Low-orbit satellite network dynamic routing optimization method and system based on sub-domain routing

Abstract

The application provides a low-orbit satellite network dynamic routing optimization method and system based on sub-domain routing, which comprises the following steps: dividing a satellite network into multiple areas, and assigning a unique IP address to each satellite node; in each area, synchronizing intra-domain topology information through Hello data packets and link state advertisements to generate an intra-domain routing table; synchronizing inter-domain topology information through border gateways and summary link state advertisements to generate an inter-domain routing table; and forwarding data packets according to the intra-domain and inter-domain routing tables. The application can reduce signaling overhead, improve routing calculation efficiency, enhance network stability, and optimize network resource utilization.

Description

Technical Field

[0001] This invention relates to the field of satellite communication networks and routing algorithms, and in particular to a dynamic routing optimization method and system for low-Earth orbit satellite networks based on domain-based routing. Background Technology

[0002] Satellite networks are characterized by full coverage, dynamic topology, and highly dynamic links, making it difficult to directly apply traditional terrestrial routing protocols.

[0003] Dynamic routing strategies for satellite networks aim to address dynamic changes in satellite topology using three methods: topology planarization, virtual nodes, and virtual topology. Topology planarization treats the entire Low Earth Orbit (LEO) satellite network as a two-dimensional plane, assigning each satellite fixed logical coordinates to mask network topology dynamics. Virtual node routing algorithms address the challenges of dynamic topologies by dividing coverage areas and constructing a satellite network model composed of multiple coverage areas. Each coverage area is abstracted as a virtual node and assigned fixed coordinates. Virtual topology algorithms divide the satellite's operational cycle into multiple time intervals, assuming the satellite network topology remains constant between these intervals. Routes for the current time are calculated first by ground stations and then distributed to all satellites in the network.

[0004] As satellite networks expand, the routing tables maintained by routers increase proportionally, consuming more and more buffer space and CPU computing power, and using more bandwidth to exchange routing state information. Therefore, routing must be performed hierarchically, that is, routes are divided into intra-domain routes and inter-domain routes, and calculated separately.

[0005] Existing hierarchical routing algorithms mainly employ the hierarchical routing algorithms of the OSPF and DHRP protocols.

[0006] The OSPF (Open Shortest Path First) protocol's hierarchical routing algorithm divides an autonomous system into multiple areas, each with a unique identifier (Area ID). The backbone area (Area 0) is directly connected to other areas and is responsible for exchanging routing information between areas. Intra-area routing calculations use link-state routing algorithms, while inter-area routing is achieved through Type-3 Link-State Advertisements (LSAs), generated and transmitted by Area Border Routers (ABRs). Loop prevention mechanisms are implemented, such as requiring inter-area routes to pass through Area 0, and ABRs only advertising routing information for directly connected areas to Area 0. This algorithm reduces the amount of routing information exchanged by dividing the system into areas, and the hierarchical design simplifies routing calculations and management. However, Area 0 becomes a potential single point of failure; if Area 0 fails, the stability of the entire network will be affected. Furthermore, all traffic from non-backbone areas must pass through Area 0, potentially causing excessive traffic pressure on the backbone area. Additionally, Area Border Routers only transmit overall information, which may lead to suboptimal route selection.

[0007] DHRP (Distributed Hierarchical Routing Protocol) is a hierarchical routing protocol for single-layer satellite networks. It divides satellite networks into regions based on orbits, with each orbit forming its own region. Each orbit elects an orbital loudspeaker (PS) responsible for synchronizing link-state information between regions. The orbital loudspeaker summarizes the link-state information within its orbit, generating an S-LSA (Summary Link State Advertisement), and synchronizes it with PSs on adjacent orbits. The PS uses an extended Dijkstra algorithm to calculate hierarchical routes, generating the optimal primary path and the next best secondary path. This algorithm divides regions by orbit, reducing the scope of inter-regional link-state information synchronization, and simplifies routing calculations by synchronizing information between regions through the PS. However, when the link or node where the orbital loudspeaker is located fails, the overhead is enormous, affecting network stability. Furthermore, the storage and computational pressure on the orbital loudspeaker is significant, leading to wasted onboard resources. Since all nodes can potentially become orbital loudspeakers, the system design needs to reserve sufficient storage space and computing power for each node, increasing costs. Summary of the Invention

[0008] In view of this, embodiments of the present invention provide a method and system for dynamic routing optimization of low-Earth orbit satellite networks based on domain routing, so as to eliminate or improve one or more defects existing in the prior art.

