Review of Routing Protocols and It's Metrics for Wireless Mesh Networks

WMNs are low-cost Internet access networks built on cooperative routing over a backbone composed of stationary wireless routers. In hybrid mesh WMNs both client mesh and backbone has ability to forward the data to destination. Many ad hoc routing protocols have been adapted to work in WMN without considering the differences between both technologies. Due to the differences between ad hoc network and WMN network, many Researchers started to revisit the routing protocol design of existing wireless mesh networks (WMNs), especially of IEEE 802.11 networks, and ad hoc networks from the perspectives of WMNs which provide Internet for large distances area and consist of two tiers where the heterogeneity exists between them, the heterogeneity between backbone nodes and client nodes are many, for example, the backbone nodes are immobile with a fixed location and high capacity while the client nodes are mobile devices with low capacity and must take care of power consumption and mobility. However, these perspectives should be taken care of in designing the routing protocol to enhance the routing algorithm in order to work well in WMN. There are two ways to enhance the performance of routing protocol in WMN. One way is to improve the metric used in the selection path, the second way is to modify the routing algorithms by considering new characteristics of WMN or integrating the routing protocols with other technologies. In this paper, we present a detailed review of current state-of-the-art routing protocol and its metric for wireless mesh networks in order to provide a better understanding of the research challenges in WMN routing protocol.