A Cross-Layer Architecture for Effective Channel Assignment with Load-Balancing in Multi-Radio Multi-Path Wireless Mesh Networks

Wireless mesh networks (WMNs) are a promising technology for providing Internet connectivity to largeresidential areas. In a typical WMN deployment, end-users access the Internet through a backbone ofstatic routers, which are responsible for traffic forwarding towards the closest Internet gateway (IG). Insuch a scenario, multiple paths may likely exist between the end-users and the IGs. For this reason,multi-path routing schemes appear as a viable approach to provide higher aggregate throughput, faulttoleranceand load-balancing properties. However, route-coupling problems may occur when the pathsare concurrently used and certain nodes on separate paths are within each other’s interference range.To overcome this problem, we propose a cross-layer architecture that comprises a novel joint multi-pathrouting and channel allocation scheme for multi-radio WMNs. The routing scheme discovers multiplenode-disjoint paths between a source node (i.e. the end-user) and the gateway node. During the route setup,channel allocation is performed so that nodes on different paths, but within the same interference domain,transmit on different channels. As a result, the effect of route coupling is strongly mitigated. Moreover,we propose a load-balancing scheme, which allows to distribute traffic among the available node- andchannel-disjoint paths. The simulation results show that the proposed scheme reduces the end-to-end delayand significantly enhances the system goodput over several network topologies and under different trafficworkloads.