[0009] On the one hand, the present invention provides a dynamic routing optimization method for low-Earth orbit satellite networks based on domain-based routing, the method comprising the following steps:

[0010] The satellite network is divided into multiple regions, each containing a fixed number of orbits and satellite nodes corresponding to each orbit; a unique IP address is assigned to each satellite node; the boundaries of each region are determined and a border gateway is elected;

[0011] Within each region, each satellite node establishes neighbor relationships and generates topology connections by sending Hello packets and receiving Hello packets from other satellite nodes. Each satellite node generates a link-state advertisement based on its own topology connections and forwards it to neighboring nodes within the same region. Other satellite nodes add the received link-state advertisements to their local link-state databases and forward them to other neighbors until the link-state databases of all satellite nodes within the region are consistent. Each satellite node calculates the optimal path to other nodes within the region based on its local link-state database and generates an intra-domain routing table.

[0012] Between regions, each region's border gateway generates a summary link status announcement, which is unicasted to the border gateways of adjacent regions via inter-domain links and flooded within its own region; other border gateways verify the received summary link status announcements, and if they determine that it is a new summary link status announcement, they store it and flood it within their own region; each border gateway calculates the optimal path to other regions based on the summary link status announcement and generates an inter-domain routing table.

[0013] Packet forwarding is performed based on the intra-domain routing table and the inter-domain routing table.

[0014] In some embodiments of the present invention, a unique IP address is assigned to each satellite node, including:

[0015] The IP address structure of a satellite node includes a network address prefix, an area code, the satellite node number within that area, and the port number, as shown in the formula:

[0016] Node IP=Prefix+Area Id+Statellite Id+Interface Id;

[0017] Wherein, Node IP represents the IP address of the satellite node; Prefix represents the network address range prefix; Area Id represents the area number; StateId represents the satellite node number within the area; and Interface Id represents the port number.

[0018] In some embodiments of the present invention, the method further includes:

[0019] In the satellite network, satellites are classified according to their function and location, including ordinary nodes and area boundary routers; wherein, the area boundary routers are used to connect satellite nodes in different areas;

[0020] Within each region, the region border router with the lowest cost value is elected as the region's border gateway.

[0021] In some embodiments of the present invention, each satellite node generates a link status announcement based on its own topology connectivity, including:

[0022] The link status announcement includes a common header and connection content;

[0023] Add an area number to the common header to limit the propagation range of the link status announcement to the area corresponding to the area number.

[0024] In some embodiments of the present invention, each satellite node calculates the optimal path to other nodes within the region based on its local link-state database and generates an intra-domain routing table, including:

[0025] Each satellite node uses the shortest path first algorithm based on its local link state database to calculate the optimal path to other nodes in the region and generates routing table entries, which are then stored to obtain the intra-domain routing table.

[0026] The entries in the intra-domain routing table include the destination IP address, subnet mask, next-hop IP address, and routing cost.

[0027] In some embodiments of the present invention, after information synchronization within the region is completed and before information synchronization between regions is completed, the method further includes:

[0028] Each region and its internal satellite nodes form the underlying domain network;

[0029] The entire region is abstracted into a single logical node and identified by a unique region number to construct a top-level inter-domain network; the abstracted logical node serves as the boundary gateway for adjacent regions.

[0030] When two regions communicate through their respective border gateways, the communication cost is determined by the minimum overhead of all possible links between the two regions.

[0031] In some embodiments of the present invention, each border gateway calculates the optimal path to other areas based on the summarized link state advertisement and generates an inter-domain routing table, including:

[0032] Each border gateway calculates the optimal path to other areas and generates routing table entries based on the aggregated link status announcement, using the shortest path first algorithm, and stores them to obtain the inter-domain routing table;

[0033] The entries in the inter-domain routing table include the destination area network segment, the destination area number, the next-hop area number, and the next-hop IP address.

