Routing and Wavelength Assignment in All Optical Networks Based on Clique Partitioning

Abstract

Wavelength Division Multiplexing (WDM) offers the capability to handle the increasing demand of network traffic in a manner that takes the advantage of already deployed optical fibers. A lightpath is an all optical communication path between end-to-end over a same wavelength used on each intermediate link. Wavelengths are the main resources in WDM optical networks. The wavelength assignment problem has been solved by mapping it to a heuristic based clique partitioning problem under the wavelength continuity constraint. For routing, Dijkstra's shortest-path algorithm is used. Here, we propose two new polynomial time heuristics for wavelength assignment called CPWA1 and CPWA2, based on clique partitioning concepts for static traffic demand with the objective of minimizing the number of wavelengths. The performance of our proposed algorithms are analyzed through extensive simulations on different set of traffic demands under a wide range of network topologies. The results show that proposed mechanism requires less number of wavelengths per fiber for a given set of traffic demand as compared to an existing well known algorithms.