Network node, terminal, and communication method

Abstract

This network node includes: a reception unit that receives, from a terminal, a first message requesting a call for media communication; a control unit that uses the first message as a basis to generate first setting information used in a second message requesting a call for media communication corresponding to a protocol used on the called side; and a transmission unit that transmits the second message including the first setting information to a second network node. The reception unit receives a third message that responds to the second message from the second network node. The control unit uses the third message as a basis to generate second setting information corresponding to a protocol used on the calling side and used in a fourth message that responds to the first message. The transmission unit transmits the fourth message including the second setting information to the terminal.

Description

Network Node, Terminal, and Communication Method

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

[0002] In 3GPP (Registered Trademark) (3rd Generation Partnership Project), in order to achieve further increase in system capacity, further increase in data transmission speed, further reduction in latency in the radio section, etc., a radio communication method called 5G or NR (New Radio) (hereinafter, this radio communication method is referred to as "5G" or "NR") is being studied. In 5G, various radio technologies are being studied in order to meet the requirement of achieving a throughput of 10 Gbps or more and reducing the latency in the radio section to 1 ms or less.

[0003] Also, the network architectures in 5GC (5G Core Network) or 5GS (5G System), which is the core network in 5G, and 6GC (6G Core Network) or 6GS (6G System), which is the successor of 5G, are also being studied (for example, Non-Patent Document 1).

[0004] Also, the IMS (IP Multimedia Subsystem) architecture for realizing services such as voice calls is also being studied (for example, Non-Patent Documents 2-3). In an IMS voice call, after the terminal registers with the IMS, when making a voice call, it uses network nodes (P-CSCF, S-CSCF, I-CSCF, HSS, etc.) inside the IMS to connect to the destination terminal.

[0005] 3GPP TS 23.501 V18.7.0 (2024-09) 3GPP TS 23.228 V18.7.0 (2024-09) 3GPP TS 26.114 V18.8.0 (2024-09) 3GPP TS 23.502 V18.7.0 (2024-09)

[0006] In 4G and 5G, voice and video call services utilize a fallback mechanism during generational transitions. While voice and video call services are expected to be used in 6G as well, the market trend of decreasing total voice and video call traffic (particularly the number of calls) in recent years necessitates a mechanism that reduces system load during generational transitions.

[0007] The present invention has been made in view of the above points, and aims to provide a mechanism for reducing the system load in a voice / video communication system in a wireless communication network.

[0008] According to the disclosed technology, a network node is provided which includes: a receiving unit that receives a first message requesting a media communication call from a terminal; a control unit that generates first configuration information to be used in a second message requesting a media communication call according to the protocol used on the receiving side, based on the first message; and a transmitting unit that transmits the second message including the first configuration information to a second network node on the receiving side. The receiving unit receives a third message in response to the second message from the second network node, the control unit generates second configuration information to be used in a fourth message in response to the first message according to the protocol used on the sending side, based on the third message, and the transmitting unit transmits the fourth message including the second configuration information to the terminal.

[0009] According to the disclosed technology, a mechanism can be provided to reduce the system load in voice / video communication systems in wireless communication networks.

[0010] This is a diagram illustrating an example of a communication system. This is a diagram illustrating an example of a communication system in a roaming environment. This is a diagram illustrating an example of an IMS network. This is a diagram illustrating an example of a communication system including an IMS emulator in an embodiment of the present invention. This is a diagram showing an example of a sequence diagram in an embodiment of the present invention. This 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. This is a diagram showing an example of the functional configuration of a terminal 20 in an embodiment of the present invention. This 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. This is a diagram showing an example of the configuration of a vehicle 2001 in an embodiment of the present invention.

[0011] Embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are examples, and the embodiments to which the present invention applies are not limited to those described below. Furthermore, in the following description, " / " means "and / or" unless otherwise specified, or unless it is clear from the context that it has a different meaning.

[0012] In the operation of the wireless communication system according to the embodiments of the present invention, existing technologies may be used as appropriate. However, such existing technologies include, for example, existing LTE, but are not limited to existing LTE. Furthermore, the term "LTE" as used herein has a broad meaning that includes LTE-Advanced, LTE-Advanced and later technologies (e.g., NR), or wireless LAN (Local Area Network), unless otherwise specified.

[0013] Furthermore, in the embodiments of the present invention, "configuring" wireless parameters means that predetermined values ​​are pre-configured, or that wireless parameters notified from the network node 30 or terminal 20 are configured.

