Research And Implementation Of Security Sharing Technology In Electronic Medical Record

In the health care system,a patient’s medical record（including prescriptions,lab slips,test results,MRI images）is a valuable data asset.In recent years,with the continuous development of the Internet of Things,big data and cloud storage,the capacity of medical data has grown exponentially.The development of medical informatization is the trend of The Times,but at the same time,due to the independent data resources cannot be Shared between medical institutions,medical and other traditional industries to IT the acceptance of the new technology is not high,how to guarantee the safety and reliability of data,medical privacy data not been tampered with and leak,is currently the medical informatization development needs to solve the problem.The main work of this paper is to use attribute-based encryption technology and data integrity verification technology to achieve secure sharing of electronic medical records on the basis of blockchain architecture,which can be divided into the following three parts:（1）A CP-ABE scheme based on OBDD access structure is proposed.In this scheme,by introducing Huffman attribute tree,the system attributes are stored in the form of Huffman coding,and the weighted path is used as the user attribute identification,which saves a lot of storage space,improves the search efficiency,and facilitates the timely revocation of user attributes;in the decryption stage,the cloud service provider and the data owner verify whether the user attribute group meets the access policy in turn;at the same time,the party The scheme is based on the access structure of ordered binary decision diagram（OBDD）,which can effectively improve the expressiveness of access policies.Compared with the traditional attribute based encryption scheme,the scheme has the characteristics of anti forgery attack,attribute revocation and white box traceability,and is proved to be secure under the chosen plaintext attack.（2）A data integrity verification scheme of shared electronic medical records based on red black tree is proposed.Firstly,the specific information of doctor-patient data is stored on the cloud server CSP.At the same time,through the introduction of parallel chain architecture,the doctor-patient integrity verification information is respectively stored on the patient chain and the doctor chain in different attribute based encryption ways,so as to realize the exclusive use of the special chain.Secondly,the data integrity verification scheme and dynamic data update scheme based on red black tree are constructed,so as to ensure the safety of insertion In the case of more deletions,the high performance of the algorithm is still maintained.Security analysis shows that the scheme not only has public verifiability,can effectively resist the cloud server forgery attack,but also can protect the privacy of user and patient information,and has high integrity verification efficiency and data update efficiency.（3）This paper designs and implements a shared electronic medical record system based on blockchain.Through the implementation and analysis of the CP-ABE scheme based on OBDD access structure and the data integrity verification scheme based on red black tree,it shows that the scheme has higher efficiency and security,and meets the requirements of practical application.The system is mainly divided into user management module and server design module,and is based on Java User client,trusted authorization center server and cloud server are designed.System experiments show that this scheme can realize data sharing between different regions and different users on the basis of ensuring user privacy.