On the revocation of malicious users in anonymous and non-traceable VANETs

Abstract

For the proper performance of Vehicular Ad-hoc NETworks (VANETs) it is essential to protect the service against malicious nodes aiming at disrupting the proper operation by injecting fake, invalid data into the network. It is common to define a traditional identity-based authentication for vehicles, which are loaded with individual credentials. However, the use of these credentials in VANETs may allow vehicle tracking and thus violate users’ privacy, a risk that can be overcome by means of anonymity schemes. This comes at the expenses, however, of on the one hand preventing VANET authorities from identifying malicious users and revoking them from the network, or on the other hand to avoid anonymity of users in front of the CA thus to allow their revocation. In this work, we describe a novel revocation scheme that is able to track and revoke specific users only after a number of complaints have been received while otherwise guaranteeing vehicle’s anonymity.