Network communication method and device suitable for space-based distributed operating system

Abstract

The invention discloses a network communication method and device suitable for a space-based distributed operating system, and the method comprises the steps: a satellite gateway node obtains a network layer data packet transmitted by an edge computing node, carries out the processing and packaging of the network layer data packet according to a data link layer protocol in a CCSDS protocol system, and transmits the network layer data packet to a ground station through a baseband and a radio frequency device; and after acquiring the data link layer data packet, the node, connected with the baseband equipment, of the ground station processes the data packet step by step according to a corresponding data link layer protocol and removes a data link layer packet header until an internal network layer data packet is acquired, and sends the internal network layer data packet to a corresponding control node. Establishing a communication tunnel between an edge computing node and a control node in the space-based distributed operating system; and the control node transmits the network layer data packet to the edge computing node through the communication tunnel by using the same communication line. According to the invention, the process running at the edge computing node and the control node can carry out network communication without any adaptation.

Description

Technical Field

[0001] The present invention relates to the technical field of space-based systems, and in particular, to a network communication method and device applicable to a space-based distributed operating system. Background Art

[0002] With the continuous development and research in the space field, space computing has become a major trend in future development. A space-based distributed operating system consists of a ground computer cluster as control nodes and intelligent computers on satellites as edge computing nodes, jointly forming a space-ground integrated distributed operating system cluster.

[0003] Among the nodes within the space-based distributed operating system, communication is required between each other. However, different from the ground network, satellite-to-ground communication uses microwaves as the carrier. After the satellite is connected to the radio frequency equipment in the ground station, it can be connected to the ground. Therefore, space-ground connection and communication have their unique characteristics: during the rotation of the satellite around the earth, it can only be connected to the ground during the window period, so the connection between the satellite and the ground is extremely unstable; the uplink and downlink of the satellite-to-ground connection are independent of each other and are asymmetric transmission links; the communication method between the satellite and the ground must conform to the CCSDS protocol system, which is different from the commonly used TCP / IP protocol system for ground communication; when the satellite is connected to the ground, the ground station it connects to and the radio frequency equipment in the ground station will change dynamically, so the communication route from the ground to the satellite needs to be updated in real time.

[0004] On the other hand, the control nodes of the space-based distributed operating system are located in the internal network of the control center, the edge computing nodes of the space-based distributed operating system are located in the internal network of the satellite, and the forwarding equipment in the ground station connected to the satellite is located in the internal network of the ground station. Several devices located in different internal networks need to communicate with each other. In addition to meeting the differences in space-ground communication mentioned above, it is also necessary to break through the communication barriers between different internal networks.

[0005] Therefore, the present invention proposes a network communication method applicable to a space-based distributed operating system, which not only shields the differences between space-ground communication and ground network communication, but also breaks through the communication barriers between different internal networks, and establishes a communication tunnel between the control nodes and edge computing nodes of the space-based distributed operating system, enabling the service software running on the two types of nodes to communicate normally without any adaptation modification. Summary of the Invention

[0006] The purpose of the present invention is to provide a network communication method and device applicable to a space-based distributed operating system in view of the deficiencies of the prior art.

[0007] The purpose of the present invention is achieved through the following technical solutions: In the first aspect of the embodiments of the present invention, a network communication method applicable to a space-based distributed operating system is provided, specifically including: The satellite network gateway node acquires the network layer data packets sent by the edge computing nodes, processes and packages them according to the data link layer protocol in the CCSDS protocol system, and then sends them to the ground station through the baseband and radio frequency devices; after the node connected to the baseband device of the ground station acquires the data link layer data packets, it processes the data packets step by step according to the corresponding data link layer protocol and removes the data link layer packet header until the internal network layer data packets are acquired and sent to the corresponding control nodes, so as to realize the network communication from the edge computing nodes to the control nodes in the space-based distributed operating system; After the control center satellite access network gateway node acquires the network layer data packets sent by the control nodes, it processes and packages them step by step according to the corresponding transmission control protocol and then sends them to the node connected to the baseband device of the next-hop ground station until the data link layer data packets are acquired by the ground station radio frequency device node, the internal network layer data packets are taken out, processed and packaged according to the data link layer protocol in the CCSDS protocol system, and then sent to the satellite network gateway node through the baseband and radio frequency devices; the satellite network gateway node removes the data link layer packet header according to the corresponding data link layer protocol, takes out the internal network layer data packets and sends them to the corresponding edge computing nodes, so as to realize the network communication from the control nodes to the edge computing nodes in the space-based distributed operating system.

[0008] Further, the realization of the network communication from the edge computing nodes to the control nodes in the space-based distributed operating system specifically includes the following steps: S11. Configure routing rules on the edge computing nodes to send the network layer data packets sent by the edge computing nodes to the corresponding satellite network gateway nodes; S12. After the satellite network gateway node receives the network layer data packets, configure routing rules on the current satellite network gateway node, process the network layer data packets according to the data link layer protocol in the CCSDS protocol system, repackage the corresponding data link layer protocol packet header, and then send them to the ground station radio frequency device node through the baseband and radio frequency devices; S13. After the ground station radio frequency device node receives the data link layer data packets, remove the data link layer packet header according to the corresponding data link layer protocol, take out the internal network layer data packets as internal data, process and package them according to the corresponding transmission control protocol, and then send them to the ground station network gateway node; S14. After the ground station network gateway node receives the data packets sent by the previous-hop node, strip the outer transmission control protocol packet header, take out the internal network layer data packets as internal data, process and package them according to the corresponding transmission control protocol, and then send them to the control center satellite access network gateway node; at the same time, record the routing mapping relationship between the inner source IP address and the outer transmission control protocol transmission information at the current node; After the control center satellite access network gateway node receives the data packet sent by the previous hop node, it strips the outer Transmission Control Protocol (TCP) header, extracts the internal network layer data packet, and sends it to the corresponding control node. At the same time, the routing mapping relationship between the inner layer source IP address and the outer layer TCP transmission information is recorded at the current node.

