Joint Channel Assignment and Multi-Path Routing for Multi-Radio Wireless Mesh Networks

Multi-radio Wireless Mesh Networks (MR-WMNs) are being increasingly deployed to provide affordable Internet access on large residential areas. MR-WMNs allow the supported mesh clients (MCs) to access the Internet gateway by multi-hop packet forwarding over the mesh routers (MRs), which can be equipped with multiple radio interfaces. In such a scenario, the routing protocol should (i) decide the address of the next-hop node and the radio-interface to be used for each transmission and (ii) exploit the presence of multiple paths between the MCs and the Internet gateways. To address these issues, we propose a cross-layer architecture that comprises a novel joint multi-path routing and channel allocation scheme for MR-WMNs. During the route setup, multiple node-disjoint paths are discovered and channel allocation is performed so that nodes on different paths, but within the same interference domain, transmit on different channels. Moreover, we propose a load-balancing scheme, which allows to distribute traffic among the available node- and channel-disjoint paths. The simulation results show that the proposed scheme reduces the end-to-end delay and enhances the system goodput significantly over several network topologies and under different traffic workloads.