DIGITAL CONTENT DISTRIBUTION SYSTEM, RIGHT MANAGEMENT SERVER AND USER TERMINAL

摘要

In a right management server ( 100 ), a license data generation/updating unit ( 307 ) generates license data ( 900 ) including a use condition ( 503 ) for permitting a user to use a content based on a content use right ( 500 ) owned by the user. A subset use condition setting unit ( 308 ) sets a subset use condition ( 901 ) for temporarily invalidating the license data ( 900 ) in the license data ( 900 ). A communication unit ( 311 ) transmits the license data ( 900 ) in which the subset use condition ( 901 ) is set to the user terminal ( 110 ), and receives the license data ( 900 ) returned from the user terminal ( 110 ). Upon receipt of the invalidated license data ( 900 ), the license data generation/updating unit ( 307 ) cancels the invalidation of the license data ( 900 ) by updating the subset use condition ( 901 ).