Cost Bounds of Multicast Light-Trees in WDM Networks
Multicast routing in WDM networks is to determine a set of light-paths on a physical topology from a source to a set of destinations involved in a multi-cast communication. The light-tree concept is introduced in to minimize the number of wavelength channels and transceivers used for a multicast session. Branching nodes in a light-tree should be equipped with light splitters. However, in sparse splitting WDM networks, there are two kinds of nodes: multicast capable nodes (MC, i.e., nodes equipped with light splitters) and multicast incapable nodes (MI, i.e. nodes without light splitters).