APPARATUS AND METHOD FOR SECURING BEACONS

• US 20150036823A1
• Filed: 10/13/2014
• Published: 02/05/2015
• Est. Priority Date: 08/01/2013
• Status: Active Grant

• Current Assignee: Qualcomm technologies international, ltd. (Qualcomm, Inc.)
• Original Assignee: Cambridge Silicon Radio Limited (Qualcomm, Inc.)
• Inventors: Graube, Nicolas
• Granted Patent: US 9,241,262 B2
• Time in Patent Office: Days
• US Class Current: 380/274
• CPC Class Codes: H04L 63/0414 during transmission, i.e. party's identity is protected against eavesdropping, e.g. by using temporary identifiers, but is known to the other party or parties involved in the communication
• CPC Class Codes: H04L 63/068 using time-dependent keys, e.g. periodically changing keys cryptographic mechanisms or cryptographic arrangements for controlling usage of secret information H04L9/088
• 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 9/0869 involving random numbers or seeds
• CPC Class Codes: H04W 12/02 Protecting privacy or anonymity, e.g. protecting personally identifiable information [PII]
• CPC Class Codes: H04W 12/04 Key management, e.g. using generic bootstrapping architecture [GBA]
• CPC Class Codes: H04W 12/75 Temporary identity
• CPC Class Codes: H04W 4/021 Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

A short-range communication tag includes a transmitter, a clock circuit providing a clock value and a memory containing a unique identification value. The tag further includes a processor which generates encryption keys with a period of K seconds and combines the unique identification value with the encryption key, according to a predetermined encryption method, to generate an obfuscated unique identification value. The tag further includes a short-range transmitter to transmit the tag identification value.

Claims

1. A short-range communication tag comprising:

a transmitter;

a clock circuit providing a clock value that changes with a period of a clock signal;

a memory configured to contain a unique identification value;

a processor, coupled to the memory, the clock circuit and the transmitter, the processor being configured to;

generate a sequence of encryption keys, wherein the processor is configured to generate new encryption keys in the sequence of encryption keys with a period of K seconds, according to a schedule, where K is an integer; and

for a current encryption key in the sequence of encryption keys;

combine the unique identification value with the current encryption key, according to a predetermined encryption method, to generate an encrypted unique identification value as a tag identification value;

and cause the transmitter to transmit the tag identification value.

2. The short-range communications tag according to claim 1, wherein the processor is configured to generate a sequence of pseudo-random number (PN) values as the sequence of encryption keys.

3. The short-range communications tag according to claim 1, wherein the processor is further configured to:

generate a Salt value;

insert bits of the Salt value into the unique identification value to generate a salted identification value;

wherein the processor is configured to combine the salted identification value with the current encryption key to generate the encrypted unique identification value.

4. The short-range communications tag according to claim 3, wherein the processor is further configured to:

calculate a checksum value of the salted identification value; and

concatenate the checksum value with the tag identification value before causing the transmitter to transmit the tag identification value.

5. The short-range communications tag according to claim 3, wherein the processor is further configured to:

calculate a checksum value of the salted identification value;

concatenate the checksum value with the salted identification value to form a further salted identification value; and

combine the current encryption key with the further salted identification value to generate the tag identification value.

6. A mobile listening device comprising:

a short-range receiver;

a memory which holds a plurality of encryption keys;

a communications transceiver; and

a processor coupled to the short-range receiver, the memory and the communications transceiver, the processor being configured to;

receive an encrypted tag value via the short-range receiver;

process at least a portion of the encrypted tag value using a predetermined decryption method and one of the plurality of encryption keys to generate a decrypted value including a tag ID value;

extract a checksum value from one of the encrypted tag value or the decrypted value;

generate a further checksum value of at least the tag ID value;

compare the checksum value and the further checksum value and,

if the checksum value matches the further checksum value, remove a Salt from the tag ID value, as identified by predetermined configuration data, to generate a unique tag ID value

7. The mobile listening device according to claim 6, wherein the processor is further configured to:

if the checksum value does not match the further checksum value process at least the portion of the encrypted tag value using the predetermined decryption method and another one of the plurality of encryption keys until the checksum matches the further checksum.

8. A method for encrypting a tag identifier (ID) of a short-range communications tag comprising:

retrieving a unique identification value from a memory;

generating, by a processor of the short-range communications tag, a sequence of encryption keys with a period K seconds, as determined by a clock value;

combining, by the processor, a currently generated one of the encryption keys with the unique identification value according to a predetermined encryption algorithm to generate an encrypted unique identification value as the tag ID; and

broadcasting the tag ID by a transmitter coupled to the processor.

9. The method for encrypting the tag ID according to claim 8, further comprising:

generating a Salt value;

inserting bits of the Salt value into the unique identification value to generate a salted identification value; and

wherein the combining of the currently generated encryption key with the unique identification value includes combining the salted identification value with the current encryption key to generate the encrypted unique identification value.

10. The method for encrypting the tag ID according to claim 9, further comprising:

calculating a checksum value of the salted identification value; and

concatenating the checksum value with the tag identification value before broadcasting the tag identification value;

11. The method for encrypting the tag ID according to claim 9, further comprising:

calculating a checksum value of the salted identification value;

concatenating the checksum value with the salted identification value to form a further salted identification value; and

wherein the combining includes combining the encryption key with the further salted identification value to generate the tag identification value.

12. The method for encrypting the tag ID according to claim 11, further comprising:

generating, by the processor, a pseudo-random number (PN) value as the Salt value with a period of S seconds, where S is an integer and K is a multiple of S.

13. The method for encrypting the tag ID according to claim 11, further comprising:

establishing a communications channel with a field service application; and

receiving, via the communications channel, a seed value for use in generating the encryption keys, a reference value for the clock value and the values of K and S.

14. Apparatus comprising:

a clock generator having a clock value that changes in response to a clock signal;

a transceiver;

a memory;

a processor coupled to the transceiver, the clock signal generator and the memory, the processor being configured to;

generate a sequence of encryption keys and seed values including, a current encryption key and a current seed value and store at least a portion of the sequence of encryption keys and seed values in the memory;

retrieve from the memory the current seed value and the current clock value;

establish a transmission connection with a field service application via the transceiver; and

transmit the current seed value and current clock value to the field service application via the transmission connection.

15. The apparatus according to claim 14, wherein the processor is configured to generate a sequence of pseudo-random number (PN) values as the sequence of encryption keys.

16. The apparatus of claim 14, wherein the processor is configured to establish a secure transmission connection as the transmission connection with the field service application.

17. The apparatus of claim 14, wherein the memory is configured to hold a new key generation schedule value and a new Salt generation schedule value;

and

the processor is configured to transmit the new key generation schedule value and the new Salt generation schedule value to the field service application with the retrieved seed value and the current clock value via the transmission connection.

18. The apparatus of claim 14, wherein the processor is further configured to:

transmit multiple ones of the encryption keys, including the current key to a listening device via the transceiver; and

receive, from the listening device, a tag ID.

19. The apparatus of claim 18, wherein the memory is configured to hold at least a previous encryption key and a next encryption key in addition to the current encryption key as the multiple encryption keys and the processor is configured to transmit the previous encryption key, the current encryption key and the next encryption key to the listening device via the transceiver.

20. The apparatus of claim 18, wherein the processor is configured to:

receive, via the transceiver, a request from the listening device for a further encryption key;

generate the further encryption key as a key in the sequence following the next encryption key; and

transmit the further encryption key to the listening device via the transceiver.