04658292 is referenced by 97 patents and cites 5 patents.

An enciphering key distribution system comprises a transmitter having an address generator for generating the addresses of those subscribers to which a first enciphered TV signal is to be distributed. An enciphering generator generates a second enciphering, in response to the individual addresses, on a one-to-one correspondence with the individual subscribers. A multiplier produces a product which is associated with all the subscribers. An adder adds the first enciphered signal to the product. The system also comprises a receiver having a divider for dividing the signal transmitted from the transmitter by one of the second encipherings on a basis which is assigned to the particular subscriber or receiver.

Title
Enciphering key distribution system for subscription TV broadcast or catv system
Application Number
6/489243
Publication Number
4658292
Application Date
April 27, 1983
Publication Date
April 14, 1987
Inventor
Katsuhiro Nakamura
Tokyo
JP
Eiji Okamoto
Tokyo
JP
Agent
Laff Whitesel Conte & Saret
Assignee
NEC Corporation
JP
IPC
H04L 9/00
H04N 7/167
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