A Novel Algorithm for Constructing Light-Trees in Mesh WDM Networks

It has been recognized that light-trees should be as balanced as possible in order to guarantee an adequate signal quality and to scale to large destination sets, if power losses are taken into account when routing connections in mesh WDM networks. In this paper we study the problem of constructing such balanced light-trees. We propose a novel algorithm, called extended shortest path heuristic algorithm (ESPH) and is an extended version of the well known shortest path heuristic (SPH) algorithm, for the problem. The ESPH algorithm aims to minimize the difference between the optimal signal quality and the worst signal quality in the process of constructing light-trees. Simulations on a typical mesh network are conducted to verify the performance of the ESPH algorithm. Results demonstrate that the light-trees constructed by the ESPH algorithm are more balanced than those constructed by the only existing algorithm, called BLT (balanced light-tree algorithm) for the same problem, with a little more cost. Thus light-trees constructed by the ESPH algorithm can provide better signal quality and are more scalable than these constructed by the BLT algorithm