Verifiable outsourcing EMRs scheme with attribute-based encryption in cloud-edge environments

Abstract

With emerging of cloud and edge computing, it is popular to store Electronic Medical Records (EMRs) on a remote cloud. Furthermore, to share the EMRs stored in the cloud, attribute-based encryption (ABE) can provide a fine-grained access control strategy. However, in ABE, the finer the access control is, the bigger the number of required attributes is. Accordingly, it requires the higher computation costs. In this paper, to reduce the burden of patients, we first present a verifiable outsourced ABE scheme with the help of edge servers and fog nodes, in which edge servers are fully responsible for the encryption of ABE while fog nodes assist data users to perform the corresponding decryption. Furthermore, to protect the privacy of data owner, we introduced the proxy re-encryption algorithms, which still can achieve dual access control for EMRs. What's more, to detect the honesty of edge servers and the cloud, we adopt an aggregated digital signature to guarantee the correctness of the EMRs initially encrypted by data owner. The experimental results and security proofs show that our scheme has higher computational efficiency and achieves more fine-grained access control.