Network node and communication method

Abstract

This network node comprises: a reception unit for receiving a first message that includes routing information, including the Internet Protocol (IP) address of a counterpart terminal as well as the physical address and the IP address of a router, from a source first network node for processing user data; and a transmission unit for transmitting a second message that includes the routing information to a destination second network node for processing the user data.

Description

Network node and communication method

[0001] The present invention relates to a network node in a communication system and a communication method.

[0002] 3GPP (registered trademark) (3rd Generation Partnership Project) is currently studying a wireless communication system called 5G or NR (New Radio) (hereinafter, the wireless communication system will be referred to as "5G" or "NR") in order to achieve a larger system capacity, a higher data transmission speed, and a lower latency in wireless sections. Various wireless technologies are being studied for 5G to meet the requirements of achieving a throughput of 10 Gbps or more while keeping latency in wireless sections to 1 ms or less.

[0003] In NR, a network architecture including 5GC (5G Core Network) corresponding to EPC (Evolved Packet Core), which is the core network in the network architecture of LTE (Long Term Evolution), and NG-RAN (Next Generation - Radio Access Network) corresponding to E-UTRAN (Evolved Universal Terrestrial Radio Access Network), which is the RAN (Radio Access Network) in the network architecture of LTE, is being considered (for example, Non-Patent Document 1).

[0004] Furthermore, as an IMS (IP Multimedia Subsystem) architecture that supports the data channel capabilities of terminals, specifications for an IMS data channel network are being studied (see, for example, Non-Patent Document 2). In the IMS data channel network, a Data Channel Signalling Function (DCSF) having a signaling function, a Media Function (MF) having a media-related function, and a Data Channel Application Server (DCAS) that is an application server are arranged on both the calling and called sides.

[0005] Furthermore, in 3GPP Rel-19, in order to realize IMS voice terminal-satellite-terminal communication (UE-satellite-UE communication), reducing the impact on existing specifications when deploying 5GC network functions and IMS components on satellites is an issue (see, for example, Non-Patent Document 3). Here, terminal-satellite-terminal communication refers to terminal-to-terminal communication under routing that keeps user plane traffic within the satellite. The types of satellites handled include geostationary satellites (GEO), low Earth orbit satellites (LEO), and medium Earth orbit satellites (MEO). Furthermore, for low Earth orbit satellites and medium Earth orbit satellites, satellite constellations can be formed without using inter-satellite links (ISLs) or using inter-satellite links.

[0006] 3GPP TS 23.501 V18.4.0 (2023-12) 3GPP TS 23.228 V18.4.0 (2023-12) 3GPP TR 23.700-29 V0.4.0 (2024-03) 3GPP TS 38.331 V18.0.0 (2023-12) 3GPP TS 38.413 V18.0.0 (2023-12) 3GPP TS 29.502 V18.5.0 (2023-12)

[0007] In terminal-satellite-terminal communications, for example, when a satellite constellation is formed using inter-satellite links in low-earth orbit satellites, communication devices such as a base station and a user plane function (UPF) are installed on each satellite.

[0008] However, in a case where voice communication is carried out between two terminals under different satellites without an IMS access gateway, when one satellite is switched to another satellite, the existing specifications do not allow the UPF address to be switched appropriately.

[0009] The present invention has been made in view of the above points, and has as its object to appropriately switch the address of a user plane function when switching satellites in a wireless communication system.

[0010] According to the disclosed technology, there is provided a network node having a receiving unit that receives a first message including routing information including an IP (Internet Protocol) address of an opposing terminal and a physical address and IP address of a router from a first network node at a source of movement that processes user data, and a transmitting unit that transmits a second message including the routing information to a second network node at a destination of movement that processes the user data.

[0011] According to the disclosed technology, in a wireless communication system, the address of a user plane function can be appropriately switched when switching satellites.

[0012] FIG. 1 is a diagram for explaining an example of a communication system. FIG. 2 is a diagram for explaining an example of a communication system in a roaming environment. FIG. 3 is a diagram for explaining an example of an IMS data channel network. FIG. 4 is a diagram showing an example of a first sequence diagram in an embodiment of the present invention. FIG. 5 is a diagram showing an example of a second sequence diagram in an embodiment of the present invention. FIG. 6 is a diagram showing an example of a third sequence diagram in an embodiment of the present invention. FIG. 7 is a diagram showing an example of a fourth sequence diagram in an embodiment of the present invention. FIG. 8 is a diagram showing an example of the functional configuration of a base station 10 and a network node 30 in an embodiment of the present invention. FIG. 9 is a diagram showing an example of the functional configuration of a terminal 20 in an embodiment of the present invention. FIG. 10 is a diagram showing an example of the hardware configuration of a base station 10, a terminal 20, and a network node 30 in an embodiment of the present invention. FIG.

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0014] In the operation of the wireless communication system according to the embodiment of the present invention, existing technology is used as appropriate. However, the existing technology is, for example, the existing LTE, but is not limited to the existing LTE. Furthermore, the term "LTE" used in this specification has a broad meaning including LTE-Advanced, and systems subsequent to LTE-Advanced (e.g., NR), or wireless LAN (Local Area Network), unless otherwise specified.

[0015] Furthermore, in the embodiments of the present invention, "configuring" radio parameters and the like may mean that predetermined values ​​are pre-configured, or that radio parameters notified from the network node 30 or the terminal 20 are set.

[0016] Fig. 1 is a diagram illustrating an example of a communication system. As shown in Fig. 1, the communication system is composed of a UE, which is a terminal 20, and multiple network nodes 30. Hereinafter, it is assumed that one network node 30 corresponds to each function, but multiple functions may be realized by one network node 30, or multiple network nodes 30 may realize one function. Furthermore, the "connection" described below may be a logical connection or a physical connection.

[0017] The RAN (Radio Access Network) is a network node 30 having a radio access function, which may include a base station 10, and is connected to a UE, an AMF (Access and Mobility Management Function), and a UPF (User Plane Function). The AMF is a network node 30 having functions such as terminating the RAN interface, terminating the NAS (Non-Access Stratum), registering management, connecting management, reachability management, and terminal mobility management. The UPF is a network node 30 having functions related to processing user plane data, such as a PDU (Protocol Data Unit) session point to the outside that interconnects with the DN (Data Network), packet routing and forwarding, and user plane Quality of Service (QoS) handling. The UPF and the DN constitute a network slice. In the wireless communication network according to the embodiment of the present invention, multiple network slices are constructed.

[0018] The AMF is connected to the UE, RAN, SMF (Session Management function), NSSF (Network Slice Selection Function), NEF (Network Exposure Function), NRF (Network Repository Function), UDM (Unified Data Management), AUSF (Authentication Server Function), PCF (Policy Control Function), and AF (Application Function). The AMF, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, and AF are network nodes 30 that are mutually connected via interfaces based on their respective services, Namf, Nsmf, Nnssf, Nnef, Nnrf, Nudm, Nausf, Npcf, and Naf.

