Comparative Study of Classical and Optically-Optimized Route and Wavelength Assignment Algorithms

We formulate and solve modified route and wavelength assignment (RWA) algorithms that take into account the optical impairments of fiber links such as signal attenuation and dispersion. We note that the modified formulations account for slightly different objectives than those of classical formulations which tend to minimize hop count, the number of wavelengths required, or maximize throughput while completely ignoring the physical limitations of fiber links. Our results show significant differences in route and wavelength allocations which lead to improved average throughput per link for a marginal increase in the number of required wavelengths for both static and random traffic demands.