WEVAN - A mechanism for evidence creation and verification in VANETs

There are traffic situations (e.g. incorrect speeding tickets) in which a given vehicle’s driving behavior at some point in time has to be proved to a third party. Vehicle-mounted sensorial devices are not suitable for this matter since they can be maliciously manipulated. However, surrounding vehicles may give their vision on another one’s behavior. Furthermore, these data may be shared with the affected vehicle through VANETs. In this paper, a VANET-enabled data exchange mechanism called WEVAN is presented. The goal of this mechanism is to build and verify evidences based on surrounding vehicles (called witnesses) testimonies. Due to the short-range nature of VANETs, the connectivity to witnesses may be reduced with time – the later their testimonies are requested, the lower the amount of witnesses may be. Simulation results show that if testimonies are ordered 5 seconds later, an average of 38 testimonies may be collected in highway scenarios. Other intervals and road settings are studied as well.