Mitigating resource usage attacks

Abstract

A method for mitigating resource usage attacks by a transmitter device (1) on a receiver device (2) over a wireless interface (4) is provided. The method is performed by a receiver device (2). The method comprises: receiving (40) a header transmission from a transmitter device (1), the header (21) forming part of a radio frame (20), the header (21) comprising an indicator of a size of a subsequent transmission of a payload (22) in the radio frame (20), where the receiving comprises performing a header measurement, the header measurement being a measurement of a received signal strength of the header transmission; performing (42) a payload measurement, the payload measurement being a measurement of the received signal strength measurement when a payload (22) of the radio frame (20) is expected to be received; determining (44) that the payload measurement is below a threshold; and releasing (46) resources for receiving the payload.

Description

Technical Field

[0001] This disclosure relates to the field of resource use attacks carried out by a transmitter via a wireless interface, and more particularly to mitigating resource use attacks carried out by a transmitter device in a receiver device. Background Technology

[0002] In wireless communication, receiver devices eavesdrop on incoming communications. When such eavesdropping occurs on random access transmissions, there is a risk that the transmitter can exploit the random access to cause the receiver device to waste resources. For example, such a resource-use attack can occur by an attacker using a transmitter device to send a radio frame consisting only of a header, where the header indicates that a long payload will be sent in the remainder of the radio frame. Then, the payload is never sent.

[0003] The receiver device receives the header of a radio frame and then prepares to receive the payload. However, as mentioned above, an attacker never sends the payload. This results in a waste of resources in the receiver while it listens for and attempts to decode the received radio signals. An attacker can repeat the attack multiple times to create a cumulative waste of resources in the receiver.

[0004] Currently, receiver devices have no way to mitigate the impact of such resource usage attacks while still being able to receive legitimate random access communications. Summary of the Invention

[0005] One objective is to provide methods for detecting and mitigating attacks on the resource usage of receiver devices via wireless interfaces.

[0006] In some aspects, the embodiments described herein relate to a method for mitigating resource usage attacks by a transmitter device against a receiver device via a wireless interface, the method being performed by the receiver device, the method comprising: receiving a header transmission from the transmitter device, the header forming part of a wireless frame, the header including an indicator of the size of a subsequent transmission of a payload in the wireless frame, wherein receiving includes performing a header measurement, the header measurement being a measurement of the signal strength of the received header transmission; performing a payload measurement, the payload measurement being a measurement of a received signal strength measurement when the payload of the wireless frame is expected to be received, wherein the expectation of when the payload will be received is based on the size indicated in the header; determining that the payload measurement is below a threshold; and releasing resources used for receiving the payload.

[0007] In some aspects, the embodiments described herein relate to a method in which a payload measurement is performed repeatedly over an indicated transmission time until the payload measurement value is lower than the header measurement value by a threshold amount.

[0008] In some aspects, the implementations described herein relate to methods in which releasing resources includes ending attempts to decode the payload.

[0009] In some aspects, the embodiments described herein relate to methods in which releasing resources includes setting a receiver device to a state where it is ready to receive a new header.

[0010] In some respects, the implementation described herein relates to a method in which the wireless interface is a short-range wireless interface.

[0011] In some respects, the implementations described herein relate to methods in which the wireless interface conforms to any communication standard according to the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4.

[0012] In some aspects, the implementations described herein relate to methods in which the wireless interface conforms to Bluetooth, Bluetooth Low Energy (BLE), or Z-Wave.

[0013] In some aspects, the implementation described herein relates to a method in which the threshold is determined relative to a header measurement.

[0014] In some aspects, the implementation described herein relates to a method in which the threshold is a static value.

[0015] In some aspects, the embodiments described herein relate to a receiver device for mitigating resource usage attacks by a transmitter device on a receiver device via a wireless interface, the receiver device comprising: a processing circuitry system; and a memory circuitry system storing instructions that, when executed by the processing circuitry system, cause the receiver device to: receive a header transmission from the transmitter device, the header forming part of a wireless frame, the header including an indicator of the size of a subsequent transmission of a payload in the wireless frame, wherein receiving includes performing a header measurement, the header measurement being a measurement of the signal strength of the received header transmission; performing a payload measurement, the payload measurement being a measurement of the received signal strength when the payload of the wireless frame is expected to be received, wherein the expectation of when the payload will be received is based on the size indicated in the header; determining that the payload measurement is below a threshold; and releasing resources for receiving the payload.

