Event scheduling based satellite network hop time simulation method, system and device

Abstract

The application provides a satellite network time hopping simulation method, system and device based on event scheduling, which comprises the following steps: sequencing and storing events according to the simulation time of topology and link attribute change events; registering and establishing a mapping relationship between real time and simulation time; performing a simulation running step on the event sequence, which comprises the following steps: scheduling the event sequence based on the mapping relationship; determining whether a jump request initiated by a user is received; if the target simulation time and the jump request are received, dividing the event sequence into a historical event set and a future event set; screening the historical event set to obtain a target historical event and performing the target network state reconstruction; remapping and registering the future event set; synchronizing the target network state to make the protocol converge to the target network state, and performing the simulation running step. The application can effectively solve the problem of low simulation efficiency and insufficient flexibility of the existing satellite network virtualization simulation platform in a long time scale.

Description

Technical Field

[0001] This application relates to the fields of network simulation and satellite communication, and in particular to a satellite network time-hop simulation method, system and device based on event scheduling. Background Technology

[0002] With the continuous expansion of low-Earth orbit (LEO) satellite constellations, satellite networks have become a crucial infrastructure for global communications, emergency communications, and access in remote areas. Due to the high-speed motion of LEO satellites, the topology of satellite networks, as well as the connectivity and link attributes of inter-satellite and satellite-to-ground links, change continuously over time. Network performance evaluation and protocol verification are highly dependent on network simulation platforms capable of accurately characterizing the time-varying characteristics of the topology.

[0003] In existing research, modeling and verification of satellite networks typically employ discrete event-based network simulation or virtualization-based network simulation. Discrete event-based network simulation tools usually model network protocols and link states in an event-driven manner, efficiently advancing simulation time and describing the evolution of satellite network topology over time. A typical tool is the Network Simulator 3 (NS-3), which describes network protocol processing, packet sending and receiving behavior, and link state changes through discrete events, making it suitable for large-scale network behavior analysis. However, these tools often use abstract protocol models, making it difficult to fully reflect the operational characteristics of real operating system network protocol stacks in complex and dynamic scenarios. On the other hand, network simulation platforms based on virtualization or container technology can run network protocols on real operating system protocol stacks, reproducing network topology through virtual nodes and virtual links, offering a significant advantage in terms of protocol behavior realism. Existing virtualization simulation tools (such as Mininet) have been widely used in general network research, but their ability to characterize the characteristics of satellite networks, such as high-speed movement and frequent changes in links, is still limited. In the study of satellite network evolution over long time scales, the topology is usually advanced step by step in a manner consistent with actual time.

[0004] In the aforementioned real-time simulation platforms, simulation time is typically tightly bound to actual runtime, requiring the simulation system to execute topology and link attribute change events sequentially. When the simulation timescale is long or the user is only interested in a specific time interval, a large number of time periods unrelated to the research objective still need to be executed completely, resulting in low simulation efficiency and insufficient flexibility. Therefore, there is an urgent need for a technical solution that enables flexible time jumps in real-time satellite network simulation platforms to improve the efficiency and operability of long-scale satellite network research. Summary of the Invention

[0005] In view of this, embodiments of this application provide a satellite network time hop simulation method, system, and device based on event scheduling to eliminate or improve one or more defects existing in the prior art.

[0006] The first aspect of this application provides a time-hop simulation method for satellite networks based on event scheduling, the method comprising: Generate topology and link attribute change events based on the orbital motion patterns of the satellite network; The events are sorted according to their simulation time to obtain an event sequence and then stored. Each node is created and a real network protocol stack is run on each node to obtain the original network state. The event sequence is registered and a mapping relationship is established between the real time corresponding to each event in the event sequence and the simulation time corresponding to each event in the event sequence. The nodes include satellite nodes and ground nodes. The simulation execution steps for the event sequence are based on the mapping relationship. These steps include: scheduling the event sequence based on the mapping relationship; determining whether a user-initiated simulation time jump request has been received; if a user-specified target simulation time and the jump request are received, dividing the event sequence into a historical event set and a future event set based on the target simulation time; filtering the historical event set based on the network link interface to obtain a target historical event, executing the target historical event to reconstruct the network state corresponding to the target simulation time, and obtaining the target network state; and remapping and registering the future event set based on the target simulation time. The target network state is synchronized so that the network protocol stack converges the protocol corresponding to the original network state to the target network state, and the simulation operation steps are executed.

[0007] In some embodiments of this application, the event scheduling step further includes: If the user-specified simulation time and jump request are not received, the simulation time will be kept synchronized with the real time, the event sequence will be continuously scheduled and executed, the current network status will be updated in real time, and relevant status and log information during the simulation process will be recorded. Perform the simulation run steps.

[0008] In some embodiments of this application, generating topology and link attribute change events based on the orbital motion patterns of the satellite network includes: Model the changes in link connectivity and link attributes between each of the satellite nodes and between the satellite nodes and the ground nodes within the simulation time range; The changes are abstracted into topology and link attribute change events with time stamps; wherein, the topology and link attribute change events include link establishment events, link disconnection events, and link parameter update events.