[0014] Figure 1 is a diagram illustrating an example of a communication system. As shown in Figure 1, the communication system consists of a terminal 20 (UE) and multiple network nodes 30. Hereafter, one network node 30 will be assumed to correspond to each function, but one network node 30 may implement multiple functions, or multiple network nodes 30 may implement one function. Also, the "connection" described below may be a logical connection or a physical connection.

[0015] The RAN (Radio Access Network) is a network node 30 having wireless access functionality, which may include a base station 10, and is connected to a UE, AMF (Access and Mobility Management Function), and 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), registration management, connection management, reachability management, and terminal mobility management. The UPF is a network node 30 interconnected with the DN (Data Network) and having functions related to processing user plane data, such as a PDU (Protocol Data Unit) session point to the outside, packet routing and forwarding, and user plane QoS (Quality of Service) handling. The UPF and DN constitute a network slice. In the wireless communication network in the embodiment of the present invention, a plurality of network slices are constructed.

[0016] AMF is connected to 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). AMF, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, and AF are network nodes 30 that are interconnected via interfaces based on their respective services: Namf, Nsmf, Nnssf, Nnef, Nnrf, Nudm, Nausf, Npcf, and Naf.

[0017] The SMF is a network node 30 that has functions such as session management, IP (Internet Protocol) address allocation and management for UEs, DHCP (Dynamic Host Configuration Protocol) functionality, ARP (Address Resolution Protocol) proxy, and roaming functionality. The NEF is a network node 30 that has the function of notifying other NFs (Network Functions) of capabilities and events. The NSSF is a network node 30 that has functions such as selecting the network slice to which the UE connects, determining the allowed NSSAI (Network Slice Selection Assistance Information), determining the NSSAI to be set, and determining the AMF set to which the UE connects. The PCF is a network node 30 that has the function of controlling network policies. The AF is a network node 30 that has the function of controlling application servers. The NRF is a network node 30 that has the 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 the UDR (User Data Repository) that holds the said data.

[0018] Figure 2 is a diagram illustrating an example of a communication system in a roaming environment. As shown in Figure 2, the network consists of a terminal 20 (UE) and multiple network nodes 30. Hereafter, one network node 30 will be assigned to each function, but one network node 30 may implement multiple functions, or multiple network nodes 30 may implement one function. Also, the "connection" described below may be a logical connection or a physical connection.

[0019] The RAN is a network node 30 having wireless access functionality and is connected to the UE, AMF, and 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 interconnected with the DN, having functions such as external PDU session point, packet routing and forwarding, and user plane QoS handling. The UPF and DN constitute a network slice. In the wireless communication network according to the embodiment of the present invention, multiple network slices are constructed.

[0020] AMF is connected to UE, RAN, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, AF, and SEPP (Security Edge Protection Proxy). AMF, SMF, NSSF, NEF, NRF, UDM, AUSF, PCF, and AF are network nodes 30 that are interconnected via interfaces based on their respective services: Namf, Nsmf, Nnssf, Nnef, Nnrf, Nudm, Nausf, Npcf, and Naf.

[0021] SMF is a network node 30 that has functions such as session management, IP address allocation and management for UEs, DHCP functionality, ARP proxy, and roaming functionality. NEF is a network node 30 that has the function of notifying other NFs of capabilities and events. NSSF is a network node 30 that has functions such as selecting the network slice to which the UE connects, determining which NSSAIs are allowed, determining which NSSAIs are configured, and determining which AMF set the UE connects to. PCF is a network node 30 that has the function of controlling network policies. AF is a network node 30 that has the function of controlling application servers. NRF is a network node 30 that has the function of discovering NF instances that provide services. SEPP is an opaque proxy that filters control plane messages between PLMNs (Public Land Mobile Networks). In Figure 2, vSEPP is the SEPP in the visited network, and hSEPP is the SEPP in the home network.

[0022] As shown in Figure 2, the UE is in a roaming environment connected to the RAN and AMF in the Visited PLMN. The Visited PLMN and Home PLMN are connected via vSEPP and hSEPP. The UE can communicate with the UDM of the Home PLMN, for example, via the AMF of the Visited PLMN.

[0023] Figure 3 is a diagram illustrating an example of an IMS network. As shown in Figure 3, the IMS network consists of a terminal 20 (UE) and multiple network nodes 30 in both the originating network and the terminating network. Hereafter, one network node 30 will be assumed to correspond to each function, but one network node 30 may implement multiple functions, or multiple network nodes 30 may implement one function. Also, the "connection" described below may be a logical connection or a physical connection. The network node 30 has the following functions, for example, as described in Non-Patent Document 2.

[0024] The IMS-AGW (Access Gateway) is a network node 30 that has the functions of a gateway between the UE and the IMS network, as well as functions related to voice communication access processing.

