DWDM Fast Lightpath Setup Using Network Status Information

Techniques are presented herein to setup a wavelength on a path from a source node to a destination node. Cross-talk margin information already computed for one or more installed wavelengths is obtained between the source node and destination node. A total margin as a function of the cross-talk margin information is computed. A determination is then made as to whether to perform non-linear impairment validation of the wavelength based on the total margin. These techniques may be generalized to account for coherent and non-coherent portions of a network.