[0009] Further, in step S11, the specific content of the routing rule configured on the edge computing node is: send the network layer data packet with the destination IP address belonging to the internal network segment of the ground control center to the satellite network gateway node of the satellite internal network segment to which the source IP address belongs. In step S12, the specific content of the routing rule configured on the satellite network gateway node is: send the network layer data packet with the destination IP address belonging to the internal network segment of the ground control center to the virtual tun device created by the current satellite network gateway node.

[0010] Further, in step S14, the routing mapping relationship between the inner layer source IP address and the outer layer TCP transmission information recorded by the ground station network gateway node is specifically: the routing mapping relationship between the IP address of the edge computing node and the TCP connection of the ground station radio frequency device node. In step S15, the routing mapping relationship between the inner layer source IP address and the outer layer TCP transmission information recorded by the control center satellite access network gateway node is specifically: the routing mapping relationship between the IP address of the edge computing node and the TCP connection of the ground station network gateway node.

[0011] Further, the realization of the network communication from the control node to the edge computing node in the space-based distributed operating system specifically includes the following steps: S21. Configure a routing rule on the control node to send the network layer data packet sent by the control node to the corresponding control center satellite access network gateway node. S22. After the control center satellite access network gateway node receives the network layer data packet, configure a routing rule on the current control center satellite access network gateway node, process and package it according to the corresponding TCP, and then send it to the corresponding ground station network gateway node according to the routing mapping relationship recorded at the current node. S23. After the ground station network gateway node receives the data packet sent by the previous hop node, strip the outer TCP header, extract the internal network layer data packet as internal data, process and package it according to the corresponding TCP, and then send it to the corresponding ground station radio frequency device node according to the routing mapping relationship recorded at the current node. After the ground station radio frequency device node receives the data packet sent by the previous-hop node, it strips the outer Transmission Control Protocol (TCP) packet header, extracts the internal network layer data packet, processes it according to the data link layer protocol in the CCSDS protocol system, repackages the corresponding data link layer protocol packet header, and then sends it to the satellite gateway node through the baseband and radio frequency devices; After the satellite gateway node receives the data link layer data packet, it removes the data link layer packet header according to the corresponding data link layer protocol, extracts the internal network layer data packet, and sends it to the corresponding edge computing node.

[0012] Further, in the step S21, the specific content of the routing rule configured on the control node is: send the network layer data packet with the destination IP address in the satellite internal network segment to the control center satellite access gateway node in the internal network segment of the control center to which the source IP address belongs; In the step S22, the specific content of the routing rule configured on the control center satellite access gateway node is: send the network layer data packet with the destination IP address in the satellite internal network segment to the virtual tun device created by the current control center satellite access gateway node.

[0013] Further, in the step S22, sending to the corresponding ground station gateway node according to the routing mapping relationship recorded by the current node specifically includes: the control center satellite access gateway node finds the TCP connection of the ground station gateway node corresponding to the IP address of the edge computing node corresponding to the destination IP address in the network layer data packet received from the routing mapping relationship recorded by the current control center satellite access gateway node, and sends the processed and packaged data packet to the corresponding ground station gateway node through the TCP connection of the corresponding ground station gateway node; In the step S23, sending to the corresponding ground station radio frequency device node according to the routing mapping relationship recorded by the current node specifically includes: the ground station gateway node finds the TCP connection of the ground station radio frequency device node corresponding to the IP address of the edge computing node corresponding to the destination IP address in the internal network layer data packet extracted from the routing mapping relationship recorded by the current ground station gateway node, and sends the processed and packaged data packet to the corresponding ground station radio frequency device node through the TCP connection of the corresponding ground station radio frequency device node.

[0014] Further, the data link layer protocol includes the AOS protocol, TM protocol, TC protocol, and Prox-1 protocol; The Transmission Control Protocol includes the TCP protocol.

[0015] In a second aspect of the embodiments of the present invention, a network communication device applicable to a space-based distributed operating system is provided, which includes one or more processors and a memory, and the memory is coupled to the processors; wherein, the memory is used to store program data, and the processors are used to execute the program data to implement the above-mentioned network communication method applicable to the space-based distributed operating system.

[0016] In a third aspect of the embodiments of the present invention, a computer-readable storage medium is provided, on which a program is stored. When the program is executed by a processor, it is used to implement the above-mentioned network communication method applicable to the space-based distributed operating system.

[0017] The beneficial effects of the present invention are as follows: The present invention can establish a communication tunnel for network layer data packets between the control node of the space-based distributed operating system located on the ground and the edge computing node of the space-based distributed operating system located on the satellite. This communication tunnel can achieve transparent transmission of IP protocol data packets, shield the differences between the ground network and the space-ground network for the communication between nodes in the space-based distributed operating system, enable normal communication between nodes in the space-based distributed operating system, and enable the processes on both ends of the nodes to perform network communication without any adaptation; the present invention not only shields the differences between space-ground communication and ground network communication, but also breaks the communication barriers between different internal networks, enabling the business software running on the two types of nodes to communicate normally without any adaptation modification. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of network communication between the control node and the edge computing node in the space-based distributed operating system of the present invention; Figure 2 It is a communication tunnel diagram between the control node and the edge computing node in the space-based distributed operating system of the present invention; Figure 3 It is a schematic diagram of the detailed processing process of each node in the communication tunnel of the present invention; Figure 4 It is a schematic diagram of data packet transfer between each node in the communication tunnel of the present invention; Figure 5 It is a schematic structural diagram of a network communication device applicable to the space-based distributed operating system of the present invention. Detailed Embodiments

[0019] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. Obviously, the accompanying drawings used in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0020] The terms used in the present invention are for the purpose of describing particular embodiments only and are not intended to limit the present invention. The singular forms "a", "the", and "said" used in the present invention and the appended claims are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0021] It should be understood that although the terms first, second, third, etc. may be used in the present invention to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to determining".

