Hybrid anonymous message broadcast for VANETs

At present, the number of cars is increasing rapidly. There is a growing need for participants to be able to communicate with each other in order to increase the efficiency of transport and the safety of vehicles and pedestrians. The Intelligent Transportation System recommends the use of Vehicular Ad-hoc networks for this purpose. A cryptographic protocol is proposed, where eligible vehicles can authentically and anonymously report road conditions (e.g. traffic jams, accidents, etc.). Our proposed solution is hybrid, globally it is PKI-based, locally identity-based cryptography is applied and two lists are handled. It takes advantage of bilinear pairings, the devices do not store the master secret key, provides batch verification of messages, moreover the anonymity of the senders can be revoked. We also demonstrate the security analyses of the protocol in applied pi calculus with the help of the ProVerif tool. We show that the proposed protocol provides mutual authentication for parties and token secrecy during the Communication Setup, moreover anonymous message authentication in phase of Incident Report. We have also implemented the proposed protocol in Python and demonstrated that it is suitable for practice.