Non-exhaustive routing and wavelength assignment

Routing and Wavelength Assignment (RWA) is one of the most important issues in all wavelength-routed optical Wavelength Division Multiplexing (WDM) networks. We introduce a non-exhaustive technique for RWA in WDM networks without wavelength conversion under different load conditions. The non-exhaustive technique will choose a wavelength/path from the source to the destination according to a stochastic process. The aim of using this non-exhaustive technique is to limit the number of wavelengths/paths pursued in the call setup phase. We analytically compare the effect of limiting the number of wavelengths/paths pursued during the call setup phase. The proposed non-exhaustive RWA uses a small number of wavelength/path attempts for a call setup, but the call blocking probability is comparable to the exhaustive technique. Furthermore, the technique is generalized by using dynamic probability distribution. The distribution is updated using the learning automata concept in which good selections are rewarded and bad ones are punished. We demonstrate the ability of this technique to achieve fairness among different source/destination pairs. The results presented indicate the benefits of using the non-exhaustive technique for dynamic routing and wavelength assignment in WDM networks