Eecient Signcryption Schemes on Elliptic Curves

Signcryption is a new paradigm in public key cryptography. A remarkable property of a signcryption scheme is that it fulllls both the functions of public key encryption and digital signature, with a cost signiicantly smaller than that required by signature-then-encryption. The purposes of this paper are to demonstrate how to specify signcryption schemes on elliptic curves over nite elds, and to examine the eeciency of such schemes. Our analysis shows that when compared with signature-then-encryption on elliptic curves, signcryption on the curves represents a 58% saving in computational cost and a 40% saving in communication overhead.