Patent ID: 7587590
Filing Date: 2009-09-08
Classification: H04L

Abstract:
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.