[0025] P-CSCF (Proxy-Call Session Control Function) is a network node 30 that has proxy functions between the UE and the IMS network, as well as access control functions for voice communications.

[0026] S-CSCF (Serving-Call Session Control Function) is a network node 30 that has functions related to session control for the UE.

[0027] The I-CSCF (Interrogate-Call Session Control Function) is a connection point on the receiving side between networks in the IMS network (for example, the sending side and the receiving side), and is a network node 30 that has functions such as forwarding received SIP requests to its own network's S-CSCF.

[0028] The IMS AS (IP Multimedia Subsystem Application Server) is a network node 30 in the IMS network that has functions such as communicating with the DCSF for event notification and receiving data channel control instructions from the DCSF and communicating with the MF. The IMS AS also receives a registration request for the communication termination point from the DCSF (Data Channel Signalling Function), converts the received registration request into a SIP Register, and sends it to the S-CSCF (Serving-Call Session Control Function). Furthermore, the IMS AS converts a data channel establishment request received from the DCSF into a SIP INVITE and sends it to the S-CSCF.

[0029] The DCSF (Data Channel Signaling Function) is a network node 30 that has functions such as receiving event reports from IMS-AS and deciding whether or not to allow the provision of data channel services, managing bootstrap data channels, and HTTP web server functionality.

[0030] The Media Function (MF) is a network node 30 in the IMS network that has functions such as media resource management and data channel media traffic forwarding. The MF also processes media between the Data Channel Application Server (DCAS), which is the communication termination point, and the destination termination point based on the configuration information received from the Data Channel Application Server (DCSF). The MF may also be called the Data Channel Media Function (DCMF). The MF may also be called the Multimedia Resource Function (MRF).

[0031] DCAS (Data Channel Application Server) is a network node 30 that has functions such as being a communication termination point for media and signaling in the IMS network.

[0032] Furthermore, the IMS network may be equipped with an E-CSCF (Emergency Call Session Control Function) for handling emergency calls, and an IBCF (Interconnection Border Control Function) for handling SIP-related processing in interconnections between different domains.

[0033] (Example) This section describes a mechanism for reducing the system load in a voice / video communication system in a wireless communication network. In this example, voice / video calls are established using an IMS emulator (including a virtual terminal) via the user plane between the terminal and the core network. Furthermore, by introducing a virtual terminal within the IMS emulator, it is possible to reduce the processing load on the terminal side and reduce the number of signals. Here, voice / video communication (calls) may also be called media communication (calls), and may include communication such as text / still images.

[0034] Figure 4 is a diagram illustrating an example of a communication system including an IMS emulator in an embodiment of the present invention. As shown in Figure 4, a terminal communicates with the IMS emulator via a voice PDU session established on the user plane. The IMS emulator has the functions of a virtual terminal and a virtual IMS, supporting IMS voice / video communication based on the SIP protocol, and as one of the network nodes having an Application Function (AF), it can communicate with network nodes such as PCF and HSS in the core network via the functions of the virtual IMS. Here, the functions of the virtual IMS include, for example, the functions of existing IMS network nodes such as S-CSCF, P-CSCF, I-CSCF, E-CSCF, and IBCF. Alternatively, existing IMS network nodes may be used as all or part of the functions of the virtual IMS, and the IMS emulator may include only a virtual terminal.

[0035] Furthermore, in Figure 4, after the PDU session, the terminal sends a message to the IMS emulator requesting a call connection, which contains information equivalent to an SDP (Session Description Protocol) containing the information necessary for SIP-based IMS voice / video call connection. The virtual terminal in the IMS emulator generates SDP information for SIP-based IMS voice / video call connection based on the received information. In addition, within the IMS emulator, the virtual terminal sends the generated SDP information to the virtual IMS. The virtual IMS within the IMS emulator establishes IMS voice / video communication in cooperation with other network nodes in the core network (PCF, HSS, etc.) and other IMSs at the receiving terminal, according to the processing for SIP-based IMS voice / video call connection.

[0036] Next, the details of the processing in this embodiment will be explained using a sequence diagram. Figure 5 is a diagram showing an example of a sequence diagram in an embodiment of the present invention. In this sequence, a procedure for connecting a voice / video call from terminal 20A located in the first network (PLMN) to terminal 20C located in the second network (PLMN) is executed. The processing of each step will be explained below.

[0037] S100: A PDU session for voice is established on the user plane between the IMS terminal 20A and the IMS emulator 30C. For details of the procedure for establishing the PDU session, see, for example, section 4.3.2 of Non-Patent Document 4.

[0038] S101: IMS terminal 20A accepts input from the user for the telephone number of the receiving IMS terminal 20C. This input may include a URI (Uniform Resource Identifier) ​​such as the hostname of the SIP server, in addition to the telephone number.

