| US 7,587,590 B2 | ||
| Encrypted communication apparatus | ||
| Keiki Yamada, Tokyo (Japan); and Tsuneo Sato, Tokyo (Japan) | ||
| Assigned to Mitsubishi Electric Corporation, Tokyo (Japan) | ||
| Appl. No. 10/451,826 PCT Filed Oct. 24, 2002, PCT No. PCT/JP02/11050 § 371(c)(1), (2), (4) Date Jun. 26, 2003, PCT Pub. No. WO03/039066, PCT Pub. Date May 08, 2003. |
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| Claims priority of application No. 2001-330190 (JP), filed on Oct. 29, 2001. | ||
| Prior Publication US 2004/0059908 A1, Mar. 25, 2004 | ||
| Int. Cl. H04L 9/36 (2006.01) | ||
| U.S. Cl. 713—161 [713/153; 380/1] | 12 Claims |
| 1. An encryption communication apparatus comprising:
(1) a communicating unit for sending and receiving communication data including at least a length field and a data field;
(2) an encryption processing unit for performing encryption processing or decryption processing of data in the data field
in the communication data;
(3) a length comparing unit for comparing a value of the length field in the communication data received and a minimum length
value stored in the apparatus in advance; and
(4) a controlling unit for controlling to perform the encryption processing or the decryption processing of dummy data which
are obtained by shifting the data in the data field or inverse data of the data in the data field when it is judged that the
value of the length field is less than the minimum length value or less than or equal to the minimum length value by comparing
in the length comparing unit in order to send a false message to an unauthorized user that the encryption processing or the
decryption processing is performed using data in the data field.
|