| 摘要 |
<P>PROBLEM TO BE SOLVED: To restrict use of various distributed contents by a simple method and to release the restriction. <P>SOLUTION: A client 30 requires contents (a music score) and a key file from a server 10 via a communication line 20. For requiring the key file, specific identification data are transmitted with the request to the server 10 and stored in a data memory 34. In response to the request, a Web server 11 transmits the contents stored in a database 13, and a key issue server 12 transmits the key file including the identification data. Without the key file, a viewer 32 allows display of the music score alone, however, the music score can be printed if the key file is used. The contents can be printed on condition that the identification data in the key file corresponds to those stored in the data memory 32. <P>COPYRIGHT: (C)2004,JPO |
