A novel contention resolution scheme based on network coding for optical multicast node

Optical buffering using fiber delay lines (FDLs) has been proved to be the best choice to resolve contention for optical packet switching node. Due to the absence of optical RAM, XOR network coding becomes a new packet contention resolution technology in the all-optical networks. In this paper, we present an all-optical node architecture configured with a primary network coding module and a supplementary FDL buffer module for contention resolution. The contending packet is resolved by output shared XOR network coding module firstly without any time delay. The feedback shared FDL buffer is used to resolve the still packet contention after NC module, which is constructed by a FDL buffer loop group. Moreover, the minimum length-cascaded buffer scheduling technique (MLCBST) is designed to schedule the contending packet to available output with minimal transmission delay. The simulation results show that the proposed architecture and the MLCBST have an obvious effect on reducing the packet loss probability and decreasing the average delay for optical packet switching node.