A communication method, satellite system, electronic equipment and storage medium

Abstract

The present application relates to the field of communication technology, and discloses a communication method, a satellite system, an electronic device, and a storage medium. In the communication method disclosed in the present application, when a first server receives a domain name resolution request sent by a terminal device, if the first IP address corresponding to the first domain name in the domain name resolution request is stored, the first IP address can be directly returned to the terminal device; when the first server does not store the first IP address corresponding to the first domain name, the domain name resolution request is forwarded to a local domain name server through a second server deployed in a geosynchronous satellite, and the first IP address is obtained from the local domain name server through the second server. In this way, satellite communication resources can be effectively saved, and the failure of terminal device network access can be effectively reduced, thereby improving user experience.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method, a satellite system, an electronic device and a storage medium. Background Art

[0002] When a terminal device (such as a mobile phone) accesses the network, for example, when accessing a server corresponding to a domain name, it generally needs to first access a local domain name server (LDNS) to query the Internet Protocol (IP) address corresponding to the domain name, and then access the server corresponding to the domain name according to the IP address. Figure 1 As shown, when the user enters the request Http: / / baab.com / index.abc in the browser application interface 101 of the terminal device 100, the terminal device 100 can send a domain name resolution request carrying the domain name "baab.com" to the LDNS. After receiving the domain name resolution request, the LDNS can obtain the IP address corresponding to the domain name "baab.com" (for example, the IP address is 202.1.201.1) and return the IP address to the terminal device 100. The terminal device 100 accesses the server corresponding to the domain name "baab.com" based on the IP address.

[0003] Among them, the terminal device can establish a communication connection with the LDNS based on a ground network, such as a wireless local area network (WLAN), a fifth generation mobile communication technology (5G) network, etc. to query the IP address corresponding to the domain name.

[0004] With the rapid development of space information technology, non-terrestrial networks (NTN), such as satellite networks, have gradually matured, allowing more network services to be implemented through non-terrestrial networks. For example, the terminal device can also obtain the IP address corresponding to the domain name from the LDNS based on the satellite communication method. When the terminal device accesses the satellite network and needs to query the IP address corresponding to a domain name, it can send a domain name resolution request carrying the domain name to the forwarding server deployed in the satellite through the satellite communication method, and the forwarding server deployed in the satellite sends the domain name resolution request to the LDNS based on the satellite communication method, and obtains the IP address returned by the LDNS. When the forwarding server obtains the IP address corresponding to the domain name, the IP address corresponding to the domain name can be sent to the terminal device. However, in the solution of obtaining the IP address corresponding to the domain name based on the satellite communication method, due to the increasing demand for network access, there will be frequent interactions between the satellite and the ground LDNS, resulting in a serious consumption of satellite communication resources. Summary of the invention

[0005] Embodiments of the present application provide a communication method, a satellite system, an electronic device, and a storage medium.

[0006] In a first aspect, an embodiment of the present application provides a communication method for a satellite system, the satellite system comprising a first server and a second server, the first server being deployed on a first satellite, the first satellite operating in a first earth orbit, the second server being deployed on a second satellite, the second satellite operating in a second earth orbit, the second earth orbit being higher than the first earth orbit; the method comprising: the first server receiving a first domain name resolution request sent by a terminal device in a ground system, the first domain name resolution request comprising a first domain name requested for resolution by the terminal device, the first server storing a mapping relationship between a domain name and an IP address; when the first server determines, based on the mapping relationship between the domain name and the IP address, that the first server does not store a first IP address corresponding to the first domain name, the first server sends the first domain name resolution request to the second server; the second server sends the first domain name resolution request to a local domain name server in the ground system; the second server receives the first IP address corresponding to the first domain name sent by the local domain name server; the second server sends the first IP address to the first server; the first server sends the first IP address to the terminal device.

[0007] It can be understood that when the first server receives the domain name resolution request sent by the terminal device, if the IP address corresponding to the first domain name carried in the domain name resolution request is stored, the IP address corresponding to the first domain name can be directly returned to the terminal device, that is, there is no need to obtain the IP address corresponding to the first domain name from the local domain name server on the ground every time. In this way, the number of interactions between the server on the satellite and the local domain name server on the ground can be reduced, saving satellite communication resources.

[0008] In addition, when the first server does not store the IP address corresponding to the first domain name carried in the domain name resolution request, the domain name resolution request is forwarded to the local domain name server through the second server deployed in the geosynchronous satellite, and the second server obtains the IP address data from the local domain name server based on the satellite-to-ground communication link (or feeder link) between the geosynchronous satellite and the local domain name server. It can be understood that the network coverage of the geosynchronous satellite on the ground is much larger than the network coverage of the low-orbit satellite on the ground, and it runs synchronously with the earth. Therefore, the satellite-to-ground communication link between the local domain name server can basically maintain a real-time connection. Therefore, based on the second server being able to obtain the IP address corresponding to the first domain name in real time, the above-mentioned terminal device network access failure can be effectively reduced, thereby improving the user experience.

[0009] It can be understood that the first server mentioned in the embodiment of the present application can be the secondary server mentioned in the embodiment of the present application, the second server mentioned in the embodiment of the present application can be the primary server mentioned in the embodiment of the present application, and the first domain name mentioned in the embodiment of the present application can refer to the target domain name mentioned in the embodiment of the present application. The first IP address mentioned in the embodiment of the present application can be the IP address corresponding to the target domain name mentioned in the embodiment of the present application. The first satellite mentioned in the embodiment of the present application can be the satellite 200 mentioned in the embodiment of the present application. The second satellite mentioned in the embodiment of the present application can be the satellite 500 mentioned in the embodiment of the present application.

[0010] In a possible implementation of the first aspect, the first server sends a first domain name resolution request to the second server, including: the first server identifies the first domain name resolution request as a first-type domain name resolution request, and sends the first domain name resolution request to the second server.

[0011] In some embodiments, the first server in the first satellite can also classify domain name resolution requests and perform different operations on domain name resolution requests of different types. For the first type of domain name resolution request (for example, a domain name resolution request that needs to access the server corresponding to the first type of application), if the first server in the first satellite does not have the IP address corresponding to the first domain name in the domain name resolution request, the first server in the first satellite forwards the domain name resolution request to the second server in the geosynchronous satellite. For the second type of domain name resolution request (for example, a domain name resolution request that needs to access the server corresponding to the second type of application), if the first server in the first satellite does not have the IP address corresponding to the first domain name in the domain name resolution request, the information that the resolution failed is directly returned to the terminal device, that is, the domain name resolution request will not be forwarded to the second server. In this way, data transmission between the satellite and the ground can be reduced, and the consumption of satellite resources can be reduced.

[0012] In a possible implementation of the first aspect above, the satellite system also includes a user plane function UPF; the first server receives a first domain name resolution request sent by a terminal device in the ground system, including: the user plane function UPF receives a first domain name resolution request sent by a terminal device in the ground system; the user plane function UPF determines that the first domain name resolution request is a first type of domain name resolution request based on the first domain name in the first domain name resolution request, marks a first identifier for the first domain name resolution request, and sends the first domain name resolution request and the first identifier to the first server.

[0013] In a possible implementation of the first aspect above, the user plane function UPF determines that the first domain name resolution request is a first-class domain name resolution request based on the first domain name in the first domain name resolution request, including: the user plane function UPF determines the application corresponding to the first domain name based on the first domain name in the first domain name resolution request, and obtains the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name, and determines that the first domain name resolution request is a first-class domain name resolution request based on the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name; or, the user plane function UPF obtains the user plane forwarding rule information corresponding to the first domain name based on the first domain name in the first domain name resolution request, and determines that the first domain name resolution request is a first-class domain name resolution request based on the user plane forwarding rule information corresponding to the first domain name.

[0014] In some embodiments, UPF 202 can communicate with network elements of the ground core network, such as the policy control function PCF, the session management function SMF, etc., to obtain the subscription information associated with each application, user plane forwarding rule information, etc. from the network elements of the ground core network such as SMF and PCF.

[0015] In a possible implementation of the first aspect above, the first server identifies the first domain name resolution request as a first type of domain name resolution request, including: the first server receives the first domain name resolution request and the first identifier sent by the user plane function UPF, and identifies the first domain name resolution request as a first type of domain name resolution request based on the first identifier.

[0016] In a possible implementation of the first aspect above, the method also includes: the first server receives a second domain name resolution request sent by the terminal device, the second domain name resolution request includes a second domain name requested to be resolved by the terminal device; when the first server determines, based on the mapping relationship between the domain name and the IP address, that the first server does not store the second IP address corresponding to the second domain name, and identifies the second domain name resolution request as a second-type domain name resolution request, it sends a resolution failure message to the terminal device.

[0017] In some embodiments, for the second type of domain name resolution request, if the first server in the first satellite does not have the IP address corresponding to the first domain name in the domain name resolution request, a resolution failure message is directly returned to the terminal device, that is, the domain name resolution request is not forwarded to the second server. In this way, data transmission between the satellite and the ground can be reduced, and the consumption of satellite resources can be reduced.

[0018] In a possible implementation of the first aspect above, the first server receives a second domain name resolution request sent by a terminal device, including: the user plane function UPF receives the second domain name resolution request sent by the terminal device; the user plane function UPF determines that the second domain name resolution request is a second type of domain name resolution request based on the second domain name in the second domain name resolution request, marks the second domain name resolution request with a second identifier, and sends the second domain name resolution request and the second identifier to the first server.

[0019] In a possible implementation of the first aspect above, the satellite system also includes a third server, which is deployed on a third satellite, the third satellite and the first satellite are located in the same constellation, and there is an inter-satellite routing path between the third satellite and the second satellite; the first server sends a first domain name resolution request to the second server, including: the first server determines that there is no inter-satellite routing path between the first satellite and the second satellite, the first server sends the first domain name resolution request to the third server, and the third server sends the first domain name resolution request to the second server.

[0020] It can be understood that the third satellite mentioned in the embodiment of the present application may refer to the satellite 700 mentioned in the embodiment of the present application, and the third server may refer to the first server 701 mentioned in the embodiment of the present application.

[0021] When there is no inter-satellite routing path between the first satellite where the first server is located and the geosynchronous satellite, the first server can send a domain name resolution request to a third server in the third satellite when determining that there is an inter-satellite routing path between the third satellite and the second satellite. The third server forwards the domain name resolution request to the second server. The success rate of the domain name resolution request is ensured, the number of user network access failures is reduced, and the user experience is improved.

[0022] In a possible implementation of the first aspect above, the second server stores a mapping relationship between a domain name and an IP address, and a period at which the second server updates the mapping relationship between the domain name and the IP address from a local domain name server is less than a period at which the first server updates the mapping relationship between the domain name and the IP address from the local domain name server; the second server sends a first domain name resolution request to the local domain name server, including: the second server determines, based on the mapping relationship between the domain name and the IP address stored in the second server, that a first IP address corresponding to the first domain name is not stored in the second server, and sends the first domain name resolution request to the local domain name server.

[0023] In some embodiments, the period of updating the domain name and the IP address corresponding to the domain name from the local domain name server on the ground by the second server in the geosynchronous satellite may be less than the period of updating the domain name and the IP address corresponding to the domain name from the local domain name server on the ground by the first server in the first satellite. In this way, the second server may store more domain names and IP addresses than the first server in some time periods. When the second server in the geosynchronous satellite receives the domain name resolution request sent by the first server, it can be determined whether the second server has the IP address corresponding to the first domain name in the domain name resolution request. If not, the second server establishes a communication connection with the local domain name server on the ground to obtain the IP address corresponding to the first domain name from the local domain name server; if it exists, the IP address corresponding to the first domain name is directly sent to the first server, and the first server sends the IP address corresponding to the first domain name to the terminal device. In this way, the interaction between the server in the satellite and the local domain name server on the ground can be effectively reduced, and the consumption of satellite resources can be reduced.

[0024] In a possible implementation of the first aspect above, the ground system also includes an ephemeris server; the first server sends a first domain name resolution request to the second server, including: the first server sends the first domain name resolution request and identification information of the first satellite to the second server; the second server receives a first IP address corresponding to the first domain name sent by the local domain name server, including: the ephemeris server receives the identification information of the first satellite sent by the local domain name server, and the ephemeris server is used to store the mapping relationship between the satellite identification information and the ephemeris information; the ephemeris server obtains the ephemeris information corresponding to the first satellite based on the identification information of the first satellite; the ephemeris server determines the network coverage ground range information of the first satellite based on the ephemeris information of the first satellite; the ephemeris server sends the network coverage ground range information of the first satellite to the local domain name server; the second server receives the first IP address corresponding to the first domain name sent by the local domain name server, wherein the first IP address is obtained by the local domain name server based on the network coverage ground range information of the first satellite and the mapping relationship between the domain name and the IP address stored in the local domain name server.

