| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve processing efficiency to encrypted music data. <P>SOLUTION: Key data are generated on the basis of use right information, key use purpose information is added to the key data to generate and temporarily store processing use information, control information and the key use purpose information included in the temporarily stored processing use information are compared, and data processing of the encrypted music data is performed by use of the key data according to an obtained comparison result. Thereby, the data processing of a plurality of pieces of the encrypted music data can be continuously and sequentially performed without waiting during the generation of the processing use information while generating the processing use information, and generation of inconsistency in the key data is nearly certainly avoided to avoid unnecessary execution of the data processing even when temporarily storing a plurality of pieces of the processing use information, so that the processing efficiency to the encrypted music data can be improved. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
