Research On Privacy-Preserving Authentication Scheme For VANET Based On An Improved Blockchain

In recent years,with the rapid development of economy and technology,the use of vehicles is also increasing,which brings great convenience to people’s transportation,but also increases the risk of traffic accidents.In response to the vehicle safety incidents that have occurred in recent years in vehicle self-organizing networks(VANETs),researchers have identified the lack of vehicle privacy protection and identity verification as the main reasons for the impact.Because in the absence of identity verification,malicious vehicles may forge messages and send incorrect information to relevant vehicles,which can expose the target vehicle’s identity and pose a serious threat to its driver.Thus,it is clear that privacy protection as well as identity authentication of vehicles is crucial in VANETs.However,there are problems in existing privacy-preserving authentication schemes such as opacity of trusted thirdparty activities to individual tuples in the VANETs,insecurity of each component key pair,high workload of revoking certificates,and high computational overhead of identity and message authentication.Therefore,how to effectively protect vehicle privacy as well as identity authentication from VANETs in the era of large-scale,big data networks has become a hot topic and focus of research for many scholars.To address the above problems,based on the VANETs architecture,cryptographic security theory and blockchain-based technology,this thesis proposes an improved blockchain-based authentication scheme for VANET privacy protection,with the following main research work.1.In view of the frequent security incidents in VANETs systems,the advantages and disadvantages of the existing schemes are summarized through the study of VANET privacy protection authentication schemes and the analysis of various traditional privacy protection authentication schemes and blockchain-based VANET privacy protection authentication schemes.2.Verkle Tree is a vector commitment-based scheme for verifying the existence of elements,which has the advantage of not requiring the advantage of Verkle Tree is that it is not necessary to provide the vector commitment proof of sister nodes to verify the existence of an element,but only the proof on the path from the leaf node to the root node.The improved Verkle Tree-based blockchain reduces the proof size,reduces the bandwidth overhead,and improves the efficiency when verifying the existence of transactions.The results of the comparative analysis show that it is feasible to improve the blockchain by replacing Merkle Tree with Verkle Tree.3.To address the security and privacy protection problems of the blockchainbased VANET privacy protection authentication scheme,firstly,a conditional privacy protection distributed authentication scheme without revocation list is proposed based on elliptic curve key generation algorithm,elliptic curve digital signature algorithm and secure hash algorithm mechanism.Secondly,based on the improved blockchain mechanism,a scheme of data protection and certificate storage for vehicular network is proposed.Finally,the security and privacy properties of this scheme are analyzed non-formally.4.Based on the Ethernet consortium blockchain platform,an improved blockchain-based authentication scheme for privacy protection in VANET is implemented.The proposed scheme was compared with existing solutions through simulation experiments,and the results showed that the proposed scheme outperformed existing methods in terms of feasibility and effectiveness.