[0025] It can be understood that the satellite's network coverage ground range information can represent the approximate location information of the terminal device. The local domain name server on the ground can select the application server corresponding to the first domain name that is closest to the location information of the terminal device from multiple application servers corresponding to the first domain name based on the network coverage ground range information, and send the IP address of the nearest application server as the IP address corresponding to the first domain name to the cache server, so that the access path and delay of the terminal device can be effectively shortened.

[0026] In a possible implementation of the first aspect above, the network coverage ground range information of the first satellite includes: location information of a ground gateway station to which the first satellite is currently connected.

[0027] In a possible implementation of the first aspect above, a method in which a local domain name server obtains a first IP address corresponding to a first domain name based on the network coverage location information of the first satellite and a mapping relationship between domain names and IP addresses stored in the local domain name server includes: the local domain name server determines at least one IP address corresponding to the first domain name based on the mapping relationship between domain names and IP addresses stored in the local domain name server; the local domain name server selects a first IP address from at least one IP address, the first IP address being an IP address corresponding to an application server that is closest to the location information of a ground gateway station.

[0028] In the second aspect, an embodiment of the present application provides a communication method for a satellite system, wherein the satellite system includes a user plane function UPF and a second server, the second server is deployed on a second satellite, the second satellite operates in a second earth orbit, and the second earth orbit is a geosynchronous orbit; the method includes: the user plane function UPF receives a first domain name resolution request sent by a terminal device in a ground system; the first domain name resolution request includes a first domain name requested for resolution by the terminal device; the user plane function UPF determines that the first domain name resolution request is a first type of domain name resolution request based on the first domain name in the first domain name resolution request, and sends the first domain name resolution request to the second server; the second server sends the first domain name resolution request to a local domain name server in the ground system; the second server receives a first IP address corresponding to the first domain name sent by the local domain name server; the second server sends the first IP address to the terminal device.

[0029] In some embodiments, domain name resolution requests are classified by UPF, and second-category domain name resolution requests may not be sent to the second server for processing. In this way, data transmission between geosynchronous satellites and the ground can be reduced, and the consumption of satellite resources can be reduced.

[0030] In a possible implementation of the second aspect above, the satellite system also includes a first server, the first server is deployed on a first satellite, the first satellite operates in a first earth orbit, and the second earth orbit is higher than the first earth orbit; the method also includes: a user plane function UPF receives a second domain name resolution request sent by a terminal device; the user plane function UPF determines that the second domain name resolution request is a second type of domain name resolution request based on the second domain name in the second domain name resolution request, and sends the second domain name resolution request to the first server; when the first server determines that the first server does not store the second IP address corresponding to the second domain name based on the mapping relationship between the domain name and the IP address, the first server sends a resolution failure message to the terminal device; when the first server determines that the first server stores the second IP address corresponding to the second domain name based on the mapping relationship between the domain name and the IP address, the first server sends the second IP address to the terminal device.

[0031] In a possible implementation of the second aspect above, the second server sends the first domain name resolution request to the local domain name server, including: when the second server determines that the second server does not store the IP address corresponding to the first domain name, the second server sends the first domain name resolution request to the local domain name server.

[0032] In a third aspect, an embodiment of the present application provides a satellite system, including: a first server and a second server, wherein the first server is deployed on a first satellite, the first satellite operates in a first earth orbit, and the second server is deployed on a second satellite, the second satellite operates in a second earth orbit, and the second earth orbit is higher than the first earth orbit;

[0033] The first server is used to receive a first domain name resolution request sent by a terminal device in a ground system, the first domain name resolution request includes a first domain name requested for resolution by the terminal device, and the first server stores a mapping relationship between domain names and IP addresses; the first server is used to send the first domain name resolution request to the second server when it is determined, based on the mapping relationship between domain names and IP addresses, that the first server does not store the first IP address corresponding to the first domain name; the second server is used to send the first domain name resolution request to a local domain name server in the ground system, the local domain name server is deployed on the ground; the second server is used to receive the first IP address corresponding to the first domain name sent by the local domain name server; the second server is used to send the first IP address to the first server; the first server is used to send the first IP address to the terminal device, and the first IP address is used for the terminal device to access the application server corresponding to the first domain name.

[0034] In a possible implementation of the third aspect, the first server is configured to send the first domain name resolution request to the second server when identifying the first domain name resolution request as a first type of domain name resolution request.

[0035] In a possible implementation of the third aspect above, the satellite system also includes a user plane function UPF; the user plane function UPF is used to receive a first domain name resolution request sent by a terminal device; the user plane function UPF is used to determine that the first domain name resolution request is a first type of domain name resolution request based on the first domain name in the first domain name resolution request, mark the first domain name resolution request with a first identifier, and send the first domain name resolution request and the first identifier to the first server.

[0036] In a possible implementation of the third aspect above, the user plane function UPF is used to determine the application corresponding to the first domain name based on the first domain name in the first domain name resolution request, and obtain the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name, and determine that the first domain name resolution request is a first-class domain name resolution request based on the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name; or, the user plane function UPF is used to determine the user plane forwarding rule information corresponding to the first domain name based on the first domain name in the first domain name resolution request, and determine that the first domain name resolution request is a first-class domain name resolution request based on the user plane forwarding rule information corresponding to the first domain name.

[0037] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium storing executable instructions, which implement the communication method mentioned in the embodiment of the present application when executed on an electronic device.

[0038] In a fifth aspect, an embodiment of the present application provides an electronic device, comprising: a memory for storing instructions executed by one or more processors of the electronic device, and one or more processors for executing the communication method mentioned in the embodiment of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 According to some embodiments of the present application, a schematic diagram of a browser interface 101 of a terminal device 100 is shown;

[0040] Figure 2a According to some embodiments of the present application, a schematic diagram of a scenario of obtaining an IP address corresponding to a domain name based on satellite communication is shown;

[0041] Figure 2b According to some embodiments of the present application, a schematic flow chart of a method for obtaining an IP address corresponding to a domain name based on satellite communication is shown;

[0042] Figure 3a According to some embodiments of the present application, a schematic diagram of a scenario of obtaining an IP address corresponding to a domain name based on a cache server deployed in a satellite is shown;

[0043] Figure 3bAccording to some embodiments of the present application, a schematic flow chart of a method for obtaining an IP address corresponding to a domain name based on a cache server is shown;

[0044] Figure 4 According to some embodiments of the present application, a schematic diagram of an iterative query method is shown;

[0045] Figure 5a According to some embodiments of the present application, a scenario schematic diagram of a communication method is shown;

[0046] Figure 5b According to some embodiments of the present application, a detailed flow chart of a communication method is shown;

[0047] Figure 6 According to some embodiments of the present application, a scenario schematic diagram of a communication method for determining an IP address based on a geographical range is shown;

[0048] Figure 7 According to some embodiments of the present application, a flow chart of a communication method for performing different operations on different types of domain name resolution requests is shown;

[0049] Figure 8a According to some embodiments of the present application, a schematic diagram of a scenario in which a secondary cache server forwards a domain name resolution request through an auxiliary satellite in a constellation is shown;

[0050] Figure 8b According to some embodiments of the present application, a schematic diagram of a scenario in which a UPF, a gNB, and a secondary cache server are deployed on different satellites is shown;

[0051] Figure 8c According to some embodiments of the present application, based on Figure 8a The scenario shown illustrates a flow diagram of a communication method;

[0052] Fig. 9 According to some embodiments of the present application, a flow chart of a communication method is shown by combining a scenario of forwarding a domain name resolution request through an auxiliary satellite with a scenario of classifying the domain name resolution request;

[0053] Fig.10 According to some embodiments of the present application, a flow chart of a communication method is shown;

[0054] Fig.11 According to some embodiments of the present application, a schematic diagram of the structure of a terminal device is shown;

[0055] Fig.12 According to some embodiments of the present application, a structural diagram of a server is shown. DETAILED DESCRIPTION

[0056] Illustrative embodiments of the present application include, but are not limited to, a communication method, a satellite system, an electronic device, and a storage medium.

[0057] It should be noted that the present application does not limit the specific form of the terminal device. The electronic device may be a mobile phone, a laptop computer, a tablet, a large-screen device, a wearable device (for example, a smart watch, smart glasses, a helmet), a desktop computer, an augmented reality (AR) / virtual reality (VR) device, a personal digital assistant (PDA) and other terminal devices, without limitation herein.

[0058] In order to more clearly understand the solutions in the embodiments of the present application, the terms involved in the present application are first explained.

[0059] DNS: A server that stores the mapping between domain names and IP addresses and is used to convert domain names and IP addresses.

[0060] Uniform resource locator (URL), the unique address of any given resource on the Internet, is used to indicate the server of the Internet host and the specific location of the web page. URL usually contains the protocol (such as HTTP, HTTPS), the domain name (or server name), and the specific path of the resource. For example, for the URL "Http: / / baab.com / index.abc", the protocol is "Http", the domain name is "baab.com", and the specific path of the resource is "index.abc".

[0061] Geosynchronous / geostationary earth orbit (GEO) satellite: A satellite operating in a geosynchronous / geostationary orbit is called a geosynchronous / geostationary orbit satellite. The orbital altitude of a geosynchronous orbit satellite is about 36,000 kilometers. A geosynchronous orbit satellite can provide a large satellite network coverage area. For example, the satellite network provided by a geosynchronous orbit satellite can cover one-third of the world's area, which can be regarded as moving in sync with the earth.

[0062] Medium Earth Orbit (MEO) Satellite: A satellite operating in medium earth orbit, referred to as medium earth orbit satellite. Medium earth orbit is the orbit of artificial satellites located between low earth orbit and geostationary orbit. The operating period of medium earth orbit satellites is generally between 2 and 24 hours.

[0063] Low Earth Orbit (LEO) Satellite: A satellite operating in a low earth orbit, referred to as a low-orbit satellite, operates at an orbital altitude between 300 km and 2000 km, for example, 800 km. The operating speed is greater than the Earth's rotation speed, the network coverage area is small, and the data transmission delay between the satellite and the ground equipment is small.

[0064] Next generation nodeB (gNB): can be called a 5G base station, which is used to realize the connection between the terminal device and the 5G core network. For example, it is used to route the data sent by the terminal device to the data sending network element in the 5G core network, such as the user plane function (UPF).

[0065] UPF: A network element of the 5G core network used to implement data routing and forwarding. For example, it is used to receive data sent by the gNB and forward the data to the corresponding server.

[0066] Feeder link: A link used to describe a satellite communication system. Feeder links are used to transmit data between ground gateway stations and satellites. The terminal equipment on the ground establishes a connection with the satellite in space through the service link. At the same time, the satellite communicates with the ground gateway through the feeder link. The ground gateway is generally also called a ground station or ground gateway station. The ground gateway station is responsible for routing the data of the terminal equipment to the telephone, TV network or Internet on the ground.

[0067] Figure 2a A schematic diagram of a scenario for obtaining an IP address corresponding to a domain name based on satellite communication is shown.

[0068] like Figure 2aAs shown, when the terminal device 100 needs to query the IP address corresponding to the target domain name, if the terminal device 100 is connected to the satellite network, the domain name resolution request can be sent to the forwarding server 301 in the low-orbit satellite 300 through the gNB 201 and UPF 202 in the low-orbit satellite 200. The forwarding server 301 sends the domain name resolution request to the ground LDNS 400 based on the ground gateway station 003, and obtains the IP address corresponding to the target domain name carried in the domain name resolution request from the LDNS 400, and sends the IP address corresponding to the target domain name to the terminal device 100 through the gNB 201 and UPF 202 in the low-orbit satellite 200. After receiving the IP address corresponding to the target domain name, the terminal device 100 initiates a transmission control protocol (TCP) connection to the application server 001 corresponding to the IP address based on the IP address to achieve network access. It can be understood that the application server 001 can update its own IP address and domain name to the LDNS 400.

[0069] Figure 2b based on Figure 2a The scenario shown in FIG. 1 illustrates a method flow chart of obtaining an IP address corresponding to a domain name based on satellite communication. Figure 2b As shown, the method includes:

[0070] 1001: The terminal device 100 sends a domain name resolution request to the gNB 201 in the low-orbit satellite 200.

[0071] It can be understood that when the terminal device 100 needs to query the IP address corresponding to the target domain name, if the terminal device 100 is connected to the satellite network, a domain name resolution request carrying the target domain name can be sent through the satellite network to the gNB 201 in the low-orbit satellite 200. In some embodiments, the domain name resolution request can carry the target domain name.

[0072] 1002: gNB 201 sends a domain name resolution request to UPF 202 in the low-orbit satellite 200.

[0073] It can be understood that when gNB 201 receives a domain name resolution request, it can route the domain name resolution request to UPF 202 in the low-orbit satellite 200 based on the satellite network.

[0074] 1003: UPF 202 sends a domain name resolution request to the forwarding storage server 301 in the low-orbit satellite 300.

