A Cost Efficient Multicast Routing and Wavelength Assignment in WDM Mesh Network

Abstract

Multicast Routing and Wavelength Assignment (MRWA) is a technique implemented in WDM optical networks, where dedicated paths are established between a source and a set of destinations, unlike unicasting where a source is connected with only one destination. For a multicast session request a multicast tree is generated to establish a connection from source to all the destinations. A wavelength is assigned to each and every branches of the generated multicast tree to create a light-tree for the session. In this work, we have tried to minimize the wavelength usage to establish multicast sessions for a set of multicast session requests. Our approach is to minimize the size of the multicast tree by sharing branches, as much as possible, to connect all the destinations from the source node. A lesser usage of links minimizes the collision probability for the assignment of wavelength, say w, in each of the selected links to be assigned the wavelength. Secondly, greater sharing implies lesser splitting. As splitters are costly, minimum usage of splitters incurs lesser infrastructure cost in the network. The effectiveness of our approach has been established through extensive simulation on different set of multicast session under different network topologies and comparing with standard Minimal Spanning Tree (MST) based algorithm. The simulation shows our algorithm performs better than the MST based algorithm.KeywordsWavelength Division Multiplexing (WDM)Light-treeSplittingMulticast Routing and Wavelength Assignment (MRWA)Multicast Session