[0009] In some embodiments of this application, the event sequence is stored using a nested mapping structure, which includes: The link interface has a unique identifier and the event trigger time, which are used to quickly retrieve events.

[0010] In some embodiments of this application, before performing the simulation run step on the event sequence based on the mapping relationship, the method further includes: The simulation time of each event in the event sequence is converted into a delay time; The delay time is submitted as a delay task to the scheduling thread pool so that the delay queue mechanism in the scheduling thread pool can automatically complete the time sorting and trigger control. Generate a task control object corresponding to each of the delayed tasks; wherein the task control object is used to represent the execution status of the task and supports querying the remaining delay time, querying the execution status, canceling the scheduling operation, and rescheduling the operation.

[0011] In some embodiments of this application, dividing the event sequence into a set of historical events and a set of future events based on the target simulation time includes: Obtain the set of task control objects and calculate the jump interval based on the target simulation time; Iterate through the set of task control objects and query the remaining delay time of each task control object in the set of task control objects; Events corresponding to task control objects whose remaining delay time is greater than the time jump interval are assigned to the future event set, and events corresponding to task control objects whose remaining delay time is less than or equal to the time jump interval are assigned to the historical event set; wherein, the historical event set includes events in the event sequence whose simulation time is earlier than or equal to the target simulation time, and the future event set includes events in the event sequence whose simulation time is later than the target simulation time.

[0012] In some embodiments of this application, the step of remapping and registering the set of future events based on the target simulation time includes: The target delay time is obtained based on the target simulation time and the remaining delay time corresponding to each event in the set of future events. The set of future events is remapped and registered based on the target delay time.

[0013] A second aspect of this application provides a satellite network time hop simulation system based on event sequences, comprising: The event generation module is used to generate topology and link attribute change events based on the orbital motion patterns of the satellite network. The event sequence management module is used to sort the events according to their simulation time to obtain an event sequence and store it. The simulation platform initialization module is used to create various nodes and run real network protocol stacks on each node to obtain the original network state, register the event sequence, and establish a mapping relationship between the real time corresponding to each event in the event sequence and the simulation time corresponding to each event in the event sequence; wherein, the nodes include satellite nodes and ground nodes; An event scheduling module is used to execute simulation operation steps on the event sequence based on the mapping relationship. The simulation operation steps include: scheduling the event sequence based on the mapping relationship; determining whether a simulation time jump request initiated by a user is received; if a target simulation time specified by the user and the jump request are received, dividing the event sequence into a historical event set and a future event set based on the target simulation time; filtering the historical event set based on the network link interface to obtain a target historical event, executing the target historical event to reconstruct the network state corresponding to the target simulation time, and obtaining the target network state; and remapping and registering the future event set based on the target simulation time. The protocol execution and state maintenance module is used to synchronize the target network state so that the network protocol stack converges the protocol corresponding to the original network state to the target network state and executes the simulation execution steps.

[0014] A third aspect of this application provides an electronic device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the aforementioned event-based satellite network time-hopping simulation method.

[0015] A fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the aforementioned event-based satellite network time-hopping simulation method.

[0016] The fifth aspect of this application provides a computer program product comprising a computer program that, when executed by a processor, implements the event-based time-hopping simulation method for satellite networks described in the first aspect.

[0017] This application provides a time-hop simulation method for satellite networks based on event scheduling. The method includes: generating topology and link attribute change events according to the orbital motion patterns of the satellite network; sorting the events according to their simulation times to obtain an event sequence and storing it; creating nodes and running a real network protocol stack on each node to obtain the original network state; registering the event sequence and establishing a mapping relationship between the real time corresponding to each event in the event sequence and the simulation time corresponding to each event in the event sequence; wherein the nodes include satellite nodes and ground nodes; and executing simulation operation steps on the event sequence based on the mapping relationship, the simulation operation steps including... The process involves: scheduling the event sequence based on the mapping relationship; determining whether a simulation time jump request initiated by a user has been received; if a target simulation time specified by the user and the jump request are received, dividing the event sequence into a historical event set and a future event set based on the target simulation time; filtering the historical event set based on the network link interface to obtain a target historical event, executing the target historical event to reconstruct the network state corresponding to the target simulation time, and obtaining the target network state; remapping and registering the future event set based on the target simulation time; synchronizing the target network state to enable the network protocol stack to converge the protocol corresponding to the original network state to the target network state, and executing the simulation operation steps. By abstracting the time-varying topology and link attribute changes of satellite networks into event sequences and implementing simulation time jumps based on event scheduling, this method avoids a large amount of invalid continuous time advancement in traditional real-time simulations, significantly reducing the real time required for simulation and improving the efficiency of long-scale simulations. Users can directly jump to the simulation time point or time interval of interest according to actual needs, improving the flexibility and controllability of satellite network protocol verification and performance evaluation. Running a real network protocol stack on a real-time virtualization simulation platform, while achieving time-jump simulation, does not destroy the protocol's own operating logic and convergence characteristics, ensuring the authenticity of protocol operation. At the same time, the method proposed in this application is suitable for satellite network scenarios with highly dynamic topologies, such as low-Earth orbit satellite networks, providing an efficient and scalable simulation means for the research and verification of complex satellite networks.

