Latency aware anypath routing and channel scheduling for multi-radio wireless mesh networks

Wireless mesh network (WMN), radio nodes that form a mesh topology, is an interesting architectural candidate for the future wireless Internet. A dense access network can rapidly be deployed at a reasonable cost because there is no need to wire the mesh access points. However, WMNs typically do not perform well with latency-sensitive data traffic, such as Voice over IP (VoIP), due to restricted bandwidth. In this paper, we present the design, implementation and evaluation of LA-AP-OLSR for hybrid WMNs, where mesh nodes have two radios; a fixed radio for receiving and a switchable radio which rapidly changes channels to send to neighbor nodes. The key novelty of our approach is to use any path routing for latency-sensitive traffic while normal traffic is treated using single path routing. Also, we develop a novel queuing strategy which prioritizes latency-sensitive traffic. A detailed evaluation using KAUMesh, an in-house multi-radio wireless mesh testbed, shows a reduction in latency and packet loss for VoIP traffic without negatively impacting competing TCP background traffic.