A 5G-based industrial heterogeneous network edge gateway

Abstract

The present invention provides an industrial heterogeneous network edge gateway based on 5G, and relates to the technical field of industrial heterogeneous networks. The edge gateway is mainly used for cross-domain heterogeneous network communication, that is, the nodes under the local and remote edge gateways communicate with each other. The edge gateway described in the present invention includes a device control management module, a network information management module, a protocol conversion module and a user data control module. The device control management module is responsible for establishing the communication relationship between downstream industrial nodes; the network information management module is responsible for network security risk and network performance parameter collection, and provides data basis for other module decisions; the protocol conversion module is responsible for receiving and extracting industrial message data and memory address mapping, encapsulating and sending messages; the user data control module is responsible for using 5G-based wireless links and Ethernet wired links to perform redundant transmission of IP frames between edge gateways to ensure the reliability and real-time communication between industrial heterogeneous networks.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial heterogeneous gateways, and specifically to a 5G-based industrial heterogeneous network edge gateway. Background Art

[0002] Industrial Internet and Industry 4.0 are important ways for the manufacturing industry to achieve digital transformation. The industrial network is the foundation of the industrial Internet and is generally composed of an industrial field network and an industrial backbone network. The industrial field network includes industrial wireless networks and industrial wired networks, which are used to complete information collection and decision-making control of the production process. The industrial backbone network is an important hub connecting the industrial production site and the Internet. With the continuous development of the next generation of Internet technology, applying 5G to the factory backbone network has become an important development trend.

[0003] In order to meet the diverse needs of industrial production, industrial networks usually adopt heterogeneous networking, which is composed of a variety of industrial wired and wireless networks. Heterogeneity has become a prominent feature of industrial networks. In a heterogeneous environment, device communication between different networks is inseparable from protocol conversion devices. In addition, control data in industrial networks requires highly reliable and low-latency transmission, and protocol conversion efficiency has become a key factor restricting end-to-end cross-network control. In order to achieve efficient protocol conversion, the transmission of heterogeneous industrial data on the Internet has been proposed. However, when data is transmitted on the Internet, it is inevitable to bear delays, packet loss and data leakage caused by network fluctuations and attacks. Therefore, how to safely and stably transmit industrial heterogeneous network data is an important issue in the development of industrial networks. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the shortcomings of the prior art, the present invention provides a 5G-based industrial heterogeneous network edge gateway, which can support efficient intercommunication of cross-domain industrial heterogeneous networks, and use methods such as identity authentication negotiation and data encryption to prevent network attacks, and use 5G and Ethernet as redundant links to ensure stable and efficient cross-domain transmission.

[0006] (II) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: a 5G-based industrial heterogeneous network edge gateway, including a device control management module, a network information management module, a protocol conversion module and a user data control module;

[0008] The equipment control management module is responsible for establishing the communication relationship between downstream industrial nodes; the equipment control management module has the following specific working steps:

[0009] Step 1: The local and remote edge gateways obtain the downstream device list through device connection events;

[0010] Step 2: The local and remote edge gateways establish a secure information channel through IPSec negotiation, and generate and exchange keys for subsequent secure data transmission;

[0011] Step 3: Create a first virtual subnet device and a second virtual subnet device by manual setting or file import, wherein the first virtual subnet device is created by the remote edge gateway and uses the same protocol as the downstream device of the local edge gateway; the second virtual subnet device is created by the local edge gateway and uses the same protocol as the downstream device of the remote edge gateway;

[0012] Step 4: Establish communication instances at the local and remote edge gateways, and notify the protocol conversion modules at both ends of the edge gateways to create corresponding protocol conversion processes and bind them to the communication instances.

[0013] The network information management module is responsible for collecting network security risks and network performance parameters, and provides data basis for decision-making of other modules; the network information management module mainly includes the following sub-functions:

[0014] 1) Management gateway port configuration: Check the frame format and key element values ​​of the data frames uploaded by the downstream devices, and perform forced disconnection actions on the downstream devices whose message error frequency in the edge gateway port exceeds the threshold, and mark this port as abnormal;

[0015] 2) Network performance analysis: Periodically calculate the communication performance parameters between the edge gateway and downstream devices, including throughput, packet loss rate, latency, and periodically calculate the communication quality Q of the 5G link. 5G and the communication quality Q of the Ethernet link ETH , link communication quality Q link The calculation method is:

[0016]

[0017] in, and σ RTT are the mean and variance of the round-trip time of multiple ICMP frames in the link within a continuous period of time, LOSS is the packet loss rate of ICMP frames, and w a_delay 、w v_delay 、w r_loss is the weight of the three indicators, w a_delay represents the throughput, w v_delay represents delay, w r_loss Represents the packet loss rate.

