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:
Sep. 20, 2022
Filed:
Jan. 16, 2019
Nippon Telegraph and Telephone Corporation, Chiyoda-ku, JP;
Tetsutaro Kobayashi, Musashino, JP;
Yuto Kawahara, Musashino, JP;
Hitoshi Fuji, Musashino, JP;
Reo Yoshida, Musashino, JP;
Kazuki Yoneyama, Hitachi, JP;
NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Chiyoda-ku, JP;
Abstract
A communication device includes a signature encryption unit that encrypts input information with a secret key and transmits the information to a server device if the communication device belongs to a group, and a signature decryption unit that downloads, from the server device, encrypted n−1 pieces of the input information transmitted from other communication devices and decrypts the encrypted n−1 pieces of input information with the secret key if the communication device belongs to a group. The communication device transmits session key generation information to the server device via the signature encryption unit, generates a session key using n−1 pieces of session key generation information acquired via the signature decryption unit and session key generation information of the communication device, transmits a cipher text encrypted with the session key via the signature encryption unit to the server device, and decrypts n−1 cipher texts acquired via the signature decryption unit with the session key.