Renewability
It is contemplated that an authorized participant in the authentication protocol may become compromised so as to expose the secret device keys it possesses for misuse by unauthorized parties. In consideration of this, each video receiver is issued a unique set of secret device keys, matched with a non-secret identifier (the KSV). Through a process defined in the HDCP Adopters License, the Digital Content Protection LLC may determine that a set of secret device keys has been compromised. If so, it places the corresponding KSVon a revocation list that the video transmitter checks during authentication. Other, authorized, receivers have different sets of secret device keys and, thus, are not affected by this revocation.
The video transmitter is required to manage system renewability messages (SRMs) carrying the KSV revocation list. These messages are delivered with content and must be checked when available. The validity of an SRM is established by verifying the integrity of its signature with the Digital Content Protection LLC public key, which is specified by the Digital Content Protection LLC.