Sybil Nodes Detection Based on Received Signal Strength Variations within VANET

A Vehicular Ad hoc Network is a collection of mobile hosts forming a temporary network without the aid of any established infrastructure. This flexibility in space and time induces new challenges towards the security needed to support secure communications. Indeed, VANET are subject to attacks due to their vulnerabilities; one of the most compromising attacks is the Sybil nodes attack. We present in this context a Sybil detection approach, based on received signal strength variations, allowing a node to verify the authenticity of other communicating nodes, according to their localizations. In addition, we define an estimated metric of the distinguishability degree between two nodes, allowing to determine Sybil and malicious ones within VANET. The applicability of our contributions is validated through geometrical analysis, simulations and real measurements.