| 摘要 |
<P>PROBLEM TO BE SOLVED: To share contents respectively possessed by a plurality of users who have tokens of encrypted contents. <P>SOLUTION: A content reproducing system is constructed to have a means for requesting reproduction for requesting reproduction of the encrypted content and having the tokens, and a means for temporary reproduction for reproducing the encrypted content by responding to the request of reproducing the content. The means for temporary reproduction transmits a request for transmission of the token in a format which attaches a content identifier and digital signature, and the means for requesting reproduction temporarily returns the token to the means for temporary reproduction only when authentication of the digital signature succeeds. <P>COPYRIGHT: (C)2009,JPO&INPIT |
