Devices and methods for optical-based tamper detection using variable light properties

Abstract

The present application discloses an apparatus and method for optical-based tamper detection using variable light characteristics. In one embodiment, an electronic device may include: a housing; a light source in the housing, the light source configured to emit light having variable output light characteristics; a light detector in the housing, the light detector configured to receive light emitted by the light source, the light received by the light detector having received light characteristics; and a photoelectric controller in communication with the light source and the light detector, wherein the photoelectric controller controls the output light characteristics and compares the received light characteristics with known received light characteristics.

Description

Technical Field

[0001] The present disclosure generally relates to devices and methods for optical-based tamper detection using variable light properties. Background Art

[0002] Criminals often target card reading devices, such as point-of-sale devices, to capture card numbers, personal identification numbers (PINs), and other card data. As a result, these devices often include mechanisms for detecting attempts to compromise their security, and when a compromise is detected, often take action to maintain the security of any information that may be stored on the device and / or prevent normal operation. Summary of the invention

[0003] Devices and methods for optical-based tamper detection using variable light characteristics are disclosed. In one embodiment, an electronic device may include: a housing; a light source within the housing, the light source configured to emit light having variable output light characteristics; a light detector within the housing, the light detector configured to receive light emitted by the light source, the light received by the light detector having received light characteristics; and an optoelectronic controller in communication with the light source and the optoelectronic controller, wherein the optoelectronic controller controls the output light characteristics and compares the received light characteristics with known received light characteristics.

[0004] In one embodiment, the output light characteristics may vary in intensity, duty cycle, wavelength, state, etc. The output light characteristics may vary randomly or pseudo-randomly.

[0005] In one embodiment, the photoelectric controller may cause a security action to be performed in response to the received light characteristic differing by a predetermined amount from a known received light characteristic. The security action may include erasing security information from a memory.

[0006] In one embodiment, the device may include multiple components within a housing. Some of the components may be covered with a reflective coating.

[0007] In one embodiment, the light source and / or light detector may be positioned to detect breach of the housing.

[0008] In one embodiment, the known received light characteristic may be based on the output light characteristic.

[0009] In one embodiment, the electronic device may be a point of sale device.

[0010] According to another embodiment, in an electronic device including a shell, a light source in the shell, a light detector in the shell, and a photoelectric controller, a method for optical-based tamper detection using variable light characteristics may include: (1) the light source emits light with variable output light characteristics, wherein the photoelectric controller controls the output light characteristics; (2) the light detector receives light emitted by the light source, the light received by the light detector having a received light characteristic; (3) the photoelectric controller compares the received light characteristic with a known received light characteristic; and (4) the photoelectric controller causes execution of a security action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount.

[0011] In one embodiment, the output light characteristics may vary in intensity, duty cycle, wavelength, state, etc. The output light characteristics may vary randomly or pseudo-randomly.

[0012] In one embodiment, the security action may include erasing the security information from the memory.

[0013] In one embodiment, the light source and / or light detector may be positioned to detect breach of the housing.

[0014] In one embodiment, the known received light characteristic may be based on the output light characteristic. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] For a more complete understanding of the present invention, its objects and advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0016] Figure 1 A system for optical-based tamper detection using variable light properties according to one embodiment is depicted; and

[0017] Figure 2 A method of optical-based tamper detection using variable light properties according to one embodiment is described. DETAILED DESCRIPTION

[0018] Embodiments are directed to devices and methods for optical-based tamper detection by measuring light received at a light detector from a light source, particularly measuring output light characteristics that can vary. In one embodiment, the output light characteristics can vary by one or more of wavelength, intensity, duty cycle, and state.

[0019] For example, the wavelength of the light source can vary in any of the visible spectrum, infrared spectrum, ultraviolet spectrum, etc. The wavelength of the light source can be varied by changing the wavelength of the light source from one measurement value to another. In one embodiment, the wavelength of the light source can be varied over time during a single measurement.

[0020] The intensity of light from one or more light sources can be varied to produce any color at any measurable intensity.

[0021] The duty cycle (eg, on and off time) of the light source can be fixed, variable, random, pseudo-random, etc. The duty cycle can be manipulated to control intensity, modulate the light source, etc.

[0022] The state (or stability) of the light source can change as a function of time. For example, the light source can start at 50% intensity and gradually rise to 100% over a period of 250 milliseconds. The photoelectric controller will expect to measure a comparable change in the intensity of the light received at the receiver or light detector. If the intensity of the light is received at the receiver or light detector in a different manner, or no light is received at all, a tamper event can be detected and security action can be taken. Similarly, if the wavelength or duty cycle of the light received at the receiver or detector is different from that of the light source, a tamper event can be detected and security action can be taken.

