Research On Medical Data Sharing Scheme Based On Blockchain

With the steady development of smart medical technology and the continuous expansion of medical scale,the medical field is gradually stepping into the digital era.Achieving medical data sharing not only avoids massive waste of medical resources,but also promotes medical technology innovation and improves the quality of medical services,which plays a huge role in achieving sustainable development in the medical field.The completion of sharing operations usually requires two phases: storage and sharing.In the storage phase,cloud servers are the first choice for healthcare organizations to store data due to their powerful performance in the face of the explosive growth of healthcare data.However,in the sharing phase,there are some problems: On the one hand,medical data stored in cloud servers is usually encrypted for security reasons.Although encryption can ensure the confidentiality of data,it is not conducive to subsequent data retrieval and sharing by users.On the other hand,privacy protection is very important for patients who provide medical health data.This is because patients do not want to disclose their private information to malicious users who do not have the right to share the data.In response to the above realistic needs,this paper proposes two secure and effective solutions.The main contributions are as follows:(1)This paper proposes a medical data sharing scheme based on blockchain and revocable attribute-based searchable encryption.The scheme uses searchable encryption technology to solve the problem of users retrieving data on the ciphertext domain;it uses attribute-based encryption technology to achieve fine-grained access control of user search privileges;it uses binary trees for attribute group key distribution to achieve efficient user and attribute revocation;and it uses the tamper-proof and traceability of blockchain technology to ensure the tamper-proof data and traceability of shared operation information.The results of security proof and performance analysis show that the scheme is secure and effective.(2)This paper proposes a medical data sharing scheme based on blockchain and policy hidden attribute-based searchable encryption.The scheme addresses the problem that traditional attributebased encryption may reveal private information by dividing attributes into two parts: attribute name and attribute value.The access policy represents only the attribute name explicitly,while the more sensitive attribute value is hidden in the ciphertext to ensure that malicious users who are not authorized to share data cannot know the specific attribute value.The solution also solves the problem that the fine-grained search permissions need to be updated in time due to changes in user attributes.The solution also supports multi-keyword searchable encryption,which improves the efficiency and accuracy of search.The results of security proof and performance analysis show that the scheme is secure and effective.