US 4,214,230 A · Personal identification system

Abstract

A method and apparatus for verifying that the bearer of a card (e.g., credit card, bank card, etc.) is authorized to use the card. The card bears machine-readable indicia of an account number (PAN) and the bearer of the card has memorized a personal identification number (PIN). There is associated with the PAN a check number (PCN) which is derived by (1) generating a first cipher Y1 by encrypting the PAN using the PIN in combination with a secret security number as a key, the bits of which address a data encryption process; (2) generating a second cipher by decrypting the first cipher using the secret security number as a key so that the decryption process is the reverse of the encryption process; and (3) storing the second cipher as the check number PCN in a machine-accessible location, which may be in a separate memory or recorded on the card itself. Verification is accomplished by (a) sensing the PAN from the machine-readable indicia on the card; (b) enciphering the PAN with respect to the data encryption process under control of a key which is a combination (such as by addition) of the PIN and the secret security number to thereby produce a third cipher; (c) sensing the PCN from the machine-accessible location; (d) enciphering the PCN with respect to the data encryption process under control of a key which is the secret security number to thereby produce a fourth cipher; and (e) accepting the card as valid provided the third and fourth ciphers bear a predetermined relationship to each other, such as equality.

Claims11

Dependent claims

For use in a system for providing transaction security to a cardholder's account in a commercial institution, wherein the cardholder has a secret identification number, and the institution has a secret number, the combination comprising:

means having a data input, a data output and a key input, for enciphering clear data applied at said data input under control of a key comprised of key bits applied at said key input, in accordance with an enciphering process;
means for applying a customer account number to the data input of said enciphering means;
and,
means for applying at the key input the combination of said customer's secret number and said institution's secret number,
whereby a first cipher is generated at the output of said enciphering means.

2 more elements

For use with a card bearing machine-readable indicia of an account number (PAN) and wherein an authorized user of said card has memorized a personal identification number (PIN), and wherein there is associated with said PAN a check number (PCN) which is derived by (1) generating a first cipher Y1 by encrypting said PAN using said PIN in combination with a first secret security number as a key, the bits of which address a data encryption process;

and (2) generating a check number (PCN) by decrypting said first cipher using a second secret security number as a key so that the decryption process is the reverse of said data encryption process;
and (3) storing said check number (PCN) in a machine-accessible location, the method of verifying that the bearer of said card is authorized to use said card comprising the steps of:
(a) Sensing said PAN from said machine-readable indicia on said card;
(b) Enciphering said PAN with respect to said data encryption process under control of the key which is a combination of said PIN and said first secret security number to thereby produce a third cipher;
(c) Sensing said PCN from said machine-accessible location;
(d) Enciphering said PCN with respect to said data encryption process under control of said key which is said second secret security number to thereby produce a fourth cipher;
(e) Comparing said third and fourth ciphers;
and,
(f) Accepting said card as valid providing said third and fourth ciphers compare favorably with each other.

6 more elements

Dependencies are inferred from the claim text.

Personal identification system

Life of this patent

Personal identification system

Life of this patent

Abstract

Claims11