[0019] The SMF is a network node 30 having functions such as session management, UE IP (Internet Protocol) address allocation and management, DHCP (Dynamic Host Configuration Protocol) function, ARP (Address Resolution Protocol) proxy, and roaming function. The NEF is a network node 30 having a function of notifying other NFs (Network Functions) of capabilities and events. The NSSF is a network node 30 having functions such as selecting a network slice to which a UE connects, determining an allowed NSSAI (Network Slice Selection Assistance Information), determining an NSSAI to be set, and determining an AMF set to which a UE connects. The PCF is a network node 30 having a function of controlling network policies. The AF is a network node 30 having a function of controlling application servers. The NRF is a network node 30 having a function of discovering NF instances that provide services. The UDM is a network node 30 that manages subscriber data and authentication data. The UDM is connected to a UDR (User Data Repository) that stores the data.

[0020] Fig. 2 is a diagram illustrating an example of a communication system in a roaming environment. As shown in Fig. 2, the network is composed of a UE, which is a terminal 20, and multiple network nodes 30. Hereinafter, it is assumed that one network node 30 corresponds to each function, but multiple functions may be realized by one network node 30, or multiple network nodes 30 may realize one function. Furthermore, the "connection" described below may be a logical connection or a physical connection.

[0021] The RAN is a network node 30 having a radio access function, and is connected to the UE, the AMF, and the UPF. The AMF is a network node 30 having functions such as RAN interface termination, NAS termination, registration management, connection management, reachability management, and mobility management. The UPF is a network node 30 having functions such as a PDU session point to the outside that interconnects with the DN, packet routing and forwarding, and user plane QoS handling. The UPF and the DN constitute a network slice. In the wireless communication network according to the embodiment of the present invention, multiple network slices are constructed.

[0022] The AMF is connected to the UE, RAN, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, AF, and SEPP (Security Edge Protection Proxy). The AMF, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, and AF are network nodes 30 that are interconnected via respective service-based interfaces, Namf, Nsmf, Nnssf, Nnef, Nnrf, Nudm, Nausf, Npcf, and Naf.

[0023] The SMF is a network node 30 having functions such as session management, UE IP address allocation and management, DHCP function, ARP proxy, and roaming function. The NEF is a network node 30 having a function of notifying other NFs of capabilities and events. The NSSF is a network node 30 having functions such as selecting a network slice to which a UE connects, determining an allowed NSSAI, determining a configured NSSAI, and determining an AMF set to which a UE connects. The PCF is a network node 30 having a function of controlling network policies. The AF is a network node 30 having a function of controlling application servers. The NRF is a network node 30 having a function of discovering NF instances that provide services. The SEPP is a non-transparent proxy that filters control plane messages between PLMNs (Public Land Mobile Networks). The vSEPP shown in FIG. 2 is a SEPP in the visited network, and the hSEPP is a SEPP in the home network.

[0024] As shown in Figure 2, a UE is in a roaming environment connected to a RAN and an AMF in a Visited PLMN (VPLMN). The VPLMN and a Home PLMN (HPLMN) are connected via a vSEPP and an hSEPP. The UE can communicate with a UDM in the HPLMN via the AMF in the VPLMN, for example.

[0025] Fig. 3 is a diagram illustrating an example of an IMS data channel network. As shown in Fig. 3, the IMS data channel network is configured with a terminal 20 (UE) and multiple network nodes 30 in each of an originating network and a terminating network. Hereinafter, it is assumed that one network node 30 corresponds to each function, but multiple functions may be realized by one network node 30, or multiple network nodes 30 may realize one function. Furthermore, the "connection" described below may be a logical connection or a physical connection. The network node 30 has, for example, the following functions described in Non-Patent Document 2:

[0026] The IMS-AGW (Access Gateway) is a network node 30 having a gateway function between the UE and the IMS network, a function related to access processing for voice communication, and the like.

[0027] A P-CSCF (Proxy-Call Session Control Function) is a network node 30 that has a proxy function between the UE and the IMS network, an access control function for voice communication, and the like.

[0028] The S-CSCF (Serving-Call Session Control Function) is a network node 30 having functions related to session control for the UE.

[0029] The I-CSCF (Interrogate-Call Session Control Function) is a connection point on the destination network side between networks (e.g., between the source network side and the destination network side) in the IMS network, and is a network node 30 that has, for example, the function of forwarding a received SIP request to the S-CSCF of its own network.

[0030] An IMS AS (IP Multimedia Subsystem Application Server) is a network node 30 in an IMS network that has functions such as communicating with a DCSF for event notification and receiving data channel control instructions from the DCSF to communicate with an MF. The IMS AS also receives a communication termination point registration request from a DCSF (Data Channel Signalling Function), converts the received registration request into a SIP Register, and sends it to a Serving-Call Session Control Function (S-CSCF). The IMS AS also converts a data channel establishment request received from the DCSF into a SIP INVITE and sends it to the S-CSCF.

[0031] The DCSF (Data Channel Signaling Function) is a network node 30 that has functions such as receiving an event report from the IMS-AS and determining whether to allow the provision of a data channel service, managing the bootstrap data channel, and performing HTTP web server functions.

[0032] An MF (Media Function) is a network node 30 in an IMS network that has functions such as media resource management and forwarding of data channel media traffic. The MF processes media between a DCAS (Data Channel Application Server), which is a communication termination point, and a destination termination point based on configuration information received from a DCSF. The MF may also be called a DCMF (Data Channel Media Function). The MF may also be called an MRF (Multimedia Resource Function).

[0033] A DCAS (Data Channel Application Server) is a network node 30 having functions such as a communication termination point for media and signaling in the IMS network.

[0034] In this embodiment, it is assumed that a plurality of low-earth orbit satellites (LEOs) equipped with base stations and UPFs form a satellite constellation using inter-satellite links (ISLs). In addition, N2 Intermediaries and N4 Intermediaries are deployed on the ground as intermediary devices that communicate with the devices deployed in the LEOs.

[0035] The N2 intermediary performs communication with the base station and communication with the AMF based on the interface (N2) between the base station and the AMF, i.e., the N2 intermediary acts as an AMF to the base station and as a base station to the AMF.

[0036] The N4 Intermediary communicates with the UPF and the SMF based on the interface (N4) between the UPF and the SMF, i.e., the N4 Intermediary acts as an SMF to the UPF and as a UPF to the SMF.

[0037] The intermediary device and the terminal connect to different LEOs depending on the time based on the satellite ephemeris, which is information indicating the relationship between the position of a satellite in its orbit and time.

[0038] Satellite communications operators mainly prepare base stations and UPFs deployed in LEO and intermediate devices deployed on the ground as dedicated equipment for satellite constellation communications, while mobile communications operators mainly prepare AMFs and SMFs, which are network nodes deployed on the ground, as satellite constellation utilization equipment.

[0039] In this embodiment, the following procedure is performed to properly switch the address of the user plane function when switching satellites.

[0040] Assume that satellite A accommodates terminal 20A, and satellite B accommodates terminal 20B.

