Secure storage of monetary equivalent data systems and processes

• US 5,604,343 A
• Filed: 05/24/1994
• Issued: 02/18/1997
• Est. Priority Date: 05/24/1994
• Status: Expired due to Term

• Current Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Original Assignee: Dallas Semiconductor Corporation (Analog Devices, Inc.)
• Inventors: Curry, Stephen M., Bolan, Michael L.
• Primary Examiner(s): Hajec, Donald T.
• Assistant Examiner(s): LE, THIEN MINH
• Application Number:
  US08/247,941
• Time in Patent Office: 1,001 Days
• Field of Search: 235/380, 235/492, 235/385, 235/491, 235/441
• US Class Current: 235/492
• 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: G06Q 20/357 Cards having a plurality of specified features
• CPC Class Codes: G06Q 20/4097 using mutual authentication between devices and transaction partners
• CPC Class Codes: G07F 1/06 Coins specially adapted to operate coin-freed mechanisms
• CPC Class Codes: G07F 7/0866 by active credit-cards adapted therefor G07F7/1008 takes precedence
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system

Abstract

A secure monetary system comprises an electronic module and equipment to access the electronic module. The electronic module comprising a substantially token-shaped module and secure memory circuitry to store monetary information. The secure memory positioned in the substantially token-shaped module. The equipment accesses and manipulates the monetary information stored in the memory in the electronic module. The equipment comprises memory to store control and encryption programs and the memory is coupled to a microprocessor, which is also coupled to the electronic module and a control panel. The microprocessor is secure.

Claims

1. An electronic monetary system, comprising:

(a) an electronic module, said electronic module storing electronic data, said electronic data including monetary information and a unique unalterable registration number, said electronic module further including a first and a second surface, said first surface being electrically isolated from said second surface;

(b) means for manipulating and securing said electronic data;

(c) means for interfacing said electronic module with said manipulating and securing means, said interfacing means including a probe electrically connected to said manipulating means, said probe including a first and a second conductive contact for directly interfacing with, respectively, said first and second surfaces; and

(d) electronic circuitry disposed within said electronic module, said electronic circuitry being electrically connected to said first and said second surfaces, said electronic circuitry including one-way alterable random access memory for storing bits of said monetary information, wherein said bits can only be changed from one state to another state, and further wherein each of said first and second surfaces consists of a single electrical contact.

2. A system as recited in claim 1, wherein:

(a) said first conductive contact of said probe is a single wire axially disposed within said second conductive contact of said probe.

3. A system as recited in claim 2, wherein:

(a) said means for manipulating and securing includes error detection circuitry for identifying and verifying said registration number.

4. A system as recited in claim 3, wherein:

(a) said bits of monetary information stored in said one-way alterable random access memory include a sequence of credit bits and a sequence of debits bits; and

(b) said means for manipulating and securing includes circuitry for writing credit bits and debits into said one-way alterable random access memory.

5. A method for securing and nanipulating monetary data in an electronic monetary system, comprising the steps of:

(a) reading a unique registration number associated with an electronic module;

(b) checking the validity of the registration number;

(c) reading the status of memory registers of the electronic module to find a first page of memory available;

(d) reading the information stored in the first available page of memory;

(e) confirming the validity of the read using CRC calculation circuitry;

(f) applying an encryption algorithm to the unique registration number to generate a unique secret number;

(g) recording bits of memory read from the first available page pursuant to the secret number using a predetermined scrambling technique;

(h) representing credits as zero bits starting from the least significant bit of the reordered bits of memory; and

(i) representing debits as zero bits staring from the most significant bit of the reordered bits of memory.

6. The method as recited in claim 5, further comprising the steps of:

(a) determining if the number of credits is greater than the number of debits, and if true, adding a zero bit to the unscrambled sequence; and

(b) writing the zero bit in its scrambled position.

7. The method as recited in claim 5, further comprising the steps of:

(a) conducting a write operation to write a bit from a one to a zero for debit operation.

8. An electronic monetary system, comprising:

(a) means for storing electronic data, said electronic data including monetary information and a unique unalterable registration number;

(b) means for manipulating and securing said electronic data; and

(c) means for interfacing said electronic data storing means with said manipulating and securing means, said means for interfacing including a probe electrically connected to said manipulating and securing means, said probe including a first and a second conductive contact.

9. The electronic monetary system as recited in claim 8, wherein said first conductive contact of said probe is a single wire axially disposed within said second conductive contact of said probe.

10. The electronic monetary system as recited in claim 8, wherein said means for manipulating and securing includes error detection circuitry for identifying and verifying said unique and unalterable registration number.

11. The electronic monetary system as recited in claim 8, wherein said means for storing electronic data comprises:

(a) an electronic data carrier;

(b) electronic circuitry disposed within said electronic data carrier, said electronic circuitry including one-way alterable random access memory for storing bits of said monetary information, wherein said bits can only be changed from one state to another state.

12. The electronic monetary system as recited in claim 11, wherein:

(a) said electronic data carrier includes a first and second surface, said first surface being electrically isolated from said second surface; and

(b) said electronic circuitry is electrically connected to said first and second surfaces.

13. The electronic monetary system as recited in claim 12, wherein:

(a) each of said first and second surfaces consists of a single electrical contact.