[0016] In some aspects, the embodiments described herein relate to a receiver device that further includes instructions, when executed by a processing circuitry system, to cause the content receiver device to perform the following operation: repeating payload measurements multiple times during an indicated transmission time until the payload measurement value is lower than the header measurement value by a threshold amount.

[0017] In some aspects, the embodiments described herein relate to receiver devices, wherein the instructions for releasing resources include instructions that, when executed by the processing circuitry system, cause the content receiver device to terminate an attempt to decode a payload.

[0018] In some aspects, the embodiments described herein relate to a receiver device, wherein the instruction to release resources includes, when executed by the processing circuitry system, an instruction to cause the content receiver device to perform the following operation: setting the receiver device to a state in which it is ready to receive new headers.

[0019] In some respects, the embodiments described herein relate to receiver devices, wherein the wireless interface is a short-range wireless interface.

[0020] In some respects, the embodiments described herein relate to receiver devices in which the wireless interface conforms to any communication standard according to the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4.

[0021] In some aspects, the embodiments described herein relate to receiver devices in which the wireless interface conforms to Bluetooth or Bluetooth Low Energy (BLE).

[0022] In some aspects, the embodiments described herein relate to receiver devices in which the threshold is determined relative to header measurements.

[0023] In some aspects, the embodiments described herein relate to receiver devices, wherein the threshold is a static value.

[0024] In some aspects, the embodiments described herein relate to a computer program for mitigating resource usage attacks by a transmitter device against a receiver device via a wireless interface. The computer program includes computer program code that, when executed on the receiver device, causes the receiver device to: receive a header transmission from the transmitter device, the header forming part of a wireless frame, the header including an indicator of the size of a subsequent transmission of a payload in the wireless frame, wherein receiving includes performing a header measurement, which is a measurement of the signal strength of the received header transmission; performing a payload measurement, which is a measurement of the received signal strength when the payload of the wireless frame is expected to be received, wherein the expectation of when the payload will be received is based on the size indicated in the header; determining that the payload measurement is below a threshold; and releasing resources used for receiving the payload.

[0025] In some aspects, the embodiments described herein relate to a computer program product including a computer program and a computer-readable device including a non-transitory memory storing the computer program.

[0026] Generally, unless otherwise expressly defined herein, all terms used in the claims shall be interpreted according to their ordinary meaning in the art. Unless otherwise expressly stated, all references to “a / an / the element, device, component, apparatus, step, etc.” shall be explicitly interpreted as referring to at least one instance of that element, device, component, apparatus, step, etc. Unless expressly stated otherwise, the steps of any method disclosed herein need not be performed in the exact order disclosed. Attached Figure Description

[0027] The aspects and implementation methods will now be described by way of example with reference to the accompanying drawings, in which:

[0028] Figure 1 This is a schematic diagram illustrating an environment in which the embodiments proposed herein can be applied;

[0029] Figure 2 This shows what can be applied to Figure 1 A schematic diagram of the structure of a wireless frame in an environment;

[0030] Figures 3A to 3B This is a schematic diagram showing the signal strength of a normal wireless frame and an attacker's wireless frame;

[0031] Figure 4 This is a flowchart illustrating a method for mitigating attacks on the resource usage of a receiver device by a transmitter device through a wireless interface;

[0032] Figure 5 It is shown Figure 1 A schematic diagram of the components of the receiver device; and

[0033] Figure 6 An example of a computer program product that includes a computer-readable device is shown. Detailed Implementation

[0034] The various aspects of this disclosure will be described more fully below with reference to the accompanying drawings, which illustrate certain embodiments of the invention. However, these aspects may be embodied in many different forms and should not be construed as limiting; rather, these embodiments are provided by way of example so that this disclosure will be comprehensive and complete, and will fully convey the scope of all aspects of the invention to those skilled in the art. Throughout the description, the same reference numerals refer to the same elements.

[0035] According to the implementation described herein, when an indicated payload is expected to be received, the receiver device detects a resource usage attack via the wireless interface by detecting a drop in the signal level received after the header has already been received. When a resource usage attack is detected, resources used for receiving the payload are released, thereby effectively reducing the impact of such attacks.