[0041] The IP packet transmitted by terminal 20A is sent from UPF 30A accommodating the PDU session of terminal 20A, received by UPF 30A2 accommodating the PDU session of terminal 20B, and transmitted to terminal 20B. Here, UPF 30A assigns the MAC address (physical address) of UPF 30A2 to the IP packet.

[0042] Next, satellite B2 accommodates terminal 20B instead of satellite B. UPF 30A3 accommodates the PDU session of terminal 20B instead of UPF 30A2. UPF 30A needs to assign the MAC address of UPF 30A3 to IP packets. However, under existing specifications, UPF 30A cannot obtain the MAC address of UPF 30A3 at the time of switching from satellite B to satellite B2.

[0043] The details of the processing in this embodiment will be explained below using sequence diagrams. Requests, responses, notifications, etc. sent and received in the procedures shown below may be called messages (e.g., request messages). For details of existing specifications related to messages sent and received in this sequence diagram, see Non-Patent Documents 4-6, etc.

[0044] In this embodiment, a network accommodating terminal 20A making a voice call is referred to as a source network, and a network accommodating terminal 20B making a voice call is referred to as a destination network. Furthermore, for example, from the perspective of the source network, terminal 20B may be referred to as an opposed terminal, and terminal 20A may be referred to as an accommodated terminal. Similarly, from the perspective of the destination network, terminal 20A may be referred to as an opposed terminal, and terminal 20B may be referred to as an accommodated terminal. Furthermore, for example, information including the IP address of a destination terminal and the IP address and MAC address of a router to which user data addressed to that terminal is to be sent may be referred to as routing information.

[0045] (IMS PDU Session Establishment Procedure) The IMS PDU session establishment procedure in this embodiment will be described in detail using a sequence diagram. Fig. 4 is a diagram showing an example of a first sequence diagram in the embodiment of the present invention. The processing of each step will be described below.

[0046] S101: The terminal 20A transmits a request message for PDU session establishment to the base station 10. The request message includes information indicating the PDU session establishment request and information related to the Data Network Name (DNN), and is expressed as, for example, ULInformationTransfer(dedicatedNAS-Message(UL NAS transport(Payload container type(N1 SM information), Payload container(PDU Session Establishment request), DNN=ims))).

[0047] S102: The base station 10 sends a request message for PDU session establishment to the N2 intermediary 30B. The request message includes information indicating the PDU session establishment request and information about the DNN, and is expressed as, for example, Uplink NAS Transport(NAS-PDU(UL NAS transport(Payload container type(N1 SM information), Payload container(PDU Session Establishment request), DNN=ims))).

[0048] S103: The N2 intermediary 30B sends the request message (Uplink NAS Transport) received in S102 to the AMF 30D.

[0049] S104: The AMF 30D recognizes that the request is from the terminal 20A under the satellite constellation (ID (identifier) ​​= aa) based on the base station identifier corresponding to the N2 intermediary 30B.

[0050] S105: The AMF 30D sends a request message for establishing a PDU session to the SMF 30E. The request message includes the identifier (ID=aa) of the satellite constellation recognized in S103, information about the DNN, and information indicating the PDU session establishment request, and is expressed as, for example, Nsmf_PDUSession_CreateSMContext request (SmContextCreateData (Dnn=ims, n1SmMsg (PDU session establishment request), satellite constellation ID=aa)).

[0051] S106: SMF30E sends a response message (Nsmf_PDUSession_CreateSMContext response) to the request message received in S105 to AMF30D.

[0052] S107: The SMF 30E sends a request message (Npcf_SMPolicyControl_Create request) for creating a session management policy to the PCF 30F. The request message includes a PDU session identifier and is expressed as, for example, Npcf_SMPolicyControl_Create request (SmPolicyContextData (pduSessionId)).

[0053] S108: The PCF 30F sends the SMF 30E a response message (Npcf_SMPolicyControl_Create response) in response to the request message received in S107.

[0054] S109: The SMF 30E selects the N4 intermediary corresponding to the satellite constellation (ID=aa).

[0055] S110: The SMF 30E decides to include a PDU session identifier in the message to be transmitted in order to facilitate operation within the satellite.

[0056] S111: When assigning an IP address to the terminal 20A that uses a satellite, the SMF 30E assumes that the address will be assigned from the IP address range for the satellite constellation (ID=aa). In addition, the SMF 30F determines to transmit the IP address assigned to the terminal 20A to the UPF 30A.

[0057] S112: The SMF 30E sends a request message (Npcf_SMPolicyControl_Update request) to the PCF 30F to update the session management policy. The request message includes the IP addresses associated with IPv4 and IPv6 assigned to the terminal 20A, and is expressed as, for example, Npcf_SMPolicyControl_Update request (SmPolicyUpdateContextData(ipv4Address, ipv6AddressPrefix)).

[0058] S113: The PCF 30F sends to the SMF 30E a response message (Npcf_SMPolicyControl_Update response) in response to the request message received in S112.

[0059] S114: The SMF 30E transmits a request message (PFCP Session Establishment request) for establishing a user data transfer path to the N4 intermediary 30C. The request message includes a PDU session identifier and the IP address of the terminal 20A.

[0060] S115: The N4 intermediary 30C selects a UPF 30A based on a list of a set of a start time, an end time, and a destination UPF, which is created with reference to the satellite ephemeris.

[0061] S116: The N4 intermediary 30C sends a request message (PFCP Session Establishment request) for establishing a user data transfer path to the UPF 30A. The request message includes a PDU session identifier and the IP address of the terminal 20A.

[0062] S117: UPF 30A stores the PDU session identifier received in S116 in the context.

[0063] S118: The UPF 30A stores the IP address of the terminal 20A received in S116 in the context. The IP address may be stored in association with the PDU session identifier received in S116.

[0064] S119: The UPF 30A transmits a response message (PFCP Session Establishment response) to the request message received in S116 to the N4 intermediary 30C. The response message includes the node identifier of the UPF 30A.

[0065] S120: The N4 intermediary 30C transmits to the SMF 30E a response message (PFCP Session Establishment response) in response to the request message received in S114. The response message includes the node identifier of the UPF 30A.

[0066] S121: The SMF 30E sends a request message (Npcf_SMPolicyControl_Update request) to the PCF 30F to update the session management policy. The request message includes the node identifier of the UPF 30A received in S120, and is expressed as, for example, Npcf_SMPolicyControl_Update request (SmPolicyUpdateContextData(UPF Node ID)).

[0067] S122: The PCF 30F stores the node identifier of the UPF 30A in the context.

[0068] S123: The PCF 30F sends to the SMF 30E a response message (Npcf_SMPolicyControl_Update response) in response to the request message received in S121.

[0069] S124: SMF 30E stores the IP address (= bb) of the (terrestrially deployed) satellite P-CSCF. SMF 30E also determines that a special P-CSCF that can handle the IMS AGW is required and determines to set the IP address (= bb) as the P-CSCF address of ePCO (extended Protocol Configuration Options).