[0034] In some embodiments of the present invention, the boundary gateway of each region generates a summary link status announcement between regions, further comprising:

[0035] The summary link status announcement carries an incrementing sequence number, a time-to-live field, and a unique identifier;

[0036] The sequence number is maintained by the border gateway that generates the summary link status announcement and increments each time a new summary link status announcement is generated. When the border gateway receives a summary link status announcement, it determines whether it is a new summary link status announcement by confirming the sequence number, and decides whether to store and forward it.

[0037] Each time the aggregated link status announcement is forwarded, the time-to-live field is incremented; when the time-to-live field reaches a preset maximum value, the aggregated link status announcement is discarded.

[0038] The border gateway maintains a forwarded list to record the identifiers of processed summary link state announcements. When the border gateway receives a summary link state announcement, it checks whether its identifier already exists in the forwarded list maintained by the border gateway. If it exists, it discards the announcement; otherwise, it forwards it.

[0039] In some embodiments of the present invention, after obtaining the intra-domain routing table and the inter-domain routing table, the method further includes:

[0040] If a link failure occurs in the region, the faulty node generates a new link status announcement and floods it in the region, triggering all satellite nodes to recalculate and generate the intra-domain routing table.

[0041] If a link failure occurs between regions, the border gateway generates a new summary link status announcement and forwards it through other border gateways, triggering all regions to recalculate and generate inter-domain routing tables.

[0042] Each satellite node updates its intra-domain routing table and inter-domain routing table to forward data packets.

[0043] On the other hand, the present invention also provides a dynamic routing optimization system for low-Earth orbit satellite networks based on domain-based routing, the system comprising:

[0044] The network domaining and addressing module is used to divide the satellite network into multiple regions and assign a unique IP address to each satellite node;

[0045] The intra-domain routing information synchronization module is used to synchronize the topology information of satellite nodes in each region and generate intra-domain routing tables.

[0046] The inter-domain routing information synchronization module is used to synchronize topology information between regions and generate inter-domain routing tables.

[0047] The data forwarding module is used to forward data packets according to the generated intra-domain routing table and inter-domain routing table.

[0048] This invention provides a method and system for dynamic routing optimization of low-Earth orbit satellite networks based on domain routing, comprising: dividing the satellite network into multiple regions and assigning a unique IP address to each satellite node; within each region, synchronizing intra-regional topology information through Hello packets and link state advertisements to generate an intra-regional routing table; synchronizing inter-regional topology information through border gateways and aggregated link state advertisements to generate an inter-regional routing table; and forwarding data packets according to the intra-regional and inter-regional routing tables.

[0049] Specifically, this invention uses a domain-based routing mechanism to restrict topology information synchronization to local areas, reducing signaling flooding across the entire network and significantly lowering signaling overhead. Through hierarchical routing calculations within and between domains, the complexity of routing calculations is reduced, improving efficiency and response speed.

[0050] Furthermore, by dynamically updating the routing table and quickly handling link failures, the impact of single-point failures on the entire network is avoided, enhancing network stability and robustness. Through reasonable domain design and boundary gateway mechanisms, the traffic pressure problem in the backbone area of ​​the traditional OSPF protocol is avoided. Network resource utilization is optimized. Through routing algorithms based on topology snapshots and timely management of aggregated link-state advertisements, the highly dynamic topology changes of low-Earth orbit satellite networks can be effectively addressed, ensuring the real-time nature and accuracy of routing information.

[0051] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows, and will also become apparent in part to those skilled in the art upon studying the description, or may be learned by practice of the invention. The objects and other advantages of the invention can be realized and obtained by means of the structures specifically pointed out in the specification and drawings.

[0052] Those skilled in the art will understand that the objectives and advantages achievable with the present invention are not limited to those specifically described above, and that the above and other objectives achievable with the present invention will become clearer from the following detailed description. Attached Figure Description

[0053] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, are not intended to limit the scope of the invention. In the drawings:

[0054] Figure 1 This is a schematic diagram illustrating the steps of a dynamic routing optimization method for low-Earth orbit satellite networks based on domain-based routing in one embodiment of the present invention.

[0055] Figure 2 This is a schematic diagram of the process of information synchronization within a domain in one embodiment of the present invention.

