| 摘要 |
This invention concerns a method for processing control messages from an aggregation of control messages meant to access encrypted content received as a flow by a multimedia unit. These messages comprise at least a discrimination parameter with a value that is different for any two consecutive messages from the flow as well as information to access encrypted content. This method comprises the reception steps for the current control message, reading of the discrimination parameter of the current control message, research into the memory, of the discrimination parameter for the message processed previously to the current message, of comparison of the discrimination parameter of the current message with the discrimination parameter of the previously processed message, and the blocking by a filter of the said current control message if the comparison step shows that the discrimination parameter of the current message is identical to the discrimination parameter previously processed. The method is characterized by the fact that the discrimination parameter is different for each message of a given subgroup of an ordered group of control messages, this subgroup containing at least three control messages and, at the most, all the control messages from among all the messages, so that, during the filtering step, the current message and the previously processed message can be non-consecutive in the ordered subgroup of messages. |
