We construct an Attribute-Based Encryption (ABE) scheme that allows a user's private key to be expressed in terms of any access formula over attributes. Previous ABE schemes were limited to expressing only monotonic access structures. We provide a proof of security for our scheme based on the Decisional Bilinear Diffie-Hellman (BDH) assumption. Furthermore, the performance of our new scheme compares favorably with existing, less-expressive schemes.
In REF , Ostrovsky et al. construct a KP-ABE scheme which allows a user's private key can be expressed in terms of any access formula over attributes.
Attribute-based encryption with non-monotonic access structures
CCS '07
Computer Science