Satellite-to-ground routing establishment method, electronic device and computer program product

Abstract

Provided in an embodiment of the present invention are a satellite-to-ground routing establishment method, an electronic device and a computer program product, a TV-IP is mapped into network information of a ground node through a satellite-borne router according to a connection state of a satellite and the ground node, the TV-IP being used to identify a connection of the satellite and the ground node; and the satellite-borne router updates the routing information according to the network information of the ground node. The problem that the stability of the whole network is affected due to frequent updating of satellite-borne routing caused by movement of a satellite along an orbit in the prior art is solved, and the effect of ensuring the routing stability between a ground node and the satellite is achieved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of communications, and in particular to a satellite-to-ground routing establishment method, an electronic device, and a computer program product. Background Art

[0002] With the development of network technology and services, space-based and terrestrial networks are gradually moving from independence to interconnection and convergence. A typical interconnection and convergence scenario involves base stations and routers deployed on satellites, with ground gateways serving as the connection boundary between the space-based and terrestrial networks. In this scenario, the space-based bearer network serves as the access and bearer network, while the terrestrial network serves as the core network. Convergence methods for this scenario include Border Gateway Protocol (BGP)-based convergence and tunnel-based convergence.

[0003] In BGP-based convergence, the space and ground networks belong to different autonomous systems (ASs). Inter-AS connectivity and routing interactions are facilitated by external Border Gateway Protocol (EBGP) neighbors. However, BGP closely maps to changes in network topology; when the network topology changes, BGP adjacencies also change. In tunnel-based convergence, the space-based network is considered a system independent of the ground-based network, meaning that routing information from the ground network does not need to be synchronized with the space-based network. When ground network nodes communicate across the space-based network, the ground network is considered a private network and must encapsulate the public network address of the space-based network for data forwarding. Maintaining and retrieving data packet encapsulation information is key to this convergence approach, exemplified by Layer 3 VPN. Because satellites orbit, links to ground nodes are in a dynamic switching process. If existing routing technology were to be directly used for space-based interconnection, onboard routing would require frequent updates, further impacting the stability of the entire network. Summary of the Invention

[0004] The embodiments of the present invention provide a satellite-to-ground routing establishment method, an electronic device, and a computer program product to at least solve the problem in related technologies that satellites moving along their orbits lead to frequent updates of onboard routing, affecting the stability of the entire network.

[0005] According to one embodiment of the present invention, a method for establishing satellite-to-ground routing is provided, comprising: a satellite's onboard router mapping a time-varying virtual address TV-IP to network information of the ground node according to the connection status of the satellite and the ground node, wherein the TV-IP is used to identify the connection between the satellite and the ground node; and the onboard router updating routing information according to the network information of the ground node.

[0006] According to another embodiment of the present invention, a network device is provided, comprising a receiver, a transmitter and a processor, and configured to execute the steps of any of the above method embodiments through at least one of the receiver, the transmitter and the processor.

[0007] According to yet another embodiment of the present invention, a computer-readable storage medium is provided, in which a computer program is stored. The computer program is configured to execute the steps of any one of the above method embodiments when run.

[0008] According to another embodiment of the present invention, an electronic device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to perform the steps in any one of the above method embodiments.

[0009] According to yet another embodiment of the present invention, a computer program product is provided, including a computer program, which implements the steps of any of the above method embodiments when executed by a processor.

