Wavelength Reusability in Wavelength-Routed Optical Networks

Recently routing and wavelength assignment (RWA) problem in wavelength-routed optical networks (WRON's) has been studied extensively. Different optimum criterions are proposed to evaluate the performance of designed networks, such as carried traffic [1], wavelength requirement [2,3], fiber requirement [4], and OXC system scale [5]. Because wavelength is a very limited network resource, most of the research works focus on the wavelength requirements. However, for the non-uniform traffic pattern, the wavelength requirement Nλ will increase with the traffic loads increased, it is difficult to evaluate the network performance by using wavelength requirement. In this paper, we will take wavelength reusability ρ as a network performance criterion. By using a novel heuristic RWA algorithm, we evaluate the wavelength reusability of several real planned transport networks. In addition, a large number of randomly generated WRONs are analyzed in order to quantify the relationship between wavelength reusability and network topology parameters, such as average nodal degree, etc.