[0023] By reference Figure 1-Figure 2 Several embodiments of the present invention and their advantages are appreciated.

[0024] Reference Figure 1 In one embodiment, the device may include a housing 100 that may include, for example, one or more input devices 110 (e.g., a keypad, a touch screen, a magnetic stripe reader, an EMV chip reader, an RF receiver, an NFC receiver, etc.), one or more host computer processors 120 (e.g., a secure processor, an unsecure processor, etc.), a memory 130, a display 140, one or more light sources 150, one or more light receivers 160, and one or more photoelectric controllers 170. The housing 100 may include additional elements (e.g., circuit boards, integrated circuit chips, etc.) or fewer elements as needed and / or desired.

[0025] In one embodiment, the host processor 120 and the optoelectronic controller 170 may be the same processor or controller.

[0026] In one embodiment, the housing 100 may include multiple parts (e.g., a top and a bottom) that may be mechanically coupled (e.g., by fasteners, screws, clips, adhesives, welding, etc.). In one embodiment, the housing 100 may be provided with one or more tamper detection devices (not shown), such as a case opening switch, a safety net, etc.

[0027] Although embodiments may be described in the context of a point of sale device, it should be appreciated that the present disclosure is not limited thereto.Embodiments may be applied in any device having a closed or semi-closed housing in which tamper detection is desired.

[0028] In one embodiment, light source(s) 150 and light receiver(s) 160 may be positioned within housing 100 such that light emitted from light source(s) 150 may be received by light receiver(s) 160 directly and / or indirectly (e.g., reflected from internal housing 110, electrical and mechanical components disposed in internal housing 110, etc.). Light receiver(s) 160 may be further positioned to detect light from light sources (not shown) external to housing 100, such as ambient light, light sources that seek to mimic light from light source(s) 150, etc.

[0029] In one embodiment, (one or more) light sources 150 and / or (one or more) light receivers 160 can be positioned near certain elements (e.g., optoelectronic controller 170, host processor 120, memory 130, (one or more) input devices 110, etc.) to detect tampering events near these elements. Thus, an embodiment provides a "self-protection" feature in which (one or more) light sources 150, (one or more) light receivers 160 and / or optoelectronic controller 170 can be located within the area of ​​the monitored housing 100. For example, if an attack attempts to disable optoelectronic tamper detection, the attack will be detected by the optoelectronic tamper detection system. Similarly, if an attack attempts to access the data interface between the optoelectronic controller 170 and the host processor 120, the attack will also be detected by the optoelectronic tamper detection system.

[0030] In one embodiment, the light source(s) 150 may include a single light source (e.g., an LED or LED cluster), multiple light sources (e.g., two or more LEDs or LED clusters located within the housing 100), etc. The light source(s) 150 may be selected to produce a single wavelength or a composite wavelength, and the intensity of the produced wavelength(s) may vary (e.g., between 10% and 100%, or other range as desired).

[0031] In one embodiment, the light receiver 160 may include a single light sensor with or without light filters, or multiple light sensors with or without light filters.

[0032] In one embodiment, the optical receiver(s) 160 may be a photocell (e.g., a cadmium-sulfenyl selenide (CdS) photocell). For example, a change in the resistance of the photocell may be used to identify a change in light intensity. If the change in intensity exceeds an expected amount, a tampering event may be detected.

[0033] In one embodiment, the light receiver(s) 160 may be a color detection or sensor module.

[0034] In one embodiment, the light source(s) 150 may provide light having multiple wavelengths (e.g., white light) or a single wavelength (e.g., red, green, blue, infrared). The light source(s) 150 may be capable of generating light having different wavelengths (e.g., red, blue, green, etc.) at different times. In another embodiment, an ultraviolet (UV) light emitter and detector may be used.

[0035] In another embodiment, the light source(s) 150 may provide light having multiple wavelengths and may be provided with filters (not shown), such as red filters, blue filters, green filters, etc., to produce light of a single wavelength. In one embodiment, the filters may be gel-type filters.

[0036] In one embodiment, multiple light sources 150 and filters may be provided to provide light of different wavelengths.

[0037] In one embodiment, the light source(s) 150 may be LED light source(s), and may vary the intensity of the emitted light.

[0038] In one embodiment, as needed and / or desired, a portion of the interior of housing 100 and / or the surface(s) of any components (e.g., mechanical and / or electrical components) housed therein may be provided with a coating (e.g., a reflective coating, a non-reflective coating, etc.) or a covering (e.g., a sheet of reflective or non-reflective material). For example, some or all of the interior of housing 100 may be coated to enhance its reflectivity. Some or all of the components within housing 100 may be coated as needed and / or desired.