[0018] The protocol conversion module is responsible for receiving and extracting industrial message data and memory address mapping, encapsulating and sending messages; the protocol conversion module creates corresponding protocol conversion processes on the local and remote edge gateways respectively through the communication instance established by the device control management module, and classifies the priority of the messages received from the downstream. Specifically, the data is divided into three priorities from high to low by identifying the interface of the downstream industrial equipment and matching the function code field of the data frame:

[0019] Processing network management control and emergency alarm command frames, process data for industrial automation production monitoring, general data and non-emergency alarm data;

[0020] The data that needs to be converted into a protocol will enter the corresponding protocol conversion process waiting area in sequence according to the data priority. The data that has timed out will temporarily increase its data priority during this process to prevent low-priority data from not being processed.

[0021] The protocol conversion process performs address and value mapping between the industrial protocols that need to be converted and uses the protocol stack of the corresponding virtual subnet device to encapsulate and send data.

[0022] The user data control module is responsible for redundant transmission of IP frames between edge gateways using 5G-based wireless links and Ethernet wired links to ensure the reliability and real-time communication between industrial heterogeneous networks; redundant transmission uses both 5G links and Ethernet links as physical transmission links, and the sender adds the data packet sequence number to the beginning of the IP frame payload, and then uses the key generated by the device control management module to encrypt the data using the AES-256 algorithm when sending;

[0023] The receiver receives data from 5G and Ethernet links in parallel, selects one of the links as the primary link, and only processes data frames received from the primary link. When data frames transmitted by the primary link are lost, out of order, or have a check error, data with the same sequence number is read from the backup link as a replacement.

[0024] Use Ethernet link as the main link for transmission. When Q 5G Both are greater than Q ETH When the 5G link is switched to the main link, the Ethernet link is switched to the backup link.

[0025] (III) Beneficial effects

[0026] The present invention provides a 5G-based industrial heterogeneous network edge gateway, which has the following beneficial effects:

[0027] 1. The present invention uses equipment identity authentication, data encryption and other technologies to protect data communications, which can prevent industrial data from being attacked or stolen when transmitted over an open network.

[0028] 2. The present invention uses a priority marking method to classify data, and then provides storage and computing resources for network resources and industrial heterogeneous network edge gateways. Therefore, when the frequency of data cross-network communication is high, the real-time and reliability of transmission of important production factor information is prioritized, thereby ensuring the stable operation of the industrial system.

[0029] 3. The present invention uses two redundant physical links to transmit cross-network data, and formulates a reasonable backup link compensation mechanism and a primary-backup link switching mechanism. When one of the links has occasional data disorder and packet loss, the backup link data can be immediately called for replacement, which greatly reduces the impact of occasional transmission errors and enhances the reliability of cross-network integration of heterogeneous networks.

[0030] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of a functional module of an industrial heterogeneous network edge gateway based on 5G according to the present invention;

[0032] Figure 2 This is a principle architecture diagram of a 5G-based industrial heterogeneous network edge gateway involved in the present invention;

[0033] Figure 3 A 5G-based industrial heterogeneous network edge gateway and industrial node data transmission path diagram in an embodiment of the present invention;

[0034] Figure 4 The present invention relates to a data mapping area schematic diagram in a 5G-based industrial heterogeneous network edge gateway protocol conversion process. DETAILED DESCRIPTION

[0035] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0036] Figure 1 The present invention shows a schematic diagram of the functional modules of an industrial heterogeneous network edge gateway based on 5G, and the edge gateway architecture includes the following functional modules: device control management module, network information management module, protocol conversion module and user data control module. Among them, the device control management module is responsible for establishing the communication relationship between downstream industrial nodes; the network information management module is responsible for collecting network security risks and network performance parameters, and providing data basis for other module decisions; the protocol conversion module is responsible for receiving and extracting industrial message data and memory address mapping, encapsulating and sending messages; the user data control module is responsible for using 5G-based wireless links and Ethernet wired links to perform redundant transmission of IP frames between edge gateways to ensure the reliability and real-time communication between industrial heterogeneous networks.

