Patent ID: 6088798
Filing Date: 2000-07-11
Classification: H04L

Abstract:
A digital signature method for generating digital signature data for plaintext data M and checking a signature on the basis of the digital signature data, said digital signature method comprising the steps of:generating signature data satisfying public key Y=x.multidot.G including at least part of data on a point R of an elliptic curve E/Fq over a finite field Fq dependent on an arbitrarily generated random number k, base point G on the elliptic curve E/Fq, and an integer s dependent on the plaintext data M, secret key x, and the random number k; andchecking a signature by confirming that a relational equation defined as.+-.s.multidot.G=.+-.m.multidot.Y.+-.r.multidot.R over E/Fqis satisfied, whereins and R constitute the signature data, m is an integer dependent only on the plaintext data M, and r is an integer dependent on at least point R of the elliptic curve E/Fq.