Patent · US Expired

Antifraud method and device for a selective access system

US5006698A · kind A · utility

7Cited by
9References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 7, 1988
Grant dateApr 9, 1991
Priority date
Expiry dateJul 7, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG07F7/1083
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A method and apparatus for protecting a selective access system against fraudulent use of a magnetic card having a confidential card. Each cade (CM) is associated with a class corresponding to a zone of a memory (PROM). The number of classes is equal to the number of zones and is substantially less than the number of cards (CM) which may be presented. At each failure to input a confidential code, one of the bits is modified in the corresponding memory zone.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.