Securing Vehicular Networks Using Deterministic Schemes for Computing Trust

Vehicular ad-hoc networks (VANETs) have a big potential to improve traffic conditions. However, they are exposed to security threats that influence their reliability because they use an open medium for communication. We propose a trust based security system used by drivers to receive only trustworthy information about traffic conditions. Trust indexes are computed for individual pieces of data referring to a specific event, regardless to the source of data. The drivers use the software system to evaluate the trust in the received information. Each node disseminates trust indexes to other vehicles, helping to increase the accuracy in the trustworthiness of an event. The performance was evaluated using modelling and simulation. The results show that several data falsification attacks like message alteration and message fabrication are successfully prevented and the messages from the malicious drivers are ignored if the number of attackers is less than 30% of the total number of drivers.