QC-PRE: quorum controlled proxy re-encryption scheme for access control enforcement delegation of outsourced data
Shravani Mahesh Patil, B. Purushothama · International Journal of Information and Computer Security · 2022
Proxy re-encryption is used to delegate the task of providing access control to the outsourced data on a cloud storage server. However, the straightforward application of proxy re-encryption requires the cloud storage server to be trusted. The cloud storage servers are however, often, honest-but-curious or untrusted. Towards solving the problem of access control enforcement delegation of outsourced data, we design a quorum controlled proxy re-encryption scheme. We show that, using the proposed scheme, task of enforcing access control is delegated to a set of proxies, such that a quorum of proxies should come together to enforce access control. By distributing trust among multiple proxies, single point of trust is eliminated, and the system is made fault tolerant. We prove the IND-CPA security of the proposed scheme under the DBDHI assumption and show that it satisfies most of the desirable properties of a proxy re-encryption scheme thus outperforming the existing schemes.