04471216 is referenced by 141 patents and cites 5 patents.

The user has a credit card incorporating electronic devices and/or circuits. The facility which is to be protected has an electronic device and/or circuit analogous to that of the credit card. The devices of the credit card and of the facility contain in their respective memories a secret code S, an identification code I.sub.n, and a program p. The facility which is to be protected has available a generator of a random code E which is transmitted into each of the devices when a request for access is made. The devices within the card and the facility each calculate the function R=p(S, E, I.sub.n), and a comparator situated in the facility which is to be protected compares the functions supplied by each of the devices to allow or deny access of the person to the said facility.

System and process for identification of persons requesting access to particular facilities
Application Number
Publication Number
Application Date
October 27, 1980
Publication Date
September 11, 1984
Robert J L Herve
Kerkam Stowell Kondracki & Clarke
Compagnie Internationale pour l Informatique CII Honeywell Bull
G06K 19/06
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