Research On Blockchain-based Data Storage Technology For VANET

With the concept of intelligent transportation,VANET as its main supporting tech-nology has ushered in the opportunity of rapid development.With the gradual expansion of the network scale,more and more vehicle nodes are connected to the network,and huge amount of VANET data is transmitted and shared in the network,which puts forward more strict requirements on the security and efficiency of VANET data storage.The existing VANET technology has certain shortcomings in the security and efficiency of data stor-age,such as the centralized storage method is vulnerable to malicious attacks that lead to the tampering and leakage of users’ personal data.In order to solve these shortcomings in the security of VANET,blockchain technology is introduced into VANET in this thesis to ensure the security and efficiency of data storage in VANET by using the decentralization and anti-tampering features of VANET.The main research contents of this thesis are as follows.(1)In response to the current problems of data leakage,data tampering and other inse-curity problems in the data storage of VANET,this thesis proposes a secure storage scheme for VANET data based on attribute encryption.The scheme combines blockchain and at-tribute encryption technology to achieve secure storage and fine-grained access control of VANET data.All the hash values of the data are stored on the blockchain,eliminating the possibility of data tampering.At the same time,users can decide that the data is only open to specific users by setting access policies,preventing the problem of data leakage.This thesis also improves the traditional attribute confidentiality algorithm,which enables the high-performance RSU nodes to cover most of the computational overhead and re-duces the performance burden of vehicle nodes.The simulation experiments show that the scheme of this thesis,under the premise of ensuring security,can store and share data more efficiently and can further improve the data storage efficiency of vehicle nodes.(2)To address the problems of large storage footprint and low storage efficiency caused by traditional blocks used for vehicular data storage,this thesis proposes a lightweight block storage scheme based on LT coding.In this scheme,the RSU nodes in the core net-work slice the blocks and store a certain number of coded blocks,while the vehicle nodes in the edge network only store the latest blocks to anchor the whole block chain.This can greatly reduce the storage space consumption of the whole network due to storing blocks.At the same time,in order to speed up the rate of vehicle nodes in block checking,this scheme proposes a jumping block checking algorithm,by which the complexity of block checking can be reduced to a constant level and will not increase linearly with the increase of chain length,which greatly reduces the storage pressure of vehicle nodes and the block transmission overhead of the whole network.Through simulation experiments,this scheme has a significant improvement in block storage space occupation and block recovery success rate compared with the random deletion method under the same condi-tions,which shows that the scheme of this thesis can save storage space more efficiently and can ensure sufficient system security.