Multi-mode dynamic switching vehicle-mounted bus network communication system and method

Abstract

According to the multi-mode dynamic switching vehicle-mounted bus network communication system and method provided by the invention, through dynamic switching among different communication modes, the security of the vehicle-mounted bus network is improved, and the risks of being decoded and attacked are reduced. The system comprises an initial communication configuration module, a dynamic channel updating module, an anti-attack mode communication module, a mode switching control module, a mode switching monitoring module and a mode switching optimization module. According to the invention, network attacks can be effectively prevented, and automobile network security is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive network security, and particularly to a multi-mode dynamic switching in-vehicle bus network communication system and method. Background Art

[0002] Traditional in-vehicle bus network protocols (such as CAN bus) did not fully consider network security issues during design, making them vulnerable to attacks. Attackers can obtain the network signal list or directly read the signals on the bus, decipher the network signal definition, and then forge or interfere with the signals, affecting the normal operation of the vehicle. Existing solutions usually rely on hardware encryption, which increases the complexity of circuit design and material costs, and is not applicable to software upgrades of existing products. Summary of the Invention

[0003] The purpose of the present invention is to provide a multi-mode dynamic switching in-vehicle bus network communication system and method, which improves the security of the in-vehicle bus network by dynamically switching between different communication modes and reduces the risk of being deciphered and attacked.

[0004] To achieve the above object, the present invention provides the following technical solutions: A multi-mode dynamic switching in-vehicle bus network communication system includes an initial communication configuration module for establishing factory mode communication when triggered by a vehicle ignition signal and generating an initial signal information table; A dynamic channel update module for periodically updating the signal information table through ring message interaction. The signal information table includes message ID, signal layout, and byte order, and emergency communication signals are embedded during the update process; An attack response module for triggering an anti-attack mode when detecting network anomalies, accelerating the update of the signal information table, and injecting interference messages; It includes a mode switching control module for dynamically switching between different communication modes according to vehicle status, network load, and attack events; the mode switching control module includes switching from the factory mode to the self-update channel mode, switching from the self-update channel mode to the anti-attack mode, and switching from the anti-attack mode to the self-update channel mode.

[0005] As a preferred technical solution of the present invention, the mode switching control module includes: a seamless switching sub-module for preloading the communication parameters of the target mode into a dual buffer before mode switching and maintaining communication continuity through message priority scheduling.

[0006] As a preferred technical solution of the present invention, it includes a mode switching monitoring module for real-time recording of the bus load rate and attack characteristic data during mode switching.

[0007] As a preferred technical solution of the present invention, it includes a mode switching optimization module for dynamically adjusting the trigger threshold of the anti-attack mode according to the attack feature data.

[0008] A multi-mode dynamic switching vehicle bus network communication method includes the following steps: When the vehicle ignition signal is triggered, a network management node is selected, and the signal information table is dynamically updated based on the ring message interaction. The signal information table includes the message ID, signal layout, and byte order; The communication parameters are dynamically adjusted through multi-mode switching of the factory mode, self-update channel mode, and anti-attack mode; In the self-update channel mode, the signal information table is updated periodically; when a network attack is detected, it switches to the anti-attack mode, enables the emergency communication signal table, injects interference signals, and accelerates the update cycle; After the attack is eliminated, it returns to the self-update process through the security timeout mechanism.

[0009] As a preferred technical solution of the multi-mode dynamic switching vehicle bus network communication method of the present invention, the signal information table update step includes: The network management node sends a signal information reconstruction flag token message to the bus; Each node forms a ring according to the original ID order, and the network management node monitors the preset ring formation time. Newly added nodes after the timeout are ignored; The management node issues a new ID order through the ring message, and each node updates the ID number to be used next; When the network management node recognizes the end of the ring formation, it sets a start update flag in the ring message; Each node generates the transmission signal information including the normal communication signal table and the emergency communication signal table according to the update rules issued by the management node; the emergency communication signal table is generated through the following rules: a. Disperse the original signals to different messages and add random interference signals at the idle positions of the messages; b. Dynamically adjust the message ID and DLC length, and group the signals and bind them to the same message; c. The management node controls that the number of newly added interference messages does not exceed the bus load threshold; Each node parses the received ring message, updates the local received signal information table, and marks the completion flag; After the management node confirms that all nodes have the completion flag, it sends an update completion instruction to terminate the ring message interaction.

