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. 21, 2012
Filed:
Nov. 30, 2007
Dai Watanabe, Kawasaki, JP;
Hirotaka Yoshida, Yokohama, JP;
Dai Watanabe, Kawasaki, JP;
Hirotaka Yoshida, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A pseudorandom number generator reduced in size while maintaining high security is disclosed. The generator has a state storage unit of 2 blocks (n bits per block) and a buffer of plurality of blocks, and mixes their contents to obtain a random number sequence. The mixing is done by a nonlinear transformation unit for inputting the stored content of the buffer to output data of the same size as the input data, a first linear transformation unit for inputting the content of the state storage unit and the output of the nonlinear transformation unit to store an output into the state storage unit, and a second linear transformation unit for inputting the stored content of the buffer and the stored content of the state storage unit to store an output into the buffer. The mixed content of the state storage unit is output as a random number sequence.