A large-scale constellation network semi-physical simulation test system and method

Abstract

The application provides a large-scale constellation network semi-physical simulation test system and method, which comprises a constellation simulator, a satellite-borne router, ground inspection equipment and a protocol conversion network bridge, a Mininet simulation platform is deployed, dynamic topology adjustment, OSPF dynamic routing protocol and multi-scene test functions are supported; a user can observe network topology changes, routing update time and key performance indicators in real time. The application realizes a semi-physical simulation architecture through unified IP subnet interconnection and the same routing protocol, a time-space synchronization engine ensures that virtual and real node routing tables are atomically effective at a specified time, combined with a protocol consistency sandbox, implicit faults caused by inconsistent behaviors of hardware and software protocol stacks are solved, and the application also supports the access of multiple real nodes in a large-scale network environment, end-to-end data transmission test, security policy verification and protocol compatibility analysis; the application provides an efficient, flexible and reliable solution for the design, verification and optimization of satellite networks, and has a wide application prospect.

Description

Technical Field

[0001] This invention relates to the field of measurement and testing technology, specifically to a large-scale constellation network hardware-in-the-loop simulation testing system and method. Background Technology

[0002] With the rapid development of satellite communication technology, large-scale constellation networks have gradually become a research hotspot. Large-scale constellation networks consist of hundreds or even thousands of satellites, possessing complex topologies and dynamic characteristics. To verify the performance of constellation networks, simulation technology has become an important research tool. However, traditional pure software simulation systems (such as Mininet), while capable of simulating network topology and protocol behavior, have shortcomings in terms of realism and dynamism. For example, Mininet may face performance bottlenecks when handling large-scale networks, especially in dynamic topology updates and protocol conversions.

[0003] Hardware-in-the-loop (HIL) simulation technology combines a virtual network environment with real physical devices to provide simulation results that more closely resemble actual operating environments. This technology has been widely used in ad hoc and complex network research, but in the field of satellite networks, especially large-scale constellation networks, HIL simulation system research is still in its early stages. Most existing HIL simulation systems focus on testing terrestrial networks or small satellite networks, and lack sufficient support for the complex topologies and dynamic changes of large-scale constellation networks.

[0004] Furthermore, the CCSDS protocol commonly used in satellite networks differs from the Ethernet protocol used in terrestrial networks, making protocol conversion a critical issue in hardware-in-the-loop (HIL) simulation systems. Currently, while some research attempts to implement protocol conversion through software, these methods still require improvement in terms of real-time performance and efficiency.

[0005] Therefore, there is an urgent need to develop a hardware-in-the-loop simulation testing system that can support large-scale constellation networks, while simultaneously addressing the issues of protocol conversion and dynamic topology updates. Summary of the Invention

[0006] This invention addresses the problems of existing simulation systems in large-scale constellation network research, such as the inability to effectively combine virtual simulation with real physical devices, inconsistencies in the behavior of virtual nodes and equivalent satellite nodes, low protocol conversion efficiency, and insufficient dynamic topology update capabilities. It provides a hardware-in-the-loop (HIL) simulation testing system and method for large-scale constellation networks. This invention integrates a virtual network environment, a real onboard router, ground testing equipment, and a protocol conversion bridge into a HIL. It achieves high-precision dynamic simulation of large-scale constellation networks and efficient testing and verification of network performance, providing a reliable testing platform that more closely approximates the actual operating environment for satellite network research and development.

[0007] This invention provides a large-scale constellation network hardware-in-the-loop simulation test system, comprising a ground-based testing device, a satellite-borne router, a protocol conversion bridge, and a constellation simulator connected in sequence.

[0008] The ground testing equipment is a ground-based support device for the satellite-borne router. It sends control commands to the satellite-borne router, monitors and records the parameters of the satellite-borne router, collects the operating data of the satellite-borne router in real time, and displays it through a graphical interface.

[0009] The onboard router is an equivalent satellite node, which can perform integrated routing and forwarding of intra-satellite, inter-satellite, and satellite-to-ground data. It supports dynamic routing protocols and automatically updates the routing table when the topology changes. The number of equivalent satellite nodes is at least one.

[0010] The constellation simulator includes the Mininet simulation platform, which simulates satellite network topology and network protocols. The constellation simulator can dynamically adjust the network topology, create, modify, and delete virtual nodes and links in the constellation network. The constellation simulator can perform dynamic routing networking with equivalent satellite nodes and test the convergence time of dynamic routing when the topology changes. It provides an extensible Python API for network creation and experimentation, and tests the end-to-end data transmission latency, network bandwidth, and security policies.

[0011] The protocol conversion bridge connects the constellation simulator and the onboard router to perform the conversion between Ethernet frame protocol and CCSDS frame protocol. The protocol conversion bridge is equipped with a time-space synchronization engine.

[0012] The spatiotemporal synchronization engine is used to compensate for the time flow rate difference between the equivalent satellite nodes and the constellation simulator, calculate the adaptive delay, and broadcast the topology snapshot with the effective timestamp to the equivalent satellite nodes through the out-of-band channel, triggering the equivalent satellite nodes to pre-compute the routing table; the spatiotemporal synchronization engine injects adaptive delay into the Mininet simulation platform, and after the delay ends, the new path is enabled across the entire network;

[0013] All virtual nodes and all equivalent satellite nodes in the constellation simulator are configured on the same IP subnet and run the same network routing protocol, with no awareness or communication between the nodes.

[0014] The large-scale constellation network hardware-in-the-loop simulation test system described in this invention, as a preferred embodiment, includes a satellite router comprising a power module, a platform management module, and a routing module, which can realize the network functions of real satellite nodes and interact with the simulation platform;

[0015] The constellation simulator includes a set of parameterized topologies, supports the OSPF dynamic routing protocol, and has a graphical user interface. Users can build and manage virtual networks through scripts. The constellation simulator can perform multi-scenario tests and can connect to at least two real nodes for network testing.

[0016] The protocol conversion bridge includes a protocol conversion module, a data encapsulation module, a flow control module, a spatiotemporal synchronization engine, and a protocol consistency sandbox;

[0017] The protocol conversion module identifies and converts different network protocols, performs conversion between Ethernet frame protocols and CCSDS frame protocols, and supports interoperability of heterogeneous networks.

[0018] The data encapsulation module encapsulates the data to adapt it to the transmission format of the target network;

[0019] The flow control module is used to avoid network congestion and data loss;

[0020] The space-time synchronization engine calculates the adaptive delay, delay = k × T_real, where k is a dynamic margin coefficient, which can be changed by setting, and k is usually set between 1.2 and 1.5; T_real is the OSPF convergence time.

[0021] The protocol consistency sandbox detects whether the MTU of the Ethernet frames sent by the virtual node exceeds the carrying capacity of the real node. If it exceeds the limit, it automatically corrects the virtual node configuration, forces the virtual node to fragment or injects ICMP to fragment it.

