Research On Trusted Join Mechanism Of Nodes In VANET Based On Blockchain

VANET is an important element of intelligent transportation and helps to drive safely.It is of great significance in avoiding collisions and improving traffic congestion.With the wide application of VANET in intelligent transportation,its safety issues cannot be ignored.For example,terminal safety problems of vehicle-mounted platforms,privacy protection problems of vehicles and safety problems caused by malicious vehicle nodes,etc.,all of which will disrupt the normal operation of the network,may cause property damage to drivers,and even endanger personal safety.In order to solve these security problems,the node’s trusted joining mechanism is studied,and the node’s identity,the credibility of the vehicle platform terminal,and the node’s historical performance are judged separately.Judging whether a node is a malicious node by its node identity and historical performance can resist sybil attacks,etc.Through the credible verification of the vehicle platform terminal,it can further improve network security;at the same time,it attaches importance to the security protection of vehicle privacy.In the whole process,once it is found that the vehicle node is malicious,it refuses to join it and guarantees the safety of VANET from the source.The main research contents are as follows:(一)A blockchain-based certificate management model is proposed: This model uses blockchain technology to perform distributed management of certificates representing node identities,which can achieve efficient authentication of node identities.By expanding the data structure of the blockchain,the business chain(Business blockchain,Bus BC)is used to record certificate transactions,and the certificate chain(Certificate blockchain,Cert BC)is used to record certificate operations.The smart contract algorithm that executes the certificate operation ensures the transparency and efficiency of the execution process of the certificate operation;the privacy security protection of the vehicle nodes is achieved through cryptography,and the conversation between the entities is prevented from being tampered during the transmission process.(二)A message-based trust evaluation model is proposed: This model uses the reputation blockchain(Reputation blockchain,Rep BC)to record the vehicle trust value,providing historical evidence that cannot be tampered with for the reputation evaluation when the node is trusted to join.By constructing a message-based credible evaluation function,combined with the idea of Bayesian and weighted evaluation,the vehicle trust value is calculated,and the vehicle trust value is stored on Rep BC.Monitoring of malicious nodes.(三)Put forward the trusted joining mechanism of nodes in VANET: Design the joining process of nodes,the first joining nodes,when they pass the node’s identity and the trusted verification of the vehicle platform terminal,they are allowed to join.Nodes not joining for the first time,in addition to the identity of the node and the credible verification of the in-vehicle platform terminal,a reputation evaluation based on historical performance is also required.When the reputation of the node is greater than the security threshold,it is allowed to join.The verification process of each link is designed.The identity of the node is verified by the certificate management model based on the blockchain,the trusted verification of the vehicle platform terminal is realized by the trusted computing technology,and the reputation assessment of node is verified by the message-based trust evaluation model.The security and performance analysis of the proposed scheme shows that the research in this paper can resist multiple attacks,protect the privacy of the vehicle,effectively identify malicious nodes,further ensure the safety of VANET,and the identity authentication efficiency has been a great improvement.