[0037] Figure 2 The schematic diagram of the 5G-based industrial heterogeneous network edge gateway of the present invention is shown. The two industrial protocols that need to be converted are controlled and configured through the gateway configuration. The gateway collects the network characteristics and industrial data characteristics of the protocols on both sides, and analyzes the necessary data through the corresponding analysis module to provide it to the security module and gateway configuration, thereby optimizing the gateway protocol conversion and data transmission. In addition, the conversion strategy can also be optimized by analyzing the protocol conversion model.

[0038] Embodiment 1:

[0039] Implement Modbus-TCP master station to control CANopen slave station servo motor.

[0040] Figure 3 The data transmission path diagram between the edge gateway and industrial nodes of heterogeneous networks: In order to establish a communication connection between two nodes in different network areas, indirect conversion is required through the edge gateways in their respective areas. Taking the Modbus-TCP master station host computer controlling the robotic arm of the CANopen slave station protocol as an example, the Modbus-TCP master station node sends data to the edge gateway in this area, and then the gateway packages the data into IP frames and transmits it to the remote edge gateway via Ethernet and 5G. The remote edge gateway parses the data packet and performs protocol conversion, and then uses its virtual subnet node to forward it to the CANopen slave station.

[0041] The specific steps are as follows:

[0042] S1: Configure the gateway's Modbus-TCP and CANopen virtual node communication parameters. The edge gateway directly connected to CANopen is configured as follows:

[0043]

[0044] Edge gateway configuration for direct connection to Modbus-TCP:

[0045]

[0046] S2: Configure Modbus-TCP master and CANopen slave, where Modbus-TCP master is replaced by Modbus master software. CANopen slave is configured using special configuration software. In this example, since the servo motor needs to be controlled, the PDO communication mode with higher real-time performance in the CANopen protocol is used. The PDO parameter configuration is:

[0047] That is, the data that CANopen needs to receive are three parameters: control word, speed and mode.

[0048]

[0049] S3: Use Modbus poll software to configure the parameters of the CANopen slave servo motor:

[0050] First configure the Modbus master parameters:

[0051] Slave ID Function Address Quantity ScanRate(ms) 5 03: Read holding register 750 10 1000

[0052] Then write the parameters you want to configure to the address:

[0053] For this example, you need to write the control word 0x0F00 in the first register, then write the speed value in the second and third registers, and write the speed control mode 0x0300 in the fourth register.

[0054] After performing the above operations, the CANopen slave servo motor under the gateway at the other end can rotate at the set speed.

[0055] After the above operations, the internal working steps of the gateway are:

[0056] S1: The edge gateways on both sides obtain the key used for data transmission between gateways through identity authentication and negotiation mechanism. The communication channel between Modbus-TCP node and CANopen node is opened.

[0057] S2: The Modbus-TCP virtual slave node in the edge gateway receives the write register instruction sent by Modbus poll.

[0058] S3: The edge gateway parses the Modbus-TCP message, first extracting its IP, device ID and other feature information, and at the same time, sampling the traffic of the gateway port running the Modbus-TCP protocol, and sending the above collected data features together into the priority classification model to obtain the priority of the data frame.

[0059] S4: The edge gateway reads the register value information transmitted by the message and stores it in the shared data area. At the same time, the information saved also includes the read and write attributes of the data area, data frame priority, data update method and other information.

[0060] S5: The edge gateway protocol conversion process converts the protocol into CANopen format according to the mapping table, including the conversion of addresses and indexes, and fills in the data mapping area. The specific data mapping area structure is as follows Figure 4 shown.

[0061] S6: The edge gateway on this side sends the packaged data payload to the corresponding port of the remote edge gateway through the Ethernet card and 5G wireless module and marks it with the same data sequence number.

