CRYPTOGRAPHIC COMMUNICATION DEVICE, CRYPTOGRAPHIC COMMUNICATION TERMINAL, CRYPTOGRAPHIC COMMUNICATION METHOD, AND CRYPTOGRAPHIC COMMUNICATION PROGRAM

摘要

A cryptographic communication device (111) comprises a memory (155), a management unit (167), an encryption unit (168) and a data transmission unit (169). The encryption unit (168) acquires, upon each reception of an input of communication data, one of encryption keys stored in a buffer that is an internal area of the memory (155), uses the acquired encryption key to encrypt the communication data, thereby generating encrypted data, and deletes the acquired encryption key from the buffer. The data transmission unit (169) transmits the encrypted data generated by the encryption unit (168), thereby performing a cryptographic communication. While the cryptographic communication performed by the data transmission unit (169) continues, the management unit (167) adds new encryption keys to the buffer in accordance with a rate at which the number of encryption keys in the buffer decreases.