Routing and wavelength assignment in optical WDM networks with maximum quantity of edge disjoint paths

In the present paper, routing and wavelength assignment (RWA) in optical WDM networks is discussed. Previous techniques based on the combination of integer linear programming based lpsolver and graph coloring are complex and require extensive use of heuristics such as rounding heuristic which makes them slow and sometimes practically not reasonable. Another method employs the greedy approach in graph theory for obtaining available edge disjoint paths. Even though it is fast, it produces a solution for any connection request which is far from the optimal utilization of wavelengths. We propose a novel algorithm, which is based on the maximum flow to have the maximum quantity of edge disjoint paths. Here, we compare the offered method with previous edge disjoint paths algorithms applied to the RWA. Comprehensive computer simulation shows that the proposed method outperforms previous ones significantly in terms of running time. Furthermore, the new method shows compatible or better performance comparing to others in number of wavelengths used.The earlier version was published in ICCS 2004, Poland (Krakow). This research was supported by the Ministry of Information and Communication, Korea under the Information Technology Research Center support program supervised by the Institute of Information Technology Assessment, IITA-2005-(C1090-0501-0019).