Layer-2 multi-hop IEEE 802.11 architecture: design and performance analysis

The problem of extending the network coverage in wireless local area networks has recently received significant research and industrial attention. IEEE 802.11 specifications allow only one hop communication between nodes. The authors propose and develop a layer-2 bridging architecture and solution to increase the range of an 802.11 access point using ad hoc networking. In the proposed framework, nodes are logically divided into levels based on their distance (hops) from the access point, and a layer-2 bridging tree is built based on the level concept. The specific mechanisms for the forwarding tree establishment as well as for the data propagation are introduced and discussed. An analytical model is also presented in order to analyse the saturation throughput of the proposed mechanism, while its applicability and effectiveness are evaluated via modelling and simulation. The corresponding numerical results demonstrate and confirm the significant area coverage extension that can be achieved by the authors' solution, when compared with the conventional 802.11b scheme.