Research On Key Technology Of Privacy Protection Based On Blockchain

In the era of increasingly open networks,technologies such as big data,4G/5G,and the Internet of Things(IoT)are booming.The Internet has gradually broken the traditional model and began to move towards dynamic and heterogeneous interconnections.Various applications based on different networks are becoming more and more popular,bringing great convenience to the country,society and individuals,such as government affairs,management,finance,online shopping,social and other fields.But they also bring new technical challenges to sensitive data privacy protection.The privacy issue covers almost every corner of the Internet and has gradually become a huge stumbling block to the advancement of Internet technology.This paper analyzes the current development of privacy protection and starts with the key issues of privacy protection technology,combining the hash function,asymmetric encryption,homomorphic encryption,etc.,using the features including traceability,decentralization and non-tampering of blockchain technology,research and exploration in-depth for privacy protection in the process of data sharing,identity privacy protection in the identity authentication process and dual privacy protection in the process of crowdsensing.The main research results are as follows:(1)A double blockchain based decentralized data sharing privacy protection model is proposed by discussing the privacy protection technology for data sharing.For the storage and retrieval requirements of shared data,a domain index-based Storage and Index Smart Contracts is proposed.All data is provided in both regular and encrypted storage modes.All providers can treat shared data is indexed based on metadata and published in a blockchain.to provide an efficient and secure automatic execution mechanism for data distribution.At the shared layer,a shared smart contract is proposed.The demander needs to submit a data analysis model to the data provider.The provider analyzes the data and returns the result.This solution can effectively guarantee the data provider's absolute control over the data.In order to protect the sharing rights and interests of data demanders,a reputation judgment mechanism based on subjective logic is established to provide the demanders with prior knowledge of each shared node.A blockchain-based arbitration mechanism is proposed.When the sharing parties question appeared,the system would select the arbitration alliance with delegate node election algorithm,and the arbitration alliance executes the arbitration selection algorithm to select the arbitration delegation node.The arbitration delegation node obtains the data from the data sharing parties and executes the results locally,and finally makes a fair and reasonable judgment.(2)A consortium blockchain based safe and efficient identity privacy protection scheme is proposed for identity authentication.Aiming at the communication security requirements between authenticators and authenticated parties identity authentication,a decentralized keyless signature model based on federated blockchain is proposed.The authenticated parties dynamically converts the communication key with a one-time password,and use timestamp to ensure the forward security of the key.In addition,the authenticated parties send the request through the blockchain network and receives the response for data transmission.The authenticators use the asymmetric encryption algorithm to generate the key and passes the blockchain consistency policies to verify identity with each other to ensure identity privacy.In the blockchain-based privacy model,a decentralized security consensus mechanism is designed to transform the blockchain into an automatic access control manager without any trusted third party participation.In order to reduce the consensus time and ensure the efficiency of the system operation,a consensus node selection algorithm is proposed,which reduces the time complexity of the consensus.Based on the smart grid application scenario,the proposed model was analyzed for security and performance.(3)A Blockchain based decentralized double privacy-preserving Incentive mechanism is proposed by studying the identity and data privacy protection technology in crowdsensing.A identity privacy protection scheme is designed for the perceived user based on the one-way aggregation signatures.A method of privacy protection based on homomorphic encryption is proposed.In addition,distributed consensus algorithm based on blockchain technology,introducing new role miners in addition to perceived users and task publishers.Miners use consensus algorithms to verify data quality and distribute reward.Because miners do not participate in the collection of sensory data,and all verification and operations are completed through the blockchain network,thus effectively ensuring the reliability of verification and the fairness of reward distribution.