An efficient wavelength assignment method for distributed lightpath restoration in wavelength-routed networks

In distributed lightpath restoration in wavelength-routed network, different restoration operations may compete for the same wavelength on the same link and get blocked even when there are still plenty of idle capacities on the link. In this paper, we propose an efficient wavelength assignment method to lower such kind of blocking. Simulation results show that it significantly outperforms the existing methods. Theoretical analysis confirms the optimality of the proposed method for a special case; while for general cases, it is revealed that optimal performance cannot be guaranteed by any local information-based distributed wavelength assignment method. Furthermore, the applications of the proposed methods in optical burst switching (OBS) networks and distributed lightpath provisioning are also briefly discussed.