[0039] In one embodiment, the opto-controller 170 may control at least one output light characteristic of the light source(s) 150, such as wavelength, intensity, duty cycle, and state of the emitted light, and may further receive and process the signal(s) from the optical receiver(s) 160. The opto-controller 170 may activate the light source(s) to produce a wavelength (e.g., if multiple light sources 150 are used that each emit (or are filtered to emit) a specific wavelength, then activate each light source 150 one at a time; if one light source 150 can emit multiple wavelengths, then activate the light source 150 to emit light having a specific wavelength, and then emit light having a different wavelength).

[0040] In one embodiment, the photoelectric controller 170 can cause light with different wavelengths to be emitted simultaneously. For example, the photoelectric controller 170 can cause red light and green light to be emitted simultaneously. The red light and green light can be emitted from a single light source that can generate multiple light wavelengths simultaneously, or from separate light sources that can each generate one desired light wavelength at a time.

[0041] The photoelectric controller 170 can control the wavelength of light emitted by (one or more) light sources 150 in a random or pseudo-random manner and, if necessary, can control the filter. By using a random or pseudo-random pattern, a person trying to circumvent this security feature may not easily predict or imitate the pattern of light wavelengths emitted by the internal light source.

[0042] For example, a series of wavelengths, a series of illumination durations, a gap delay between a series of illuminations, wavelength intensities, etc. can be random or pseudo-random.

[0043] In one embodiment, the photoelectric controller 170 may control the intensity of light emitted by the light source(s) 150 in a random or pseudo-random manner such that the pattern of light intensity may not be easily predicted or mimicked by a person attempting to circumvent this safety feature.

[0044] In one embodiment, the (one or more) optical receivers 160 may receive light emitted from the (one or more) light sources 150, and may indicate or determine one or more received light characteristics (e.g., wavelength, intensity, duty cycle, and state) of the received light. In one embodiment, if one or more received light characteristics are different from known received light characteristics, such as baseline light characteristics measured in a secure environment or configuration, a tampering event may be detected. Examples of events that may cause the received light to be outside the predetermined tolerance level include: opening or breaking the housing, damaging the housing, introducing an external light source into the housing (e.g., attempting to destroy a light-based optical tampering detection mechanism), moving or removing components within the housing (with or without a reflective coating), etc. If a tampering event is detected, the photoelectric controller 170 and / or the host computer processor 120 may implement more security actions (e.g., sound an alarm, power off, erase security-sensitive information in the memory 130, terminate the network connection, etc.). For example, if the optical receiver detects a wavelength of light that is different from the wavelength of light emitted from the light source, the receiver may respond with a resistance different from that expected. This resistance different from that expected will result in a voltage signal that is not within the expected range, which may indicate a tampering event.

[0045] Similarly, if the intensity of the light received at the light detector differs from the known intensity, the difference may indicate a tampering event. The light detected by the light detector may be reflected from specific objects within the device (including those that may or may not be coated with reflective materials), or the light may be detected directly from the light source.

[0046] Reference Figure 2 , according to one embodiment, a method for optical-based tamper detection using variable light properties.

[0047] In step 205, when the device is in a known safe configuration, a baseline of wavelength, intensity, duty cycle and / or state can be established. For example, the processor of the device can cause the light source to emit light of a specific wavelength, intensity, duty cycle and / or state, and can measure the wavelength, intensity, duty cycle and / or state of the light received at each of the one or more light receivers due to the reflection of the light source by the object inside the shell. This information can then be stored in a non-volatile memory. The processor can repeat this operation for each wavelength, intensity, duty cycle and / or state, and can store information for each wavelength, intensity, duty cycle and / or state. This process can result in multiple measurements being performed, and the results may be averaged to establish a baseline.

[0048] For example, in one embodiment, if the system employs four light sensors and two light sources, a set of measurements may include eight readings. That is, each sensor will be read twice (e.g., the first time when the first light source is turned on, and the second time when the second light source is turned on). In one embodiment, the readings may be repeated several times (e.g., ten times) and then averaged, which will provide an average value for each sensor / source combination.

[0049] In one embodiment, the processor may do this for each light source, for each wavelength, intensity, duty cycle, each state, etc. For example, the processor may activate both the red light source and the green light source and may record the results of the light received at the light detector.

[0050] In one embodiment, the baseline may be established at manufacturing after the device is fully assembled, when it is repaired, or at any other suitable time. For example, the baseline may be established in a secure environment.

