[RW13] New Constructions and Proof Methods for Large Universe Attribute-Based Encryption
Authors: Yannis Rouselakis, Brent Waters | Venue: CCS 2013 | Source
Abstract
In small-universe attribute-based encryption (ABE), all supported attributes must be enumerated and embedded into the public parameters at Setup time, limiting scalability. We introduce large-universe ABE constructions for both the key-policy (KP-ABE) and ciphertext-policy (CP-ABE) settings, where attributes can be arbitrary strings and no attribute pre-registration is needed. Our KP-ABE and CP-ABE constructions support any monotone Boolean formula as an access structure and achieve selective security under variants of the -linear assumption in bilinear groups. A key technical ingredient is a new proof technique that avoids the exponential blowup typically incurred when moving from small-universe to large-universe constructions, instead using random self-reduction and an information-theoretic argument.