Time-slicing prediction based low earth orbit satellite network SDN routing update method, routing update packet generation and sending method, satellite routing flow table receiving and switching method, satellite routing controller

Abstract

The application provides a low-orbit satellite network SDN routing update method based on time slice prediction, a routing update package generation and sending method, a satellite routing flow table receiving and switching method, and a satellite routing controller. The method obtains satellite node orbit dynamics parameters and calculates the evolution trend of the whole network topology through the satellite routing controller to generate a division sequence of time steps. Based on the division sequence, the whole network topology snapshot is constructed and the global routing flow table is generated, and then the routing update package is generated. The update package is uploaded to the target satellite node, and in response to the whole network synchronous clock trigger signal, the shadow flow table preloaded with the flow table increment is atomically switched to the current flow table. The application utilizes the predictability of the satellite orbit, and through the discrete time slicing and increment compression mechanism, effectively alleviates the routing storm and signaling overhead pressure under the high dynamic topology, and realizes the efficient utilization of the inter-satellite link bandwidth and the smooth transition of the forwarding state.

Description

Technical Field

[0001] This application relates to the field of satellite communication network technology, and more specifically, to a method for updating SDN routes in low-Earth orbit satellite networks based on time-slicing prediction, a method for generating and sending route update packets, a method for receiving and switching satellite routing flow tables, a satellite routing controller, satellite communication nodes, and media. Background Technology

[0002] In a large low-Earth orbit satellite constellation network, satellite nodes are in high-speed motion, causing the link connections between satellites and between satellites and ground stations to change frequently over time. To support the inter-satellite forwarding of massive amounts of data, the network needs to maintain and update global routing information in real time to cope with the dynamic topology environment that changes on a second-by-second basis.

[0003] Existing satellite routing schemes typically employ traditional distributed routing protocols (such as OSPF or BGP). This approach synchronizes the network topology by continuously exchanging Link-State Broadcasts (LSAs) between satellite nodes and recalculates the shortest path upon detecting link connectivity issues. Subsequently, each satellite updates its forwarding table entries based on its local calculations to guide packet flow.

[0004] However, this traditional routing update scheme has significant technical drawbacks in low-Earth orbit satellite scenarios. Due to the extremely drastic topology changes, distributed protocols can induce frequent signaling flooding, leading to severe routing storms and consuming valuable inter-satellite link bandwidth. Simultaneously, route convergence speed often lags behind the topology change rate, easily resulting in routing black holes or loops. Furthermore, if a centralized SDN distribution mode is adopted, real-time transmission of the full flow table would overload the control link, making it difficult to meet the requirements for real-time and smooth switching of forwarding states in highly dynamic environments. Summary of the Invention

[0005] This application provides a time-slicing prediction-based SDN routing update method for low-Earth orbit satellite networks, a routing update packet generation and transmission method, a satellite routing flow table reception and switching method, a satellite routing controller, a satellite communication node, and a medium, to at least alleviate the aforementioned technical problems.

[0006] A time-slicing prediction-based SDN routing update method for low-Earth orbit satellite networks includes: Step 1: The satellite routing controller calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of the satellite nodes in order to generate a time-step partition sequence; Step 2: The satellite routing controller constructs a corresponding full network topology snapshot based on the partition sequence of the time step to generate a global routing flow table; Step 3: The satellite routing controller generates a route update packet based on the global routing flow table; Step 4: The satellite routing controller uploads the routing update packet to the target satellite node in response to the trigger signal generated by the network-wide synchronization clock, controls the shadow flow table preloaded with the flow table increment to atomically switch to the current flow table, and performs data forwarding based on the current flow table.

[0007] Optionally, in step 1, the satellite routing controller calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of the satellite nodes, including: The satellite routing controller performs time-varying analysis of link connectivity based on the orbital dynamics parameters to obtain the topology change rate, which reflects the frequency of increases and decreases in links across the entire network. The satellite routing controller determines the time step of each time slot unit in the partitioned sequence by comparing the topology change rate with a preset change rate threshold.

[0008] Optionally, the satellite routing controller determines the time step of each time slot unit in the partitioned sequence by comparing the topology change rate with a preset change rate threshold, including: If the topological change rate is higher than the preset change rate threshold, then the time step is established as a short period step, and the time slot unit defined by the short period step is injected into the partition sequence; If the topological change rate is lower than the preset change rate threshold, the time step is established as a long period step, and the time slot unit defined by the long period step is injected into the partition sequence.

[0009] Optionally, in step 2, the satellite routing controller constructs a corresponding full-network topology snapshot based on the partition sequence of the time step to generate a global routing flow table, including: For each time slot unit in the partitioned sequence, the satellite routing controller constructs a graph-theoretic topology structure consisting of a set of nodes and a set of links based on the orbital dynamics parameters, serving as a snapshot of the entire network topology; The satellite routing controller uses the Dijkstra algorithm to perform shortest path optimization on the entire network topology snapshot in order to determine the global routing flow table for each of the time slot units.

[0010] Optionally, in step 3, the satellite routing controller generates a route update packet based on the global routing flow table, including: The satellite routing controller performs a differential subtraction operation on two global routing flow tables that are temporally adjacent to each other to extract flow table increments that contain only changes to flow table entries; The satellite routing controller performs incremental encoding compression on the flow table increments using the flow table compression engine to obtain route update packets with reduced signaling volume.

[0011] Optionally, in step 4, before the target satellite node controls the atomic switching of the shadow flow table preloaded with the flow table increment to the current flow table, the following steps are also included: The target satellite node receives the routing update packet via the uplink and performs decompression and data verification on the routing update packet to store the decompressed data in the flow table sequence buffer.

[0012] Optionally, before the target satellite node controls the atomic switching of the shadow flow table preloaded with the flow table increment to the current flow table, it also includes: The target satellite node establishes a dormant shadow flow table through a dual buffer mechanism, and at a preset advance time before the network-wide synchronization clock reaches the time slot unit boundary, it retrieves the corresponding flow table increment from the flow table sequence buffer and injects it into the shadow flow table to complete the preloading of the shadow flow table.

[0013] Optionally, in response to a trigger signal generated by the network-wide synchronization clock, the target satellite node controls the atomic switching of the shadow flow table preloaded with the flow table increment to become the current flow table, including: When the network-wide synchronization clock reaches the time slot unit boundary, the target satellite node performs an atomic switch on the logical mapping relationship between the shadow flow table and the current flow table, so that the original shadow flow table is changed into the current flow table used to guide the data forwarding.

[0014] Optionally, when the satellite routing controller determines the time step size corresponding to each time slot unit in the partitioned sequence: In response to the low topological dynamics caused by the satellite node moving to the polar region, the partitioning sequence is generated using the long period step size; In response to the high topological dynamics generated when the satellite node moves to the mid-latitude intersection region, the partitioning sequence is generated using the short period step size.

[0015] Optionally, the satellite routing controller uploads the routing update packet to the target satellite node, including: When the target satellite node passes through the coverage area of ​​the ground base station, the satellite routing controller uploads the routing update packet containing the future preset time period to the target satellite node for pre-embedded storage via the power supply link.

[0016] This application embodiment also provides a method for generating and sending route update packets, which includes: the ground calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of satellite nodes to generate a time-step partition sequence; the ground constructs a corresponding overall network topology snapshot based on the time-step partition sequence to generate a global routing flow table; the ground generates a route update packet based on the global routing flow table and uploads it to the target satellite node.