[0022] In the large-scale constellation network hardware-in-the-loop simulation test system described in this invention, k is preferably in the range of 1.2 to 1.5.

[0023] Multi-scenario testing includes satellite constellation networking scenarios, network performance testing scenarios, security policy testing scenarios, protocol compatibility testing scenarios, and dynamic topology update scenarios;

[0024] The satellite constellation networking scenario simulates the networking process of a large-scale satellite constellation, verifying the dynamic changes in network topology and the adaptability of routing protocols;

[0025] Network performance testing scenarios test the end-to-end performance metrics of the network and evaluate the network's performance under different load conditions. End-to-end performance metrics include latency, bandwidth, and packet loss rate.

[0026] The security policy test scenario simulates security threats and verifies the security policies and protection mechanisms of the satellite network. Security threats include network attacks, unauthorized node access, and unauthorized data transmission.

[0027] The protocol compatibility test scenario verifies the MTU / QoS behavior alignment between CCSDS and the Ethernet protocol stack through a protocol consistency sandbox, and verifies the interoperability of heterogeneous networks.

[0028] The dynamic topology update scenario simulates link interruption and recovery caused by satellite motion, testing the network's dynamic adaptability and routing convergence time. The spatiotemporal synchronization engine performs atomic switching of routing tables between virtual nodes and equivalent satellite nodes, with a convergence time difference of ≤5ms.

[0029] This invention provides a hardware-in-the-loop simulation testing method for large-scale constellation networks, comprising the following steps:

[0030] S1. Connect the constellation simulator, protocol conversion bridge, satellite router and ground detection equipment in sequence. The satellite router is an equivalent satellite node.

[0031] S2. Create a virtual topology for the constellation network on the constellation network simulator with the Mininet simulation platform deployed. The virtual topology includes satellite nodes, links, and ground stations. Configure the network topology according to the design parameters of the satellite constellation to obtain virtual nodes. The network topology includes orbital altitude, number of satellites, and link bandwidth.

[0032] S3. Use the Mininet simulation platform to perform dynamic topology adjustments, simulate satellite motion trajectories and link status changes, and update the network topology in real time through Python scripts so that the simulation environment reflects the actual operating status of the satellite constellation.

[0033] S4. Configure all virtual nodes and equivalent satellite nodes in the same IP subnet, set the link port IP address, and enable virtual nodes and equivalent satellite nodes to communicate directly with each other based on the IP layer.

[0034] S5. Use ground inspection equipment to configure the parameters of the satellite router, monitor the OSPF convergence time T_real of the satellite router, and ensure that the satellite router is in normal operation. The parameters of the satellite router include node information, orbit information, and link information.

[0035] S6. Configure port information and protocol conversion rules in the protocol conversion bridge to ensure that the ports connected to the onboard router and the protocol conversion bridge correspond one-to-one with the ports connected to the constellation simulator, enabling seamless conversion between Ethernet frames and CCSDS frames; enable the protocol consistency sandbox in the protocol conversion bridge to detect and calibrate the differences in MTU, QoS marking, and routing calculation parameters between virtual nodes and equivalent satellite nodes in real time.

[0036] S7. Verify the routing and networking capabilities between virtual nodes and equivalent satellite nodes: Enable the OSPF dynamic routing protocol of the constellation simulator and the on-board router, record the start time T0, perform dynamic routing and networking between virtual nodes and equivalent satellite nodes, and the networking completion time is T1. Then, the time required for all satellites to complete networking is T = T1 - T0.

[0037] The S8 protocol conversion bridge's spatiotemporal synchronization engine broadcasts a snapshot of the topology, including a specified effective timestamp T+delay, to the equivalent satellite node. Here, delay is the adaptive delay, calculated as k × T_real, where k is the dynamic margin coefficient. The Mininet simulation platform injects the adaptive delay and updates the topology. The equivalent satellite node atomically activates its pre-computed routing table at time T+delay. The routing convergence time difference Δt between the virtual node and the equivalent satellite node is recorded through the onboard router's graphical interface to evaluate dynamic adaptability.

[0038] S9. Select any two nodes in the network, align the traffic parameters through the protocol consistency sandbox, and test the network's end-to-end latency, bandwidth, and packet loss rate to evaluate the network's performance under different load conditions.

[0039] S10. Simulate security threats between equivalent satellite nodes and virtual nodes to verify the security policies and protection mechanisms of the satellite network. Security threats include network attacks, unauthorized node access, and unauthorized data transmission.

[0040] S11. Connect at least two equivalent satellite nodes, configure them according to the methods in steps S6 to S10, and test the transmission delay, network bandwidth, and effectiveness of security policies for end-to-end data between any two nodes in the network. A semi-physical simulation test method for a large-scale constellation network is thus completed.

[0041] The hardware-in-the-loop simulation test method for large-scale constellation networks described in this invention, as a preferred embodiment, includes the following steps in step S6: The conversion process from Ethernet frames to CCSDS frames:

[0042] SA1. Receive Ethernet frames and parse IP data packets: The protocol conversion module of the protocol conversion bridge receives Ethernet frames from the constellation simulator, parses the Ethernet frames, and extracts IP data packets. The parsing process includes identifying the Ethernet frame header information and extracting the IP data packet content. The Ethernet frame header information includes the source MAC address, destination MAC address, and protocol type.

[0043] SA2. Encapsulate IP packets into CCSDS frames: The extracted IP packets are encapsulated according to the CCSDS protocol standard. CCSDS frame header information is added to the header of the IP packets to obtain the encapsulated CCSDS frames. The encapsulated CCSDS frames are then checked and encoded. The CCSDS frame header information includes the synchronization word, frame length, sequence number, and data field.

[0044] SA3. Sending CCSDS frames to the onboard router: The encapsulated CCSDS frames are sent to the onboard router through the physical link. During the transmission process, the flow control module of the protocol conversion bridge monitors the link status. The onboard router receives the encapsulated CCSDS frames and performs decapsulation processing to recover the original IP data packets.

[0045] The hardware-in-the-loop simulation test method for large-scale constellation networks described in this invention, as a preferred embodiment, includes the following steps in step S6: The conversion process from CCSDS frames to Ethernet frames:

[0046] SB1, Receiving CCSDS Frames and Parsing IP Data Packets: The protocol conversion module of the protocol conversion bridge receives CCSDS frames from the onboard router, parses the CCSDS frames, extracts the IP data packets, and performs integrity verification. The parsing process includes identifying the CCSDS frame header information and extracting the IP data packet content. The CCSDS frame header information includes the synchronization word, frame length, and sequence number.

[0047] SB2. Encapsulate IP packets into Ethernet frames: According to the Ethernet protocol standard, the extracted IP packets are encapsulated to obtain encapsulated Ethernet frames, and then checked and encoded. The encapsulation process includes adding Ethernet frame header information to the IP packet header. The Ethernet frame header information includes the source MAC address, destination MAC address, and protocol type.

