Patent Description:
<CIT> discloses an electronic seal, which comprises a housing and a closure member cooperable with the housing to form a seal.

<CIT> discloses a monitoring device for security surveillance application, the device comprising an electromagnetic wave sensor for sensing electromagnetic wave from an external electromagnetic wave source.

<CIT> discloses an apparatus for securing connections between electronic components in order to detect tampering of the connections or components.

<CIT> discloses a user terminal, which comprises an encryption apparatus, a tamper detection system associated with the encryption apparatus and means for triggering the tamper detection system in response to tampering with the encryption apparatus.

Unscrupulous parties often target card-reading devices, such as point of sale devices, to capture card numbers, personal identification numbers (PINs), and other card data. Because of this, these devices often include mechanisms for detecting attempts to compromise their security, and when a breach is detected, often take actions to maintain the security of any information that may be stored on the device and/or prevent normal operation.

A problem to be solved by the invention is to increase the security level of electronic devices against tampering.

The problem is solved by an electronic device according to claim <NUM> and a method according to claim <NUM>.

Devices and methods for optical-based tamper detection using variable light characteristics are disclosed.

In one embodiment, the output light characteristic may vary in intensity, duty cycle, in state, etc. The output light characteristic may vary randomly or pseudo- randomly.

In one embodiment, the optoelectric controller may cause execution of a security action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount. The security action may include erasing secure information from a memory.

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

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

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

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

According to another embodiment, in an electronic device comprising a housing, a light source in the housing, a light detector in the housing, and an optoelectric controller, a method for optical-based tamper detection using variable light characteristics may include: (<NUM>) the light source emitting light having an output light characteristic that is variable, wherein the optoelectric controller controls the output light characteristic; (<NUM>) the light detector receiving the light emitted by the light source, the light received by the light detector having a received light characteristic; (<NUM>) the optoelectric controller comparing the received light characteristic to a known received light characteristic; and (<NUM>) the optoelectric controller causing execution of a security action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount.

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

In one embodiment, the security action may include erasing secure information from a memory.

For a more complete understanding of the present invention, the objects and advantages thereof, reference is now made to the following descriptions taken in connection with the accompanying drawings in which:.

Embodiments are directed to devices and methods for optical-based tamper detection by measuring the light from light source that is received at a light detector, in particular measuring an output light characteristic that may be varied. In one embodiment, the output light characteristic may vary by one or more of wavelength, intensity, duty cycle, and state.

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

The intensity of the light from one or more light sources may vary to create any color at any measurable intensity.

The duty cycle (e.g., on and off times) of the light source may be fixed, variable, random, pseudo-random, etc. The duty cycle may be manipulated to control intensity, to modulate the light source, etc..

The state (or stability) of the light source may vary as a function of time. For example, a light source may start at an intensity of <NUM>%, and ramp up to <NUM>% over a period of <NUM> msec. The optoelectric controller would 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 received at the receiver or light detector in a different fashion, or light is not received at all, a tamper event may be detected, and a security action may 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, then a tamper event may be detected, and a security action may be taken.

Several embodiments of the present invention and their advantages may be understood by referring to <FIG>.

Referring to <FIG>, in one embodiment, the device may include housing <NUM>, which may include, for example, one or more input device <NUM> (e.g., keypads, touchscreens, magnetic stripe readers, EMV chip readers (chip card readers), RF receivers, NFC receivers, etc.), one or more host computer processor <NUM> (e.g., secure processors, unsecure processors, etc.), memory <NUM>, display <NUM>, one or more light source <NUM>, one or more light receiver <NUM>, and one or more optoelectric controllers <NUM>. Housing <NUM> may include additional elements (e.g., circuit boards, integrated circuit chips, etc.) or fewer elements as is necessary and/or desired.

In one embodiment, host processor <NUM> and optoelectric controller <NUM> may be the same processor or controller.

In one embodiment, housing <NUM> may comprise multiple parts (e.g., a top part and a bottom part) that may be mechanically coupled (e.g., by fasteners, screws, clips, adhesives, welding, etc.). In one embodiment, housing <NUM> may be provided with one or more tamper detection devices (not shown), such as case open switches, security meshes, etc..

Although embodiments may be described in the context of a point of sale device, it should be recognized that the disclosure is not so limited. Embodiments have applicability in any device having a closed or semi-closed housing in which tamper detection is desired.

In one embodiment, light source(s) <NUM> and light receiver(s) <NUM> may be positioned within housing <NUM> so that light emitted from light source(s) <NUM> may be received by light receiver(s) <NUM> directly and/or indirectly (e.g., reflected off of the interior housing <NUM>, electrical and mechanical components provided therein, etc.). Light receiver(s) <NUM> may further be positioned to detect light from a light source (not shown) that is external to housing <NUM>, such as ambient light, a light source seeking to mimic light from light source(s) <NUM>, etc..