[0010] As a preferred technical solution of the multi-mode dynamic switching vehicle bus network communication method of the present invention, when a network attack is detected, the following steps are executed: 1) When a node detects abnormal network communication, it sends an alarm message to the bus, which can be received by other nodes and the network management node; 2) The network management node sends an abnormal update token message to notify each node to enter the group ring and confirm the node's online status; 3) Each node starts to send group ring messages. Similar to the update process, after the group ring time ends, if a new node is received, the node is ignored; 4) The network management node recognizes the end of the group ring and sends an abnormal update instruction. Each node switches to send messages according to a preset emergency communication signal table, and the emergency communication signal table includes interference signals and encryption communication parameters.

[0011] Compared with the prior art, the beneficial effects of the present invention are: 1. The vehicle-mounted bus network status is changed in multiple modes such as the factory mode, self-update channel mode, and anti-attack mode respectively. During use, it is in the self-update channel mode to protect the vehicle-mounted bus network information and reduce the risks of deciphering and attacking; 2. The factory mode is used for communication within the initial specified time range of network communication establishment, establishing an information basis for transitioning to the self-update channel mode. The self-update channel mode is used in most communication times, making the network signal definition in a floating and constantly changing state, reducing the risks of being deciphered and attacked; 3. The anti-attack mode is a communication mode entered when an abnormality on the network is recognized, which speeds up the update of the floating channel, introduces cover information, and warns of network risks, etc., to increase the difficulty of being deciphered. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is the system framework diagram of the present invention; Figure 2 is a partial update flow chart of the signal information table of the present invention; Figure 3 is another partial update flow chart of the signal information table of the present invention; Figure 4 is the flow chart of attack detection and mode switching of the present invention; Figure 5 is the schematic diagram of the message structure in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments and drawings. However, the following embodiments are only the preferred embodiments of the present invention, not all of them. Based on the embodiments in the implementation manners, other embodiments obtained by those skilled in the art without creative efforts all fall within the protection scope of the present invention.

[0014] The specific embodiments of the present invention will be described below in conjunction with the drawings.

[0015] Such as Figures 1 to 5A multi-mode dynamic switching vehicle bus network communication system and method as shown.

[0016] Among them, the system includes an initial communication configuration module with a factory mode, which is used to establish factory mode communication when triggered by a vehicle ignition signal, generate an initial signal information table. In the factory configuration stage, once the communication link is established, the system will, based on the real-time monitoring of the network status, intelligently set the self-updating channel mode adopted for subsequent communication by the network management node. This mode involves multiple parameters such as the specific form of communication, the start and end duration of communication, and the transition method. After the factory communication is established, the system will automatically switch from the factory mode to the self-updating channel mode to adapt to the changing network environment.

[0017] A dynamic channel update module with a self-updating channel mode, which is used to periodically update the signal information table through ring message interaction. The signal information table includes message ID, signal layout, and byte order, and emergency communication signals are embedded during the update process. In the self-updating channel mode, the system will, according to the dynamic instructions of the network management node, adjust the channel form of data communication in real time. This includes but is not limited to modifying the message header format, signal layout, signal byte order, and the duration of this communication to ensure the efficiency and security of data transmission. If an attack behavior is identified during this process, the system will quickly switch to the anti-attack mode and take necessary security measures, such as changing the communication frequency, encryption algorithm, etc. The timeout time is set for this mode switching process. After the timeout ends, if there are no new attack signs, the system will resume to the factory mode.

[0018] An attack response module with an anti-attack mode, which is used to trigger the anti-attack mode when detecting network anomalies, accelerate the update of the signal information table, and inject interference messages; It includes a mode switching control module, which is used to dynamically switch between different communication modes according to the vehicle state, network load, and attack events; the mode switching control module includes the switching from the factory mode to the self-updating channel mode, the switching from the self-updating channel mode to the anti-attack mode, and the switching from the anti-attack mode to the self-updating channel mode.