[0075] In some embodiments, when receiving a domain name resolution request, UPF 202 can find the target low-orbit satellite according to a preconfigured satellite selection and scheduling strategy, for example, selecting the low-orbit satellite 300 that is closest to the low-orbit satellite 200 where UPF 202 is located as the target low-orbit satellite, and sending the domain name resolution request to the forwarding storage server 301 in the low-orbit satellite 300 based on the satellite network.

[0076] 1004: The forwarding storage server 301 in the low-orbit satellite 300 sends a domain name resolution request to the LDNS 400 on the ground.

[0077] It can be understood that when receiving the domain name resolution request, the forwarding storage server 301 can forward the domain name resolution request to the LDNS 400 on the ground, so as to obtain the IP address corresponding to the target domain name from the LDNS 400 on the ground.

[0078] 1005: LDNS 400 obtains the IP address corresponding to the target domain name based on the domain name resolution request.

[0079] In some embodiments, when receiving a domain name resolution request, LDNS 400 may query an IP address corresponding to the target domain name from a data system based on the target domain name carried in the domain name resolution request.

[0080] 1006 : LDNS 400 sends the IP address corresponding to the target domain name to the forwarding server 301 .

[0081] In some embodiments, after obtaining the IP address corresponding to the target domain name, the LDNS 400 may send the IP address corresponding to the target domain name to the forwarding server 301 .

[0082] 1007: The forwarding server 301 sends the IP address corresponding to the target domain name to the UPF 202.

[0083] In some embodiments, the forwarding server 301 receives the IP address corresponding to the target domain name and can send the IP address corresponding to the target domain name to the UPF 202.

[0084] 1008: UPF 202 sends the IP address corresponding to the target domain name to gNB 201.

[0085] In some embodiments, UPF 202 receives the IP address corresponding to the target domain name and can send the IP address corresponding to the target domain name to gNB 201.

[0086] 1009: gNB 201 sends the IP address corresponding to the target domain name to the terminal device 100.

[0087] In some embodiments, gNB 201 receives the IP address corresponding to the target domain name and can send the IP address corresponding to the target domain name to the terminal device 100.

[0088] 1010: The terminal device 100 accesses the corresponding application server 001 based on the IP address.

[0089] In some embodiments, after receiving the IP address corresponding to the target domain name, the terminal device 100 can access the corresponding application server 001 based on the IP address.

[0090] In some embodiments, the method for the terminal device 100 to access the corresponding application server 001 based on the IP address is that the terminal device 100 sends an access request carrying the IP address to the gNB 201, and after receiving the access request, the gNB 201 sends the access request to the UPF 202, and after receiving the access request, the UPF 202 sends the access request to the ground gateway station 004, and the ground gateway station 004 sends the access request to the corresponding application server 001.

[0091] Access the corresponding application server 001 based on the IP address carried in the access request.

[0092] It can be understood that in the above method, each time the forwarding server 301 deployed in the satellite 300 receives a domain name resolution request sent by the terminal device, it needs to forward the domain name resolution request to the LDNS 400 on the ground, obtain the IP address corresponding to the target domain name from the LDNS 400, and then return the IP address corresponding to the target domain name to the terminal device 100. In this way, due to the increasing demand for network access, the number of domain name resolution requests that the forwarding server 301 needs to forward is relatively large, resulting in frequent interactions between the forwarding server 301 and the LDNS 400 on the ground, resulting in serious consumption of satellite communication resources.

[0093] To solve the above problems, in some implementation schemes, a cache server is deployed in the satellite to obtain the IP address corresponding to the domain name. Among them, the cache server can update the domain name and the IP address corresponding to the domain name from the ground LDNS 400 according to a preset period (for example, every 1 hour) and cache it. In this way, when the cache server receives the domain name resolution request sent by the terminal device, if the IP address corresponding to the target domain name carried in the domain name resolution request is stored, the IP address corresponding to the target domain name can be directly returned to the terminal device, that is, there is no need to obtain the IP address corresponding to the target domain name from the ground LDNS every time. In this way, the number of interactions between the cache server and the ground LDNS can be reduced, saving satellite communication resources.

[0094] Figure 3aThe schematic diagram shows a scenario of obtaining the IP address corresponding to a domain name based on a cache server deployed in a satellite. Figure 3a As shown, when the terminal device 100 needs to query the IP address corresponding to the target domain name, if the terminal device 100 is connected to the satellite network, the domain name resolution request can be sent to the cache server 302 in the low-orbit satellite 300 through the gNB 201 and UPF 202 in the low-orbit satellite 200. When the cache server 302 caches the IP address corresponding to the target domain name, the IP address corresponding to the target domain name can be sent to the terminal device 100. When the cache server 302 does not cache the IP address corresponding to the target domain name, it will send a domain name resolution request to the ground LDNS 400 based on the ground gateway station 0031, and obtain the IP address corresponding to the target domain name returned by the LDNS 400, and send the obtained IP address corresponding to the target domain name to the terminal device 100. After receiving the IP address corresponding to the target domain name, the terminal device 100 accesses the corresponding application server based on the IP address. It can be understood that the application server 001 can update its own IP address and domain name to the LDNS 400.

[0095] It can be understood that the cache server 302 caches the mapping relationship between the domain name and the IP address, and when the cache server 302 does not store the IP address corresponding to the target domain name requested for resolution by the terminal device, it can send the domain name resolution request to the ground LDNS 400 based on the ground gateway station 0031. That is, in addition to the forwarding function of the forwarding server 301, the cache server 302 also has a cache function.

[0096] Figure 3b based on Figure 3a The scenario shown in FIG. 1 illustrates a method flow chart of obtaining the IP address corresponding to a domain name based on a cache server. Figure 3b As shown, the method includes:

[0097] 2001: The terminal device 100 sends a domain name resolution request to the gNB 201 in the low-orbit satellite 200.

[0098] It can be understood that when the terminal device 100 needs to query the IP address corresponding to the target domain name, if the terminal device 100 is connected to the satellite network, a domain name resolution request carrying the target domain name can be sent through the satellite network to the gNB 201 in the low-orbit satellite 200. In some embodiments, the domain name resolution request can carry the target domain name.

[0099] 2002: gNB 201 sends a domain name resolution request to UPF 202 in the low-orbit satellite 200.

[0100] It can be understood that when gNB 201 receives a domain name resolution request, it can route the domain name resolution request to UPF 202 in the low-orbit satellite 200 based on the satellite network.

[0101] 2003: UPF 202 sends a domain name resolution request to the cache server 302 in the low-orbit satellite 300.

[0102] In some embodiments, when receiving a domain name resolution request, UPF 202 can find the target low-orbit satellite according to a preconfigured satellite selection and scheduling strategy, for example, selecting the low-orbit satellite 300 that is closest to the low-orbit satellite 200 where UPF 202 is located as the target low-orbit satellite, and sending the domain name resolution request to the cache server 302 in the low-orbit satellite 300 based on the satellite network.

[0103] 2004: The cache server 302 determines whether the IP address corresponding to the target domain name is cached.

[0104] In some embodiments, after receiving the domain name resolution request, the cache server 302 may determine whether the IP address corresponding to the target domain name is cached in the cache server 302. When the cache server 302 caches the IP address corresponding to the target domain name, the process proceeds to 2005, and the IP address corresponding to the target domain name may be sent to the UPF 202.

[0105] If the cache server 302 does not cache the IP address corresponding to the target domain name, for example, it has not yet updated the latest domain name and IP address from LDNS 400, resulting in the IP address corresponding to the target domain name not being cached, then go to 2008, send a domain name resolution request to the LDNS 400 on the ground, and obtain the IP address corresponding to the target domain name returned by LDNS 400.

[0106] 2005: The cache server 302 sends the IP address corresponding to the target domain name to the UPF 202.

[0107] In some embodiments, when the cache server 302 caches the IP address corresponding to the target domain name, the IP address corresponding to the target domain name can be sent to the UPF 202 .

[0108] In some embodiments, when the cache server 302 receives the IP address corresponding to the target domain name sent by the LDNS 400, it can send the IP address corresponding to the target domain name to the UPF 202.

[0109] 2006: UPF 202 sends the IP address corresponding to the target domain name to gNB 201.

[0110] In some embodiments, UPF 202 receives the IP address corresponding to the target domain name and can send the IP address corresponding to the target domain name to gNB 201.

[0111] 2007: gNB 201 sends the IP address corresponding to the target domain name to the terminal device 100.

[0112] In some embodiments, gNB 201 receives the IP address corresponding to the target domain name and can send the IP address corresponding to the target domain name to the terminal device 100.

[0113] 2008: The terminal device 100 accesses the corresponding application server 001 based on the IP address.

[0114] In some embodiments, after receiving the IP address corresponding to the target domain name, the terminal device 100 can access the corresponding application server 001 based on the IP address. In some embodiments, the terminal device 100 can access the corresponding application server 001 based on the IP address by sending an access request carrying the IP address to the gNB 201, and after receiving the access request, the gNB 201 sends the access request to the UPF 202, and after receiving the access request, the UPF 202 sends the access request to the ground gateway station 004, and the ground gateway station 004 sends the access request to the corresponding application server 001.

[0115] 2009: The cache server 302 sends a domain name resolution request to the LDNS 400 on the ground.

[0116] In some embodiments, if the cache server 301 does not cache the IP address corresponding to the target domain name, for example, it has not yet updated the latest domain name and IP address from the LDNS 400, resulting in the IP address corresponding to the target domain name not being cached, a domain name resolution request is sent to the LDNS 400 on the ground.

[0117] 2010: LDNS 400 obtains the IP address corresponding to the target domain name based on the domain name resolution request.

[0118] In some embodiments, when receiving a domain name resolution request, LDNS 400 may query an IP address corresponding to the target domain name from a data system based on the target domain name carried in the domain name resolution request.

[0119] 2011: LDNS 400 sends the IP address corresponding to the target domain name to the cache server 302.

[0120] It is understandable that when LDNS 400 queries the IP address corresponding to the target domain name from the data system, it can send the IP address corresponding to the target domain name to cache server 302, so that cache server 302 sends the IP address corresponding to the target domain name to terminal device 100 based on steps 2005 to 2007.

[0121] In some embodiments, when the LDNS 400 determines that the IP address of the target domain name is cached in the LDNS 400 , the LDNS 400 may send the IP address of the target domain name cached in the LDNS 400 to the cache server 302 .

[0122] In some embodiments, when the LDNS 400 determines that the IP address of the target domain name is not cached in the LDNS 400 , the LDNS 400 may perform an iterative query to obtain the IP address of the target domain name.

[0123] The schematic diagram of iterative query can be as follows Figure 4 As shown in , LDNS 400 sends a domain name resolution request to a root domain name server 401, and the root domain name server 401 returns the IP address of the top-level domain name server 402 corresponding to the suffix (such as .com, etc.) of the target domain name carried in the domain name query request to LDNS 400. Based on the received IP address of the top-level domain name server 402, LDNS 400 sends a domain name resolution request to the corresponding top-level domain name server 402. When the IP address of the target domain name is stored in the top-level domain name server 402, the IP address of the target domain name is sent to LDNS 400.

[0124] If the top-level domain name server 402 does not store the IP address of the target domain name, the IP address of the authoritative domain name server 403 is sent to the LDNS 400. The LDNS 400 sends a domain name resolution request to the authoritative domain name server 403 based on the IP address of the authoritative domain name server 403, and the authoritative domain name server 403 sends the IP address of the target domain name to the LDNS 400.

[0125] It can be understood that the domain name resolution request transmitted by the terminal device 100 to the LDNS 400 through the cache server 302 can be regarded as a recursive query. After receiving the recursive query, the LDNS 400 can perform a recursive query if the IP address of the target domain name is not cached. Figure 4 The iterative query shown in is performed, and the query result, i.e., the IP address corresponding to the target domain name, is sent to the terminal device 100.

[0126] In some embodiments, when UPF 202 sends a domain name resolution request to cache server 302, it may also send identification information of satellite 200 where UPF 202 is located. When cache server 302 sends a domain name resolution request to LDNS 400, it carries identification information of satellite 200 where UPF 202 is located.

[0127] When receiving the domain name resolution request and the identification information of the low-orbit satellite 200, the ground LDNS 400 can also send the identification information of the low-orbit satellite 200 to the application server discovery function (application server discovery function) server (or called ephemeris server) to obtain the network coverage ground range information of the low-orbit satellite 200 where the UPF 202 is located at this time, wherein the network coverage ground range information of the low-orbit satellite 200 at this time may include the location information of the ground gateway station 004 connected to the low-orbit satellite 200 at this time. Among them, the application server discovery function server can be authorized and trusted by the operator or controlled by the operator, and the application server discovery function server can be configured with a mapping relationship between ephemeris information (such as satellite trajectory information, etc.) and satellite identification information. When receiving the satellite identification information of the low-orbit satellite 200, the application server discovery function server 600 can obtain the ephemeris information of the low-orbit satellite 200, and determine the network coverage ground range information of the satellite 200 at this time based on the ephemeris information, such as the location information of the ground gateway station connected to the low-orbit satellite at this time. And send the network coverage ground range information to the ground LDNS 400. It can be understood that the network coverage ground range information of the satellite 200 can represent the approximate location information of the terminal device 100.

