2.5. 3 WMNs routing protocols
Wireless mesh networks have emerged as a key technology for
next-generation wireless networking, because of their advantages over
other wireless networks [44].
WMNs routing protocols are mechanisms to transfer information in data
packets from a source to a destination in a network [49]. Generally, two
activities take place in routing protocols which enables communication to
occur between two nodes. The first activity is to determine optimal routing
paths and the transferring of packets through the network but still using low
computing power. The second thing is to achieve these activities; each
routing protocol uses different metrics to evaluate the best path that data
packets should use when sending packets in a network [5 0 ]. Routing
protocols use several metrics to calculate the best path for routing the
packets to its destination. These metrics are a standard measurement that
could be number of hops, which is used by the routing algorithm to
determine the optimal path for the packet to its destination. The process of
path determination is that, routing algorithms initialize and maintain
routing tables, which contain the total route information for the packet.
This route information varies from one routing algorithm to another [48].
2.5. 4 Routing approaches for WMNs
Routing protocols developed in recent years are classified into
three broad categories. These are: flat, hierarchical and geographical
routing. Hierarchical routing plays a major role in large size networks
where flat routing protocols are struggling with constraints. Now-a-days
geographical location information also provides better routing performance
in ad-hoc networks [ 49 ]. The present study focuses on the flat routing
scheme because of the WMN does not need to maintain any specific
structure such as hierarchy, and every node perform the same
functionalities. The flat protocol saves the communication overhead caused