Signcryption

From Wikipedia, the free encyclopedia

In cryptography, signcryption is a public key cryptosystem that was designed to both digitally sign and encrypt a message simultaneously. Therefor, signcryption implementions are meant to be secure, but also more efficient than traditional systems. Traditional systems, such as PGP, are used to first sign and then encrypt a message when both authenticity and secrecy are desired. Depending upon the cryptosystems used, signcryption can be between 50%-90% more efficient. Since the technology of signcryption was only recently developed, the level of security provided by it is unproven. It has not yet stood up to many years of cryptanalysis as older, more traditional, cryptosystem have.

Signcryption was invented by Yuliang Zheng in 1996. It is patent protected in Australia (AUS Patent #721497) and the United States (US Patent #6,396,928).

[edit] References

Y. Zheng, Digital Signcryption or How to Achieve Cost(Signature & Encryption) << Cost(Signature) + Cost(Encryption), Advances in Cryptology -- Crypto'97, Lecture Notes in Computer Science, Vol. 1294, pp. 165-179, Springer-Verlag, 1997.
Y. Zheng, Signcryption and Its Applications in Efficient Public Key Solutions, Proceedings of 1997 Information Security Workshop (ISW'97), Lecture Notes in Computer Science, Vol.1397, pp.291-312, Springer-Verlag, 1998.
F. Bao and R. H. Deng, A Signcryption Scheme with Signature Directly Verifiable by Public Key, Public Key Cryptography (PKC'98), LNCS 1431, pp. 55-59. Springer-Verlag, 1998.