[0019] The mode switching control module includes: a seamless switching sub-module, which is used to preload the communication parameters of the target mode into the double buffer area before mode switching and maintain communication continuity through message priority scheduling. It includes a mode switching monitoring module, which is used to record the bus load rate and attack characteristic data during mode switching in real time. It includes a mode switching optimization module, which is used to dynamically adjust the trigger threshold of the anti-attack mode according to the attack characteristic data. In this embodiment, the seamless switching sub-module, the mode switching control module, the mode switching monitoring module, the mode switching optimization module, the dynamic channel update module, the attack response module, and the initial communication signal module are all software modules. This is prior art and not the focus of this application, and there is no improvement in programming, so no specific elaboration is made.

[0020] The mode switching control module in this embodiment: Considering various factors such as vehicle driving state, network environment, and safety requirements, it carefully designs the mode switching strategy to ensure that the communication process is both efficient and secure. The strategy includes the regular switching from the factory mode to the self-update channel mode, and the emergency switching to the anti-attack mode when an attack is detected; Mode switching control module: During the switching process, seamless connection technology is adopted to greatly reduce the possibility of communication interruption and data loss, and enhance the coherence and reliability of communication. The switching from the factory mode to the self-update channel mode and then to the anti-attack mode ensures a smooth transition, and at the same time dynamically adjusts communication parameters to optimize performance. Mode switching monitoring: Real-time monitoring of the entire process of mode switching, once an abnormal situation is detected, immediately initiate emergency response measures to ensure the continuous and stable operation of the vehicle communication network; Mode switching optimization module: Through the collection and analysis of communication data, continuously optimize and upgrade the mode switching strategy to further improve the overall performance and safety level of the in-vehicle bus network. In particular, the communication data in the anti-attack mode will provide important references for strategy optimization and ensure the effectiveness of the timeout recovery mechanism.

[0021] A multi-mode dynamic switching in-vehicle bus network communication method includes the following steps: When the vehicle ignition signal is triggered, select the network management node, and complete the dynamic update of the signal information table based on the ring message interaction. The signal information table includes message ID, signal layout, and byte order; Through the multi-mode switching of the factory mode, self-update channel mode, and anti-attack mode, dynamically adjust the communication parameters; Periodically update the signal information table in the self-update channel mode; when a network attack is detected, switch to the anti-attack mode, enable the emergency communication signal table, inject interference signals and accelerate the update cycle. In this embodiment, the interference signals are filled with pseudo-random numbers generated by the management node into the idle bytes of the message, and do not cover the functional signal fields. The pseudo-random seed is derived from the current IGN cycle number.

[0022] After the attack is eliminated, return to the self-update process through the security timeout mechanism.

[0023] The signal information table update steps include: The network management node sends a signal information reconstruction flag token message (Rebuild flag) to the bus; After each node receives the token message, group the rings in sequence according to the originally defined ID; The network management node continuously monitors for 1S or 3 times the ring message cycle. If no new node joins, the ring grouping ends; If the ring grouping timeouts and a new node joins, ignore the node; The network management node will order the new ID into the ring message, which is received by each node, and each node updates the ID number to be used next time; The network management node recognizes the end of the ring formation and sets a start update flag (Updating flag) in the ring message; Each node generates transmission signal information including a normal communication signal table and an emergency communication signal table according to the update rules issued by the management node; The nodes on this bus receive the ring messages sent by others, analyze the signal information therein, parse the received signal information therein, and update the local received signal information table; After each node has sent its own transmission signal information, it will set a completion flag (Complete flag) in the ring message. When the network management node monitors that each node in the ring (the nodes that passed the verification during the ring formation stage) has set the completion flag of its respective ring message; the network management node sends the current update completion flag (Updated flag), and each node stops sending its respective ring message.

[0024] In this embodiment, the management node is dynamically elected or predefined and specified by a certain node in the in - vehicle bus network, and is responsible for coordinating the signal table update and mode switching; other nodes are ordinary nodes, responding to the instructions of the management node and performing communication parameter updates; the ring message consists of a base address and an ID number. Each node needs to update the new ID of the node interacting with itself, and find the interacting node through the new ID next time (the base address of the ring message is a configurable parameter); the network management node can be elected or specified during network design; the transmission of the ring message can be encrypted or not, and encryption can be used as a stronger protection according to the protection strength.