[0017] This application embodiment also provides a method for receiving and switching satellite routing flow tables, which includes: a target satellite node receiving a routing update packet uploaded from the ground; the target satellite node responding to a trigger signal generated by a network-wide synchronization clock, controlling a shadow flow table preloaded with flow table increments to atomically switch to the current flow table based on the routing update packet, and performing data forwarding based on the current flow table.

[0018] This application also provides a satellite routing controller, which is deployed on the ground and is used to perform the following steps: calculating the overall network topology evolution trend by acquiring the orbital dynamic parameters of satellite nodes to generate a time-step partition sequence; constructing a corresponding overall network topology snapshot based on the time-step partition sequence to generate a global routing flow table; and generating a routing update packet based on the global routing flow table and uploading it to the target satellite node.

[0019] This application also provides a satellite communication node for performing the following steps: Receive the route update packets uploaded from the ground; In response to the trigger signal generated by the network-wide synchronization clock, the shadow flow table with preloaded flow table increments is atomically switched to the current flow table based on the route update packet, and data forwarding is performed based on the current flow table.

[0020] This application also provides a computer storage medium storing computer-executable instructions thereon, which are executed to implement the methods described in any embodiment of this application.

[0021] The technical advantages of the technical solution provided in this application are: The routing update method in this application addresses the technical shortcomings of traditional schemes, such as routing storms induced by distributed protocols in highly dynamic topologies and the huge signaling overhead caused by full SDN distribution. By calculating the orbital dynamic parameters of satellite nodes and generating a partition sequence containing time steps, it alleviates the dependence of routing updates on real-time link state detection. Compared with the traditional real-time broadcast LSA method, this application utilizes the predictability of orbits to pre-generate partition sequences, enabling the entire network to perform predictive maintenance based on a defined time step. This avoids the blind flooding of routing signaling from a physical source and effectively alleviates the pressure on inter-satellite link bandwidth.

[0022] By performing differential processing and compressing the generated global routing flow table to produce route update packets, this approach alleviates the technical bottleneck of limited control link capacity. Compared to the traditional method of distributing all flow table entries, this application extracts only the flow table increments for compressed transmission, significantly reducing the amount of signaling data during the update process. This approach enables low-bandwidth feeder links to better support the distribution of large-scale flow table rules, improving the transmission efficiency and success rate of control signaling.

[0023] By preloading shadow flow tables and using atomic switching based on a synchronous clock, a satellite-ground collaborative synchronous update mechanism is formed, which at least alleviates the problems of slow route convergence and unstable forwarding status during switching in traditional methods. Compared with the routing black hole phenomenon caused by traditional hop-by-hop handshakes or asynchronous updates, this application uses a network-wide synchronous clock to perform pointer swapping at time slot boundaries, achieving instantaneous and smooth switching of flow table entries. This approach ensures that satellite nodes have accurate forwarding information the moment topology changes, significantly improving the forwarding stability of satellite networks in highly dynamic environments. Attached Figure Description

[0024] Figure 1 This is a flowchart of a low-Earth orbit satellite network SDN routing update method based on time-slicing prediction, according to an embodiment of this application. Figure 2 This is a schematic diagram of a time-slicing prediction-based SDN routing update system for low-Earth orbit satellite networks, as described in an embodiment of this application. Detailed Implementation

[0025] like Figure 1 The image shows an embodiment of the present application of a low-Earth orbit satellite network (SDN) routing update method based on time-slicing prediction, comprising: Step 1: The satellite routing controller calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of the satellite nodes in order to generate a time-step partition sequence; Step 2: The satellite routing controller constructs a corresponding full network topology snapshot based on the partition sequence of the time step to generate a global routing flow table; Step 3: The satellite routing controller generates a route update packet based on the global routing flow table; Step 4: The satellite routing controller uploads the routing update packet to the target satellite node in response to the trigger signal generated by the network-wide synchronization clock, controls the shadow flow table preloaded with the flow table increment to atomically switch to the current flow table, and performs data forwarding based on the current flow table.

[0026] Optionally, in step 1, the satellite routing controller calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of the satellite nodes, including: the satellite routing controller performs time-varying analysis of link connectivity based on the orbital dynamic parameters to obtain the topology change rate reflecting the frequency of link increases and decreases in the entire network; the satellite routing controller determines the time step of each time slot unit in the partitioned sequence by comparing the topology change rate with a preset change rate threshold.

[0027] In the specific implementation process, the satellite routing controller acquires the orbital dynamic parameters of satellite nodes through the feed link or network interface. These parameters include the instantaneous position coordinates of the satellite in the inertial coordinate system, its velocity vector, and time reference information. Using these parameters, combined with preset constellation configuration rules, the satellite routing controller performs predictive calculations on the spatial motion trajectory of each satellite node. This transforms physical orbital data into a spatiotemporal coordinate stream with network attributes, laying the data foundation for subsequent analysis of the dynamic stability of the topology. Due to the highly predictable motion of low-Earth orbit satellite constellations, this input based on physical characteristics establishes the predictability of the entire network's connectivity status in the time dimension.

[0028] Preferably, in the specific solution implementation, the satellite routing controller performs time-varying analysis of inter-satellite link connectivity based on the satellite node position information stream obtained above. In this step, the satellite routing controller calculates the geometric distance between adjacent satellite nodes of the target in real time and compares it with the communication distance threshold value in the configuration memory. When it is identified that the distance between two satellite nodes is within the threshold range and is not obstructed by geophysical data, the satellite routing controller establishes the corresponding link connection record at the logical level. By performing a time-series traversal of all potential connection pairs across the entire constellation, the satellite routing controller constructs a dynamic connection topology graph that continuously changes with the time axis. This analysis maps the physical displacement of the satellites to the switching state transformation of the edge set in the network topology, thus providing a logically semantic topology template for quantitatively evaluating the evolution trend of the entire network topology.

[0029] Preferably, the satellite routing controller performs link change frequency analysis on the aforementioned dynamic connection topology map to calculate the topology change rate, which reflects the frequency of link additions and subtractions across the entire network. Specifically, the satellite routing controller establishes a numerical component reflecting the drastic evolution of the topology configuration by statistically summing the number of newly added links and the number of failed links in the link set within a unit observation period. This topology change rate essentially corresponds to the derivative characteristics of the topology map's evolution over time, clearly revealing the changing patterns of connectivity relationships caused by satellites operating in different geographical regions (such as polar or mid-latitude areas). Through continuous tracking of this numerical characteristic, the satellite routing controller achieves a refined characterization of the overall network topology evolution trend, providing crucial feature basis for subsequent differentiated slicing decisions.

[0030] Preferably, the satellite routing controller performs a value discrimination mapping between the calculated topology change rate and a pre-set change rate threshold. The purpose of this discrimination logic is to identify the stable and active periods of the network configuration, thereby achieving a balance between signaling overhead and routing accuracy. When the satellite routing controller detects that the current topology change rate is higher than the change rate threshold, it determines that the entire network is in a highly dynamic evolution state, and thus establishes the time step of the current processing period as a short-cycle step. If the topology change rate is lower than the change rate threshold, it determines that the network is in a relatively stable state, and establishes the time step as a long-cycle step. This change rate-driven decision-making mechanism ensures that the time granularity of the analysis can be dynamically adjusted according to the actual steepness of the topology change, mitigating the resource waste caused by redundant computation.

