A Simple and Effective Scheme of Ciphertext-Policy ABE

Abstract

Since more sensitive data are stored and shared on third-party sites, we may need a system capable of one-to-many communication and data encryption without knowing specific recipients. However, the traditional public key crypto system and broadcast encryption system can't solve both of the problems at the same time. Attribute-Based Encryption (ABE) offers both of the desired abilities. In this paper, we present a simple and effective scheme of Cipher text-Policy Attribute-Based Encryption (CP-ABE), where access structures are single AND gates on positive and negative attributes and the size of access structure is fixed. Our scheme can be proven chosen plaintext attack (CPA) secure under the decisional bilinear Diffie-Hellman (DBDH) assumption. In addition, we provide an implementation of our scheme and give performance measurements.