Deep space network integrated networking architecture and domain-based networking method, system and equipment

Abstract

The present invention discloses a deep space network fusion networking architecture and a domain-specific networking method, system, and equipment, relating to the technical field of deep space network networking, including: planetary access network nodes in a planetary domain adopt a standard TCP / IP protocol stack, satellite network nodes in the planetary domain adopt a self-organizing networking protocol based on a globally unique identifier, and data aggregation within the planetary domain and cross-planetary domain access are achieved through an interstellar gateway; an interstellar backbone domain uses deep space intelligent routers deployed in a deep space orbit as interstellar backbone network nodes, and transmission between interstellar backbone network nodes is carried out through a deep space fusion protocol, the deep space fusion protocol assigns a unique backbone domain code to each interstellar backbone network node, and maintains a dynamic routing table; cross-domain transmission is carried out between two or more planetary domains through the interstellar backbone domain; the deep space network fusion networking architecture and the domain-specific networking method, system, and equipment realize heterogeneous deep space network fusion and data transmission.

Description

Technical Field

[0001] The present invention relates to the field of deep space network networking technology, and in particular to a deep space network integrated networking architecture and domain-specific networking methods, systems, and devices. Background Art

[0002] The Deep Space Network (DSN) is the space infrastructure supporting deep space exploration missions and a crucial foundation for human interplanetary exploration. Compared to near-Earth satellite networks, the DSN's extreme long-range, high latency, and extremely low bandwidth make its networking and transmission challenging. Compared to near-Earth satellite networks, the DSN relies on extremely low bandwidth for data transmission. Therefore, the DSN's extreme long-range, high latency, and low bandwidth preclude direct reuse of existing near-Earth satellite network routing and transmission technologies. Furthermore, factors such as celestial obstruction and space radiation further reduce the efficiency and reliability of DSN transmission.

[0003] To enhance the data transmission capabilities of deep space exploration missions, deploying multiple deep space interstellar backbone network nodes to connect access networks and deep space exploration equipment on different planets is widely recognized as a future deep space network architecture. The deep space interstellar backbone network provides interplanetary data routing and transmission services, shortening the single-hop communication distance in deep space to a certain extent while reducing link intermittency caused by celestial obstruction. However, deep space networks based on planetary access networks and interstellar backbone networks still face many challenges in terms of efficient routing and transmission. The different networks covered by deep space networks, such as the surface network, planetary access network, and interstellar backbone network, are highly heterogeneous and dynamic, and the development of cross-planetary deep space networking architectures and fusion protocols is urgently needed. Summary of the Invention

[0004] Based on the technical problems existing in the background technology, the present invention proposes a deep space network fusion networking architecture and a domain-based networking method, system and equipment to achieve heterogeneous deep space network fusion and data transmission.

[0005] The deep space network fusion networking architecture and domain-based networking method proposed in the present invention include:

[0006] The planetary access network nodes in the planetary domain use the standard TCP / IP protocol stack, and the satellite network nodes in the planetary domain use the self-organizing network protocol based on the global unique identifier, and realize the data aggregation within the planetary domain and cross-planetary domain access through the interstellar gateway;

[0007] The interstellar backbone domain uses deep space intelligent routers deployed in deep space orbit as interstellar backbone network nodes. The interstellar backbone network nodes transmit information through the deep space fusion protocol. The deep space fusion protocol assigns a unique backbone domain code to each interstellar backbone network node and maintains a dynamic routing table. The entries in the dynamic routing table are indexed by the planet domain code and record the list of reachable interstellar gateways and the link status of the interstellar gateways.

[0008] Cross-domain transmission between two or more planetary domains is achieved through the interstellar backbone domain.

[0009] Furthermore, the TCP / IP protocol is used for routing between the planetary access network nodes and the interstellar gateway, and the deep space fusion protocol is used for routing between the interstellar backbone network nodes in the interstellar backbone domain;

[0010] A protocol conversion module is provided in the interstellar gateway for dynamically mapping TCP / IP addresses and globally unique identifiers of satellite network nodes.

[0011] Furthermore, the identification structure of the dynamic routing table includes a planetary domain code, a backbone domain code, a node type, a subdomain ID, and a globally unique identifier of a satellite network node.