[0022] The present invention will be described in detail below with reference to the accompanying drawings. Without conflict, the features in the following embodiments and implementation manners may be combined with each other.

[0023] The network communication method applicable to the space-based distributed operating system of the present invention specifically includes: The satellite gateway node acquires the network layer data packets sent by the edge computing node, processes and packages them according to the data link layer protocol in the CCSDS protocol system, and then sends them to the ground station through the baseband and radio frequency devices; After the node connected to the baseband device of the ground station acquires the data link layer data packet, it processes the data packet step by step according to the corresponding data link layer protocol and removes the data link layer header until the internal network layer data packet is obtained. This internal network layer data packet is the network layer data packet sent by the edge computing node and is sent to the corresponding control node to realize the network communication from the edge computing node to the control node in the space-based distributed operating system and complete the establishment of the communication tunnel between the edge computing node and the control node. Using the same communication line, the control node of the space-based distributed operating system transmits the network layer data packet to the edge computing node through this communication tunnel, that is: After the control center satellite access gateway node acquires the network layer data packet sent by the control node, it processes and packages it step by step according to the corresponding transmission control protocol and then sends it to the node connected to the baseband device of the next-hop ground station until the data link layer data packet is obtained by the ground station radio frequency device node. The internal network layer data packet is taken out, processed and packaged according to the data link layer protocol in the CCSDS protocol system, and then sent to the satellite gateway node through the baseband and radio frequency devices; The satellite gateway node removes the data link layer header according to the corresponding data link layer protocol to take out the internal network layer data packet. This internal network layer data packet is the network layer data packet sent by the control node and is sent to the corresponding edge computing node to realize the network communication from the control node to the edge computing node in the space-based distributed operating system.

[0024] It should be understood that the present invention can establish a communication tunnel for network layer data packets between the control node of the space-based distributed operating system located on the ground and the edge computing node of the space-based distributed operating system located on the satellite, shielding the differences between the ground network and the space-ground network for the communication between the nodes in the space-based distributed operating system, enabling the normal communication between the nodes in the space-based distributed operating system.

[0025] Take Figure 1 the space-based distributed operating system in Figure 1As shown in the figure, it is a schematic diagram of network communication between control nodes and edge computing nodes in the space-based distributed operating system. The entire network communication process involves four network environments: satellite intranet, ground station intranet, ground public network, and control center intranet. Specifically, it involves six physical device nodes: edge computing node, satellite gateway node, ground station RF device node, ground station gateway node, control center satellite access gateway node, and control node. At the same time, assuming that there are ground station 1 and ground station 2, at the current moment, RF device 1 of ground station 1 is connected to satellite 1, RF device 2 of ground station 1 is connected to satellite 2, and RF devices in ground station 2 are connected to satellite 3 and satellite 4 respectively. The intelligent computers on the four satellites are all connected to the ground control center as edge computing nodes in the space-based distributed operating system. At the same time, for the convenience of subsequent description, it is assumed that the network layer protocol adopts the IP protocol (Internet Protocol), the data link layer protocol in the CCSDS (Consultative Committee for Space Data Systems) protocol system adopts the AOS protocol (Advanced Onboard Systems Protocol), and the establishment of tunnels between different intranets on the ground adopts the TCP protocol (Transmission Control Protocol) as the outer layer protocol of the tunnel. According to the method described in the present invention, the communication tunnel between the edge computing node and the control node in the space-based distributed operating system is opened, and the network communication between the nodes in the space-based distributed operating system can be realized.

[0026] It should be noted that, in addition to the IP protocol, the network layer protocol can also be replaced by the ICMP protocol (Internet Control Message Protocol), the ARP protocol (Address Resolution Protocol), etc., which can be selected according to actual needs; of course, the network layer protocol preferably uses the IP protocol. In addition to the AOS protocol, the data link layer protocol in the CCSDS protocol system can also be replaced by the TM protocol (Telemetry Protocol), the TC protocol (Telecommand Protocol), the Prox-1 protocol (Proximity-1 Protocol), etc., which can be selected according to actual needs; of course, the data link layer protocol in the CCSDS protocol system preferably uses the AOS protocol.

[0027] In this embodiment, network communication from the edge computing node on the satellite to the ground control node in the space-based distributed operating system is realized, which specifically includes the following steps: Step S11: Configure routing rules on the edge computing nodes in the satellite internal network to send the network layer data packets sent by the edge computing nodes to the corresponding satellite gateway nodes.

[0028] Specifically, as Figure 2 shown, when a satellite needs to send a network layer data packet to the ground, a specific single network layer data packet needs to be sent from the edge computing node to the control node. The network layer data packet contains a source IP address and a destination IP address, where the source IP address belongs to the satellite internal network segment and the destination IP address belongs to the ground control center internal network segment. This network layer data packet first needs to be sent out from the edge computing node and sent to the next-hop node. If it is necessary to determine which specific node the next-hop node is, then routing rules need to be configured on the edge computing nodes in the satellite internal network. The specific content of the routing rules configured on this edge computing node includes: sending the network layer data packet with the destination IP address being the ground control center internal network segment to the satellite gateway node in the satellite internal network segment to which the source IP address belongs. Due to the existence of this routing rule, the edge computing node can know that the sent network layer data packet needs to be sent to the corresponding satellite gateway node. Therefore, the network layer data packet sent from the edge computing node on the satellite to the ground control node will first be sent from the edge computing node to the corresponding satellite gateway node, and then the satellite gateway node is responsible for delivering this network layer data packet to the control node where the destination IP address is located.