[0048] SB3, Sending Encapsulated Ethernet Frames to the Terrestrial Network: The encapsulated Ethernet frames are sent to the constellation simulator via the physical link. During the transmission process, the flow control module of the protocol conversion bridge monitors the link status. The constellation simulator receives the encapsulated Ethernet frames and performs decapsulation processing to recover the original IP data packets.

[0049] The hardware-in-the-loop simulation testing method for large-scale constellation networks described in this invention, as a preferred method, includes the following detailed testing of S9:

[0050] S91. Configure the specified network topology on the Mininet simulation platform, including satellite nodes, ground stations, and links; set the link delay, bandwidth, and packet loss rate to simulate the transmission conditions of a real satellite network.

[0051] S92. Use a network traffic generation tool to generate different types of traffic between any two nodes in the network. Record network performance indicators, including end-to-end latency, throughput, and packet loss rate, through the real-time monitoring function of the Mininet simulation platform. The protocol consistency sandbox detects whether the MTU of the Ethernet frame sent by the virtual node exceeds the carrying capacity of the real node. If it exceeds the limit, automatically correct the virtual node configuration and force the virtual node to fragment or inject ICMP.

[0052] S93. Analyze test data, evaluate network performance under different load conditions, display the changing trends of performance indicators through a graphical user interface, and optimize network configuration.

[0053] The hardware-in-the-loop simulation testing method for large-scale constellation networks described in this invention, in a preferred embodiment, includes the following steps in step S8:

[0054] S81. All nodes in the network run the OSPF dynamic routing protocol. The link interruption or recovery caused by satellite motion is simulated on the Mininet simulation platform. At the same time, the spatiotemporal synchronization engine automatically intercepts the event and generates an event ID.

[0055] S82. Collect the historical value T_real of the OSPF convergence time of real nodes through ground inspection equipment, and calculate the adaptive time delay = k * T_real using the spatiotemporal synchronization engine.

[0056] S83, the spatiotemporal synchronization engine broadcasts a topology snapshot to real nodes out of band, including a specified effective timestamp T+delay;

[0057] S84. After receiving the snapshot, the equivalent satellite node freezes the forwarding plane and suspends data plane forwarding. It calculates a new routing table based on the snapshot and waits for the effective time to switch the routing table.

[0058] S85, the space-time synchronization engine injects adaptive time delay into virtual nodes, and the virtual nodes update the new topology after the adaptive time delay ends;

[0059] S86. Observe the update process of the routing table of the nodes in the network. From the link interruption to the recovery, the graphical interface displays the comparison chart of the routing convergence time axis of the virtual node and the equivalent satellite node and the atomicity status indicator of the topology switch in real time. The atomicity status indicator includes synchronization success and synchronization failure.

[0060] The hardware-in-the-loop simulation testing method for large-scale constellation networks described in this invention, in a preferred embodiment, includes the following steps in step S10:

[0061] S101. Configure security policies in the simulation environment, including node access authentication rules and firewall rules;

[0062] S102. Use security testing tools to simulate network attacks and monitor the network security status in real time through a graphical user interface. Network attacks include any one or more of the following: DDoS attacks, data tampering, and unauthorized access.

[0063] S103. Assess the network's ability to defend against attacks. Through log analysis and performance indicator monitoring, determine whether the security policy can prevent attacks and protect the normal operation of the network.

[0064] The hardware-in-the-loop simulation testing method for large-scale constellation networks described in this invention, in a preferred embodiment, includes the following steps in step S11:

[0065] S111. Construct a virtual topology of a large-scale constellation network on the Mininet simulation platform and configure the network topology to simulate the operating environment of an actual satellite constellation.

[0066] S112. Connect at least two onboard routers as equivalent satellite nodes to the simulation system, and use a protocol conversion bridge to perform protocol conversion and data interaction between the equivalent satellite nodes and the virtual network.

[0067] S113. Configure each equivalent satellite node, including IP address allocation, routing protocol settings and security policy configuration, so that all nodes can communicate normally and participate in network testing;

[0068] S114. Use a network traffic generation tool to generate different types of data traffic between any two nodes in the network, and test the end-to-end data transmission latency, network bandwidth, and the effectiveness of security policies between any two nodes in the network. The protocol consistency sandbox unifies the traffic parameter MTU.

[0069] This invention combines a virtual simulation platform with real physical devices to achieve high-precision dynamic simulation and performance testing of satellite networks. The system includes a constellation simulator, onboard routers, ground-based testing equipment, and protocol conversion bridges. It deploys the Mininet simulation platform, supporting dynamic topology adjustments, OSPF dynamic routing protocol, and multi-scenario testing. Through a graphical user interface, users can observe network topology changes, route update times, and key performance indicators in real time. This invention also supports accessing multiple real nodes in large-scale network environments for end-to-end data transmission testing, security policy verification, and protocol compatibility analysis. With detailed testing procedures and optimization suggestions, this invention provides an efficient, flexible, and reliable solution for the design, verification, and optimization of satellite networks, with broad application prospects.

[0070] The present invention has the following advantages:

[0071] (1) This invention achieves a semi-physical simulation architecture by unifying IP subnet interconnection and using the same routing protocol, combining the virtual network environment (constellation simulator) with real physical devices (spaceborne routers), thus eliminating the mapping and layering bottleneck of traditional semi-physical simulation. This architecture can not only simulate the complex topology and dynamic changes of large-scale constellation networks, but also ensure that the simulation results are consistent with the behavior of actual spaceborne devices through hardware-in-the-loop design, thereby improving the realism and reliability of the simulation.

[0072] (2) Dynamic topology updates enable atomic switching. The spatiotemporal synchronization engine ensures that the routing tables of virtual nodes and equivalent satellite nodes take effect atomically at a specified time, overcoming the routing black hole or loop problem caused by the instantaneous update of virtual nodes and the second-level convergence of real nodes in traditional simulations. Combined with the protocol consistency sandbox, it solves the hidden faults caused by the inconsistency between hardware and software protocol stack behavior, and improves the reliability of simulation.

[0073] (3) Hardware-in-the-loop (HIL) simulation technology can significantly reduce the reliance on physical prototypes, replacing 90% of satellite hardware prototypes with lightweight virtualization (Mininet), saving R&D time and costs. By verifying network protocols and topologies in a simulation environment, potential problems can be identified early, reducing development risks and shortening the network verification cycle. Attached Figure Description

[0074] Figure 1 A schematic diagram of a hardware-in-the-loop simulation test system architecture for a large-scale constellation network.

[0075] Figure 2 A schematic diagram of a hardware-in-the-loop simulation test system architecture for a large-scale constellation network.

