A network flow approach for static and dynamic traffic grooming in WDM networks

In WDM networks, traffic grooming is a fundamental and important operation for aggregating multiple low-rate channels from the end users into a high-rate wavelength channel. In the literature, several traffic grooming problems were formulated where the common objective is to minimize the number of add-drop multiplexers required, and each of these problems was solved by specific algorithms. In this paper, we propose a network flow approach for solving a class of static and dynamic traffic grooming problems. In this approach, we transform a traffic grooming problem onto the minimum edge-cost flow problem through proper graph transformation and assignment of edge weights, and then solve this resulting network flow problem by an efficient heuristic algorithm. The network flow approach has two main advantages: (1) It is generally applicable to many static and dynamic traffic grooming problems. It can solve some existing traffic grooming problems as well as new problems that cannot be solved by the existing algorithms. (2) It performs at least as good as the best existing algorithm for static traffic grooming and significantly outperforms the existing algorithms for dynamic traffic grooming.