Apparatus and method for securing beacons

• US 8,953,794 B1
• Filed: 08/01/2013
• Issued: 02/10/2015
• Est. Priority Date: 08/01/2013
• Status: Expired due to Fees

• Current Assignee: Qualcomm technologies international, ltd. (Qualcomm, Inc.)
• Original Assignee: Cambridge Silicon Radio Limited (Qualcomm, Inc.)
• Inventors: Graube, Nicolas
• Primary Examiner(s): Colin, Carl
• Assistant Examiner(s): Shayanfar, Ali
• Application Number:
  US13/956,687
• Time in Patent Office: 558 Days
• Field of Search: 380/277, 380/44, 380/262, 380/280
• US Class Current: 380/44
• 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 Salt value;

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

calculate a checksum value of the salted identification value;

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 salted identification value and the checksum 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 configured to generate 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 integer multiple of S.

4. The short-range communications tag according to claim 1 further comprising a transceiver, wherein the processor is further configured to:

cause the transceiver to establish a communications channel with a field service application;

receive, via the communications channel, a seed value for use in generating the sequence of encryption keys, a reference value for the clock value and the schedule for generating new encryption keys of the sequence of encryption keys; and

configure the encryption generation of the processor and the clock circuit with the respective seed and reference values.

5. The short-range communications tag according to claim 4, wherein the processor is configured to cause the transceiver to establish a secure communications channel as the communications channel with the field service application.

6. The short-range communications tag according to claim 1 wherein the unique identification value further includes data values indicating operational parameters of the short-range communications tag.

7. 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 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 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 to obtain a further decrypted value including the tag ID value, extract the checksum value from the further decrypted value and generate the further checksum value of at least the tag ID value until the checksum matches the further checksum value;

when 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.

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

cause the communications transceiver to establish a communications channel with the server; and

receive, via the communications channel, the plurality of encryption keys and the predetermined configuration data.

9. The mobile listening device according to claim 8, wherein the processor is configured to cause the communications transceiver to establish a secure communications channel as the communications channel with the server.

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

retrieving a unique identification value from a memory;

generating a Salt value;

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

calculating a checksum value of the salted identification value;

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 salted identification value and the checksum value according to a predetermined encryption algorithm to generate an encrypted unique identification value as the tag identification value; and

broadcasting the tag identification value by a transmitter coupled to the processor.

11. The method for encrypting the tag ID according to claim 10, 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.

12. 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.

13. The method for encrypting the tag ID according to claim 12, wherein the establishing of the communications channel with the field service application includes establishing a secure communications channel with the field service application.