All-optical multicast routing in sparse splitting WDM networks

This paper studies all-optical multicast routing in wavelength-routed optical networks with sparse light splitting. In a sparse splitting network, only a small percentage of nodes is capable of light splitting, i.e., multicast capable, and most of the nodes are multicast incapable. The typical approach to this problem is combining an existing Steiner tree heuristics with some rerouting procedure to refine the trees. Therefore, the cost in terms of the total number of wavelengths used for all tree links (referred to as wavelength channel cost) is very high. In this paper, we propose a new mechanism that constructs light-trees for sparse splitting optical networks without additional rerouting. We design two efficient schemes to build a light-tree for any given multicast session. We then extend our mechanism to support dynamic group membership. The simulation results show that our mechanism can build light-trees with the least wavelength channel cost and with the smallest number of wavelengths used per link.