[0010] The above-described embodiments of the present invention provide a method for establishing satellite-to-ground routing. A satellite-based router maps a TV-IP address to the network information of a ground node based on the connection status between the satellite and the ground node. The TV-IP address identifies the connection between the satellite and the ground node. The satellite-based router then updates routing information based on the ground node's network information. This method addresses the problem in related technologies where satellite orbital motion leads to frequent satellite routing updates, impacting overall network stability. The method ensures stable routing between ground nodes and satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a flow chart of a satellite-to-ground routing establishment method according to an embodiment of the present invention;

[0012] Figure 2 is a schematic diagram of route calculation according to an embodiment of the present invention;

[0013] Figure 3 1 is a schematic diagram showing the principle of a routing calculation process for a non-trusted gateway station directly connected to a satellite according to an embodiment of the present invention;

[0014] Figure 4 2 is a schematic diagram of the principle of obtaining a valid source set of TV-IP prefixes according to an embodiment of the present invention;

[0015] Figure 5 2 is a schematic diagram of the principle of determining routing of a gateway station according to an embodiment of the present invention;

[0016] Figure 6This is a schematic diagram of the principle of the route calculation process in a sudden failure scenario according to an embodiment of the present invention;

[0017] Figure 7 This is another schematic diagram of the principle of obtaining a valid source set of TV-IP prefixes according to an embodiment of the present invention;

[0018] Figure 8 FIG. 2 is another schematic diagram of the principle of gateway route determination according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and in combination with embodiments.

[0020] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0021] First, the time-varying virtual address TV-IP in an embodiment of the present invention is introduced. In this embodiment of the present invention, the time-varying virtual address TV-IP is a conceptual network address that can provide a flexible mapping mechanism. Even when the network topology frequently changes, the address direction can be dynamically adjusted through preset rules or routing calculations, thereby maintaining the continuity and efficiency of network communications while reducing the burden of frequent routing table updates on network devices. For example, the TV-IP address of the ground interface of a certain satellite router is: 2001:db8:1a::1 / 64. This TV-IP address is constant in the satellite-to-ground network. Even if the satellite moves in orbit and establishes or disconnects connections with different ground nodes, the TV-IP address will not change. The source of the TV-IP prefix refers to other satellite routers whose link state information containing the TV-IP address can be received by the satellite router through the routing protocol. The ground interface of the onboard router can access 2001:db8:1a::1 / 64, and the announcement containing the link state information of 2001:db8:1a::1 / 64 is sent to other onboard routers except itself. For TV-IP address 2001:db8:1a::1 / 64, the onboard router that announces this TV-IP address is exactly the TV-IP prefix source. In an embodiment of the present invention, the ground interface of the onboard router is a special interface form. This ground interface will be assigned a globally unique TV-IP address, that is, this TV-IP address does not change with the network topology, thereby meeting the requirement of network topology stability. After the interface and routing protocol are configured with corresponding relationship, routing protocol (for example, Open Shortest Path First (OSPF)) will flood this TV-IP address in the form of link state information.

[0022] In this embodiment, a satellite-to-ground routing establishment method is provided. Figure 1 FIG. 1 is a flow chart of a method for establishing satellite-to-ground routing according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0023] In step S102, the satellite's onboard router maps a time-variant IP (TV-IP) to network information of the ground node according to the connection status between the satellite and the ground node, wherein the TV-IP is used to identify the connection between the satellite and the ground node.

[0024] In the embodiment of the present invention, the TV-IP does not change with changes in the network topology, thereby meeting the requirement of network topology stability.

[0025] In an exemplary embodiment, before the onboard router maps the time-varying virtual address TV-IP to the network information of the ground node according to the connection status of the satellite and the ground node, it also includes: the onboard router obtains the ground node information of the ground node, and the ground node information includes at least one of the following: identification information of the ground node; Media Access Control (MAC) address of the ground node's satellite interface; and network information of the ground node.

[0026] In an exemplary embodiment, the network information of the ground node includes at least one of the following: a link local address (linklocal) of the ground node connected to the satellite interface; a loopback address (loopback) of the ground node; and a segment routing location identifier (SR locator) of the ground node.

[0027] In an exemplary embodiment, before the satellite-borne router maps the time-varying virtual address TV-IP to the network information of the ground node according to the connection status of the satellite and the ground node, it also includes: the satellite-borne router announces and receives the TV-IP prefix sources of all TV-IPs through the routing protocol.

