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:
Aug. 22, 2000
Filed:
Feb. 11, 1998
Hugo Mario Krawczyk, Haifa, IL;
Tal D Rabin, Riverdale, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method for providing a digital signature, 'chameleon signatures', which provide the signer of a digital signature exclusive control to disclose the contents of the signed information to third parties. The signatures are closely related to 'undeniable signatures', but allow for simpler and more efficient realizations. The method is essentially non-interactive requiring no communication between sender and receiver and do not involve the design and complexity of zero knowledge proofs on which traditional undeniable signatures are based. The method employs a combination of standard digital signing methods with a unique hash functions. These hash functions are characterized by the non-standard property of being collision resistant for the signer but collision tractable for the recipient.