Secure Data Downloading with Privacy Preservation in Vehicular Ad hoc Networks

In this paper, we propose a secure data downloading protocol with privacy preservation in vehicular ad hoc networks (VANETs). In the data downloading application, vehicles send requests, such as where is the nearest gas station, at a road side unit (RSU) and receive the corresponding responses from application servers via current or the following RSUs. It would be easy for eavesdroppers to get vehicles' private information if semi-trust RSUs are compromised because both request and response messages are forwarded by them. Therefore, we develop a protocol which enables vehicles to download data securely from RSUs with their privacy under protection even when one or multiple RSUs are compromised. Our protocol guarantees vehicles exclusive access to their requested data while eavesdroppers can not obtain any private information of the vehicles. Possible attacks and the corresponding solutions as well as privacy evaluation are discussed to demonstrate the performance of the proposed protocol.