By Paul A. Heimbach, Home Box Office, Inc.
Beginning this year, Home Box Office, Inc., w~ll scramble its HBO satellite-delivered programming. The scrambling system will provide highly reliable, trouble-free operation with minimal signal degradation due to the scrambling/descrambling process. Actual system parameters conform to HBO's rigorous Satellite Security System Design Target for performance, operation and security. A very high degree of signal protection is provided by digitally achieved combinations of encryption and scrambling techniques based on the National Bureau of Standards' Data Encryption Standard. The Data Encryption Standard is the foundation for highly sophisticated encryption and key distribution functions.
Each descrambler is addressable and fully controlled from the HBO origination facility. Operator attention to the descrambler is limited to the installation, initial settings of audio and video levels, and periodic maintenance.
This paper discusses the relevant technical details of the scrambling system.