Scheduling Based on Minimal Conversion Degree With Respect to Wavelength Conversion and Coding in Optical Multicast Node

Optical multicast collision occurs more frequently for the replication and forwarding of optical multicast increase in the switch node. In this letter, an optical multicast switching node architecture configured with wavelength conversion and network coding is proposed. The proposed node architecture uses a group of output shared wavelength converters in the wavelength domain and a group of feedback shared encoders to resolve the optical multicast collision. To minimize the total conversion degree, we propose an improved algorithm, maximal weighted stable set, to assign wavelength converter with respect to the wavelength conversion degree as the weight. Concretely, the graph coloring matching algorithm is used to select the wavelength converter with minimal wavelength conversion degrees. Compared with the node architecture with two layers wavelength conversion and with full range wavelength conversion, analyses and simulation results show that the proposed node architecture largely reduces the packet loss probability with low cost of wavelength conversion and results in a better performance to solve multicast collision.