Research On Privacy Protection And Fair Payment In Blockchain-Based V2G Network

With the rapid popularization of new energy vehicles,vehicle-to-grid(V2G)has received extensive attention.As an important part of the smart grid system,V2 G networks allow the two-way flow of energy and information between electric vehicles and smart grids to mitigate fluctuations caused by renewable energy connecting to the grid.However,when electric vehicles and smart grids communicate,sensitive information such as vehicle location,battery usage,user identity and transaction amount are at risk of leakage,posing a potential threat to user privacy and security.The existing V2 G network privacy protection solutions usually use a trusted third party(TTP)as the payment system,but TTP may collect user information illegally during the service process and harm the interests of users.And the existing solutions focus on the research on privacy protection in the process of user registration and authentication,and how to ensure fairness in the transaction process is still an urgent problem to be solved.In response to the above problems,this thesis conducts research on privacy protection and fair payment in V2 G networks.The specific work results are as follows:1.A fair payment scheme with privacy protection based on the UTXO model and time commitment.The scheme adopts the blockchain based on the UTXO model as the underlying payment platform,and uses the Bitcoin-based Timed Commitment Scheme to ensure fairness in the service process of electric vehicles and smart grids.Aiming at the lack of privacy protection mechanism in the traditional time commitment scheme,the scheme uses zero-knowledge proof and cryptographic commitment to hide sensitive information in the transaction process between the two parties.Security analysis shows that the scheme meets the expected security goals under the Universally Composable Framework(UC).Further experimental analysis also shows that the scheme has certain practicability.2.Decentralized payment scheme based on account model and smart contracts.Considering the limited computing resources of devices in the Io T environment,the scheme puts time-consuming cryptographic calculations on the side of the smart grid,reducing the burden on electric vehicles.In order to speed up transactions and reduce the intermediate fees required for smart contract execution,the scheme puts the transaction process off-chain,and the service provider(electric car/smart grid)only needs to submit cryptographic credentials to the smart contract when the transaction is completed to obtain the corresponding remuneration.At the same time,the scheme adopts penalty and commit-and-claim mechanisms to ensure the fairness of users.Due to the openness and transparency of blockchain and smart contracts,the scheme uses efficient zero-knowledge proofs and asymmetric encryption to hide the user’s real identity and transaction amount,striking a balance between efficiency and privacy.This thesis gives the security analysis under the UC model and the performance comparison with related schemes,indicating that the scheme has stronger practicability and higher efficiency.