[0070] S125: The SMF 30E transmits a message including information indicating acceptance of the PDU session establishment request to the AMF 30D. The message also includes the IP address of the terminal 20A and the IP address (=bb) of the P-CSCF, and is expressed as, for example, Namf_Communication_N1N2MessageTransfer (N1N2MessageTransferReqData(n1MessageContainer(PDU Session Establishment accept (PDU address=terminal address, Extended protocol configuration options(P-CSCF address=bb))), n2InfoContainer(PDU Session Resource Setup Request Transfer))).

[0071] S126: The AMF 30G transmits a request message (PDU Session Resource Setup Request) for setting up a PDU session resource to the N2 intermediary 30B. The message includes the IP address of the terminal 20A and the IP address (=bb) of the P-CSCF, and is expressed as, for example, PDU Session Resource Setup Request (NAS-PDU (DL NAS transport (Payload container type (N1 SM information), Payload container (PDU Session Establishment accept (PDU address = terminal address, Extended protocol configuration options (P-CSCF address = bb))))), PDU Session Resource Setup Request List (PDU Session Resource Setup Request Transfer)).

[0072] S127: The N2 intermediary 30B transmits the request message (PDU Session Resource Setup request) received in S126 to the base station 10.

[0073] S128: The base station 10 transmits a message including information indicating acceptance of the PDU session establishment request to the terminal 20A. The message also includes the IP address of the terminal 20A and the IP address (=bb) of the P-CSCF, and is expressed as, for example, RRCReconfiguration(dedicatedNAS-Message(DL NAS transport(Payload container type(N1 SM information), Payload container(PDU Session Establishment accept(PDU address=terminal address, Extended protocol configuration options(P-CSCF address=dd)))))).

[0074] (Voice Call Procedure) The voice call procedure in this embodiment will be described in detail using a sequence diagram. Fig. 5 is a diagram showing an example of a second sequence diagram in the embodiment of the present invention. The processing of each step will be described below.

[0075] S201: The terminal 20A transmits a message (SIP INVITE) requesting a voice call to the P-CSCF 30G. The message includes the IP address of the terminal 20A in the setting information (SDP offer).

[0076] S202: The P-CSCF 30G transmits the message (SIP INVITE) received in S201 requesting the voice call to the P-CSCF 30H of the destination network.

[0077] S203: The P-CSCF 30H transmits the message (SIP INVITE) received in S202 requesting the voice call to the terminal 20B.

[0078] S204: The terminal 20B transmits a response message (SIP 183 Session Progress) indicating that voice communication is being set up to the P-CSCF 30H. The message includes the IP address of the terminal 20B in the setting information (SDP answer).

[0079] S205: The P-CSCF 30H sends a request message (Npcf_PolicyAuthorization_Create request) to the PCF 30J to set up a QoS flow for transmitting voice media. The request message includes information indicating a request for the node identifier of the UPF (UPF 30A2) on the destination network side. The UPF (UPF 30A2) is a network node that routes voice communication media to the terminal 20B.

[0080] S206: The PCF 30J transmits to the P-CSCF 30H a response message (Npcf_PolicyAuthorization_Create response) in response to the request message received in S205. The response message includes the node identifier of the UPF (UPF 30A2) on the destination network side.

[0081] Between S206 and S207, a procedure for PDU session change processing based on existing specifications is executed.

[0082] S207: The P-CSCF30H transmits a response message (SIP 183 Session Progress) from the destination network, indicating that voice communication is being set up, to the P-CSCF30G of the source network. The response message includes, in the setting information (SDP answer), the IP address of the terminal 20B and the node identifier of the UPF (UPF30A2) of the destination network as the node identifier of the router of the destination network, and is expressed as, for example, SIP 183 Session Progress (SDP answer (c=IP address of the terminal 20B, a=node ID of the router of the destination network (=UPF Node ID of UPF30A2))).

[0083] S208: The P-CSCF 30G sends a request message (Npcf_PolicyAuthorization_Create request) to the PCF 30F to set up a QoS flow for transmitting voice media. The request message includes information indicating a node identifier request to the UPF (UPF 30A) of the source network and the contents to be set in the context in the UPF (UPF 30A) of the source network (the IP address of the terminal 20B and the node identifier of the UPF (UPF 30A2) of the destination network as the node identifier of the router of the destination network). The UPF (UPF 30A2) is a network node that routes voice communication media to the terminal 20B.

[0084] S209: The PCF 30F transmits a response message (Npcf_PolicyAuthorization_Create response) to the request message received in S208 to the P-CSCF 30G. The response message includes the node identifier of the UPF (UPF 30A) of the source network.

[0085] S210: The PCF 30F identifies the IP address and MAC address of the node from the node identifier of the router in the destination network. Alternatively, the PCF 30F may obtain the IP address and MAC address of the node from the NRF in the destination network.

[0086] S211: The PCF 30F sends a request message (Npcf_SMPolicyControl_UpdateNotify request) to the SMF 30E to update the session management policy. The request message includes the IP address of the terminal 20B and the IP address and MAC address of the router in the destination network as routing information to be set in the UPF (UPF 30A) context of the source network. For example, the response message is expressed as Npcf_SMPolicyControl_UpdateNotify request (UPF context setting contents (IP address of terminal 20B, IP address and MAC address of the router in the destination network)).

[0087] S212: The SMF 30E sends to the PCF 30F a response message (Npcf_SMPolicyControl_UpdateNotify response) in response to the request message received in S211.

[0088] S213: The SMF 30E transmits a request message (PFCP Session Modification request) for modifying the user data transfer path to the N4 intermediary 30B. The request message includes the IP address of the terminal 20B and the IP address and MAC address of the router in the destination network as contents to be set in the UPF (UPF 30A) context of the source network.

[0089] S214: The N4 intermediary 30B transmits the request message (PFCP Session Modification request) received in S213 to the UPF 30A.

[0090] S215: The UPF 30A stores the IP address of the terminal 20B and the IP address and MAC address of the router in the destination network in the context and the setting of the N6 interface exit.

[0091] S216: The UPF 30A sends a response message (PFCP Session Modification response) to the request message received in S214 to the N4 intermediary 30B.

[0092] S217: The N4 intermediary 30B sends to the SMF 30E a response message (PFCP Session Modification response) to the request message received in S213.

[0093] Between S217 and S218, a procedure for PDU session change processing based on existing specifications is executed.

[0094] S218: The P-CSCF 30G transmits a response message (SIP 183 Session Progress) from the destination network to the terminal 20A. The response message includes the IP address of the terminal 20B in the setting information (SDP answer).

[0095] S219: The terminal 20A transmits a message (PRACK / UPDATE) to the P-CSCF 30G requesting an update of the setting information of the voice communication path. The message includes the IP address of the terminal 20A in the setting information (SDP offer).

