Impairment-aware backward recursive PCE-based computation algorithm for wavelength switched optical networks

In transparent wavelength switched optical networks (WSON), physical impairments (PI) may be accumulated along the lightpaths which are set up entirely within the optical domain. The lightpaths may not be established successfully due to physical impairments accumulation. Path computation in multi-domain optical networks has attracted much attention, and a backward recursive PCE-based computation approach (BRPC) has been proposed. However, PI has not been considered in path computation in multi-domain scenario up to now. In this paper, an impairment-aware backward recursive PCE-based computation algorithm (IA-BRPC) is proposed for multi-domain wavelength switched optical networks, and simulated with discrete event simulation tool OMNeT++. Numeric results show that IABRPC can achieve better performance with blocking probability than standard BRPC.