[0018] Additional advantages, objectives, and features of this application will be set forth in part in the description which follows, and will in part become apparent to those skilled in the art upon review of the following description, or may be learned by practice of the application. The objectives and other advantages of this application can be realized and obtained by means of the structures specifically pointed out in the specification and drawings.

[0019] Those skilled in the art will understand that the purposes and advantages that can be achieved with this application are not limited to those specifically described above, and that the above and other purposes that this application can achieve will be more clearly understood from the following detailed description. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, do not constitute a limitation thereof. The components in the drawings are not drawn to scale but are merely for illustrating the principles of this application. For ease of illustration and description of certain parts of this application, corresponding portions in the drawings may be enlarged, i.e., may appear larger relative to other components in an exemplary device actually manufactured according to this application. In the drawings: Figure 1 This is a flowchart illustrating an event-based time-hopping simulation method for satellite networks according to one embodiment of this application.

[0021] Figure 2 This is a flowchart illustrating the event-based time-hopping simulation method for satellite networks in an application example of this application.

[0022] Figure 3 This is a schematic diagram of the architecture of a satellite network time-hopping simulation system based on event scheduling in an application example of this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and their descriptions are used to explain this application, but are not intended to limit it.

[0024] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the structures and / or processing steps closely related to the solution according to this application are shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0025] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, element, step, or component, but does not exclude the presence or addition of one or more other features, elements, steps, or components.

[0026] It should also be noted that, unless otherwise specified, the term "connection" in this article can refer not only to a direct connection, but also to an indirect connection involving an intermediary.

[0027] In the following description, embodiments of the present application will be illustrated with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar parts, or the same or similar steps.

[0028] To address the issues of low simulation efficiency and insufficient flexibility in existing satellite network virtualization simulation platforms over long timescales, this application provides an event-scheduling-based satellite network time-hopping simulation method, an event-scheduling-based satellite network time-hopping simulation system, an electronic device, a computer-readable storage medium, and a computer program product, respectively, to improve simulation efficiency over long timescales and enhance simulation flexibility and controllability.

[0029] The following examples will provide a detailed description.

[0030] Based on this, embodiments of this application provide an event-scheduling-based satellite network time hop simulation method that can be executed by an event-scheduling-based satellite network time hop simulation device. See [link to relevant documentation]. Figure 1 The method specifically includes the following: Step 100: Generate topology and link attribute change events based on the orbital motion patterns of the satellite network.

[0031] It is understood that the events specifically refer to the changes in the on / off state (up / down) of links in the satellite network and the changes in link attributes (latency, bandwidth, packet loss rate, etc.). These events can be scheduled and executed during the simulation process, and the specific implementation methods will be described in detail in the subsequent embodiments.

[0032] Step 200: Sort the events according to their simulation time to obtain an event sequence and store it.

[0033] It should also be noted that the generated topology and link attribute change events are sorted according to the simulation time sequence of the events, forming a time-ordered event sequence. To support large-scale constellations and long-term simulations, this event sequence can be stored in a JSON file or a database, and loaded into the in-memory event sequence management module by the background service during the simulation startup phase for subsequent event scheduling and time-skip processing.

[0034] The simulation time of an event represents the relative time with respect to the simulation start time (0s). All of the above events are used to characterize the evolution of the network state throughout the entire simulation cycle. The event sequence management module is one of the modules in another embodiment of a satellite network time-hop simulation system based on event scheduling.

[0035] Step 300: Create each node and run the real network protocol stack on each node to obtain the original network state, register the event sequence and establish a mapping relationship between the real time corresponding to each event in the event sequence and the simulation time corresponding to each event in the event sequence; wherein, the nodes include satellite nodes and ground nodes.

[0036] It should be noted that corresponding satellite node instances and ground node instances are created in the real-time virtualization simulation platform, and a real network protocol stack runs on each node. Simultaneously, the topology and link attribute change event sequences are registered to the event scheduling module, establishing a mapping relationship between the real event time and the simulation time, thus entering a continuous running state. In this state, event scheduling and network protocol operation proceed in parallel. The event sequence scheduling module is one module in another embodiment of a satellite network time-hop simulation system based on event scheduling.

[0037] Step 400: Perform simulation execution steps on the event sequence based on the mapping relationship. The simulation execution steps include: scheduling the event sequence based on the mapping relationship; determining whether a simulation time jump request initiated by a user is received; if a target simulation time specified by the user and the jump request are received, dividing the event sequence into a historical event set and a future event set based on the target simulation time; filtering the historical event set based on the network link interface to obtain a target historical event, executing the target historical event to reconstruct the network state corresponding to the target simulation time, and obtaining the target network state; remapping and registering the future event set based on the target simulation time.

[0038] Specifically, the event scheduling module schedules and executes topology and link attribute change events based on the one-to-one mapping between simulation time and real time. Simultaneously, the network protocol stack continues to run, sensing the current network topology state and executing corresponding protocol logic. During operation, it can periodically or on demand determine whether a user-initiated simulation time jump request has been received.

[0039] When a simulation time jump request is received from a user and a target simulation time is specified... When the time jump rescheduling process begins, it will proceed to the target simulation time. As a time reference point, the sequence of topology and link attribute change events is analyzed, and the events are divided into a historical event set and a future event set. The historical event set includes all events that occurred earlier than or equal to... The set of future events includes all events that occur later than [date / time]. The incident.

