A traceable privacy-preserving authentication protocol for VANETs based on proxy re-signature

In this paper, based on a single hop proxy re-signature in the standard model, we introduce a traceable privacy-preserving communication protocol for VANETs. The proposed protocol has some appealing features: The Trusted Authority (TA) designates the Roadside Units (RSUs) translating signatures computed by the On-Board Units (OBUs) into one that is valid as for TA's public key. As a result, the potential danger that vehicles could be traced by the signatures on messages can be well deleted, and attacks are thwarted by using an endorsement mechanism based on signatures. The security analysis shows that the protocol can achieve good conditional privacy target of VANETs.