[0076] Figure 3 A flowchart of a hardware-in-the-loop simulation test method for large-scale constellation networks;

[0077] Figure 4 This is a schematic diagram of dynamic topology updates for a semi-physical simulation test method for large-scale constellation networks. Detailed Implementation

[0078] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Example 1

[0079] like Figure 1 , 2As shown, a large-scale constellation network hardware-in-the-loop simulation test system is presented. This system achieves deep integration of the virtual network environment and real physical devices by constructing a hardware-in-the-loop simulation architecture consisting of a constellation simulator, onboard routers, ground-based detection equipment, and a protocol conversion bridge. All virtual and real nodes are configured on the same IP subnet and run the same network routing protocol, enabling seamless inter-node communication. A spatiotemporal synchronization engine is deployed in the protocol conversion bridge, broadcasting topology snapshots to real nodes via out-of-band control channels and injecting adaptive delays into the Mininet to ensure atomic switching of routing tables between virtual and real nodes during dynamic topology updates, reducing convergence time differences. Through this architecture, this invention not only improves the realism and dynamism of the simulation but also supports comprehensive testing and verification of network protocols, topology structures, and routing algorithms, providing an efficient and reliable testing platform for the research and development of large-scale constellation networks.

[0080] The large-scale constellation network hardware-in-the-loop simulation test system is configured with constellation simulators, protocol conversion bridges, onboard routers, and ground testing equipment connected in pairs. The constellation simulator is equipped with the Mininet simulation platform to simulate the topology and network protocols of the satellite network. The onboard router, acting as an equivalent satellite node, supports integrated routing and forwarding of intra-satellite, inter-satellite, and satellite-to-ground data. The ground testing equipment, connected to the onboard router, serves as a ground-based companion device for the router. The protocol conversion bridge (hereinafter referred to as the bridge) connects the constellation simulator and the onboard router, enabling the conversion between standard Ethernet frame protocols and CCSDS frame protocols, and deploys a spatiotemporal synchronization engine within the protocol conversion bridge.

[0081] The constellation simulator deploys the Mininet simulation platform, supports arbitrary custom constellation topologies, and includes a set of basic parametric topologies. It can dynamically adjust network topologies, supporting the creation, modification, and deletion of virtual nodes and links in large-scale constellation networks to simulate satellite motion and link status changes. It supports the OSPF dynamic routing protocol, enabling dynamic routing networking between virtual and real nodes and testing the convergence time of dynamic routing during topology changes. It provides an extensible Python API for network creation and experimentation, allowing users to flexibly build and manage virtual networks through scripts. It features a graphical user interface for real-time observation of network topology changes and route update time prompts. It also supports multi-scenario testing, allowing access to multiple real nodes in large-scale network environments for network testing, and can test performance metrics such as end-to-end data transmission latency, network bandwidth, and security policies.

[0082] The satellite-borne router supports integrated routing and forwarding of intra-satellite, inter-satellite, and satellite-to-ground data, realizing the network functions of real satellite nodes. It adopts a modular design, including a power module, a platform management module, and a routing module, to realize the network functions of real satellite nodes and interact with the simulation platform to adapt to different testing requirements. It supports dynamic routing protocols (such as OSPF) and can automatically update the routing table when the topology changes.

[0083] The power module provides stable power support; the platform management module handles network control and management commands; and the routing module implements routing algorithms, enables fast inter-satellite data transmission, and facilitates efficient intra-satellite data forwarding.

[0084] Ground-based monitoring equipment is used to send control commands to the satellite-borne router, monitor and record key parameters of the satellite-borne router, collect the router's operating data in real time, and display it to the user through a graphical interface.

[0085] The bridge includes a protocol conversion module, a data encapsulation module, a spatiotemporal synchronization engine, and a protocol consistency sandbox;

[0086] The protocol conversion module identifies and converts different network protocols, enabling seamless conversion between standard Ethernet frame protocols and CCSDS frame protocols, and supporting interoperability of heterogeneous networks.

[0087] The data encapsulation module encapsulates the data to adapt to the transmission format of the target network, ensuring the integrity of data transmission;

[0088] The flow control module prevents network congestion and data loss, ensuring network stability;

[0089] The spatiotemporal synchronization engine solves the problem of time flow difference between the "virtual world" and the "physical world" in semi-physical simulation. It calculates the adaptive delay delay = k × T_real, where k is a dynamic margin coefficient that can be changed by setting. k is usually set between 1.2 and 1.5. It broadcasts a topology snapshot with an effective timestamp to the real nodes through out-of-band channels, triggers the real nodes to pre-compute the routing table, and injects the adaptive delay into Mininet. After the delay ends, the new path is enabled across the entire network.

[0090] The protocol consistency sandbox resolves the inconsistency in protocol processing between virtual nodes (Linux kernel) and real nodes (embedded operating system) caused by differences in operating systems during hardware-in-the-loop simulation. It detects whether the MTU of Ethernet frames sent by virtual nodes exceeds the carrying capacity of real nodes; if so, it automatically corrects the virtual node configuration, forces virtual node fragmentation, or injects ICMPFragmentation Needed.

[0091] The large-scale constellation network hardware-in-the-loop simulation testing system supports multi-scenario testing, the construction and switching of various test scenarios, and the ability to edit and configure different test scenarios, including but not limited to the following:

[0092] Satellite constellation networking scenario: Simulate the networking process of a large-scale satellite constellation to verify the dynamic changes in network topology and the adaptability of routing protocols;

[0093] Network performance testing scenarios: Test network performance metrics such as end-to-end latency, bandwidth, and packet loss rate to evaluate network performance under different load conditions;

[0094] Security policy testing scenarios: Simulate security threats such as network attacks, unauthorized node access, and unauthorized data transmission to verify the security policies and protection mechanisms of the satellite network;

[0095] Protocol compatibility testing scenario: Verify the MTU / QoS behavior alignment between CCSDS and the Ethernet protocol stack through a protocol consistency sandbox to ensure interoperability of heterogeneous networks;

[0096] Dynamic topology update scenario: Simulate link interruption and recovery caused by satellite motion to test the network's dynamic adaptability and routing convergence time. Atomic switching of virtual and physical node routing tables is achieved through a spatiotemporal synchronization engine, with a convergence time difference of ≤5ms.

[0097] Example 2

[0098] like Figure 3 , 4 As shown, a semi-physical simulation testing method for large-scale constellation networks includes the following steps:

[0099] S1: Connect the constellation simulator, protocol conversion bridge, satellite router and ground test equipment to determine if all connections are normal. If yes, proceed to step S2; otherwise, reconnect the devices.

[0100] S2: On the constellation network simulator with the Mininet simulation platform deployed, create a virtual topology for a large-scale constellation network, including satellite nodes, links, and ground stations. Configure the network topology according to the satellite constellation's design parameters, such as orbital altitude, number of satellites, and link bandwidth.

[0101] S3: Utilizing Mininet's dynamic topology adjustment capabilities, simulate satellite trajectory and link status changes. Network topology is updated in real-time via Python scripts to ensure the simulation environment accurately reflects the actual operational status of the satellite constellation.

