| 摘要 |
PROBLEM TO BE SOLVED: To provide high-security pay broadcast service in which illegal viewing can be prevented. SOLUTION: In order to perform two-way communication with a receiver that receives broadcasted and distributed encrypted content information, individual control information for partially or entirely updating control information connected to a relevant receiver required for selecting content information viewable in the receiver and stored in the receiver is transmitted to the receiver and until the reception of the individual control information is notified from the receiver to acknowledge that the control information of the receiver is updated, a former viewing contract corresponding to control information before being updated by the individual control information is continued. When the updating of the control information is acknowledged, the former viewing contract is modified into a new viewing contract corresponding to control information after being updated by the individual control information. COPYRIGHT: (C)2006,JPO&NCIPI |
