The videocipherTM | scrambling system

The VideoCipher^{TM I scrambling system is a very secure, very high quality system for satellite transmission of stereo audio and video program material. Stereo audio is transmitted digitally and is encrypted bit-by-bit, rendering the scrambled format completely unintelligible. Video is scrambled via a time-shuffling algorithm under control of a cryptographic keystream, which ensures that the scrambled picture is totally unrecognizable. Security is based on the National Bureau of Standards´ DES encryption standard, which is employed to generate keystream for encryption and scrambling. Control of the VideoCipher I system is also embedded in the scrambled waveform, with a tiering hierarchy that allows rapid control of millions of Descramblers. Overall, the system performs to an extremely rigorous set of performance specifications, with over 85 dB of audio dynamic range and 57 dB of weighted video signal-to-noise ratio.}