A Strong and Testable Threshold Multi-Authority Access Regulation System in Public Cloud Storage

Abstract

Attribute-based Cryptography (ABC) is found to be a promising cryptanalytic conducting tool to ensure information owners’ direct management over their information in public cloud storage. Traditional ABC schemes involve just one authority to keep up the entire attribute set, which might bring a single-point bottleneck on each security and performance. Afterwards, some multi-authority schemes are projected, within which multiple authorities one by one maintain disjoint attribute subsets. However, the single-point bottleneck downside remains unsolved. In this paper, from another perspective, we tend to conduct a threshold multi-authority CP-ABC access management theme for public cloud storage, named TMACS, within which multiple authorities collectively manage a consistent attribute set. In TMACS, taking advantage of (t; n) threshold secret sharing, the master key is often shared among multiple authorities, and a legal user will generate his/her secret key by interacting with any t authorities. Security and performance analysis results show that TMACS isn't solely verifiable secure when less than t authorities are compromised, but additionally strong when no less than t authorities are within the system. Moreover, by expeditiously combining the normal multi-authority theme with TMACS, we tend to construct a hybrid one, that satisfies the situation of attributes returning from completely different authorities as well as achieving security and system-level robustness.