[0056] Figure 3 This is a schematic diagram of the inter-domain routing structure in one embodiment of the present invention.

[0057] Figure 4 This is a schematic diagram of the process of inter-domain information synchronization in one embodiment of the present invention.

[0058] Figure 5 This is a schematic diagram of the global topology in one embodiment of the present invention.

[0059] Figure 6 This is a schematic diagram of the topological relationship between regions in one embodiment of the present invention. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0061] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0062] 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.

[0063] 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.

[0064] In the following description, embodiments of the invention 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.

[0065] It should be emphasized here that the step markers mentioned below are not a limitation on the order of the steps, but should be understood as meaning that the steps can be executed in the order mentioned in the embodiments, or in a different order than in the embodiments, or several steps can be executed simultaneously.

[0066] To address the problems of single-point failures in backbone areas, high traffic pressure, and heavy storage and computational burden on orbital loudspeakers in existing hierarchical routing algorithms, leading to wasted onboard resources and high repair costs during failures, this invention provides a dynamic routing optimization method for low-Earth orbit satellite networks based on domain-based routing. Figure 1 As shown, the method includes the following steps S101 to S104:

[0067] Step S101: Divide the satellite network into multiple regions, each region containing a fixed number of orbits and satellite nodes corresponding to each orbit; assign a unique IP address to each satellite node; determine the boundary of each region and elect a boundary gateway.

[0068] Step S102: Within each region, each satellite node establishes neighbor relationships and generates topology connections by sending Hello packets and receiving Hello packets from other satellite nodes; each satellite node generates a link-state advertisement based on its own topology connections and forwards it to neighboring nodes within the same region; other satellite nodes add the received link-state advertisements to their local link-state databases and forward them to other neighbors until the link-state databases of all satellite nodes within the region are consistent; each satellite node calculates the optimal path to other nodes within the region based on its local link-state database and generates an intra-domain routing table.

[0069] Step S103: Between regions, the border gateway of each region generates a summary link status announcement, sends it to the border gateways of adjacent regions via inter-domain links via unicast, and floods it within its own region; other border gateways verify the received summary link status announcements, and if they determine that it is a new summary link status announcement, they store it and flood it within their own region; each border gateway calculates the optimal path to other regions based on the summary link status announcement and generates an inter-domain routing table.

[0070] Step S104: Forward data packets according to the intra-domain routing table and the inter-domain routing table.

[0071] In step S101, the satellite network is divided into multiple regions, each containing a fixed number of orbits and satellites per orbit, with adjacent regions connected via border gateways. A unique IP address is assigned to each satellite node.

[0072] In some embodiments, the address range design of the satellite network supports both IPv4 (Internet Protocol Version 4) and IPv6 (Internet Protocol Version 6) formats, providing good flexibility and scalability.

[0073] In some embodiments, the IP address structure of satellite nodes is simplified for ease of representation, serving as the address range of the satellite network. As shown in formula (1), the IP address structure of the satellite node is as follows:

[0074] Node IP=Prefix+Area ID+Statellite ID+Interface ID; (1)

[0075] Wherein, Node IP represents the IP address of the satellite node; Prefix represents the network address range prefix; Area ID is the area number, indicating the area to which the satellite node belongs; State ID represents the number of the satellite node within the area; and Interface ID represents the port number, used to identify the interface of the satellite node.

[0076] Therefore, the composition of the IP field of the satellite node is shown in Table 1:

[0077] Table 1 Composition of Satellite Node IP Fields

[0078] Prefix Area ID Satellite ID Interface ID

[0079] In step S102, the topology information of satellite nodes is synchronized in each region to generate an intra-domain routing table.

[0080] like Figure 2 The diagram shows a flowchart of information synchronization within the domain. Specifically, at the beginning of each time slot, satellite nodes within the area send Hello packets containing information such as the Area ID from their ports to announce their presence. Other satellite nodes receive these packets, extract the Area ID, and determine if it matches their own. If they match, they belong to the same area; otherwise, they do not. Each satellite node then marks itself as an Area Border Router (ABR), establishes neighbor relationships with adjacent satellite nodes, and generates a topology connection, including information such as neighbor nodes and link costs. Each satellite node generates a Link State Advertisement (LSA) based on its own topology connection.