[0025] When a network attack is detected, the following steps are executed: 1) When a node detects abnormal network communication (such as: 1. Message flooding; 2. Sending less than twice the normal period; 3. Sending continuous AliveCount messages non - monotonically increasing, etc.), it will send an alarm message to the bus, which can be received by other nodes and the network management node; 2) The network management node sends an abnormal update token message (abnormal update token (ExceptionAlive flag)) to notify each node to enter the ring formation and confirm the node's online status; 3) Each node starts to send ring formation messages. Similar to the update process, after the ring formation time ends, if a new node is received, it will be ignored; 4) The network management node recognizes the end of the group ring and sends an exception update instruction (ExceptionUpdate flag). Each node switches to send messages according to a preset emergency communication signal table. The emergency communication signal table includes interference signals and encryption communication parameters. The encryption communication parameters are a dynamically generated message check code and a temporary communication key based on a time stamp. The interference signal is randomly filled bytes inserted into the idle positions of the message.

[0026] The application message in this embodiment refers to a conventional message that transmits vehicle function signals (such as vehicle speed, steering command) in the in - vehicle bus network, and its signal definition is dynamically controlled by a signal information table; the ring message: refers to a special management message for signal information table synchronization, including a base address, a node ID, a signal information segment, and a status flag, and does not participate in vehicle function control.

[0027] The system of the present invention has multiple modes such as a factory mode, a self - updating channel mode, and an anti - attack mode to change the state of the in - vehicle bus network. During use, it is in the self - updating channel mode to protect the in - vehicle bus network information and reduce the risks of deciphering and attacking. The self - updating channel mode avoids the weakness that the traditional fixed network signal list defined at the factory is easily deciphered, making it difficult for attackers to reverse - obtain the network signal definition. Because in the self - updating channel mode, the signal definition transmitted within a period of time will be replaced with a new one, so that attackers cannot obtain enough messages for reverse analysis.

[0028] Among them: The factory mode is used for communication within the initial specified time range of network communication establishment, establishing an information basis for transitioning to the self - updating channel mode. The self - updating channel mode is used for most communication times, making the network signal definition in a floating and constantly changing state, reducing the risks of being deciphered and attacked. Among them: The anti - attack mode is a communication mode entered when an abnormality on the network is recognized, which speeds up the update of the floating channel, introduces cover information, and warns of network risks, etc., to increase the difficulty of being deciphered.

[0029] Among them: By switching between factory - mode communication, self - updating channel - mode communication, and anti - attack - mode communication, the security of the in - vehicle bus network is improved. These functions are mainly implemented by software, without the need for hardware or a dedicated chip, and the material cost will not increase.

[0030] The multi - mode dynamic switching in - vehicle bus network communication method of the present invention can be applied to the communication protection of underlying layers such as in - vehicle LIN, CAN, Ethernet... Dynamically change the channel and the definition of the communication data position in the software, reducing the risk of fixed data bit information being cracked.

[0031] The update strategy for sending signal information (emergency communication signal table) in the present invention is as follows: (1) The signals can be dispersed into different messages; (2)The number of messages is variable, and interference messages are added (1-2 frames of messages are added under actual load conditions. Adding more will increase the bus load, and the management node will issue which ID nodes can add); (3)Random interference signals are added at the idle positions of the messages; (4)The position and byte order of the signals are variable, and the length is fixed; (5)Group signals need to be assigned to the same message; (6)The CAN ID is variable; (7)The DLC length is variable.

[0032] The update strategy of the signal information table dynamically adjusts specific parameters such as signal distribution, message structure, and interference rules in a certain mode (such as the self-updating channel mode or the anti-attack mode) to ensure the unpredictability of signal definitions. The signal table update strategy supports mode switching: in the self-updating channel mode, the dynamic changes of the signal table (such as variable CAN ID and floating signal positions) are the core implementation means of the mode switching strategy. In the anti-attack mode, the rapid update of the signal table and the interference mechanism are the key defense measures of the mode switching strategy. The signal table update strategy is the underlying execution rule that defines "how" to achieve dynamic protection in a specific mode.

