Method and device for the checking of the number of access attempts to an electronic store, notably that of an integrated circuit of an object such as a credit card or a buyer's card

• US 4,439,670 A
• Filed: 11/10/1982
• Issued: 03/27/1984
• Est. Priority Date: 11/30/1979
• Status: Expired due to Fees

• Current Assignee: Electronique Marcel Dassault
• Original Assignee: Electronique Marcel Dassault
• Inventors: Basset, Jean-Claude, Belenfant, Guy
• Primary Examiner(s): Pitts, Harold I.
• Application Number:
  US06/440,697
• Time in Patent Office: 503 Days
• Field of Search: 235/380, 235/381, 235/382, 235/382.5, 340/543, 340/825.32
• US Class Current: 235/382
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G07F 7/10 together with a coded signal , e.g. in the form of personal identification information, like personal identification number [PIN] or biometric data
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: G07F 7/1083 Counting of PIN attempts

Abstract

An access trial control device for a card, such as a financial or business transaction card or the like, which is inserted in an access terminal for use and carries a confidential code which is compared with an access code type by the user on the terminal. For each access trial the result, acceptance or refusal, of the comparison is permanently recorded by non volatile memory means in the card. The number of consecutive access trials refused is counted in a counter and is detected by a control circuit which disables the card when such number reaches a predetermined value. Each accepted access trial resets the counter to zero.

Claims

1. A data bearing card or the like for gaining access to a utilization device, the card comprising means for storing an identification code which is interrogated for validity during an access attempt, said card further comprising permanent recording means of all valid and invalid access attempts and of the indication resulting from such respective attempts.

2. A card according to claim 1, wherein said recording means comprise respective first and second store positions for the recording of the attempts recognized as valid and for the recording of the attempts recognized as invalid.

3. A card according to claim 1, wherein said recording means are of the non-destructive type.

4. A circuit for validating correct access to a utilization device, said circuit incorporated in a portable object and comprising:

means incorporating an identification code of the object for undergoing interrogation during each access attempt; and

means for permanently recording all the consecutive access attempts which are recognized as valid or invalid.

5. A circuit for validating current access to a utilization device, said circuit incorporated in a portable object and comprising:

means for permanently recording consecutive valid and invalid access attempts;

means for initializing said circuit when any access attempt is made;

means for reading out attempt data from said permanent recording means during initializing;

means for counting consecutive invalid access attempts derived from the read-out of said recording means; and

means for detecting a pedetermined count of consecutive invalid attempts;

wherein said counting means is reset in response to a valid access attempt, when said valid attempt occurs before said predetermined invalid attempt count occurs.

6. A circuit for validating correct access to a utilization device, said circuit incorporated into an object, and wherein each access attempt is instituted by an interrogation of said object to ascertain access validity, the circuit comprising:

means adapted for permanently recording all invalid and valid access attempts;

counting means for detecting the occurrence of a preselected number of invalid attempts for preventing access to the utilization device;

means adapted for resetting said counting means in response to a signal indicating the occurrence of a valid access attempts prior to an occurrence of the preselected number of invalid attempts; and

means adapted for initializing said counting means by a read-out of said recording means at the moment of each connection of said circuit to a utilization device occurring before completion of the first access attempt following said connection.

7. A methood for restricting the use of a data bearing card or the like havng a permanent memory, the card enabling completion of a transaction with a controlled access data terminal, the method comprising the steps:

comparing a code stored in the card memory with a code entered on the terminal for validating an attempted transaction;

storing the result of the validation attempt in the card memory at a first memory address;

computing the total number of accepted and rejected transactions upon reintroduction of the card to a terminal, prior to validation of codes;

comparing the code stored in the cord memory with a code entered in the terminal for validating another attempted transaction, the result of the latter validation stored at a second memory address dependent upon the first but removed therefrom by a preselected integer;

changing the least significant bit of the first address by a binary zero if an unfavorable validation attempt occurs and by a binary one if a favorable validation attempt occurs;

storing the result of each succeeding validation attempt; and

prohibiting validation when a predetermined number of consecutive invalid attempts are made.

8. A data bearing card or the like for validating an attempted transaction with a controlled access data terminal, the card comprising:

a non-destructive memory for storing the occurrence of each attempted transaction and the result thereof;

the memory having a first register for storing the valid attempts and a second register for storing the invalid attempts, the first register having even addresses and separated from other addresses in this register by a preselected even number, varying between 0 and 2k; and

the second register having odd addresses and separated from other addresses in this register by the same number and varying between 1 and 2k+1.

9. The data bearing card set forth in claim 8, wherein the terminal comprises:

means for comparing a code encoded on the card with a code entered on the terminal and generating a signal indicating a valid code entry;

a counter connected to the code comparing means for incrementing a count indicative of an invalid entry;

means connected in circuit with the code comparing means for resetting the counter in response to a valid code entry; and

means for decoding a preselected count in the counter and preventing further use of the card.