[0081] In some embodiments, the description of the link-state advertisement within each link-state advertisement entry can be divided into a common header and connection content. The common header primarily describes the attributes of the link-state advertisement, such as link-state type, identifier ID, source, sequence number, and checksum length. An area number is added to the original common header to limit the propagation scope of the link-state advertisement to the area corresponding to that area number.

[0082] Table 2 shows the fields included in the Link State Advertisement (LSA) common header and their meanings.

[0083] Table 2 Composition of the Link State Advertisement Common Header

[0084]

[0085]

[0086] The router link-state advertisement (LSI) includes a description of the satellite node topology. This mainly includes the following: satellite node interface IP, neighbor node IP, neighbor node router ID, and corresponding link cost. Table 3 shows the fields included in the router link-state advertisement and their meanings.

[0087] Table 3. Composition of Router Link State Advertisement Messages

[0088]

[0089] Each satellite node within the region maintains a retransmission list and a local link state database (LSDB). Each satellite node adds a link state advertisement to the retransmission list and forwards it to neighboring nodes within the same region. Upon receiving confirmation from a neighboring node, the corresponding link state advertisement is removed from the retransmission list.

[0090] When other satellite nodes receive a link state announcement forwarded by their neighbor, they add the announcement to their local link state database and continue to forward it to neighboring nodes in the same area through a retransmission list until the link state databases of all satellite nodes in the area are consistent, thus completing the intra-domain information synchronization.

[0091] After the link-state database synchronization is completed, each satellite node within the region has completed the construction of the regional topology view. Based on this, each satellite node runs the Shortest Path First (SPF) algorithm, also known as Dijkstra's algorithm, to calculate the shortest path, or optimal path, to other nodes within the region, and then generates routing table entries. These routing table entries are stored in a pre-defined routing table to generate an intra-domain routing table. For example, an entry in the intra-domain routing table is structured as <destination IP address, subnet mask, next-hop IP address, routing cost>.

[0092] In step S103, topology information is synchronized between regions to generate an inter-domain routing table.

[0093] In some embodiments, after the intra-domain link-state database synchronization is completed, the regional border router with the lowest cost value is elected from the regional border routers as the border gateway of the region. The border gateway sends a gateway declaration to other regional border routers connected to the same neighboring region to announce that the border gateway election is complete.

[0094] Dividing a large-scale satellite network into multiple regions can effectively reduce the flooding scope and number of topology information synchronization control messages across the entire network. However, due to the still large number of nodes in each region and the overall region size, the intra-regional summary message messages sent during inter-regional topology information updates are quite long, consuming significant network resources. Therefore, this invention proposes a method for abstracting each region as a node for inter-regional routing calculation, such as... Figure 3 As shown.

[0095] In satellite networks, satellites are categorized into ordinary nodes and Area Border Routers (ABRs) based on their function and location. Ordinary nodes are the basic units of the satellite network, primarily responsible for forwarding data and calculating routes for Link-State Advertisements (LSAs) and Summary LSAs within their domain. Area Border Routers connect different areas and are responsible for electing border gateways, forwarding data for intra-domain LSAs, and calculating routes for Summary LSAs. After calculating the next area ID based on the Summary LSA information, the network routing table and Summary LSA information are consulted to select the Area Border Router with the lowest cross-domain cost as the area's exit point. A border gateway is an Area Border Router with the lowest cost value on the boundary of a neighboring area. It is responsible for generating Summary LSAs and relaying all Summary LSAs received by that area to its neighboring areas. The number of border gateways equals the number of neighboring areas of an area.

[0096] Based on the above node identity definition, such as Figure 3 As shown, each region and its internal satellite nodes form the underlying intra-domain network. The entire region (including all nodes within the region) is abstracted into a single logical node, identified by a unique region number, to construct the top-level inter-domain network. This abstracted logical node serves as the boundary gateway between adjacent regions. When two regions communicate through their respective boundary gateways, the communication cost is determined by the minimum overhead of all possible links between the two regions. This approach not only simplifies routing management but also significantly reduces signaling overhead, thereby improving the overall network operating efficiency.