In one embodiment, light source(s) <NUM> and/or light receiver(s) <NUM> may be positioned near certain elements (e.g., optoelectric controller <NUM>, host processor <NUM>, memory <NUM>, input device(s) <NUM>, etc.) in order to detect a tamper event near these elements. Thus, embodiments provide a "self-protection" feature in which light source(s) <NUM>, light receiver(s) <NUM>, and/or optoelectric controller <NUM> may be located within an area of housing <NUM> that is being monitored. For example, if an attack seeks to disable the optoelectric tamper detection, the attack would be detected by the optoelectric tamper detection system. Similarly, if an attack sought to access a data interface between optoelectric controller <NUM> and host processor <NUM>, that attack would also be detected by the optoelectric tamper detection system.

In one embodiment, light source(s) <NUM> may include a single light source (e.g., a LED or a LED cluster), a multiple light source (e.g., two or more LEDs or LED clusters located within housing <NUM>), etc. The light source(s) <NUM> may be selected to produce a single wavelength, or a complex wavelength, and the intensity of the wavelength(s) produced may vary (e.g., between <NUM>% and <NUM>%, or as otherwise desired).

In one embodiment, light receiver <NUM> may include single light sensor with or without a filter, or multiple light sensors with or without filters.

In one embodiment, light receiver(s) <NUM> may be photocells (e.g., Cadmium -Sulfoselenide (CdS) photocells). For example, a change in the resistance of a photocell may be used to identify a change in light intensity. If the change in intensity varies outside of an expected amount, a tamper event may be detected.

In one embodiment, light receiver(s) <NUM> may be color detection or sensor modules.

In one embodiment, light source(s) <NUM> may provide light having a plurality of wavelengths (e.g., white light), or of a single wavelength (e.g., red, green, blue, infrared). Light source(s) <NUM> may be capable of producing light having different wavelengths at different times (e.g., red, blue, green, etc.). In another embodiment, ultraviolet (UV) light emitters and detectors may be used.

In another embodiment, light source(s) <NUM> may provide light having a plurality of wavelengths, and may be provided with a filter (not shown), such as a red filter, a blue filter, a green filter, etc. that results in light of a single wavelength. In one embodiment, the filter may be a gel-type filter.

In one embodiment, a plurality light sources <NUM> and filters may be provided to provide light of different wavelengths.

In one embodiment, light source(s) <NUM> may be LED light source(s), and may vary the intensity of emitted light.

In one embodiment, portions of the interior of housing <NUM> and/or the surface(s) of any components (e.g., mechanical and/or electrical components) contained therein may be provided with a coating (e.g., a reflective coating, a non-reflective coating, etc.) or cover (e.g., a reflective or non-reflective sheet of material) as is necessary and/or desired. For example, some or all of the interior of housing <NUM> may be painted with a coating to enhance its reflectiveness. Some or all components within housing <NUM> may be coated as is necessary and/or desired.

In one embodiment, optoelectric controller <NUM> may control at least one output light characteristic of the light source(s) <NUM>, such as the wavelength, intensity, duty cycle, and state of emitted light, and may further receive and process signal(s) from light receiver(s) <NUM>. Optoelectric controller <NUM> may activate light source(s) so as to produce a wavelength (e.g., if multiple light sources <NUM> each emitting (or filtered to emit) a particular wavelength are used, activating each light source <NUM> one at a time; if one light source <NUM> can emit multiple wavelengths, activating that light source <NUM> to emit light having a particular wavelength, and then light having a different wavelength).

In one embodiment, optoelectric controller <NUM> may cause light having different wavelengths to be emitted simultaneously. For example, optoelectric controller <NUM> may cause red light and green light to be emitted at the same time. The red and green light may be emitted from a single light source capable of generating multiple light wavelengths at the same time, or from separate light sources that may each generate one of the desired light wavelengths at a time.

Optoelectric controller <NUM> may control the wavelength of the light emitted by light source(s) <NUM> and, if necessary, filters, in a random or pseudo-random manner. By using a random or pseudo-random pattern, the pattern of light wavelengths that are emitted by the internal light sources may not readily be predicted or emulated by someone trying to circumvent this security feature.

For example, the series of wavelengths, the series of durations of illumination, the series of interstitial delay between illuminations, the intensity of the wavelengths, etc. may be random or pseudorandom.

In one embodiment, optoelectric controller <NUM> may control the intensity of the light emitted by light source(s) <NUM> in a random or pseudo-random manner so that a pattern of light intensity may not be readily predicted or emulated by someone trying to circumvent this security feature.

