| Electronic Health Records(EHRs)have been widely used in the medical system plat form.The Records contain the patient’s medical records,in which the hospital is the reco rd manager and the patient is the record owner.Currently,the ownership and manageme nt of electronic health records are mostly separated,which leads to the risk of privacy le akage and loss of electronic health records stored in the medical cloud at anytime and an ywhere.In order to solve this problem,it is imperative to find a safe and feasible privac y protection scheme.Blockchain technology has the characteristics of immutability,tracea bility and decentralization,which can play a key role in protecting the privacy of record s.It can adapt to the current complex medical environment.The main work and innovation of this thesis are as follows:(1)By means of electronic health records in different application scenarios,we orga nize a large number of blockchain related literature privacy protection scheme.We analy ze the feasibility of the cross-blockchain technology application in electronic health recor ds.The functional modules and participants of cross-chain environment are designed and analyzed.We propose a privacy architecture based on cross-blockchain.(2)We present a scheme about cross-blockchain based privacy-preserving data shari ng for electronic health records(CPDS).We briefly describe the specific process operatio n of cross-blockchain based on Wanchain and analyze the security of the scheme from th e attack type of the adversary.The design of locked account generation scheme realizes t he function of decentralization,and the scheme has the characteristics of low cost,simple structure and convenient storage.It reduces the hidden danger caused by key leakage to the system.The setting of one-time account system and the application of ring signature ensure the privacy of the whole transaction,which is the security guarantee for CPDS sc heme to realize cross-blockchain operation.In this thesis,the cross-blockchain technology is applied to the privacy protection of electronic health records.At present,there are four kinds of cross-blockchain technolog y,and we choose distributed private control technology from the analysis of performance and other characteristics.The technology controls the private keys of various assets thro ugh distributed nodes and maps the original chain assets to cross-blockchain.This ensure s that various assets are interconnected in the blockchain system.Wanchain is a represent ative technology of distributed private key control.Through the application of the Wanch ain technology,we have realized the safe sharing of patients’ electronic health records a mong different medical institutions.It improves the efficiency and accuracy of patient tre atment.It also plays an important role in promoting the development of medical field,an d realizes the transformation from hospital-centered to patient-centered. |