[0012] Furthermore, the header setting of the deep space fusion protocol includes inherent information, address information, cyclic redundancy check code and carried payload;

[0013] The inherent information includes version number, protocol type, service type, payload offset, and payload size;

[0014] The address information includes a source globally unique identifier, a source network address, a destination globally unique identifier, and a destination network address.

[0015] Furthermore, each of the satellite network nodes is assigned a globally unique identifier, which will be transmitted as part of the data packet header. When the data packet arrives at the interstellar backbone network node connected in the interstellar backbone domain, the source globally unique identifier of the satellite network node is extracted from the data packet header. The interstellar backbone network node obtains the destination network address based on it and then forwards the data packet to the next hop.

[0016] Furthermore, the interplanetary gateway is used to achieve data aggregation within the planetary domain and cross-planetary domain access, specifically:

[0017] In the planetary domain, satellite network nodes periodically broadcast beacon messages containing globally unique identifiers. The interstellar gateway estimates the orbital changes of satellite network nodes based on signal strength and Doppler frequency shift, and updates the local identifier-position mapping table in the interstellar gateway, thereby achieving data aggregation within the planetary domain.

[0018] In the cross-planetary domain scenario, in the original planetary domain, the original interstellar gateway marks the globally unique identifier "planetary domain code" field as "transitional state", and pre-registers a temporary identifier with the target planetary domain through the interstellar backbone network node, establishes a bidirectional tunnel to forward traffic until the planetary network node completes the domain switch, thereby realizing cross-planetary domain access.

[0019] Furthermore, the interstellar backbone network nodes adopt a hybrid routing strategy, specifically:

[0020] For delay-sensitive traffic, a source preset path based on a globally unique identifier is used, and the path node coding sequence is injected in advance;

[0021] Use store-and-forward mode for delay-tolerant traffic.

[0022] Furthermore, the topological changes within the planetary domain are encapsulated within the domain, and only the planetary domain code and the interstellar gateway are exposed to the outside.

[0023] Furthermore, it includes an interstellar backbone domain and a planetary domain. The planetary domain includes planetary access network nodes and satellite network nodes orbiting the planet. Inter-domain transmission is achieved between two or more planetary domains through the interstellar backbone domain.

[0024] Planetary access network nodes use the standard TCP / IP protocol stack, and satellite network nodes use a self-organizing network protocol based on a globally unique identifier, achieving data aggregation within the planetary domain and cross-planetary domain access through the interstellar gateway;

[0025] The interstellar backbone domain uses deep space intelligent routers deployed in deep space orbit as interstellar backbone network nodes. The interstellar backbone network nodes are transmitted through the deep space fusion protocol. The deep space fusion protocol assigns a unique backbone domain code to each interstellar backbone network node and maintains a dynamic routing table. The entries in the dynamic routing table are indexed by the planet domain code and record the list of reachable interstellar gateways and the link status of the interstellar gateways.

[0026] A computer device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned method when executing the computer program.

[0027] The advantages of the deep space network fusion networking architecture and domain networking method, system and equipment provided by the present invention are: to address the problem of cross-planetary fusion networking of highly dynamic deep space heterogeneous networks, a globally unique device identifier is introduced, a deep space domain networking architecture with built-in mobility support is proposed, and deep space intelligent routers and interstellar gateways are designed to achieve deep space fusion networking covering star surface networks, planetary access network nodes, interstellar backbone network nodes, and external networks; to address the fusion networking problems caused by the significant heterogeneity and high dynamics of deep space networks, this embodiment introduces a globally unique device identifier, proposes a deep space domain networking architecture with built-in mobility support and an identity-based deep space fusion protocol to achieve heterogeneous deep space network fusion and data transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the process of the present invention;

[0029] Figure 2 This is a schematic diagram of the deep space network architecture;

[0030] Figure 3 This is a diagram of data transmission in the Deep Space Network;

[0031] Figure 4 A schematic diagram of the identification structure of a dynamic routing table;

[0032] Figure 5 This is a schematic diagram of the header of the deep space fusion protocol;

