Throughput and energy-aware routing for 802.11 based mesh networks

In this paper we propose a novel routing algorithm for 802.11 based wireless mesh networks called Energy and Throughput-aware Routing (ETR). The design objectives of ETR are (i) to provide flows with throughput guarantees, and (ii) to minimize the overall energy consumption in the mesh network. To achieve these objectives, we first analyze the throughput performance of the mesh network. Based on this analysis, we target obtaining the set of feasible allocations in the wireless network, i.e., the capacity region, which results in a set of complex non-linear equations that are not adequate for optimization algorithms. To overcome this computational complexity we derive a set of linear constraints (referred to as linearized capacity regions) which provides a much simpler formulation at a slightly reduced accuracy. By feeding these linear constraints into an integer programming formulation, we then propose a routing algorithm that admits as many flows as possible while satisfying their throughput guarantees. This algorithm is further extended to account for energy considerations by devising a routing algorithm that uses as few nodes as possible, which allows switching off the unused nodes and thus save energy. The proposed approach is thoroughly evaluated and shown to outperform previous approaches very substantially both in terms of throughput and energy consumption.