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:
Oct. 08, 2013
Filed:
Jun. 08, 2012
Jun Furukawa, Tokyo, JP;
Kazue Sako, Tokyo, JP;
Jun Furukawa, Tokyo, JP;
Kazue Sako, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
Each participant apparatus () encrypts a plaintext by using a secret key of secret key cryptography, encrypts the encryption key by a public key, and sends the plaintext and public key to a substitution/decryption apparatus (). With this processing, the limitation on the length of a ciphertext to be processed can be eliminated. In this invention, a verifiable proof text using a public key by each substitution/decryption apparatus is verified by a verification apparatus () by using the public key. If one of a plurality of organizations to decrypt and shuffle ciphertexts has not correctly executed the operation, a third party can specify it and prove that the specified organization is unauthorized.