[0039] S102: The IMS terminal 20A sends a message to the IMS emulator 30C, requesting a voice / video call using the PDU session on the user plane established in S100. The message may include the phone number / URI input in S101, conditions (Precondition) such as service quality (QoS) related to the call, and information related to the codec.

[0040] S103: The virtual terminal 20B in the IMS emulator 30C generates SDP information including the configuration information required for establishing an SIP-based IMS voice / video call connection based on the information (phone number / URI, call-related conditions, and codec-related information, etc.) contained in the message received in S102.

[0041] S104: In the IMS emulator 30C, the virtual terminal 20B sends a message (SIP INVITE) requesting an SIP-based IMS voice / video call to the virtual IMS 30B.

[0042] Hereinafter, from S105 to S120, the processes related to establishing an SIP-based IMS voice / video call connection in the existing specification are executed.

[0043] S105: The virtual IMS 30B executes the processes required for establishing an SIP-based IMS voice / video call connection based on the message received in S104.

[0044] S106: The virtual IMS 30B in the IMS emulator 30C sends the message (SIP INVITE) received in S105 to another IMS 40, which is the IMS in the second PLMN on the receiving side.

[0045] S107: The other IMS 40 sends the message (SIP INVITE) received in S106 to the IMS terminal 20C.

[0046] S108: The IMS terminal 20C sends a message (183 session progress) indicating the continuation of the session as a response to the message (SIP INVITE) received in S107 to the other IMS 40.

[0047] S109: Another IMS40 transmits the message (183 session progress) received in S108 to the virtual IMS30B of the IMS emulator 30C.

[0048] S110: Inside the IMS emulator 30C, the virtual IMS30B transmits the message (183 session progress) received in S109 to the virtual terminal 20B.

[0049] S111: Between the IMS emulator 30C, another IMS40, and the IMS terminal 20C, processing regarding notification of the codec used in IMS voice / video communication based on the existing specifications is executed.

[0050] S112: Between the IMS emulator 30C, another IMS40, and the IMS terminal 20C, processing regarding confirmation of bearer setting in IMS voice / video communication based on the existing specifications is executed.

[0051] S113: Between the IMS emulator 30C, another IMS40, and the IMS terminal 20C, processing regarding incoming call of the terminating terminal in IMS voice / video communication based on the existing specifications is executed.

[0052] S114: The IMS terminal 20C executes session acceptance, such as by accepting the user pressing the call button for the call in IMS voice / video communication.

[0053] S115: The IMS terminal 20C transmits a message (200 OK) indicating session acceptance to another IMS40.

[0054] S116: Another IMS40 transmits the message (200 OK) received in S115 to the virtual IMS30B of the IMS emulator 30C.

[0055] S117: Inside the IMS emulator 30C, the virtual IMS30B transmits the message (200 OK) received in S116 to the virtual terminal 20B.

[0056] S118: Within the IMS emulator 30C, the virtual terminal 20B sends an acknowledgment (ACK) to the virtual IMS 30B for the message (200 OK) received in S117.

[0057] S119: The virtual IMS30B within the IMS emulator 30C sends an acknowledgment (ACK) to the other IMS40 for the message (200 OK) received in S118.

[0058] S120: The other IMS40 sends an acknowledgment (ACK) to the IMS terminal 20C for the message (200 OK) received in S119.

[0059] S121: Based on the results of processing S103 to S117, the IMS terminal 20B in the IMS emulator 30C generates the configuration information necessary to respond to the voice / video call received in S102.

[0060] S122: The IMS terminal 20B in the IMS emulator 30C sends a message to the IMS terminal 20A that includes the configuration information generated in S122 and responds to the voice / video call received in S102. This message may include information similar to that included in the message responding to a call in an IMS voice / video call based on SIP, such as the media type, codec information, and SDP information.

[0061] S123: A voice / video / other media call is made between IMS terminal 20A located in the first PLMN and IMS terminal 20C located in the second PLMN.

[0062] (Modifications) Modifications will now be explained. In the sequence diagram of Figure 5, the IMS terminal 20A may be a new generation (e.g., 6G) terminal that does not support SIP-based IMS voice / video calls. Also, the signals between the terminal (IMS terminal 20A) and the IMS emulator 30C may not be limited to PDU sessions on the 5G user plane, but may be signals on the new generation user plane. Furthermore, the IMS emulator 30C may be a network node that emulates (protocol conversion) older generation media communication. In addition, the IMS emulator may perform message generation / protocol conversion that corresponds to the generation (5G, etc.) / protocol (SIP, etc.) supported by the receiving network.

