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. 06, 2001
Filed:
Feb. 23, 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);
Luke James O'Connor, Adliswil, CH;
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
The present invention provides a technique, system, and computer program for a symmetric key block cipher. Variable block sizes and key sizes are supported, as well as a variable number of rounds. The cipher uses multiple stages of processing, where the stages have different structures and different subround functions, to provide excellent resistance to both linear and differential attacks. Feistel Type-1 and Type-3 are both used, each during different stages. The number of rounds may vary among stages. Subkeys are used in some, but not all, stages. The variable-length keys can be precomputed. A novel manner of using data-dependent rotation in a cipher is defined.