Research On Medical Health Data Sharing Scheme Using Blockchain

Aiming at the disadvantages of traditional medical data islands,medical health data sharing has become a general trend.Sharing can not only avoid a lot of waste of medical resources,but also improve the diagnosis efficiency of doctors.According to different sharing needs,sharing exists between different entities such as hospitals and R & D institutions.Completing the sharing operation usually goes through two stages of storage and sharing.In the storage stage,facing the massive growth of medical health data,the cloud server has become the first choice for its storage means with its powerful storage space and computing power.However,during the sharing phase,the following problems are faced: on the one hand,the shared entities do not need all the medical health data stored on the cloud server,they are only interested in specific medical health data;on the other hand,for security reasons,the health data stored on the cloud server is encrypted.For shared entities,obtaining the original medical health data is the ultimate goal.So how to securely distribute keys becomes a key issue.Furthermore,medical health data comes from patients who seek medical treatment,which is highly sensitive information.Patients are often reluctant to associate it with their true identity,that is,to achieve privacy protection.In view of the above practical needs,this paper proposes two safe and effective schemes.This paper studies symmetric searchable encryption technology,Shamir secret sharing technology and blockchain technology,and proposes a symmetric searchable medical data sharing scheme based on blockchain.R & D institutions collaborate to share medical health data to reduce costs is the motivation for this solution.This solution chooses to store the ciphertext of medical health data on a cloud server.R & D institutions can use the search credentials generated by symmetric searchable encryption to search for medical health data that they are interested in.The hospital completes the distribution of related keys through Shamir's secret sharing technology.The tamper-resistant characteristics of the blockchain can solve the problems of fraud and collusion caused by the distribution.Therefore,the smart contract is used to recover the keys,generate search credentials and complete decryption.This paper also researches ring signature technology and signcryption technology,and proposes a blockchain-based medical data ring signcryption scheme.Ensuring patient anonymity is themotivation for this solution.The blockchain has the characteristics of immutability,decentralization,transparency,and anonymity.Therefore,this solution uses the blockchain as a platform for medical treatment.However,according to actual needs,this paper makes some improvements to some features on the blockchain.On the one hand,the medical health data of the patient is encrypted using an elliptic curve-based encryption system and sent to a designated doctor,and only doctor can decrypt it.On the other hand,ring signatures are used to obfuscate the patient so that anyone,including the doctor,does not know who the real signed patient is.This paper improves the traditional way of signing first and then encrypting,and use ring signcryption to improve efficiency.