[0128] The ground LDNS 400 can select the application server corresponding to the target domain name that is closest to the location information of the ground gateway station 004 connected at this time in the low-orbit satellite 200 based on the network coverage ground range information from multiple application servers corresponding to the target domain name, and send the IP address of the nearest application server as the IP address corresponding to the target domain name to the cache server 302. In this way, the access path and delay of the terminal device 100 can be effectively shortened.

[0129] It can be understood that LDNS 400 is used to implement domain name resolution requests of terminal devices within a preset range. For example, a corresponding LDNS can be deployed in the C city area to implement domain name resolution requests sent by terminal devices in the C city area. Figure 3a and Figure 3b The terminal device 100 mentioned in is located in the C city area, then the cache server 302 will send the domain name resolution request sent by the terminal device 100 to the LDNS in the C city area.

[0130] In summary, in the method for obtaining the IP address corresponding to the target domain name based on the cache server, when the cache server caches the IP address corresponding to the target domain name carried in the domain name resolution request sent by the terminal device, the IP address corresponding to the target domain name can be directly returned to the terminal device, that is, there is no need to obtain the IP address corresponding to the target domain name from the ground LDNS every time. In this way, the number of interactions between the cache server and the ground LDNS can be reduced, saving satellite communication resources.

[0131] However, since the network coverage of low-orbit satellites is relatively small and low-orbit satellites are constantly orbiting the earth, when the LDNS to be accessed by the terminal device is outside the network coverage of the low-orbit satellite, the cache server deployed on the low-orbit satellite cannot communicate with the LDNS. As a result, in some cases, the cache server will not be able to obtain the IP address corresponding to the target domain name from the LDNS, resulting in the failure of terminal device network access and affecting the user experience.

[0132] For example, if Figure 3b The terminal device 100 sending the domain name resolution request mentioned in the above is located in the urban area C, and the network coverage of the low-orbit satellite 300 is in the urban area D which is far away from the urban area C. At this time, the cache server 302 on the low-orbit satellite 300 will not be able to communicate with the LDNS 400 in the urban area C. If the cache server 302 does not cache the IP address corresponding to the target domain name in the domain name resolution request sent by the terminal device 100, the cache server 302 will not be able to obtain the IP address corresponding to the target domain name from the LDNS 400, resulting in a network access failure of the terminal device 100, affecting the user experience.

[0133] In order to solve the above problems, the present application implements a communication method, which can deploy servers in both low-orbit satellites and geosynchronous satellites. For example, a secondary server is deployed in a low-orbit satellite, and a primary server is deployed in a geosynchronous satellite. When the secondary server in the low-orbit satellite receives a domain name resolution request sent by a terminal device, if the secondary server in the low-orbit satellite does not have the IP address corresponding to the target domain name in the domain name resolution request, the secondary server in the low-orbit satellite forwards the domain name resolution request to the primary server in the geosynchronous satellite, and the primary server in the geosynchronous satellite establishes a communication connection with the LDNS on the ground to obtain the IP address corresponding to the target domain name from the LDNS. It can be understood that the network coverage of the geosynchronous satellite on the ground is much larger than the network coverage of the low-orbit satellite on the ground, and it runs synchronously with the earth, so the satellite-to-ground communication link with the LDNS can basically maintain a real-time connection. Therefore, the IP address data can be obtained from the LDNS in real time through the geosynchronous satellite, thereby effectively reducing the above-mentioned terminal device network access failure and improving the user experience.

[0134] It should be noted that when the primary server is deployed on a geosynchronous satellite, the secondary server in the embodiment of the present application may also be deployed on a low-orbit satellite or a medium-orbit satellite. In some embodiments, when the secondary server is deployed on a low-orbit satellite, the primary server may also be deployed on a medium-orbit satellite. The following text uses the secondary server deployed on a low-orbit satellite and the primary server deployed on a geosynchronous satellite for exemplary description.

[0135] In some embodiments, both the secondary server in the low-orbit satellite and the primary server in the geosynchronous satellite may cache the mapping relationship between the domain name and the IP address.

[0136] In some embodiments, the domain name and IP address information cached by the secondary server in the low-orbit satellite and the primary server in the geosynchronous satellite are consistent. When the primary server in the geosynchronous satellite receives the domain name resolution request sent by the secondary server, the primary server in the geosynchronous satellite forwards the domain name resolution request to the LDNS on the ground to obtain the IP address corresponding to the target domain name from the LDNS.

[0137] In some embodiments, the primary server in the geosynchronous satellite and the secondary server in the low-orbit satellite can update the domain name and the IP address corresponding to the domain name from the ground LDNS at the same preset period (for example, every 1 hour) and cache them. It can be understood that the preset period can be set according to actual needs, and the specific value of the preset period is not limited in this application.

[0138] In some embodiments, the period for the primary server in the geosynchronous satellite to update the domain name and the IP address corresponding to the domain name from the LDNS on the ground may be shorter than the period for the secondary server in the low-orbit satellite to update the domain name and the IP address corresponding to the domain name from the LDNS on the ground. In this way, the primary server may store more domain names and IP addresses than the secondary server in some time periods. When the primary server in the geosynchronous satellite receives the domain name resolution request sent by the secondary server, it can be determined whether the IP address corresponding to the target domain name in the domain name resolution request exists in the primary server. If not, the primary server establishes a communication connection with the LDNS on the ground to obtain the IP address corresponding to the target domain name from the LDNS; if it exists, the IP address corresponding to the target domain name is directly sent to the secondary server, and the secondary server sends the IP address corresponding to the target domain name to the terminal device.

[0139] In some embodiments, the primary server in the geosynchronous satellite may not cache the mapping relationship between the domain name and the IP address. When the primary server in the geosynchronous satellite receives the domain name resolution request sent by the secondary server, the primary server in the geosynchronous satellite forwards the domain name resolution request to the LDNS on the ground to obtain the IP address corresponding to the target domain name from the LDNS.

[0140] It can be understood that when the secondary server receives the domain name resolution request sent by the terminal device, if the IP address corresponding to the target domain name carried in the domain name resolution request is stored, the IP address corresponding to the target domain name can be directly returned to the terminal device, that is, there is no need to obtain the IP address corresponding to the target domain name from the ground LDNS every time. In this way, the number of interactions between the cache server and the ground LDNS can be reduced, saving satellite communication resources.

[0141] In addition, when the secondary server does not store the IP address corresponding to the target domain name carried in the domain name resolution request, the domain name resolution request is forwarded to the LDNS through the primary server deployed in the geosynchronous satellite, and the primary server obtains the IP address data from the LDNS based on the satellite-to-ground communication link (or feeder link) between the geosynchronous satellite and the LDNS. It can be understood that the network coverage of the geosynchronous satellite on the ground is much larger than the network coverage of the low-orbit satellite on the ground, and it runs synchronously with the earth, so the satellite-to-ground communication link with the LDNS can basically maintain a real-time connection. Therefore, based on the ability of the primary server to obtain the IP address corresponding to the target domain name in real time, it can effectively reduce the above-mentioned terminal device network access failures and improve the user experience.

[0142] It should be noted that in the embodiment of the present application, the first-level server can establish a communication connection with the ground LDNS through the ground gateway station when the feeder link between the satellite where the first-level server is located and the ground gateway station is valid (that is, can communicate normally).

[0143] The communication method mentioned in the embodiments of the present application is described in detail below.

[0144] It should be noted that the secondary server 203 mentioned in the embodiment of the present application can be used as an example of the first server in the embodiment of the present application, the primary server 501 mentioned in the embodiment of the present application can be used as an example of the second server in the embodiment of the present application, and the secondary server 701 mentioned in the embodiment of the present application can be used as an example of the third server in the embodiment of the present application.

[0145] Figure 5a A schematic diagram of a communication method is shown. Figure 5aAs shown, when the terminal device 100 needs to query the IP address corresponding to the target domain name, if the terminal device 100 is connected to the satellite network, the domain name resolution request can be sent to the secondary server 203 in the low-orbit satellite 200 through the gNB 201 and UPF 202 in the low-orbit satellite 200. When the secondary server 203 caches the IP address corresponding to the target domain name, the IP address corresponding to the target domain name can be sent to the terminal device 100. When the secondary server 203 does not cache the IP address corresponding to the target domain name, the domain name resolution request is forwarded to the primary server 501 in the geosynchronous satellite 500, and the primary server 501 in the geosynchronous satellite 500 establishes a communication connection with the ground LDNS 400 based on the ground gateway station 0032 to obtain the IP address corresponding to the target domain name from the ground LDNS 400, and sends the obtained IP address corresponding to the target domain name to the terminal device 100. After receiving the IP address corresponding to the target domain name, the terminal device 100 accesses the corresponding application server 001 based on the IP address. It can be understood that the application server 001 can update its own IP address and domain name to the LDNS 400 .

[0146] It can be understood that the satellite network of geosynchronous satellites has a large coverage area and runs synchronously with the earth. Therefore, the satellite-to-ground communication link with LDNS can basically maintain a real-time connection. Therefore, the IP address data in LDNS can be obtained in real time through geosynchronous satellites, which can effectively reduce the above-mentioned domain name resolution failures and improve the success rate of domain name resolution, that is, reduce the failure of user network access and improve user experience.

[0147] Figure 5b based on Figure 5a The scenario shown in FIG. 1 illustrates a flow chart of a communication method. Figure 5b As shown, the method includes:

[0148] 3001: The terminal device 100 sends a domain name resolution request to the gNB 201 in the low-orbit satellite 200.

[0149] It can be understood that when the terminal device 100 detects a network request input by the user, it can determine that the IP address corresponding to the target domain name carried in the network request needs to be queried. If the terminal device 100 is connected to a satellite network, a domain name resolution request carrying the target domain name can be sent through the satellite network to the gNB 201 in the low-orbit satellite 200.

[0150] In some embodiments, the domain name resolution request may carry the target domain name. Figure 1As shown, when the user enters a network request of Http: / / baab.com / index.abc in the browser application interface 101 of the terminal device 100, the terminal device can send a domain name resolution request carrying the target domain name "baab.com" to the LDNS.

[0151] In some embodiments, the terminal device 100 can be configured to automatically obtain the IP address of the server on the satellite to be accessed when using the satellite network. For example, the terminal device can be manually configured or configured to automatically obtain the IP address of the secondary server 203 of the low-orbit satellite 200.

[0152] In some embodiments, when the terminal device 100 sends a domain name resolution request to the gNB 201 in the low-orbit satellite 200, it can also send the IP address of the secondary server 203 in the above-mentioned low-orbit satellite 200.

[0153] It should be noted that the domain name resolution request mentioned in the embodiments of the present application can also be called a DNS request, a DNS resolution request, a DNS query request, etc., and this application does not limit this.

[0154] 3002: gNB 201 sends a domain name resolution request to UPF 202 in the low-orbit satellite 200.

[0155] It can be understood that when gNB 201 receives the domain name resolution request and the IP address of the secondary server 203, it can route the IP address of the secondary server 203 and the domain name resolution request to the UPF 202 in the low-orbit satellite.

[0156] 3003: UPF 202 sends a domain name resolution request to the secondary server 203.

[0157] In some embodiments, when UPF 202 receives the domain name resolution request sent by gNB 201 and the IP address of the secondary server 203, it can send a domain name resolution request to the secondary server 203 based on the IP address of the secondary server 203.

[0158] 3004: The secondary server 203 determines whether the IP address corresponding to the target domain name is cached.

[0159] In some embodiments, when receiving the domain name resolution request, the secondary server 203 may determine whether the IP address corresponding to the target domain name is cached in the secondary server 203. When the server 203 caches the IP address corresponding to the target domain name, the process proceeds to 3010, and the IP address corresponding to the target domain name may be sent to the UPF 202.

[0160] If the server 203 does not cache the IP address corresponding to the target domain name, the domain name resolution request can be sent to the target primary server in the geosynchronous satellite. In the embodiment of the present application, the target primary server is the primary server 501 in the geosynchronous satellite 500 as an example for description.

[0161] In some embodiments, the secondary server 203 may be pre-configured with one or more IP addresses of the primary server. When the secondary server is configured with an IP address of a primary server, the primary server corresponding to the IP address of the primary server is directly used as the target primary server, and a domain name resolution request is sent to the target primary server based on the IP address of the target primary server. When the secondary server 203 is pre-configured with the IP addresses of multiple primary servers, the target primary server may be selected based on the inter-satellite routing strategy, for example, a primary server in the geosynchronous satellite closest to the current low-orbit satellite 200 is selected as the target primary server. The IP address of the target primary server is obtained, and a domain name resolution request is sent to the target primary server based on the IP address of the target primary server.

[0162] 3005: The secondary server 203 sends a domain name resolution request to the primary server 501.

