The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 04, 1997
Filed:
Aug. 17, 1994
Rainer A Rueppel, Wetzikon, CH;
Kaisa Nyberg, Vienna, AT;
R3 Security Engineering AG, Aathal, CH;
Abstract
A digital signature method based on the discrete logarithm problem is provided that allows message recovery. The message x is transformed according to the rule e=x g.sup.-r mod p, where r is a secret value generated by the signer. A value y is then calculated according to the rule y=r+s e mod q, where y is the signer's secret key. The signature of x consists of the pair (e,y). The verifier recovers the message x according to the rule x=g.sup.y k.sup.e mod p, where k is the signer's public key. The validation of x can be based on some redundancy contained in x. Alternatively, a conventional verification equation can be constructed by using the signature method together with a hash function H. In addition, a key agreement method based on the signature method is provided which establishes with a single transmission pass a shared secret key K between two parties A and B in an authenticated fashion.