CTA TR-4

The existing authentication algorithm described in ANSI/CEA-709.1 is now 25 years old. It uses a short, shared secret (only 48-bits) and a custom algorithm to perform authentication. Compared against todays cryptographic standards it cannot be considered a viable authentication algorithm for new designs. While it may be appropriate to implement it for backward compatibility reasons, it must not be considered as a part of an overall security system for ANSI/CEA-709.1 based systems.