[0163] In some embodiments, when the secondary server 203 determines that the server 301 does not cache the IP address corresponding to the target domain name, it sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500 .

[0164] 3006: The primary server 501 sends a domain name resolution request to the LDNS 400 on the ground.

[0165] In some embodiments, after receiving the domain name resolution request, the primary server 501 may send the domain name resolution request to the LDNS 400 on the ground.

[0166] In some embodiments, both the secondary server 203 and the primary server 501 may cache the mapping relationship between the domain name and the IP address.

[0167] In some embodiments, the domain name and IP address information cached by the secondary server 203 and the primary server 501 are consistent. When the primary server 501 receives the domain name resolution request sent by the secondary server 203, the primary server 501 forwards the domain name resolution request to the ground LDNS 400 to obtain the IP address corresponding to the target domain name from the LDNS 400.

[0168] In some embodiments, the primary server 501 and the secondary server 203 can both update the domain name and the IP address corresponding to the domain name from the ground LDNS 400 at the same preset period (for example, every 1 hour) and cache them. It can be understood that the preset period can be set according to actual needs, and the specific value of the preset period is not limited in this application.

[0169] In some embodiments, the period for the primary server 501 to update the domain name and the IP address corresponding to the domain name from the ground LDNS 400 may be shorter than the period for the secondary server 203 to update the domain name and the IP address corresponding to the domain name from the ground LDNS 400. In this way, the primary server 501 may store more domain names and IP addresses than the secondary server 203. When the primary server 501 receives the domain name resolution request sent by the secondary server 203, it can be determined whether the IP address corresponding to the target domain name in the domain name resolution request exists in the primary server 501. If not, the primary server 501 establishes a communication connection with the ground LDNS 400 to obtain the IP address corresponding to the target domain name from the LDNS 400; if it exists, the IP address corresponding to the target domain name is directly sent to the secondary server 203, and the secondary server 203 sends the IP address corresponding to the target domain name to the terminal device.

[0170] In some embodiments, the primary server 501 may not cache the mapping relationship between the domain name and the IP address. When the primary server 501 receives the domain name resolution request sent by the secondary server 203, the primary server 501 forwards the domain name resolution request to the ground LDNS 400 to obtain the IP address corresponding to the target domain name from the LDNS 400.

[0171] It can be understood that the ground coverage area of ​​the satellite network of satellite 500 is greater than the ground coverage area of ​​the satellite network of satellite 200.

[0172] 3007: LDNS 400 obtains the IP address corresponding to the target domain name based on the domain name resolution request.

[0173] In some embodiments, when LDNS 400 obtains a domain name resolution request, it may query the IP address of the target domain name carried in the domain name resolution request.

[0174] In some embodiments, when the LDNS 400 determines that the IP address of the target domain name is cached in the LDNS 400 , the LDNS 400 may send the IP address of the target domain name cached in the LDNS 400 to the primary server 501 .

[0175] In some embodiments, when LDNS 400 determines that the IP address of the target domain name is not cached in LDNS 400, the aforementioned Figure 4The mentioned iterative query is to obtain the IP address of the target domain name.

[0176] It can be understood that in some embodiments, there may be multiple IP addresses of the server corresponding to the target domain name. For example, when the terminal device 100 detects the user's operation of opening application A, or opening a page in application A, it can detect a network request to access the server of application A, and there may be multiple servers corresponding to application A, for example, there are multiple servers corresponding to application A deployed in urban area C. Then there will be multiple IP addresses of the server corresponding to application A.

[0177] Therefore, in some embodiments, when UPF 202 sends a domain name resolution request to the secondary server 203, it can also send the identification information of the satellite 200 where UPF 202 is located. When the secondary server 203 sends a domain name resolution request to the primary server 501, it carries the identification information of the satellite 200 where UPF 202 is located; when the primary server 203 sends a domain name resolution request to the LDNS 400, it carries the identification information of the satellite 200 where UPF 202 is located.

[0178] like Figure 6 As shown, when the ground LDNS 400 receives the domain name resolution request and the identification information of the low-orbit satellite 200, it can also send the identification information of the low-orbit satellite 200 to the application server discovery function server (or called the ephemeris server) 600 to obtain the network coverage ground range information of the low-orbit satellite 200 where the UPF 202 is located at this time, wherein the network coverage ground range information of the low-orbit satellite 200 at this time may include the location information of the ground gateway station 004 connected to the low-orbit satellite 200 at this time. Among them, the application server discovery function server 600 can be authorized and trusted by the operator or controlled by the operator, and the application server discovery function server 600 can be configured with a mapping relationship between ephemeris information (such as satellite trajectory information, etc.) and satellite identification information. When the application server discovery function server 600 receives the satellite identification information of the low-orbit satellite 200, it can obtain the ephemeris information of the low-orbit satellite 200, and determine the network coverage ground range information of the satellite 200 at this time based on the ephemeris information, such as the location information of the ground gateway station connected to the low-orbit satellite at this time. The network coverage ground range information is sent to the ground LDNS 400. It can be understood that the network coverage ground range information of the satellite 200 can represent the approximate location information of the terminal device 100.

[0179] The ground LDNS 400 can select the application server corresponding to the target domain name that is closest to the location information of the ground gateway station 004 connected to the low-orbit satellite 200 based on the network coverage ground range information from multiple application servers corresponding to the target domain name, and send the IP address of the nearest application server as the IP address corresponding to the target domain name to the primary server 501. In this way, the access path and delay of the terminal device 100 can be effectively shortened.

[0180] 3008: LDNS 400 sends the IP address corresponding to the target domain name to the primary server 501.

[0181] In some embodiments, upon receiving the IP address corresponding to the target domain name, the LDNS 400 may send the IP address corresponding to the target domain name to the primary server 501 .

[0182] 3009: The primary server 501 sends the IP address corresponding to the target domain name to the secondary server 203.

[0183] In some embodiments, upon receiving the IP address corresponding to the target domain name, the primary server 501 may send the IP address corresponding to the target domain name to the secondary server 203 .

[0184] 3010: The secondary server 203 sends the IP address corresponding to the target domain name to the UPF 202.

[0185] In some embodiments, when the secondary server 203 caches the IP address corresponding to the target domain name, the IP address corresponding to the target domain name can be sent to the UPF 202.

[0186] In some embodiments, when the secondary server 203 receives the IP address corresponding to the target domain name sent by the primary server 501, it can send the IP address corresponding to the target domain name to the UPF 202.

[0187] 3011: UPF 202 sends the IP address corresponding to the target domain name to gNB 201.

[0188] In some embodiments, UPF 202 receives the IP address corresponding to the target domain name and can send the IP address corresponding to the target domain name to gNB 201.

[0189] 3012: gNB 201 sends the IP address corresponding to the target domain name to the terminal device 100.

[0190] In some embodiments, gNB 201 receives the IP address corresponding to the target domain name and can send the IP address corresponding to the target domain name to the terminal device 100.

[0191] 3013: The terminal device 100 accesses the corresponding application server 001 based on the IP address.

[0192] In some embodiments, after receiving the IP address corresponding to the target domain name, the terminal device 100 can access the corresponding application server (AS) 001 based on the IP address. It should be noted that the application server mentioned in the embodiments of the present application can also be called an application function (AF).

[0193] In some embodiments, the method for the terminal device 100 to access the corresponding application server 001 based on the IP address is that the terminal device 100 sends an access request carrying the IP address to the gNB 201, and after receiving the access request, the gNB 201 sends the access request to the UPF 202, and after receiving the access request, the UPF 202 sends the access request to the ground gateway station 004, and the ground gateway station 004 sends the access request to the corresponding application server 001.

[0194] In summary, based on Figure 5a and 5b In the communication method shown, if the secondary server in the low-orbit satellite does not have the IP address corresponding to the target domain name in the domain name resolution request, the secondary server in the low-orbit satellite forwards the domain name resolution request to the primary server in the geosynchronous satellite, and the primary server in the geosynchronous satellite establishes a communication connection with the LDNS on the ground to obtain the IP address corresponding to the target domain name from the LDNS. It can be understood that the satellite network of the geosynchronous satellite has a large coverage area and runs synchronously with the earth, so the satellite-to-ground communication link with the LDNS can basically maintain a real-time feed connection. Therefore, the IP address data in the LDNS can be obtained in real time through the geosynchronous satellite, thereby effectively improving the resolution success rate and reliability of the domain name resolution request, reducing the above-mentioned terminal device network access failures, and improving the user experience.

[0195] In addition, based on Figure 5a and 5b The communication method shown can select the application server corresponding to the target domain name closest to the geographical coverage range of the low-orbit satellite 200 based on the access satellite of the terminal device, such as the network coverage location information of the above-mentioned low-orbit satellite 200, and send the IP address of the nearest application server as the IP address corresponding to the target domain name to the terminal device. In this way, the access path and delay of the terminal device can be effectively shortened.

[0196] In some embodiments, the secondary server in the low-orbit satellite can also classify domain name resolution requests and perform different operations on different types of domain name resolution requests. For the first type of domain name resolution request (for example, a domain name resolution request that needs to access the server corresponding to the first type of application), if the secondary server in the low-orbit satellite does not have the IP address corresponding to the target domain name in the domain name resolution request, the secondary server in the low-orbit satellite forwards the domain name resolution request to the primary server in the geosynchronous satellite. For the second type of domain name resolution request (for example, a domain name resolution request that needs to access the server corresponding to the second type of application), if the secondary server in the low-orbit satellite does not have the IP address corresponding to the target domain name in the domain name resolution request, the resolution failure information is directly returned to the terminal device, that is, the domain name resolution request will not be forwarded to the primary server in the geosynchronous satellite. In this way, the data transmission between the geosynchronous satellite and the ground can be reduced, and the consumption of satellite resources can be reduced.

[0197] Figure 7 Take the example of a secondary server in a low-orbit satellite performing different operations on different types of domain name resolution requests. Figure 7 As shown, the method includes:

[0198] 4001: The terminal device 100 sends a domain name resolution request to the gNB 201 in the low-orbit satellite 200.

[0199] 4002: gNB 201 sends a domain name resolution request to UPF 202 in the low-orbit satellite 200.

[0200] It should be noted that the contents of 4001-4002 are similar to those of 3001-3002, and will not be elaborated herein in the embodiment of the present application.

[0201] 4003: UPF 202 sends a domain name resolution request to the secondary server 203.

[0202] In some embodiments, when UPF 202 receives the domain name resolution request sent by gNB 201 and the IP address of the secondary server 203, it can send a domain name resolution request to the secondary server 203 based on the IP address of the secondary server 203.

[0203] In some embodiments, when receiving a domain name resolution request from the terminal device 100, the UPF 202 may also determine the application that sends the domain name resolution request based on the target domain name. It can be understood that the server name corresponding to the domain name is the name of the application server corresponding to the application. Therefore, the application that sends the domain name resolution request can be determined based on the server name corresponding to the domain name, or is referred to as the application corresponding to the target domain name.

[0204] Then, UPF 202 determines the category of the application based on the subscription information associated with the application and / or the user plane diversion rule, and marks different identifiers for the domain name resolution request based on the category of the application. UPF 202 can send the domain name resolution request and the corresponding identifier to the secondary server 203.

[0205] For example, when UPF202 receives the domain name resolution request sent by gNB 201, it identifies the domain name in the domain name resolution request, matches and executes the user plane diversion rule / N4 session rule, which can also be understood as a rule detection on the domain name resolution request data packet, that is, UPF202 obtains the application contract information and / or user plane forwarding rule information. UPF202 can determine the category of the application based on the application contract data and / or user plane forwarding rule information, and mark different identifiers for the domain name resolution request.

[0206] For example, when the application is determined to be a first type of application based on the contract information and / or user-plane forwarding rule information associated with the application, the domain name resolution request is determined to be a first type of domain name resolution request, and the domain name resolution request is marked with a first identifier; when the application is determined to be a second type of application based on the contract information and / or user-plane forwarding rule information associated with the application, the domain name resolution request is determined to be a second type of domain name resolution request, and the domain name resolution request is marked with a second identifier; when the application is determined to be a third type of application based on the contract information and / or user-plane forwarding rule information associated with the application, the domain name resolution request is determined to be a third type of domain name resolution request, then domain name resolution is not performed on the domain name resolution request, and resolution failure information is directly returned to the terminal device 100.

[0207] Among them, the first category of applications may be applications associated with the first category of contract information and / or the first category of user-plane forwarding rule information, and the first category of contract information and / or the first category of user-plane forwarding rule information represent that the service provider of the first category of applications has signed a first agreement with the network operator. The second category of applications may be applications associated with the second category of contract information and / or the second category of user-plane forwarding rule information, and the second category of contract information and / or the second category of user-plane forwarding rule information represent that the service provider of the application has signed a second agreement with the network operator. The third category of applications may be applications that are not associated with contract information and / or user-plane forwarding rule information, for example, the service provider of the application has not signed an agreement with the network operator, and the application is not allowed to use the DNS resolution service at this time.

