URP: A unified routing protocol for heterogeneous wireless mesh networks

Wireless mesh networks (WMNs) are taking advantage of multiple radio interfaces to improve network performance, and numerous routing protocols have been proposed for WMNs. However, these routing protocols can not perform well in the heterogeneous multi-radio environment with distinct bandwidth difference, for little attention has been paid to routing overhead balancing. To address this issue, we present a routing protocol called URP (unified routing protocol) which cooperates with distinct bandwidth difference and makes appropriate use of networks to achieve the best performance. In WMNs, a large number of routing messages spread in different channels are duplicated, considering this nodes running URP select a high bandwidth channel set to forward routing messages rather than broadcasting them in each channel. On the one hand, this helps reduce the routing overhead and economize the resource of low bandwidth channels. On the other hand, the low bandwidth channels can contribute their limited resource to improving the throughput. In addition, an advanced expected transmission time (ETT) estimation method accounting for node mobility is implemented in URP, it helps URP considers both the variation of link quality and channel bandwidth to select a route. Simulations show that URP considerably reduces the routing overhead by 25% in heterogeneous WMNs with distinct bandwidth difference compared with OLSR. Moreover, the reduced resource consumption and the advanced ETT estimation method help improve the network throughput.