[0029] It should be noted that whether routing rules need to be configured on each node in the space-based distributed operating system specifically depends on whether the destination IP address of the message sent by the current physical device node and the current physical device node are in the same second-layer network segment. If so, no routing rules need to be configured; otherwise, routing rules need to be configured. For example, in step S11, in the network layer data packet sent by the edge computing node, the destination IP address is the IP address of the control node, which belongs to the ground control center internal network segment, while the IP address of the current edge computing node belongs to the satellite internal network segment, and the two are not in the same second-layer network segment. Therefore, routing rules need to be configured on the edge computing node to send the network layer data packet sent by the edge computing node to the corresponding satellite gateway node.

[0030] Step S12: At the satellite gateway node, capture the network layer data packet sent from the edge computing node to the control node, configure routing rules on the satellite gateway node, then process the network layer data packet according to the data link layer protocol in the CCSDS protocol system and repackage the corresponding data link layer protocol header, and then send it to the ground station through the baseband and radio frequency devices.

[0031] Specifically, after the satellite gateway node receives the network layer data packet sent by the edge computing node, its internal processing process is as Figure 3As shown in the satellite network gateway node, this satellite network gateway node uses the Linux operating system. This satellite network gateway node includes a physical network card and a radio frequency device, and creates a virtual tun device on this satellite network gateway node, enables the network layer packet forwarding function and configures routing rules. Among them, the specific content of the routing rules configured on the satellite network gateway node includes: sending network layer packets with the destination IP address being the internal network segment of the ground control center to the virtual tun device of the current satellite network gateway node. After the above routing rules are configured, the network layer packets received by the physical network card in the satellite network gateway node will enter the operating system protocol stack of the current satellite network gateway node, that is, the Linux operating system protocol stack, and send the network layer packets to the virtual tun device according to the routing rules configured on the current satellite network gateway node. The forwarding program reads the network layer packets from the virtual tun device; since the data link layer protocol in the CCSDS protocol system uses the AOS protocol, the forwarding program reassembles the captured network layer packets according to the AOS protocol in the CCSDS protocol system and adds the AOS protocol header to obtain an AOS protocol packet, and then passes it to the radio frequency device of the current satellite network gateway node, and the radio frequency device passes the AOS protocol packet to the radio frequency device of the ground station.

[0032] Step S13: After the radio frequency device node of the ground station receives the data link layer packet sent by the satellite network gateway node, it removes the data link layer header according to the corresponding data link layer protocol, extracts the intermediate network layer data and reassembles it, and then processes and packages it according to the corresponding transmission control protocol and sends it to the network gateway node of the ground station.

[0033] Specifically, after the radio frequency device node of the ground station receives the data link layer packet sent by the satellite network gateway node, that is, the AOS protocol packet, its internal processing process is as Figure 3As shown in the ground station radio frequency device node, the ground station radio frequency device node includes a physical network card and a radio frequency device, and the network layer packet forwarding function is enabled. When the forwarding program starts, it actively connects to the TCP server located at the ground station network gateway node as a TCP client. After the radio frequency device of the ground station radio frequency device node receives the AOS protocol packet sent by the satellite network gateway node, the radio frequency device passes the AOS protocol packet to the forwarding program. The forwarding program extracts the network layer data in the data link layer packet according to the AOS protocol, reassembles it into an IP protocol packet, and adds a TCP protocol header to the IP protocol packet according to the TCP protocol to wrap the IP protocol packet in the TCP protocol packet. Then, the IP protocol packet can be sent to the ground station network gateway node as the internal data of the TCP protocol packet through the established TCP connection, that is, the obtained TCP protocol packet is passed to the physical network card of the current ground station radio frequency device node, and the physical network card passes the TCP protocol packet to the ground station network gateway node. At this time, the transmitted TCP protocol packet has two network layer headers. The source IP address and destination IP address in the outer network layer header are the IP address of the ground station radio frequency device node and the IP address of the ground station network gateway node respectively, and the source IP address and destination IP address in the inner network layer header are the IP address of the edge computing node and the IP address of the control node respectively.

[0034] Step S14: After the ground station network gateway node receives the packet sent by the ground station radio frequency device node, strip the outer transmission control protocol header and extract the internal network layer data; record the routing mapping relationship between the inner source IP address and the outer TCP protocol transmission information at the current node, that is, the routing mapping relationship between the IP address of the edge computing node and the TCP connection of the ground station radio frequency device node; and take the extracted inner network layer packet as the internal data, process and package it according to the corresponding transmission control protocol, and then send it to the control center satellite access network gateway node.

[0035] Specifically, after the physical network card of the ground station network gateway node receives the TCP protocol packet sent by the ground station radio frequency device node, its internal processing process is as Figure 3As shown by the ground station network node in it, when the forwarding program starts, as a TCP client, it actively connects to the TCP server of the satellite access network node in the control center. After the forwarding program, as a TCP server, receives the TCP protocol data packet sent from the TCP client, it strips the outer TCP protocol header and extracts the internal network layer data. This data is the network layer data packet sent from the edge computing node to the control node. The content of this network layer data packet is the network layer IP protocol data packet. The source IP address is extracted from it, which is the IP address of the edge computing node, and a routing mapping relationship is established between the IP address of the edge computing node and the TCP client connection. Since each network layer data packet sent from the edge computing node to the control node will record the routing mapping relationship when passing through here, multiple routing mapping relationships will form the following routing table, as Figure 1 The satellite access situation of the 4 satellites in it. Assuming that each satellite has 2 edge computing nodes, the routing table recorded on the gateway node of ground station 1 is as follows: IP address of edge computing node 1 of satellite 1 - TCP connection of ground station radio frequency device 1; IP address of edge computing node 2 of satellite 1 - TCP connection of ground station radio frequency device 1; IP address of edge computing node 1 of satellite 2 - TCP connection of ground station radio frequency device 2; IP address of edge computing node 2 of satellite 2 - TCP connection of ground station radio frequency device 2.

