Flooding technique is often used for route discovery in on-demand routing protocols in mobile ad hoc networks (MANETs) such as Dynamic Source Routing (DSR) and Ad hoc On-demand Distance Vector (AODV) routing. In this paper we present a Positional Attribute based Next-hop Determination Approach (PANDA) to improve the performance of flooding-based route discovery in MANETs using positional attributes of the nodes. These attributes may be geographical, power-aware, or based on any other quality of service (QoS) measure. We identify the "next-hop racing" phenomena due to the random rebroadcast delay (RRD) approach during the route discovery process in DSR and AODV, and show how the PANDA approach can resolve this problem. We assume that each node knows its positional attributes, and an intermediate node can learn the positional attributes of its previous-hop node via the received route-request message. Based on the attributes such as the relative distance, estimated link lifetime, transmission power consumption, residual battery capacity, an intermediate node will identify itself as good or bad candidate for the next-hop node and use different rebroadcast delay accordingly. By allowing good candidates to always go first, our approach will lead to the discovery of better end-to-end routes in terms of the desired quality of service metrics. Through simulations we evaluate the performance of PANDA using path optimality, end-to-end delay, delivery ratio, transmission power consumption, and network lifetime. Simulation results show that PANDA can: (a) improve path optimality, and end-to-end delay, (b) help find data paths with only 15%-40% energy consumption compared to the RRD approach at a moderate cost of increased routing messages, (c) balance individual node's battery power utilization and hence prolong the entire network's lifetime.
