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:
May. 12, 2009
Filed:
Oct. 28, 2004
Ming Zhang, San Jose, CA (US);
Awais Bin Nemat, Santa Clara, CA (US);
Ming Zhang, San Jose, CA (US);
Awais Bin Nemat, Santa Clara, CA (US);
Cisco Technology, Inc., San Jose, CA (US);
Abstract
Methods and systems for implementing a switch box (S-box) in a cryptographic application are described. An input to the S-box is converted from a Galois field representation GF(N) to a Galois subfield representation GF(N). The input is converted using a generating polynomial of the form x+Ax+B, where A and B are elements in GF(N) and where A has a value other than unity. The multiplicative inverse of the Galois subfield representation GF(N)is determined. The multiplicative inverse is converted back to the Galois field representation GF(N). An affine transformation of the multiplicative inverse is then performed.