[0040] Simultaneously, the historical event set is filtered at the object level, using network link interfaces as units. For each link or interface, the topology and link attribute change event closest to the target simulation time (i.e., the target historical event) is recorded, and this event is directly executed in the simulation platform to quickly reconstruct the network topology and link attribute state corresponding to the target simulation time. After completing the target network state reconstruction, the target simulation time is used as the basis for further analysis. Using the new time reference point, the event trigger times in the future event set are remapped, and the events are re-registered to the event scheduling module to enable continued operation from the target simulation time.

[0041] It should also be noted that the execution of the aforementioned events can be achieved by calling the underlying network control interface of the operating system. In one implementation, virtual satellite nodes can be constructed based on the Linux network namespace mechanism, and connections between nodes can be achieved through virtual Ethernet interface pairs. When a link topology change event is executed, the on / off state (up / down) of the link can be switched by modifying the enabled state of the corresponding virtual network interface; when a link attribute change event is executed, the network simulation queue rules for the corresponding virtual interface can be loaded or updated by calling the kernel flow control mechanism to dynamically adjust parameters such as link latency, bandwidth, or packet loss rate. Essentially, the link state can be dynamically modified by calling the underlying application programming interface (API) of the operating system.

[0042] Step 500: Synchronize the target network state so that the network protocol stack converges the protocol corresponding to the original network state to the target network state, and execute the simulation operation steps.

[0043] Specifically, after the time-skip operation is completed, a state synchronization phase is introduced, which enables the real network protocol stack running in the simulation platform to complete the perception and initial convergence of the network state under the current network conditions. Then, it returns to step 400 to continue the simulation process.

[0044] During the state synchronization phase, changes in network topology and link attributes are accomplished through the operating system's underlying network control interface. These link state changes trigger the operating system kernel to generate corresponding network interface state change events, which are then transmitted to the network protocol stack running in user space via a network event notification mechanism. Upon receiving the interface state change notification, the network protocol stack automatically triggers processes such as adjacency reconstruction and route recalculation, thereby achieving protocol convergence under the new network conditions.

[0045] In one implementation, the convergence of critical protocols can be determined by querying the protocol adjacency state or the stability of the routing table before continuing the simulation. In another implementation, a preset state synchronization time window can be set to ensure that the protocol stack completes the necessary convergence process. Through these mechanisms, automatic protocol awareness and smooth transition after time hops can be achieved, avoiding abnormal protocol states caused by topology changes. No additional manual events need to be injected into the protocol stack; the protocol convergence process is entirely automated based on the operating system's standard network event mechanism.

[0046] As described above, the satellite network time-hopping simulation method based on event scheduling provided in this application abstracts the time-varying topology and link attribute changes of the satellite network into event sequences and realizes simulation time jumps based on event scheduling. This avoids a large amount of invalid continuous time advancement in traditional real-time simulation, significantly reduces the real time required for simulation, and improves the efficiency of long-scale simulation. Users can directly jump to the simulation time point or time interval of interest according to actual needs, improving the flexibility and controllability of satellite network protocol verification and performance evaluation. Running a real network protocol stack on a real-time virtualization simulation platform, while realizing time-hopping simulation, does not destroy the protocol's own operating logic and convergence characteristics, ensuring the authenticity of protocol operation. At the same time, the method proposed in this application is suitable for satellite network scenarios with highly dynamic topology changes, such as low-Earth orbit satellite networks, providing an efficient and scalable simulation means for the research and verification of complex satellite networks.

[0047] To further improve the efficiency of long-term simulations and enhance their flexibility and controllability, in a satellite network time-hop simulation method based on event scheduling provided in this application embodiment, step 400 of the event scheduling step further includes the following: Step 600: If the simulation time and jump request specified by the user are not received, the simulation time is kept synchronized with the real time, the event sequence is continuously scheduled and executed, the current network status is updated in real time, and the relevant status and log information during the simulation process are recorded. Step 700: Execute the simulation run steps.

[0048] Specifically, when no simulation time jump request is received, the simulation time is kept synchronized with the real time, topology and link attribute change events are continuously scheduled and executed, the network status is updated in real time, and relevant status and log information during the simulation operation is recorded. Then, the process returns to step 400 to continue running.

[0049] To further improve the efficiency of long-term simulations and enhance their flexibility and controllability, in a satellite network time-hop simulation method based on event scheduling provided in this application embodiment, step 100, which generates topology and link attribute change events according to the orbital motion laws of the satellite network, specifically includes the following: Step 110: Model the changes in link connectivity and link attributes between each satellite node and between the satellite node and the ground node within the simulation time range; Step 120: Abstract the changes into topology and link attribute change events with time stamps; wherein, the topology and link attribute change events include link establishment events, link disconnection events, and link parameter update events.

[0050] Understandably, based on the orbital motion patterns of the satellite network, the changes in link connectivity and link attributes between satellite nodes and between satellite nodes and ground nodes are predicted within the simulation timeframe, and these changes are uniformly abstracted into events with simulation time stamps.

