| 摘要 |
The invention relates to a method for securing control words (CW) within a decoder (10) responsible for unscrambling digital content protected by those control words, comprising the following steps: - for each unscrambling unit (14) of said decoder, loading a pairing key (PK) referenced by an identifier (ID) associating it with an unscrambling unit into a directory (22), - receiving at least one encrypted control word referenced by an indication making it possible to identify the unscrambling unit for which it is intended, - decrypting the control word using a first key shared with a security module (30), - identifying, in the log, the pairing key whose identifier (ID) corresponds to the indication of intended use (D) associated with the control word, - encrypting that control word using that pairing key, - storing the control word in a log (15) in a chronological and referenced manner. |