[0102] S4: Configure all virtual nodes and real nodes in the same IP subnet, set the link port IP address, and ensure that virtual nodes can communicate directly with each other based on the IP layer.

[0103] S5: Use ground inspection equipment to configure the parameters of the satellite router, including node information, orbit information, link information, etc., and monitor its OSPF convergence time T_real to ensure that it is in normal operating condition.

[0104] S6: Configure port information and protocol conversion rules in the bridge to ensure a one-to-one correspondence between the ports connecting the satellite router and the bridge, and between the ports connecting the bridge and the constellation simulator, enabling seamless conversion between Ethernet frames and CCSDS frames. Enable the protocol consistency sandbox to detect and calibrate differences in MTU (Maximum Transmission Unit), QoS tags, and routing calculation parameters between virtual and physical nodes in real time.

[0105] The conversion process from Ethernet frames to CCSDS frames in S6 includes the following steps:

[0106] SA1: Receives Ethernet frames and parses IP packets. The bridge's protocol conversion module receives Ethernet frames from the constellation simulator. It parses the Ethernet frames to extract the IP packets. The parsing process includes identifying Ethernet frame header information (such as source MAC address, destination MAC address, protocol type, etc.) and extracting the IP packet content.

[0107] SA2: Encapsulates IP packets into CCSDS frames. According to the CCSDS protocol standard, the extracted IP packets are encapsulated. CCSDS frame header information, including synchronization words, frame length, sequence number, and data fields, is added to the IP packet header. The encapsulated CCSDS frames are then checked and encoded to ensure data integrity and reliability.

[0108] SA3: Sends CCSDS frames to the onboard router. The encapsulated CCSDS frames are sent to the onboard router via the physical link. During transmission, the bridge's flow control module monitors the link status to ensure smooth data transmission and prevent network congestion and data loss. Upon receiving the CCSDS frames, the onboard router decapsulates them to recover the original IP data packets and continues with subsequent routing and forwarding.

[0109] The conversion process from CCSDS frames to Ethernet frames in S6 includes the following steps:

[0110] SB1: Receives CCSDS frames and parses IP packets. The bridge's protocol conversion module receives CCSDS frames from the onboard router. It parses the CCSDS frames to extract the IP packets. The parsing process includes identifying the CCSDS frame header information (such as synchronization words, frame length, sequence number, etc.) and extracting the IP packet content. The parsed IP packets undergo integrity verification to ensure that the data has not been corrupted during transmission.

[0111] SB2: Encapsulates IP packets into Ethernet frames. According to the Ethernet protocol standard, the extracted IP packets are encapsulated. Ethernet frame header information, including source MAC address, destination MAC address, and protocol type, is added to the IP packet header. The encapsulated Ethernet frame is then checked and encoded to ensure data integrity and reliability.

[0112] SB3: Send Ethernet frames to the terrestrial network. The encapsulated Ethernet frames are sent to the constellation simulator via the physical link. During transmission, the bridge's flow control module monitors the link status to ensure smooth data transmission and prevent network congestion and data loss. Upon receiving the Ethernet frames, the constellation simulator decapsulates them to recover the original IP packets and continues with subsequent processing.

[0113] S7: Enable OSPF dynamic routing protocol on the constellation simulator and satellite router, record the start time as T0, realize dynamic routing network between virtual nodes and real nodes, record the time when the network is completed as T1, calculate the time required for all satellites to complete the network T=T1-T0, and verify the routing network capability between virtual nodes and real nodes.

[0114] S8: The spatiotemporal synchronization engine broadcasts a topology snapshot to real nodes, including a specified effective timestamp T+delay, where delay = k × T_real; Mininet injects the delay and updates the topology, and real nodes atomically enable the pre-computed routing table at time T+delay; the convergence time difference Δt between virtual and real nodes is recorded through a graphical interface to evaluate dynamic adaptability.

[0115] The detailed test for step S8 is as follows:

[0116] S81: When all nodes in the network are running the OSPF dynamic routing protocol, the Mininet platform simulates link interruption or recovery caused by satellite motion, and the spatiotemporal synchronization engine automatically intercepts the event and generates an event ID.

[0117] S82: Collect historical values ​​of OSPF convergence time T_real of real nodes through ground inspection equipment, and calculate adaptive time delay = k * T_real using the spatiotemporal synchronization engine.

[0118] S83: The spatiotemporal synchronization engine broadcasts a topology snapshot to real nodes out of band, including a specified effective timestamp T+delay.

[0119] S84: After receiving the snapshot, the real node freezes the forwarding plane, suspends data plane forwarding, calculates a new routing table based on the snapshot, and waits for the routing table to switch when it takes effect.

[0120] S85: The time-space engine injects time delays into virtual nodes, and the virtual nodes update the new topology after the time delay ends.

[0121] S86: Observe the update process of the routing table of nodes in the network. From the time the link is interrupted to the time it is restored, the interface will display a comparison chart of the convergence timeline of virtual and physical node routes and the atomicity status indicator of topology switching ("synchronization successful or failed") in real time.

[0122] S9: Select any two nodes in the network, ensure traffic parameters are aligned through a protocol consistency sandbox, test the network's end-to-end latency, bandwidth, packet loss rate and other performance indicators, and evaluate the network's performance under different load conditions.

[0123] The detailed test for step S9 is as follows:

[0124] S91: Configure a specific network topology on the Mininet platform, including satellite nodes, ground stations, and links. Set the link latency, bandwidth, and packet loss rate to simulate the transmission conditions of a real satellite network.

[0125] S92: Use network traffic generation tools (such as iperf, netperf) to generate different types of traffic (such as TCP, UDP) between any two nodes in the network. Through Mininet's real-time monitoring function, record network performance metrics, including end-to-end latency, throughput, and packet loss rate. The protocol consistency sandbox detects whether the MTU of Ethernet frames sent by virtual nodes exceeds the carrying capacity of real nodes. If it does, automatically correct the virtual node configuration, forcing virtual node fragmentation or injecting ICMPFragmentation Needed.

[0126] S93: Analyzes test data and evaluates network performance under different load conditions. It displays performance metric trends through a graphical user interface, allowing for optimization of network configuration to improve performance.

[0127] S10: Simulate security threats such as network attacks, unauthorized node access, and unauthorized data transmission between physical and virtual nodes to verify the security strategies and protection mechanisms of the satellite network.

[0128] The detailed test for step S10 is as follows:

[0129] S101: Configure security policies in the simulation environment, including node access authentication rules and firewall rules. Simulate the security environment of a satellite network to ensure the security of data transmission.

[0130] S102: Simulate network attacks using security testing tools (such as nmap and Wireshark), including DDoS attacks, data tampering, and unauthorized access. Monitor the network's security status in real time through a graphical user interface.

[0131] S103: Verify the effectiveness of the security policy and assess the network's ability to protect itself from attacks. Through log analysis and performance metric monitoring, confirm whether the security policy can effectively prevent attacks and protect the normal operation of the network.

