A look-ahead unicast routing algorithm in MANETs

A mobile ad hoc network (MANET) is an autonomous system of mobile hosts that are connected via wireless links without prior planning or needs of any existing network infrastructure. The mobile hosts communicate to each other not only as mobile source and mobile destination but also as mobile router in the wireless network. Mobile routers are free to move randomly, thus, incur the risk of frequent communication failures. This causes routing information kept by the nodes to get outdated easily. These problems become more complex in wireless networks, where bandwidth is limited. An efficient and robust routing protocol to address this, therefore, is required. A look-ahead unicast routing (LAUR) routing protocol based on source routing was proposed. LAUR has a route discovery feature that when a source needs to find a routing path to a destination, it does not flood the network with control packets, which is an approach widely used in most of the ad hoc routing algorithms. Instead, the source selects one of its neighbors to send out a route request packet by using the prior information the source acquires from its neighbors to determine an appropriate route that could lead to the destination. Using such information helps the source to prevent selecting a node whose queue is already congested, especially when the network is loaded. The operations in the algorithm are designed to generate a small number of control packets. The proposed LAUR is implemented using GLOMOSIM. Through simulations, we study the performance of the network using the proposed LAUR, and compare with the well known routing protocol, dynamic source routing (DSR) and AODV.