[0063] (Effects) In the above embodiment, by introducing a virtual terminal within the IMS emulator, it is possible to reduce the processing load related to voice connections on the terminal side and reduce the number of signals between the terminal and the core network, thereby reducing the load on the entire wireless communication system. Furthermore, in an AF with an IMS emulator, it is possible to terminate SIP-based signaling.

[0064] In other words, the above-described embodiment provides a mechanism for reducing the system load in a voice / video communication system in a wireless communication network.

[0065] (Device Configuration) Next, an example of the functional configuration of the base station 10, network node 30, and terminal 20 that perform the processing and operations described above will be explained. The base station 10, network node 30, and terminal 20 include the functions to perform the embodiments described above. However, the base station 10, network node 30, and terminal 20 may each be equipped with only some of the functions in the embodiments.

[0066] <Base Station 10 and Network Node 30> Figure 6 shows an example of the functional configuration of a base station 10 and a network node 30. As shown in Figure 6, 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 Figure 6 is merely an example. The functional classifications and names of the functional units can be anything as long as they can perform the operations according to the embodiment of the present invention. The network node 30 may have the same functional configuration as the base station 10. Furthermore, a network node 30 having multiple different functions on the system architecture may be composed of multiple network nodes 30 separated by function.

[0067] The transmitting unit 110 includes the function of generating a signal to be transmitted to the terminal 20 or other network node 30 and transmitting the signal by wire or wireless. The receiving unit 120 includes the function of receiving various signals transmitted from the terminal 20 or other network node 30 and obtaining information from the received signal, for example, information from a higher layer. A communication unit including the transmitting unit 110 and the receiving unit 120 may be configured.

[0068] The setting unit 130 stores pre-configured setting information and various setting information to be transmitted to the terminal 20 in a storage device, and reads them from the storage device as needed.

[0069] The control unit 140 performs the processes described in the embodiment. The control unit 140 also performs processing related to communication with the terminal 20. The signal transmission function unit of the control unit 140 may be included in the transmission unit 110, and the signal reception function unit of the control unit 140 may be included in the reception unit 120.

[0070] <Terminal 20> Figure 7 is a diagram showing an example of the functional configuration of terminal 20. As shown in Figure 7, 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 Figure 7 is merely an example. The functional classifications and names of the functional units can be anything as long as they can perform the operations according to the embodiment of the present invention. In addition, the communication device that becomes the resource holder 20 may have a functional configuration similar to that of terminal 20.

[0071] The transmitting unit 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiving unit 220 wirelessly receives various signals and obtains signals from higher layers from the received physical layer signals. The receiving unit 220 also has the function of receiving control signals or reference signals transmitted from the network node 30. A communication unit including the transmitting unit 210 and the receiving unit 220 may be configured.

[0072] The setting unit 230 stores various setting information received from the network node 30 by the receiving unit 220 in its storage device and reads it from the storage device as needed. The setting unit 230 also stores pre-configured setting information.

[0073] The control unit 240 performs the processing described in the embodiment. The signal transmission function in the control unit 240 may be included in the transmission unit 210, and the signal reception function in the control unit 240 may be included in the reception unit 220.

[0074] (Hardware Configuration) The block diagrams (Figures 6 and 7) used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may be realized by combining the one device or the multiple devices with software.

[0075] Functions include, but are not limited to, judgment, decision, determination, calculation, calculation, processing, derivation, investigation, exploration, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, assumption, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission is called a transmitting unit or transmitter. In all cases, as mentioned above, the method of implementation is not particularly limited.

[0076] For example, the base station 10, network node 30, terminal 20, etc. in one embodiment of the present disclosure may function as a computer that processes the wireless communication method of the present disclosure. Figure 8 is a diagram showing an example of the hardware configuration of the base station 10 and terminal 20 according to one embodiment of the present disclosure. The network node 30 may have a hardware configuration similar to that of the base station 10. The above-mentioned base station 10 and 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.

[0077] In the following explanation, the term "device" can be replaced with "circuit," "device," "unit," etc. The hardware configuration of the base station 10 and terminal 20 may include one or more of the devices shown in the figure, or it may be configured without some of the devices.

[0078] Each function in the base station 10 and terminal 20 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and storage device 1002, which allows the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of data reading and writing in the storage device 1002 and auxiliary storage device 1003.

[0079] The processor 1001 controls the entire computer, for example, by running an operating system. The processor 1001 may consist of a central processing unit (CPU) that includes interfaces with peripheral devices, control devices, arithmetic units, registers, etc. For example, the control unit 140, control unit 240, etc., described above may be implemented by the processor 1001.

