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. 10, 2012
Filed:
Sep. 04, 2007
Yasuo Hatano, Yokohama, JP;
Kunihiko Miyazaki, Yokohama, JP;
Kenji Matsumoto, Yokohama, JP;
Yoji Shimizu, Tokyo, JP;
Yasuo Hatano, Yokohama, JP;
Kunihiko Miyazaki, Yokohama, JP;
Kenji Matsumoto, Yokohama, JP;
Yoji Shimizu, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An encryption processing part of a controller of each of user devices specifies components of content as encryption target parts, creates an encryption key creation key by reading out a public key, for each of the encryption target parts, of a second user who is allowed to view the encryption target part, raising a secret key of an administrator of the content data to the power of the public key thus read out, and calculating a remainder, encrypts random numbers each corresponding to each of the encryption target parts by using the encryption key creation key, creates an encryption key for each of the encryption target parts, and encrypts, by using the encryption key created for each of the encryption target parts, each of the encryption target parts corresponding to the encryption key.