[0031] Preferably, in one scenario, the satellite routing controller utilizes the established long-period or short-period step size to perform variable-length slice encapsulation processing for continuous future prediction periods. In specific processing actions, the satellite routing controller performs non-equidistant discretization cutting of the continuous time axis according to the selected time step, thereby generating a series of time slot units defined by start and end times. Each time slot unit is logically assigned an ordered sequence number and associated with its corresponding duration parameter. This implementation of variable-length slicing allows the sampling points of routing information to adaptively align to moments of drastic topology changes, while reducing redundant entries during stable periods by extending the duration. By organizing multiple heterogeneous duration segments in an orderly manner, the satellite routing controller initially constructs a time framework describing future topology evolution, providing a structured unit carrier for the final generation of time step division sequences.

[0032] Preferably, the satellite routing controller aggregates the generated time slot units and performs logical orchestration according to the temporal evolution relationship, thereby ultimately generating a time step partitioning sequence. The generated time step partitioning sequence is presented in the memory image as a partitioning dictionary with an ordered index, completely recording the fragment nodes of the entire network topology within the future prediction timeframe. This sequence serves as the logical foundation of the entire routing update process, facilitating the sampling frequency and calculation cycle of subsequent network topology snapshots. By generating this dynamically generated sequence based on the network topology evolution trend, the satellite routing controller achieves an essential transformation from physical orbit prediction to network orchestration logic. The obtained time step partitioning sequence is then passed to the subsequent snapshot construction stage as the core instruction basis for establishing the static topology calculation time point, ensuring that the subsequently generated global routing flow table can achieve the highest forwarding state consistency with minimal storage cost.

[0033] Optionally, the satellite routing controller determines the time step size of each time slot unit in the partitioned sequence by comparing the topology change rate with a preset change rate threshold. This includes: if the topology change rate is higher than the preset change rate threshold, the time step size is determined as a short-period step size, and the time slot units defined by the short-period step size are injected into the partitioned sequence; if the topology change rate is lower than the preset change rate threshold, the time step size is determined as a long-period step size, and the time slot units defined by the long-period step size are injected into the partitioned sequence.

[0034] Preferably, the satellite routing controller retrieves the orbital dynamic parameters corresponding to each satellite node participating in the network through a communication link. These orbital dynamic parameters include the satellite's instantaneous spatial coordinates in a preset inertial coordinate system, its velocity components, and high-precision reference time information. Using these parameters and a pre-set constellation orbital model, the satellite routing controller performs predictive simulations of the future spatial trajectories of each satellite node. This action transforms macroscopic physical orbital motion into microscopic network node position displacement flow, providing deterministic physical quantity input for subsequent analysis of the dynamic stability of the topology. Since the motion of low-Earth orbit satellites is strictly constrained by celestial mechanics, this input method based on orbital dynamic parameters establishes the computability of the entire network topology within the future prediction period, mitigating the topology perception lag caused by real-time detection delays.

[0035] Preferably, the satellite routing controller performs time-varying analysis on inter-satellite link connectivity based on the spatial trajectory displacement flow of each satellite node obtained above. In the specific processing, the satellite routing controller calculates the geometric distance between two potentially adjacent satellite nodes and retrieves a communication distance threshold pre-stored in the configuration memory. Subsequently, the satellite routing controller performs a value discrimination mapping between the calculated geometric distance and the communication distance threshold. When it is identified that the geometric distance is within the threshold and not subject to geophysical obstruction, a corresponding link connection record is established at the logical level. By performing time-series traversal processing on all potential node pairs in the entire network, the satellite routing controller constructs a network topology model that dynamically evolves over time. The establishment of this model realizes the mapping from satellite physical displacement to network logical connection states, laying a logical foundation for quantitatively evaluating the frequency of network configuration changes.

[0036] Preferably, the satellite routing controller performs link change frequency analysis on the constructed network topology model to calculate the topology change rate, which reflects the frequency of link additions and subtractions across the network. In the specific calculation, the satellite routing controller calculates the sum of algebraic changes in the number of newly added and failed connection entries within the selected observation window, thereby establishing a numerical feature component reflecting the drastic evolution of the topology configuration. The generated topology change rate essentially describes the gradient properties of the network topology model over time, revealing the fluctuation patterns of connectivity caused by satellites operating in mid-latitude crossover zones or polar regions. By extracting this numerical feature component in real time, the satellite routing controller achieves a quantitative characterization of the network topology evolution trend, providing core feature basis for subsequent refined slicing decisions and ensuring the adaptation of the partitioning logic to the dynamic nature of the topology as much as possible.

[0037] Preferably, the satellite routing controller obtains the topology change rate, which reflects the overall network topology evolution trend, obtained from the above calculation, and performs a value discrimination mapping with a preset change rate threshold pre-configured in non-volatile memory. The purpose of this discrimination step is to identify different dynamic sensitive intervals in the satellite network topology evolution, thereby establishing the analysis granularity that best suits the current topology environment. When the satellite routing controller detects that the current topology change rate is higher than the preset change rate threshold, it determines that the network is in a high dynamic sensitive interval; if it detects that the topology change rate is lower than the preset change rate threshold, it determines that the network is in a low dynamic stable interval. This feature-feedback-based discrimination logic enables targeted decision support for subsequently establishing a reasonable time step based on the actual steepness of the topology change, thereby at least alleviating the technical bottleneck of traditional methods where fixed sampling steps cannot balance update accuracy and computational overhead.

[0038] Preferably, the satellite routing controller performs variable-length slice decisions for the future prediction period based on the above discrimination results to establish the time step size used to generate the segmented sequence. Specifically, if the discrimination results point to a highly dynamic and sensitive region, the satellite routing controller establishes a short-period time step size; if the discrimination results point to a low-dynamic and stable region, the time step size is established as a long-period time step size. This flexible variable-length slice decision method ensures that link state changes can be captured at a high frequency during periods of drastic topology changes, while suppressing the generation of redundant flow table update entries during periods of topology stability by expanding the time step size. The established time step size (whether short-period or long-period) is pushed to the sequence organization module in real time. This processing action enables dynamic allocation of computing resources within the prediction period and establishes the non-uniformly spaced distribution characteristics of the routing update sequence in the time domain.

[0039] Preferably, the satellite routing controller uses the established time steps to perform discretization processing on the continuous time axis, thereby generating a series of time slot units defined by start and end times. Each time slot unit physically corresponds to a quasi-static maintenance phase of the entire network topology. The satellite routing controller logically arranges and indexes the generated multiple time slot units according to the temporal evolution relationship, ultimately generating a time step partitioning sequence reflecting the topology fragmentation structure in future time periods. The generated time step partitioning sequence is presented in the memory image as a discretized time coordinate system with temporal index. This sequence serves as the logical foundation of the entire routing update process, providing a precise time triggering benchmark for subsequently constructing the network topology snapshot corresponding to each time slot. This at least alleviates the technical problem of bandwidth waste caused by blind flooding of routing update signaling in the high-dynamic environment of low-Earth orbit satellites, resulting in highly timely and adaptable update packets.

[0040] Optionally, in step 2, the satellite routing controller constructs a corresponding full-network topology snapshot based on the time-step partitioning sequence to generate a global routing flow table, including: for each time slot unit in the partitioning sequence, the satellite routing controller constructs a graph theory topology structure composed of a set of nodes and a set of links based on the orbital dynamics parameters, as a full-network topology snapshot; the satellite routing controller uses the Dijkstra algorithm to perform shortest path optimization processing on the full-network topology snapshot to determine the global routing flow table corresponding to each time slot unit.

