| 摘要 |
PROBLEM TO BE SOLVED: To reduce an unnecessary operation and to maintain security by storing whether or not ciphering is executed for respective transmitted data, controlling the ciphering of data based on the stored propriety of ciphering and transmitting data which is ciphered or not ciphered. SOLUTION: A data storage part 17 is provided with a storage medium recording the transmission destination of an electronic mail and the telephone number and the address of a transmission source and storing them with information indicating whether security maintaining is required or not in data communication between the respective destinations and the transmission source. The storage area of the electronic mail, which is provided in the storage medium, is divided into a secret box and a regular mail box. In the transmission/ reception processing of the electronic mail to an opposite party whose security is to be maintained, the destination and the presence or absence of the necessity of security are previously mentioned in address data and they are security- registered. Thus, the electronic mail is automatically ciphered in transmitting it and it is accumulated in the secret box upon reception. |
