Physical layer impairment aware wavelength routing algorithms based on analytically calculated constraints

A quality-of-service (QoS)-aware routing engine for a transparent optical network that accounts for physical layer impairments (PLI) is presented. PLI are studied collectively by means of Q-factor. The latter is calculated by analytical methods that speed up the calculation and allow application in a dynamic network. Two path establishment algorithms are deployed: the shortest-path and the shortest widest path. The impact of PLI awareness on the QoS is measured in terms of blocking probability and load balance. Any of the physical parameters can be used as an optimization variable in order to assess their effect on performance degradation at system and network level. The impact of the path establishment algorithm on the optimization parameter is analysed.