algorithms have been compared based on the percentage of successful lightpaths established. The proposed heuristic strategies described here differs from each other in the length of the path of working and backup path. The simulation results reveal that SPP algorithm always outperforms in terms of call blocking performance ratio. Hence, for better network performance survivable RWA algorithm ensure to consider a pair of the shortest path as a working and protection path.