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:
Jun. 05, 2001
Filed:
Feb. 04, 1998
Don Coppersmith, Ossining, NY (US);
Rosario Gennaro, New York, NY (US);
Shai Halevi, Heartsdale, NY (US);
Charanjit S. Jutla, Elmsford, NY (US);
Stephen M. Matyas, Jr., Manassas, VA (US);
Mohammed Peyravian, Cary, NC (US);
David Robert Safford, Brewster, NY (US);
Nevenko Zunic, Wappingers Falls, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and apparatus for an advanced symmetric key cipher for encryption and decryption, using a block cipher algorithm. Different block sizes and key sizes are supported, and a different sub-key is used in each round. Encryption is computed using a variable number of rounds of mixing, permutation, and key-dependent substitution. Decryption uses a variable number of rounds of key-dependent inverse substitution, inverse permutation and inverse mixing. The variable length sub-keys are data-independent, and can be precomputed.