Research On Multi-level Role Based Audit Scheme In Medical Cloud Environment

With the development of medical cloud,medical institutions use cloud servers to store electronic health records(EHRs),which can effectively reduce local storage costs and simplify the storage management process.However,most existing access controls rely heavily on the assumption that cloud servers are trusted.In fact,once medical records are uploaded to the cloud,the owner will lose control of the data,and sensitive content may be accessed or even maliciously modified by unauthorized entities.Therefore,protecting the integrity of EHRs is crucial.For high security fields such as healthcare,many data objects can only be accessed by a small number of corresponding users or auditors.Therefore,the existing data integrity audit scheme is not applicable to EHRs with more access and audit authority requirements.For the confidentiality and integrity of electronic health records in the medical cloud storage environment,the details are as follows:(1)This paper proposes a real-time audit scheme based on multi-level roles(RTA-MLR).Firstly,based on the specificity and sensitivity of the data structure of shared electronic health records,this scheme adopts real-time audit and deterministic audit to improve audit accuracy;Secondly,in order to achieve fine-grained access control under privacy protection,multi-level key management technology is adopted.By using different keys,multi-level roles perform integrity audits of data based on different permissions;Then,in order to avoid single point of failure bottlenecks in centralized auditing,a shared key is distributed to expected users through access control polynomials within the user group,thereby achieving hierarchical data auditing;Finally,in order to achieve non repudiation of audit results,cloud servers provide users with time stamped receipts signed by both parties,enabling accountability traceability.In addition,the security analysis verifies that the proposed scheme is provably secure;The experimental results show that the proposed scheme reduces the cost of data encryption,decryption,audit,and signature computation,and achieves scalability with low storage overhead.(2)This article combines blockchain smart contract technology and Role Based Access Control(RBAC)model to propose a distributed and reliable multi-level role access control framework in a medical cloud environment.Traditional access control mechanisms cannot monitor user operations on cloud platforms,making them susceptible to IP spoofing and other operations that affect data integrity.To ensure data integrity on cloud platforms,access control mechanisms should ensure authentication,identification,and authorization.This framework consists of three smart contracts: Access Control Contract(AC),Delict Contract(DC),and Enroll Contract(EC).To demonstrate the feasibility of the proposed framework,an Ethereum blockchain system was constructed to implement these three types of smart contracts.At the end of this chapter,the performance advantages of the scheme were demonstrated through theoretical analysis and experimental verification.