[0051] After establishing the baseline, in step 210, the processor may activate one or more light sources having one or more wavelengths, intensities, duty cycles, and / or states. The timing of the processor activating the light sources may be periodic, pseudo-periodic, or random. In one embodiment, the processor may activate one or more light sources using a pattern in a pseudo-random manner or in a random manner such that the wavelength of the emitted light varies over time.

[0052] In one embodiment, the light source(s) may be activated for a short period of time. For example, the light source may be activated for between 60-250 milliseconds. Other activation lengths may be used as needed and / or desired. The timing of activation may also be based on a known pattern or sequence, or the timing may be based on a pseudo-random or random sequence.

[0053] In step 215, light may be received at one or more light receivers within the device. In one embodiment, the light receivers may detect one or more wavelengths, intensities, duty cycles, and / or states of the light.

[0054] In step 220, the wavelength, intensity, duty cycle and / or state of light received at one or more light receivers may be compared to a baseline, or to a sequence or pattern of emitted wavelengths, intensities, duty cycles and / or states.

[0055] In step 225, if the light received at the one or more light receivers is within a predetermined tolerance level, the process of transmitting, detecting, and comparing may be repeated.

[0056] If the received light is not within a predetermined tolerance level in step 225, then in step 230, one or more security functions may be activated (e.g., sound an alarm, remove power, erase memory, delete secret payment keys, terminate network connections, alert a host management (or similar) system, etc.). Examples of events that may cause the received light to be not within a predetermined tolerance level include opening or breaking the housing, damaging the housing, introducing a foreign light source into the housing (e.g., in an attempt to defeat a light-based optical tamper detection mechanism), and movement or removal of components within the housing (with or without a reflective coating).

[0057] The following documents are incorporated herein by reference in their entirety: US Patent Application Serial No. 15 / 900,317; US Patent Application Serial No. 14 / 802,305; and US Provisional Patent Application Serial No. 62 / 027,890.

[0058] Those skilled in the art will recognize that the present invention is not limited to what has been specifically shown and described above. On the contrary, the scope of the present invention includes combinations and sub-combinations of the features described above and their variations and modifications, which are not in the prior art. It should also be recognized that these embodiments are not mutually exclusive.

[0059] Those skilled in the art will readily appreciate that the embodiments disclosed herein are susceptible to widespread use and application. Many embodiments and adaptations of the invention other than those described herein and many variations, modifications and equivalent arrangements will be apparent or reasonably suggested based on the invention and its foregoing description without departing from the spirit or scope of the invention.

[0060] Therefore, although the present invention has been described in detail with respect to exemplary embodiments of the present invention, it should be understood that the present disclosure is only illustrative and exemplary of the present invention, and is provided to provide a feasible disclosure of the present invention. Therefore, the foregoing disclosure is not intended to explain or limit the present invention, or to exclude any other such embodiments, adaptations, variations, modifications or equivalent arrangements.

Claims

1. A point of sale device comprising: case; at least one of a magnetic stripe reader, an EMV chip reader, an RF receiver, and an NFC receiver within the housing; a light source within the housing, the light source configured to emit light having a variable output light characteristic, wherein the output light characteristic varies in intensity; a light detector within the housing, the light detector being configured to directly receive light emitted by the light source, the light received by the light detector having a received light characteristic; as well as a photoelectric controller in communication with the light source and the light detector, wherein the photoelectric controller controls the output light characteristic, compares the received light characteristic with a known received light characteristic, and causes execution of a safety action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount.

2. The point of sale device of claim 1, wherein the output light characteristic also varies in duty cycle.

3. The point of sale device of claim 1, wherein the output light characteristic also varies in wavelength.

4. The point of sale device of claim 1, wherein the output light characteristic also varies in state.

5. The point of sale device of claim 1, wherein the output light characteristic varies randomly or pseudo-randomly.

6. The point of sale device of claim 1, wherein the security action comprises at least one of erasing security information from memory, sounding an alarm, powering off the point of sale device, and terminating a network connection.

7. The point of sale device of claim 1, wherein the light source or the light detector is positioned to detect tampering with the housing.

8. The point of sale device of claim 1, wherein the known received light characteristic is based on an output light characteristic of light emitted by the light source when the point of sale device is in a secure environment.

9. The point of sale device of claim 1 , wherein at least a portion of an interior of the housing is provided with a reflective coating, and the light detector is further configured to indirectly receive light emitted by the light source and reflected from the at least a portion of the interior of the housing.

10. The point of sale device of claim 1 , further comprising a plurality of components within the housing, wherein at least some of the plurality of components are covered by a reflective coating, and the light detector is further configured to indirectly receive light emitted by the light source and reflected from the at least some of the plurality of components.