[0096] S220: The P-CSCF30G sends a message (PRACK / UPDATE) to the P-CSCF30H of the destination network, requesting an update of the voice communication path setting information. The message includes, in the setting information (SDP offer), the IP address of the terminal 20A and the node identifier of the UPF (UPF30A) of the source network as the node identifier of the router of the source network, and is expressed as, for example, PRACK / UPDATE(SDP offer(c=IP address of the terminal 20A, a=node ID of the router of the source network (=UPF Node ID of UPF30A))).

[0097] The process following S220 will be described. Fig. 6 is a diagram showing an example of a third sequence diagram according to an embodiment of the present invention. The process of each step will be described below.

[0098] S221: P-CSCF30H sends a request message (Npcf_PolicyAuthorization_Update request) to PCF30J for updating the QoS flow setting for transmitting voice media. The request message includes the contents to be set in the context in the destination network UPF (UPF20A2) (the IP address of terminal 20A and the node identifier of the source network UPF (UPF30A) as the node identifier of the source network router), and is expressed as, for example, Npcf_PolicyAuthorization_Update request (UPF context setting contents (IP address of terminal 20A, node ID of NW1 router (=UPF Node ID of UPF30A))).

[0099] S222: The PCF 30J transmits to the P-CSCF 30H a response message (Npcf_PolicyAuthorization_Update response) in response to the request message received in S221.

[0100] S223: The PCF 30J derives the IP address and MAC address of the node from the node identifier of the router in the source network. Alternatively, the PCF 30J may obtain the IP address and MAC address of the node from the NRF in the source network.

[0101] S224: The PCF 30J sends a request message (Npcf_SMPolicyControl_UpdateNotify request) to the SMF 30K to notify the SMF 30K of the update of the session management policy. The request message includes the IP address of the terminal 20A and the IP address and MAC address of the router in the source network as the contents to be set in the UPF (UPF 30A2) context of the destination network.

[0102] S225: The SMF 30K sends to the PCF 30J a response message (Npcf_SMPolicyControl_UpdateNotify response) in response to the request message received in S224.

[0103] S226: The SMF 30K sends a request message (PFCP Session Modification request) to the N4 intermediary 30F to modify the user data transfer path. The request message includes the IP address of the terminal 20A and the IP address and MAC address of the router in the source network as content to be set in the UPF (UPF 30A2) context of the destination network.

[0104] S227: The N4 intermediary 30F sends a request message (PFCP Session Modification request) to the UPF 30A2 to modify the user data transfer path. The request message includes the IP address of the terminal 20A and the IP address and MAC address of the router in the source network as the contents to be set in the UPF (UPF 30A2) context of the destination network.

[0105] S228: The UPF 30A2 stores the IP address of the terminal 20A and the IP address and MAC address of the router in the source network in the context and the setting of the N6 interface exit.

[0106] S229: The UPF 30A2 transmits a response message (PFCP Session Modification response) to the request message received in S227 to the N4 intermediary 30F.

[0107] S230: The N4 intermediary 30F sends a response message (PFCP Session Modification response) to the request message received in S226 to the SMF 30K.

[0108] S231: The P-CSCF 30H transmits a message (PRACK / UPDATE) requesting an update of the setting information of the voice communication path to the terminal 20B. The message includes the IP address of the terminal 20A in the setting information (SDP offer).

[0109] S232: UPF 30A transfers the audio media sent from terminal 20A to UPF 30A2, which then transfers it to terminal 20B. Here, UPF 30A may transfer the audio media to UPF 30A2 using the MAC address of UPF 30A2, which corresponds to a router in the destination network, or may transfer the audio media using the IP address of UPF 30A2 after encapsulating it using IPSec or the like.

[0110] S233: UPF 30A2 transfers the audio media sent from terminal 20B to UPF 30A, and UPF 30A further transfers it to terminal 20A. Here, UPF 30A2 may transfer the audio media to UPF 30A using the MAC address of UPF 30A, which corresponds to a router in the source network, or may encapsulate the audio media using IPSec or the like and then use the IP address of UPF 30A.

[0111] (UPF Switching Procedure) The UPF switching procedure in this embodiment will be described in detail using a sequence diagram. Figure 7 is a diagram showing an example of a fourth sequence diagram in an embodiment of the present invention. In this sequence diagram, as the destination satellite is switched, the user plane function (UPF) switches from UPF 30A2 in the source satellite to UPF 30A3 in the destination satellite. The processing of each step will be described below.

[0112] S301: The inter-satellite cooperation NF 30R of the destination node transmits a request message to the inter-satellite cooperation NF 30Q of the source node to acquire a UPF context for RAN. The request message includes a PDU session identifier. The PDU session identifier may be used to identify the context in the request message (the same applies to the following steps).

[0113] S302: The inter-satellite cooperation NF 30Q transmits a first request message and a second request message to the UPF 30A2 for acquiring a UPF context for the RAN.

[0114] The first request message includes a UL context associated with the PDU session identifier (i.e., the F-SEID (Fully Qualified - Session Endpoint Identifier) ​​corresponds to the ID for the uplink (UL) between the source UPF 30A and the source base station 10) and a request for the IP address of the terminal 20B.

[0115] The second request message includes the DL context associated with the PDU session identifier (i.e., the F-SEID (Fully Qualified - Session Endpoint Identifier) ​​corresponds to the ID for the downlink (DL) between the source UPF 30A and the source base station 10), a request for the IP address of the terminal 20B, and a request for the IP address and MAC address of the source router (i.e., UPF 30A2).

[0116] S303: The UPF 30A2 transmits, to the inter-satellite link NF 30Q, a first response message and a second response message in response to the first request message and the second request message received in S302, respectively.

[0117] The first response message includes the IP address of terminal 20A and the IP address and MAC address of the router in the source network (i.e., UPF 20A) as the context of the UL route between source UPF 20A2 and source base station 10. The first response message also includes the IP address of terminal 200B.

[0118] The second response message includes the context of the DL route between the source UPF 20A2 and the source base station 10, the IP address of the terminal 20B, and the IP address and MAC address of the source router (that is, the UPF 30A2).

[0119] S304: The inter-satellite cooperation NF 30Q transmits a response message to the request message received in S301 to the inter-satellite cooperation NF 30R. The response message includes, as a context within the source UPF 30A, the IP address of the terminal 20A and the IP address and MAC address of the router in the source network (i.e., UPF 30A). The response message also includes the IP address of the terminal 20B and the IP address and MAC address of the router in the source destination network (i.e., UPF 30A2).

[0120] S305: The inter-satellite cooperation NF 30R transmits a first request message and a second request message for setting a UPF context for RAN to the UPF 30A3.

[0121] The first request message includes the IP address of terminal 20A, the IP address and MAC address of the source network router (i.e., UPF 30A), and the IP address of terminal 20B as the context of the UL route between source UPF 30A and source base station 10. The first request message also includes a PDU session identifier.

[0122] The second request message requests settings related to the context and ingress blocking of the DL path between the source UPF 30A and the source base station 10. The second request message also includes a PDU session identifier. The second request message also includes a request for the IP address and MAC address of the destination router (i.e., UPF 30A3).