[0036] Among them, the above routing table recorded on the gateway node of ground station 1 will change according to the different ground station radio frequency device nodes accessed by the satellite. After the forwarding program of the current ground station network node records the routing, it will use the established TCP connection with the satellite access network node in the control center to wrap the network layer IP protocol data packet as internal data in the TCP protocol data packet and send it to the satellite access network node in the control center. At this time, the transmitted data packet has two network layer headers. The source IP address and destination IP address in the outer network layer header are the IP address of the ground station network node and the IP address of the satellite access network node in the control center respectively. The source IP address and destination IP address in the inner network layer header are the IP address of the edge computing node and the IP address of the control node respectively.

[0037] It should be noted that when the ground control center sends data to the satellite, it needs to know which baseband device of which ground station the satellite accesses. Only by knowing the baseband device of the ground station to which the satellite is connected can the ground control center reach the satellite through this path. Specifically, it can be queried according to the routing table recorded on the ground station network node. In addition, since the satellite may access from different baseband devices of different ground stations each time, the routing table will also change accordingly.

[0038] It should be understood that the forwarding program in the ground station network node can actively connect to the TCP server of the satellite access network node in the control center as a TCP client. The forwarding program in the ground station network node can also act as a TCP server to receive data packets sent by the TCP client from the ground station radio frequency device node.

[0039] Step S15: After the satellite access network node in the control center receives the data packet sent by the ground station network node, strip the outer Transmission Control Protocol (TCP) header and extract the internal network layer data. Record the routing mapping relationship between the inner source IP address and the outer TCP protocol transmission information at the current node, that is, the routing mapping relationship between the IP address of the edge computing node and the TCP connection of the ground station network node. Then send the extracted inner network layer data packet to the network protocol stack of the current satellite access network node in the control center. Since the destination IP address of the network layer data packet is the IP address of the control node, which is in the same network segment as the control center internal network, this network layer data packet will be sent to the corresponding control node, and the process on the control node will capture and process it.

[0040] Specifically, after the physical network card of the satellite access network node in the control center receives the TCP protocol data packet sent by the ground station network node, its internal processing process is as Figure 3 shown in the satellite access network node in the control center. This satellite access network node in the control center uses the Linux operating system. Create a virtual tun device on this satellite access network node in the control center and enable the IP packet forwarding function. After the forwarding program, acting as the TCP server of the satellite access network node in the control center, receives the TCP protocol data packet sent from the TCP client, strip the outer TCP protocol header and extract the internal network layer data. This data is the network layer data packet sent from the edge computing node to the control node. The content of this network layer data packet is the network layer IP protocol data packet. Extract the source IP address from it, which is the IP address of the edge computing node, and establish the routing mapping relationship between the IP address of the edge computing node and the TCP client connection. Since each network layer data packet sent from the edge computing node to the control node will record the routing mapping relationship when passing through here, multiple routing mapping relationships will form the following routing table, as Figure 1 shown in the satellite access situation of 4 satellites. Assuming that each satellite has 2 edge computing nodes, the routing table recorded on the satellite access network node in the control center is as follows: IP address of edge computing node 1 of satellite 1 - TCP connection of ground station 1 gateway; IP address of edge computing node 2 of satellite 1 - TCP connection of ground station 1 gateway; IP address of edge computing node 1 of satellite 2 - TCP connection of ground station 1 gateway; IP address of the edge computing node 2 of satellite 2 - TCP connection to the gateway of ground station 1 IP address of the edge computing node 1 of satellite 3 - TCP connection to the gateway of ground station 2 IP address of the edge computing node 2 of satellite 3 - TCP connection to the gateway of ground station 2 IP address of the edge computing node 1 of satellite 4 - TCP connection to the gateway of ground station 2 IP address of the edge computing node 2 of satellite 4 - TCP connection to the gateway of ground station 2

[0041] Among them, the above - mentioned routing table recorded on the satellite access gateway node of the ground control center will change according to different ground stations accessed by the satellite. After the forwarding program of the satellite access gateway node of the ground control center records the routing table, it will write the network - layer IP protocol data packet into the virtual tun device. Since the destination IP address of the network - layer data packet is the IP address of the control node, which is in the same network segment as the internal network of the control center, this network - layer data packet will be sent to the corresponding control node, and the process on the control node will capture and process it.

[0042] In this embodiment, to implement the network communication from the ground control node to the edge computing node on the satellite in the space - based distributed operating system, the following steps are specifically included: Step S21: Configure routing rules on the control node in the internal network of the control center to send the network - layer data packets sent by the control node to the corresponding satellite access gateway node of the control center.

[0043] Specifically, when the ground needs to send a network - layer data packet to the satellite, a specific single network - layer data packet needs to be sent from the control node to the edge computing node. This network - layer data packet contains a source IP address and a destination IP address, where the source IP address belongs to the internal network segment of the ground control center, and the destination IP address belongs to the internal network segment of the satellite. This network - layer data packet first needs to be sent out from the control node and sent to the next - hop node. If it is necessary to determine which specific node the next - hop node is, routing rules need to be configured on the control node in the internal network of the ground control center. The specific content of the routing rules configured on this control node includes: sending the network - layer data packet with the destination IP address belonging to the internal network segment of the satellite to the satellite access gateway node of the control center in the internal network segment to which the source IP address belongs. Due to the existence of this routing rule, the network - layer data packet sent from the ground control node to the edge computing node on the satellite will first be sent from the control node to the corresponding satellite access gateway node of the control center, and then the satellite access gateway node of the control center is responsible for delivering this network - layer data packet to the edge computing node where the destination IP address is located.

[0044] Step S22: After the control center satellite access network gateway node receives the network layer data packet sent by the control node, it configures routing rules on the current control center satellite access network gateway node, captures the network layer data of this network layer data packet, and finds the corresponding TCP connection of the ground station network gateway node from the routing mapping relationship recorded by the current node according to the destination IP address therein. The extracted network layer data packet is used as internal data and wrapped in a TCP protocol data packet, and is sent to the corresponding ground station network gateway node through the corresponding TCP connection. Herein, the corresponding ground station network gateway node refers to the network gateway node of the ground station to which the satellite is currently connected.