[0041] Preferably, the satellite routing controller retrieves the time step division sequence generated by the preceding steps and extracts the various time slot units constituting the future prediction period. For each time slot unit, the satellite routing controller, through its internal dynamics deduction module, performs spatial position prediction for each satellite node in conjunction with synchronously acquired orbital dynamics parameters. In the specific processing action, the satellite routing controller calculates the three-dimensional spatial coordinates of the target satellite at the start time of the selected time slot unit based on physical roots such as the orbital semi-major axis, eccentricity, and inclination angle contained in the orbital dynamics parameters, thereby establishing the physical benchmark describing the static nodes of the network. This processing step utilizes the strong determinism of satellite operation to discretize the dynamic time axis into a series of definite spatial position nodes, providing accurate coordinate input for the subsequent construction of a graph theory model of the entire network topology. By strongly temporally associating the position deduction with the time slot units, it ensures that each generated topology graph has extremely high physical self-consistency.

[0042] Preferably, after acquiring the spatial locations of each satellite node, the satellite routing controller performs a full-network node mapping process to generate a logical-level node set. Subsequently, the satellite routing controller performs link connectivity determination on the node set to determine which node pairs have the physical conditions to establish inter-satellite links. During this determination, the satellite routing controller calculates the geometric Euclidean distance between two satellite nodes and compares it with a radio line-of-sight threshold in the configuration memory. When it is identified that the distance between two nodes is less than the threshold and the line-of-sight path between them is not obstructed by the Earth's surface, the satellite routing controller establishes an edge with a defined weight at the logical level. By performing the above traversal determination on all potential connection pairs in the node set, the satellite routing controller finally generates a link set consisting of all available logical edges. This process realizes the transformation from spatial coordinate distribution to network logical connection relationships, providing complete edge information for constructing the graph theory structure of the entire network topology.

[0043] Preferably, the satellite routing controller aggregates the generated node and link sets and maps them to a graph theory data model to construct a snapshot of the entire network topology corresponding to the current time slot unit. The generated snapshot is stored in memory as a weighted adjacency matrix or adjacency list, where the elements at the intersections of rows and columns represent the real-time connection state and communication cost between two satellite nodes. This generated snapshot represents, at a technical level, the quasi-static physical configuration of the network within a specific time window, and is the only valid input for subsequent routing calculations. Through this construction, the satellite routing controller captures the highly dynamically evolving constellation network as a series of discrete static graph structures, thereby at least mitigating the problem of indescribable connection states caused by highly dynamic environments. Each snapshot is assigned a unique index number consistent with its corresponding time slot unit, ensuring the traceability of the topology state during time-domain evolution.

[0044] Preferably, for the network-wide topology snapshot generated above, the satellite routing controller invokes its built-in routing calculation module to perform shortest path optimization processing based on the Dijkstra algorithm. In the specific solution logic, the satellite routing controller uses the adjacency relationships in the network-wide topology snapshot as the path space for pathfinding, and uses link delay or hop count as the optimization target weight. By performing iterative relaxation operations in the network-wide topology snapshot, the satellite routing controller searches for the optimal path tree to all other destination nodes for each source node in the network. This processing action actually uses discrete mathematics to extract the logical subset with the highest forwarding efficiency from the complex connection graph. This path optimization result obtained through the Dijkstra algorithm mathematically guarantees that, under the static topology environment defined by the current time slot unit, all network data packets can migrate along the path with the fewest physical hops or the least delay, thereby providing path-level decision support for generating high-quality routing instructions.

[0045] Preferably, based on the path optimization results obtained above, the satellite routing controller performs route entry transformation processing to generate the global routing flow table. Specifically, the satellite routing controller extracts the next-hop exit parameters corresponding to each node in the optimal path tree and performs mapping and encapsulation with the target address prefix, thereby generating flow table matching items and execution action items that conform to the SDN southbound interface protocol definition. Subsequently, the satellite routing controller summarizes the forwarding rules of all satellite nodes in the entire network at the current moment, thereby finally determining the global routing flow table corresponding to each time slot unit. The generated global routing flow table is logically presented as a set of many-to-one route lookup tables, which defines the standard guidance logic of the entire network data forwarding plane in the current spatiotemporal state. This generation step marks the leap from graph theory model to specific network forwarding instructions. The determined global routing flow table is pushed to the differential comparison queue in real time as a key reference for subsequent calculation of flow table increments, reflecting the deep follow-up of routing decisions on the topology snapshot state.

[0046] Preferably, to ensure the consistency of the generated global routing flow table across regions, the satellite routing controller performs a network-wide connectivity consistency verification on the generated global routing flow tables. Since the time step division sequence includes variable-length time slots, the satellite routing controller dynamically adjusts the routing weight parameters based on the topological stability characteristics under different time steps. When a time slot unit is identified as crossing a highly dynamic region such as a polar crossroads, the satellite routing controller guides the path to avoid vulnerable links by increasing the weight penalty factor, thereby optimizing the robustness of the generated global routing flow table during dynamic switching. This series of progressive processing actions ensures that the final generated global routing flow table is not only mathematically optimal but also highly reliable at the physical execution level. This complete link from the division sequence to the flow table generation establishes a digital foundation for time-sliced ​​routing updates, providing satellite nodes with highly deterministic routing prior knowledge for autonomous updates in scenarios without frequent handshake interactions, at least alleviating the technical pain point of lag in routing convergence in low-Earth orbit satellite networks.

[0047] Optionally, in step 3, the satellite routing controller generates a route update packet based on the global routing flow table, including: the satellite routing controller performs a differential subtraction operation on two global routing flow tables that are temporally adjacent to each other to extract the flow table increment containing only the flow table entry change information; the satellite routing controller performs incremental encoding compression processing on the flow table increment through the flow table compression engine to obtain a route update packet with reduced signaling volume.

[0048] In the specific implementation process, the satellite routing controller retrieves the global routing flow tables generated for each corresponding time slot unit from its routing configuration database. Since these flow tables are a sequence set generated according to temporal evolution relationships, the satellite routing controller, through its internal data scheduling module, extracts two global routing flow tables that are adjacent within the prediction period (i.e., the set of forwarding rules between the current time slot to be processed and the immediately preceding time slot). To this end, a time-domain difference comparison window is established, providing the original logical input for subsequent identification of link switching and forwarding path changes caused by satellite motion. This extraction of data from adjacent time periods ensures that subsequent differential operations always apply to a forwarding instruction set with temporal continuity, avoiding the computational overhead of invalid data.

[0049] Preferably, the satellite routing controller performs a differential subtraction operation on the two globally adjacent routing flow tables extracted above. In the specific calculation logic, the satellite routing controller uses the flow table at the later time step as the minuend and the flow table at the previous time step as the subtraction reference, performing a line-by-line comparison of the flow table entry matching field and action field. If a logical change is detected in the execution action of a routing rule between the two time steps (such as the next hop exit identifier), or if a new routing prefix that did not exist in the previous time step is detected, these changes are extracted and mapped into a set of incremental entries. This differential subtraction operation achieves a physical separation from full forwarding rules to dynamic variable features, effectively filtering out redundant link information that maintains stability in the constellation network, thereby accurately calculating the flow table increment reflecting the changes in flow table entries.

[0050] Preferably, the generated flow table increments are written to the differentiated cache of the satellite routing controller in real time. Logically, the flow table increments consist of three types of atomic update instructions: adding flow table entries, deleting flow table entries, and modifying flow table entries. Each instruction entry is associated with a unique physical identifier of the corresponding satellite node. This processing step constructs a "minimum patch set" that reflects the dynamic evolution of the routing policy, eliminating the need for redundant background network state information. The resulting flow table increments not only significantly compress the size of the original routing information in terms of data dimensions but also provide high-purity change material for subsequent targeted signaling encapsulation, ensuring that routing update actions are accurately anchored to the changed link nodes.

