| 摘要 |
PROBLEM TO BE SOLVED: To achieve proper transmission control considering content of an attached file which is encrypted, to reduce a risk of information leakage.SOLUTION: If a password is applied to a file attached to a received electronic mail (namely, the file is encrypted), a mail in which a password for viewing the file is described is extracted, the password is used to decode the file, to apply rules of transmission control. An electronic mail to be transmitted actually is an electronic mail attached with a file having a password.SELECTED DRAWING: Figure 1 |