[0132] S11: In a large-scale network environment, connect multiple real nodes to test the end-to-end data transmission latency, network bandwidth, and the effectiveness of security policies between any two nodes in the network.

[0133] The detailed test for step S11 is as follows:

[0134] S111: Construct a virtual topology for a large-scale constellation network on the Mininet simulation platform, including satellite nodes, links, and ground stations. Configure the network topology to simulate the operating environment of a real satellite constellation.

[0135] S112: Connect multiple onboard routers as real nodes to the simulation system. A bridge is used to achieve protocol conversion and data exchange between the real nodes and the virtual network.

[0136] S113: Configure each real node, including IP address allocation, routing protocol settings, and security policy configuration. Ensure all nodes can communicate normally and participate in network testing.

[0137] S114: Using a network traffic generation tool, different types of data traffic are generated between any two nodes in the network. The end-to-end data transmission latency, network bandwidth, and security policy effectiveness between any two nodes in the network are tested. The protocol consistency sandbox ensures the uniformity of the traffic parameter MTU. A semi-physical simulation test method for large-scale constellation networks is completed.

[0138] Example 3

[0139] like Figure 1 , 3 As shown in Figure 4, a semi-physical simulation testing method for large-scale constellation networks is described. The simulation testing system is connected to one physical node and includes the following steps:

[0140] S1: Connects the constellation simulator, protocol conversion bridge, satellite router, and ground inspection equipment, such as... Figure 1 As shown.

[0141] S2: On the constellation network simulator with the Mininet simulation platform deployed, create a virtual topology for a constellation network containing 100 low-Earth orbit (LEO) satellites. The satellites are evenly distributed across 10 orbital planes, with 10 satellites per plane. The satellite orbital altitude is 1000 km. Each satellite has four inter-satellite links: two within the same orbit and two outside the same orbit. Assign the satellites numbers 1-100. The links between nodes simulate inter-satellite links, with each link having a bandwidth of 1 Gbps. Configure the network topology according to the satellite constellation's design parameters, including orbital altitude, number of satellites, and link bandwidth.

[0142] S3: Utilizing Mininet's dynamic topology adjustment capabilities, simulate satellite trajectory and link status changes. Network topology is updated in real-time via Python scripts to ensure the simulation environment accurately reflects the actual operational status of the satellite constellation.

[0143] S4: Connect Node 1 as a physical node to the virtual platform. Nodes 2 and 10 are connected to the same orbital satellites as Node 1, while Nodes 11 and 91 are connected to satellites in different orbits. All four inter-satellite link ports of the physical node's onboard router are connected to a protocol conversion bridge. Configure all virtual nodes and physical nodes on the same IP subnet, and assign different IP addresses to the four inter-satellite links of the onboard router to ensure direct communication between virtual nodes based on the IP layer.

[0144] S5: Use ground inspection equipment to configure the parameters of the satellite router, node number 1, run OSPF routing protocol, etc., and monitor its OSPF convergence time T_real to ensure that it is in normal operating condition.

[0145] S6: Configure the protocol conversion bridge, setting port information and protocol conversion rules within the bridge to ensure a one-to-one correspondence between the ports connecting the onboard router and the bridge, and between the bridge and the constellation simulator, achieving seamless conversion between CCSDS frames and Ethernet frames. Enable the protocol consistency sandbox to detect and calibrate differences in MTU (Maximum Transmission Unit), QoS tags, and routing calculation parameters between virtual and physical nodes in real time.

[0146] S7: Run the constellation simulator and the OSPF dynamic routing protocol on the satellite router, record the start time as T0, realize the dynamic routing network between virtual nodes and real nodes, record the time when the network is completed as T1, calculate the time required for 100 satellites to complete the network T=T1-T0, and verify the routing network capability between virtual nodes and real nodes.

[0147] S8: Simulate link interruption and recovery caused by satellite motion on a constellation simulator. Observe network topology changes and route update time prompts in real time through a graphical user interface. At a certain time T1 during network operation, the link is interrupted, and the route convergence time is tested. When the route update is completed, record the time T2. The route convergence time caused by the link interruption is T = T2 - T1. Then, the link is restored, and the time T3 is recorded. The route convergence time is tested again, and when the route update is completed, record the time T4. The route convergence time caused by the link restoration is T = T4 - T3.

[0148] S9: Use the iperf tool to generate data traffic between virtual and real nodes to simulate data transmission in a satellite network. Record the network throughput as 1Gbps with a packet loss rate of 0%.

[0149] S10: Use the ping tool to generate data traffic between virtual and real nodes to simulate data transmission in a satellite network. Record the network transmission latency.

[0150] S11: Configure security policies for physical and virtual nodes, including node access authentication rules and firewall rules, to simulate the security environment of a satellite network. Use nmap to simulate a DDoS attack and monitor the network security status in real time using Wireshark. Test results show that the firewall successfully blocked the DDoS attack, the network operated normally, and the effectiveness of the security policies was verified.

[0151] Example 4

[0152] like Figure 2 , 3 As shown in Figure 4, a semi-physical simulation testing method for large-scale constellation networks is described. The simulation testing system is connected to three physical nodes and includes the following steps:

[0153] S1: In the environment deployed in Implementation Example 1, connect 3 real nodes, namely nodes 1, 12, and 23, as follows: Figure 4 As shown. The co-orbiting satellites connected to physical node 1 are virtual nodes 2 and 10; the non-co-orbiting satellites connected to physical node 1 are virtual nodes 11 and 91. The co-orbiting satellites connected to physical node 12 are virtual nodes 11 and 13; the non-co-orbiting satellites connected to physical node 12 are virtual nodes 2 and 22. The co-orbiting satellites connected to physical node 23 are virtual nodes 22 and 24; the non-co-orbiting satellites connected to physical node 23 are virtual nodes 13 and 33.

[0154] S2: Connect all four inter-satellite link ports of the three physical node satellite routers to the protocol conversion bridge, and assign different IP addresses to the four inter-satellite links of the three satellite routers.

[0155] S3: Utilizing Mininet's dynamic topology adjustment feature, simulate satellite trajectory and link status changes. Network topology is updated in real-time via Python scripts to ensure the simulation environment reflects the actual operational status of the satellite constellation.

[0156] S4: Use ground inspection equipment to configure the parameters of 3 satellite routers respectively. The node numbers are 1, 12 and 23. All of them run the OSPF routing protocol to enable them to operate normally.

[0157] Repeat steps S6 to S11 in Example 3. With multiple physical nodes connected to the simulation test system, test the network performance, including functional performance indicators such as network setup completion time, routing convergence time, end-to-end latency, bandwidth, packet loss rate, and network security.

