| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an encryption system for flexibly setting secrecy by setting the number of release keys corresponding to the secrecy of content. <P>SOLUTION: This content distribution system includes a key information generation means for generating key information for decoding the other content; a management information storage means for storing management information including the key information; a first encryption means (S303) for encrypting specific content on the basis of the key information of the management information; a reference information generation means for specifying one or more distributed content for reference which has been distributed before, and for generating reference information for reading one or more key information included in the content for reference; and a content preparation means (S304) for preparing content for distribution on the basis of the encrypted specific content and the reference information and other key information for decoding content to be distributed after the specific content. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
