| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a management system, an authentication server or the like, capable of improving security in a file security management system including a client device encrypting a file and/or using an encrypted file and an authentication server. <P>SOLUTION: A file former (client device 30a) sets and registers an use authority for permitting a file to be encrypted and a user thereof by use of an exclusive viewer 32. A user (client device 30b) which received the encrypted file receives the authentication by the authentication server 20 by use of the exclusive viewer 32, whereby the encrypted file can be decoded and used within the range of the use authority permitted to the user. Accordingly, since a key and the decoded file are never left in the user, the safety can be improved. Since the authentication server transmits a warning to the file former or the like when the authentication result is negative, a person involved can immediately investigate the cause. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