[0051] Preferably, the satellite routing controller drives its internally integrated flow table compression engine to perform loading and field analysis processing on the flow table increments stored in the differentiated buffer. The flow table compression engine performs pattern recognition mapping on frequently repeated fields (such as identical execution actions or similar mask prefixes) in the flow table increments. In this step, the satellite routing controller establishes a dictionary-index-based preprocessing method through the flow table compression engine to transform the lengthy original routing string representation into short and fixed-length logical labels. This action achieves an essential transformation from an information redundancy state to an information compact state, resulting in flow table increments participating in subsequent compression actions having higher information entropy, thus providing data preparation for further reducing signaling volume.

[0052] Preferably, the satellite routing controller utilizes the flow table compression engine to perform incremental coding compression processing on the preprocessed data stream. In the specific processing implementation, differential coding logic combined with a probability distribution model is used to perform extreme compression processing on the bit stream reflecting topology changes in the flow table increment. This processing action leverages the regularity of low-Earth orbit satellite topology changes to highly aggregate and simplify update instructions with spatiotemporal correlations, ultimately resulting in a route update packet with reduced signaling volume. By performing this incremental coding compression processing, large-scale flow table change information is successfully compressed within the bandwidth threshold that the feeder link can withstand, at least alleviating the mismatch between the control link capacity and the flow table update requirements in the satellite network.

[0053] Preferably, after completing the compression process, the satellite routing controller generates a routing update packet containing multiple sets of incremental instructions. The generated routing update packet is assigned an execution time stamp corresponding to the target time slot unit and encapsulated into a data frame structure with a deterministic length. Technically, this generated routing update packet represents a highly streamlined onboard routing patch, enabling predictive control and precise reach of the inter-satellite link status from the ground. The determined routing update packet is then pushed to the communication front-end, ready to be uploaded to each satellite node via the uplink. This conversion link from the full flow table to the compressed incremental packet ensures that the routing update process can achieve network-wide status synchronization with extremely low signaling costs.

[0054] Optionally, in step 4, before the target satellite node controls the atomic switching of the shadow flow table preloaded with the flow table increment to the current flow table, the following steps are also included: the target satellite node receives the routing update packet through the uplink and performs decompression and data verification on the routing update packet to store the decompressed data in the flow table sequence buffer.

[0055] Preferably, during the preparation phase for distributing routing information, the satellite routing controller fully loads the global routing flow tables corresponding to each time slot unit in the partitioning sequence from the routing management module. Since the topology of the low-Earth orbit satellite network evolves continuously over time, the satellite routing controller automatically identifies and extracts two globally adjacent global routing flow tables in the time domain through internal timing comparison logic (e.g., establishing the flow table at the current prediction time as the minuend and the flow table at the previous prediction time as the minuend reference). To this end, a dynamic reference benchmark is established, enabling the identification of logical variables arising from topology changes from the full set of network forwarding instructions. By aligning the two selected global routing flow tables, the satellite routing controller provides spatiotemporally consistent raw data pairs for subsequent differential operations. This step ensures that the subsequently generated update instructions accurately reflect the evolution trend of network connection status, avoiding unnecessary bandwidth consumption caused by the transmission of the full flow table.

[0056] Preferably, the satellite routing controller performs a differential subtraction operation on the two global routing flow tables that are temporally adjacent. During the actual computational execution, the satellite routing controller traverses all routing entries in the flow table at the next time step and performs a field-level comparison with entries in the flow table at the previous time step that have the same target network prefix. If a change in the next-hop exit identifier in a routing rule is detected, or if a new routing prefix not covered in the previous time step is detected, the satellite routing controller extracts these changed fields and maps them to a set of differentiated patch instructions. This differential subtraction operation physically separates the full routing state from dynamic variable features, thereby calculating the flow table increment that only includes changes to flow table entries. The generated flow table increment logically only covers the set of instructions that require physical modification by the satellite nodes, significantly compressing the scale of the original routing description.

[0057] Preferably, after obtaining the generated flow table increments, the satellite routing controller drives its internally integrated flow table compression engine to perform structured preprocessing on the increment data. The flow table compression engine performs pattern recognition on repeated fields, wildcard masks, and similar port actions contained in the flow table increments, mapping the lengthy original routing strings into index labels of fixed length. This action achieves a fundamental transformation from an information-redundant state to a compact feature state, resulting in flow table increments participating in subsequent compression stages having higher information entropy. Based on this, the flow table compression engine utilizes the temporal correlation characteristics in the flow table increments to perform topology feature encoding on each change instruction. This step, through the logical processing of the flow table compression engine, pre-eliminates statistical redundancy in the instruction stream, providing data preparation for the efficient migration of routing information on low-bandwidth feeder links.

[0058] Preferably, the satellite routing controller performs incremental coding compression on the preprocessed data through the flow table compression engine. In the specific processing implementation, a differential coding-based mapping logic is used to perform maximum bit-width compression on the bit stream in the flow table increment, further reducing the signaling volume. This processing leverages the localization characteristic of routing entry changes caused by the strong regularity of satellite orbital operation, highly aggregating scattered change instructions into data packets with extremely small volumes. By performing this incremental coding compression, the satellite routing controller ultimately generates a routing update packet containing change information for multiple predicted future time periods. The generated routing update packet not only meets the transmission requirements of the constrained link in terms of volume but is also assigned a target addressing label matching the identity of the target satellite node. The determined routing update packet is then pushed to the communication link layer, ready to be uploaded to the target satellite node via the uplink, thereby achieving predictive maintenance and precise routing control of the onboard forwarding plane from the ground side without relying on frequent inter-satellite handshakes.

[0059] Optionally, before the target satellite node controls the atomic switching of the shadow flow table preloaded with the flow table increment to the current flow table, the method further includes: the target satellite node establishing a dormant shadow flow table through a dual buffer mechanism, and retrieving the corresponding flow table increment from the flow table sequence buffer and injecting it into the shadow flow table at a preset advance time before the network synchronization clock reaches the time slot unit boundary, so as to complete the preloading of the shadow flow table.

[0060] Preferably, in the preparation phase before performing the atomic handover, the target satellite node uses its built-in radio frequency communication component to perform signal acquisition and down-conversion processing on the wireless signals sent by the satellite routing controller. During this phase, the target satellite node monitors the real-time status of the uplink using a preset communication frequency band. Upon identifying a valid guiding sequence, it automatically opens the data reception window. The target satellite node continuously receives baseband signal streams containing multiple sets of topology prediction information through the uplink and performs physical layer decoding processing to obtain compressed and encapsulated routing update packets. This reception action establishes a cross-space signaling migration channel, enabling the successful migration of routing prior knowledge generated on the ground to the onboard computing environment, providing the original data input for subsequent flow table updates performed locally on the satellite.

[0061] Preferably, the target satellite node retrieves the received routing update packet through its internal logic processing unit and performs decompression and restoration processing on it. Since the routing update packet undergoes extreme compression based on a flow table compression engine on the ground side, its internal data exists in a compact differential encoding form. The target satellite node calls a preset decompression operator to perform bit-width expansion and field mapping on the bit stream within the packet. This processing action restores the highly redundant compressed signaling data to the original command stream with network forwarding semantics, thereby determining the decompressed data reflecting the details of routing changes. The generated decompressed data is temporarily stored in a high-speed register on the satellite's local machine. By performing this decompression and restoration processing, while ensuring extremely low signaling overhead in the feeder link, it ensures that the satellite node can obtain complete and logically readable routing change rules.

