Routing and grooming of scheduled lightpath demands in a multi-granularity switching network: a mathematical model

Abstract

Technological improvements allow advanced optical cross-connect architectures to be developed. Multi-granularity switching optical cross-connects (MG-OXCs) are equipments able to switch wavelengths, to aggregate (disaggregate) wavelengths into (from) groups of wavelengths called wavebands and to switch wavebands. In previous studies, we described a new traffic model based on Scheduled Lightpath Demands (SLDs) that make it possible to take into account the time and space distribution of traffic in the planning of all-optical WDM mesh networks. We proposed a mathematical model to optimize the routing of a set of SLDs in a WDM with standard wavelength-switching optical Cross-Connects (WXCs). In order to compare the cost of provisioning a set of SLDs in a network of WXCs against the cost of instantiating the same set in a network of MG-OXCs, it is necessary to extend the model used for the standard case. In this paper, we present a generalization of the model that permits to solve the problem of optimally instantiating SLDs in a network equipped with MG-OXCs.