[0033] Figure 6 This is a schematic diagram of the conversion between the deep space fusion protocol and the TCP / IP protocol based on the interstellar gateway. DETAILED DESCRIPTION

[0034] The technical solutions of the present invention are described in detail below through specific embodiments. Numerous specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0035] like Figures 1 to 6 As shown, the deep space network fusion networking architecture and domain-based networking method proposed in the present invention include:

[0036] Step 1: Planetary access network nodes in the planetary domain use the standard TCP / IP protocol stack, and satellite network nodes in the planetary domain use a self-organizing network protocol based on a globally unique identifier, achieving data aggregation within the planetary domain and cross-planetary domain access through the interstellar gateway;

[0037] Step 2: The interstellar backbone domain uses deep space intelligent routers deployed in deep space orbit as interstellar backbone network nodes. The interstellar backbone network nodes are transmitted through the deep space fusion protocol. The deep space fusion protocol assigns a unique backbone domain code to each interstellar backbone network node and maintains a dynamic routing table. The entries in the dynamic routing table are indexed by the planet domain code, and record the list of reachable interstellar gateways and the link status of the interstellar gateways.

[0038] Step 3: Realize cross-domain transmission between two or more planetary domains through the interstellar backbone domain.

[0039] To address the challenges of converged networking caused by the significant heterogeneity and high dynamism of deep space networks, this implementation focuses on the design of a converged deep space network architecture and proposes a deep space domain networking approach based on a Global Unique Identifier (GUID). By establishing a global identity mechanism for deep space nodes, a multi-level networking system is constructed, encompassing the satellite surface sensing layer, planetary access layer, and interstellar backbone layer. Furthermore, addressing the needs of interplanetary network interconnection and overcoming the compatibility limitations of traditional protocol stacks, a cross-domain interoperability framework is designed that supports the convergence of Delay-Tolerant Networking (DTN) and Consultative Committee for Space Data Systems (CCSDS) protocols. This framework focuses on tackling heterogeneous deep space protocol conversion, enabling global interconnection between the deep space network, the terrestrial internet, and planetary surface sensor networks.

[0040] This embodiment also proposes an identity-based deep space fusion protocol to achieve heterogeneous deep space networking integration. Its core lies in the use of globally unique identifiers for routing. Different satellite network nodes are assigned a globally unique identifier, which is transmitted as part of the data packet header. When the data packet reaches the backbone network node in the interstellar backbone domain, it needs to parse the header and extract the source globally unique identifier of the satellite network node from the packet header. The interstellar backbone network node uses this to obtain the destination network address and then forward the data packet to the next hop.

[0041] Based on the mapping between the globally unique identifier of the star network node and the network address, this embodiment further designs the transmission mechanism of the deep space fusion protocol in heterogeneous networks and the conversion between it and the existing protocols.

[0042] In one embodiment, the cross-planet deep space network fusion network architecture design is as follows:

[0043] Deep space networks are subject to dynamic node location changes and communication obstructions. To address this, this embodiment proposes a mobility-supported deep space domain-based networking architecture. This architecture decouples the Global Unique Identifier (GUID) from the Network Address (NA), implementing a domain-specific, spatially distributed GUID-NA resolution system for location management. To address communication interruptions and obstructions, this embodiment deploys a deep space intelligent router and an interplanetary converged gateway to ensure continuous communication.

[0044] Deep space domain networking architecture Figure 2As shown, the basic concept is to apply Internet technology to the planetary access network with lower latency, apply the interstellar backbone network with long latency to connect the distributed planetary access network, and establish an interstellar fusion gateway of low-latency and high-latency networks.

[0045] To meet the needs of highly dynamic, cross-planetary heterogeneous deep space networks, this embodiment addresses the interconnection challenges of long-latency, highly dynamic topologies, and multi-protocol heterogeneous networks in deep space environments through hierarchical domain division, a structured identification system, and dynamic mobility support. This architecture divides deep space networks into three tiers: the planetary domain, the interstellar backbone domain, and the external domain. The planetary domain consists of planetary access network nodes and satellite network nodes orbiting the planet. The planetary access network nodes utilize the standard TCP / IP protocol stack for compatibility with existing ground equipment, while the satellite network nodes employ a globally unique identifier-based self-organizing network protocol, enabling intra-domain data aggregation and cross-domain access through an interstellar gateway.

