Route-metric-based dynamic routing and wavelength assignment for multifiber WDM networks

We present three dynamic routing and wavelength assignment (RWA) algorithms that are intended for multifiber WDM networks without wavelength converters. For networks with a large number of wavelengths per fiber and/or a large number of fibers per link, our algorithms exhibit particularly good performance, and one of them significantly outperforms other existing algorithms. In response to a connection request, our algorithms first select a physical route among a set of predetermined routes on the basis of some per-route variables. The algorithms then select a wavelength to be used with the selected route. This paper illustrates how we can rethink the criteria for route selection in multifiber networks. We also suggest a method of selecting the set of predetermined routes to balance the traffic load. Our simulation results illustrate that this method exhibits significantly lower blocking probability than the traditional shortest-route-based method. Thus, this paper also illustrates that the choice of predetermined routes can significantly affect the blocking probability of an RWA.