05247575 is referenced by 864 patents and cites 6 patents.

An information distribution system provides information to a user, when the information corresponds to criteria individually selected by the user, and then charges the user only for the selected information thus provided. Encrypted information packages (IP's) are provided at the user site, via high and/or low density storage media and/or by broadcast transmission. The IP's selected by the user are decrypted and then printed or displayed for viewing by the user. The charges for the IP's thus displayed are accumulated within the user apparatus and periodically reported by telephone to the system's central accounting facility which issues encryption keys. The encryption keys, used to decrypt the IP's, are changed periodically. If the central accounting facility has not issued a new encryption key for a particular user station, the station is unable to retrieve information from the system when the key is changed.

Title
Information distribution system
Application Number
232706
Publication Number
5247575
Application Date
April 24, 1992
Publication Date
September 21, 1993
Inventor
Thomas H Lipscomb
145 E. 74th St., New York, 10021
NY, US
Peter J Sprague
249 Undermountain Rd., Lenox, 02140
MA, US
IPC
H04N 7/00
H04B 17/00
H04K 1/02
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