IP multicast over WDM networks

Abstract

We consider multicast over wavelength-routed networks. To overcome the drawbacks of previous works, an expanded-graph model is developed to transform a WDM network into a graph, and then apply existing Graph Theory algorithms on the graph. The expanded-graph model simplifies the resulted graph significantly, compared with other models. To further reduce the computational complexity, while maintaining certain level of quality of solution, we have developed a layered-routing approach. The approach corresponds to the multi-layer nature of WDM network. To facilitate algorithm development, two generic algorithm frameworks are proposed. In addition, we have developed two analytical models for adaptive unicast routing and fixed multicast routing, respectively. The two models are both based on queueing network theory. One distinct feature is that both models take limited capabilities into consideration. Finally, we also consider delay-constrained multicast over WDM network. We anticipate the need for QoS routing in future in fast-speed WDM networks.