Location security in geographic ad hoc routing for VANETs

Vehicle-to-vehicle communication among vehicular ad hoc networks (VANETs) plays an important role in providing a high level of safety and convenience to drivers. Geographic routing protocol has been identified to be suitable for VANETs because of the special nature of such networks, e.g., frequently changed network topology and high dynamic mobility. There is considerable functional research about geographic routing, but the node location security issues have not been vastly concentrated on so far. While selecting every hop, the performance and security can be impacted severely by false position because of the position information importance for geographic routing. Making use of directional antennas, we propose a novel detection mechanism capable of recognizing nodes faking about their positions in beacon message. By checking through which directional antenna beacon messages are received, ones' neighborhood can be easily divided into two groups. In addition, combined with the three malicious node detection rules, nodes can efficiently detect malicious nodes around them after exchanging neighbors grouping information with each others. As the evaluation based on simulations shows, our position verification system can detect malicious nodes successfully and can prevent attacks on geographic routing by false position.