[0080] Furthermore, the processor 1001 reads programs (program code), software modules, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes accordingly. The program used is one that causes the computer to execute at least a part of the operations described in the above embodiment. For example, the control unit 140 of the base station 10 shown in Figure 6 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Also, for example, the control unit 240 of the terminal 20 shown in Figure 7 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Although the above-described processes have been explained as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may also be transmitted from the network via a telecommunications line.

[0081] The storage device 1002 is a computer-readable recording medium and may consist of at least one of the following: ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The storage device 1002 may also be called a register, cache, main memory, etc. The storage device 1002 can store executable programs (program code), software modules, etc., for implementing a communication method according to one embodiment of the present disclosure.

[0082] The auxiliary storage device 1003 is a computer-readable recording medium and may consist of at least one of the following: an optical disc 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 multipurpose disk, a Blu-ray® disk), a smart card, flash memory (e.g., a card, a stick, a key drive), a floppy® disk, a magnetic strip, etc. The above-mentioned storage medium may also be a database, server, or other suitable medium that includes at least one of the storage device 1002 and the auxiliary storage device 1003.

[0083] The communication device 1004 is hardware (transmitting / receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, communication module, etc. The communication device 1004 may be configured to include, for example, a high-frequency switch, duplexer, filter, frequency synthesizer, etc., in order to implement at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, the transmitting and receiving antenna, amplifier section, transmitting and receiving section, transmission path interface, etc., may be implemented by the communication device 1004. The transmitting and receiving section may be implemented in a physically or logically separated manner, with a transmitting section and a receiving section.

[0084] The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, LED lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).

[0085] 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 different buses may be configured for each device.

[0086] Furthermore, the base station 10 and terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array), and some or all of each functional block may be realized by such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

[0087] Figure 9 shows an example of the configuration of vehicle 2001. As shown in Figure 9, 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 this disclosure may be applied to a communication device mounted on vehicle 2001, for example, to the communication module 2013.

[0088] The drive unit 2002 consists of, for example, 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, which is operated by the user.

[0089] The electronic control unit 2010 consists of a microprocessor 2031, memory (ROM, RAM) 2032, and communication ports (IO ports) 2033. Signals from various sensors 2021 to 2029 installed in the vehicle 2001 are input to the electronic control unit 2010. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

[0090] Signals from various sensors 2021 to 2029 include current signals from current sensor 2021 for sensing motor current, front and rear wheel rotation speed signals acquired by rotation speed sensor 2022, front and rear wheel air pressure signals acquired by air pressure sensor 2023, vehicle speed signals acquired by vehicle speed sensor 2024, acceleration signals acquired by acceleration sensor 2025, accelerator pedal depression signals acquired by accelerator pedal sensor 2029, brake pedal depression signals acquired by brake pedal sensor 2026, shift lever operation signals acquired by shift lever sensor 2027, and detection signals acquired by object detection sensor 2028 for detecting obstacles, vehicles, pedestrians, etc.

[0091] The Information Service Unit 2012 consists of various devices for providing (outputting) various types of information such as driving information, traffic information, and entertainment information, including a car navigation system, audio system, speakers, television, and radio, and one or more ECUs that control these devices. The Information Service Unit 2012 uses information acquired from external devices via a communication module 2013, etc., to provide various multimedia information and multimedia services to the occupants of the vehicle 2001. The Information Service Unit 2012 may include input devices that accept input from the outside (e.g., keyboard, mouse, microphone, switch, button, sensor, touch panel, etc.) and output devices that perform output to the outside (e.g., display, speaker, LED lamp, touch panel, etc.).

[0092] The driver assistance system unit 2030 consists of various devices that provide functions to prevent accidents or reduce the driver's workload, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System)), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. The driver assistance system unit 2030 also transmits and receives various information via the communication module 2013 to realize driver assistance functions or autonomous driving functions.

[0093] The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via its communication port. For example, the communication module 2013 sends and receives data via the communication port 2033 between the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, the microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021-29 provided in the vehicle 2001.

[0094] 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 external devices. For example, it can send and receive various types of information with external devices 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 or a mobile station.

[0095] The communication module 2013 may transmit at least one of the following to an external device via wireless communication: signals from the various sensors 2021-2028 input to the electronic control unit 2010, information obtained based on said signals, and information based on input from an external source (user) obtained via the information service unit 2012. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc., may also be called input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include the information based on the above input.

[0096] The communication module 2013 receives various information (traffic information, signal information, inter-vehicle information, etc.) transmitted from an external device and displays it on the information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may also be called an output unit, which outputs information (for example, outputs information to devices such as displays and speakers 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 the external device 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 2021-2029, etc., provided in the vehicle 2001.