[0123] S306: UPF 30A3 starts an operation based on the context of source UPF 30A2.

[0124] S307: The UPF 30A3 transmits a first response message and a second response message to the inter-satellite cooperation NF 30R in response to the first request message and the second request message received in S305. The second response message includes the IP address and the MAC address of the destination router (i.e., the UPF 30A3).

[0125] S308: The inter-satellite cooperation NF 30R transmits three request messages (PFCP Session Modification requests) for modifying the user data transfer path to the UPF 30A3.

[0126] The first request message requests unblocking of the entrance for DL ​​user data and includes a PDU session identifier corresponding to the user data.

[0127] The second request message requests release of buffering for UL user data and includes a PDU session identifier corresponding to the user data.

[0128] The third request message requests release of buffering for DL ​​user data and includes a PDU session identifier corresponding to the user data.

[0129] S309: The UPF 30A3 transmits, to the inter-satellite link NF 30R, first to third response messages in response to the first to third request messages received in S308, respectively.

[0130] S310: The inter-satellite link NF 30R determines the inter-satellite link NF 30P of the source network, which is the destination to transmit the Path switch request, based on the IP address and MAC address of the router (that is, the UPF 30A) of the source network.

[0131] S311: The inter-satellite cooperation NF 30R transmits a request message (Path Switch request) for path switching to the inter-satellite cooperation NF 30P of the source network. The request message includes a PDU session identifier and requests that the path associated with the IP address of the terminal 20B, which corresponds to the identifier, be switched from a router of the source destination network (i.e., UPF 30A2) to a router of the destination destination network (i.e., UPF 30A3). That is, the request message requests switching from the first routing information [destination address = IP address of the terminal 20B, MAC address and IP address of the router (UPF 30A2)] to the second routing information [destination address = IP address of the terminal 20B, MAC address and IP address of the router (UPF 30A3)].

[0132] S312: The inter-satellite communication NF 30P transmits a request message (PFCP Session Modification request) for modifying the user data transfer path to the UPF 30A. The request message includes a PDU session identifier and requests that the path associated with the IP address of the terminal 20B, which corresponds to the identifier, be switched from a router in the source destination network (i.e., UPF 30A2) to a router in the destination destination network (i.e., UPF 30A3).

[0133] S313: UPF 30A changes the settings of the context and the N6 interface exit stored in its own device. That is, UPF 30A switches the route associated with the IP address of terminal 20B from the router of the source destination network (i.e., UPF 30A2) to the router of the destination destination network (i.e., UPF 30A3).

[0134] S314: The UPF 30A transmits a response message (PFCP Session Modification response) to the request message received in S312 to the inter-satellite link NF 30P.

[0135] S315: UPF 30A transfers the audio media sent from terminal 20A to UPF 30A3, which then transfers it to terminal 20B. Here, UPF 30A may transfer the audio media to UPF 30A3 using the MAC address of UPF 30A3, which corresponds to a router in the destination network, or may transfer the audio media using the IP address of UPF 30A3 after encapsulating it using IPSec or the like.

[0136] S316: UPF 30A3 transfers the audio media sent from terminal 20B to UPF 30A, and UPF 30A further transfers it to terminal 20A. Here, UPF 30A3 may transfer the audio media to UPF 30A using the MAC address of UPF 30A, which corresponds to a router in the source network, or may encapsulate the audio media using IPSec or the like and then use the IP address of UPF 30A.

[0137] According to the above-described embodiment, in a wireless communication system, the address of the user plane function can be appropriately switched when switching between satellites.

[0138] (Device Configuration) Next, a description will be given of an example of the functional configuration of the base station 10, network node 30, and terminal 20 that perform the processes and operations described above. The base station 10, network node 30, and terminal 20 include functions for performing the above-described embodiments. However, the base station 10, network node 30, and terminal 20 may each include only a part of the functions of the embodiments.

[0139] <Base Station 10 and Network Node 30> Fig. 8 is a diagram showing an example of the functional configuration of the base station 10 and the network node 30. As shown in Fig. 8, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Fig. 8 is merely an example. As long as the operations according to the embodiment of the present invention can be performed, the names of the functional divisions and functional units may be any. Note that the network node 30 may have the same functional configuration as the base station 10. Furthermore, a network node 30 having multiple different functions in the system architecture may be composed of multiple network nodes 30 separated by function.

[0140] The transmitter 110 includes a function of generating a signal to be transmitted to the terminal 20 or another network node 30 and transmitting the signal by wire or wirelessly. The receiver 120 includes a function of receiving various signals transmitted from the terminal 20 or another network node 30 and acquiring, for example, information of a higher layer from the received signal. A communication unit including the transmitter 110 and the receiver 120 may be configured.

[0141] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20 in a storage device, and reads out the information from the storage device as needed.

[0142] The control unit 140 performs the processes described in the embodiments, etc. The control unit 140 also performs processes related to communication with the terminal 20. The function unit related to signal transmission in the control unit 140 may be included in the transmitting unit 110, and the function unit related to signal reception in the control unit 140 may be included in the receiving unit 120.

[0143] <Terminal 20> Fig. 9 is a diagram showing an example of the functional configuration of the terminal 20. As shown in Fig. 9, the terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Fig. 9 is merely an example. As long as the operations related to the embodiment of the present invention can be performed, the names of the functional divisions and functional units may be any. In addition, the communication device that becomes the resource holder 20 may have the same functional configuration as the terminal 20.

[0144] The transmitter 210 creates a transmission signal from transmission data and transmits the transmission signal wirelessly. The receiver 220 receives various signals wirelessly and acquires higher layer signals from the received physical layer signals. The receiver 220 also has a function of receiving control signals, reference signals, etc. transmitted from the network node 30. A communication unit including the transmitter 210 and the receiver 220 may be configured.

[0145] The setting unit 230 stores various pieces of setting information received from the network node 30 by the receiving unit 220 in a storage device, and reads them out from the storage device as needed. The setting unit 230 also stores setting information that is set in advance.

[0146] The control unit 240 performs the processes described in the embodiments. The function unit related to signal transmission in the control unit 240 may be included in the transmitting unit 210, and the function unit related to signal reception in the control unit 240 may be included in the receiving unit 220.

[0147] (Hardware Configuration) The block diagrams (FIGS. 8 and 9) used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining software with the single device or the multiple devices.

[0148] Functions include, but are not limited to, judgment, determination, assessment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0149] For example, the base station 10, the network node 30, the terminal 20, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 10 is a diagram illustrating an example of the hardware configuration of the base station 10 and the terminal 20 according to an embodiment of the present disclosure. The network node 30 may have the same hardware configuration as the base station 10. The above-described base station 10 and the terminal 20 may be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0150] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the base station 10 and the terminal 20 may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0151] Each function in the base station 10 and the terminal 20 is realized by loading specified software (programs) onto hardware such as the processor 1001, the memory device 1002, etc., so that the processor 1001 performs calculations, controls communication by the communication device 1004, and controls at least one of reading and writing data in the memory device 1002 and the auxiliary memory device 1003.

