PROCEDIMIENTO Y SISTEMA DE TRANSACCION POR TARJETA ELECTRONICA

LA INVENCION SE REFIERE A LAS TRANSACCIONES QUE UTILIZAN LAS TARJETAS INTELIGENTES. PARA PERMITIR PROTEGER SIMPLEMENTE OPERACIONES DE RECARGA DE MONTANTES PREPAGADOS EN TARJETAS CON MEMORIA, INCLUSO A PARTIR DE TERMINALES (10) DISPERSOS NO CONECTADOS A UN SERVIDOR CENTRAL (20), SE PROPONE SEGUN LA INVENCION, MEMORIZAR EN LA TARJETA CON MEMORIA (40) EL NUMERO DE OPERACIONES DE RECARGA EFECTUADAS. SE PREVE ENTONCES UN CONTADOR DE NUMERO DE RECARGAS; ESTE CONTADOR ESTA INCREMENTADO A CADA RECARGA PERO NO ES INCREMENTADO DURANTE OTRAS UTILIZACIONES DE LA TARJETA Y PARTICULARMENTE DURANTE LA UTILIZACION DE ESTA PARA CONSUMIR BIENES O SERVICIOS. LA INVENCION ES PARTICULARMENTE APLICABLE A LA GESTION COLECTIVA DE NUMEROSOS COMEDORES DE EMPRESA QUE TIENE VARIOS TERMINALES DE RECARGA A DISPOSICION DE LOS EMPLEADOS DE LA EMPRESA. PCT No. PCT/FR95/00151 Sec. 371 Date Jul. 30, 1996 Sec. 102(e) Date Jul. 30, 1996 PCT Filed Feb. 8, 1995 PCT Pub. No. WO95/22125 PCT Pub. Date Aug. 17, 1995A method of transaction replenishes a microprocessor-based card. The card computes a certificate of authenticity on the basis of data elements that it contains and that include the contents of its counter of the number of replenishment operations and its identification number. These data elements enable the card to verify its entitlement to be replenished. The card increments its counter of the number of replenishments. A replenishment terminal reads the identification number of the card and transmits to the card the data elements that pertain to it and that comprise the certificate of authenticity corresponding to it for the cycle in progress. The received certificate is compared with a certificate computed by the card. When the certificates are equal, the card accepts a replenishment of units.