Multicast Routing under Delay Constraint in WDM Network with Different Light Splitting

Abstract

Because the optical WDM network will become a real choice to build up backbone in the future, multicast communications on the WDM network should be supported in communication model for various network applications. In this paper, we define a new multicast problem that is routing a request with delay bound to all destinations in WDM network with different light splitting and propose a new formulation to solve the problem, where the different light splitting means that nodes in the network can transmit one copy or multiple copies to other nodes by using same wavelength. The new problem can be reduced to Minimal Steiner Tree Problem (MSTP) which belongs to NP-Complete problem, and can be solved by an efficient three-phase (Pre-Processing Phase, Generating Phase, and Refining Phase) solution model with Backward Stepwise Sub-path Replacing (BSSR) and Most Cost-Difference First Progressive Replacing (MCDFPR) heuristics to find a feasible light-forest in polynomial time. Finally, experimental results show that our solution model can obtain a near optimal solution.