| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a conditional access system capable of changing scramble systems of a video image and voice data and also excellent in tamper resistance. <P>SOLUTION: In the conditional access system with a transmitter and a receiving side terminal, a descrambling means, or a key encoding/decoding means is updated by update data transmitted from a conditional access update management means. <P>COPYRIGHT: (C)2008,JPO&INPIT |
