## CryptoDB

### Paper: A Variant of the Cramer-Shoup Cryptosystem for Groups with Unknwon Order

Authors: Stefan Lucks URL: http://eprint.iacr.org/2002/052 Search ePrint Search Google The Cramer-Shoup cryptosystem for groups of prime order is a practical public-key cryptosystem, provably secure in the standard model under standard assumptions. This paper extends the cryptosystem for groups of unknown order, namely the group of quadratic residues modulo a composed N. Two security results are: In the standard model, the scheme is provably secure if both the Decisional Diffie-Hellman assumption for QR_N *and* the factorisation assumption for N hold. In the random oracle model, the security of the scheme is provable by a quite efficient reduction.
##### BibTeX
@misc{eprint-2002-11576,
title={A Variant of the Cramer-Shoup Cryptosystem for Groups with Unknwon Order},
booktitle={IACR Eprint archive},
keywords={public-key cryptography / public-key cryptography, complexity theory, factoring assumption},
url={http://eprint.iacr.org/2002/052},
note={ lucks@th.informatik.uni-mannheim.de 11856 received 25 Apr 2002, last revised 18 Jun 2002},
author={Stefan Lucks},
year=2002
}