The routing protocol used by the network layer is AODV. In AODV, to find the destination device, AODV broadcasts out a route request to all of its neighbors. The neighbors then broadcast the request to their neighbors and onward until the destination is reached. Once the destination is reached, it sends its route reply via unicast transmission following the lowest cost path back to the source. Once the source receives the reply, it will update its routing table for the destination address of the next hop in the path and the path cost.