| 摘要 |
The invention relates to a method for monitoring access to protected audiovisual content, wherein a message, including N rights verification messages (ECM1, ECM2, ) placed one inside the other and command messages i with 1 = i = N, is received. The command message i contains an ith access criterion (CA_Entrance) and the command rights verification message i+1 in encrypted form. The command message N includes an Nth access criterion (CA_Inside) and a protected audiovisual content decryption key (CW), itself encrypted. For the command message i, i initially taking the value 1, a test (351) is carried out to verify if rights associated with a device satisfy the ith access criterion. If testing positive for the i index, the instruction message i+1 is decrypted and a repetition of said test for index i+1 is requested. If testing positive for the N index, the protected audiovisual content decryption key (CW) is accessed (354). |