[0097] <Notes> (Note 1) A network node comprising: a receiving unit that receives a first message requesting a media communication call from a terminal; a control unit that generates first configuration information to be used in a second message requesting a media communication call according to the protocol used on the receiving side, based on the first message; and a transmitting unit that transmits the second message including the first configuration information to a second network node on the receiving side, wherein the receiving unit receives a third message in response to the second message from the second network node; the control unit generates second configuration information to be used in a fourth message in response to the first message according to the protocol used on the sending side, based on the third message; and the transmitting unit transmits the fourth message including the second configuration information to the terminal. (Note 2) The network node according to Note 1, wherein the receiving unit receives the first message from the terminal using a PDU (Packet Data Unit) session established on the user plane; and the transmitting unit transmits the fourth message to the terminal using a PDU session established on the user plane. (Note 3) The network node described in Note 1, wherein the media communication according to the protocol used on the receiving side is IMS (IP Multimedia Subsystem) media communication based on SIP (Session Initiation Protocol), and the first and second configuration information are configuration information based on SDP (Session Initiation Protocol). (Note 4) A terminal having: a transmitting unit that transmits a first message requesting a media communication call to a network node having a function to convert the protocol related to the media communication call, using a PDU (Packet Data Unit) session established on the user plane; and a receiving unit that receives a second message in response to the first message from the network node using a PDU session established on the user plane.(Note 5) A communication method performed by a network node, comprising: receiving a first message from a terminal requesting a media communication call; generating first configuration information to be used in a second message requesting a media communication call according to the protocol used on the receiving side, based on the first message; transmitting the second message containing the first configuration information to a second network node on the receiving side; receiving a third message from the second network node in response to the second message; generating second configuration information to be used in a fourth message in response to the first message, according to the protocol used on the originating side, based on the third message; and transmitting the fourth message containing the second configuration information to the terminal.

[0098] Any of the provisions of Appendix 1 to Appendix 5 can provide a mechanism for reducing the system load in a voice / video communication system in a wireless communication network.

[0099] (Supplement to Embodiments) Embodiments of the present invention have been described above, but the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, substitutions, etc. Specific numerical examples have been used to facilitate understanding of the invention, but 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, and matters described in two or more items may be combined as needed, and matters described in one item may be applied to matters described in another item (as long as they do not contradict each other). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operation of multiple functional units may be physically performed by one part, or the operation of one functional unit may be physically performed by multiple parts. The processing procedures described in the embodiments may be rearranged as long as they do not contradict each other. For the convenience of explaining the processing, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be realized in hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to an embodiment of the present invention and the software operated by the processor of the terminal 20 according to an embodiment of the present invention may be stored in any suitable storage medium such as random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or other appropriate storage medium.

[0100] Furthermore, notification of information is not limited to the embodiments described herein and may be carried out by other means. For example, notification of information may be carried out by physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling), broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or combinations thereof. Also, RRC signaling may be called RRC messages, and may be, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc.

[0101] Each aspect / embodiment described in this disclosure refers to LTE (Long Term Evolution), LTE-A (LTE-Advanced), 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 (where x is, for example, an integer or decimal)), 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 802.20 may apply to at least one system utilizing UWB (Ultra-WideBand), Bluetooth®, or other appropriate systems, and to next-generation systems extended, modified, created, or defined based thereon. Alternatively, multiple systems may be applied in combination (e.g., a combination of at least one of LTE and LTE-A with 5G).

[0102] The processing procedures, sequences, flowcharts, etc., of each aspect / embodiment described herein may be reordered, provided they are consistent with each other. For example, the methods described herein present various step elements in an exemplary order and are not limited to that specific order.

[0103] In this specification, specific operations performed by the base station 10 may, in some cases, be performed by its upper node. In a network consisting of one or more network nodes having a base station 10, it is clear that various operations performed for communication with the terminal 20 can be performed by the base station 10 and at least one of the other network nodes (for example, an MME or S-GW, but not limited to these). Although the above example illustrates the case where there is one other network node besides the base station 10, the other network node may be a combination of multiple other network nodes (for example, an MME and an S-GW).

[0104] The information or signals described in this disclosure may be output from a higher layer (or lower layer) to a lower layer (or higher layer). They may also be input and output via multiple network nodes.

[0105] Input and output information may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information may be overwritten, updated, or appended to. Output information may be deleted. Input information may be transmitted to other devices.

[0106] The determination in this disclosure may be made by a value represented by one bit (0 or 1), by a Boolean value (true or false), or by a numerical comparison (for example, a comparison with a predetermined value).

