Robust channel assignment for link-level resource provision in multi-radio multi-channel wireless networks

In this paper, we investigate the problem of link-level resource provision in multi-radio multi-channel (MR-MC) wireless networks. To quantify robustness of resource provision schemes, we propose the novel concept of interference margin. Using the notion of interference margin, a robust radio and channel assignment problem is formulated that explicitly takes into consideration link-level traffic demands. The key advantage of the proposed formulation is its robustness to channel variability and co-existence of external interference sources. We utilize the generalized Benders decomposition techniques to decouple the radio and channel assignment (combinatorial constraints) and network resource allocation (continuous constraints) so that the problem can be solved efficiently. The proposed algorithm is guaranteed to converge to the optimal solution within a finite number of iterations. We have evaluated our scheme using traces collected from a wireless mesh testbed and simulation studies in Qualnet. Experiments show that the proposed algorithm is superior to existing schemes in providing larger interference margin, and reducing outage and packet loss probabilities.