Mutual Authentication Framework With Conditional Privacy Protection In VANETs

As an important part of the intelligent transportation system,the development of the Vehicular Ad-hoc Networks(VANETs)has been attracting the attention of various circles at home and abroad.However,due to the openness of the wireless access medium and the characteristics of the vehicular ad-hoc network,it is very vulnerable to various attacks from the outside world,which seriously affects the widespread deployment and application of the vehicular ad-hoc network.In order to ensure the safety of road traffic and protect the privacy of users,providing effective anonymous identity authentication in vehicular ad hoc networks has become a hot topic today.Most of the current authentication schemes adopt traditional pseudonym conversion schemes,which mainly consider authentication efficiency,but ignore the problem of user privacy disclosure caused by pseudonym conversion in the authentication process.In addition,traditional authentication schemes concentrate the authentication records on the third party.If the third party suffers serious network attacks,it will cause a series of security problems.In view of the above problems,this paper proposes a mutual authentication framework with conditional privacy protection,which is used to protect the route privacy of the vehicle during the identity authentication process,ensure the efficiency of authentication,and ensure that the authentication records will not be tampered with.First,the identity-based mutual authentication framework with conditional privacy protection uses identity-based signature schemes and online/offline signature schemes to achieve anonymous identity authentication between vehicles and roadside facilities and between vehicles.The framework uses the method of dynamically generating pseudonyms,which changes the disadvantages of the traditional pseudonym replacement scheme,protects the route privacy of the vehicle,and also reduces the storage requirements of the vehicle.Secondly,the blockchain-based mutual authentication framework with conditional privacy protection introduces blockchain technology on the basis of the original framework,using the distributed,non-tamperable and decentralized characteristics of the blockchain to reduce the risk caused by single point of failure of the third party and ensure the integrity and security of the authentication records.Besides,the framework also prevents the misuse of pseudonyms by combining the one-way hash keychain.Finally,the results of formal verification and simulation experiments show that the framework proposed in this paper has better authentication efficiency in the process of identity authentication and meets the needs of user privacy protection.To sum up,the mutual authentication framework with conditional privacy protection has good performance in the aspects of identity authentication and privacy protection,and has good reference value for the research on the security and privacy protection in vehicular ad-hoc networks.