[0028] In this embodiment of the present invention, the onboard router uses a routing protocol to notify all onboard routers of the source of the TV-IP prefix for a TV-IP and receives the source of the TV-IP prefix from all onboard routers. If a certain onboard router has no downlink interface or a downlink interface fails, the link status information for the TV-IP corresponding to that interface must be revoked.

[0029] In an exemplary embodiment, the onboard router maps the time-varying virtual address TV-IP to the network information of the ground node based on the connection status between the satellite and the ground node, including: the onboard router obtains the connection status based on the ephemeris information prediction; the onboard router performs routing calculation based on the ephemeris information and the connection status, and maps the TV-IP to the network information of the ground node.

[0030] In an exemplary embodiment, the onboard router performs routing calculation based on the ephemeris information and the connection status, and maps the TV-IP to the network information of the ground node, including: the onboard router identifies the TV-IP; the onboard router performs routing calculation based on the ephemeris information, the connection status and the ground node information of the ground node, and maps the identified TV-IP to the loopback address and / or segment routing location identifier of the ground node.

[0031] In an embodiment of the present invention, the routing calculation process actually includes topology calculation (Shortest Path First (SPF) calculation) and routing calculation (Partial Route Calculation (PRC) calculation). The SPF calculation is implemented based on the shortest path algorithm. After the SPF calculation is completed, the onboard router will identify the reachable IP address prefix information contained in the link state information generated by each routing node and perform PRC calculation. In the PRC calculation process, it is first necessary to identify the TV-IP. If the satellite has a connected ground node, the PRC calculation converts the TV-IP into a real IP prefix that can be provided by the ground node connected to the current satellite-to-ground link, where the real IP prefix is ​​the network information of the ground node; if the satellite does not have a connected ground node, the TV-IP will not be processed.

[0032] Step S104: The onboard router updates routing information according to the network information of the ground node.

[0033] In an exemplary embodiment, before the satellite router updates routing information according to the network information of the ground node, the satellite router further includes: determining the next hop address information of the satellite router according to the path information of the TV-IP prefix source of the TV-IP.

[0034] In this embodiment of the present invention, preconfigured ground node information allows easy identification of the loopback and SR locator corresponding to a specific ground node, and the corresponding route is generated. The next hop of this route inherits the next hop used to reach the original TV-IP address. If multiple satellites are reachable to the same ground node, a preferred route is selected.

[0035] In one exemplary embodiment, the onboard router updates routing information based on network information from a ground node, including: the onboard router updating routing information based on a predicted connection status and network information, wherein the routing information includes at least one of the following: the onboard router's next-hop address information; the onboard router's outbound interface information; the routing path cost; and the optimal routing path. In this embodiment of the present invention, the routing information updated by the onboard router may be a routing information table including the aforementioned information or in another form, without specific limitation herein.

[0036] In an exemplary embodiment, it also includes: when the satellite-to-ground link is interrupted due to the predictable movement of the satellite, the ground interface of the onboard router is set to a specific state other than the link failure or inactive / link normal (down / up) state, and the specific state is not announced to the routing protocol; when the satellite-to-ground link is interrupted and the ground interface is not in a specific state, the ground interface is set to the link failure or inactive (down) state, and the down state is announced to the routing protocol.

[0037] In an exemplary embodiment, a ground node is configured with a static route, the outgoing interface of the static route is a satellite-to-ground link, the static route is planned to a specific network segment of the satellite-borne route, the ground interfaces of all satellites in the specific network segment have the same link-local address and media access control MAC address, and the next-hop address of the static route is the link-local address of the ground interface.

[0038] An embodiment of the present invention provides a method for establishing satellite-to-ground routing. An onboard router maps a TV-IP address (TV-IP) to the network information of a ground node based on the connection status between the satellite and the ground node. The TV-IP address identifies the connection between the satellite and the ground node. The onboard router then updates routing information based on the ground node's network information. This method addresses the problem in related technologies where satellite motion along the track leads to frequent onboard routing updates, impacting overall network stability. The method ensures stable routing between ground nodes and satellites.

