| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent information leakage by web-based e-mail to be transmitted to an external network by using data of web-based e-mail of the same thread as a common key in a chain-reaction manner. <P>SOLUTION: When transmitting new web-based e-mail that is not a return e-mail, root e-mail becoming common key data for encrypting and decrypting the new web-based e-mail is generated, and the new web-based e-mail is encrypted using the common key data obtained from the root e-mail. When transmitting web-based e-mail being a return e-mail, the web-based e-mail being a return e-mail is encrypted using common key data obtained from return source e-mail, the web-based e-mail encrypted and transmitted from the outside is decrypted in a chain-reaction manner using root e-mail in an encrypted e-mail thread and the common key data included in the web-based e-mail. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
