METHODS AND SYSTEMS FOR RECOGNIZING TAMPER EVENTS

• US 20080192240A1
• Filed: 02/08/2007
• Published: 08/14/2008
• Est. Priority Date: 02/08/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Dalzell, William J., Tucker, James L., Fleischman, Scott G., Warrensford, Kara L.
• Granted Patent: US 8,284,387 B2
• Time in Patent Office: Days
• US Class Current: 356/73.1
• CPC Class Codes: G01M 11/3109 Reflectometers detecting the back-scattered light in the time-domain, e.g. OTDR
• CPC Class Codes: G06F 21/87 by means of encapsulation, e.g. for integrated circuits
• CPC Class Codes: G06F 2221/2101 Auditing as a secondary aspect
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen
• CPC Class Codes: G08B 13/186 using light guides, e.g. optical fibres

Abstract

A method of recognizing a tamper event is provided. The method uses an optical medium having a unique signature, and transmits at least one light wave into the optical medium. The light wave is altered by the unique signature of the optical medium and at least one property of the light wave is measured. Access to at least a portion of a system is conditioned based on the at least one property of the light wave.

Claims

1. A method of recognizing a tamper event comprising:

transmitting at least one light wave into an optical medium, the optical medium having a unique signature;

measuring at least one property of the light wave, wherein the light wave was altered by the unique signature of the optical medium; and

conditioning access to at least a portion of a system based on the at least one property of the light wave.

2. The method of claim 1, wherein conditioning access further comprises:

allowing access only if the at least one property of the light wave is unchanged.

3. The method of claim 1, further comprising:

receiving the light wave at one end of the optical medium, wherein measuring the at least one property of the optical medium measures a property of the light wave received.

4. The method of claim 1, further comprising:

transmitting a second light wave into an second optical medium, the second optical medium having a unique signature;

measuring at least one property of the second light wave, wherein the second light signal was altered by the unique signature of the second optical medium; and

wherein conditioning access calculates a differential between the at least one property of the first light wave and the at least one property of the second light wave.

5. The method of claim 1, further comprising:

receiving the light wave at an end of the optical medium which is opposite of an end in which the light wave was transmitted.

6. The method of claim 1, further comprising:

receiving at least one reflection of the transmitted light wave at a same end of the optical medium in which the light wave was transmitted.

7. The method of claim 1, wherein conditioning access further comprises:

generating an encryption key from the measured characteristic of the optical medium.

8. The method of claim 7, wherein conditioning access further comprises:

decrypting stored data with the encryption key.

9. An apparatus for recognizing a tamper event, comprising:

an optical medium configured to have a unique signature, wherein the unique signature is configured to alter a property of a light wave traveling through the optical medium;

a light emitter in optical communication with the optical medium;

an opto-electrical component coupled to the optical medium and operable to measure at least one property of a light wave that has traveled in the optical medium; and

wherein the apparatus is configured to determine whether the at least one property of a light wave that has traveled in the optical medium has been altered.

10. The apparatus of claim 9, further comprising:

an access system operable to condition access to at least a portion of the apparatus based on the at least one property of a light wave that has traveled in the optical medium.

11. The apparatus of claim 10, wherein the access system is unique and is configured to generate a generic key from the unique properties of a light wave that traveled in the optical medium.

12. The apparatus of claim 9, wherein the optical medium comprises one or more optical fibers.

13. The apparatus of claim 10, wherein the optical medium is fixed permanently in place.

14. The apparatus of claim 9, further comprising:

protected electronics;

a capsule covering the protected electronics; and

wherein the optical medium is disposed about the capsule.

15. The apparatus of claim 14, wherein the capsule also covers the opto-electrical component and the access system.

16. A method of recognizing a tamper event comprising:

forming an optical fiber to have a unique signature;

measuring at least one value relating to the optical properties of the optical fiber; and

conditioning access to a system based on the at least one value.

17. The method of claim 16, further comprising:

generating a key from the at least one value.

18. The method of claim 16, wherein forming an optical fiber to have a unique signature further comprises:

bending the optical fiber.

19. The method of claim 16, wherein forming an optical fiber to have a unique signature further comprises:

cutting the optical fiber.

20. The method of claim 16, wherein forming an optical fiber to have a unique signature further comprises:

imbedding at least one material in the optical fiber.