[0051] To further improve the efficiency of long-term simulations and enhance their flexibility and controllability, in a satellite network time-hop simulation method based on event scheduling provided in this application embodiment, in step 200, the event sequence is stored using a nested mapping structure, which specifically includes the following: The link interface has a unique identifier and the event trigger time, which are used to quickly retrieve events.

[0052] Specifically, in memory, event sequences can be stored using a nested mapping structure: the outer Map's key is a unique identifier for the link interface (e.g., S0101-S0102 identifies the network interface card on the S0101 side of the inter-satellite link), and the inner Map's key is the event trigger time, with the value being the corresponding event object, ensuring that events can be quickly retrieved based on interface and time. An event sequence can be represented as: .

[0053] To further improve the efficiency of long-term simulations and enhance the flexibility and controllability of simulations, in a satellite network time-hop simulation method based on event scheduling provided in this application embodiment, before performing the simulation operation steps on the event sequence based on the mapping relationship in step 400, the following content is specifically included: Step 310: Convert the simulation time of each event in the event sequence into a delay time; Step 320: Submit the delay time as a delay task to the scheduling thread pool so that the delay queue mechanism in the scheduling thread pool can automatically complete the time sorting and trigger control; Step 330: Generate task control objects corresponding to each of the delayed tasks; wherein, the task control object is used to represent the execution status of the task and supports querying the remaining delay time, querying the execution status, canceling the scheduling operation, and rescheduling the operation.

[0054] Specifically, in one implementation, the event scheduling module can be based on a thread scheduling framework that supports delayed execution mechanisms. During the initialization phase, the relative times of each event in the event sequence are converted into corresponding delay times and submitted as delayed tasks to the scheduling thread pool. The thread pool's internal delay queue mechanism automatically handles time sorting and trigger control. Each task generates a corresponding task control object after submission, representing its execution status. The task control object supports querying remaining delay time and execution status, and supports cancellation or rescheduling operations.

[0055] To further improve the efficiency of long-term simulations and enhance their flexibility and controllability, in a satellite network time-hop simulation method based on event scheduling provided in this application embodiment, step 400, which divides the event sequence into a set of historical events and a set of future events based on the target simulation time, specifically includes the following: Step 410: Obtain the task control object set and calculate the jump interval based on the target simulation time; Step 420: Traverse the set of task control objects and query the remaining delay time of each task control object in the set of task control objects; Step 430: Assign events corresponding to the task control objects whose remaining delay time is greater than the jump interval to the future event set, and assign events corresponding to the task control objects whose remaining delay time is less than or equal to the jump interval to the historical event set; wherein, the historical event set includes events in the event sequence whose simulation time is earlier than or equal to the target simulation time, and the future event set includes events in the event sequence whose simulation time is later than the target simulation time.

[0056] It should also be noted that a set of scheduled tasks is maintained, which is used to uniformly manage the task control objects corresponding to all events. This set uses the unique identifier of the link interface as the first-level index and the event trigger time as the second-level index, for quickly locating the task control object corresponding to a specific network object event. The set of task control objects can be represented as follows: .

[0057] Specifically, during the time jump process, based on the set of task control objects Perform state determination based on the target simulation time and the time jump initiation time. The difference is used to obtain the jump interval. The task control object set is then iterated through. During the iteration, the remaining delay time of each task control object is checked, and those with a remaining delay time greater than a specified value are selected. The task is divided into a set of future events, with the remaining delay time less than or equal to The tasks are divided into a set of historical events.

[0058] To further improve the efficiency of long-term simulations and enhance their flexibility and controllability, in a satellite network time-hop simulation method based on event scheduling provided in this application embodiment, step 400, which involves remapping and registering the set of future events based on the target simulation time, specifically includes the following: Step 440: Obtain the target delay time based on the target simulation time and the remaining delay time corresponding to each event in the set of future events; Step 450: Remap and register the set of future events according to the target delay time.

[0059] Specifically, for events in the future event set, the remaining delay time of the task object minus the jump interval ΔT is used as the new delay time, and the event is re-registered with the delayed thread scheduling framework.

[0060] To further illustrate the above embodiments, this application also provides a specific application example of a satellite network time-hop simulation method based on event scheduling.

[0061] Existing virtualization simulation platforms lack a unified abstraction and scheduling mechanism for predictable topology and link attribute changes in satellite networks, making it difficult to perform discontinuous control of simulation time while maintaining the operational characteristics of the real network protocol stack. This application aims to provide a technical solution for implementing time-skip simulation in a real-time satellite network virtualization simulation platform. This solution establishes an event sequence corresponding to changes in satellite network topology and link attributes on the simulation platform and schedules the execution of these events based on their time attributes, thereby achieving rapid jumps to user-focused time intervals while maintaining the normal operation of network protocols under specified topology conditions. This application is not a time-advancement optimization as in traditional discrete event simulations, but rather a non-discontinuous relocation of simulation time under the premise of continuous operation of the real network protocol.

