In conventional Ciphertext-Policy Attribute-Based Encryption (CP-ABE), the access policy appears in plaintext form that might reveal confidential user information and violate privacy. CP-ABE with hidden policies hides all attributes, but computational burden increases due to attribute hiding. this paper, we present a Linear Secret Sharing Scheme (LSSS) structure scheme only sensitive rather tha...

Revocation is a vital open problem in almost every cryptosystem dealing with malicious behaviors. In ciphertext policy attribute based encryption, unlike traditional public key cryptosystem, different users may hold the same functional secret keys related with the same attribute set leading to additional difficulties in designing revocation mechanism. In this paper, we propose the ciphertext po...

In this paper we propose a new scheme for ciphertext-policy attribute-based encryption that allows outsourcing of computationally expensive encryption and decryption steps. The scheme constitutes an important building block for mobile applications where both the host and users use mobile devices with limited computational power. In the proposed scheme, during encryption the host involves a semi...

In the cloud right weight attribute encryption scheme based on multi-agency. Under existing cloud computing environment based on multi-agency access control scheme generally do not take into account the weights of the attributes that the status attributes are equal. But in real life, with the right to property values are meaningful. Each attribute in the system that served as different roles, t...

With the development of cloud computing, more and more users employ cloud-based personal health record (PHR) systems. The PHR is correlated with patient privacy, and thus research suggested to encrypt PHRs before outsourcing. Comparison-based encryption (CBE) was the first to realize time comparison in attribute-based access policy by means of the forward/backward derivation functions. However,...