Routing and wavelength assignment in WDM network using IWD based algorithm

In this paper, we consider the Routing and Wavelength Assignment problem in WDM optical networks. We consider the dynamic traffic and assume that in each optical fiber the number of wavelengths has fixed. In this paper, our attempt is to minimize the call connection blocking ratio using Intelligent Water Drops (IWD) Algorithm for RWA problem in an optical network. The IWD algorithm employed has modified to take into consideration the congestion and length information during the routing decision process for the optimal routes of primary lightpath establishments. Inspired by natural water drops principles, we propose a modified IWD algorithm for RWA problem in the dynamic WDM networks with improved blocking performance. Simulation results show that IWD based RWA problem can significantly achieve a lower blocking ratio performance than the traditional routing strategies.