This theory is applied to signcryption schemes with outsider security and an efficient, provably secure scheme, termed ECISS-KEM, is proposed. The theory is also applied to signature schemes, where it is shown that efficient hybrid signature schemes can never exist, and to signcryption schemes with insider security, where it is shown that several existing schemes can be considered hybrid signcryption schemes.
Category / Keywords: public-key cryptography / elliptic curve cryptosystem, hybrid cipher Date: received 25 Aug 2004, last revised 3 Jan 2009 Contact author: a dent at rhul ac uk Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation Note: 08/04 -- Minor errors corrected.<BR> 11/04 -- Proof errors corrected. Version: 20090103:171302 (All versions of this report) Short URL: ia.cr/2004/210