[0097] like Figure 4 The diagram shows a flowchart of inter-domain information synchronization. After the boundary gateway of each region completes intra-domain information synchronization, it generates a summary link status announcement for the current region and its directly adjacent regions. This announcement is then unicasted to the boundary gateways of the corresponding adjacent regions via inter-domain links and flooded within its own region.

[0098] For any node within a given area, all inter-domain link-state information is stored. This inter-domain link information is stored using a special type of link-state advertisement called Summary Link-State Advertisement (SLSA), which summarizes the cross-domain link information of all area border routers within the same neighboring area. The Summary Link-State Advertisement summarizes the neighbor relationships between areas, as shown in Table 4. It includes a Time-to-Live (Age) field, the corresponding area border router's IP address, local area number, neighboring area number, and the link cost between areas. Routers within the area can obtain the router IDs and IP addresses of the border gateway and area border routers by parsing the information encapsulated in the Summary Link-State Advertisement, thus providing the necessary data support for the next stage of route calculation.

[0099] Table 4 summarizes the composition of the link status announcement message body.

[0100]

[0101]

[0102] When other (adjacent) border gateways receive the summarized link status announcement, they first perform a uniqueness check on the announcement using information such as the generating area number, border gateway IP address, and adjacent area number. If a duplicate is found, it is discarded; otherwise, it is stored. When a new summarized link status announcement is received, it is stored and then flooded to all border gateways within the same region via intra-domain links, ensuring that other border gateways in the same region synchronize the information. By repeating the above steps, the summarized link status announcement gradually covers all regions through relay forwarding by border gateways, completing inter-domain information synchronization.

[0103] After inter-domain information synchronization is completed, each border gateway calculates the shortest path (i.e., the optimal path) to other regions based on the summarized link state advertisement using the Shortest Path First (SPF) algorithm, also known as Dijkstra's algorithm. This results in the generation of routing table entries, which are then stored in a pre-defined routing table to create an inter-domain routing table. For example, an entry in the inter-domain routing table is structured as <destination area network segment, destination area number, next-hop area number, next-hop IP address>.

[0104] In some embodiments, as shown in Table 4, the summary link status announcement carries an incrementing sequence number, a time-to-live field, and a unique identifier.

[0105] The sequence number is maintained by the border gateway that generates the summary link state announcement and increments each time a new summary link state announcement is generated. When the border gateway receives a summary link state announcement, it compares the sequence number to determine the age of the information. If it is an older summary link state announcement, it is discarded to avoid overwriting new information. If it is a new summary link state announcement, it is stored and forwarded.

[0106] Each time the summary link-state announcement is forwarded, the Time-to-Live (TTL) field is incremented. When the TTL field reaches a preset maximum value, the summary link-state announcement is discarded to prevent outdated information from spreading indefinitely across the network.

[0107] Border gateways maintain a forwarded list to record the identifiers of processed summary link-state advertisements (SLAs). When a border gateway receives a SEA, it checks if its identifier already exists in the forwarded list. If it does, the SEA discards the advertisement; otherwise, it forwards it. Furthermore, the forwarded list is periodically cleaned up, and expired records are deleted to reduce storage and computational overhead.

[0108] By setting sequence numbers and unique identifiers, it is possible to ensure that new information replaces old information in a timely manner and avoids duplicate forwarding. The Time-to-Live (TTL) field and the forwarded list further limit the scope and duration of the summarized link-state announcement's propagation, preventing loops and the retention of outdated information. These designs collectively ensure the efficient and reliable propagation of summarized link-state announcements, while reducing network overhead and ensuring the consistency and timeliness of network topology information.

[0109] In step S104, data packets are forwarded according to the intra-domain routing table and the inter-domain routing table. Specifically, if the destination node is in the same area, the intra-domain routing table is consulted, and the shortest path is selected to forward the data packet; if the destination node is in another area, the inter-domain routing table is consulted, and the optimal border gateway is selected for cross-domain forwarding. The optimal path is dynamically selected based on the cost information in the routing table to ensure efficient data transmission.

[0110] In some embodiments, dynamically maintaining the routing table and handling link failures includes:

[0111] If a link failure occurs within the region, the faulty node generates a new link status announcement and floods it within the region, triggering all satellite nodes to recalculate and generate intra-domain routing tables.

