Research And Application Of Consensus Mechanism For Internet Of Vehicles

Internet of vehicles(IOV)is one of the most promising and largest market areas in IOT(Internet of things)system,which is of great significance to improve traffic efficiency and safety.At present,there are the following problems in the security of the Internet of vehicles:(1)data integrity problem,the consistency of vehicle data in the process of storage and communication is difficult to guarantee;(2)centralization problem,all the devices of the Internet of vehicles are managed by the central server,when the central server is attacked or malicious behavior occurs,the whole Internet of vehicles will have serious failure.Due to the inherent security of blockchain Technology(such as decentralization,tamper proof,openness and transparency),it is regarded as an emerging technology to effectively solve the security problems of the Internet of vehicles.In order to solve the security authentication problem of the Internet of vehicles,aiming at the characteristics of high mobility and decentralized distribution of vehicles,this thesis designs a blockchain network system based on regional chain and main chain for the Internet of vehicles;furthermore,aiming at the problem of limited equipment resources of the Internet of vehicles,a dpos consensus mechanism based on reputation model is proposed.Specifically,this thesis mainly completes the following work:Firstly,aiming at the dynamic change of vehicles,the network structure of main chain and regional chain combined with blockchain is proposed.The structure divides the whole network into different regions,and implements vehicle autonomy in each region.When the vehicle moves across regions,it interacts with the main chain to realize identity security authentication.The identity information of the vehicle is recorded in the Merkle tree in the main chain block,and the leaf nodes of the Merkle tree are compared to ensure the authenticity and validity of the vehicle information.Secondly,in order to improve the vehicle participation in the main chain regional chain architecture and achieve efficient and safe consensus algorithm,this thesis introduces the vehicle reputation scoring mechanism into the traditional dpos proxyvoting model,and proposes a dpos consensus mechanism based on reputation model.Dpos consensus mechanism based on reputation model can effectively solve the problem of insufficient computing performance of on-board devices.Combined with reputation scoring mechanism,it can prevent malicious nodes from participating in consensus and improve the participation of ordinary nodes.Finally,through simulation experiments,this thesis verifies and analyzes the dpos voting reputation model from three aspects: the relationship between node reputation and region,the influence of malicious nodes on reputation value,and the election probability of malicious nodes.The experimental results show that the cross region authentication scheme of blockchain based on reputation mechanism and dpos can effectively motivate normal nodes to operate and reduce the harm of malicious nodes;and the network structure of main chain and area chain also significantly reduces the overall network overhead,improves the network throughput,and reduces the vehicle authentication time in the network.The research work shows that the architecture of the Internet of vehicles based on the main chain and regional chain can achieve the vehicle identity authentication and information security of each region on the premise of ensuring efficiency and security,and can effectively motivate nodes at the consensus level and reduce the harm of malicious nodes,which has important practical significance.