A Novel Fast Multicast Algorithm with Enhanced Survivability in WDM Optical Networks

WDM optical networking technology is expected to facilitate bandwidth-intensive multicast application by establishing a “light-tree” which regards the source node as the root and all the destination nodes as the leaves. However, the existing multicast routing algorithms are time-consuming and the generated “light-trees” are very sensitive to failures, e.g., a single fiber cut can disrupt the information from transmitting to several terminals. In this paper, we propose a novel fast multicast algorithm with enhanced survivability (FMES), which applies a two-stage multicast routing approach, and employs a path protection scheme for each segment of the first stage tree. Analysis and experimental results show that FMES has the significant advantage of a much shorter running time than that in existing schemes, and this advantage can be enlarged in the distributed routing and signaling system of the coming intelligent optical networks. We also compare FMES with non-protection and full-protection schemes. It shows that the FMES scheme achieves the best trade-off between network survivability and resource-utilization. We illustrate our study with numerical experiments based on the real-life ChinaNet topology.