[0046] As the core node in the planetary domain, the interstellar gateway has a built-in protocol conversion module that can dynamically map TCP / IP addresses and the globally unique identifiers of satellite network nodes (for example, mapping IP 192.168.1.1 to a 128-bit identifier with planetary domain code 0x01 and device type 0x02). At the same time, it maintains the topological state within the planetary domain (that is, the topological changes within the planetary domain are encapsulated within the domain), and only exposes the planetary domain code and interstellar gateway identifier to the outside world, thereby shielding local topological changes caused by satellite orbit migration or ground node movement.

[0047] Since the planetary access network nodes and the interstellar backbone network nodes use different protocols to determine the destination network address, the data forwarding process inevitably involves protocol conversion. Figure 6 As shown, the IP protocol is used between planetary access network nodes and interstellar gateways. After passing through the interstellar gateway, the Deep Space Fusion protocol is used on the way to another interstellar gateway. Only the Deep Space Fusion protocol is used between the routing and forwarding nodes of the interstellar backbone network. The interstellar gateway is responsible for converting between the IP protocol and the Deep Space Fusion protocol. This interstellar gateway-based protocol conversion mechanism effectively compats with traditional IP protocols and improves the scalability of network protocols.

[0048] The interstellar gateway has the following key innovations: 1) Protocol isolation layer: Through the interstellar gateway's protocol conversion module, bidirectional transparent intercommunication between the standard TCP / IP protocol and the deep space fusion protocol is achieved, and surface equipment can access the deep space network of the interstellar backbone domain without modification; 2) Dynamic topology abstraction: Topological changes within the planetary domain (such as satellite orbit adjustments and Mars rover movements) are encapsulated within the domain, and external communications rely only on stable planetary domain coding; 3) Mobility prediction mechanism: Combining Doppler frequency shift and orbit prediction algorithms, the local identity-position mapping table is updated in advance to reduce switching delay.

[0049] This deep space domain networking architecture essentially builds a "deep space coverage network". While maintaining compatibility with existing surface facilities, it solves the core challenges of the deep space environment through structured identification and intelligent routing, laying the foundation for the future interstellar Internet.

[0050] The interstellar backbone domain is composed of deep space intelligent routers deployed in deep space orbit. Its core function is to realize cross-planetary domain routing addressing through structured globally unique identification. Each deep space intelligent router is assigned a unique backbone domain code (16 bits) and maintains a dynamic routing table. The entries in the table are indexed by the planetary domain code (32 bits) to record the list of reachable interstellar gateways and their link status (for example, the Earth domain 0x01 corresponds to the three deep space routers in the orbit of Mars). The identification structure of the dynamic routing table adopts a five-segment 128-bit fixed-length format, including the planetary domain code, backbone domain code, node type (8 bits to distinguish satellite / gateway / probe, etc.), subdomain ID (24 bits to identify the orbital layer or ground subnet) and the globally unique identifier of the satellite network node (48 bits). The identification structure of the dynamic routing table is as follows Figure 4 shown.

[0051] To support cross-domain node mobility, the architecture designs a two-level location management mechanism: within the planetary domain, satellite network nodes periodically broadcast beacon messages containing a globally unique identifier. The interstellar gateway estimates its orbital changes based on signal strength and Doppler frequency shift, and updates the local identifier-location mapping table. In cross-planetary domain scenarios (such as a probe flying from the Earth domain to the Mars domain), the original interstellar gateway marks the "planetary domain code" field of the globally unique identifier as "transitional state" and pre-registers a temporary identifier with the target planetary domain (such as Mars) through the backbone domain router, establishing a bidirectional tunnel to forward traffic until the planetary network node completes the domain switch.

[0052] The deep space intelligent router (interstellar backbone network node) adopts a hybrid routing strategy: it uses identity-based source routing for delay-sensitive traffic (such as telemetry instructions) and injects the path node coding sequence in advance; it adopts the store-and-forward mode for delay-tolerant traffic (such as scientific data).

