| 摘要 |
When a client reproduces a content, attribute information is read from the header of the content data corresponding to the content ID specified by the user. When the attribute information which has been read satisfies the attribute condition described in the license stored in the storage unit, encrypted content data is decrypted and output. After delivering a content, for example, by issuing a license having an attribute condition specifying a release date and artist, it is possible to sell a best version and a collection without creating a new content. If a license having a particular subscription ID as the attribute condition is defined, a user having the license can use a newly released content having the subscription ID without purchasing an additional license. |
