Patents by Inventor Hiroyuki Shizuya

Hiroyuki Shizuya has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Computer system, computer program, and addition method
    Patent number: 7434898
    Abstract: A computer system that makes it difficult to analyze the content of a calculation. In the computer system, a power operation unit performs the following operations using the input data “a” and “b”: ga=ga mod n, gb=gb mod n. Next, in the computer system, a multiplication unit performs the following calculation using ga and gb: gab=ga×gb mod n. Next, in the computer system, a discrete logarithm calculation unit calculates ci mod pi?1 to satisfy gab=gci mod pi (i=1, 2, 3, . . . , k). Next, in the computer system, a CRT unit calculates “c” to satisfy ci=c mod pi?1 (i=1, 2, 3, . . . , k) using the Chinese remainder theorem CRT.
    Type: Grant
    Filed: March 22, 2005
    Date of Patent: October 14, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yuichi Futa, Masami Yamamichi, legal representative, Satomi Yamamichi, legal representative, Keiko Yamamichi, legal representative, Motoji Ohmori, Hiroyuki Shizuya, Masahiro Mambo, Masato Yamamichi
  • Computer system, computer program, and addition method
    Publication number: 20070192622
    Abstract: A computer system that makes it difficult to analyze the content of a calculation. A power operation unit (262) performs the following operations using the input data “a” and “b”: ga=ga mod n, gb=gb mod n. Next, a multiplication unit (264) performs the following calculation using ga and gb: gab=ga×gb mod n. Next, a discrete logarithm calculation unit (266) calculates ci mod pi?1 to satisfy gab=gci mod pi (i=1, 2, 3, . . . ,k). Next, a CRT unit (267) calculates “c” to satisfy ci=c mod pi?1 (i=1, 2, 3, . . . ,k) using the Chinese remainder theorem CRT.
    Type: Application
    Filed: March 22, 2005
    Publication date: August 16, 2007
    Inventors: Yuichi Futa, Masato Yamamichi, Masami Yamamichi, Satomi Yamamichi, Keiko Yamamichi, Motoji Ohmori, Hiroyuki Shizuya, Masahiro Mambo