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:
Jan. 31, 2017
Filed:
Oct. 03, 2012
Kddi Corporation, Tokyo, JP;
KDDI Corporation, Tokyo, JP;
Abstract
A non-linear processor, which subjects an input value from a feedback shift register storing an internal state of a stream cipher to non-linear processing to output a key stream, is connected to internal registers, which store output values from a non-linear substitution circuit which subjects the input value to non-linear substitution processing. The non-linear processor is provided with an exclusive-OR unit, which is at an input end of each of the internal registers and carries out an operation of a random number generated from part of values stored in the feedback shift register and the output value of the non-linear substitution circuit to mask the output value of the non-linear substitution circuit, and another exclusive-OR unit, which is provided at an output end of the internal register and performs an operation to unmask the value stored in the internal register.