Anonymous Authentication and Key-Agreement Schemes in Vehicular Ad-Hoc Networks

Vehicular ad hoc networks (VANETs) have been the focus of considerable recent research, allowing vehicles to broadcast messages to other vehicles and inform drivers regarding immediate route changes that can improve driving efficiency or avoid accidents. Because vehicles communicate using wireless channels, malicious attacks may occur during the transmission of messages. To ensure security, the accuracy of received messages must be confirmed and the authenticity of the sender must be verified. However, methods designed to ensure VANET security require improvements. For example, the cost of certificate management and the exposure of certificates are major concerns, and roadside unit (RSU) aided schemes cannot achieve real-time authentication. To solve these problems, anonymous-authentication and key-agreement schemes are proposed based on chameleon hashing and ID-based encryption (IBE), respectively. The proposed schemes feature the following properties. (1) Every vehicle can generate numerous chameleon-hash values to represent itself, and RSU can verify the ownership of these chameleon hash values. (2) Private communication between any two vehicles can be achieved by using IBE. (3) The true identities of vehicles are protected. Moreover, the proposed method fulfills numerous security requirements of the vehicular-communication environment.