04501958 is referenced by 49 patents and cites 20 patents.

A system for verifying an operation in particular one that includes payment, the system comprising at least one terminal (11) and a plurality of portable objects (10) which may be coupled, preferably without contact, to the terminal. The terminal emits repeated interrogation messages suitable for triggering reading of the contents of a shift register (60, 190) in a portable object when said object is coupled thereto, only after a comparator has verified concordance between first validity data from the portable object and check data from the terminal. After processing, the terminal re-writes updated useful data in the register. Re-writing is only authorized after a comparator (240) has verified concordance between second validity data stored in the shift register with check data transmitted by the terminal into a register (220) of the portable object. The check data is produced by the terminal after decoding the validity data contained in the message derived from reading the portable object (10).

Verification system, for example for passing through a toll point
Application Number
Publication Number
Application Date
March 3, 1982
Publication Date
February 26, 1985
Michel M Gaucher
Le Mesnil Saint-Denis
Jean Pierre Glize
Labastide D'Armagnac
Herbert Dubno
Karl F Ross
Electronique Marcel Dassault
H04Q 1/30
View Original Source