[0062] The event-based time-hop simulation method for satellite networks provided in this application example specifically includes the following: This application presents an application example of a time-hop simulation method for satellite networks based on event scheduling. The overall process is as follows: Figure 2As shown, this method switches between the regular event scheduling path and the time-skip rescheduling path during the continuous operation of the simulation system, depending on whether a time-skip request is received. The time-skip request can be initiated by the user specifying a target simulation time in the system's front-end interface, and the system's back-end time-skip function interface automatically responds and triggers the request; essentially, it involves a response between the front-end and back-end interfaces. Specifically, it includes the following steps: Step 1: Modeling topology and link attribute change events; Step 2: Generate and manage event sequences; Step 3: Simulation initialization and runtime environment setup: Register events and establish time mappings; Step 4: Continuous operation and event scheduling of the simulation system: event scheduling and protocol execution; Step 5: Time-skip request judgment: If not, advance the simulation time in real time and execute the event, update the network status and record the log, and execute Step 4; if yes, execute Step 6; Step 6: Event Rescheduling and Time Skip Control: Based on the target simulation time Divide the network into historical and future event sets, filter historical events, retain only the most recent event for each link, and execute to reconstruct the target network state. Future events are set to the target simulation time. Re-register and schedule for the reference point; Step 7: Post-time hop state synchronization and protocol stabilization: The protocol stack becomes aware of the topology and completes initial convergence.

[0063] The application examples in this application mainly include the following: 1. A simulation time jump control mechanism for a real-time virtualized satellite network simulation platform, which, under the premise of continuous operation of the real network protocol stack, establishes and schedules an event sequence for the satellite network topology evolution and link attribute change process to achieve rapid relocation and discontinuous advancement of the simulation time axis.

[0064] 2. An event modeling and sequence management method for changes in satellite network topology and link attributes, which abstracts the changes in link connectivity and link attributes caused by satellite orbital motion into time-stamped events and forms a time-ordered event sequence, so that the network topology state at any simulation time point can be determined by a finite set of events.

[0065] 3. A method for direct reconstruction of time-hopping network state based on event coverage characteristics: When a simulation time jump request is received and a target simulation time is specified, the event sequence is divided into a set of historical events and a set of future events, with the target time as a reference point. Then, based on network links or interfaces, only the most recent topology change event and link attribute change event before the target time are retained. The target time topology and link attributes are quickly constructed by directly executing the events.

[0066] 4. An event remapping and continuous scheduling mechanism after time jump: After the target network state reconstruction is completed, the event triggering time in the future event set is remapped and registered with the target simulation time as the new time reference point, so that the simulation system can continue to run in real time mode from the target time, thereby maintaining the semantic continuity of the simulation time axis.

[0067] 5. An event scheduling architecture running on a real-time virtualization simulation platform, which introduces an independent topology and link attribute event scheduling layer on top of the real network protocol stack. The scheduling layer only acts on changes in network topology and link attributes, and after time-hop operations, it ensures the protocol's awareness of the current network state and stable operation through a state synchronization mechanism.

[0068] The application examples of this application have at least the following beneficial effects: 1. Improve the efficiency of long-term simulation: By abstracting the time-varying topology and link attribute changes of satellite networks into event sequences and realizing simulation time jumps based on event scheduling, a large number of invalid continuous time advances in traditional real-time simulations are avoided, significantly reducing the real time required for simulation.

[0069] 2. Enhance simulation flexibility and controllability: Users can directly jump to the simulation time point or time interval of interest according to actual needs, improving the flexibility of satellite network protocol verification and performance evaluation.

[0070] 3. Maintaining the authenticity of protocol operation: This invention runs a real network protocol stack on a real-time virtualization simulation platform, achieving time-hopping simulation without destroying the protocol's own operating logic and convergence characteristics.

[0071] 4. Applicable to highly dynamic satellite network scenarios: This technical solution is particularly suitable for scenarios with highly dynamic topology changes, such as low-Earth orbit satellite networks, providing an efficient and scalable simulation method for the research and verification of complex satellite networks.

[0072] This application also provides an event-based satellite network time-hop simulation system, which specifically includes the following: The event generation module is used to generate topology and link attribute change events based on the orbital motion patterns of the satellite network. The event sequence management module is used to sort the events according to their simulation time to obtain an event sequence and store it. The simulation platform initialization module is used to create various nodes and run real network protocol stacks on each node to obtain the original network state, register the event sequence, and establish a mapping relationship between the real time corresponding to each event in the event sequence and the simulation time corresponding to each event in the event sequence; wherein, the nodes include satellite nodes and ground nodes; An event scheduling module is used to execute simulation operation steps on the event sequence based on the mapping relationship. The simulation operation steps include: scheduling the event sequence based on the mapping relationship; determining whether a simulation time jump request initiated by a user is received; if a target simulation time specified by the user and the jump request are received, dividing the event sequence into a historical event set and a future event set based on the target simulation time; filtering the historical event set based on the network link interface to obtain a target historical event, executing the target historical event to reconstruct the network state corresponding to the target simulation time, and obtaining the target network state; and remapping and registering the future event set based on the target simulation time. The protocol execution and state maintenance module is used to synchronize the target network state so that the network protocol stack converges the protocol corresponding to the original network state to the target network state and executes the simulation execution steps.

