Research On Blockchain-Based Secure-Aware And Privacy-Preserving Personal Health Records Sharing

With the rapid development of information technologies and people’s increasing attention to personal health,personal health data are widely collected and stored as personal health records(PHRs).The sharing of PHRs has great significance to improve the accuracy of disease diagnosis and the scientificity of disease research.Due to the private feature of medical data,the privacy and security issues during PHR sharing have attracted wideranging concerns from academia and industry.In recent years,the cloud-based PHRs sharing scheme has brought a lot of convenience to people,but the centralization of the cloud inevitably poses threats to data security and privacy protection.Blockchain technology is a promising distributed technology with features such as decentralization,transparency,anonymity and non-tampering.It can address some intractable problems of cloud-based PHRs sharing.Motivated by these problems,this paper conducts a research on blockchain-based secure and privacy-preserving PHR shaing.The specific work is as follows:1)This paper proposes a cloud-assisted electronic medical record sharing with security and privacy protection via consortium blockchain.In this scheme,data requesters search desired the keywords which are uploaded by the data provider on the consortium blockchain,and obtain the matching results to get relevant information about shared PHRs.Then,data requesters send access request to the data owner and get the re-encryption ciphertext from cloud server after getting the data owner’s authorization.Data requester can decrypt PHR ciphertext using his/her private key.The scheme uses searchable encryption and conditional proxy re-encryption to achieve data security,privacy protection,and access control.In addition,the proof of authorization is designed as the consensus mechanism of the consortium blockchain to ensure the availability of the system.The security analysis shows that the proposed protocol can achieve the security goals including data confidentiality and integrity,access control,authentication,secure search,and privacy preservation.The performance evaluation on the Ethereum platform shows that the protocol has high computational efficiency.2)This paper presents a patient-centric PHR management and sharing scheme based on consortium blockchain with security and privacy preservation.In this scheme,interplanetary file system(IPFS)is used to store PHR ciphertext.Zero-knowledge proof provides evidence to verify the authenticity of keyword index on blockchain.The improved attribute-based encryption algorithm is integrated into the specially-designed smart contract to realize secure search,privacy preservation,and personalized access control.The security proof and analysis of the proposed scheme demonstrate that the designed protocol can meet the security goals including data security,secure search,collusion resistant privacy preservation,and personalized access control.This work is evaluated on real-word datasets and Hyperledger Fabric blockchain platform.The results show the performance of this scheme is superior to existing leading models.This paper studies the problem of PHR sharing in practical application scenarios,and realizes the secure sharing of PHR data,patient’s privacy protection and access control by combining blockchain technology and cryptography algorithm.This study effectively realized the safe storage and sharing of PHR data based on blockchain,and promoted the application of blockchain technology in the medical industry.