Research On Authentication Techniques With Privacy Preserving In Vehicular Ad-hoc Networks

Vehicular Ad hoc Networks (VANETs), as a kind of special mobile ad-hoc networks, have been found many promising applications. A lot of research workers throw themselves into it. Preventing malicious adversary attack networks and ensuring network security in VANETs have become the research hot-spot.In this paper, we aim at the authentication problem in the VANETs. We have focused attention on the authentication techniques with privacy preserving. Generically, the methods of the authentication in our daily life can not provide the function of privacy preserving. The essence of this problem is that the authenticated certificate or data need to be hidden or be used more than once. Multiple certificate authentication system is the common methods to solve these problems. However, considering the node size of the VANETs, Multiple certificate authentication system should be checked out in a long terms. Most of researchers tend to gain the reusable certificate or representative identity data via cryptography technology.We have designed the different authentication schemes with privacy preserving according to the different communication models in VANETs. Moreover, other cryptographic primitives that are considered to play a key role in VANETs have been discussed in this paper. Our contributions are presented as follows:Firstly, an identity escrow scheme with appointed verifier for VANETs is proposed. Considering the communication between the vehicles and the special participants, we employ various techniques such as the proof of knowledge, verifiable encryption, hidden identity signature, and so on. We also extend and refine the model of Camenisch's scheme. Therefore, our scheme gains the existing required security property.Secondly, a new authentication protocol for the communication between vehicle to vehicle is proposed by using a safe dynamic accumulator. Naturally, both the add operation and the revoke operation are feasible via dynamic accumulators. So, this technique seems to be practical in open communication environment (just like VANETs). Certainly, if there is a disputation, we could easily open the real identity of the dishonesty participants.Thirdly, a certificateless public-key blind signature with private mutual authentication scheme is proposed. Since the blind signature is important for providing the authentication with privacy preserving, the research based on the certificate-less system is match to the idea for lighting the load of the certificate server and solving the key escrow problem. Morever, the proposed scheme is proved against the adaptive chosen-message attack in the random oracle model. Finally, in regard to many schemes have a supposed secure channel and the participants need special private communication in VANETs. We propose a practical and secure key agreement protocol for VANETs by using password authentication. Our protocol contains two sub-protocols: a key agreement protocol between one vehicle and the server; a key agreement protocol between one vehicle and one vehicle through cooperating with the server. The proposed scheme can resist to all the known attacks and satisfy many of desirable security requirements.