A Practical Authentication Framework for VANETs

In vehicular ad hoc networks (VANETs), conditional privacy preserving authentication (CPPA) scheme is widely deployed to solve security and privacy issues. Existing CPPA schemes usually require ideal tamper-proof devices (TPDs) on vehicles which, however, might be infeasible or do not exist in reality due to high security requirements. To address this problem, we propose a practical framework of CPPA scheme that supports more realistic TPDs which are less secure correspondingly. We demonstrate that this framework also manages to achieve nonframeability in addition to other security objectives including nonrepudiation, conditional privacy preserving, and unlinkability. Moreover, performance analysis shows that our framework has better efficiency in authentication. All these features make our framework practical for VANETs.