[0039] Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus the necessary general hardware platform, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0040] This embodiment also provides a satellite-to-ground routing establishment device for implementing the aforementioned embodiments and preferred implementations. Details already described will not be repeated. As used below, the term "module" may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0041] In the embodiment of the present invention, the satellite-to-ground routing establishment device may further include different modules, wherein the module naming and functional division may also be selected in different ways according to actual conditions, and no specific limitation is made here.

[0042] It should be noted that the above modules can be implemented through software or hardware. For the latter, it can be implemented in the following ways, but not limited to: the above modules are all located in the same processor; or the above modules are located in different processors in any combination.

[0043] An embodiment of the present invention further provides a network device, comprising a receiver, a transmitter, and a processor, and configured to execute the steps of the above-mentioned satellite-to-ground routing establishment method embodiment through at least one of the receiver, the transmitter, and the processor.

[0044] An embodiment of the present invention further provides a computer-readable storage medium, in which a computer program is stored. The computer program is configured to execute the steps of any one of the above method embodiments when running.

[0045] In an exemplary embodiment, the computer-readable storage medium may include, but is not limited to, various media that can store computer programs, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk, or an optical disk.

[0046] An embodiment of the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0047] In an exemplary embodiment, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0048] An embodiment of the present invention further provides a computer program product, including a computer program, which implements the steps of any of the above method embodiments when executed by a processor.

[0049] In an exemplary embodiment, the above-mentioned computer program product includes a non-volatile computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the steps of the method described in each embodiment of the present application are implemented.

[0050] For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail here.

[0051] Obviously, those skilled in the art will appreciate that the various modules or steps of the present invention described above can be implemented using a general-purpose computing device, can be centralized on a single computing device, or can be distributed across a network of multiple computing devices. They can be implemented using program code executable by the computing device, and thus, can be stored in a storage device and executed by the computing device. In some cases, the steps shown or described herein can be performed in a different order than that shown, or can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0052] In order to enable those skilled in the art to better understand the technical solutions of the present invention, they are described below in conjunction with different embodiments.

[0053] Example 1

[0054] In this embodiment of the present invention, a time-varying virtual address (TV-IP) is assigned to each satellite-based router's ground interface. This TV-IP address remains constant despite network topology changes, thereby ensuring network topology stability. During route calculation, this TV-IP address is converted into a real address in the satellite-to-ground network or a ground gateway, in conjunction with ephemeris information. This mapping of the TV-IP address in the network topology with the virtual-to-real address during route calculation not only ensures protocol topology stability but also ensures that routes accurately reflect real network conditions.

[0055] The satellite-to-ground routing establishment method provided in the embodiment of the present invention involves routing establishment of an uplink channel (from a ground node to a satellite) and a downlink channel (from a satellite to a ground node). First, routing establishment of the downlink channel is introduced.

[0056] The routing establishment of the downlink channel includes the following steps:

[0057] S1. Information pre-configuration.

[0058] The following information is preset for each satellite:

[0059] (1) Ground node information: Each satellite is manually pre-configured with the identification information (ID) of all ground nodes, the MAC address of the satellite interface, and the network information of the ground nodes. The network information of the ground nodes includes the link local address of the satellite interface, the loopback address of the ground node, and the segment routing location identifier (SR locator) of the ground node.

[0060] (2) Time-varying virtual address TV-IP.

[0061] S2. The satellite-borne router announces and receives the TV-IP prefix sources of all TV-IPs through the routing protocol.

[0062] The satellite router uses the routing protocol to announce the source of the TV-IP prefix to all satellite routers and receives the source of the TV-IP prefix from all satellite routers. If a satellite router has no downlink interface or a downlink interface fails, the link status information of the TV-IP corresponding to that interface must be revoked.

[0063] A TV-IP prefix source refers to the router in the network that advertises link state information containing a specific TV-IP prefix. In a satellite-to-ground network, this typically refers to an onboard router that can communicate with ground nodes directly or indirectly via inter-satellite links.

