PCS-ABE (t, n): a secure threshold multi authority CP-ABE scheme based efficient access control systems for cloud environment

Abstract

Cloud computing is a current phrase in marketing for an idea that has been recognized for years: Outsourcing. Cloud computing provides a large number of gratuities for each customer and enterprise agency. ‘Cloud model’ is more of a notion in which the data are hosted online and accessed at anytime-anywhere manner, on a pay-per-use model. However, the users may not fully trust the cloud service providers (CSPs) in that environment. So, it is hard to decide whether the cloud service provider (CSP) meets their expectations to provide the proper secrecy to users' shared data and privacy. Several access control schemes that allow, deny, or restrict users to have access to data have been proposed. Among these, the Attribute-Based Encryption (ABE) scheme has generally used to provide security efficiently in public managed cloud scheme storage. The earlier Attribute-Based Encryption (ABE) schemes have a single authority maintaining the whole attribute set and suffer from a single-point bottleneck problem. To resolve this issue, some Multi-Authority Attribute-Based Encryption (MA-ABE) schemes have proposed in which disjoint attribute sets are maintained separately, but the bottleneck problem still occurs. This paper involves multi-authority (MA) models, where multiple authorities mutually handle a uniform attribute set. It uses an efficient (t, n) threshold secret sharing scheme, in which n multiple authorities share the master key, and a legitimate user selects any t—out of n—authorities compute his/her secret_key. The results of security and performance analysis show that the proposed methodology is not only computationally secure whenever it is compromised by less than t—number of authorities, but still robust whenever at least t—number of authorities are active in the model. This paper uses an efficient encryption scheme to encrypt the plaintext message, which encrypts one byte at a time. It performs faster execution of encryption and reduces the hardware complexity.