Interworking Wireless Mesh Networks: Performance Characterization and Perspectives

In this paper, we consider multi-mode, multi-radio wireless mesh networks and investigate the impact when multiple wireless mesh networks overlap in service area. We formulate the problem of resource sharing as a network optimization problem, and present a general LP (linear programming) formulation for modeling the problem. We first find that in a system with multiple wireless mesh networks in overlap, individual mesh networks could suffer from capacity degradation if no form of inter-domain coordination is present. Therefore, it is desirable to "interwork" these wireless mesh networks by allowing inter-domain traffic relay through provisioning of "bridge" nodes. If bridge nodes are chosen arbitrarily without any careful planning, however, serious inefficiency and unfairness problem may result. We use the proposed LP formulation to show the impact of bridge node selection and performance tradeoffs between throughput unfairness and network capacity when interworking multiple wireless mesh networks. Based on simulation results, we conclude that if proper interworking is provided, significant performance gain can be obtained for overlapping wireless mesh networks.