[0112] If a link failure occurs between regions, the border gateway generates a new summary link status announcement and forwards it through other border gateways, triggering all regions to recalculate and generate inter-domain routing tables.

[0113] Each satellite node updates its intra-domain routing table and inter-domain routing table to forward data packets.

[0114] The present invention will be further described below with reference to a specific embodiment.

[0115] Based on the domain routing mechanism, the satellite network is divided. In this embodiment, for example... Figure 5 As shown, the satellite network is divided into 4 regions, with 9 nodes in each region. The region border router with the lowest cost value is elected as the border gateway for that region (the darker gray nodes in the diagram represent the border gateways).

[0116] Based on the method mentioned above of abstracting each region as a node for inter-domain routing calculation, we obtain... Figure 6 A schematic diagram of the topological relationships between regions.

[0117] After obtaining the intra-domain and inter-domain topological relationships, the intra-domain routing table and the inter-domain routing table are calculated using the dynamic routing optimization method for low-Earth orbit satellite networks based on domain routing provided by this invention, as shown in Table 5 and Table 6, respectively.

[0118] Table 5 Intra-domain Routing Table

[0119]

[0120] Table 6 Inter-domain routing table

[0121]

[0122] Corresponding to the domain-based routing dynamic routing optimization method for low-Earth orbit satellite networks, this invention also provides a domain-based routing dynamic routing optimization system for low-Earth orbit satellite networks, the system comprising:

[0123] The network domaining and addressing module is used to divide the satellite network into multiple regions and assign a unique IP address to each satellite node.

[0124] The intra-domain routing information synchronization module is used to synchronize the topology information of satellite nodes in each region and generate intra-domain routing tables.

[0125] The inter-domain routing information synchronization module is used to synchronize topology information between regions and generate inter-domain routing tables.

[0126] The data forwarding module is used to forward data packets according to the generated intra-domain routing table and inter-domain routing table.

[0127] Corresponding to the above method, the present invention also provides an electronic device including a computer device, the computer device including a processor and a memory, the memory storing computer instructions, the processor executing the computer instructions stored in the memory, and when the computer instructions are executed by the processor, the electronic device performs the steps of the method as described above.

[0128] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the aforementioned edge computing server deployment 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.

[0129] 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 invention. 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 invention are programs or code segments used to perform the desired tasks. The programs or code segments can be stored in a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried in a carrier wave.

[0130] It should be clarified that the present invention 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 the present invention 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 the present invention.

[0131] In this invention, 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.

[0132] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations of the embodiments of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A dynamic routing optimization method for low-Earth orbit satellite networks based on domain-based routing, characterized in that, The method includes the following steps: The satellite network is divided into multiple regions, each containing a fixed number of orbits and corresponding satellite nodes for each orbit. Each satellite node is assigned a unique IP address, the structure of which includes a network address prefix, a region number, the satellite node number within that region, and its port number, as shown in the formula: ； in, Indicates the IP address of the satellite node; This indicates the prefix of the network address range; Indicates the area number; This indicates the number of the satellite node within the region; Indicate the port number; determine the boundary of each area and elect the area border router with the lowest overhead value as the boundary gateway of this area; Within each region, each satellite node establishes neighbor relationships and generates topology connections by sending Hello packets and receiving Hello packets from other satellite nodes. Each satellite node generates a link-state advertisement based on its own topology connections and forwards it to neighboring nodes within the same region. Other satellite nodes add the received link-state advertisements to their local link-state databases and forward them to other neighbors until the link-state databases of all satellite nodes within the region are consistent. Each satellite node calculates the optimal path to other nodes within the region based on its local link-state database and generates an intra-domain routing table. Between regions, each region's border gateway generates a summary link status announcement (LSI), which carries an incrementing sequence number, a time-to-live (TTL) field, and a unique identifier. The border gateway maintains a forwarded list to record the identifiers of processed SSIs. It unicasts these SSIs to border gateways in adjacent regions via inter-domain links and floods them within its own region. Other border gateways verify the received SSIs; if they determine it to be a new SSI, they store it and flood it within their own region. Each border gateway calculates the optimal path to other regions based on the SSI and generates an inter-domain routing table. If a link failure occurs within a region, the faulty node generates a new link status announcement and floods it within the region, triggering all satellite nodes to recalculate and generate intra-domain routing tables. If a link failure occurs between regions, the border gateway generates a new summary link status announcement and relays it through other border gateways, triggering all regions to recalculate and generate inter-domain routing tables. Packet forwarding is performed based on the intra-domain routing table and the inter-domain routing table.

