Research On VANET Privacy Protection Scheme Based On Vehicle Classification In Urban Environment

VANET(Vehicle ad hoc network),is the product that integrated with the transportation industry and the Internet.Vehicle ad hoc networks are providing people with comfortable and safe driving experience with unprecedented intelligence and humanized perfect service.However,many lawbreakers deliberately sabotage the traffic environment,release false information,cause road congestion and violate individual driving routes privacy.In order to avoid being disturbed by the wrong information and to prevent the leakage of personal privacy of users,the methods adopted in the research of this paper are as follows:(1)In the urban road environment,a method of classifying different types of vehicles is adopted,according to their different needs of privacy protection,they are divided into private vehicles and public vehicles,using different signature strategies,to achieve their privacy protection needs.In order to ensure the accuracy of the message,a scheme of multiple signatures of pseudonyms has been adopted.According to the credibility of the vehicle,they are assigned different trust values.Each time a message is signed by the vehicle,the trust value is accumulated until the set safety threshold is reached.Finally,by using SUMO,MOVE,and NS2 for joint simulation experiments compared with other classic VANET privacy protection schemes,it is proved that this scheme improves time efficiency by nearly half.(2)Also in the urban environment,in order to ensure the reliability of the message and better to protect the privacy of users,this article remoulded the most popular blockchain technology and applied it in vehicle ad hoc network.After analyzing the characteristics of the traditional blockchain,two data links are designed for vehicle ad hoc networks when designing the vehicular ad hoc network blockchain.One is the traffic information chain,which is used to link the same traffic information on the same road segment;another is the trust value chain,used for the whole network to jointly maintain the vehicle's trust value.In vehicle ad hoc network blockchain,the vehicle can apply for multiple user addresses for the preservation of the corresponding trust value,in order to motivate the vehicle to send the correct messages,when the information sent by the vehicle is judged to be accurate traffic information,a corresponding trust value reward is obtained,and the vehicle can convert the trust value into cash.At the end of the article,after simulation of the VANET blockchain network environment by using the Hyperledger Fabric network and joint simulation experiments using SUMO,MOVE,and NS2,a comparative analysis of the above scenarios was conducted.The packet loss rate and end-to-end delay variation under different number of vehicles were studied separately.The simulation results show that the above scheme has a good applicability to the urban road environment.