Proving Reliability of Anonymous Information in VANETs

Advances in wireless communications allow setting up communication links between vehicles for the exchange of information between them. Such vehicular ad hoc networks (VANETs) are important to enhance traffic safety since critical environmental conditions, such as road or traffic conditions, can be rapidly exchanged between vehicles in VANETs. However, to be useful for the driver, the information must be reliable, i.e., with great probability, the received information indeed reflects the actual situation. One approach to this is to regard information as reliable if it is confirmed by various sources. To achieve this, messages received must be distinguishable. This may become a threat against the privacy of drivers since by observing messages, vehicles may be traced. In this paper, we address the mentioned problems. We base the reliability of information on the number of different sources that confirmed specific information, and that number must be greater than a given threshold. We address the nontraceability by letting vehicles change their identity frequently. Our approach scales with respect to storage on the vehicle, as well as management of identities at a certification authority.