| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To carry out access control only with the presence/absence of a key without performing user authentication and to permit data browsing according to a disclosure level corresponding to a user's position and authority. <P>SOLUTION: Data for controlling access from the user is encrypted in common key cipher with the key M. The key M is encrypted by hidden vector encryption by setting a vector value according to the disclosure level corresponding to the user's position and authority, and the encrypted key M is added as header information to the encrypted data and stored. Using the key distributed beforehand corresponding to the user's position and authority, the header information is decoded to acquire the key M, and using the acquired key M, the encrypted data are decoded to browse the data. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