11. The point of sale device of claim 1 , wherein the light source comprises at least one ultraviolet light emitter.

12. The point of sale device of claim 1, wherein the light source comprises a filter.

13. The point of sale device of claim 1, wherein the light source is configured to simultaneously emit light having different wavelengths.

14. A method for optical-based tamper detection using variable light properties, comprising: In a point of sale device, the point of sale device includes a housing, at least one of a magnetic stripe reader, an EMV chip reader, an RF receiver, and an NFC receiver within the housing, a light source within the housing, a light detector within the housing, and a photoelectric controller within the housing: The light source emits light having a variable output light characteristic, wherein the output light characteristic varies in intensity, and wherein the optoelectronic controller controls the output light characteristic; The light detector directly receives the light emitted by the light source, and the light received by the light detector has the received light characteristic; The photoelectric controller compares the received light characteristics with known received light characteristics; and The photoelectric controller causes execution of a safety action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount.

15. The method of claim 14, wherein the output light characteristic also varies in duty cycle.

16. The method of claim 14, wherein the output light characteristic also varies in wavelength.

17. The method of claim 14, wherein at least a portion of the interior of the housing is provided with a reflective coating, and the light detector is further configured to indirectly receive light emitted by the light source and reflected from the at least a portion of the interior of the housing.

18. The method according to claim 14 further includes a plurality of components within the housing, wherein at least some of the plurality of components are covered with a reflective coating, and the light detector is further configured to indirectly receive light emitted by the light source and reflected from at least some of the plurality of components.

19. The method of claim 14, wherein the light source comprises at least one ultraviolet light emitter.

20. The method of claim 14, wherein the light source comprises a filter.

21. The method of claim 14, comprising the light source emitting light having different wavelengths simultaneously.

22. The method of claim 14, wherein the output light characteristics vary randomly or pseudo-randomly.

23. The method of claim 14, wherein the security action comprises at least one of erasing security information from memory, sounding an alarm, powering off the point of sale device, and terminating a network connection.

24. The method of claim 14, wherein the light source or the light detector is positioned to detect damage to the housing.

25. The method of claim 14, wherein the known received light characteristic is based on an output light characteristic of light emitted by the light source when the point of sale device is in a secure environment.

26. An electronic device comprising: case; a light source within the housing, the light source configured to emit light having a variable output light characteristic, wherein the output light characteristic varies in intensity; a light detector within the housing, the light detector configured to receive the light emitted by the light source, the light received by the light detector having a received light characteristic including intensity; as well as a photoelectric controller in communication with the light source and the light detector, wherein the photoelectric controller controls the output light characteristic, compares the received light characteristic with a known received light characteristic, and causes execution of a safety action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount.

27. The electronic device of claim 26, wherein the light detector comprises a phototube configured to identify a change in light intensity of the received light.

28. The electronic device of claim 27, wherein the photocell is a cadmium-sulfenyl selenide (CdS) photocell.

29. The electronic device according to claim 27, wherein a change in resistance of the photoelectric tube is used to identify a change in light intensity of the received light.

30. The electronic device of claim 26, wherein the known received light characteristic is based on an output light characteristic of light emitted by the light source when the electronic device is in a secure environment.

31. A method for optical-based tamper detection using variable light properties, comprising: In an electronic device, the electronic device comprises a housing, a light source in the housing, a light detector in the housing, and a photoelectric controller in the housing: The light source emits light having a variable output light characteristic, wherein the optoelectronic controller controls the output light characteristic, and the output light characteristic varies in intensity; the light detector receiving the light emitted by the light source, the light received by the light detector having a received light characteristic including intensity, wherein the light detector is configured to identify changes in intensity; The photoelectric controller compares the received light characteristic with a known received light characteristic; and The photoelectric controller causes execution of a safety action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount.

32. The method of claim 31, wherein the light detector comprises a phototube configured to identify changes in light intensity of the received light.

33. The method of claim 32, wherein the photocell is a cadmium-sulfenyl selenide (CdS) photocell.

34. The method of claim 32, wherein a change in resistance of the photoelectric tube is used to identify a change in light intensity of the received light.

35. The method of claim 31, wherein the known received light characteristic is based on an output light characteristic of light emitted by the light source when the electronic device is in a secure environment.

36. The method of claim 31, wherein the output light characteristics also vary in duty cycle, wavelength and / or state.

37. The method of claim 31 , wherein the output light characteristics vary randomly or pseudo-randomly.

38. The method of claim 31, wherein the security action comprises erasing security information from a memory.

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