Study On Blockchain And Proxy Re-encryption Based Secure Data Sharing Method In Internet Of Things

The booming development of Internet of Things(Io T)technology has brought great convenience and help to people's life.The GSMA claimed that there will be 25 billion Io T devices worldwide by 2025.A large amount of data collected by Io T devices contains important information resources,which can be mined and analyzed by technology to produce meaningful information for human's production and life.Io T data is generally stored in third-party cloud services.The cloud service providers provide data storage and sharing services.Due to the centralization characteristic of traditional third-party cloud service providers and users' distrust of cloud service providers,the Io T data sharing has the following security problems: First,the integrity of Io T data is easily damaged by external malicious attacks or misoperation of cloud service providers;Second,it is difficult to balance the confidentiality and efficiency of Io T data sharing.If users upload plaintext data,they will lose the ability to control the data and then the data might be abused.If users upload ciphertext data,it is not convenient for them to share ciphertext data with others.To solve the above problems,this paper proposes a proxy re-encryption and blockchain based secure Io T data sharing method,the major work is as follows.First,the method uses an Identity-based Proxy Re-encryption scheme to reduce the certificate management overhead caused by traditional proxy re-encryption algorithms.What's more,the ciphertext Io T data is converted once to realized secure sharing in ciphertext state,and the sharing efficiency is improved;Second,based on the decentralized and the non-tamperable characteristic of blockchain technology,the paper uses the Tendemint platform to realize the integrity protection of the data in the sharing process;Thirdly,in response to the problem of the reduction of consensus efficiency caused by the malicious behavior of the consensus nodes,a credit scoringbased consensus mechanism improvement method is proposed.Establish a credit scoring mechanism for the consensus nodes of the Tendermint platform,and implement different degrees of rewards and punishments according to the behavior of the nodes to achieve behavioral incentives.This paper conducts simulation experiments on the proposed data sharing method to verify the feasibility of the method.The paper performs proxy re-encryption and blockchain performance tests on simulation applications.The results show that the proxy re-encryption algorithm used in this method is more efficient,and the Tendermint platform used has higher read and write performance.Finally,the improved method of the consensus mechanism is verified,which proves that the credit scoring algorithm can effectively reduce the impact of the decrease in consensus efficiency caused by the malicious behavior of nodes.