[0064] S3. Calculation of TV-IP.

[0065] The routing calculation process of existing routing protocols actually includes topology calculation (SPF calculation) and route calculation (PRC calculation). SPF calculation is implemented based on the shortest path algorithm. After the SPF calculation is completed, the onboard router identifies the reachable IP address prefix information contained in the link state information generated by each routing node and performs the PRC calculation. Figure 2 Schematic diagram of routing calculation according to an embodiment of the present invention. Figure 2 As shown, if the IP address prefix is ​​found to be a TV-IP, subsequent operations are performed based on the current satellite-to-ground link connection status. If the satellite is connected to a ground node, the PRC calculates and converts the TV-IP to a real IP prefix provided by the ground node connected to the current satellite-to-ground link, thereby completing the mapping of the TV-IP to the ground node's network information. The real IP prefix is ​​the ground node's network information. If the satellite is not connected to a ground node, the TV-IP is not processed.

[0066] (1) The next hop is determined.

[0067] Preconfigured ground node information easily identifies the loopback and SR locator corresponding to a given ground node and generates the corresponding route. The satellite router determines the next-hop address of the satellite router based on the path information derived from the TV-IP prefix of the TV-IP. This next-hop address inherits the next-hop address of the original TV-IP. If multiple satellites are reachable to the same ground node, optimal routing is performed.

[0068] (2) Predict network changes to trigger routing calculations.

[0069] The connection status between the satellite and ground nodes is predicted by the on / off and handover changes of the satellite-to-ground link. The prediction results (i.e., the valid source of TV-IP) are notified to the routing protocol (such as OSPF), which triggers the calculation and update of the route.

[0070] S4. Satellite-to-ground link failure notification.

[0071] The onboard router's ground interface is a special interface that senses the satellite's real-time, predictable motion. If the satellite-to-ground link is interrupted due to predictable satellite motion, the interface is placed in a special state other than down / up, and this change is not reported back to the routing protocol. This ensures the stability of the network topology maintained by the routing protocol (for example, the Link State Database (LSDB) in the Interior Gateway Protocol (IGP)).

[0072] If the satellite router's ground interface is not in the special state described above, a satellite-to-ground link interruption is considered a fault, the ground interface is set to down, and the upper-layer routing protocol (such as OSPF) is notified. Upon detecting this change, the upper-layer routing protocol rescinds the link state information corresponding to the TV-IP, triggers route calculation, and notifies neighboring satellite routers. Upon receiving the link state information regarding the TV-IP change, the neighboring satellite routers repeat the route calculation and notification process until all satellite routers in the network have achieved route convergence.

[0073] In the embodiment of the present invention, the uplink channel can be opened by ensuring that the next hop, destination address, and outbound interface remain unchanged and configuring a static route.

[0074] In an embodiment of the present invention, static routing is configured for the ground node, and the ground interfaces of all satellites are configured with the same linklocal and MAC address. The ground node (such as a gateway) is configured with a static network segment route to the connected satellite. The outgoing interface of the static route corresponds to the connection link between the ground node and the satellite, and the next hop corresponds to the linklocal address of the ground interface of the landed satellite. In order to simplify the configuration, the IP of the onboard router can be planned in a specified network segment (i.e., a specific network segment), and the linklocal and MAC addresses of the ground interfaces of each satellite are the same. In this way, static routing can be configured for a small number of reachable network segments, and static routing changes and ND learning caused by frequent switching of satellite-to-ground links can be avoided. The static routing configuration of the embodiment of the present invention is also applicable to IPv4, but due to protocol differences, the linklocal address can be in the form of a borrowed address.

[0075] In addition, in order to determine whether the configured static route is available, the ground node needs to coordinate the configuration of link detection mechanisms such as Ethernet Fault Management (EFM) or Bidirectional Forwarding Detection (BFD). The specific link detection mechanism is not described here.