In one embodiment, light receiver(s) <NUM> may receive light emitted from light source(s) <NUM>, 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 the one or more received light characteristics differs from a known received light characteristic, such a baseline light characteristic measured in a secure environment or configuration, a tamper event may be detected. Examples of events that may cause the received light to not be within the predetermined tolerance level include the opening or breach of the housing, damage to the housing, the introduction of a foreign light source into the housing (e.g., in an attempt to defeat a light-based optical tamper detection mechanism), the movement or removal of a component within the housing (with or without a reflective coating), etc. If a tamper event is detected, optoelectric controller <NUM> and/ host computer processor <NUM> may implement one or more security actions (e.g., sound an alarm, power down, erase security-sensitive information in memory <NUM>, terminate network connections, etc.). For example, if a light wavelength other than the wavelength of light emitted from the light source is detected by the light receiver, the receiver may respond with a different-than-expected resistance. This different-than-expected resistance will result in a voltage signal that is not within the expected range, which may indicate a tamper event.

Similarly, if the intensity of the light received at the light detector differs from a known intensity, this difference may indicate a tamper event. The light detected by the light detector may be reflected off of a particular object within the device, including those that may or may not have been coated with a reflective material, or the light may be detected directly from the light source.

Referring to <FIG>, a method for optical-based tamper detection using variable light characteristics according to one embodiment.

In step <NUM>, when the device is in a known secure configuration, a baseline for wavelength, intensity, duty cycle, and/or state may be established. For example, a processor for the device may cause light of a certain wavelength, intensity, duty cycle, and/or state to be emitted by the light source, and may measure the wavelength, intensity, duty cycle, and/or state of light received at each of the one or more light receivers caused by the reflection of the light source off of objects within the interior of the housing. This information may then be stored in non-volatile memory. The processor may repeat this for each wavelength, intensity, duty cycle, and/or state and may store the information for each wavelength, intensity, duty cycle, and/or state. This process may cause multiple measurements to be performed and may average the results to establish a baseline.

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

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 and green light sources, and may record the results of the light received at the light detector.

In one embodiment, the baseline may be established at manufacture after the device has been fully assembled, when it has been repaired, or at any other suitable time. For example, the baseline may be established in a secure environment.

After the baseline is established, in step <NUM>, the processor may activate one or more light sources having one or more wavelength, intensity, duty cycle, and/or state. The timing with which the processor activates the light source may be periodic, pseudo-periodic, or random. In one embodiment, the processor may activate the one or more light sources using a pattern, in a pseudo-random manner, or in a random manner such that the wavelengths of the light emitted vary over time.

In one embodiment, the light source(s) may be activated for a short period of time. For example, the light sources may be activated for between <NUM>-<NUM> milliseconds. Other activation lengths may be used as is necessary and/or desired. The timing of the activation may also be based on a known pattern or sequence, or the timing may be based on a pseudo-random or random sequence.

In step <NUM>, light may be received at one or more light receivers within the device. In one embodiment, the light receiver may detect one or more wavelength, intensity, duty cycle, and/or state of the light.

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

In step <NUM>, if the light received at one or more light receiver(s) is within a predetermined tolerance level, the process of emitting, detecting, and comparing may be repeated.

If, in step <NUM>, the received light is not within a predetermined tolerance level, in step <NUM>, one or more security feature (e.g., sound an alarm, power down, erase memory, delete secret payment keys, terminate network connections, alert a host management (or similar) system, etc.) may be activated. Examples of events that may cause the received light to not be within the predetermined tolerance level include opening or breaching the housing, damage to the housing, the introduction of a foreign light source into the housing (e.g., in an attempt to defeat a light-based optical tamper detection mechanism), and the movement or removal of a component within the housing (with or without a reflective coati ng).

It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and sub-combinations of features described hereinabove and variations and modifications thereof which are not in the prior art. It should further be recognized that these embodiments are not exclusive to each other.

It will be readily understood by those persons skilled in the art that the embodiments disclosed here are susceptible to broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and foregoing description thereof, without departing from the substance or scope of the invention.

Claim 1:
Electronic device comprising:
a housing (<NUM>);
one or more input devices (<NUM>) comprising at least one of a magnetic stripe reader, an EMV chip reader, an RF receiver, and an NFC receiver within the housing (<NUM>);
a light source (<NUM>) within the housing (<NUM>) configured to emit light having an output light characteristic that is variable;
wherein the output light characteristic varies in wavelength and/or intensity;
a light detector (<NUM>) within the housing (<NUM>) configured to directly receive the light emitted by the light source (<NUM>), the light received by the light detector (<NUM>) having a received light characteristic; and
an optoelectric controller (<NUM>) in communication with the light source (<NUM>) and the light detector (<NUM>), wherein the optoelectric controller (<NUM>) controls the output light characteristic and compares the received light characteristic to a known received light characteristic and causes execution of a security action in response to the received light characteristic and the known received light characteristic differing by a predetermined amount;
wherein the electronic device is a point of sale device.