[0152] The processor 1001 controls the entire computer by running, for example, an operating system. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, the above-mentioned control unit 140, control unit 240, etc. may be realized by the processor 1001.

[0153] The processor 1001 also reads programs (program codes), software modules, data, etc. from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002 and executes various processes in accordance with the programs. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 140 of the base station 10 shown in FIG. 8 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. For example, the control unit 240 of the terminal 20 shown in FIG. 9 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. While the above-described various processes have been described as being executed by one processor 1001, they may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may also be transmitted from a network via a telecommunications line.

[0154] The storage device 1002 is a computer-readable recording medium and may be configured, for example, by at least one of a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), etc. The storage device 1002 may also be called a register, a cache, a main memory, etc. The storage device 1002 can store executable programs (program codes), software modules, etc. for implementing a communication method according to an embodiment of the present disclosure.

[0155] The secondary storage device 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. The above-mentioned storage medium may be, for example, a database, a server, or other appropriate medium including at least one of the storage device 1002 and the secondary storage device 1003.

[0156] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, a transmission / reception antenna, an amplifier unit, a transmission / reception unit, a transmission path interface, etc. may be realized by the communication device 1004. The transmission / reception unit may be implemented as a transmission unit and a reception unit that are physically or logically separated.

[0157] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0158] Furthermore, each device such as the processor 1001 and the storage device 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0159] Furthermore, the base station 10 and the terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0160] Fig. 11 shows an example configuration of a vehicle 2001. As shown in Fig. 11, the vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect / embodiment described in the present disclosure may be applied to a communication device mounted on the vehicle 2001, and may be applied to the communication module 2013, for example.

[0161] The drive unit 2002 is configured, for example, by an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel operated by the user.

[0162] The electronic control unit 2010 is composed of a microprocessor 2031, a memory (ROM, RAM) 2032, and a communication port (IO port) 2033. Signals are input to the electronic control unit 2010 from various sensors 2021 to 2029 provided in the vehicle 2001. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0163] The signals from the various sensors 2021 to 2029 include a current signal from a current sensor 2021 that senses the current of the motor, a rotation speed signal of the front and rear wheels obtained by a rotation speed sensor 2022, an air pressure signal of the front and rear wheels obtained by an air pressure sensor 2023, a vehicle speed signal obtained by a vehicle speed sensor 2024, an acceleration signal obtained by an acceleration sensor 2025, an accelerator pedal depression amount signal obtained by an accelerator pedal sensor 2029, a brake pedal depression amount signal obtained by a brake pedal sensor 2026, a shift lever operation signal obtained by a shift lever sensor 2027, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 2028.

[0164] The information service unit 2012 is composed of various devices, such as a car navigation system, an audio system, speakers, a television, and a radio, for providing (outputting) various types of information, such as driving information, traffic information, and entertainment information, and one or more ECUs for controlling these devices. The information service unit 2012 uses information acquired from external devices via the communication module 2013 or the like to provide various types of multimedia information and multimedia services to the occupants of the vehicle 2001. The information service unit 2012 may include input devices (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, a touch panel, etc.) that accept input from the outside, and may also include output devices (e.g., a display, a speaker, an LED lamp, a touch panel, etc.) that output information to the outside.

[0165] The driving assistance system unit 2030 is composed of various devices that provide functions for preventing accidents and reducing the driving burden on the driver, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS, etc.), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps, etc.), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System), etc.), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. In addition, the driving assistance system unit 2030 transmits and receives various information via the communication module 2013 to realize the driving assistance function or the autonomous driving function.

[0166] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via the communication port. For example, the communication module 2013 transmits and receives data via the communication port 2033 to and from the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021 to 29, which are provided in the vehicle 2001.

[0167] The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, or the like.

[0168] The communication module 2013 may transmit at least one of signals from the above-mentioned various sensors 2021-2028 input to the electronic control unit 2010, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 2012 to an external device via wireless communication. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include information based on the above-mentioned input.

[0169] The communication module 2013 receives various information (traffic information, traffic signal information, vehicle-to-vehicle information, etc.) transmitted from external devices and displays it on an information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH (or data / information decoded from the PDSCH) received by the communication module 2013). The communication module 2013 also stores the various information received from external devices in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021 to 2029, etc. provided in the vehicle 2001.

[0170] <Additional Notes> (Additional Note 1) A network node having: a receiving unit that receives a first message including routing information, including an IP (Internet Protocol) address of an opposite terminal and a physical address and IP address of a router, from a first network node at a source of movement that processes user data; and a transmitting unit that transmits a second message including the routing information to a second network node at a destination of movement that processes the user data. (Supplementary Item 2) A network node having: a receiving unit that receives a first message transmitted from a first network node at a source of movement that processes user data, the first message including an IP (Internet Protocol) address of an accommodating terminal, the physical address and IP address of the first network node, and the physical address and IP address of a second network node that processes user data to be routed to an opposing terminal; and a receiving unit that receives a second message from a third network node at a destination of movement that processes user data, the second message including the physical address and IP address of the third network node; a control unit that identifies a fourth network node based on the physical address and IP address of the second network node; and a transmitting unit that transmits to the fourth network node a third message including a request to switch to first routing information that sends IP packets having the IP address of the accommodating terminal as their destination to the physical address and IP address of the first network node, and second routing information that sends IP packets having the IP address of the accommodating terminal as their destination to the physical address and IP address of the third network node. (Supplementary clause 3) A network node having: a receiving unit that receives from a terminal a first message indicating that voice communication is being set up, the message including an IP (Internet Protocol) address of the terminal; and a second message that receives from a first network node a second message including an identifier of a second network node that routes media for the voice communication to the terminal; and a transmitting unit that transmits to the second network node a third message indicating that voice communication is being set up, the third message including the IP address of the terminal and an identifier of the second network node.(Supplementary Item 4) A network node comprising: a receiving unit that receives from a first network node a first message including an IP (Internet Protocol) address of a terminal and an identifier of a second network node that routes voice communication media to the terminal, a control unit that specifies a physical address and an IP address of the second network node from the identifier, and a transmitting unit that transmits to a third network node a second message including routing information including the IP address of the terminal and the physical address and IP address of the second network node. (Supplementary Item 5) A network node that is deployed on a satellite and has a routing function, comprising: a receiving unit that receives from a first network node that is deployed between the network node itself and a network node that manages a user data session a message requesting establishment of a user data transfer path, the message including a session identifier and an IP (Internet Protocol) address of a terminal accommodated by the network node itself, and a control unit that stores the session identifier and the IP address. (Supplementary Item 6) A communication method executed by a network node, comprising: a step of receiving a first message including routing information including an IP (Internet Protocol) address of an opposite terminal and a physical address and IP address of a router from a first network node at a source of movement that processes user data; and a step of transmitting a second message including the routing information to a second network node at a destination of movement that processes the user data.