[0045] Specifically, after the control center satellite access network gateway node receives the network layer data packet sent by the control node, its internal processing process is as Figure 3 shown in the control center satellite access network gateway node in. The control center satellite access network gateway node uses the Linux operating system, creates a virtual tun device on the control center satellite access network gateway node, enables the IP packet forwarding function and configures routing rules. Herein, the specific content of the routing rules configured on the control center satellite access network gateway node includes: sending the network layer data packet with the destination IP address being the satellite internal network segment to the virtual tun device of the current control center satellite access network gateway node. As Figure 3 shown, the network layer data packet received from the physical network card will enter the operating system protocol stack of the current control center satellite access network gateway node, that is, the Linux operating system. Since the destination IP address of this network layer data packet is the IP address of the edge computing node in the satellite internal network segment, the network layer data packet is sent to the virtual tun device of the current control center satellite access network gateway node according to the routing rules configured on the control center satellite access network gateway node. The forwarding program reads the data packet from the virtual tun device, and the read data packet is a network layer data packet. Query the routing mapping relationship recorded by the current control center satellite access network gateway node according to the destination IP address in the network layer data packet, find the corresponding TCP connection with the ground station network gateway node, and then use this TCP connection to wrap the network layer data packet as internal data in a TCP protocol data packet and send it to the ground station network gateway node.

[0046] Step S23: After the ground station network gateway node receives the TCP data packet sent by the control center satellite access network gateway node, it strips the TCP protocol header, extracts the internal network layer data packet, finds the corresponding TCP connection of the ground station radio frequency device node from the routing mapping relationship recorded by the current ground station network gateway node according to the destination IP address in this network layer data packet, uses the extracted network layer data packet as internal data, wraps it in a TCP protocol data packet, and sends it to the corresponding ground station radio frequency device node through the corresponding TCP connection. Herein, the corresponding ground station radio frequency device node refers to the ground station radio frequency device node to which the satellite is currently connected.

[0047] Specifically, the forwarding program on the ground station network gateway node acts as a TCP client. After receiving the data packet sent by the TCP server in the ground station radio frequency device node, it strips the TCP protocol header, extracts the internal data, and the extracted internal data is a network layer data packet. According to the destination IP address in this network layer data packet, it queries the routing table recorded by the current ground station network gateway node, that is, the routing mapping relationship, finds the corresponding TCP connection with the ground station radio frequency device node, and then uses this TCP connection to wrap the network layer data packet as internal data in a TCP protocol data packet and send it to the ground station radio frequency device node.

[0048] Step S24: After the ground station radio frequency device node receives the TCP protocol data packet sent by the ground station network gateway node, it strips the TCP protocol header, and the extracted internal data is a network layer data packet. Then, it processes the network layer data packet according to the data link layer protocol in the CCSDS protocol system and repackages the corresponding data link layer protocol header, and then sends it to the satellite network gateway through the baseband and radio frequency devices.

[0049] Specifically, the forwarding program on the ground station radio frequency device node acts as a TCP client. After receiving the TCP protocol data packet sent by the TCP server on the ground station network gateway node, it strips the TCP protocol header, extracts the internal data, and the extracted internal data is a network layer data packet. Then, the forwarding program in the ground station radio frequency device node reassembles the captured network layer data packet according to the AOS protocol in the CCSDS protocol system and adds the AOS protocol header to obtain an AOS protocol data packet, which is passed to the radio frequency device, and the radio frequency device passes the AOS protocol data packet to the satellite network gateway.

[0050] Step S25: After the satellite network gateway captures the data link layer data packet sent by the ground station radio frequency device node, it removes the data link layer header according to the corresponding data link layer protocol and extracts the internal network layer data packet; and sends the extracted inner network layer data packet to the network protocol stack of the current node. Since the destination IP address of the network layer data packet is the IP address of the edge computing node and is in the same network segment as the satellite internal network, this network layer data packet will be sent to the corresponding edge computing node, and the process on the edge computing node captures and processes it.

[0051] Specifically, after the radio frequency device of the satellite gateway node receives the AOS protocol data packet sent by the radio frequency device node of the ground station, it is passed to the forwarding program of the current node for processing. The forwarding program removes the AOS protocol header according to the AOS protocol, extracts the internal network layer data packet, reassembles it into an IP protocol data packet, and writes the IP protocol data packet into the virtual tun device. Since the destination IP address of the network layer data packet is the IP address of the edge computing node, which is in the same network segment as the satellite internal network, the network layer data packet will be sent to the corresponding edge computing node, and will be captured and processed by the process on the edge computing node.

[0052] It should be noted that according to the above method steps, a communication tunnel for network layer data packets can be established between the edge computing node on the satellite and the control node on the ground, and the processes on both ends of the node can communicate without any adaptation. To more clearly describe the data packet transmission between each node in the communication tunnel, as Figure 2 shown, it is the transmission situation of the network layer data packet transmitted between the edge computing node and the control node in the tunnel. Based on the established communication tunnel, the same communication line can be used, and the control node of the space-based distributed operating system transmits the network layer data packet to the edge computing node, realizing the network communication from the ground control node to the edge computing node on the satellite in the space-based distributed operating system.

[0053] As Figure 4 shown, it is a schematic diagram of data packet transmission between each node in the communication tunnel. It can be seen that the present invention establishes a communication tunnel for network layer data packets, that is, IP protocol data packets, between the edge computing node and the control node in the space-based distributed operating system. This communication tunnel can realize the transparent transmission of network layer data packets, that is, IP protocol data packets, and shield the differences between the ground network and the space-ground network for the communication between each node in the space-based distributed operating system, enabling normal communication between each node in the space-based distributed operating system. For example, when the edge computing node transfers the network layer data packet, that is, the IP protocol data packet, to the satellite gateway node, as Figure 4 shown, the data packet transmitted between the edge computing node and the satellite gateway node contains the IP protocol data packet to be transmitted, the Ethernet protocol, and the physical layer. The Ethernet protocol is the outer carrier for the transmission of the IP protocol data packet. Since the edge computing node and the satellite gateway node contain physical network cards, the data packet can be transmitted through the existence of the physical layer. Another example is that the data packet transmitted between the satellite gateway node and the radio frequency device node of the ground station contains the IP protocol data packet to be transmitted and its wrapped AOS protocol header as well as the radio frequency. Through the existence of the radio frequency, the data packet can be sent from the satellite gateway node to the radio frequency device node of the ground station through the baseband and radio frequency devices.

