A method for resisting satellite internet of things uplink interference attack

Abstract

The application discloses a method for resisting satellite Internet of Things uplink interference attack, and a satellite Internet of Things system comprises a central gateway, a plurality of service areas and a space segment; the service area comprises a plurality of legal terminal nodes, and the space segment is composed of one or more communication satellites in geostationary or non-geostationary orbits. Each communication satellite provides a single or multiple beams to cover different service areas, the satellite can connect the service areas to the central gateway, and then store collected messages and transmit the messages to the central gateway. The method comprises the following steps: calculating a MAC layer load G, calculating a preamble time, calculating an average data packet arrival number, and calculating a minimum IC step length under a specified detection probability through a Poisson distribution. The application has the advantages that the system performance decline caused by the preamble camouflage attack can be resisted, the preamble deception interference which has a great influence on the system performance is effectively eliminated, and the system stability is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of satellite Internet of Things (IoT) technology, and in particular to a satellite IoT and a method for resisting network spoofing and interference attacks using preamble spoofing receivers. Background Technology

[0002] In recent years, the ever-growing demand for IoT (Internet of Things) in various applications has been a major driving force for research, development, and innovation in many technological fields. The growth rate of the number of connected devices is expected to continue to rise, reaching a connection density of 10 million devices per square kilometer by 2030. The use of satellite networks is considered a natural solution for expanding the IoT service sector in a cost-effective and performance-driven manner.

[0003] Satellite IoT networks provide remote access to a large number of devices while maintaining low access control overhead. In other words, satellite networks can grant users access without pre-allocating capacity for each connection. This approach, also known as random access, reduces the signaling exchange requirements between individual nodes (remote devices) and gateways (on satellites or ground stations).

[0004] The S-MIM protocol, the air interface for S-band mobile interactive multimedia (S-MIM), has emerged as a result of the Satellite Ground Station and System (SES). Its use cases have been commercially deployed to provide networked television and M2M services. In addition to commercial deployments, the S-MIM air interface uses a spread spectrum scheme, which is somewhat resilient to the inherent interference of constant radio uplink channels. However, when the air interface is used externally, especially by using knowledge of the relevant protocols of the physical layer and access layer for interference attacks, its threat may be more serious. Summary of the Invention

[0005] This invention addresses the technical problem that current satellite IoT uplink is susceptible to preamble spoofing interference, leading to system performance degradation. It provides a method to resist satellite IoT uplink interference attacks, thereby enhancing the stability of the ground station receiving system.

[0006] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for resisting uplink interference attacks in satellite IoT systems, the method being implemented based on a satellite IoT system, includes the following steps:

[0008] S101: Calculate the MAC layer load G; the value of the MAC load G is used to identify systems that are significantly affected by disturbances. The larger the value of G, the greater the disturbance to the system.

[0009] Specifically: Let the number of 10-millisecond frames contained in the uplink burst structure after the preamble be the data burst length DBL, and the strength be... The time corresponding to the data packets generated by the random Poisson process is used The MAC load is obtained as follows:

[0010]

[0011] Where: G is the MAC layer load, R c Here, SF is the symbol rate, DBL is the spreading factor, and DBL is the data burst length.

[0012] S102: Calculate the preamble time; continuously search for a valid preamble, and perform the data detection required before the interference cancellation IC after the preamble is found; specifically: the preamble specified by TFI in E-SSA is 12 bytes, the number is fixed and equal to 96, and the preamble time is:

[0013]

[0014] S103: Calculate the average number of data packets arriving; to limit the complexity of interference cancellation, the receiver limits the step size of interference cancellation, which depends on the expected number of data packets in the observation window; specifically: within a duration equal to one preamble time The formula for calculating the average number of data packets arriving during the observation window is:

[0015]

[0016] S104: Calculate the minimum IC step size for a specified detection probability using a Poisson distribution;

[0017] The Poisson distribution is calculated as follows:

[0018]

[0019] Where k is the number of preamble symbols in the observation window, P k This represents the probability of the k-th data packet arriving;

[0020] Let the acceptable probability of missed detection be... The detection probability is greater than The minimum IC step size required for all block preambles is calculated as follows:

[0021]

[0022] The satellite Internet of Things system includes: a central gateway, multiple service areas, and a space segment;

[0023] The service area includes multiple legitimate terminal nodes, including IoT devices and jamming devices; the space segment consists of one or more communication satellites in geostationary or non-geostationary orbits; each communication satellite provides one or more beams to cover different service areas, acting as multiple service cells; a two-way communication link between the satellite and each service area is used to broadcast public messages to all terminal nodes and collect messages from terminal nodes using a random access direct channel; each satellite can operate transparently to connect its service area to a central gateway, using an onboard communication protocol to transmit collected messages to the central gateway.

