Radio frequency identification secret handshakes

• US 8,643,475 B1
• Filed: 04/13/2010
• Issued: 02/04/2014
• Est. Priority Date: 04/13/2009
• Status: Expired due to Fees

• Current Assignee: Intel Corporation, University of Washington
• Original Assignee: University of Washington
• Inventors: Kohno, Tadayoshi, Czeskis, Alexei, Koscher, Karl, Smith, Joshua R
• Primary Examiner(s): Lim, Steven
• Assistant Examiner(s): Yacob, Sisay
• Application Number:
  US12/759,133
• Time in Patent Office: 1,393 Days
• Field of Search: 340/1.1, 340/10.1, 340 105- 1052, 340/13.25, 340/13.26, 726/1, 726/4, 726/5, 726/9, 726/17, 726 20- 22, 726 26- 33, 235/380, 235/492, 345/156, 345/158, 713/182, 463/29, 715/863
• US Class Current: 340/10.51
• CPC Class Codes: G06K 19/07345 by activating or deactivating at least a part of the circuit on the record carrier, e.g. ON/OFF switches
• CPC Class Codes: H04Q 2213/13095 PIN / Access code, authentication

Abstract

An approach for defending radio frequency identification (RFID) tags and other contactless cards against ghost-and-leech (a.k.a. proxying, relay, or man-in-the-middle) attacks incorporates gesture recognition techniques directly implemented with the RFID tags or contactless cards. These tags or cards will only engage in wireless communications when they internally detect “secret handshakes.” A secret handshake recognition system is implemented on a passive WISP RFID tag having a built-in accelerometer. This approach is backward compatible with existing deployments of RFID tag and contactless card readers and is also designed to minimize the changes to the existing usage model of certain classes of RFID and contactless cards, such as access cards that are kept in a wallet or purse, by enabling execution of secret handshakes without removing the card. This novel approach can also improve the security and privacy properties in other uses of RFID tags, e.g., contactless payment cards.

Claims

1. A method for enabling communication between a tag and a reader configured to read the tag, the method comprising:

determining, by at least one component associated with the tag, a pattern of movement of the tag;

comparing, by a microcontroller carried by the tag, the pattern of movement with a predefined pattern of movement, wherein comparing the pattern of movement with a predefined pattern of movement includes calculating a cross-correlation value of the pattern of movement with the predefined pattern of movement; and

activating the tag based on the comparison between the pattern of movement and the predefined pattern of movement;

wherein an instruction set used by the microcontroller for calculating the cross-correlation value of the pattern of movement with the predefined pattern of movement does not include a multiplication instruction.

2. The method of claim 1, wherein the predefined pattern of movement includes at least one of:

alpha, key twist, hip twist, circle, double circle, triangle, 1-left-1-right, 1-right-1-left, and 1.5-wave.

3. The method of claim 1, further comprising receiving an input from a user for initializing the tag for activation.

4. The method of claim 3, wherein the input includes the user moving the tag according to a pattern to establish the predefined pattern.

5. The method of claim 3, wherein the input includes the user selecting the predefined pattern from a plurality of predefined patterns.

6. An access card that is configured to carry a tag configured to perform the method of claim 1.

7. The access card of claim 6, further comprising a motion sensor configured to detect motion corresponding to the pattern of movement.

8. The access card of claim 7, wherein the motion sensor comprises an accelerometer.

9. The access card of claim 7, wherein the tag includes a radio frequency identification (RFID) tag that is configured to be activated based on the detected motion of the motion sensor.

10. The access card of claim 9, further comprising a component that is configured to perform at least one of the following actions:

storing the predefined pattern, comparing the pattern of movement with the predefined pattern of movement, and/or activating the RFID tag based on the detected motion of the motion sensor.

11. The method of claim 1, wherein activating the tag based on the comparison between the pattern of movement and the predefined pattern of movement includes activating the tag upon determining that the cross-correlation value is greater than a threshold value.

12. The method of claim 1, wherein calculating the cross-correlation value includes performing a normalized cross-correlation to reduce the impact of high magnitude samples.

13. The method of claim 1, wherein calculating the cross-correlation value includes zeroing out samples of the pattern of movement that exceed one or more magnitude thresholds.

14. The method of claim 1, wherein calculating the cross-correlation value includes adding together samples from the pattern of movement to be multiplied by a common value from the predefined pattern of movement before performing the multiplication.

15. The method of claim 14, wherein calculating the cross-correlation value further includes decomposing the multiplication into a summation of multiplications of powers of 2.