[0054] As can be seen from the above steps, the network communication method of the present invention is essentially a network layer data packet that realizes transmission between an edge computing node and a control node by continuously changing its outer shell. As Figure 2 shown, where IP represents the network layer data packet, and the protocol after "over" represents the continuously changing outer layer protocol or the outer layer carrier for transmission. Ethernet represents the Ethernet protocol, which is a data link layer protocol at the second layer; the AOS protocol is a data link layer protocol at the second layer in the CCSDS protocol system; the TCP protocol is a protocol at the fourth layer of the transport layer. For example, as Figure 2 shown, when the edge computing node transmits a network layer data packet to the control node, since in this embodiment, the network layer protocol uses the IP protocol, the network layer data packet is an IP protocol data packet; using the Ethernet protocol as the outer layer carrier for transmitting the IP protocol data packet, by configuring routing rules on the edge computing node, the IP protocol data packet with the outer layer carrier can be transmitted to the satellite gateway node; after receiving the IP protocol data packet, the satellite gateway node uses the AOS protocol as the outer layer protocol of the IP protocol data packet, that is, adds an AOS protocol header to the IP protocol data packet according to the AOS protocol and sends it to the ground station radio frequency device node through the baseband and radio frequency devices.

[0055] Corresponding to the foregoing embodiments of the network communication method applicable to the space-based distributed operating system, the present invention also provides an embodiment of a network communication device applicable to the space-based distributed operating system.

[0056] See Figure 5 , an embodiment of a network communication device applicable to the space-based distributed operating system provided by the embodiment of the present invention includes one or more processors and a memory, and the memory is coupled to the processor; wherein, the memory is used to store program data, and the processor is used to execute the program data to implement the network communication method applicable to the space-based distributed operating system in the above embodiments.

[0057] The embodiment of the network communication device applicable to the space-based distributed operating system of the present invention can be applied to any device with data processing capabilities, and the any device with data processing capabilities can be a device or apparatus such as a computer. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. Taking software implementation as an example, as a logically meaningful device, it is formed by the processor of any device with data processing capabilities where it is located reading the corresponding computer program instructions in the non-volatile memory into the memory for operation. From the hardware level, as Figure 5 shown, it is a hardware structure diagram of any device with data processing capabilities where the network communication device applicable to the space-based distributed operating system of the present invention is located. Except for Figure 5In addition to the processor, memory, network interface, and non-volatile memory shown, any device with data processing capabilities where the device in the embodiment is located may generally include other hardware according to the actual functions of the device with data processing capabilities, which will not be elaborated here.

[0058] For the specific implementation process of the functions and roles of each unit in the above device, please refer to the implementation process of the corresponding steps in the above method, which will not be elaborated here.

[0059] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can be referred to the partial description of the method embodiment. The device embodiments described above are only illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of the present invention. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0060] The embodiment of the present invention also provides a computer-readable storage medium, on which a program is stored. When the program is executed by a processor, it implements the network communication method applicable to the space-based distributed operating system in the above embodiment.

[0061] The computer-readable storage medium may be an internal storage unit of any device with data processing capabilities described in any of the foregoing embodiments, such as a hard disk or memory. The computer-readable storage medium may also be any device with data processing capabilities, such as a plug-in hard disk, a smart media card (SMC), an SD card, a flash card, etc. equipped on the device. Further, the computer-readable storage medium may also include both an internal storage unit of any device with data processing capabilities and an external storage device. The computer-readable storage medium is used to store the computer program and other programs and data required by the device with data processing capabilities, and can also be used to temporarily store the data that has been output or will be output.

[0062] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A network communication method applicable to a space-based distributed operating system, characterized in that, Specifically, it includes: The satellite network gateway node acquires the network layer data packets sent by the edge computing nodes, processes and packages them according to the data link layer protocol in the CCSDS protocol system, and then sends them to the ground station through the baseband and radio frequency devices; After the node connected to the baseband device of the ground station acquires the data link layer data packets, it processes the data packets step by step according to the corresponding data link layer protocol and removes the data link layer packet header until the internal network layer data packets are acquired, and then sends them to the corresponding control node to realize the network communication from the edge computing node to the control node in the space-based distributed operating system; After the control center satellite access network gateway node acquires the network layer data packets sent by the control node, it processes and packages them step by step according to the corresponding transmission control protocol and then sends them to the node connected to the baseband device of the next-hop ground station until the data link layer data packets are acquired by the ground station radio frequency device node. The internal network layer data packets are taken out, processed and packaged according to the data link layer protocol in the CCSDS protocol system, and then sent to the satellite network gateway node through the baseband and radio frequency devices; The satellite network gateway node removes the data link layer packet header according to the corresponding data link layer protocol, takes out the internal network layer data packets and sends them to the corresponding edge computing nodes to realize the network communication from the control node to the edge computing node in the space-based distributed operating system.