2. The dynamic routing optimization method for low-Earth orbit satellite networks based on domain-specific routing according to claim 1, characterized in that, The method further includes: In the satellite network, satellites are classified according to their function and location, including ordinary nodes and area boundary routers; wherein, the area boundary routers are used to connect satellite nodes in different areas.

3. The dynamic routing optimization method for low-Earth orbit satellite networks based on domain-specific routing according to claim 1, characterized in that, Each satellite node generates a link status announcement based on its own topology connectivity, including: The link status announcement includes a common header and connection content; Add an area number to the common header to limit the propagation range of the link status announcement to the area corresponding to the area number.

4. The dynamic routing optimization method for low-Earth orbit satellite networks based on domain-specific routing according to claim 1, characterized in that, Each satellite node calculates the optimal path to other nodes within the region based on its local link-state database and generates an intra-domain routing table, including: Each satellite node uses the shortest path first algorithm based on its local link state database to calculate the optimal path to other nodes in the region and generates routing table entries, which are then stored to obtain the intra-domain routing table. The entries in the intra-domain routing table include the destination IP address, subnet mask, next-hop IP address, and routing cost.

5. The dynamic routing optimization method for low-Earth orbit satellite networks based on domain-specific routing according to claim 1, characterized in that, After information synchronization within the region is completed and before information synchronization between regions is completed, the method further includes: Each region and its internal satellite nodes form the underlying domain network; The entire region is abstracted into a single logical node and identified by a unique region number to construct a top-level inter-domain network; the abstracted logical node serves as the boundary gateway for adjacent regions. When two regions communicate through their respective border gateways, the communication cost is determined by the minimum overhead of all possible links between the two regions.

6. The dynamic routing optimization method for low-Earth orbit satellite networks based on domain-specific routing according to claim 1, characterized in that, Each border gateway calculates the optimal path to other areas based on the summarized link state advertisement and generates an inter-domain routing table, including: Each border gateway calculates the optimal path to other areas and generates routing table entries based on the aggregated link status announcement, using the shortest path first algorithm, and stores them to obtain the inter-domain routing table; The entries in the inter-domain routing table include the destination area network segment, the destination area number, the next-hop area number, and the next-hop IP address.

7. The dynamic routing optimization method for low-Earth orbit satellite networks based on domain-specific routing according to claim 1, characterized in that, Between regions, each region's border gateway generates a summary link status announcement, which also includes: The sequence number is maintained by the border gateway that generates the summary link status announcement and increments each time a new summary link status announcement is generated. When the border gateway receives a summary link status announcement, it determines whether it is a new summary link status announcement by confirming the sequence number, and decides whether to store and forward it. Each time the aggregated link status announcement is forwarded, the time-to-live field is incremented; when the time-to-live field reaches a preset maximum value, the aggregated link status announcement is discarded. When the border gateway receives the summary link status announcement, it checks whether its identifier already exists in the forwarded list maintained by the border gateway. If it exists, it discards the announcement; otherwise, it forwards the announcement.

8. A dynamic routing optimization system for low-Earth orbit satellite networks based on domain-based routing, characterized in that, When the system is executed, it implements the steps of the dynamic routing optimization method for low-Earth orbit satellite networks based on domain routing as described in any one of claims 1 to 7, wherein the system comprises: The network domaining and addressing module is used to divide the satellite network into multiple regions and assign a unique IP address to each satellite node; The intra-domain routing information synchronization module is used to synchronize the topology information of satellite nodes in each region and generate intra-domain routing tables. The inter-domain routing information synchronization module is used to synchronize topology information between regions and generate inter-domain routing tables. The data forwarding module is used to forward data packets according to the generated intra-domain routing table and inter-domain routing table.

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