Optical path strategies in WDM all-optical networks: minimization of wavelength converters in optical cross connects

There is a significant debate in progress about the need for translating the wavelength of a signal within an optical network and on the comparison of the performance of the wavelength path (WP) and virtual wavelength path (VWP) approaches. This paper investigates these issues in more depth. An analysis of the algorithms allowing VWP and WP schemes is reported. Their performances are compared in terms of the number of ports of each network node. A wavelength rearrangement algorithm is proposed which allows the performance of VWP scheme to be reached, with a greatly reduced total number of wavelength converters with respect to that corresponding to VWP. The results show a drastic reduction of the wavelength converters in each node, permitting a significant reduction of the optical cross connects (OXC) costs