Method and apparatus for verifying secure document timestamping

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.

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.    
     
     
       25. A method, comprising:
   generating, by a cryptoprocessor, a timestamping request for a series of timestamps;        generating, by the cryptoprocessor, the series of timestamps according to a schedule stored in a memory;        transmitting the series of timestamps to a recipient; and        charging a fee.     
     
     
       26. The method of  claim 25 , wherein the schedule includes at least one of regular and irregular intervals. 
     
     
       27. The method of  claim 25 , wherein the schedule is generated dynamically according to an algorithm. 
     
     
       28. The method of  claim 27 , wherein the algorithm provides for generating a future timestamp of the series of timestamps in response to at least one previous timestamp. 
     
     
       29. A computer readable medium storing instructions configured to direct a processor to:
   internally generate a timestamping request for a series of timestamps;        generate the series of timestamps according to a stored schedule;        transmit the series of timestamps to a recipient; and        charge a fee.     
     
     
       30. The computer readable medium of  claim 29 , wherein the instructions to generate the series of timestamps direct the processor to utilize a schedule that includes at least one of regular and irregular intervals. 
     
     
       31. The computer readable medium of  claim 29 , which further comprises instructions configured to direct the processor to utilize a schedule that is generated dynamically. 
     
     
       32. The computer readable medium of  claim 31 , in which the instructions for directing the processor to generate the series of timestamps further comprise instructions to direct the processor to utilize an algorithm in which a future series of timestamps is set in response to at least one previous timestamp. 
     
     
       33. An apparatus, comprising:
   a cryptoprocessor configured to internally generate a timestamping request for a series of timestamps;        a memory in communication with the cryptoprocessor and storing a program for directing the cryptoprocessor to generate the series of timestamps according to a stored schedule, and to determine a fee; and        an output device, controlled by the cryptoprocessor, for transmitting the series of timestamps to a recipient, and for outputting a charge for the fee.