Those interested in predicate encryption might also enjoy Group Authentication Using The Naccache-Stern Public-Key Cryptosystem
http://arxiv.org/abs/cs/0307059 which takes a different approach and handles negation. A group authentication protocol authenticates pre-defined groups of individuals such that: - No individual is identified - No knowledge of which groups can be successfully authenticated is known to the verifier - No sensitive data is exposed The paper presents a group authentication protocol based on splitting the private keys of the Naccache-Stern public-key cryptosystem in such a way that the Boolean expression defining the authenticable groups is implicit in the split Shamelessly, Scott --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]