[0062] S7: The sending submodule reads the complete entry in the shared data area, constructs Ethernet data frames and 5G data frames based on the content of the entry, and constructs a sending queue based on the priority information, and then sends it to the receiving gateway through the Ethernet card and 5G module at the same time. The receiving submodule periodically exchanges ICMP frames with the edge gateway at the sending end to calculate the link delay, and selects a link with higher communication quality as the channel for receiving and processing data. In order to ensure that the main link is not switched frequently, a timeout is set, and the switch is only made when the currently selected main link has a higher delay. Finally, the receiving submodule parses the received data frame and sends it to the corresponding virtual subnet node.

[0063] S8: The virtual CANopen master node of the CANopen side gateway packages the data information into a CANopen packet and sends it to the CANopen slave servo motor.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A 5G-based industrial heterogeneous network edge gateway, characterized in that: It includes a device control management module, a network information management module, a protocol conversion module and a user data control module; The equipment control management module is responsible for establishing the communication relationship between downstream industrial nodes; the equipment control management module has the following specific working steps: Step 1: The local and remote edge gateways obtain the downstream device list through device connection events; Step 2: The local and remote edge gateways establish a secure information channel through IPSec negotiation, and generate and exchange keys for subsequent secure data transmission; Step 3: Create a first virtual subnet device and a second virtual subnet device by manual setting or file import, wherein the first virtual subnet device is created by the remote edge gateway and uses the same protocol as the downstream device of the local edge gateway; the second virtual subnet device is created by the local edge gateway and uses the same protocol as the downstream device of the remote edge gateway; Step 4: Establish communication instances at the local and remote edge gateways, and notify the protocol conversion modules at both ends of the edge gateways to create corresponding protocol conversion processes and bind them to the communication instances; The network information management module is responsible for collecting network security risks and network performance parameters, and provides data basis for decision-making of other modules; the network information management module mainly includes the following sub-functions: 1) Management gateway port configuration: Check the frame format and key element values ​​of the data frames uploaded by the downstream devices, and perform forced disconnection actions on the downstream devices whose message error frequency in the edge gateway port exceeds the threshold, and mark this port as abnormal; 2) Network performance analysis: Periodically calculate the communication performance parameters between the edge gateway and downstream devices, including throughput, packet loss rate, latency, and periodically calculate the communication quality Q of the 5G link. 5G and the communication quality Q of the Ethernet link ETH , link communication quality Q link The calculation method is: in, and σ RTT are the mean and variance of the round-trip time of multiple ICMP frames in the link within a continuous period of time, LOSS is the packet loss rate of ICMP frames, and w a_delay 、w v_delay 、w r_loss is the weight of the three indicators, w a_delay represents the throughput, w v_delay represents delay, w r_loss Represents the packet loss rate; The protocol conversion module is responsible for receiving and extracting industrial message data and memory address mapping, encapsulating and sending messages; the protocol conversion module creates corresponding protocol conversion processes on the local and remote edge gateways respectively through the communication instance established by the device control management module, and classifies the priority of the messages received from the downstream. Specifically, the data is divided into three priorities from high to low by identifying the interface of the downstream industrial equipment and matching the function code field of the data frame: Processing network management control and emergency alarm command frames, process data for industrial automation production monitoring, general data and non-emergency alarm data; The data that needs to be converted into a protocol will enter the corresponding protocol conversion process waiting area in sequence according to the data priority. The data that has timed out will temporarily increase its data priority during this process to prevent low-priority data from not being processed. The protocol conversion process performs address and value mapping between industrial protocols that need to be converted and uses the protocol stack of the corresponding virtual subnet device to encapsulate and send data; The user data control module is responsible for redundant transmission of IP frames between edge gateways using 5G-based wireless links and Ethernet wired links to ensure the reliability and real-time communication between industrial heterogeneous networks; redundant transmission uses both 5G links and Ethernet links as physical transmission links, and the sender adds the data packet sequence number to the beginning of the IP frame payload, and then uses the key generated by the device control management module to encrypt the data using the AES-256 algorithm when sending; The receiver receives data from 5G and Ethernet links in parallel, selects one of the links as the primary link, and only processes data frames received from the primary link. When data frames transmitted by the primary link are lost, out of order, or have a check error, data with the same sequence number is read from the backup link as a replacement. Use Ethernet link as the main link for transmission. When Q 5G Both are greater than Q ETH When the 5G link is switched to the main link, the Ethernet link is switched to the backup link.

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