[0073] It is understood that the specific implementation of the satellite network time hop simulation system based on event scheduling provided in this application can correspond one-to-one with the processing flow of the satellite network time hop simulation method based on event scheduling in the above embodiments. Its functions will not be repeated here, but can be referred to the detailed description of the satellite network time hop simulation method based on event scheduling in the above embodiments.

[0074] As can be seen from the above description, the satellite network time-hopping simulation system based on event scheduling provided in this application embodiment can achieve discontinuous advancement of simulation time while maintaining the actual network protocol stack operation logic.

[0075] To further illustrate the above embodiments, this application also provides a specific application example of an event-based satellite network time-hop simulation system, which specifically includes the following: This system can run on a real-time virtualization simulation platform. The architecture diagram of the satellite network time hop simulation system is as follows: Figure 3 As shown, the system generally includes, but is not limited to, the following functional modules: (1) Simulation platform initialization module The simulation platform initialization module is used to build a simulation operating environment for the satellite network. It provides isolated network protocol operating spaces for each satellite node and ground node through virtualization or containerization technology, enabling the network protocol to run in the form of a real operating system protocol stack.

[0076] This module provides the basic operating environment for the entire simulation system and supports dynamic configuration of node network interfaces, link connectivity status, and link attributes.

[0077] (2) Event generation module The event generation module is used to pre-generate a sequence of topology and link attribute change events associated with the simulation time, based on the time-varying characteristics of the satellite network.

[0078] Specifically, based on the satellite orbital motion prediction results, this module models the changes in link connectivity and link attributes between satellites and between satellites and ground nodes, and abstracts these changes into time-stamped events, including but not limited to link establishment events, link disconnection events, and link parameter update events.

[0079] (3) Event Sequence Management Module The event sequence management module is used to uniformly manage topology and link attribute change events, sort these events according to their occurrence time, and form a time-ordered event sequence.

[0080] This module supports filtering, truncating, or rearranging event sequences based on user-defined simulation start time, target time, or time interval of interest, providing a basis for subsequent event scheduling.

[0081] (4) Event scheduling module The event scheduling module is used to schedule the execution of topology and link attribute change events according to the time attributes of each event in the event sequence during the simulation operation.

[0082] During the simulation time progression, this module can directly trigger the corresponding topology change operation according to the event time sequence without relying on continuous real-time progression, enabling the simulation system to switch directly from the current simulation time state to the network state corresponding to the target simulation time.

[0083] (5) Protocol operation and state maintenance module The protocol operation and state maintenance module is used to maintain the continuous operation of the real network protocol stack in each network node before and after the execution of topology and link attribute change events.

[0084] After the network state changes, this module allows the network protocol to perform normal protocol interaction and state convergence under the new network conditions.

[0085] This application also provides an electronic device, which may include a processor, a memory, a receiver, and a transmitter. The processor is used to execute the event-scheduling-based satellite network time-hop simulation method mentioned in the above embodiments. The processor and memory can be connected via a bus or other means, taking a bus connection as an example. The receiver can be connected to the processor and memory via wired or wireless means.

[0086] The processor can be a central processing unit (CPU). The processor can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips.

[0087] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the event-scheduling-based satellite network time-hopping simulation method in the embodiments of this application. The processor executes various functional applications and data processing by running the non-transitory software programs, instructions, and modules stored in the memory, thereby implementing the event-scheduling-based satellite network time-hopping simulation method in the above method embodiments.

[0088] The memory may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created by the processor, etc. Furthermore, the memory may include high-speed random access memory and non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory may optionally include memory remotely located relative to the processor, which can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0089] The one or more modules are stored in the memory, and when executed by the processor, they perform the event-based time-hopping simulation method for satellite networks in the embodiment.

[0090] In some embodiments of this application, the user equipment may include a processor, a memory, and a transceiver unit. The transceiver unit may include a receiver and a transmitter. The processor, memory, receiver, and transmitter may be connected via a bus system. The memory is used to store computer instructions, and the processor is used to execute the computer instructions stored in the memory to control the transceiver unit to send and receive signals.

[0091] As one implementation method, the functions of the receiver and transmitter in this application can be implemented by transceiver circuits or dedicated transceiver chips, and the processor can be implemented by dedicated processing chips, processing circuits or general-purpose chips.

[0092] As another implementation approach, the server provided in this application embodiment can be implemented using a general-purpose computer. That is, the program code implementing the processor, receiver, and transmitter functions is stored in memory, and the general-purpose processor implements the processor, receiver, and transmitter functions by executing the code in memory.

[0093] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the aforementioned event-based satellite network time-hop simulation method. The computer-readable storage medium can be a tangible storage medium, such as random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, floppy disks, hard disks, removable storage disks, CD-ROMs, or any other form of storage medium known in the art.

[0094] This application also provides a computer program product, specifically including a computer program that, when executed by a processor, implements the steps of the event-based satellite network time-hopping simulation method mentioned in the foregoing embodiments.

[0095] Those skilled in the art will understand that the exemplary components, systems, and methods described in conjunction with the embodiments disclosed herein can be implemented in hardware, software, or a combination of both. Whether implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application. When implemented in hardware, it can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. The programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave.

[0096] It should be clarified that this application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this application is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this application.

[0097] In this application, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or in place of features of other embodiments.

