A high-speed protection scheme for multiple-priority-class traffic in WDM ring networks

We propose a high-speed protection scheme for multiple-priority-class traffic in WDM ring networks. The proposed scheme achieves high-speed protection with a rapid suspension procedure for low-priority traffic. Each node in the proposed scheme suspends low-priority traffic that corresponds to an impaired primary path after receiving a failure notification and looking up a path-information table including primary paths on the node, backup paths that correspond to the primary paths, and low-priority traffic transmitted by the node. This scheme rapidly suspends low-priority traffic by a process where a failure- detecting node sends a single failure notification for each ring to a source node of the primary path and nodes on the route sequentially suspend low-priority traffic. The simulation results revealed the proposed scheme reduces the failure-recovery time by up to 60 % compared with the conventional scheme.