A divide-and-conquer scheme for assigning roles in multi-channel wireless mesh networks

A multi-channel MAC is a promising approach for improving network throughput by multiplexing transmissions over orthogonal channels. Molecular MAC has recently adopted this approach by proposing to modify the standard IEEE 802.11 DCF. It requires role and channel assignment to nodes: some of them use a static channel while others dynamically switch to neighbor channels on-demand. To assign roles and channels, we extend the notion of the Weakly Connected Dominating Set, a structure already used in clustering. We adapt it by introducing new constraints to define what we call a reversible WCDS (r-WCDS), which is particularly suitable for Molecular MAC. We propose a divide-and-conquer scheme that partitions the network into clusters with one leader per cluster solving a MILP formulation to assign roles in its cluster. By appropriately defining the roles at the border of clusters, we maintain global connectivity in the r-WCDS. Our simulations show that the performance of our strategy is close to a centralized algorithm.