METHOD OF OPERATING A SECURITY TOKEN, COMPUTER PROGRAM PRODUCT AND SECURITY TOKEN

• US 20150121499A1
• Filed: 10/29/2014
• Published: 04/30/2015
• Est. Priority Date: 10/29/2013
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Suwald, Thomas, Burghardt, Arne
• Granted Patent: US 10,609,012 B2
• Time in Patent Office: Days
• US Class Current: 726/7
• CPC Class Codes: G06F 21/32 using biometric data, e.g. fingerprints, iris scans or voiceprints
• CPC Class Codes: G06F 21/35 communicating wirelessly
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/028 switching on or off only a part of the equipment circuit blocks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

There is provided a method of operating a security token, said security token comprising a secure element and a microcontroller unit being coupled to said secure element, wherein: the secure element receives an authentication command from a host device while the microcontroller unit is in a first sleep state; the secure element decodes the authentication command, sends a corresponding authentication request to the microcontroller unit and subsequently enters into a second sleep state; the microcontroller unit wakes up upon receiving the authentication request and subsequently determines an amount of available power; the microcontroller unit processes the authentication request only if the amount of available power exceeds a threshold. Furthermore, a corresponding computer program product and a corresponding security token are provided.

Claims

1. A method of operating a security token, said security token comprising a secure element and a microcontroller unit being coupled to said secure element, wherein:

the secure element receives an authentication command from a host device while the microcontroller unit is in a first sleep state;

the secure element decodes the authentication command, sends a corresponding authentication request to the microcontroller unit and subsequently enters into a second sleep state;

the microcontroller unit wakes up upon receiving the authentication request and subsequently determines an amount of available power; and

the microcontroller unit processes the authentication request only if the amount of available power exceeds a threshold.

2. A method as claimed in claim 1, wherein the microcontroller unit processes the authentication request by controlling a user interface for capturing user credentials.

3. A method as claimed in claim 2, wherein, when the microcontroller unit has captured the user credentials through said user interface, the microcontroller unit sends said user credentials to the secure element and subsequently returns to the first sleep state.

4. A method as claimed in claim 3, wherein the secure element wakes up upon receiving the user credentials and verifies said user credentials in order to generate an authentication result.

5. A method as claimed in claim 4, wherein the secure element, after having generated the authentication result, sends the authentication result to the host device and subsequently returns to the second sleep state.

6. A method as claimed in claim 1, wherein the microcontroller unit determines the amount of available power by measuring the voltage present on an antenna of said security token.

7. A method as claimed in claim 1, wherein the microcontroller unit, when the amount of available power does not exceed the threshold, further monitors said amount of available power and processes the authentication request if the amount of available power changes such that it exceeds the threshold.

8. A method as claimed in claim 1, wherein the secure element is in a third sleep state prior to receiving the authentication command, and wherein the secure element wakes up upon receiving said authentication command.

9. A method as claimed in claim 1, wherein the microcontroller unit is in a reset state prior to being in the first sleep state.

10. A method as claimed in claim 1, wherein the threshold is predetermined.

11. A computer program product comprising program elements which, when being executed by a secure element or a microcontroller unit, carry out or control steps of a method as claimed in claim 1.

12. A security token comprising a secure element and a microcontroller unit being coupled to said secure element, wherein:

the secure element is arranged to receive an authentication command from a host device while the microcontroller unit is in a first sleep state;

the secure element is arranged to decode the authentication command, to send a corresponding authentication request to the microcontroller unit and to subsequently enter into a second sleep state;

the microcontroller unit is arranged to wake up upon receiving the authentication request and to subsequently determine an amount of available power; and

the microcontroller unit is arranged to process the authentication request only if the amount of available power exceeds a threshold.

13. A security token as claimed in claim 12, said security token being a smart card.