ELCP: An Effort-Based Least Cost Path Scheme for MANETs

To weaken the selfish behavior of nodes in mobile ad hoc networks, many payment-based incentive schemes have been proposed recently, yet it is still far from achieving the expected efficiency to encourage node cooperation. In these schemes, source node selects a Least Cost Routing (LCP) for data transmission according to the forwarding cost reported by intermediate nodes and rewards them with some virtual money before or after successful packet forwarding. However, as a result of information asymmetry between source and relay nodes, nodes on LCP may degrade their efforts promised in the previous routing discovery stage if there is no enough motivation for them to work hard, which exercises a negative influence on the forwarding efficiency of LCP schemes. Therefore, the actual transmission efforts of intermediate nodes must be considered by the source node in the processes of route selecting and packet forwarding. In this paper, with adoption of principal-agent theory of economics, we propose a novel LCP scheme (ELCP) based on the intermediate nodes´ effort to stimulate nodes cooperation, in which both source and relay nodes can maximize their profits and ensure routing efficiency simultaneously.