Simulated annealing for interface-constrained channel assignment in wireless mesh networks

The channel assignment problem in wireless mesh networks is considered in this paper. Due to the limited number of radio interfaces that each node is equipped with, channel assignment must ensure that the interface constraint is obeyed, i.e., the number of different channels assigned to the links incident on a node must not exceed the number of interfaces the node is equipped with. However, interface constraint may be one of the causes that hinder the performance of some of the existing heuristics. In this paper, we use simulated annealing to solve the channel assignment problem in wireless mesh networks. We consider using two neighbor generating approaches that handle the interface constraint in different ways. The first approach generates random solutions that need not conform to the interface constraint. With the incorporation of a penalty function technique, the solutions gradually converge to feasible solutions. The second approach allows only feasible solutions to be generated during the simulated annealing process. Simulations are conducted that compare our proposed simulated annealing algorithms with a tabu-based algorithm under different network settings and traffic scenarios. The results show that our algorithms exhibit improved network performance over the tabu-based algorithm.