Determining electric field distributions

Patent metadata

Field	Value
Publication number	US-11860207-B2
Application number	US-202017758143-A
Country	US
Kind code	B2
Filing date	Jan 31, 2020
Priority date	Jan 31, 2020
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

In an example, a method includes receiving an indication of an electrical parameter associated with at least part of a computing device. The method further includes determining whether or not the indication is indicative of an expected electric field distribution associated with a specified hardware configuration for the computing device.

First claim

The invention claimed is:

1. A method comprising:
receiving an indication of an electrical parameter associated with computing device; and
determining, using processing circuitry and a conductive element for modifying an electric field distribution to create a signature electric field distribution linked to the processing circuitry, whether or not the indication is indicative of the signature electric field distribution associated with computing device.

2. The method of claim 1 , where receiving the indication comprises receiving an indication of an electrical parameter measured at a plurality of locations associated with the computing device.

3. The method of claim 2 , where determining whether or not the indication is indicative of the signature electric field distribution associated with the the computing device comprises using a model to determine whether or not the indication of the electrical parameter measured at the plurality of locations is indicative of the signature electric field distribution, where the model is based on at least one of:
a previously-obtained indication of the electrical parameter measured at the plurality of locations; and
information regarding how a hardware component of the computing device influences the signature electric field distribution.

4. The method of claim 1 , where determining whether or not the indication is indicative of the signature electric field distribution associated with the computing device comprises:
comparing the indication of the electrical parameter with a previously-obtained indication of the electrical parameter; and
determining whether or not any deviation between the indication and the previously-obtained indication is indicative of an unexpected modification of the computing device.

5. The method of claim 1 , where determining whether or not the indication is indicative of the signature electric field distribution associated with a specified hardware configuration for the computing device comprises determining whether or not the indication meets a specified criterion with respect to the signature electric field distribution such that: where the specified criterion is met, a provenance of the computing device meets an expectation and where the specified criterion is not met, the provenance of the computing device does not meet the expectation.

6. The method of claim 1 , comprising causing a sensor to perform a measurement of the electrical parameter.

7. The method of claim 6 , comprising causing the sensor to perform the measurement with a specified sensitivity based on at least one of: a purpose of the sensor; a state of the computing device and a location of the sensor relative to the computing device.

8. The method of claim 1 , comprising causing a notification to be issued in response to a determination being made that the indication is inconsistent with the signature electric field distribution.

9. The method of claim 8 , where causing the notification to be issued causes at least one of: the notification to be sent to a verifying entity; restriction of functionality of the computing device until the verifying entity permits an increase in functionality of the computing device; restriction of functionality of the computing device until a determination is made that the indication is indicative of the computing device functioning as expected.

10. Apparatus comprising:
a sensor to measure a characteristic of an electric field distribution influenced by a hardware component of the apparatus, where the sensor is to send an indication of the characteristic to a verifying entity, to allow the verifying entity to determine, compared with a previously-determined electric field distribution associated with the apparatus, whether or not a change in the electric field distribution has occurred; and
a conductive element for modifying the electric field distribution to create a signature electric field distribution linked to processing circuitry of the apparatus.

11. The apparatus of claim 10 , where the sensor comprises a capacitor array for measuring the characteristic of the electric field distribution at different locations of the apparatus.

12. The apparatus of claim 11 , where the capacitor array comprises a plurality of capacitors distributed across the apparatus, and where the indication of the characteristic is indicative of a capacitance value associated with the capacitor at each of the different locations.

13. The apparatus of claim 10 , where the conductive element is included in the apparatus in a non-deterministic process to create a physically unclonable function for the signature electric field distribution.

14. A tangible machine-readable medium storing instructions which, when executed by at least one processor, cause the at least one processor to:
acquire an indication of an electrical parameter associated with a component for detecting a hardware status of a computing device;
determine, using processing circuitry and a conductive element for modifying an electric field distribution to create a signature electric field distribution linked to the processing circuitry, whether or not the indication meets a specified condition with respect to an estimated electrical parameter for the component based on an electric field distribution model for the computing device, where the specified condition is indicative of the hardware status of the computing device being as expected; and
cause a notification to be issued if the indication does not meet the specified condition.

Assignees

• Hewlett Packard Development Co

Inventors

• Plaquin David
• Huscroft Carey

Classifications

• G01R29/0814 Primary

  Field measurements related to measuring influence on or from apparatus, components or humans (EMC, EMI and similar testing in general G01R31/001), e.g. in ESD, EMI, EMC, EMP testing, measuring radiation leakage; detecting presence of micro- or radiowave emitters; dosimetry; testing shielding; measurements related to lightning · CPC title

• G01R31/312

  by capacitive methods · CPC title

• G01R29/14

  Measuring field distribution · CPC title

• G01R27/2605

  Measuring capacitance (capacitive sensors G01D5/24) · CPC title

• G01R31/002

  where the device under test is an electronic circuit · CPC title