Decoupled multipath structure for throughput enhancement in wireless mesh networks

Multipath routing is typically utilized in wireless mesh networks for fault tolerance, throughput enhancement, and load balancing purposes. To achieve good route resilience and optimal end-to-end transmission performances, most multipath routing algorithms tend to establish link-disjoint or node-disjoint paths with minimized path costs. Although multiple paths created by these algorithms do not share common links or nodes, they are usually located close to each other. If all these paths are activated simultaneously to boost end-to-end throughput, serious inter-path interferences will happen. In this paper, we first introduce an AODV-based decoupled multipath routing protocol named AODV-DM. AODV-DM builds an insulating region around each established path to prevent new paths from being formed in the neighborhood of the established path. By this means, several "isolated" paths can be created and utilized for simultaneous data transmissions. We also present a novel destination-polling scheme to improve medium access efficiency in destination area, and at the same time alleviate the out-of-sequence problem caused by concurrent packet transmissions through multiple paths. By optimizing the functions crossing network and MAC layers, we are able to complete the design of an efficient multipath structure targeting at end-to-end throughput enhancement. Simulation results demonstrate that the decoupled multipath structure can achieve much higher throughput than single-path and coupled-path cases