[0036] Figure 1 This is a schematic diagram illustrating an environment in which the embodiments proposed herein can be applied. The receiver device 2 is a device capable of receiving short-range communications via the wireless interface 4 for any suitable purpose. Therefore, the wireless interface 4 can be a short-range communication interface, for example, conforming to any communication standard according to IEEE 802.15.4, such as Thread, ZigBee, WirelessHART, Matter, etc. Alternatively or additionally, the wireless interface 4 conforms to Bluetooth, Bluetooth Low Energy (BLE), or Z-wave. The short-range communication interface can be an interface supporting local point-to-point communication, which can optionally be extended to a mesh network. It should be noted that the receiver device 2 can also act as a transmitter; however, for the purposes of this document, the receiver device 2 is described in terms of its ability to receive short-range wireless communications and how an attacker with the transmitter device 1 could exploit the wireless interface 4 for resource utilization attacks.

[0037] Receiver device 2 listens for communication initiated by transmitter device 1 through wireless interface 4. It should be noted that wireless interface 4 supports random access, because transmitter device 1 can initiate communication 1 that receiver device 2 will receive and process without receiver device 2 notifying transmitter device 1 that it is allowed to send.

[0038] Figure 2 This shows what can be applied to Figure 1 This is a schematic diagram of the structure of a wireless frame 20 in an environment. The wireless frame 20 includes a header 21 and a payload 22. Among other fields (not shown), the header 21 also includes an indicator 23 indicating the size of subsequent transmissions of the payload 22. The payload 22 can be much larger than the header 21. For illustrative purposes only, in Zigbee, for example, the header is one byte long, while the payload is 3 to 127 bytes long.

[0039] Figures 3A to 3B This is a schematic diagram illustrating the signal strength of a normal wireless frame and an attacker's wireless frame. The horizontal axis indicates time, and the vertical axis 15 indicates signal strength, for example as the Received Signal Strength Indicator (RSSI) at the receiver side, such as that received by receiver device 2. Between time t0 and t1, the header is received. Between time t1 and t2, the payload is expected to be received, and the size of the payload is indicated in the header.

[0040] exist Figure 3A The diagram shows the normal signal strength curve 10 for a normal radio frame. The normal signal strength curve 10 remains high throughout the entire duration of the radio frame, and remains high in both the header reception period (times t0 to t1) and the payload reception period (times t1 to t2).

[0041] Looking at it now Figure 3B The image shows an attacker signal strength curve 11, which indicates the signal strength when a resource usage attack occurs. In this case, the attacker signal strength curve 11 remains high during header reception (times t0 and t1). However, during payload reception (times t1 to t2), the transmitter device 1 does not transmit a signal.

[0042] Figure 4 This is a flowchart illustrating a method for mitigating resource usage attacks by a transmitter device 1 against a receiver device 2 via a wireless interface 4. The method is implemented in receiver device 2 (such as...) Figure 1 Executed in the receiver device 2).

[0043] Wireless interface 4 can, for example, comply with any communication standard according to IEEE 802.15.4, such as Thread, ZigBee, Wireless Heart, Matter, etc. Alternatively or additionally, wireless interface 4 can comply with Bluetooth or BLE.

[0044] In header reception step 40, receiver device 2 receives a header transmission from transmitter device 1. The header 21 forms part of radio frame 20. Receiver device 2 decodes the header and interprets its contents. Header 21 includes an indicator of the size (e.g., in bytes) of the subsequent transmission of payload 22 in radio frame 20. Reception includes performing a header measurement, which is a measurement of the signal strength of the received header transmission. The header measurement may be an RSSI measurement.

[0045] In the payload measurement step 42, the receiver device 2 performs a payload measurement, which is a measurement of the received signal strength when the payload 22 of the radio frame 20 is expected to be received. The payload measurement may be an RSSI measurement. The expectation of when the payload will be received can be based on the magnitude indicated in the header to ensure that the measurement occurs after the header transmission is complete and before the payload has finished to be received.

[0046] In the conditional payload measurement low step 44, receiver device 2 evaluates the payload measurement. If the payload measurement value is low, for example by determining that the payload measurement value is below a threshold, this indicates a resource usage attack (where transmitter device 1 has not transmitted the payload indicated in the header). The method then proceeds to the resource release step 46. Otherwise, when the payload measurement value is not low, the method proceeds to an optional measurement further step 45, or, if measurement further step 45 is not performed, the method terminates. The threshold can be determined relative to the header measurement value (e.g., x% of the header measurement value). Alternatively, the threshold can be a static value, such as -y dBm.

[0047] In the optional conditional measurement further step 45, the receiver device 2 determines whether to perform more payload measurements. For example, the payload measurement may be repeated multiple times during an indicated transmission time until the payload measurement value falls below a threshold amount, indicating that a resource usage attack is in progress. The indicated transmission time is the time used to transmit a payload 22 of the size indicated in header 21. If more (payload) measurements are to be performed, the method returns to the execution payload measurement step 42 to perform the new measurements.

