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, 2015
Filed:
Mar. 17, 2011
Takeshi Kawabata, Kanagawa, JP;
Hideo Shimizu, Kanagawa, JP;
Takeshi Kawabata, Kanagawa, JP;
Hideo Shimizu, Kanagawa, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
According to one embodiment, an encryption device includes a storage unit, an input unit, first to fourth partial encryption units, a generation unit, and an output unit. The first partial encryption unit calculates first intermediate data from input plain data to store in the storage unit. The generation unit generates a round key, which is used in calculations for the first intermediate data and N-th intermediate data, from the secret key. The second partial encryption unit calculates (i+1)th intermediate data from i-th intermediate data (i is smaller than N) and the round key to store in the storage unit. The third partial encryption unit performs an arithmetic operation including predetermined conversion for mixing the N-th intermediate data, and calculates (N+1)th intermediate data to store in the storage unit. The fourth partial encryption unit obtains encrypted data by performing an arithmetic operation including inverse conversion of the conversion on the (N+1)th intermediate data.