Method and apparatus for verifying secure document timestamping

• US 6,959,387 B2
• Filed: 07/17/2001
• Issued: 10/25/2005
• Est. Priority Date: 03/21/1996
• Status: Expired

• Current Assignee: Inventor Holdings LLC (Walker Innovation Inc. (f/k/a Patent Properties, Inc.))
• Original Assignee: Walker Digital LLC (Walker Innovation Inc. (f/k/a Patent Properties, Inc.))
• Inventors: Walker, Jay S., Schneier, Bruce, Jorasch, James A., Alderucci, Dean P.
• Primary Examiner(s): Peeso, Thomas R.
• Application Number:
  US09/907,112
• Publication Number:
  US 20020120850A1
• Time in Patent Office: 1,561 Days
• Field of Search: 713/178, 713/200, 713/201
• US Class Current: 713/178
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 2209/805 Lightweight hardware, e.g. radio-frequency identification [RFID] or sensor
• CPC Class Codes: H04L 9/0866 involving user or device identifiers, e.g. serial number, physical or biometrical information, DNA, hand-signature or measurable physical characteristics
• CPC Class Codes: H04L 9/3271 using challenge-response
• CPC Class Codes: H04L 9/3297 involving time stamps, e.g. generation of time stamps
• CPC Class Codes: H04L 9/50 using hash chains, e.g. blockchains or hash trees

Abstract

According to one embodiment of the invention, a method is provided for receiving a timestamp from a caller via a telephone connection; receiving a device identifier from the caller, in which the device identifier identifies a device; determining a cryptographic key based on the device identifier; determining an indication of a time based on the timestamp and the cryptographic key; providing the indication of the time to the caller; determining an account; and charging a fee to the account.

Claims

1. A method comprising:

receiving a timestamp from a caller via a telephone connection;

receiving a device identifier from the caller, in which the device identifier identifies a device;

determining a cryptographic key based on the device identifier;

determining a representation of a time based on the timestamp and the cryptographic key;

providing the representation of the time to the caller;

determining an account; and

charging a fee to the account.

2. The method of claim 1, in which the timestamp is optically detectable on a physical document.

3. The method of claim 1, in which receiving the timestamp comprises:

receiving the timestamp at a central controller.

4. The method of claim 1, further comprising:

receiving a telephone call from the caller.

5. The method of claim 1, in which receiving the timestamp comprises:

receiving a sequence of DTMF signals; and

determining the timestamp based on the DTMF signals.

6. The method of claim 5, in which the sequence is entered by the caller at a keypad.

7. The method of claim 1, in which receiving the timestamp comprises:

receiving a sequence of signals via an interactive response unit (IRU).

8. The method of claim 1, in which receiving the timestamp comprises:

receiving the timestamp via a toll-based telephone line.

9. The method of claim 8, in which the toll-based telephone line is associated with a 900 number.

10. The method of claim 1, in which the timestamp comprises a sequence of alphanumeric characters.

11. The method of claim 1, in which determining the account comprises:

receiving an account identifier that identifies the account.

12. The method of claim 1, in which the timestamp comprises an account identifier that identifies the account.

13. The method of claim 1, in which the account is associated with the caller.

14. The method of claim 1, in which the account is associated with a third party.

15. The method of claim 1, in which determining the account comprises:

determining the account based on the device identifier.

16. The method of claim 1, in which the account is a prepaid account.

17. The method of claim 1, in which charging the fee comprises:

debiting the account based on the fee.

18. The method of claim 1, in which determining the representation of the time comprises:

performing a cryptographic operation on the timestamp.

19. The method of claim 1, in which determining the representation of the time comprises:

decrypting the timestamp based on the cryptographic key.

20. The method of claim 1, in which providing the representation of the time comprises:

transmitting the representation of the time to the caller.

21. The method of claim 1, in which providing the representation of the time comprises:

displaying the representation of the time to the caller.

22. The method of claim 1, in which determining the cryptographic key comprises:

selecting a database record based on the device identifier, in which the database record comprises the device identifier.

23. A method comprising:

receiving a sequence of DTMF signals from a caller via a telephone connection;

determining a timestamp based on the DTMF signals;

receiving a device identifier from the caller, in which the device identifier identifies a device;

determining a cryptographic key based on the device identifier;

determining a representation of a time based on the timestamp and the cryptographic key;

providing the representation of the time to the caller;

determining an account; and

charging a fee to the account.

24. A method comprising:

receiving a timestamp from a timestamp recipient via an Internet connection;

receiving a device identifier via the Internet connection, in which the device identifier identifies a device;

determining a cryptographic key based on the device identifier;

determining a representation of a time based on the timestamp and the cryptographic key;

providing the representation of the time to the timestamp recipient via the Internet connection;

determining an account; and

charging a fee to the account.