The Research Of Blockchain Based Secure Medical Data Sharing And Auditing

With the rapid development of medical industry and Internet technology,and the rapid increase of electronic medical data,the demand for medical data sharing among different medical institutions is increasing.Most existing medical data sharing systems rely on trusted third parties to process and manage the data,so the management and use of the medical data are not transparent.There existing some problems such as abuse and disclosure of the medical data,and it is impossible to achieve effective supervision on the use of the medical data.Therefore,it is necessary to propose a secure and efficient medical data sharing scheme to realize data supervision in the process of data transmission.Blockchain technology can provide data transparency,tamper-proof and traceability,which can be applied to ensure the integrity and security of medical data,and be used for data audit and data accountability.Otherwise,decentralized characteristics of blockchain can solve the problem of single point of failure in traditional centralized medical system.Proxy re-encryption is an encryption technology secure transformation between ciphertexts.The data owner can grant re-encryption key to the proxy server for transforming the original ciphertext into the ciphertext encrypted by the authorized party’s key,which is suitable for the secure sharing of medical data.However,most of the proxy re-encryption scheme have large computational cost,which is difficult to meet the practical application requirements of the medical data sharing system.Driven by the actual demand,this paper designs an efficient proxy reencryption protocol and a medical data sharing scheme based on blockchain.1.This paper proposed an efficient proxy re-encryption protocol based on PKI system.In this scheme,we add the SM2 signature algorithm to ensure the integrity of data during the encryption process.The security of this protocol is formalized in the random oracle model,and is reduced to elliptic curve computational Diffie-Hellman difficulty problem and elliptic curve discrete logarithm problem.Compared with the existing work,the proposed scheme has a great advantage in computational cost and is suitable for the medical data sharing model.2.This paper combines the proposed proxy re-encryption scheme with the blockchain technology to design an auditable medical data sharing scheme.In this paper,we choose Hyperledger Fabric as the blockchain platform.We use two channels to record the authorization related information of medical data and log information respectively.The smart contract of blockchain can help us achieve medical data authorization,user authentication,medical data access control,data usage records,data use audit and other functions.3.In the simulation experiment,we use JPBC cryptographic algorithm library to implement the proposed proxy re-encryption scheme,and test the performance of the algorithms separately.In addition,we use Docker virtual technology to set up the Hyperledger Fabric blockchain network and deploy related smart contracts.In order to verify the practical feasibility of the scheme,we use Hyperledger caliper to benchmark the proposed medical data sharing system.The results of the experiments show that this scheme can balance security and computational cost,and has strong fault tolerance and scalability,which can support the practical medical data sharing requirements.