Topology design of OXC-switched WDM networks

This paper attempts to find a new analytical framework to identify cost-effective topological architectures of optical cross-connect (OXC)-switched wavelength-division multiplexing (WDM) networks. To keep the analysis tractable, we first focus on regular networks and a deterministic uniform traffic model. Regular topologies with symmetries are good approximations of metropolitan area and local area networks but only a fair resemblance of wide area networks. We find that for a regular topology the minimum-hop distance, which is normally used for gauging the size of the network, is an important parameter in dimensioning switching resources. By setting up a first-order cost model and evaluating the tradeoff between network resources, we obtain closed form solutions for the optimal node degree and network cost. For network design under stochastic traffic, we study the worst case capacity dimensioning and blocking probability among the set of all possible stochastic traffic distributions with the same mean and variance. The analytical approach presented in this paper helps us gain insights of parametric dependency of an optimal network architecture on key network design parameters.