Conversions Among Several Classes of Predicate Encryption and Applications to ABE with Various Compactness Tradeoffs

Predicate encryption is an advanced form of public-key encryption that yield high flexibility in terms of access control. In the literature, many predicate encryption schemes have been proposed such as fuzzy-IBE, KP-ABE, CP-ABE, (doubly) spatial encryption (DSE), and ABE for arithmetic span programs. In this paper, we study relations among them and show that some of them are in fact equivalent by giving conversions among them. More specifically, our main contributions are as follows: − We show that monotonic, small universe KP-ABE (CP-ABE) with bounds on the size of attribute sets and span programs (or linear secret sharing matrix) can be converted into DSE. Furthermore, we show that DSE implies non-monotonic CP-ABE (and KP-ABE) with the same bounds on parameters. This implies that monotonic/non-monotonic KP/CP-ABE (with the bounds) and DSE are all equivalent in the sense that one implies another. − We also show that if we start from KP-ABE without bounds on the size of span pro...

• Type: Journal
• Year: 2015
• Where: ASIACRYPT
• Authors: Nuttapong Attrapadung, Goichiro Hanaoka, Shota Yamada 0001
• Keywords: ASIACRYPT 2015, Cryptology