Time-bracketing infrastructure implementation

• US 5,966,446 A
• Filed: 06/30/1997
• Issued: 10/12/1999
• Est. Priority Date: 09/29/1995
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Davis, Derek L.
• Primary Examiner(s): Swann, Tod R.
• Assistant Examiner(s): CODDINGTON, TREVOR Q
• Application Number:
  US08/886,092
• Time in Patent Office: 834 Days
• Field of Search: 380/23, 380/25, 380/3, 380/4
• US Class Current: 713/178
• CPC Class Codes: H04L 2209/805 Lightweight hardware, e.g. radio-frequency identification [RFID] or sensor
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3297 involving time stamps, e.g. generation of time stamps

Abstract

Implemented preferably within a digital camera, an electronic device is used to prevent a captured data clip from being fraudulently altered without detection. The electronic device performs "time-bracketing" and may contain cellular phone circuitry to establish wireless communication to receive a state value used to preserve data integrity when time-stamping is performed in combination.

Claims

1. An electronic device comprising:

a data capture circuit to capture a data clip; and

a cryptographic circuit coupled to the data capture circuit, the cryptographic circuit to preserve integrity of the data clip by establishing that the data clip was captured after publication of information including a state value, the cryptographic circuit including;

a processor to perform operations on the data clip to produce a hash result, combines the state value with the hash result to produce a running hash value, and digitally signs the running hash value, and

communication circuitry to establish a communication link to transmit at least the running hash value to undergo a time-stamping operation.

2. The electronic device of claim 1, wherein the communication circuitry supports wireless communications.

3. The electronic device of claim 1, wherein the data capture circuit includes a sensor.

4. The electronic device of claim 1, wherein the cryptographic circuit further includes at least one storage element.

5. The electronic device of claim 4, wherein the at least one storage element contains a unique key pair, the running hash value and the state value loaded prior to the data capture circuit capturing the data clip.

6. The electronic device of claim 5, wherein the cryptographic circuit further includes cryptographic software contained in the at least one storage element.

7. The electronic device of claim 4, wherein the at least one storage element includes

a first storage element to contain a unique key pair;

a second storage element to contain the running hash value; and

a third storage element to contain the state value.

8. The electronic device of claim 1, wherein the communication circuitry of the cryptographic circuit further enables the state value to be updated.

9. A data capture system comprising:

a first source to capture a data clip and preserve integrity of the data clip, the first source including

a data capture circuit, and

a cryptographic circuit coupled to the data capture circuit, the cryptographic circuit to preserve integrity of the data clip by establishing that the data clip was captured after publication of information including a state value, to perform operations on the data clip and the state value to produce a running hash value, and to digitally sign the running hash value; and

a second source in communication with the first source.

10. The data capture system of claim 9, wherein the second source performing at least an authentication operation on information transmitted from the first source.

11. The data capture system of claim 9, wherein the data capture circuit of the first source includes a sensor.

12. The data capture system of claim 9, wherein the second source performs a time-stamping operation on information including the running hash value.

13. The data capture system of claim 9, wherein the cryptographic circuit of the first source includes communication circuitry to establish a wireless communication with at least the second source.

14. The data capture system of claim 13, wherein the cryptographic circuit of the first source further includes a processor coupled to the communication circuitry.

15. The data capture system of claim 14, wherein the cryptographic circuit of the first source further includes at least one storage element.

16. The data capture system of claim 15, wherein the at least one storage element of the cryptographic circuit contains a unique key pair, the running hash value and the state value loaded prior to the data capture circuit capturing the data clip.

17. The data capture system of claim 15, wherein the at least one storage element of the cryptographic circuit further includes cryptographic software.

18. The data capture system of claim 15, wherein the at least one storage element of the cryptographic circuit includes

a first storage element to contain a unique key pair;

a second storage element to contain the running hash value; and

a third storage element to contain the state value.

19. A method for preserving integrity of a data clip transmitted from a first source to a second source, the method comprising:

capturing a first data clip;

performing a hashing operation on at least the first data clip to produce a running hash value;

digitally signing the running hash value to produce a digital signature of the running hash value;

transferring at least the digital signature to the second source through wireless communications; and

performing one of a time-stamping operation and an authentication operation on at least the running hash value by the second source.

20. The method of claim 19, wherein the performing the hash operation includes

concatenating a state value to the first data clip;

and

hashing the state value and first data clip to produce the running hash value.

21. The method of claim 19, wherein the performing the hash operation includes:

performing a hashing operation on the first data frame to produce a first hash result;

incorporating the hash result with the running hash value;

concatenating a state value to the running hash value to produce a result; and

performing a hashing operation on the result to produce the running hash value.