Privacy Preserving for Electronic Medical Record Sharing in Healthchain With Group Signature
Chaoyang Li, Bohao Jiang, Mianxiong Dong, Xiangjun Xin, Kaoru Ota
Abstract
Healthchain is a new solution for electronic medical record (EMR) management in the Internet of Medical Things, which avoids data island and information tampering problems by applying blockchain technology. However, some attacks are executed on the cryptographic algorithm to steal user privacy. This article focuses on the privacy security of system users and EMR data to explore a more efficient and secure signature algorithm. An EMR group verification model has been presented to establish a transaction verification mechanism for Healthchain. The EMR data are verified by the creating group to form a transaction in Healthchain, and the transaction data are verified by the system-maintaining nodes group to achieve network consensus. Then, a lattice-based group signature scheme (GSS) is proposed to strengthen the quantum security of the EMR group verification model. This scheme can provide secure verification for the EMR validation and support group members with free joining and revoking. Moreover, correctness analyses explain that this scheme is correct; security proofs prove that it satisfies anonymity, traceability, and nonframeability; the performance analyses show that the proposed model and the GSS scheme are at least 35% time consumption saving, with low key generation time costs and verification complexity than similar work.