Multi-wavelength multicast wavelength assignment algorithm for limited wavelength conversion in wavelength-division multiplexing networks

The multicast wavelength assignment problem in wavelength-routed wavelength-division multiplexing networks with limited wavelength conversions is addressed. A new multi-wavelength multicast wavelength assignment (MMWA) algorithm has been developed based on the multi-wavelength assignment strategy, by allowing multiple available wavelengths in a link to carry the multicast signal. This new multicast wavelength algorithm provides advantages for the network with limited wavelength conversions, by accommodating more multicast requests and providing good trade-off between wavelength cost and wavelength conversion cost. Simulation results show that the MMWA algorithm can satisfy more multicast requests in comparison with the previous single-wavelength assignment strategy. The improvement can be as high as 50-80%. This is highly significant. The MMWA algorithm also provides a good cost trade-off by making significant reduction of wavelength conversion cost (over 50%) while keeping the additional wavelength usage within a reasonable range (around 15%).