Research On VANET Privacy Protection Scheme Based On Anonymous Exchange

Through the communication between vehicle and infrastructure,and the communication among vehicles,VANET provides vehicles with information of other vehicles and traffic,which can realize traffic accident warning,driving assistance,entertainment,internet access and so on.VANET play an important role in intelligent transportation system(ITS)in the future.However,VANET communicates by wireless network.Compared with general mobile ad-hoc network,Vehicular Ad Hoc Network has large and complex members.At the same time,the mobile wireless channel is open and the trajectory is foreseeable,it is inevitably suffer from a lot of threat and security problem.To achieve various services provided by VANET,vehicles need to periodically broadcast Safety Beacons,which include the information of real-time position and identity.This information is easy to be misused by attacker to threaten users’ privacy.To protect vehicles’location privacy,researchers mainly adopt Mix-zone,Group-navigation,k-anonymous,PIR scheme and so on.In this paper,we analyze the threats,requirements and challenges of VANET security.And we have further studied the problem of vehicle location privacy protection.In view of the limit of time and neighbor number at pseudonym update in the existing scheme of VANET location privacy protection,we proposed a pseudonym exchange scheme based on dynamically generated group(PSDG).In the scheme,vehicles exchange pseudonym within group,and accumulate the whole probability of pseudonym mixture to improve the effect of location privacy protection.In addition,one-way hash chain is adopted to dynamically generate two pseudonym stacks,which not only induces the cost of pseudonym management,but also guarantee the privacy in the process of pseudonym exchange.In order to verify the effectiveness of the proposed scheme,we make use of simulator to evaluate the performance of the PSDG scheme.The results of simulation show that our scheme can significantly reduce the probability of being track,and improve the effect of vehicle location privacy protection.