| 摘要 |
PROBLEM TO BE SOLVED: To provide a system and a method for safely recording a broadcast media program for the playback use which will be limited later. SOLUTION: There is provided a method and an apparatus for storing and obtaining a program element for the later replay. This method comprises the steps of containing a first CW encryption key 509 and a control data to an access control information, receiving an encryption access control information and a program element 503 encrypted depending on the first CW encryption key 509, generating the first CW encryption key 509 by decoding the received access control information, decoding the program element 503 using the first CW encryption key 509, re-encrypting the program element depending on a second encryption CP key 516, encrypting the second encryption key depending on a third encryption CAM key 520 to generate a fourth encryption CP key 524, and providing the re-encrypted program element 518 and the fourth encryption CP key 524 for the storage purpose. |
