An expanded graph model for MCRWA problem in WDM networks

The future multimedia applications demand large bandwidth and require efficient multicast for economic use of network resources. The wavelength division multiplexing (WDM) networks have emerged as a promising technology to support high bandwidth demands. This paper proposes an expanded graph model to handle the multicast routing and wavelength assignment (MCRWA) problem in WDM optical networks. In the model, the WDM network is transformed into a graph. Application of graph theory algorithm will enable the routing and wavelength assignment to be done in a single step. The model is of general nature and is applicable to all kinds of WDM networks. We apply a degree-constrained SPH heuristic as an example to solve the MCRWA problem in a general WDM network that possesses finite light splitting and wavelength conversion capabilities. The simulation results show the broking performance of the optical networks under various constraints.