[0062] Preferably, the target satellite node performs data verification processing on the decompressed data to ensure the integrity and accuracy of control signaling during space transmission. During this process, the target satellite node extracts the cyclic redundancy check bit carried in the decompressed data and performs logical discrimination mapping with the fingerprint features calculated in real-time by the local computing unit for the valid data area. When the feature values ​​of the two are found to match perfectly, it is determined that the routing update information has not been tampered with by satellite-to-ground link noise, and thus, verified flow table data is generated. This step serves as a quality control anchor point for the routing update process, effectively avoiding the negative impact of bit errors caused by the harsh space electromagnetic environment on the forwarding plane.

[0063] Preferably, the target satellite node acquires the validated flow table data generated above and writes it into the flow table sequence cache defined in the physical memory using its configured storage controller. During the specific storage execution process, the target satellite node performs ordered arrangement and cataloging of the validated flow table data according to the predicted time slot index corresponding to each routing rule, thereby generating a cached flow table increment sequence with time-dimensional lookup capabilities. This processing step establishes a "policy preparation pool" located before the physical forwarding plane, achieving logical decoupling between "immediate receipt and storage" and "on-demand retrieval" of routing signaling. The cached flow table increment sequence stored in the flow table sequence cache covers all topology change patches within a preset future timeframe, providing complete logical support for the satellite to perform autonomous routing maintenance after leaving the ground station's coverage area.

[0064] Preferably, the target satellite node uses its real-time monitoring circuit to poll the local count value generated by the network-wide synchronization clock to establish the trigger point for the preloading action. When the value of the network-wide synchronization clock evolves to a preset lead time (e.g., 500 milliseconds before the flow table takes effect), the target satellite node automatically generates an asynchronous scheduling command. This processing action utilizes a nanosecond-level synchronization clock as a metronome, leaving necessary computational margin for the loading process of forwarding rules. By capturing the preset lead time, it ensures that even under high onboard processor load, the preparation work for the shadow flow table can be completed before the forwarding switch occurs, thereby avoiding packet loss due to loading delays and enabling the update process to move dynamically on the time scale.

[0065] Preferably, in response to the aforementioned generated scheduling command, the target satellite node drives the data migration unit to extract the selected cached flow table increment sequence from the flow table sequence buffer. Subsequently, the target satellite node injects the extracted data stream into the shadow flow table in a standby state, performing overwrite and insertion operations on flow table entries, thereby completing the preloading of the shadow flow table. This processing step utilizes a double buffer mechanism to construct a forwarding logic master template reflecting the topology configuration of the next time slot in the background without interfering with the current data forwarding. The generated shadow flow table, preloaded with the flow table increments, is physically ready and only needs to wait for the final trigger signal to switch instantly. This collaborative processing method, which retrieves data from the flow table sequence buffer in advance and fills the shadow flow table, establishes the atomicity of route updates, supporting smooth evolution and zero-interruption switching of forwarding states in a highly dynamic satellite network environment.

[0066] Optionally, in response to a trigger signal generated by the network-wide synchronization clock, the target satellite node controls the atomic switching of the shadow flow table preloaded with the flow table increment to become the current flow table. This includes: when the network-wide synchronization clock reaches the time slot unit boundary, the target satellite node performs an atomic switch of the logical mapping relationship between the shadow flow table and the current flow table, so that the original shadow flow table is changed into the current flow table used to guide the data forwarding. In one scenario, performing the atomic switch of the logical mapping relationship is, for example, an atomic switch of a storage pointer swap operation. In another scenario, in an FPGA- or ASIC-based embodiment, performing the atomic switch of the logical mapping relationship is, for example, achieving the atomic switch of the flow table by toggling a status register or switching a storage bank selection signal.

[0067] Preferably, the target satellite node utilizes its built-in high-precision timing circuitry to perform uninterrupted phase tracking of the network-wide synchronization clock maintained through the constellation's synchronization links. During this process, the target satellite node extracts the absolute time value output by the network-wide synchronization clock and performs a logical comparison with a pre-received sequence containing time steps from the ground side. This processing maps the abstract system beat to the physical forwarding timing, ensuring that the onboard side can accurately perceive the precise nodes undergoing time-domain evolution in real time. Through this continuous polling comparison, a timeline reference reflecting the topology's lifespan is established, providing a deterministic time basis for identifying the starting point of the next routing cycle and ensuring that all network nodes can operate synchronously under a unified logical pulse.

[0068] Preferably, when the value of the network-wide synchronization clock evolves to the termination time corresponding to the currently effective time slot unit, the target satellite node identifies the time slot unit boundary. In this step, the onboard control logic captures the timestamp flip and performs an overlap determination with the starting point of the next time step recorded in the partition sequence. This action achieves physical anchoring of the discrete time-domain segment points, marking the end of the previous stage's static topology state, while the next stage's topology configuration predicted by the ground side immediately enters its countdown to effectiveness. The technical advantage of identifying the time slot unit boundary is that it establishes absolute trigger coordinates for subsequent atomic actions, eliminating time alignment deviations caused by asynchronous discovery of link changes in traditional distributed protocols.

[0069] Preferably, in response to the identified time slot unit boundary, the clock-driven logic inside the target satellite node instantaneously generates a high-priority system interrupt signal as a trigger signal generated by the network-wide synchronization clock. Subsequently, the target satellite node retrieves and responds to this trigger signal, immediately blocking modification permissions for existing forwarding table entries and initiating an atomic switching instruction for the shadow flow table. Since the shadow flow table has already pre-completed the loading process for the selected flow table increment at this time, its internal data structure fully reflects the forwarding rules under the new time slot. This step utilizes the synchronously generated physical signal as a logical gate, establishing the execution rhythm of the routing strategy's instantaneous transition from the old state to the new state, ensuring that the switching process is completed within a very short time window.

[0070] Preferably, in the specific technical implementation of atomic switching, the target satellite node drives its internal storage control unit to perform an atomic switch of the logical mapping relationship between the shadow flow table and the physical address corresponding to the current flow table. At the specific storage management level, instead of performing actual data migration on the massive flow table entries, the base address pointer in the memory mapping table is modified to instantly map the logical handle originally pointing to the current flow table to the starting address of the shadow flow table, which has been pre-loaded with the flow table increment. This processing action utilizes the indirect addressing characteristics of software-defined networks to achieve logical replacement of massive forwarding table entries through address flipping with minimal displacement. Performing this atomic switch of the logical mapping relationship ensures that the routing update action has an atomic and indivisible characteristic, avoiding unstable states where rules take effect inconsistently during the switching process.

[0071] Preferably, with the successful completion of the atomic switching of the execution logic mapping relationship, the shadow flow table, which was originally in a background standby state, is logically activated, thus officially becoming the new current flow table used to guide subsequent data flow. Simultaneously, the original current flow table (i.e., the expired old flow table) is marked as offline and reverts to a new shadow buffer. This processing action achieves physical recycling of the onboard forwarding table space and ensures that the new rule set takes effect on the entire network data flow instantly. The data set after being changed to the current flow table, because it encapsulates the path optimization results calculated for the new topology configuration, can immediately perform precise packet routing decisions based on the connectivity status of the current physical links, thereby maintaining a high degree of continuity in the logical connectivity of the satellite network even during drastic topology changes.

[0072] Preferably, after establishing a new current flow table, the target satellite node immediately drives the forwarding plane component to perform data forwarding for the input data packets based on the next-hop match entries contained in the current flow table. During this process, each arriving service data packet is matched with an exit port according to the new mapping logic, thus guiding it to the optimal path pre-calculated by the ground side. Since the handover action is completed instantaneously at the time slot unit boundary without intermediate protocol handshake overhead, all satellite nodes in the network achieve synchronous evolution of routing states under the constraint of spatiotemporal consistency. This atomic handover-based processing method at least alleviates the problem of slow routing convergence in the high-dynamic environment of low-Earth orbit satellites, enabling data packets to always migrate along paths with topology prediction, ensuring the forwarding stability and low latency characteristics of large-scale inter-satellite service flow transmission.

