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:
Nov. 10, 2015
Filed:
Dec. 16, 2011
Katsuyuki Takashima, Tokyo, JP;
Tatsuaki Okamoto, Tokyo, JP;
Katsuyuki Takashima, Tokyo, JP;
Tatsuaki Okamoto, Tokyo, JP;
Mitsubishi Electric Corporation, Tokyo, JP;
NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo, JP;
Abstract
A decentralized multi-authority functional encryption according to which the security of the whole system does not depend on a single party. Among a plurality of key generation devices, arbitrary one key generation device generates gparam, and each key generation device generates an authority public key and an authority secret key based on gparam. At least some key generation devices among the plurality of key generation devices generate a part of a decryption key of the user based on the authority secret key ask. The user forms one decryption by putting together the decryption keys generated by at least some of the key generation devices, and decrypts a ciphertext.