Routing Metric of Expected Delay in Multi-Radio Multi-Channel Wireless Mesh Networks

Many routing metrics have been proposed to improve the performance of wireless mesh networks (WMNs). Most of these routing metrics describe intra-flow and inter-flow interference respectively, which brings in adjustable parameters or results in non-isotonicity. However, the adjustable parameters, used to balance the intra-flow and inter-flow interference, are difficult to adapt to the network status, and non-isotonicity makes the design of routing metric complicated. In this paper, we propose an isotonic metric of expected delay (MED) in multi-radio multi-channel (MRMC) WMNs. In particular, MED uses the expected available bandwidth (EAB), which can capture the logical intra-flow and inter-flow interference uniformly, to estimate the delay of the path. In MED, both expected packet transmission delay and expected queuing delay are estimated to capture physical interference, logical interference, load and noise comprehensively. Simulation results show that the proposed metric can improve overall network performance effectively.