[0073] Optionally, when the satellite routing controller establishes the time step size for each time slot unit in the partition sequence: in response to the low topological dynamics generated when the satellite node moves to the polar region, the partition sequence is generated using the long period step size; in response to the high topological dynamics generated when the satellite node moves to the mid-latitude cross region, the partition sequence is generated using the short period step size.

[0074] Preferably, the satellite routing controller retrieves the real-time orbital operating parameters of each satellite node via the feed link and performs a time-domain evolution analysis of the inter-satellite link connectivity of the entire network based on a preset constellation dynamics model. In specific processing, the satellite routing controller calculates the total number of newly added and failed links in the logical connectivity of the entire network within a unit observation period, thereby extracting the topology change rate, which reflects the frequency of link increases and decreases across the entire network. This calculation achieves the acquisition of the derivative characteristics of the network configuration evolving over time, enabling a quantitative perception of the dynamic activity level of the topology. By establishing the topology change rate, the satellite routing controller provides physically semantic feature inputs for subsequent differentiated slicing decisions, ensuring that the time slicing granularity accurately adapts to the current constellation's motion status.

[0075] Preferably, the satellite routing controller retrieves a preset rate of change threshold stored in the configuration memory and compares it with the previously calculated topology change rate. This discrimination logic aims to divide continuous time intervals into topology stability intervals with different stability attributes by filtering the values ​​of dynamic characteristics. When the current topology change rate is detected to be in a low value range and below the preset rate of change threshold, the satellite routing controller determines that the network is in a quasi-static stage; conversely, if the topology change rate is detected to surge and exceed the threshold, the network is determined to have entered a high-dynamic jump stage. This threshold-driven classification and discrimination achieves logical dimensionality reduction of complex topology evolution processes, providing a deterministic decision guide for finally determining the time step of each time slot unit.

[0076] Preferably, in response to the low topological dynamics generated when satellite nodes move to the Earth's polar regions, the satellite routing controller performs parameter mapping processing for the stable state. In polar regions, due to the convergence characteristics of satellite orbits, the relative displacement between satellites changes relatively gradually, resulting in a consistently low calculated topological change rate. Upon recognizing this physical situation, the satellite routing controller automatically establishes a long-period step size for the current processing period (e.g., selecting sixty seconds as the discrete segmentation interval). This processing action effectively reduces the number of redundant snapshot constructions during topological stability by extending the coverage of individual time slot units. Using the long-period step size to generate the partitioning sequence minimizes the overhead of onboard flow table storage space while ensuring routing effectiveness.

[0077] Preferably, in response to the high topology dynamism generated when satellite nodes move to mid-latitude intersection regions, the satellite routing controller performs fine-grained sampling processing for active states. In mid-latitude regions, due to frequent convergences of satellites in opposite orbits and rapid connection and disconnection of multiple links, the generated topology change rate exhibits significant peak characteristics. Once the satellite routing controller detects that the value exceeds a threshold, it immediately reduces the time step corresponding to that period to a short-period step (e.g., selecting five seconds as the discrete cutting interval). This processing action increases the time-domain sampling frequency to ensure that the generated network-wide topology snapshot can completely capture every critical link switching node. This high-frequency slicing method ensures that the global routing flow table generated in a dynamic environment has extremely high timeliness consistency, avoiding the routing black hole problem caused by excessively large step sizes.

[0078] Preferably, the satellite routing controller acquires the established long-period step size and short-period step size and injects them as time control variables into the sequence organization engine. During execution, multiple time slot units of varying lengths are chained together according to the evolution order of the predicted time axis, thereby constructing a partitioning sequence reflecting the topology fragmentation configuration of future time periods. Each sequence consists of a start timestamp, an end timestamp, and associated step size attributes, forming a digital calendar describing the network evolution logic. This processing step achieves a fundamental leap from single physical quantity characteristics to system-level scheduling sequences. The generated partitioning sequence is written to a cache table in real time, serving as the triggering benchmark for subsequent large-scale parallel computation of routing paths in each time slot.

[0079] Preferably, through the aforementioned variable-length slicing logic driven by the topology change rate, the satellite routing controller ultimately generates the partition sequence composed of time slot units of different durations. This non-equidistant partitioning mechanism, at its core, alleviates the contradiction between routing accuracy and storage load in large low-Earth orbit satellite constellations. The generated partition sequence enables subsequent routing update packets to be precisely anchored at the moment when a substantial change occurs in the topology, while maintaining an extremely low update frequency during stable operation. This series of closely linked processing actions establishes the ability of this application to achieve predictive routing updates in a scenario completely independent of inter-satellite link detection, significantly improving the continuity and stability of inter-satellite data packet forwarding in complex geographical regions such as polar and mid-latitude areas, and achieving efficient scheduling and smooth evolution of network-wide traffic.

[0080] Optionally, the satellite routing controller uploads the routing update package to the target satellite node, including: when the target satellite node passes through the coverage area of ​​the ground base station, the satellite routing controller uploads the routing update package containing a future preset time period to the target satellite node via the power supply link to perform pre-buried storage.

[0081] Preferably, the satellite routing controller accurately identifies the communication reachability between the satellite and the ground base station by real-time monitoring of the orbit prediction data of each target satellite node, thereby establishing the logical trigger point for data upload. When the selected target satellite node is detected to be operating within the coverage area of ​​the ground base station, the satellite routing controller automatically retrieves the future incremental dataset matching the physical identifier of the satellite node from the routing configuration database. For these time-series-arranged routing change information, the satellite routing controller performs data aggregation processing according to a preset future duration (e.g., selecting the next hour's operating cycle as the prediction window), and encapsulates the generated binary instruction stream into a routing update packet containing logical check bits and a time index identifier. This action enables centralized preparation of future long-term topology change information at the instant the satellite-to-ground link is established. The generated routing update packet carries all the prior path knowledge required by the satellite after leaving the ground station's coverage arc, providing complete data source support for subsequent cross-regional autonomous routing maintenance.

[0082] Preferably, the satellite routing controller drives the ground radio frequency front-end system to establish a feed link with the target satellite node and executes a high-speed uplink transmission task for the generated routing update packet. In the specific processing, the satellite routing controller converts the routing update packet into a modulated signal stream with high anti-interference characteristics according to a preset physical layer link protocol and injects it into the feed link. This action realizes the physical migration of the routing instruction set containing a large amount of topology prediction information from the ground-based centralized processing environment to the onboard distributed execution environment. This large-scale injection method, executed during a single transit, avoids the inefficient mode of performing real-time update signaling interaction when the constellation topology undergoes substantial changes. The update packet issued through the feed link, because it contains differentiated patches for multiple future time slot units, ensures that the satellite still has accurate flow table update basis during subsequent offline operation, significantly alleviating the bandwidth dependence pressure on the satellite-ground control link when the satellite constellation experiences high-frequency topology changes.

