A traffic-aware channel re-assignment algorithm for wireless mesh networks

Channel assignment is among the most challenging issues for multi-radio wireless mesh networks, given the variety of objectives that can be pursued and the computational complexity of the resulting problems. The channel assignment problem has been also shown to be inter-dependent with the routing problem, i.e., the problem to determine the amount of traffic flow to be routed on every link. Such a relationship raises the need to re-compute the channel assignment algorithm every time the traffic pattern changes. However, channel assignment algorithms designed to assign channels from scratch will likely return a completely different configuration of radios, which would disrupt the network operation for the time required to enforce the new channel configuration. Such a consideration, along with the observation that channel assignment algorithms may be suboptimal and computationally complex, led us to the design of a simple channel re-assignment algorithm that takes the current channel assignment into account and attempts to cope with the new traffic pattern in the best manner possible while modifying the channel on a limited number of radios. In this paper, we illustrate such a channel re-assignment algorithm and evaluate its performance by means of simulations.