[0098] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to the embodiments of this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A satellite network time-hop simulation method based on event scheduling, characterized in that, The method includes: Generate topology and link attribute change events based on the orbital motion patterns of the satellite network; The events are sorted according to their simulation time to obtain an event sequence and then stored. Each node is created and a real network protocol stack is run on each node to obtain the original network state. The event sequence is registered and a mapping relationship is established between the real time corresponding to each event in the event sequence and the simulation time corresponding to each event in the event sequence. The nodes include satellite nodes and ground nodes. The simulation execution steps for the event sequence are based on the mapping relationship. These steps include: scheduling the event sequence based on the mapping relationship; determining whether a user-initiated simulation time jump request has been received; if a user-specified target simulation time and the jump request are received, dividing the event sequence into a historical event set and a future event set based on the target simulation time; filtering the historical event set based on the network link interface to obtain a target historical event, executing the target historical event to reconstruct the network state corresponding to the target simulation time, and obtaining the target network state; and remapping and registering the future event set based on the target simulation time. The target network state is synchronized so that the network protocol stack converges the protocol corresponding to the original network state to the target network state, and the simulation operation steps are executed.

2. The satellite network time-hop simulation method based on event scheduling according to claim 1, characterized in that, The event scheduling step also includes: If the user-specified simulation time and jump request are not received, the simulation time will be kept synchronized with the real time, the event sequence will be continuously scheduled and executed, the current network status will be updated in real time, and relevant status and log information during the simulation process will be recorded. Perform the simulation run steps.

3. The satellite network time-hop simulation method based on event scheduling according to claim 1, characterized in that, The generation of topology and link attribute change events based on the orbital motion patterns of the satellite network includes: Model the changes in link connectivity and link attributes between each of the satellite nodes and between the satellite nodes and the ground nodes within the simulation time range; The changes are abstracted into topology and link attribute change events with time stamps; wherein, the topology and link attribute change events include link establishment events, link disconnection events, and link parameter update events.

4. The satellite network time-hop simulation method based on event scheduling according to claim 1, characterized in that, The event sequence is stored using a nested mapping structure, which includes: The link interface has a unique identifier and the event trigger time, which are used to quickly retrieve events.

5. The satellite network time-hop simulation method based on event scheduling according to claim 1, characterized in that, Before performing the simulation run step on the event sequence based on the mapping relationship, the method further includes: The simulation time of each event in the event sequence is converted into a delay time; The delay time is submitted as a delay task to the scheduling thread pool so that the delay queue mechanism in the scheduling thread pool can automatically complete the time sorting and trigger control. Generate a task control object corresponding to each of the delayed tasks; wherein the task control object is used to represent the execution status of the task and supports querying the remaining delay time, querying the execution status, canceling the scheduling operation, and rescheduling the operation.

6. The satellite network time-hop simulation method based on event scheduling according to claim 1, characterized in that, The process of dividing the event sequence into a set of historical events and a set of future events based on the target simulation time includes: Obtain the set of task control objects and calculate the jump interval based on the target simulation time; Iterate through the set of task control objects and query the remaining delay time of each task control object in the set of task control objects; Events corresponding to task control objects whose remaining delay time is greater than the time jump interval are assigned to the future event set, and events corresponding to task control objects whose remaining delay time is less than or equal to the time jump interval are assigned to the historical event set; wherein, the historical event set includes events in the event sequence whose simulation time is earlier than or equal to the target simulation time, and the future event set includes events in the event sequence whose simulation time is later than the target simulation time.

7. The satellite network time-hop simulation method based on event scheduling according to claim 1, characterized in that, The step of remapping and registering the set of future events based on the target simulation time includes: The target delay time is obtained based on the target simulation time and the remaining delay time corresponding to each event in the set of future events. The set of future events is remapped and registered based on the target delay time.

8. A satellite network time hop simulation system based on event sequences, characterized in that, include: The event generation module is used to generate topology and link attribute change events based on the orbital motion patterns of the satellite network. The event sequence management module is used to sort the events according to their simulation time to obtain an event sequence and store it. The simulation platform initialization module is used to create various nodes and run real network protocol stacks on each node to obtain the original network state, register the event sequence, and establish a mapping relationship between the real time corresponding to each event in the event sequence and the simulation time corresponding to each event in the event sequence; wherein, the nodes include satellite nodes and ground nodes; An event scheduling module is used to execute simulation operation steps on the event sequence based on the mapping relationship. The simulation operation steps include: scheduling the event sequence based on the mapping relationship; determining whether a simulation time jump request initiated by a user is received; if a target simulation time specified by the user and the jump request are received, dividing the event sequence into a historical event set and a future event set based on the target simulation time; filtering the historical event set based on the network link interface to obtain a target historical event, executing the target historical event to reconstruct the network state corresponding to the target simulation time, and obtaining the target network state; and remapping and registering the future event set based on the target simulation time. The protocol execution and state maintenance module is used to synchronize the target network state so that the network protocol stack converges the protocol corresponding to the original network state to the target network state and executes the simulation execution steps.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the satellite network time-hopping simulation method based on event sequences as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the event sequence-based satellite network time-hopping simulation method as described in any one of claims 1 to 7.

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