[0076] Example 2

[0077] The satellite-to-ground routing establishment method provided in the embodiments of the present invention can be applied in scenarios including, but not limited to, routing calculation processes in scenarios with predictable topology changes and sudden failures. For ease of description, the space-based network in this scenario has access and bearer functions, with base stations onboard the satellite; the ground network has core network functions. The ground nodes in this scenario are specifically gateways; the underlay routing protocol for the space-based network is OSPFv3. Furthermore, a single gateway may contain multiple satellite-connected antennas (i.e., available interfaces).

[0078] Figure 3 FIG. 1 is a schematic diagram showing the principle of the routing calculation process for a non-trusted gateway station directly connected to a satellite according to an embodiment of the present invention. Figure 3 As shown, taking Satellite Router 1 (SAT-R1) as an example, the steps include:

[0079] S1. Obtain a set of valid sources of TV-IP prefixes.

[0080] It's important to note that satellites move periodically along fixed orbits, and the longitude and latitude of ground gateways are known. Therefore, based on satellite orbital parameters and publicly available satellite orbit position calculation algorithms, the satellite-to-ground link connectivity, specifically the link's on / off times, can be easily determined. The set of valid TV-IP prefix sources is obtained by receiving TV-IP prefix sources flooded to the current satellite router from other onboard routers. Figure 4 FIG. 1 is a schematic diagram showing the principle of obtaining a valid source set of TV-IP prefixes according to an embodiment of the present invention. Figure 4 As shown, by taking the intersection of the TV-IP prefix source set and the satellite-to-ground prediction link, the TV-IP prefix valid source set is obtained.

[0081] S2, TV-IP mapping gateway station routing.

[0082] Figure 5 FIG. 1 is a schematic diagram showing the principle of determining the routing of a gateway station according to an embodiment of the present invention. Figure 5 As shown, SAT-R1 determines the predicted reachable address (loopback / locator) of the ground node based on the TV-IP prefix valid source set and the pre-configured gateway station list, where the locator includes linklocal and / or SR locator.

[0083] S3. In the existing PRC calculation process, the TV-IP is identified and, combined with the preset ground node network information and the predicted results of the satellite-to-ground link connection, the TV-IP is converted into the routing prefix information that can be provided by the ground node connected to the current satellite-to-ground link. The next hop of the gateway station route locator1 and loopback1 is calculated, where locator1 includes linklocal and / or SR locator.

[0084] Calculate the next hops (SAT-R4, nh1) and (SAT-R6, nh2) to reach the prefix source. Compare the link metrics to determine the optimal next hop. If SAT-R4 is optimal, the forwarding path is SAT-R4 -> SG-T1.

[0085] In an embodiment of the present invention, the route calculation process for a gateway station directly connected to a satellite, taking SAT-R4 as an example, includes the following steps:

[0086] S1. Obtain a set of valid sources of TV-IP prefixes.

[0087] S2, TV-IP mapping gateway station routing.

[0088] S3. Calculate the next hop of the gateway router locator1 and loopback1.

[0089] Calculate the next hops (SAT-R4, nh1) and (SAT-R6, nh2) to reach the prefix source. If the direct next hop is optimal (for example, SAT-R4 determines that it is a directly connected satellite to the ground node), the forwarding path is SAT-R4 -> SG-T1.

[0090] In this embodiment of the present invention, the end-to-end path can be determined based on the routing calculation process for a non-gateway station directly connected to a satellite and the routing calculation process for a gateway station directly connected to a satellite. For example, the forwarding path from SAT-R1 to SG-T1 is: SAT-R1 -> SAT-R3 -> SAT-R4 -> SG-T1.

[0091] Figure 6 FIG. 1 is a schematic diagram of the principle of the routing calculation process under the sudden failure scenario of an embodiment of the present invention. Figure 6 As shown in Figure 1, when the satellite-to-ground link is interrupted due to the predictable periodic motion of the satellite along its orbit, the satellite-to-ground interface is placed in a special state other than down / up. If the satellite-to-ground interface is in the up state but detects a satellite-to-ground link interruption, this link change is identified as a sudden failure, which the protocol must detect and notify of the link status.