[0208] In some embodiments, UPF202 may also determine the user plane forwarding rule information corresponding to the domain name based on the domain name in the domain name resolution request, and determine the category of the domain name resolution request based on the user plane forwarding rule information corresponding to the domain name. That is, the domain name and the user plane forwarding rule information have a corresponding association. For example, when it is determined that the user plane forwarding rule information corresponding to the domain name is the first type of user plane forwarding rule information, the domain name resolution request is determined to be the first type of domain name resolution request, and when it is determined that the user plane forwarding rule information corresponding to the domain name is the second type of user plane forwarding rule information, the domain name resolution request is determined to be the second type of domain name resolution request.

[0209] In some embodiments, UPF 202 can be used to communicate with network elements of the ground core network, such as policy control function (PCF), session management function (SMF), etc., so as to obtain the subscription information associated with each application, user plane forwarding rule information, etc. from network elements of the ground core network such as SMF and PCF.

[0210] It should be noted that the above classification method is only an example, and this application does not limit the classification method of domain name resolution requests.

[0211] 4004: The secondary server 203 determines whether the IP address corresponding to the target domain name is cached.

[0212] In some embodiments, when receiving the domain name resolution request, the secondary server 203 may determine whether the IP address corresponding to the target domain name is cached in the secondary server 203. When the secondary server 203 caches the IP address corresponding to the target domain name, the process proceeds to 4010, and the IP address corresponding to the target domain name may be sent to the UPF 202.

[0213] In some embodiments, if the secondary server 203 does not cache the IP address corresponding to the target domain name, the process may go to 40051, where the secondary server 203 determines whether the domain name resolution request is a first-class domain name resolution request.

[0214] In some embodiments, the secondary server 203 and the primary server 501 may update the domain name and the IP address corresponding to the domain name from the ground LDNS 400 at a preset period (eg, every hour) and cache them.

[0215] 40051: The secondary server 203 determines whether the domain name resolution request is a first-type domain name resolution request.

[0216] If the secondary server 203 determines that the domain name resolution request is a first-class domain name resolution request, it means that a domain name resolution request needs to be sent to the primary server 501 , then go to 4005 , and the secondary server 203 sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500 .

[0217] If the secondary server 203 determines that the domain name resolution request is a second-class domain name resolution request, it means that there is no need to send a domain name resolution request to the primary server 501, then the process goes to 40052 and sends a resolution failure message to the UPF 202, so that the UPF 202 sends the resolution failure message to the terminal device. The resolution failure message may include the reason for the resolution failure, such as the secondary server 203 being unable to resolve the request. In some embodiments, the reason for the resolution failure may also be in the form of an identifier, a character, a numerical value, etc.

[0218] For example, when the identifier corresponding to the domain name resolution request is a first-class identifier, the secondary server 203 determines whether the domain name resolution request is a first-class domain name resolution request and determines that the domain name resolution request is a first-class domain name resolution request. For the first-class domain name resolution request, the secondary server 203 forwards the domain name resolution request to the primary server 501 in the geosynchronous satellite 500. When the identifier corresponding to the domain name resolution request is a second-class identifier, the domain name resolution request is determined to be a second-class domain name resolution request. For the second-class domain name resolution request, the resolution failure information is directly returned to the terminal device 100, that is, the domain name resolution request will not be forwarded to the primary server 501 in the orbiting satellite 500. In this way, the data transmission between the geosynchronous satellite and the ground can be reduced, and the consumption of satellite resources can be reduced.

[0219] It should be noted that the resolution failure information mentioned in the embodiments of the present application can also be called DNS resolution failure response, DNS query failure response, DNS resolution response, DNS query response, etc., which is not limited by the embodiments of the present application.

[0220] 40052: The secondary server 203 sends a parsing failure message to the UPF 202.

[0221] 40053: UPF 202 sends parsing failure information to gNB 201.

[0222] In some embodiments, when UPF 202 receives the parsing failure information, it can send the parsing failure information to gNB 201.

[0223] 40054: gNB 201 sends parsing failure information to the terminal device 100.

[0224] In some embodiments, when gNB 201 receives the parsing failure information, it can send the parsing failure information to the terminal device 100.

[0225] It should be noted that steps 4005-4013 are similar to steps 3005-3013 and will not be repeated below.

[0226] 4005: The secondary server 203 sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500.

[0227] 4006: The primary server 501 sends a domain name resolution request to the LDNS 400 on the ground.

[0228] 4007: LDNS 400 obtains the IP address corresponding to the target domain name based on the domain name resolution request.

[0229] 4008: LDNS 400 sends the IP address corresponding to the target domain name to the primary server 501.

[0230] 4009: The primary server 501 sends the IP address corresponding to the target domain name to the secondary server 203.

[0231] 4010: The secondary server 203 sends the IP address corresponding to the target domain name to the UPF 202.

[0232] 4011: UPF 202 sends the IP address corresponding to the target domain name to gNB 201.

[0233] 4012: gNB 201 sends the IP address corresponding to the target domain name to the terminal device 100.

[0234] 4013: The terminal device 100 accesses the corresponding application server 001 based on the IP address.

[0235] In summary, based on Figure 7 The communication method shown can reduce data transmission between geosynchronous satellites and the ground and reduce the consumption of satellite resources by classifying domain name resolution requests.

[0236] Understandably, based on Figure 7 The communication method shown is to determine whether the domain name resolution request is sent to the primary server 501 by the secondary server 203. In some embodiments, the determination of whether the domain name resolution request is sent to the primary server 501 may also be made by the UPF 202.

[0237] That is, when receiving the domain name resolution request, UPF 202 can directly send the domain name resolution request to the primary server 501 when it is determined that the domain name resolution request is a first-class domain name resolution request based on the classification method for the domain name resolution request in step 4003, and when the domain name resolution request is a second-class domain name resolution request, the domain name resolution request is sent to the secondary server 203. When the secondary server 203 receives the domain name resolution request, if it is determined that the secondary server 203 does not have the IP address corresponding to the target domain name in the domain name resolution request, it directly returns the resolution failure information to the terminal device 100 based on UPF 202 and gNB 201; if it is determined that the secondary server 203 has the IP address corresponding to the target domain name in the domain name resolution request, it directly returns the IP address corresponding to the target domain name to the terminal device 100 based on UPF 202 and gNB 201.

[0238] It can be understood that the domain name and IP address can be stored in the primary server 501. When the primary server 501 receives the domain name resolution request sent by the UPF 202, it can be determined whether the IP address corresponding to the target domain name in the domain name resolution request exists in the primary server 501. If not, the primary server 203 establishes a communication connection with the ground LDNS 400 to obtain the IP address corresponding to the target domain name from the LDNS 400; if it exists, the IP address corresponding to the target domain name is directly sent to the terminal device 100 based on the UPF 202 and the gNB 201.

[0239] In some embodiments, the primary server 501 may not cache the mapping relationship between the domain name and the IP address. When the primary server 501 receives the domain name resolution request, it forwards the domain name resolution request to the ground LDNS 400 to obtain the IP address corresponding to the target domain name from the LDNS 400, and sends the IP address corresponding to the target domain name to the terminal device 100 based on the UPF 202 and the gNB 201.

[0240] In some embodiments, when there is no inter-satellite routing path between the low-orbit satellite 200 where the secondary server 203 is located and the geosynchronous satellite 500, that is, the secondary server 203 cannot directly establish a communication connection with the primary server. The secondary server 203 can query the auxiliary satellite in the constellation where the low-orbit satellite 200 is located that has an inter-satellite path with the geosynchronous satellite 500, and forward the domain name resolution request to the primary server 501 in the geosynchronous satellite 500 through the auxiliary satellite.

[0241] Figure 8a A schematic diagram of a scenario in which a secondary server 203 forwards a domain name resolution request to a primary server 501 via an auxiliary satellite 700 in a constellation 002 is shown. Figure 8aAs shown, when there is no inter-satellite routing path between the low-orbit satellite 200 where the secondary server 203 is located and the geosynchronous satellite 300, the secondary server 203 can send a domain name resolution request to the secondary server 701 in the satellite 700 when determining that there is an inter-satellite routing path between the satellite 700 (auxiliary satellite) and the geosynchronous satellite 300. The secondary server 701 forwards the domain name resolution request to the primary server 501 in the geosynchronous satellite 500.

[0242] In some embodiments, Figure 8b As shown, UPF 202, gNB 201 and secondary server 203 may also be deployed on different satellites. For example, UPF 202, gNB 201 are deployed on low-orbit satellite 200, and secondary server 203 is deployed on low-orbit satellite 200-1. This application does not limit this.

[0243] Figure 8c based on Figure 8a The scenario shown in FIG. 1 illustrates a flow chart of a communication method. Figure 8c As shown, the method includes:

[0244] 5001: The terminal device 100 sends a domain name resolution request to the gNB 201 in the low-orbit satellite 200.

[0245] 5002: gNB 201 sends a domain name resolution request to UPF 202 in the low-orbit satellite 200.

[0246] 5003: UPF 202 sends a domain name resolution request to the secondary server 203.

[0247] 5004: The secondary server 203 determines whether the IP address corresponding to the target domain name is cached.

[0248] It should be noted that steps 5001-5004 may refer to steps 3001-3004, or may refer to steps 4001-4004, and will not be repeated here.

[0249] 50051: The secondary server 203 determines whether there is a routing path between the secondary server 203 and the primary server 501 in the geosynchronous satellite 500.

[0250] In some embodiments, if the secondary server 203 determines that there is a routing path between the secondary server 203 and the primary server 501 in the geosynchronous satellite 500 , it goes to 5005 , and the secondary server 203 sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500 .

[0251] In some embodiments, if the secondary server 203 determines that there is no routing path between the secondary server 203 and the primary server 501 in the geosynchronous satellite 500, it goes to 50052, and the secondary server 203 obtains the secondary server 701 that has a routing path with the primary server 501 in the geosynchronous satellite 500.

[0252] It can be understood that when the secondary server 203 determines that there is an inter-satellite routing path between the satellite 200 and the satellite 500, it is determined that there is a routing path between the secondary server 203 in the satellite 200 and the primary server 501 in the satellite 500, that is, the secondary server 203 and the primary server 501 can communicate. When the secondary server 203 determines that there is no inter-satellite routing path between the satellite 200 and the satellite 500, it is determined that there is no routing path between the secondary server 203 in the satellite 200 and the primary server 501 in the satellite 500, that is, the secondary server 203 and the primary server 501 cannot communicate.

[0253] 50052: The secondary server 203 obtains the secondary server 701 which has a routing path with the primary server 501 in the geosynchronous satellite 500.

[0254] In some embodiments, the secondary server 203 may sequentially send link query requests to other satellites in the constellation 002 (e.g., processors in other satellites), and the link query requests may carry identification information of the satellite 500. The satellite that receives the link query request may query whether there is an intersatellite routing path between the satellite 500 and the satellite 500. If there is, a presence response is returned to the secondary server 203. If not, a non-existence response is returned to the secondary server 203. When the secondary server 203 receives the presence response for the first time, for example, when receiving the presence response sent by the satellite 700, it stops sending link query requests to other satellites. And a domain name resolution request is sent to the secondary server 203 in the satellite 700.

[0255] It can be understood that there are inter-satellite links (ISLs), that is, inter-satellite routing paths, between satellites belonging to the same constellation. Different constellations have at least one inter-satellite link to ensure that satellites in different constellations can communicate with each other.

[0256] 50053: The secondary server 203 sends a domain name resolution request to the secondary server 701.

[0257] 50054: The secondary server 701 sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500.

[0258] In some embodiments, upon receiving a domain name resolution request, the secondary server 701 sends the domain name resolution request to the primary server 501 in the geosynchronous satellite 500 .

[0259] It should be noted that steps 5005-5013 can refer to steps 3005-3013 and will not be repeated here.

[0260] 5005: The secondary server 203 sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500.

[0261] 5006: The primary server 501 sends a domain name resolution request to the LDNS 400 on the ground.

[0262] 5007: LDNS 400 obtains the IP address corresponding to the target domain name based on the domain name resolution request.

[0263] 5008: LDNS 400 sends the IP address corresponding to the target domain name to the primary server 501.

[0264] 5009: The primary server 501 sends the IP address corresponding to the target domain name to the secondary server 203.

[0265] In some embodiments, when there is no routing path between the primary server 501 and the secondary server 203 , the primary server 501 sends the IP address corresponding to the target domain name to the secondary server 701 , and the secondary server 701 sends the IP address corresponding to the target domain name to the secondary server 203 .

[0266] In some embodiments, when a routing path exists between the primary server 501 and the secondary server 203, the primary server 501 sends the IP address corresponding to the target domain name to the secondary server 203 through the routing path.

[0267] 5010: The secondary server 203 sends the IP address corresponding to the target domain name to the UPF 202.