[0048] In step 46, the receiver device 2 releases resources used to receive the payload. Releasing resources may include ending the attempt to decode the payload. Alternatively or additionally, releasing resources may include setting the receiver device 2 to a state where it is ready to receive a new header.

[0049] By releasing resources upon detection of a low-power payload, resource exploitation attacks are stopped and their impact is significantly reduced. This detection does not rely on any checksum calculations, which would require listening and decoding for the entire duration of the indicated payload's transmission, thus failing to mitigate the impact of resource exploitation attacks. Therefore, according to the implementation described herein, energy waste in receiver device 2 is reduced during resource exploitation attacks, and resources and bandwidth are made available for receiving legitimate frames during the time receiver device 2 would otherwise be busy attempting to receive the indicated payload from the attacker's transmitter device 1.

[0050] Figure 5 It is shown Figure 1A schematic diagram of the components of receiver device 2. The processor circuit system 60 may be provided using any combination of one or more of the following: a suitable central processing unit (CPU), graphics processing unit (GPU), multiprocessor, neural processing unit (NPU), microcontroller, digital signal processor (DSP), etc., capable of executing software instructions 67 stored in memory circuit system 64, thus memory circuit system 64 may be a computer program product. Alternatively, the processor circuit system 60 may be implemented using application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), etc. The processor circuit system 60 may be configured to execute the above-described instructions. Figure 4 The method described.

[0051] The memory circuit system 64 may be any combination of random access memory (RAM) and / or read-only memory (ROM). The memory circuit system 64 also includes a non-transitory persistent storage device, which may be any one or a combination of the following: magnetic memory, optical memory, solid-state memory, or even remotely mounted memory.

[0052] A data memory 66 is also provided for reading and / or storing data during the execution of software instructions in the processor circuit system 60. The data memory 66 may be any combination of RAM and / or ROM.

[0053] I / O interface 62 is provided for communication with external and / or internal entities. I / O interface 62 supports short-range wireless communication, such as any communication protocol based on IEEE 802.15.4, including Thread, ZigBee, Wireless Heart, Matter, etc. Alternatively or additionally, I / O interface 62 includes Bluetooth or Bluetooth Low Energy (BLE).

[0054] Other components of receiver device 2 have been omitted to avoid obscuring the concept presented herein.

[0055] Figure 6 An example of a computer program product 90 including a computer-readable device is shown. On this computer-readable device, a computer program 91 can be stored in non-transitory memory. This computer program can cause a processing circuit system to perform methods according to the embodiments described herein. In this example, the computer program product 90 is in the form of a removable solid-state memory such as a Universal Serial Bus (USB) drive. As mentioned above, the computer program product can also be in the memory of a device, such as… Figure 5The computer program product 64 is embodied herein. Although the computer program 91 is schematically shown herein as part of a removable solid-state storage device, the computer program may be stored in any manner suitable for a computer program product, such as another type of removable solid-state storage device or optical disc, such as a CD (compressed disc), DVD (digital versatile disc), or Blu-ray disc.

[0056] Here we now follow a set of implementations listed in Roman numerals from a slightly different perspective.

[0057] I. A method for mitigating resource usage attacks by a transmitter device against a receiver device via a wireless interface, the method being performed by the receiver device, the method comprising:

[0058] Receive a header transmission from a transmitter device. The header forms part of a radio frame. The header includes an indicator of the size of the subsequent transmission of the payload in the radio frame. The receiving includes performing a header measurement, which is a measurement of the signal strength of the received header transmission.

[0059] Perform payload measurement, which is the measurement of the received signal strength when the payload of a radio frame is expected to be received.

[0060] The payload measurement was determined to be below a threshold; and

[0061] Release the resources used to receive the payload.

[0062] II. The method according to embodiment I, wherein the payload measurement is performed repeatedly during the indicated transmission time until the payload measurement value is lower than the header measurement value by a threshold amount.

[0063] III. The method according to Embodiment I or Embodiment II, wherein releasing resources includes ending the attempt to decode the payload.

[0064] IV. The method according to any one of the foregoing embodiments, wherein releasing resources includes setting the receiver device to a state where it is ready to receive a new header.

[0065] V. The method according to any one of the foregoing embodiments, wherein the wireless interface is a short-range wireless interface.