[0053] For a probe traveling from Earth to Mars, the specific steps for interplanetary domain movement are as follows: 1) Pre-registering a temporary identifier: When the probe leaves the Earth domain, the source Earth interstellar gateway marks the planetary domain code in its globally unique identifier as transitional. It then sends a pre-registration request to the Mars domain via the backbone router, assigning the probe a temporary Mars domain code (pre-registered temporary identifier). 2) A dedicated tunnel is established between the Earth and Mars domains, with the two ends of the tunnel mapping (Earth domain globally unique identifier to Mars domain temporary identifier). After the probe enters the Mars domain, its broadcast beacon is captured by the Mars interstellar gateway, which activates its temporary identifier, updates its routing table, and dismantles the tunnel. Data sent to the probe is encapsulated by the Earth interstellar gateway through the tunnel and forwarded to the Mars interstellar gateway via the interstellar backbone domain. Data sent from the probe is transmitted back to the Earth interstellar gateway via the tunnel by the Mars interstellar gateway, and then returned along the original path.

[0054] In one embodiment, the deep space fusion interconnection protocol message design is specifically as follows:

[0055] This embodiment designs the data packet header of the deep space fusion interconnection protocol as follows Figure 5 As shown, the packet can be divided into four parts: intrinsic information, address information, cyclic redundancy check (CRC), and the payload. The intrinsic information consists of 12 bytes. Excluding the 2-byte reserved field, the remaining 10 bytes are: version number, protocol (protocol type), service type (unicast, multicast, etc.), payload offset, and payload size. Next is the 16-byte address information, which is primarily used for routing. It includes the source unique identifier, source network address, destination unique identifier, and destination network address, each with 4 bytes. The CRC code and the payload are at the end.

[0056] In one embodiment, the deep space fusion protocol transmission mechanism is specifically as follows:

[0057] The network address mapper of the control plane part of the deep space fusion protocol can be used to support the deep space fusion protocol service of the data plane, and find its corresponding network address through the global unique identifier. In the interstellar backbone domain, the destination network address is obtained through the global unique identifier of each satellite network node, and the appropriate planetary access network node is found at the same time. The basic TCP / IP protocol is used for forwarding in each planetary access network node. The transmission process example is as follows Figure 3As shown in the figure, the Earth access network node (planetary access network node) transmits data to the Planet A access network node. Transmission from the Earth access network node (planetary access network node) to Interstellar Gateway N1 and from Interstellar Gateway N2 to the Planet A access network node (planetary access network node) uses only TCP / IP for routing. However, transmission from Interstellar Gateway N1 to Interstellar Gateway N2 uses the Deep Space Fusion protocol for routing (marked by the purple dashed line in the figure). That is, each planetary access network node uses TCP / IP for transmission, while the interstellar backbone network nodes use the Deep Space Fusion protocol for transmission.

[0058] This embodiment addresses the difficulty of cross-planetary fusion networking of highly dynamic deep space heterogeneous networks, introduces a globally unique device identifier, proposes a deep space domain networking architecture with built-in mobility support, designs deep space intelligent routers and interstellar gateways, and realizes deep space fusion networking covering surface networks, planetary access network nodes, interstellar backbone network nodes, and external networks; in response to the fusion networking difficulties caused by the significant heterogeneity and high dynamics of deep space networks, this embodiment introduces a globally unique device identifier, proposes a deep space domain networking architecture with built-in mobility support and an identity-based deep space fusion protocol, to realize heterogeneous deep space network fusion and data transmission.

[0059] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. Deep space network integrated networking architecture and domain-based networking method, characterized by: include: The planetary access network nodes in the planetary domain use the standard TCP / IP protocol stack, and the satellite network nodes in the planetary domain use the self-organizing network protocol based on the global unique identifier, and realize the data aggregation within the planetary domain and cross-planetary domain access through the interstellar gateway; The interstellar backbone domain uses deep space intelligent routers deployed in deep space orbit as interstellar backbone network nodes. The interstellar backbone network nodes transmit information through the deep space fusion protocol. The deep space fusion protocol assigns a unique backbone domain code to each interstellar backbone network node and maintains a dynamic routing table. The entries in the dynamic routing table are indexed by the planet domain code and record the list of reachable interstellar gateways and the link status of the interstellar gateways. Cross-domain transmission between two or more planetary domains is achieved through the interstellar backbone domain; Among them, a protocol conversion module is set in the interstellar gateway, which is used to dynamically map the TCP / IP address and the globally unique identifier of the satellite network node. Each satellite network node is assigned a globally unique identifier, which will be transmitted as part of the data packet header. When the data packet arrives at the interstellar backbone network node connected in the interstellar backbone domain, the source globally unique identifier of the satellite network node is extracted from the data packet header. The interstellar backbone network node obtains the destination network address based on it, and then forwards the data packet to the next hop.

