Abstract
The Electronic Medical Record (EMR) management system currently used by healthcare institutions has security concerns for data sharing and access control. To address these issues, we have proposed a security and privacy management scheme for blockchain-based EMR called GAC-PSPR (Granular Access Control supporting Privilege Separation and Property Revocation). The GAC-PSPR scheme uses a dual chain structure of private blockchain and consortium blockchain. The technology of permission separation and property revocation ensures that data cannot be arbitrarily modified, thus solving the security problem of access control. Protect data privacy by protecting against quantum attacks with Number Theory Research Unit (NTRU) encryption. Besides, we have proposed a ring signature solution based on the lattice to address the issue of too large signatures and the key lengths that secures the sharing of EMR data. We provide extensive security analysis and performance analysis to demonstrate that the GAC-PSPR scheme is effective and secure.