High security pay television system
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Mar 6, 1990
Issued Date -
N/A
app pub date -
Sep 22, 1987
filing date -
Oct 12, 1984
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A high security pay television system is provided in which subscribers are provided with a decoder and with periodically changed removable memory modules. The decoder only functions to properly descramble the scrambled broadcast signal when a changeable system-wide code is available in the decoder. The code can either be carried in the memory module, or an internal code unique to the decoder and resident in the decoder can be combined with a external code in the removable memory module, and also unique to that decoder, to generate the common systemwide system code. Program viewership is written on the removable memory module. The removable memory module is provided with a pre-written limit of program viewing authorization so that when the limit is reached, further viewing is not possible.
First Claim
Family
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