[0158] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A large-scale constellation network hardware-in-the-loop simulation and testing system, characterized in that: This includes ground detection equipment, a satellite router, a protocol conversion bridge, and a constellation simulator, all connected in sequence. The ground testing equipment is a ground-based support device for the satellite-borne router. The ground testing equipment sends control commands to the satellite-borne router and monitors and records the parameters of the satellite-borne router, collects the operating data of the satellite-borne router in real time, and displays it through a graphical interface. The onboard router is an equivalent satellite node that performs integrated routing and forwarding of intra-satellite, inter-satellite, and satellite-to-ground data. It supports dynamic routing protocols and automatically updates the routing table when the topology changes. The number of equivalent satellite nodes is at least one. The constellation simulator includes a Mininet simulation platform that simulates satellite network topology and network protocols. The constellation simulator dynamically adjusts the network topology, creates, modifies, and deletes virtual nodes and links in the constellation network. The constellation simulator performs dynamic routing networking with the equivalent satellite nodes and tests the convergence time of dynamic routing when the topology changes. The constellation simulator provides an extensible Python application programming interface for network creation and experimentation and tests end-to-end data transmission latency, network bandwidth, and security policies. The protocol conversion bridge connects the constellation simulator and the onboard router, and performs conversion between Ethernet frame protocol and CCSDS frame protocol. The protocol conversion bridge is equipped with a time-space synchronization engine. The spatiotemporal synchronization engine is used to compensate for the time flow rate difference between the equivalent satellite node and the constellation simulator, calculate the adaptive delay, and broadcast a topology snapshot with an effective timestamp to the equivalent satellite node through an out-of-band channel, triggering the equivalent satellite node to pre-compute the routing table; the spatiotemporal synchronization engine injects adaptive delay into the Mininet simulation platform, and after the delay ends, the entire network enables the new path; All virtual nodes of the constellation simulator and all equivalent satellite nodes are configured on the same IP subnet and run the same network routing protocol, with no awareness or communication between the nodes.

2. The large-scale constellation network hardware-in-the-loop simulation test system according to claim 1, characterized in that: The onboard router includes a power module, a platform management module, and a routing module, which enables the network functions of the satellite nodes and allows them to interact with the simulation platform. The constellation simulator contains a set of parameterized topologies. It supports the OSPF dynamic routing protocol and has a graphical user interface. Users can build and manage virtual networks through scripts. The constellation simulator performs multi-scenario testing and connects to at least two equivalent satellite nodes for network testing. The protocol conversion bridge includes a protocol conversion module, a data encapsulation module, a flow control module, a spatiotemporal synchronization engine, and a protocol consistency sandbox. The protocol conversion module identifies and converts different network protocols, performs conversion between Ethernet frame protocol and CCSDS frame protocol, and supports interoperability of heterogeneous networks. The data encapsulation module encapsulates the data to adapt to the transmission format of the target network; The flow control module is used to avoid network congestion and data loss; The spatiotemporal synchronization engine calculates the adaptive delay, delay = k × T_real, where k is a dynamic margin coefficient, which can be changed by setting the range of k between 1.2 and 1.5; T_real is the OSPF convergence time. The protocol consistency sandbox detects whether the maximum transmission unit (MTU) of the Ethernet frames sent by the virtual node exceeds the carrying capacity of the equivalent satellite node. If it exceeds the limit, the virtual node configuration is automatically corrected, and the virtual node is forced to fragment.

3. The large-scale constellation network hardware-in-the-loop simulation test system according to claim 2, characterized in that: The multi-scenario tests include satellite constellation networking scenarios, network performance testing scenarios, security policy testing scenarios, protocol compatibility testing scenarios, and dynamic topology update scenarios. The satellite constellation networking scenario simulates the networking process of a large-scale satellite constellation, verifying the dynamic changes in network topology and the adaptability of routing protocols. The network performance test scenario tests the end-to-end performance metrics of the network and evaluates the network's performance under different load conditions. The end-to-end performance metrics include latency, bandwidth, and packet loss rate. The security strategy test scenario simulates security threats and verifies the security strategies and protection mechanisms of the satellite network. The security threats include network attacks, unauthorized node access, and unauthorized data transmission. The protocol compatibility test scenario verifies the alignment of MTU and QoS behavior between CCSDS and the Ethernet protocol stack through the protocol consistency sandbox, thereby verifying the interoperability of heterogeneous networks. The dynamic topology update scenario simulates link interruption and recovery caused by satellite motion, tests the network's dynamic adaptability and routing convergence time, and performs atomic switching of the routing tables between the virtual node and the equivalent satellite node through a spatiotemporal synchronization engine, with a convergence time difference ≤ 5ms.

4. A semi-physical simulation testing method for large-scale constellation networks, characterized in that: Includes the following steps: S1. Connect the constellation simulator, protocol conversion bridge, satellite router and ground detection equipment in sequence, wherein the satellite router is an equivalent satellite node; S2. Create a virtual topology of the constellation network on the constellation simulator where the Mininet simulation platform is deployed. The virtual topology includes satellite nodes, links, and ground stations. Configure the network topology according to the design parameters of the satellite constellation to obtain virtual nodes. The network topology includes orbital altitude, number of satellites, and link bandwidth. S3. Use the Mininet simulation platform to perform dynamic topology adjustments and simulate the satellite's motion trajectory and link status changes. Update the network topology in real time using Python scripts so that the simulation environment reflects the actual operating status of the satellite constellation. S4. Configure all the virtual nodes and the equivalent satellite nodes in the same IP subnet, set the link port IP address, so that the virtual nodes and the equivalent satellite nodes can communicate directly based on the IP layer; S5. Use the ground inspection equipment to configure the parameters of the spaceborne router, monitor the OSPF convergence time T_real of the spaceborne router, and ensure that the spaceborne router is in normal operation. The parameters of the spaceborne router include node information, orbit information, and link information. S6. Set port information and protocol conversion rules in the protocol conversion bridge so that the ports connected to the satellite router and the protocol conversion bridge correspond one-to-one with the ports connected to the constellation simulator, and perform seamless conversion between Ethernet frames and CCSDS frames. Enable the protocol consistency sandbox in the protocol conversion bridge to detect and calibrate the differences in MTU, QoS marking, and routing calculation parameters between the virtual node and the equivalent satellite node in real time; S7. Verify the routing and networking capability between the virtual node and the equivalent satellite node: Enable the OSPF dynamic routing protocol of the constellation simulator and the on-board router, record the start time T0, perform dynamic routing and networking between the virtual node and the equivalent satellite node, and the networking completion time is T1. Then, the time required for all satellites to complete networking is T = T1 - T0. S8. The spatiotemporal synchronization engine in the protocol conversion bridge broadcasts a snapshot of the topology, including a specified effective timestamp T+delay, to the equivalent satellite node, where delay is the adaptive delay, delay = k × T_real, and k is the dynamic margin coefficient; the Mininet simulation platform injects the adaptive delay and updates the topology, and the equivalent satellite node atomically enables the pre-computed routing table at time T+delay; the routing convergence time difference Δt between the virtual node and the equivalent satellite node is recorded through the graphical interface of the onboard router to evaluate the dynamic adaptability; S9. Select any two nodes in the network, align the traffic parameters through the protocol consistency sandbox, and test the network's end-to-end latency, bandwidth, and packet loss rate to evaluate the network's performance under different load conditions. S10. Simulate security threats between the equivalent satellite node and the virtual node to verify the security strategy and protection mechanism of the satellite network. The security threats include network attacks, unauthorized node access, and unauthorized data transmission. S11. Connect at least two of the equivalent satellite nodes to test the transmission delay, network bandwidth, and effectiveness of security policies for end-to-end data between any two nodes in the network. This completes a semi-physical simulation test method for a large-scale constellation network.

