A Differential Evolution with Pareto Tournaments for solving the Routing and Wavelength Assignment problem in WDM networks

The technology based on Wavelength Division Multiplexing (WDM) applied to optical networks has resolved the bandwidth waste in this kind of networks. WDM divides the bandwidth of an optical fiber in different wavelengths that can be used by electronic devices to send and receive data without bottlenecks. Another problem appears when the necessity of choice of the path and the wavelengths to interconnect a set of source-destination pairs comes up. This problem is known as Routing and Wavelength Assignment (RWA) and there are two types, depending on the demands: Static-RWA and Dynamic-RWA. In this paper we present a multiobjective evolutionary algorithm to solve this problem. We choose the Differential Evolution (DE), incorporating the concept of Pareto Tournament (DEPT). To determine the parameters of the algorithm, we used two real different topologies (the first is a topology from USA, NSF network; and the second is a topology from Japan, NTT network) and six sets of source-destination pairs for each topology, that is, a total of twelve instances. After all experiments, we can conclude that with this multiobjective evolutionary algorithm, we have obtained better results than the other approaches published in the literature.