[0033] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present invention and do not limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A multi-mode dynamic switching vehicle bus network communication system, characterized by: It includes an initial communication configuration module for establishing factory mode communication when the vehicle ignition signal is triggered and generating an initial signal information table; A dynamic channel update module, used to periodically update the signal information table through ring message interaction, wherein the signal information table includes a message ID, signal layout and byte order, and an emergency communication signal is embedded during the update process; An attack response module is used to trigger an anti-attack mode when a network anomaly is detected, accelerate the update of the signal information table, and inject interference messages; It also includes a mode switching control module for dynamically switching between different communication modes according to vehicle status, network load and attack events; the mode switching control module includes switching from factory mode to self-update channel mode, switching from self-update channel mode to anti-attack mode, and switching from anti-attack mode to self-update channel mode.

2. The multi-mode dynamic switching vehicle bus network communication system according to claim 1 is characterized in that: The mode switching control module includes: a seamless switching submodule, which is used to preload the communication parameters of the target mode into the double buffer area before the mode switching, and maintain the communication continuity through the message priority scheduling.

3. The multi-mode dynamic switching vehicle bus network communication system according to claim 1 is characterized in that: It includes a mode switching monitoring module for recording the bus load rate and attack feature data during mode switching in real time.

4. The multi-mode dynamic switching vehicle bus network communication system according to claim 1 is characterized in that: It includes a mode switching optimization module for dynamically adjusting the triggering threshold of the anti-attack mode according to the attack feature data.

5. A multi-mode dynamic switching vehicle bus network communication method, applied to the multi-mode dynamic switching vehicle bus network communication system as claimed in any one of claims 1 to 4, characterized in that: The following steps are involved: When the vehicle ignition signal is triggered, a network management node is selected to dynamically update the signal information table based on the ring message interaction, wherein the signal information table includes the message ID, signal layout, and byte order; Dynamically adjust communication parameters through multi-mode switching between factory mode, self-update channel mode, and anti-attack mode; In the self-update channel mode, the signal information table is updated periodically; when a network attack is detected, it switches to the anti-attack mode, activates the emergency communication signal table, injects interference signals and accelerates the update cycle; After the attack is eliminated, the system will return to the self-update process through the security timeout mechanism.

6. The multi-mode dynamic switching vehicle bus network communication method according to claim 5 is characterized in that: The signal information table updating step comprises: The network management node sends a signal information reconstruction token message to the bus; Each node forms a ring according to the original ID sequence. The network management node monitors the preset ring formation time. New nodes added after the timeout are ignored. The management node sends a new ID sequence through a ring message, and each node updates the ID number to be used next time; The network management node recognizes that the ring group has ended and sets the start update flag in the ring message; Each node generates the transmission signal information including the normal communication signal table and the emergency communication signal table according to the update rules issued by the management node. The emergency communication signal table is generated according to the following rules: a. The original signal is dispersed into different messages, and a random interference signal is added to the idle position of the message; b. The message ID and DLC length are dynamically adjusted, and the group signal is bound to the same message; c. The management node controls the number of newly added interference messages not to exceed the bus load threshold; Each node parses the received ring message, updates the local received signal information table, and marks the completion flag; After the management node confirms that all nodes have completed the flag, it sends an update completion instruction and terminates the ring message interaction.

7. The multi-mode dynamic switching vehicle bus network communication method according to claim 5 is characterized in that: When a network attack is detected, the following steps are performed: 1) When a node detects network communication anomalies, it will send an alarm message to the bus, which can be received by other nodes and network management nodes; 2) The network management node sends an exception update token message to notify each node to enter the group ring and confirm that the node is online; 3) Each node starts to send ring formation messages, the same as the update process. After the ring formation time ends, if a new node is received, it will be ignored; 4) The network management node recognizes that the ring group is finished and sends an abnormal update instruction, and each node switches to send messages according to a preset emergency communication signal table, wherein the emergency communication signal table includes interference signals and encrypted communication parameters.

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