[0092] The routing calculation process for a non-gateway station directly connected to a satellite in a sudden failure scenario, taking SAT-R1 as an example, includes the following steps:

[0093] S1. Obtain a set of valid sources of TV-IP prefixes.

[0094] It's important to note that satellites move periodically along fixed orbits, and the longitude and latitude of ground gateways are known. Therefore, based on satellite orbital parameters and publicly available satellite orbit position calculation algorithms, the satellite-to-ground link connectivity, specifically the link's on / off times, can be easily determined. The set of valid TV-IP prefix sources is obtained by receiving TV-IP prefix sources flooded to the current satellite router from other onboard routers. Figure 7 FIG. 1 is another schematic diagram of the principle of obtaining a valid source set of TV-IP prefixes according to an embodiment of the present invention. Figure 7 As shown, by taking the intersection of the TV-IP prefix source set and the satellite-to-ground prediction link, the TV-IP prefix valid source set is obtained.

[0095] S2, TV-IP mapping gateway station routing.

[0096] Figure 8 FIG. 1 is another schematic diagram of the principle of determining the routing of a gateway station according to an embodiment of the present invention. Figure 8 As shown, SAT-R1 determines the reachable address (loopback / locator) of the predicted ground node based on the TV-IP prefix valid source set and the pre-configured gateway station list.

[0097] S3. Calculate the next hop of the gateway router locator1 and loopback1.

[0098] Calculate the next hop (SAT-R6, nh) to reach the prefix source. The forwarding path is: SAT-R1->SAT-R3->SAT-R5->SAT-R6->SG-T1.

[0099] The routing calculation process for a gateway directly connected to a satellite in a sudden failure scenario, using SAT-R6 as an example, includes the following steps:

[0100] S1. Obtain a set of valid sources of TV-IP prefixes.

[0101] S2, TV-IP mapping gateway station routing.

[0102] S3 calculates the next hops for gateway routers locator1 and loopback1. The next hops to the prefix source (SAT-R6, nh) are calculated separately. The direct next hop is optimal, so the forwarding path is SAT-R6 -> SG-T1.

[0103] In this embodiment of the present invention, the end-to-end path can be determined based on the route calculation process for a non-gateway directly connected to a satellite and the route calculation process for a gateway directly connected to a satellite in the sudden failure scenario described above. For example, the forwarding path from SAT-R1 to SG-T1 is: SAT-R1 -> SAT-R3 -> SAT-R5 -> SAT-R6 -> SG-T1.

[0104] In one embodiment, if traffic has already reached SAT-R4 when the link is down, the route calculation process on SAT-R4 is as follows:

[0105] S1. Obtain a set of valid sources of TV-IP prefixes.

[0106] S2, TV-IP mapping gateway station routing.

[0107] S3 calculates the next hops for gateway routers locator1 and loopback1. The next hop to the source prefix (SAT-R6, nh2) is calculated, and the forwarding path is SAT-R4 -> SG-T6.

[0108] In summary, the satellite-to-ground routing establishment method provided by the embodiments of the present invention shields the changes and flooding of link state information caused by frequent satellite-to-ground link switching by introducing TV-IP to the satellite-to-ground interface. It also achieves mapping between virtual addresses and real objects by predicting satellite-to-ground connection relationships. Furthermore, by planning the next hop and destination address corresponding to static routes, it ensures stable routing from ground nodes to satellites. By mapping TV-IP in the network topology and the virtual-to-real relationship during the routing calculation process, the protocol topology is stabilized, ensuring that the routing can accurately reflect the real network conditions.

