05479508 is referenced by 35 patents and cites 4 patents.

A method of operating a cable system having premium channel encoders and dedicated smart pay per view encoders, each associated with an individual channel. The pay per view encoders are provided with the addresses of certain subscriber stations that have been approved to decode pay per view events on the associated channels. These certain subscriber stations are addressed on a priority basis by the pay per view encoder handling the pay per view event to set their authorization memories to decode the pay per view event. The authorization memories are updated by RAM groups of five program tags. All of the PPV encoders are assigned to the same RAM group so that in updating authorization memories, the authorization of a subscriber station memory for another pay per view event is not altered. The authorization process is rapidly accomplished and is repeated for a period of time after commencement of the pay per view event. The certain subscriber stations are immediately deauthorized by the same pay per view encoder at the end of the pay per view event.

Title
Method of operating a pay per view television system
Application Number
7/703986
Publication Number
5479508
Application Date
May 22, 1991
Publication Date
December 26, 1995
Inventor
Larry K Moreland
McHenry
IL, US
Caitlin B Bestler
Chicago
IL, US
Assignee
Zenith Electronics
IL, US
IPC
H04N 7/167
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