[0171] Any of Supplementary Items 1 to 6 makes it possible to appropriately switch the address of the user plane function when switching satellites in a wireless communication system.

[0172] (Supplementary Notes on the Embodiments) Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, and substitutions. While specific numerical examples have been used to facilitate understanding of the invention, unless otherwise specified, these numerical values ​​are merely examples, and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention; matters described in two or more items may be used in combination as needed, and matters described in one item may apply to matters described in another item (as long as there is no contradiction). Boundaries between functional units or processing units in functional block diagrams do not necessarily correspond to boundaries between physical components. The operations of multiple functional units may be performed by a single physical component, or the operations of a single functional unit may be performed by multiple physical components. The order of processing steps described in the embodiments may be reversed as long as there is no contradiction. For convenience of processing description, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be realized by hardware, software, or a combination thereof. The software operated by the processor of the base station 10 in accordance with an embodiment of the present invention and the software operated by the processor of the terminal 20 in accordance with an embodiment of the present invention may each be stored in random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

[0173] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling), broadcast information (Master Information Block (MIB), System Information Block (SIB)), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0174] Each aspect / embodiment described in the present disclosure may be implemented using any of the following standards: LTE (Long Term Evolution), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (x is, for example, an integer or a decimal number)), FRA (Future Radio Access), NR (new Radio), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 (WiMAX (registered trademark)), IEEE 802.30 (WiMAX (registered trademark)), IEEE 802.31 (Wi-Fi (registered trademark)), IEEE 802.32 (WiMAX (registered trademark)), IEEE 802.33 (WiMAX (registered trademark)), IEEE 802.34 ( The present invention may be applied to at least one of systems using 802.20, UWB (Ultra-Wide Band), Bluetooth (registered trademark), or other suitable systems, and next-generation systems that are extended, modified, created, or defined based on these systems. The present invention may also be applied to a combination of multiple systems (e.g., a combination of LTE and / or LTE-A with 5G).

[0175] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described herein may be rearranged unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order and are not limited to the particular order presented.

[0176] In this specification, a specific operation described as being performed by the base station 10 may be performed by its upper node in some cases. In a network consisting of one or more network nodes having the base station 10, it is clear that various operations performed for communication with the terminal 20 may be performed by at least one of the base station 10 and another network node other than the base station 10 (such as, but not limited to, an MME or an S-GW). Although the above example illustrates a case where there is one other network node other than the base station 10, the other network node may be a combination of multiple other network nodes (such as an MME and an S-GW).

[0177] The information, signals, etc. described in the present disclosure may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0178] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be transmitted to another device.

[0179] In the present disclosure, the determination may be made by a value represented by one bit (0 or 1), by a Boolean value (true or false), or by a comparison of numerical values ​​(e.g., comparison with a predetermined value).

[0180] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0181] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0182] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0183] Note that terms described in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0184] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0185] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0186] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

[0187] In the present disclosure, terms such as "base station (BS)," "radio base station," "base station device," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. A base station may also be referred to by terms such as a macrocell, a small cell, a femtocell, and a picocell.

[0188] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the overall coverage area of ​​the base station can be partitioned into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a small indoor base station (RRH: Remote Radio Head)). The terms "cell" or "sector" refer to part or all of the coverage area of ​​a base station and / or base station subsystem that provides communication services within that coverage.

[0189] In the present disclosure, the base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control or operate based on the information.

[0190] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," and the like may be used interchangeably.

[0191] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0192] At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a mobile object, the mobile object itself, etc. The mobile object refers to a movable object, and may move at any speed. Naturally, this also includes cases where the mobile object is stationary. Examples of the mobile object include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcars, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and objects mounted thereon. The mobile object may also be a mobile object that moves autonomously based on an operational command. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may be a device that does not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0193] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple terminals 20 (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0194] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station may be configured to have the functions of the user terminal described above.

[0195] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0196] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0197] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0198] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0199] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0200] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0201] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0202] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0203] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0204] The aspects / embodiments described in this disclosure may be used alone, in combination, or switched depending on the implementation. Notification of predetermined information (e.g., notification that "X is true") is not limited to explicit notification, but may be implicit (e.g., not notifying the predetermined information).

[0205] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0206] 10 Base station 110 Transmitter 120 Receiver 130 Setting unit 140 Control unit 20 Terminal 210 Transmitter 220 Receiver 230 Setting unit 240 Control unit 30 Network node 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Front wheels 2008 Rear wheels 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 RPM sensor 2023 Tire pressure sensor 2024 Vehicle speed sensor 2025 Acceleration sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030 Driving assistance system unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port (IO port)

Claims

1. A network node having: a receiving unit that receives a first message including routing information, including an IP (Internet Protocol) address of an opposite terminal and a physical address and IP address of a router, from a first network node at a source of movement that processes user data; and a transmitting unit that transmits a second message including the routing information to a second network node at a destination of movement that processes the user data.

2. A network node having: a receiving unit that receives a first message transmitted from a first network node at the source of a move that processes user data, the first message including the IP (Internet Protocol) address of the accommodating terminal, the physical address and IP address of the first network node, and the physical address and IP address of a second network node that processes user data and routes it to an opposing terminal; and a second message that receives from a third network node at the destination of the move that processes the user data, the second message including the physical address and IP address of the third network node; a control unit that identifies a fourth network node based on the physical address and IP address of the second network node; and a transmitting unit that transmits to the fourth network node a third message including a request to switch to first routing information that sends IP packets having the IP address of the accommodating terminal as their destination to the physical address and IP address of the first network node, and second routing information that sends IP packets having the IP address of the accommodating terminal as their destination to the physical address and IP address of the third network node.

3. A network node having: a receiving unit that receives from a terminal a first message indicating that voice communication is being set up, the message including the IP (Internet Protocol) address of the terminal; and a second message that receives from a first network node a second message including an identifier of a second network node that routes media for the voice communication to the terminal; and a transmitting unit that transmits to the second network node a third message indicating that voice communication is being set up, the third message including the IP address of the terminal and the identifier of the second network node.

4. A network node having: a receiving unit that receives from a first network node a first message including an IP (Internet Protocol) address of a terminal and an identifier of a second network node that routes voice communication media to the terminal; a control unit that identifies the physical address and IP address of the second network node from the identifier; and a transmitting unit that transmits to a third network node a second message including routing information including the IP address of the terminal and the physical address and IP address of the second network node.

5. A network node with routing functionality that is deployed on a satellite, comprising: a receiving unit that receives a message requesting the establishment of a user data transfer path, the message including a session identifier and an IP (Internet Protocol) address of a terminal accommodated by the device, from a first network node that is deployed between the device and a network node that manages a user data session; and a control unit that stores the session identifier and the IP address.

6. A communication method executed by a network node, comprising: a step of receiving a first message including routing information, including an IP (Internet Protocol) address of an opposite terminal and a physical address and IP address of a router, from a first network node at a source of movement that processes user data; and a step of sending a second message including the routing information to a second network node at a destination of movement that processes the user data.

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