[0024] Compared with the prior art, the advantages of the present invention are as follows:

[0025] Based on the ETSI S-MIM standard, the model assumes that attackers launch interference attacks via the ESS-A access protocol. It introduces a random Poisson process to describe the arrival strength and load of random data packets in the uplink and calculates the actual interference cancellation step size required to detect the preamble of all data packets within the observation window. This enables the receiving system to resist performance degradation caused by preamble spoofing attacks, effectively eliminating preamble deception interference that significantly impacts system performance and greatly improving system stability. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the system architecture of the satellite Internet of Things according to an embodiment of the present invention;

[0027] Figure 2 This is a flowchart of the main operation loop of the E-SSA protocol according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the sequential detection loop of the E-SSA protocol in an embodiment of the present invention;

[0029] Figure 4 This is a flowchart of a method for resisting uplink interference attacks in satellite IoT according to an embodiment of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples.

[0031] like Figure 1 As shown, the main subsystem architecture of the satellite IoT, upon which the method for resisting uplink interference attacks is based, includes:

[0032] The system comprises a gateway and multiple service areas, including a large number of legitimate IoT devices and potentially some jammer devices. The space segment can consist of one or more communication satellites in geostationary or non-geostationary orbits. Each satellite provides one or more beams to cover different geographic service areas, acting as multiple service areas. It is assumed that a two-way communication link between the satellite and each service area broadcasts public messages to all end nodes and collects messages from the nodes themselves using a random access direct channel. Each satellite can operate transparently to connect its service area to the central ground gateway, or it can implement an onboard communication protocol (e.g., as a re-emergence payload), subsequently storing the collected messages and transmitting them to the central gateway.

[0033] like Figure 2 As shown, the proposed method for resisting uplink interference attacks in satellite IoT is based on the E-SSA access protocol main loop flow, which explains in detail the specific process of receiver data acquisition and interference elimination:

[0034] The received signal is described by the following equation:

[0035] (1)

[0036] In equation (1), Let be the uplink channel gain (terminal to satellite) corresponding to the i-th IoT terminal. For the corresponding delay, The signal sent by the terminal. This is satellite receiver noise. Each transmitted signal from an IoT node contains a preamble (universal across all nodes) and a data field (node-specific), which can be represented as follows:

[0037] (2)

[0038] therefore, Represents the preceding time span, while This represents the time span of the data block. To synchronize the preamble for a specific user, the received signal is transmitted through a pulse response... The correlation filter has the following output:

[0039] (3)

[0040] Continuous sampling to estimate time delay As long as detection is performed, each data packet corresponding to a specific delay is reconstructed and subtracted from the received signal through an IC process.

[0041] like Figure 3 As shown, on the timeline, the receiver operation is characterized by a continuous search for a valid preamble within the scanning window, followed by the detection of the data required by the IC. In summary, the receiver operation is described as follows:

[0042] (1) In the scanning window, the preamble is continuously scanned and attempted to be detected.

[0043] (2) If a preamble is detected, the receiver waits to receive the entire data portion to check its validity (by using CRC).

[0044] (3) If a valid data packet is found, its contribution is removed from the received signal and the preamble scan is restarted. This means that the scan window is fully processed after the full duration of a data packet (preamble and data field).