5. The method for hardware-in-the-loop simulation testing of a large-scale constellation network according to claim 4, characterized in that: The Ethernet frame to CCSDS frame conversion process in step S6 includes the following steps: SA1. Receive Ethernet frames and parse IP data packets: The protocol conversion module of the protocol conversion bridge receives Ethernet frames from the constellation simulator, parses the Ethernet frames, and extracts IP data packets. The parsing process includes identifying the Ethernet frame header information and extracting the IP data packet content. The Ethernet frame header information includes the source MAC address, destination MAC address, and protocol type. SA2. Encapsulate IP packets into CCSDS frames: The extracted IP packets are encapsulated according to the CCSDS protocol standard. CCSDS frame header information is added to the header of the IP packets to obtain the encapsulated CCSDS frames. The encapsulated CCSDS frames are checked and encoded. The CCSDS frame header information includes a synchronization word, frame length, sequence number, and data field. SA3. Sending CCSDS frames to the onboard router: The encapsulated CCSDS frames are sent to the onboard router via the physical link. During the transmission process, the flow control module of the protocol conversion bridge monitors the link status. The onboard router receives the encapsulated CCSDS frames and performs decapsulation processing to recover the original IP data packets.

6. The method for semi-physical simulation testing of large-scale constellation networks according to claim 4, characterized in that: The conversion process from CCSDS frames to Ethernet frames in step S6 includes the following steps: SB1. Receiving CCSDS frames and parsing IP data packets: The protocol conversion module of the protocol conversion bridge receives CCSDS frames from the onboard router, parses the CCSDS frames, extracts the IP data packets, and performs integrity verification. The parsing process includes identifying the CCSDS frame header information and extracting the IP data packet content. The CCSDS frame header information includes a synchronization word, frame length, and sequence number. SB2. Encapsulate IP packets into Ethernet frames: According to the Ethernet protocol standard, the extracted IP packets are encapsulated to obtain encapsulated Ethernet frames, and then checked and encoded. The encapsulation process includes adding Ethernet frame header information to the header of the IP packets. The Ethernet frame header information includes the source MAC address, destination MAC address, and protocol type. SB3. Send the encapsulated Ethernet frame to the ground network: The encapsulated Ethernet frame is sent to the constellation simulator through a physical link. During the transmission process, the flow control module of the protocol conversion bridge monitors the link status. The constellation simulator receives the encapsulated Ethernet frame and performs decapsulation processing to recover the original IP data packet.

7. The method for hardware-in-the-loop simulation testing of a large-scale constellation network according to claim 4, characterized in that: The detailed test results for the S9 are as follows: S91. Configure the specified network topology on the Mininet simulation platform, including satellite nodes, ground stations, and links; set the link delay, bandwidth, and packet loss rate to simulate the transmission conditions of a real satellite network. S92. Use a network traffic generation tool to generate different types of traffic between any two nodes in the network. Record network performance indicators, including end-to-end latency, throughput, and packet loss rate, through the real-time monitoring function of the Mininet simulation platform. The protocol consistency sandbox detects whether the maximum transmission unit (MTU) of the Ethernet frames sent by the virtual node exceeds the carrying capacity of the equivalent satellite node. If it exceeds the limit, automatically correct the virtual node configuration and force the virtual node to fragment. S93. Analyze test data, evaluate network performance under different load conditions, display the changing trends of performance indicators through a graphical user interface, and optimize network configuration.

8. The method for hardware-in-the-loop simulation testing of a large-scale constellation network according to claim 4, characterized in that: Step S8 includes the following steps: S81. All nodes in the network run the OSPF dynamic routing protocol to simulate link interruption or recovery caused by satellite motion on the Mininet simulation platform. At the same time, the spatiotemporal synchronization engine automatically intercepts the event and generates an event ID. S82. Collect the historical value T_real of the equivalent satellite node OSPF convergence time through the ground inspection equipment, and calculate the adaptive time delay delay=k*T_real using the spatiotemporal synchronization engine. S83, the spacetime synchronization engine broadcasts a topology snapshot to the equivalent satellite node out of band, including a specified effective timestamp T+delay; S84. After receiving the snapshot, the equivalent satellite node freezes the forwarding plane and suspends data plane forwarding, calculates a new routing table based on the snapshot, and waits for the effective time to switch the routing table. S85. The spatiotemporal synchronization engine injects adaptive time delay into the virtual node, and the virtual node updates the topology after the adaptive time delay ends. S86. Observe the update process of the node routing table in the network. From the link interruption to the recovery, the graphical interface displays the route convergence time axis comparison chart and topology switching atomicity status flag of the virtual node and the equivalent satellite node in real time. The atomicity status flag includes synchronization success and synchronization failure.

9. The method for semi-physical simulation testing of large-scale constellation networks according to claim 4, characterized in that: Step S10 includes the following steps: S101. Configure security policies in the simulation environment, including node access authentication rules and firewall rules; S102. Use security testing tools to simulate network attacks and monitor the network security status in real time through a graphical user interface. Network attacks include any one or more of the following: DDoS attacks, data tampering, and unauthorized access. S103. Assess the network's ability to defend against attacks. Through log analysis and performance indicator monitoring, determine whether the security policy can prevent attacks and protect the normal operation of the network.

10. A semi-physical simulation testing method for large-scale constellation networks according to claim 4, characterized in that: Step S11 includes the following steps: S111. Construct the virtual topology of a large-scale constellation network on the Mininet simulation platform, and configure the network topology to simulate the operating environment of an actual satellite constellation; S112. Connect at least two of the aforementioned satellite routers as equivalent satellite nodes to the simulation platform, and perform protocol conversion and data interaction between the equivalent satellite nodes and the virtual network through the protocol conversion bridge; S113. Configure each of the equivalent satellite nodes, including IP address allocation, routing protocol settings and security policy configuration, so that all nodes can communicate normally and participate in network testing; S114. Use a network traffic generation tool to generate different types of data traffic between any two nodes in the network, and test the end-to-end data transmission latency, network bandwidth, and the effectiveness of security policies between any two nodes in the network. The protocol consistency sandbox unifies the traffic parameter MTU.

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