[0268] 5011: UPF 202 sends the IP address corresponding to the target domain name to gNB 201.

[0269] 5012: gNB 201 sends the IP address corresponding to the target domain name to the terminal device 100.

[0270] 5013: The terminal device 100 accesses the corresponding application server 001 based on the IP address.

[0271] In summary, based on Figure 8a and Figure 8bIn the communication method shown, when there is no inter-satellite routing path between the low-orbit satellite 200 where the secondary server 203 is located and the geosynchronous satellite 500, the secondary server 203 can send a domain name resolution request to the server 701 in the satellite 700 when determining that there is an inter-satellite routing path between the satellite 700 and the geosynchronous satellite 500. The server 701 forwards the domain name resolution request to the primary server 501 in the geosynchronous satellite 500. The success rate of the domain name resolution request is guaranteed, the number of user network access failures is reduced, and the user experience is improved.

[0272] In summary, based on the communication method in the embodiment of the present application, if the secondary server in the low-orbit satellite does not have the IP address corresponding to the target domain name in the domain name resolution request, the secondary server in the low-orbit satellite forwards the domain name resolution request to the primary server in the geosynchronous satellite, and the primary server in the geosynchronous satellite establishes a communication connection with the LDNS on the ground to obtain the IP address corresponding to the target domain name from the LDNS. It can be understood that the satellite network coverage area of ​​the geosynchronous satellite is large and runs synchronously with the earth, so the satellite-to-ground communication link with the LDNS can basically maintain a real-time feed connection. Therefore, the IP address data in the LDNS can be obtained in real time through the geosynchronous satellite, thereby effectively improving the resolution success rate and reliability of the domain name resolution request, reducing the above-mentioned terminal device network access failures, and improving the user experience.

[0273] In addition, based on the communication method in the embodiment of the present application, the application server corresponding to the target domain name closest to the coverage geographical range of the low-orbit satellite 200 can be selected based on the access satellite of the terminal device, such as the network coverage location information of the above-mentioned low-orbit satellite 200, and the IP address of the nearest application server can be sent to the terminal device as the IP address corresponding to the target domain name. In this way, the access path and delay of the terminal device can be effectively shortened.

[0274] In addition, based on the communication method in the embodiment of the present application, by classifying domain name resolution requests, data transmission between geosynchronous satellites and the ground can be reduced, thereby reducing the consumption of satellite resources.

[0275] Fig. 9 based on Figure 8a The scenario of forwarding domain name resolution requests through auxiliary satellites combined with the scenario of classifying domain name resolution requests is a flow chart of a communication method. Fig. 9 As shown, the method includes:

[0276] 6001: The terminal device 100 sends a domain name resolution request to the gNB 201 in the low-orbit satellite 200.

[0277] 6002: gNB 201 sends a domain name resolution request to UPF 202 in the low-orbit satellite 200.

[0278] 6003: UPF 202 sends a domain name resolution request to the secondary server 203.

[0279] 6004: The secondary server 203 determines whether the IP address corresponding to the target domain name is cached.

[0280] 60051: The secondary server 203 determines whether the domain name resolution request is a first-type domain name resolution request.

[0281] 60052: The secondary server 203 sends a parsing failure message to the UPF 202.

[0282] 60053: UPF 202 sends parsing failure information to gNB 201.

[0283] 60054: gNB 201 sends parsing failure information to the terminal device 100.

[0284] It should be noted that steps 6001-60054 can refer to steps 4001-40054 and will not be repeated here.

[0285] 60055: The secondary server 203 determines whether there is a routing path between the secondary server 203 and the primary server 501 in the geosynchronous satellite 500.

[0286] 60056: The secondary server 203 obtains the secondary server 701 which has a routing path with the primary server 501 in the geosynchronous satellite 500.

[0287] 60057: The secondary server 203 sends a domain name resolution request to the secondary server 701.

[0288] 60058: The secondary server 701 sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500.

[0289] 6005: The secondary server 203 sends a domain name resolution request to the primary server 501 in the geosynchronous satellite 500.

[0290] 6006: The primary server 501 sends a domain name resolution request to the LDNS 400 on the ground.

[0291] 6007: LDNS 400 obtains the IP address corresponding to the target domain name based on the domain name resolution request.

[0292] 6008: LDNS 400 sends the IP address corresponding to the target domain name to the primary server 501.

[0293] 6009: The primary server 501 sends the IP address corresponding to the target domain name to the secondary server 203.

[0294] 6010: The secondary server 203 sends the IP address corresponding to the target domain name to the UPF 202.

[0295] 6011: UPF 202 sends the IP address corresponding to the target domain name to gNB 201.

[0296] 6012: gNB 201 sends the IP address corresponding to the target domain name to the terminal device 100.

[0297] 6013: The terminal device 100 accesses the corresponding application server 001 based on the IP address.

[0298] It should be noted that steps 60055-6013 can refer to steps 50051-5013 and will not be repeated here.

[0299] Fig.10 A flow chart of a communication method according to an embodiment of the present application is shown. Fig.10 As shown, the communication method includes:

[0300] 7001: The terminal device sends a domain name resolution request corresponding to the first domain name to the first server.

[0301] In some embodiments, the first server is deployed on a first satellite, the first satellite operates in a first earth orbit, the domain name resolution request includes a first domain name, and the first server stores a mapping relationship between the domain name and the IP address.

[0302] The first server may be the secondary server 203 mentioned in the embodiment of the present application. The first satellite may refer to the low-orbit satellite 200 or the low-orbit satellite 200-1 mentioned in the embodiment of the present application.

[0303] In some embodiments, the manner in which the terminal device sends a domain name resolution request corresponding to the first domain name to the first server may refer to steps 3001-3003, or steps 5001-5003.

[0304] 7002: The first server determines whether the IP address corresponding to the first domain name is stored.

[0305] In some embodiments, the first server may determine whether the IP address corresponding to the first domain name is stored based on the correspondence between the domain name and the IP address stored in the first server. The first server may determine whether the IP address corresponding to the first domain name is stored by referring to step 3004.

[0306] If the first server determines that the IP address corresponding to the target domain name is stored, the process goes to 7008, and the second server sends the first IP address to the terminal device.

[0307] If the first server determines that the IP address corresponding to the target domain name is not stored, the process goes to 7003, and the first server sends a domain name resolution request to the second server.

[0308] In some embodiments, the second server may be the secondary server 203 mentioned in the embodiments of the present application.

[0309] 7003: The first server sends a domain name resolution request to the second server.

[0310] The second server is deployed on a second satellite, the second satellite operates in a second earth orbit, and the second earth orbit is higher than the first earth orbit;

[0311] In some embodiments, the second satellite may be the satellite 500 mentioned in the embodiment of the present application, and the second earth orbit may be the high earth orbit mentioned in the embodiment of the present application. The satellite network of the second satellite covers a larger area of ​​the ground than the satellite network of the first satellite.

[0312] In some embodiments, the manner in which the first server sends a domain name resolution request to the second server may refer to steps 3005, 50051-5005, and 40051-4005.

[0313] 7004: The second server sends a domain name resolution request to the local domain name server.

[0314] In some embodiments, the manner in which the second server sends a domain name resolution request to the local domain name server can be seen in step 3006.

[0315] In some embodiments, the local domain name server may be the LDNS 400 mentioned in the embodiments of the present application.

[0316] 7005: The local domain name server obtains the first IP address corresponding to the first domain name based on the domain name resolution request.

[0317] In some embodiments, the manner in which the local domain name server obtains the first IP address corresponding to the first domain name based on the domain name resolution request can be seen in step 3007.

[0318] 7006: The local domain name server sends the first IP address to the second server.

[0319] In some embodiments, the manner in which the local domain name server sends the first IP address to the second server can be seen in 3008.

[0320] 7007: The second server sends the first IP address to the first server.

[0321] 7008: The first server sends the first IP address to the terminal device.

[0322] In some embodiments, the manner in which the second server sends the first IP address to the terminal device can be seen in 3009-3012, 5008-5012.

[0323] In summary, based on the communication method in the embodiment of the present application, if the secondary server in the low-orbit satellite does not have the IP address corresponding to the target domain name in the domain name resolution request, the secondary server in the low-orbit satellite forwards the domain name resolution request to the primary server in the geosynchronous satellite, and the primary server in the geosynchronous satellite establishes a communication connection with the LDNS on the ground to obtain the IP address corresponding to the target domain name from the LDNS. It can be understood that the satellite network coverage area of ​​the geosynchronous satellite is large and runs synchronously with the earth, so the satellite-to-ground communication link with the LDNS can basically maintain a real-time feeder connection. Therefore, the IP address data in the LDNS can be obtained in real time through the geosynchronous satellite, thereby effectively improving the resolution success rate and reliability of the domain name resolution request, reducing the above-mentioned terminal device network access failures, and improving the user experience.

[0324] In addition, based on the communication method in the embodiment of the present application, the application server corresponding to the target domain name closest to the coverage geographical range of the low-orbit satellite 200 can be selected based on the access satellite of the terminal device, such as the network coverage location information of the above-mentioned low-orbit satellite 200, and the IP address of the nearest application server can be sent to the terminal device as the IP address corresponding to the target domain name. In this way, the access path and delay of the terminal device can be effectively shortened.

[0325] In addition, based on the communication method in the embodiment of the present application, by classifying domain name resolution requests, data transmission between geosynchronous satellites and the ground can be reduced, thereby reducing the consumption of satellite resources.

[0326] In some embodiments, the communication method mentioned in the embodiments of the present application can be used in a communication system, which includes a ground system and a satellite system. The ground system includes terminal equipment, a local domain name server, a ground gateway station and other equipment. The satellite system includes a first server, a second server, a UPF, a gNB and other equipment. The first server is deployed on a first satellite, and the first satellite operates in a first earth orbit. The second server is deployed on a second satellite, and the second satellite operates in a second earth orbit, which is higher than the first earth orbit.

[0327] The embodiment of the present application provides a satellite system, including the first server and the second server, UPF, gNB and other devices mentioned in the embodiment of the present application. The satellite system provided in the embodiment of the present application can execute the communication method executed by each device in the satellite system in the embodiment of the present application.

[0328] It should be noted that the methods and features in the embodiments of the present application can be combined in any form, that is, the embodiments formed by combining the methods and features in the embodiments of the present application in any form are within the protection scope of the embodiments of the present application.

[0329] The following is an introduction to the structures of the terminal device 100, the primary server 203, the secondary server 501 and the LDNS 400 mentioned in the embodiment of the present application.

[0330] Fig.11 A schematic diagram of the structure of a terminal device 100 is shown. Fig.11 As shown, the terminal device 100 may include a processor 110, a power module 140, a memory 180, a mobile communication module 130, a wireless communication module 120, a sensor module 190, an audio module 150, a camera 170, an interface module 160, a button 1010 and a display screen 102, etc.

[0331] Fig.12 A schematic diagram of the structure of a server 1200 is shown. Fig.12 The server 1200 shown may be the structure of the primary server 501, the secondary server 203 or the LDNS 400 mentioned in the embodiments of the present application.

[0332] In one embodiment, the server 1200 may include one or more processors 1204, a system control logic 1208 connected to at least one of the processors 1204, a system memory 1212 connected to the system control logic 1208, a non-volatile memory 1216 connected to the system control logic 1208, and a network interface 1220 connected to the system control logic 1208.

[0333] In some embodiments, the processor 1204 may include one or more single-core or multi-core processors. In some embodiments, the processor 1204 may include any combination of a general-purpose processor and a dedicated processor (e.g., a graphics processor, an application processor, a baseband processor, etc.). In an embodiment where the server 1200 uses an enhanced base station (evolved Node B, eNB) or a radio access network (Radio Access Network, RAN) controller, the processor 1204 may be configured to execute various compliant embodiments, for example, it may be used to execute the method required to be executed by the primary server 501, the secondary server 203 or the LDNS400 in the embodiment of the present application.

[0334] An embodiment of the present application provides a computer-readable storage medium storing executable instructions, which, when executed on an electronic device, implement the communication method provided in the embodiment of the present application.

[0335] An embodiment of the present application provides an electronic device, comprising: a memory for storing instructions executed by one or more processors of the electronic device, and one or more processors for executing the communication method provided in the embodiment of the present application.

[0336] The various embodiments of the mechanism disclosed in the present application can be implemented in hardware, software, firmware or a combination of these implementation methods. The embodiments of the present application can be implemented as a computer program or program code executed on a programmable system, which includes at least one processor, a storage system (including volatile and non-volatile memory and / or storage elements), at least one input device and at least one output device.

[0337] Program code can be applied to input instructions to perform each function described in the present application and generate output information. Output information can be applied to one or more output devices in a known manner. For the purpose of the present application, the processing system includes any system with a processor such as, for example, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC) or a microprocessor.

[0338] Program code can be implemented with high-level programming language or object-oriented programming language to communicate with the processing system. When necessary, program code can also be implemented with assembly language or machine language. In fact, the mechanism described in this application is not limited to the scope of any specific programming language. In either case, the language can be a compiled language or an interpreted language.