[0083] Preferably, the target satellite node captures radio frequency energy from the feed link and performs downconversion and bitstream restoration processing to obtain the complete routing update packet. Subsequently, the target satellite node drives its onboard storage controller logic to perform pre-embedded storage for the extracted routing update packet. In the specific storage execution phase, the target satellite node sequentially writes routing change entries containing indices of different time steps into a flow table sequence buffer defined in the local physical medium. This processing action enables the construction of a "routing policy reserve" with temporal depth on the onboard side, ensuring that each pre-generated flow table increment is anchored to a predetermined future effective time. Through this pre-embedded storage, even in ground signaling blind spots during subsequent operation, the target satellite node can accurately retrieve the corresponding flow table patch from the flow table sequence buffer and perform atomic switching based on the triggering guidance of the onboard high-precision synchronization clock.

[0084] Preferably, the aforementioned inoculation action initiated by the satellite routing controller and the pre-embedded storage action executed by the target satellite node form a deep technical support for "zero signaling overhead" real-time routing updates. Without the batch distribution of future preset duration information executed during transit, satellite nodes would be unable to maintain the continuous validity of their forwarding state in the complex inter-satellite link environment. By performing pre-embedded storage in the satellite's local medium, the signaling interaction that originally required real-time consumption of satellite-ground bandwidth is transformed into a satellite-local memory scheduling action. This processing method ensures that each routing update packet exists in a pre-embedded state in the forwarding options of the target satellite node before it is actually activated, thus providing definite physical material for the subsequent atomic switching of the execution logic mapping relationship at the instantaneous time slot unit boundary. This complete link from ground prediction calculation, centralized link inoculation to satellite pre-embedded storage establishes the satellite network's autonomous evolution capability to cope with second-level dynamic topology, ensuring the routing continuity and forwarding stability of data packets during inter-satellite migration.

[0085] like Figure 2 As shown in the figure, a time-slicing prediction-based SDN routing update system for low-Earth orbit satellite networks is provided in an embodiment of this application. The system includes a satellite routing controller, which executes any of the time-slicing prediction-based SDN routing update methods for low-Earth orbit satellite networks as described in the above embodiment of this application to generate a routing update packet and upload it to the target satellite node.

[0086] This application embodiment also provides a method for generating and sending route update packets, which includes: the ground calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of satellite nodes to generate a time-step partition sequence; the ground constructs a corresponding overall network topology snapshot based on the time-step partition sequence to generate a global routing flow table; the ground generates a route update packet based on the global routing flow table and uploads it to the target satellite node.

[0087] This application embodiment also provides a method for receiving and switching satellite routing flow tables, which includes: a target satellite node receiving a routing update packet uploaded from the ground; the target satellite node responding to a trigger signal generated by a network-wide synchronization clock, controlling a shadow flow table preloaded with flow table increments to atomically switch to the current flow table based on the routing update packet, and performing data forwarding based on the current flow table.

[0088] This application also provides a satellite routing controller, which is deployed on the ground and is used to perform the following steps: calculating the overall network topology evolution trend by acquiring the orbital dynamic parameters of satellite nodes to generate a time-step partition sequence; constructing a corresponding overall network topology snapshot based on the time-step partition sequence to generate a global routing flow table; and generating a routing update packet based on the global routing flow table and uploading it to the target satellite node.

[0089] This application also provides a satellite communication node for performing the following steps: Receive the route update packets uploaded from the ground; In response to the trigger signal generated by the network-wide synchronization clock, the shadow flow table with preloaded flow table increments is atomically switched to the current flow table based on the route update packet, and data forwarding is performed based on the current flow table.

[0090] This application also provides a computer storage medium storing computer-executable instructions thereon, which are executed to implement the methods described in any embodiment of this application.

[0091] Figure 2 For exemplary explanations in other embodiments, please refer to the above. Figure 1 .

[0092] The above description is merely an exemplary embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for SDN routing update in low-Earth orbit satellite networks based on time-slicing prediction, characterized in that, include: Step 1: The ground system calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of the satellite nodes in order to generate a time-step partitioning sequence; Step 2: The ground system constructs a corresponding full-network topology snapshot based on the time step division sequence to generate a global routing flow table; Step 3: The ground system generates a routing update packet based on the global routing flow table; Step 4: The ground system uploads the routing update packet to the target satellite node in response to the trigger signal generated by the full-network synchronization clock, controls the atomized switching of the shadow flow table preloaded with the flow table increment to the current flow table, and performs data forwarding based on the current flow table.

2. The method for SDN routing update in low-Earth orbit satellite networks based on time-slicing prediction according to claim 1, characterized in that, In step 1, the ground unit calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of the satellite nodes, including: the ground unit performs time-varying analysis of link connectivity based on the orbital dynamic parameters to obtain the topology change rate reflecting the frequency of link increases and decreases in the entire network; the ground unit determines the time step of each time slot unit in the partitioned sequence by comparing the topology change rate with a preset change rate threshold.

3. The method for SDN routing update in low-Earth orbit satellite networks based on time-slicing prediction according to claim 1, characterized in that, In step 2, the ground constructs a corresponding network topology snapshot based on the time step division sequence to generate a global routing flow table. This includes: for each time slot unit in the division sequence, the ground constructs a graph theory topology structure consisting of a set of nodes and a set of links based on the orbital dynamics parameters, as a network topology snapshot; the ground uses the Dijkstra algorithm to perform shortest path optimization on the network topology snapshot to determine the global routing flow table corresponding to each time slot unit.

4. The method for SDN routing update in low-Earth orbit satellite networks based on time-slicing prediction according to claim 1, characterized in that, In step 3, the ground-based generation of route update packets based on the global routing flow table includes: the ground-based execution of differential subtraction on two global routing flow tables that are temporally adjacent to each other to extract flow table increments containing only flow table change entries; and the ground-based execution of incremental encoding compression processing on the flow table increments through a flow table compression engine to obtain route update packets with reduced signaling volume.

5. The method for SDN routing update in low-Earth orbit satellite networks based on time-slicing prediction according to claim 1, characterized in that, In step 4, before the target satellite node controls the atomic switching of the shadow flow table preloaded with the flow table increment to the current flow table, the following steps are also included: the target satellite node receives the routing update packet through the uplink and performs decompression and data verification on the routing update packet to store the decompressed flow table increment into the flow table sequence buffer.

6. A method for generating and sending route update packets, characterized in that, include: The ground-based system calculates the overall network topology evolution trend by acquiring the orbital dynamic parameters of the satellite nodes, in order to generate a time-step partitioning sequence; Based on the time step division sequence, the ground constructs a corresponding full network topology snapshot to generate a global routing flow table; The ground-based system generates a route update packet based on the global routing flow table and uploads it to the target satellite node.

7. A method for receiving and switching satellite routing flow tables, characterized in that, include: The target satellite node receives the route update packet uploaded from the ground; The target satellite node responds to the trigger signal generated by the network-wide synchronization clock, and controls the preloaded shadow flow table with flow table increments to atomically switch to the current flow table based on the route update packet, and performs data forwarding based on the current flow table.

8. A satellite routing controller, characterized in that, Deployed on the ground, it performs the following steps: calculating the overall network topology evolution trend by acquiring the orbital dynamic parameters of satellite nodes to generate a time-step partition sequence; and constructing a corresponding overall network topology snapshot based on the time-step partition sequence to generate a global routing flow table. A route update packet is generated based on the global routing flow table and uploaded to the target satellite node.

9. A satellite communication node, characterized in that, It is used to perform the following steps: Receive the route update packets uploaded from the ground; In response to the trigger signal generated by the network-wide synchronization clock, the shadow flow table with preloaded flow table increments is atomically switched to the current flow table based on the route update packet, and data forwarding is performed based on the current flow table.

10. A computer storage medium, characterized in that, It stores computer-executable instructions thereon, which are executed to implement the method according to any one of claims 1-7.

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