[0045] like Figure 4 As shown, the interference cancellation step size selection process includes:

[0046] Step 1: Calculate MAC layer load

[0047] The step size of the IC to be executed at the receiver depends on the number of preambles within the observation window. This, in turn, depends on the MAC layer load G and the TFI (Transmission Format Indicator) under consideration. The latter depends on... (Symbol rate), SF (spreading factor), and DBL (data burst length), i.e., the number of 10-millisecond frames contained in the uplink burst structure after the preamble. Assuming the strength is... The data packets and time generated by the random Poisson process are used The data packets are represented by k, where k represents the k-th data packet. The MAC load can be obtained as follows:

[0048] (4)

[0049] Step 2: Calculate the lead time

[0050] Since the TFI specification in ESS-A defines a preamble of 12 bytes, which is fixed and equal to 96, the preamble time is:

[0051] (5)

[0052] Step 3: Calculate the average number of data packets arriving.

[0053] The duration is equal to one preamble time. During the observation window, the average number of data packets arriving was:

[0054] (6)

[0055] Step 4: Calculate the minimum IC step size for the specified detection probability using the Poisson distribution.

[0056] Despite average A valid indication of the required number of IC steps is provided, but more refined analysis is needed to evaluate the actual number of IC steps required to detect the preamble of all packets within the observation window, depending on the Poisson distribution.

[0057] (7)

[0058] Where k is the number of preamble symbols in the observation window.

[0059] Let the acceptable probability of missed detection be... The detection probability is greater than The minimum IC step size required for all block preambles is

[0060] (8)

[0061] The methods of the present invention described above can be implemented in hardware, firmware, or as software or computer code that can be stored in a recording medium (such as a CD-ROM, RAM, floppy disk, hard disk, or magneto-optical disk), or as computer code originally stored on a remote recording medium or a non-transitory machine-readable medium and subsequently stored on a local recording medium, downloaded via a network. Thus, the methods described herein can be processed by software stored on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It is understood that the computer, processor, microprocessor controller, or programmable hardware includes storage components (e.g., RAM, ROM, flash memory, etc.) capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the processing methods described herein. Furthermore, when a general-purpose computer accesses the code used to implement the processing shown herein, the execution of the code transforms the general-purpose computer into a dedicated computer for performing the processing shown herein.

[0062] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the implementation methods of the present invention, and should be understood that the scope of protection of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of the present invention.

Claims

1. A method for resisting uplink interference attacks in satellite Internet of Things (IoT), characterized in that: The method for resisting uplink interference attacks from satellite IoT is based on a satellite IoT system and includes the following steps: S101: Calculate the MAC layer load G; the value of the MAC load G is used to identify systems that are significantly affected by disturbances. The larger the value of G, the greater the disturbance to the system. Specifically: Let the number of 10-millisecond frames contained in the uplink burst structure after the preamble be the data burst length DBL, and the strength be... The time corresponding to the data packets generated by the random Poisson process is used The MAC load is obtained as follows: ； Where: G is the MAC layer load, R c Here, SF is the symbol rate, DBL is the spreading factor, and DBL is the data burst length. S102: Calculate the preamble time; continuously search for a valid preamble, and perform the data detection required before the interference cancellation IC after the preamble is found; specifically: the preamble specified by TFI in E-SSA is 12 bytes, the number is fixed and equal to 96, and the preamble time is: ； S103: Calculate the average number of data packets arriving; to limit the complexity of interference cancellation, the receiver limits the step size of interference cancellation, which depends on the expected number of data packets in the observation window; specifically: within a duration equal to one preamble time The formula for calculating the average number of data packets arriving during the observation window is: ； S104: Calculate the minimum IC step size for a specified detection probability using a Poisson distribution; The Poisson distribution is calculated as follows: ； Where k is the number of preamble symbols in the observation window, P k This represents the probability of the k-th data packet arriving; Let the acceptable probability of missed detection be... The detection probability is greater than The minimum IC step size required for all block preambles is calculated as follows: ； The satellite Internet of Things system includes: a central gateway, multiple service areas, and a space segment; The service area includes multiple legitimate terminal nodes, including IoT devices and jamming devices; the space segment consists of one or more communication satellites in geostationary or non-geostationary orbits; each communication satellite provides one or more beams to cover different service areas, serving as multiple service cells; a two-way communication link between the satellite and each service area is used to broadcast public messages to all terminal nodes and collect messages from terminal nodes using a random access direct channel; each satellite can operate transparently to connect its service area to the central gateway and transmit the collected messages to the central gateway using an airborne communication protocol.

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