2. The network communication method applicable to the space-based distributed operating system according to claim 1, wherein The realization of the network communication from the edge computing node to the control node in the space-based distributed operating system specifically includes the following steps: S11. Configure routing rules on the edge computing nodes to send the network layer data packets sent by the edge computing nodes to the corresponding satellite network gateway nodes; S12. After the satellite network gateway node receives the network layer data packets, configure routing rules on the current satellite network gateway node, process the network layer data packets according to the data link layer protocol in the CCSDS protocol system, repackage the corresponding data link layer protocol packet header, and then send them to the ground station radio frequency device node through the baseband and radio frequency devices; S13. After the ground station radio frequency device node receives the data link layer data packets, remove the data link layer packet header according to the corresponding data link layer protocol, take out the internal network layer data packets as internal data, and process and package them according to the corresponding transmission control protocol and then send them to the ground station network gateway node; S14. After the ground station network gateway node receives the data packets sent by the previous-hop node, strip the outer transmission control protocol packet header, take out the internal network layer data packets as internal data, and process and package them according to the corresponding transmission control protocol and then send them to the control center satellite access network gateway node; at the same time, record the routing mapping relationship between the inner source IP address and the outer transmission control protocol transmission information at the current node; S15. After the control center satellite access network gateway node receives the data packets sent by the previous-hop node, strip the outer transmission control protocol packet header, take out the internal network layer data packets and send them to the corresponding control node; at the same time, record the routing mapping relationship between the inner source IP address and the outer transmission control protocol transmission information at the current node.

3. The network communication method applicable to the space-based distributed operating system according to claim 2, characterized in that In the step S11, the specific content of the routing rule configured on the edge computing node is as follows: send the network layer data packet with the destination IP address being the internal network segment of the ground control center to the satellite network gateway node of the satellite internal network segment to which the source IP address belongs; In the step S12, the specific content of the routing rule configured on the satellite network gateway node is as follows: send the network layer data packet with the destination IP address being the internal network segment of the ground control center to the virtual tun device created by the current satellite network gateway node.

4. The network communication method applicable to the space-based distributed operating system according to claim 2, wherein In the step S14, the routing mapping relationship between the inner layer source IP address and the outer layer transmission control protocol transmission information recorded by the ground station network gateway node is specifically: the routing mapping relationship between the IP address of the edge computing node and the TCP connection of the ground station radio frequency device node; In the step S15, the routing mapping relationship between the inner layer source IP address and the outer layer transmission control protocol transmission information recorded by the control center satellite access network gateway node is specifically: the routing mapping relationship between the IP address of the edge computing node and the TCP connection of the ground station network gateway node.

5. The network communication method applicable to the space-based distributed operating system according to claim 1, characterized in that, The realization of the network communication from the control node to the edge computing node in the space-based distributed operating system specifically includes the following steps: S21. Configure a routing rule on the control node to send the network layer data packet sent by the control node to the corresponding control center satellite access network gateway node; S22. After receiving the network layer data packet, the control center satellite access network gateway node configures a routing rule on the current control center satellite access network gateway node, and after processing and packaging according to the corresponding transmission control protocol, sends it to the corresponding ground station network gateway node according to the routing mapping relationship recorded by the current node; S23. After receiving the data packet sent by the previous hop node, the ground station network gateway node strips the outer layer transmission control protocol header, takes out the internal network layer data packet as internal data, and after processing and packaging according to the corresponding transmission control protocol, sends it to the corresponding ground station radio frequency device node according to the routing mapping relationship recorded by the current node; S24. After receiving the data packet sent by the previous hop node, the ground station radio frequency device node strips the outer layer transmission control protocol header, takes out the internal network layer data packet, and processes and repackages the corresponding data link layer protocol header according to the data link layer protocol in the CCSDS protocol system, and then sends it to the satellite network gateway node through the baseband and radio frequency devices; S25. After receiving the data link layer data packet, the satellite network gateway node removes the data link layer header according to the corresponding data link layer protocol, and takes out the internal network layer data packet and sends it to the corresponding edge computing node.

6. The network communication method applicable to the space-based distributed operating system according to claim 5, characterized in that, In the step S21, the specific content of the routing rule configured on the control node is as follows: send the network layer data packet with the destination IP address being the satellite internal network segment to the control center satellite access network gateway node of the control center internal network segment to which the source IP address belongs; In the step S22, the specific content of the routing rule configured on the control center satellite access network gateway node is as follows: send the network layer data packet with the destination IP address being the satellite internal network segment to the virtual tun device created by the current control center satellite access network gateway node.

7. The network communication method applicable to the space-based distributed operating system according to claim 5, characterized in that, In the step S22, sending to the corresponding ground station network gateway node according to the routing mapping relationship recorded by the current node specifically includes: the control center satellite access network gateway node finds the TCP connection of the ground station network gateway node corresponding to the IP address of the edge computing node corresponding to the destination IP address in the received network layer data packet from the routing mapping relationship recorded by the current control center satellite access network gateway node, and sends the processed and packaged data packet to the corresponding ground station network gateway node through the TCP connection of the corresponding ground station network gateway node; In the step S23, sending to the corresponding ground station radio frequency device node according to the routing mapping relationship recorded by the current node specifically includes: the ground station network gateway node finds the TCP connection of the ground station radio frequency device node corresponding to the IP address of the edge computing node corresponding to the destination IP address in the taken-out internal network layer data packet from the routing mapping relationship recorded by the current ground station network gateway node, and sends the processed and packaged data packet to the corresponding ground station radio frequency device node through the TCP connection of the corresponding ground station radio frequency device node.

8. The network communication method applicable to the space-based distributed operating system according to claim 1, wherein The data link layer protocol includes AOS protocol, TM protocol, TC protocol and Prox-1 protocol; The transmission control protocol includes TCP protocol.

9. A network communication device applicable to a space-based distributed operating system, comprising one or more processors and a memory, characterized in that, The memory is coupled to the processor; wherein, the memory is used for storing program data, and the processor is used for executing the program data to implement the network communication method applicable to the space-based distributed operating system according to any one of claims 1-8.

10. A computer-readable storage medium, characterized in that, A program is stored thereon, and when the program is executed by the processor, it is used to implement the network communication method applicable to the space-based distributed operating system according to any one of claims 1-8.

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