[0339] In some cases, the disclosed embodiments may be implemented in hardware, firmware, software, or any combination thereof. The disclosed embodiments may also be implemented as instructions carried or stored on one or more temporary or non-temporary machine-readable (e.g., computer-readable) storage media, which may be read and executed by one or more processors. For example, the instructions may be distributed over a network or through other computer-readable media. Therefore, machine-readable media may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer), including, but not limited to, floppy disks, optical disks, optical discs, read-only memories (CD-ROMs), magneto-optical disks, read-only memories (ROMs), random access memories (RAMs), erasable programmable read-only memories (EPROMs), electrically erasable programmable read-only memories (EEPROMs), magnetic or optical cards, flash memory, or a tangible machine-readable memory for transmitting information (e.g., carrier waves, infrared signals, digital signals, etc.) using the Internet in electrical, optical, acoustic, or other forms of propagation signals. Therefore, machine-readable media include any type of machine-readable media suitable for storing or transmitting electronic instructions or information in a form readable by a machine (e.g., a computer).

[0340] In the accompanying drawings, some structural or method features may be shown in a specific arrangement and / or order. However, it should be understood that such a specific arrangement and / or order may not be required. Instead, in some embodiments, these features may be arranged in a manner and / or order different from that shown in the illustrative drawings. In addition, the inclusion of structural or method features in a particular figure does not mean that such features are required in all embodiments, and in some embodiments, these features may not be included or may be combined with other features.

[0341] It should be noted that the units / modules mentioned in the various device embodiments of the present application are all logical units / modules. Physically, a logical unit / module can be a physical unit / module, or a part of a physical unit / module, or can be implemented as a combination of multiple physical units / modules. The physical implementation method of these logical units / modules themselves is not the most important. The combination of functions implemented by these logical units / modules is the key to solving the technical problems proposed by the present application. In addition, in order to highlight the innovative part of the present application, the above-mentioned device embodiments of the present application do not introduce units / modules that are not closely related to solving the technical problems proposed by the present application, which does not mean that there are no other units / modules in the above-mentioned device embodiments.

[0342] It should be noted that in the examples and description of this patent, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one" do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0343] Although the present application has been illustrated and described with reference to certain preferred embodiments thereof, it will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application.

Claims

1. A communication method, characterized in that: Used in a satellite system, the satellite system comprising a first server and a second server, the first server being deployed on a first satellite, the first satellite being operated in a first earth orbit, the second server being deployed on a second satellite, the second satellite being operated in a second earth orbit, the second earth orbit being higher than the first earth orbit; The method comprises: The first server receives a first domain name resolution request sent by a terminal device in the ground system, the first domain name resolution request includes a first domain name requested to be resolved by the terminal device, and the first server stores a mapping relationship between the domain name and the IP address; When the first server determines, based on the mapping relationship between the domain name and the IP address, that the first server does not store the first IP address corresponding to the first domain name, the first server sends the first domain name resolution request to the second server, wherein the first server sends the first domain name resolution request to the second server, including: the first server identifies the first domain name resolution request as a first-category domain name resolution request, and sends the first domain name resolution request to the second server, wherein the classification of the first domain name resolution request is determined based on the contract information corresponding to the application corresponding to the first domain name and / or user plane forwarding rule information; The second server determines, based on the mapping relationship between the domain name and the IP address stored in the second server, that the first IP address corresponding to the first domain name is not stored in the second server, and sends the first domain name resolution request to the local domain name server in the ground system, wherein the period at which the second server updates the mapping relationship between the domain name and the IP address from the local domain name server is less than or equal to the period at which the first server updates the mapping relationship between the domain name and the IP address from the local domain name server; The second server receives the first IP address corresponding to the first domain name sent by the local domain name server; The second server sends the first IP address to the first server; The first server sends the first IP address to the terminal device.

2. The communication method according to claim 1, characterized in that: The satellite system also includes a user plane function UPF; The first server receives a first domain name resolution request sent by a terminal device in the ground system, including: The user plane function UPF receives the first domain name resolution request sent by the terminal device in the ground system; The user plane function UPF determines that the first domain name resolution request is a first type of domain name resolution request based on the first domain name in the first domain name resolution request, marks a first identifier for the first domain name resolution request, and sends the first domain name resolution request and the first identifier to the first server.

3. The communication method according to claim 2, characterized in that: The user plane function UPF determines, based on the first domain name in the first domain name resolution request, that the first domain name resolution request is a first-type domain name resolution request, including: The user plane function UPF determines the application corresponding to the first domain name based on the first domain name in the first domain name resolution request, obtains the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name, and determines that the first domain name resolution request is a first-class domain name resolution request based on the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name; or, The user plane function UPF obtains user plane forwarding rule information corresponding to the first domain name based on the first domain name in the first domain name resolution request, and determines that the first domain name resolution request is the first type of domain name resolution request based on the user plane forwarding rule information corresponding to the first domain name.

4. The communication method according to claim 1, characterized in that: The first server identifies the first domain name resolution request as a first-type domain name resolution request, including: The first server receives the first domain name resolution request and the first identifier sent by the user plane function UPF, and identifies the first domain name resolution request as the first type of domain name resolution request based on the first identifier.

5. The communication method according to any one of claims 1 to 4, characterized in that: The method further comprises: The first server receives a second domain name resolution request sent by the terminal device, where the second domain name resolution request includes a second domain name requested to be resolved by the terminal device; When the first server determines, based on the mapping relationship between the domain name and the IP address, that the first server does not store the second IP address corresponding to the second domain name, and identifies the second domain name resolution request as a second-type domain name resolution request, it sends resolution failure information to the terminal device.

6. The communication method according to claim 5, characterized in that: The first server receives the second domain name resolution request sent by the terminal device, including: A user plane function UPF receives the second domain name resolution request sent by the terminal device; The user plane function UPF determines that the second domain name resolution request is the second type of domain name resolution request based on the second domain name in the second domain name resolution request, marks the second domain name resolution request with a second identifier, and sends the second domain name resolution request and the second identifier to the first server.

7. The communication method according to any one of claims 1 to 4, characterized in that: The satellite system further includes a third server, the third server is deployed on a third satellite, the third satellite and the first satellite are located in the same constellation, and there is an inter-satellite routing path between the third satellite and the second satellite; The first server sending the first domain name resolution request to the second server includes: The first server determines that there is no inter-satellite routing path between the first satellite and the second satellite, the first server sends the first domain name resolution request to the third server, and the third server sends the first domain name resolution request to the second server.

8. The communication method according to any one of claims 1 to 4, characterized in that: The ground system also includes an ephemeris server; The first server sending the first domain name resolution request to the second server includes: the first server sending the first domain name resolution request and identification information of the first satellite to the second server; The second server receives the first IP address corresponding to the first domain name sent by the local domain name server, including: The ephemeris server receives the identification information of the first satellite sent by the local domain name server, and the ephemeris server is used to store the mapping relationship between the satellite identification information and the ephemeris information; The ephemeris server obtains the ephemeris information corresponding to the first satellite based on the identification information of the first satellite; The ephemeris server determines the network coverage ground range information of the first satellite based on the ephemeris information of the first satellite; The ephemeris server sends the network coverage ground range information of the first satellite to the local domain name server; The second server receives the first IP address corresponding to the first domain name sent by the local domain name server, wherein the first IP address is obtained by the local domain name server based on the network coverage ground range information of the first satellite and the mapping relationship between the domain name and the IP address stored in the local domain name server.

9. The communication method according to claim 8, characterized in that: The network coverage ground range information of the first satellite includes: location information of a ground gateway station to which the first satellite is currently connected.

10. The communication method according to claim 9, characterized in that: The manner in which the local domain name server acquires the first IP address based on the network coverage location information of the first satellite and the mapping relationship between the domain name and the IP address stored in the local domain name server includes: The local domain name server determines at least one IP address corresponding to the first domain name based on a mapping relationship between domain names and IP addresses stored in the local domain name server; The local domain name server selects the first IP address from the at least one IP address, and the first IP address is the IP address corresponding to the application server closest to the location information of the ground gateway station.

11. A communication method, characterized in that: Used in a satellite system, the satellite system comprising a user plane function UPF, a first server and a second server, the first server being deployed on a first satellite, the first satellite being operated in a first earth orbit, the second server being deployed on a second satellite, the second satellite being operated in a second earth orbit, the second earth orbit being a geosynchronous orbit, and the second earth orbit being higher than the first earth orbit; The method comprises: The user plane function UPF receives a first domain name resolution request sent by a terminal device in a ground system; the first domain name resolution request includes a first domain name requested to be resolved by the terminal device; The user plane function UPF determines that the first domain name resolution request is a first-category domain name resolution request based on the first domain name in the first domain name resolution request, and sends the first domain name resolution request to the second server, where the classification of the first domain name resolution request is determined based on the subscription information corresponding to the application corresponding to the first domain name and / or the user plane forwarding rule information; The second server determines, based on the mapping relationship between the domain name and the IP address stored in the second server, that the first IP address corresponding to the first domain name is not stored in the second server, and sends the first domain name resolution request to the local domain name server in the ground system, wherein the period at which the second server updates the mapping relationship between the domain name and the IP address from the local domain name server is less than or equal to the period at which the first server updates the mapping relationship between the domain name and the IP address from the local domain name server; The second server receives the first IP address corresponding to the first domain name sent by the local domain name server; The second server sends the first IP address to the terminal device; The user plane function UPF receives a second domain name resolution request sent by the terminal device; The user plane function UPF determines that the second domain name resolution request is a second type of domain name resolution request based on the second domain name in the second domain name resolution request, and sends the second domain name resolution request to the first server.

12. The communication method according to claim 11, characterized in that: The method further comprises: When the first server determines, based on the mapping relationship between the domain name and the IP address, that the first server does not store the second IP address corresponding to the second domain name, the first server sends resolution failure information to the terminal device; When the first server determines, based on the mapping relationship between the domain name and the IP address, that the first server stores the second IP address corresponding to the second domain name, the first server sends the second IP address to the terminal device.

13. A satellite system, characterized in that: include: a first server and a second server, wherein the first server is deployed on a first satellite, the first satellite operates in a first earth orbit, and the second server is deployed on a second satellite, the second satellite operates in a second earth orbit, and the second earth orbit is higher than the first earth orbit; The first server is used to receive a first domain name resolution request sent by a terminal device in the ground system, the first domain name resolution request includes a first domain name requested to be resolved by the terminal device, and the first server stores a mapping relationship between the domain name and the IP address; The first server is configured to send the first domain name resolution request to the second server when it is determined that the first server does not store the first IP address corresponding to the first domain name based on the mapping relationship between the domain name and the IP address; wherein the sending of the first domain name resolution request to the second server includes: identifying the first domain name resolution request as a first-category domain name resolution request, and sending the first domain name resolution request to the second server, wherein the classification of the first domain name resolution request is determined based on the contract information corresponding to the application corresponding to the first domain name and / or the user plane forwarding rule information; The second server is configured to determine that the first IP address corresponding to the first domain name is not stored in the second server based on the mapping relationship between the domain name and the IP address stored in the second server, and send the first domain name resolution request to the local domain name server in the ground system, wherein the period at which the second server updates the mapping relationship between the domain name and the IP address from the local domain name server is less than or equal to the period at which the first server updates the mapping relationship between the domain name and the IP address from the local domain name server; The second server is used to receive the first IP address corresponding to the first domain name sent by the local domain name server; The second server is used to send the first IP address to the first server; The first server is used to send the first IP address to the terminal device.

14. The satellite system according to claim 13, characterized in that: The satellite system also includes a user plane function UPF; The user plane function UPF is used to receive the first domain name resolution request sent by the terminal device; The user plane function UPF is used to determine that the first domain name resolution request is a first type of domain name resolution request based on the first domain name in the first domain name resolution request, mark the first domain name resolution request with a first identifier, and send the first domain name resolution request and the first identifier to the first server.

15. The satellite system according to claim 14, characterized in that: The user plane function UPF is used to determine the application corresponding to the first domain name based on the first domain name in the first domain name resolution request, and obtain the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name, and determine that the first domain name resolution request is a first-class domain name resolution request based on the contract information and / or user plane forwarding rule information corresponding to the application corresponding to the first domain name; or The user plane function UPF is used to determine the user plane forwarding rule information corresponding to the first domain name based on the first domain name in the first domain name resolution request, and determine that the first domain name resolution request is the first type of domain name resolution request based on the user plane forwarding rule information corresponding to the first domain name.

16. A computer-readable storage medium, characterized in that: Executable instructions are stored, and when the instructions are executed on an electronic device, the communication method according to any one of claims 1 to 12 is implemented.

17. An electronic device, characterized in that: include: A memory for storing instructions executed by one or more processors of an electronic device, and the one or more processors for executing the communication method according to any one of claims 1 to 12.

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