2. The deep space network fusion networking architecture and domain-based networking method according to claim 1 is characterized in that: The identification structure of the dynamic routing table includes a planet domain code, a backbone domain code, a node type, a subdomain ID and a globally unique identifier of a satellite network node.

3. The deep space network fusion networking architecture and domain-based networking method according to claim 1 is characterized in that: The header setting of the deep space fusion protocol includes inherent information, address information, cyclic redundancy check code and carried payload; The inherent information includes version number, protocol type, service type, payload offset, and payload size; The address information includes a source globally unique identifier, a source network address, a destination globally unique identifier, and a destination network address.

4. The deep space network fusion networking architecture and domain-based networking method according to claim 1 is characterized in that: The interstellar gateway is used to achieve data aggregation within the planetary domain and cross-planetary domain access, specifically: In the planetary domain, satellite network nodes periodically broadcast beacon messages containing globally unique identifiers. The interstellar gateway estimates the orbital changes of satellite network nodes based on signal strength and Doppler frequency shift, and updates the local identifier-position mapping table in the interstellar gateway, thereby achieving data aggregation within the planetary domain. In the cross-planetary domain scenario, in the original planetary domain, the original interstellar gateway marks the globally unique identifier "planetary domain code" field as "transitional state", and pre-registers a temporary identifier with the target planetary domain through the interstellar backbone network node, establishes a bidirectional tunnel to forward traffic until the planetary network node completes the domain switch, thereby realizing cross-planetary domain access.

5. The deep space network fusion networking architecture and domain-based networking method according to claim 1 is characterized in that: The interstellar backbone network nodes adopt a hybrid routing strategy, specifically: For delay-sensitive traffic, a source preset path based on a globally unique identifier is used, and the path node coding sequence is injected in advance; Use store-and-forward mode for delay-tolerant traffic.

6. The deep space network fusion networking architecture and domain-based networking method according to claim 1 is characterized in that: The internal topological changes of the planetary domain are encapsulated within the domain, and only the planetary domain code and the interstellar gateway are exposed to the outside.

7. Deep space network integrated networking architecture and domain networking system, characterized by: It includes the interstellar backbone domain and the planetary domain. The planetary domain includes the planetary access network nodes and the satellite network nodes orbiting the planet. Inter-domain transmission is achieved between two or more planetary domains through the interstellar backbone domain. Planetary access network nodes use the standard TCP / IP protocol stack, and satellite network nodes use a self-organizing network protocol based on a globally unique identifier, achieving data aggregation within the planetary domain and cross-planetary domain access through the interstellar gateway; The interstellar backbone domain uses deep space intelligent routers deployed in deep space orbit as interstellar backbone network nodes. The interstellar backbone network nodes transmit information through the deep space fusion protocol. The deep space fusion protocol assigns a unique backbone domain code to each interstellar backbone network node and maintains a dynamic routing table. The entries in the dynamic routing table are indexed by the planet domain code and record the list of reachable interstellar gateways and the link status of the interstellar gateways. Among them, a protocol conversion module is set in the interstellar gateway, which is used to dynamically map the TCP / IP address and the globally unique identifier of the satellite network node. Each satellite network node is assigned a globally unique identifier, which will be transmitted as part of the data packet header. When the data packet arrives at the interstellar backbone network node connected in the interstellar backbone domain, the source globally unique identifier of the satellite network node is extracted from the data packet header. The interstellar backbone network node obtains the destination network address based on it, and then forwards the data packet to the next hop.

8. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method according to any one of claims 1 to 6 is implemented.

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