[0066] VI. The method according to embodiment V, wherein the wireless interface conforms to any communication standard according to IEEE 802.15.4.

[0067] VII. The method according to embodiment V, wherein the wireless interface conforms to Bluetooth, Bluetooth Low Energy (BLE), or Z-Wave.

[0068] VIII. The method according to any one of the foregoing embodiments, wherein the threshold is determined relative to the header measurement.

[0069] IX. The method according to any one of embodiments I to VIII, wherein the threshold is a static value.

[0070] X. A receiver device for mitigating attacks on the resource usage of a receiver device by a transmitter device through a wireless interface, the receiver device comprising:

[0071] Processing circuit system; and

[0072] The memory circuit system stores instructions that, when executed by the processing circuit system, cause the receiver device to:

[0073] Receive a header transmission from a transmitter device. The header forms part of a radio frame. The header includes an indicator of the size of the subsequent transmission of the payload in the radio frame. The receiving includes performing a header measurement, which is a measurement of the signal strength of the received header transmission.

[0074] Perform payload measurement, which is the measurement of the received signal strength when the payload of a radio frame is expected to be received.

[0075] The payload measurement was determined to be below a threshold; and

[0076] Release the resources used to receive the payload.

[0077] XI. The receiver device according to embodiment X further includes an instruction, when executed by the processing circuit system, to cause the receiver device to perform the following operation: repeating payload measurements multiple times during an indicated transmission time until the payload measurement value is lower than the header measurement value by a threshold amount.

[0078] XII. The receiver device according to embodiment X or embodiment XI, wherein the instruction to release resources includes an instruction that, when executed by the processing circuitry system, causes the receiver device to terminate the attempt to decode the payload.

[0079] XIII. The receiver device according to any one of embodiments X to XII, wherein the instruction to release resources includes, when executed by the processing circuitry system, an instruction to cause the receiver device to perform the following operation: setting the receiver device to a state in which it is ready to receive a new header.

[0080] XIV. The receiver device according to any one of embodiments X to XIII, wherein the wireless interface is a short-range wireless interface.

[0081] XV. The receiver device according to embodiment XIV, wherein the wireless interface conforms to any communication standard according to the Institute of Electrical and Electronics Engineers IEEE 802.15.4.

[0082] XVI. The receiver device according to embodiment XIV, wherein the wireless interface conforms to Bluetooth or Bluetooth Low Energy (BLE).

[0083] XVII. A receiver device according to any one of embodiments X to XVI, wherein the threshold is determined relative to a header measurement.

[0084] XVIII. A receiver device according to any one of embodiments X to XVII, wherein the threshold is a static value.

[0085] XIX. A computer program for mitigating resource usage attacks by a transmitter device against a receiver device via a wireless interface, the computer program comprising computer program code that, when executed on the receiver device, causes the receiver device to:

[0086] Receive a header transmission from a transmitter device. The header forms part of a radio frame. The header includes an indicator of the size of the subsequent transmission of the payload in the radio frame. The receiving includes performing a header measurement, which is a measurement of the signal strength of the received header transmission.

[0087] Perform payload measurement, which is the measurement of the received signal strength when the payload of a radio frame is expected to be received.

[0088] The payload measurement was determined to be below a threshold; and

[0089] Release the resources used to receive the payload.

[0090] XX. A computer program product comprising a computer program according to embodiment XIX and a computer-readable device, the computer-readable device including a non-transitory memory in which the computer program is stored.

[0091] The foregoing has primarily described various aspects of this disclosure with reference to several embodiments. However, as will be readily understood by those skilled in the art, other embodiments besides those disclosed above are equally possible within the scope of the invention as defined by the appended claims. Therefore, while various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for illustrative purposes and are not intended to be limiting; the true scope is indicated by the appended claims.

Claims

1. A method for mitigating a resource usage attack by a transmitter device (1) on a receiver device (2) over a wireless interface (4), the method being performed by the receiver device (2), the method comprising: receiving (40) a header transmission from a transmitter device (1), the header (21) forming part of a wireless frame (20), the header (21) comprising an indicator of a size of a subsequent transmission of a payload (22) in the wireless frame (20), wherein the receiving comprises performing a header measurement, the header measurement being a measurement of a signal strength of the received header transmission; performing (42) a payload measurement, the payload measurement being a measurement of a received signal strength measurement value when a reception of the payload (22) of the wireless frame (20) is expected, wherein the expectation of when the payload is received is based on the size indicated in the header; determining (44) that the payload measurement value is below a threshold value; and releasing (46) resources for receiving the payload.