[0109] During actual implementation, it is possible to determine whether the satellite-to-ground routing establishment method of the embodiment of the present invention has been implemented by obtaining a configuration manual. Based on the configuration commands recorded in the configuration manual, it is determined whether similar address planning methods are adopted for the space-based network and the ground network, including planning the same MAC and LinkLocal for the satellite-to-ground interface; planning the address of a specified network segment for the satellite network portion, etc., and whether to introduce a special interface type that is different from the existing interface. This interface type can shield the impact of predictable satellite-to-ground connection changes on the routing protocol.

[0110] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A satellite-to-ground routing establishment method, characterized in that: include: The satellite's onboard router maps the time-varying virtual address TV-IP to the network information of the ground node according to the connection status between the satellite and the ground node, wherein the TV-IP is used to identify the connection between the satellite and the ground node; The onboard router updates routing information according to the network information of the ground node.

2. The method according to claim 1, characterized in that Before the onboard router maps the time-varying virtual address TV-IP to the network information of the ground node according to the connection status between the satellite and the ground node, the method further includes: The onboard router obtains ground node information of the ground node, where the ground node information includes at least one of the following: The identification information of the ground node; the media access control MAC address of the satellite interface of the ground node; and the network information of the ground node.

3. The method according to claim 2, characterized in that The network information of the ground node includes at least one of the following: The link local address of the ground node connected to the satellite interface; the loopback address of the ground node; and the segment routing location identifier of the ground node.

4. The method according to claim 1, wherein Before the onboard router maps the time-varying virtual address TV-IP to the network information of the ground node according to the connection status between the satellite and the ground node, the method further includes: The onboard router notifies and receives the TV-IP prefix sources of all the TV-IPs through a routing protocol.

5. The method according to claim 1, wherein The onboard router maps the time-varying virtual address TV-IP to the network information of the ground node according to the connection status between the satellite and the ground node, including: The onboard router predicts and obtains the connection status according to the ephemeris information; The onboard router performs routing calculation according to the ephemeris information and the connection status, and maps the TV-IP to the network information of the ground node.

6. The method according to claim 5, characterized in that The onboard router performs routing calculation according to the ephemeris information and the connection status, and maps the TV-IP to the network information of the ground node, including: The onboard router identifies the TV-IP; The onboard router performs routing calculation according to the ephemeris information, the connection status and the ground node information of the ground node, and maps the identified TV-IP to the loopback address and / or segment routing location identifier of the ground node.

7. The method according to claim 1, characterized in that Before the onboard router updates routing information according to the network information of the ground node, the method further includes: The onboard router determines the next hop address information of the onboard router according to the path information of the TV-IP prefix source of the TV-IP.

8. The method according to claim 7, characterized in that The onboard router updates routing information according to the network information of the ground node, including: The onboard router updates the routing information according to the predicted connection status and the network information, wherein: The routing information includes at least one of the following: the next hop address information of the onboard router; the outbound interface information of the onboard router; the routing path cost; and the optimal routing path.

9. The method according to claim 1, characterized in that Also includes: In the case where the satellite-to-ground link is interrupted due to the predictable movement of the satellite, the ground interface of the onboard router is set to a specific state other than link failure or inactive / link normal down / up state, and the specific state is not notified to the routing protocol; When the satellite-to-ground link is interrupted and the ground interface is not in the specific state, the ground interface is set to a link failure or inactivated down state, and the down state is notified to the routing protocol.

10. The method according to claim 1, characterized in that The ground node is configured with a static route, the outgoing interface of the static route is a satellite-to-ground link, the static route is planned to a specific network segment of the satellite-borne route, the ground interfaces of all the satellites in the specific network segment have the same link-local address and media access control MAC address, and the next-hop address of the static route is the link-local address of the ground interface.

11. A network device, characterized in that: The network device comprises a receiver, a transmitter, and a processor, and is configured to execute the steps of the method according to any one of claims 1 to 10 by using at least one of the receiver, the transmitter, and the processor.

12. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, wherein the computer program implements the steps of the method described in any one of claims 1 to 10 when executed by a processor.

13. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 10 are implemented.

14. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 10 are implemented.

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