2. The method of claim 1, wherein, The performing (42) of the payload measurement is repeated a number of times during the indicated transmission time until the payload measurement value is below the header measurement value by more than a threshold amount.

3. The method of claim 1 or 2, wherein, The releasing (46) of the resources comprises ending an attempt to decode the payload.

4. The method according to any one of the preceding claims, wherein, The releasing (46) of the resources comprises setting the receiver device (2) to a state in which the receiver device (2) is ready to receive a new header.

5. The method according to any one of the preceding claims, wherein, The wireless interface is a short-range wireless interface.

6. The method of claim 5, wherein, The wireless interface (4) is in compliance with any communication standard according to the Institute of Electrical and Electronics Engineers, IEEE 802.15.

4.

7. The method of claim 5, wherein, The wireless interface (4) is in compliance with Bluetooth, Bluetooth Low Energy, BLE, or Z-Wave.

8. The method of any of the preceding claims, wherein, The threshold value is determined relative to the header measurement value.

9. The method of any one of claims 1 to 8, wherein, The threshold value is a static value.

10. A receiver device (2) for mitigating a resource usage attack by a transmitter device (1) over a wireless interface (4), the receiver device (2) comprising: processing circuitry (60); and memory circuitry (64) storing instructions (67) that, when executed by the processing circuitry, cause the receiver device (2) to: receive a header transmission from a transmitter device (1), the header (21) forming part of a wireless frame (20), the header (21) comprising an indicator of a size of a subsequent transmission of a payload (22) in the wireless frame (20), wherein the receiving comprises performing a header measurement, the header measurement being a measurement of a signal strength of the received header transmission; perform a payload measurement, the payload measurement being a measurement of a received signal strength measurement value when a reception of the payload (22) of the wireless frame (20) is expected, wherein the expectation of when the payload is received is based on the size indicated in the header; determine that the payload measurement value is below a threshold value; and release resources for receiving the payload. The performing of the payload measurement is repeated a number of times during the indicated transmission time until the payload measurement value is below the header measurement value by more than a threshold amount.

11. The receiver device (2) according to claim 10, further comprising instructions (67) which, when executed by the processing circuitry, cause the content receiver device (2) to repeat the payload measurement a plurality of times during the indicated transmission time until the payload measurement value is below the header measurement value by more than a threshold amount.

12. The receiver device (2) according to claim 10 or 11, wherein The instructions to release the resources comprise instructions (67) which, when executed by the processing circuitry, cause the content receiver device (2) to end the attempt to decode the payload.

13. The receiver device (2) according to any one of claims 10 to 12, wherein, The instructions to release the resources comprise instructions (67) which, when executed by the processing circuitry, cause the content receiver device (2) to set the receiver device (2) to a state in which the receiver device (2) is ready to receive a new header.

14. The receiver device (2) according to any one of claims 10 to 13, wherein, The wireless interface is a short-range wireless interface.

15. The receiver device (2) according to claim 14, wherein The wireless interface (4) is compliant with any communication standard according to Institute of Electrical and Electronics Engineers, IEEE 802.15.

4.

16. The receiver device (2) according to claim 14, wherein The wireless interface (4) is compliant with Bluetooth or Bluetooth Low Energy, BLE.

17. The receiver device (2) according to any one of claims 10 to 16, wherein The threshold value is determined relative to the header measurement value.

18. The receiver device (2) according to any one of claims 10 to 17, wherein, The threshold value is a static value.

19. A computer program (67, 91) for mitigating a resource usage attack by a transmitter device (1) on a receiver device (2) over a wireless interface (4), the computer program comprising computer program code which, when executed on a receiver device (2), causes the receiver device (2) to: receiving a header transmission from a transmitter device (1), the header (21) forming part of a radio frame (20), the header (21) comprising an indicator of a size of a subsequent transmission of a payload (22) in the radio frame (20), wherein, The receiving comprises performing a header measurement, the header measurement being a measurement of a signal strength of the received header transmission; performing a payload measurement, the payload measurement being a measurement of a signal strength measurement value received when the payload (22) of the wireless frame (20) is expected to be received, wherein the expectation of when the payload is received is based on a size indicated in the header; determine that the payload measurement value is below a threshold value; and release resources for receiving the payload.

20. A computer program product (64, 90) comprising a computer program according to claim 19 and a computer readable means comprising a non-transitory memory having said computer program stored thereby.

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