[0107] Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, and so on, whether they are called software, firmware, middleware, microcode, hardware description languages, or by any other name.

[0108] Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technology (such as coaxial cable, fiber optic cable, twisted pair, or digital subscriber line (DSL)) and wireless technology (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.

[0109] The information, signals, etc. described in this disclosure may be represented using any of the various different techniques. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0110] In addition, terms used 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 the channel and symbol may be a signal (signaling). Also, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, cell, frequency carrier, etc.

[0111] The terms “system” and “network” as used in this disclosure are interchangeable.

[0112] Furthermore, the information, parameters, etc., described in this disclosure may be expressed using absolute values, relative values ​​from a given value, or other corresponding information. For example, wireless resources may be indicated by an index.

[0113] The names used for the parameters described above are not restrictive in any way. Furthermore, the formulas and other expressions using these parameters may differ from those expressly disclosed in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.

[0114] In this disclosure, terms such as "Base Station (BS)", "wireless base station", "base station equipment", "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. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0115] A base station can accommodate one or more (e.g., three) cells. If a base station accommodates multiple cells, the entire coverage area of ​​the base station can be divided into multiple smaller areas, each of which may also be provided with communication services by a base station subsystem (e.g., a Remote Radio Head (RRH)). The terms “cell” or “sector” refer to part or all of the coverage area of ​​at least one of the base station and / or base station subsystems that provide communication services in that coverage.

[0116] In this disclosure, the transmission of information by a base station to a terminal may be interpreted as the base station instructing the terminal to perform control or operation based on the information.

[0117] In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

[0118] 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 several other appropriate terms.

[0119] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may also be a device mounted on a mobile body, the mobile body itself, etc. The mobile body refers to a movable object, and its speed of movement is arbitrary. This also includes the case when the mobile body is stationary. The mobile body includes, but is not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcarts, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones (registered trademark), multicopters, quadcopters, balloons, and items mounted on them. The mobile body may also be a mobile body that moves autonomously based on operation commands. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Furthermore, at least one of the base station and the mobile station may include devices that do 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.

[0120] Furthermore, the term "base station" in this disclosure may be interpreted as "user terminal." For example, the various aspects / embodiments of this 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, D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). In this case, the terminals 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, uplink channel, downlink channel, etc., may be interpreted as side channel.

[0121] Similarly, the term "user terminal" in this disclosure may be replaced with "base station." In this case, the base station may be configured to have the same functions as the user terminal described above.

[0122] As used in this disclosure, the terms “determining” and “determining” may encompass a wide variety of actions. “Determining” may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, or inquiring (e.g., searching in a table, database, or other data structure), or ascertaining. “Determining” may also include receiving (e.g., receiving information), transmitting (e.g., sending information), inputting, outputting, or accessing (e.g., accessing data in memory). Furthermore, "judgment" and "decision" can include considering something as having been "judged" or "decided" after resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" and "decision" can include considering something as having been "judged" or "decided" after some action. Also, "judgment (decision)" can be reinterpreted as "assuming," "expecting," or "considering."

[0123] The terms “connected,” “coupled,” or any variation thereof, mean 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” with each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, “connection” may be reinterpreted as “access.” As used in this disclosure, two elements may be considered to be “connected” or “coupled” with each other using at least one of one or more wires, cables, and printed electrical connections, and, in some non-limiting and non-exclusive examples, electromagnetic energy having wavelengths in the radio frequency domain, microwave domain, and optical (both visible and invisible) domain.

[0124] The reference signal can also be abbreviated as RS (Reference Signal), and may be called a pilot depending on the applicable standard.

[0125] In this disclosure, the phrase "based on" does not mean "based solely on" unless otherwise specified. In other words, the phrase "based on" means both "based solely on" and "based at least on."

[0126] Any reference to elements using the designations “first,” “second,” etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Accordingly, references to the first and second elements do not imply that only two elements may be employed, or that the first element must precede the second element in any way.

[0127] In the configuration of each of the above devices, "means" may be replaced with "part," "circuit," "device," etc.

[0128] Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to mean exclusive OR.

[0129] In this disclosure, if articles are added through translation, such as a, an, and the in English, this disclosure may include the fact that the noun following these articles is plural.

[0130] In this 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 "combine" may be interpreted similarly to "different."

[0131] Each aspect / embodiment described in this disclosure may be used individually, in combination, or switched between as needed during implementation. Furthermore, notification of specific information (e.g., notification that "X is") is not limited to explicit notification, but may also be implicit (e.g., by not providing such notification).

[0132] Although the present disclosure has been described in detail above, it will be 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 intent and scope of the present disclosure as defined by the claims. Therefore, the descriptions in the present disclosure are illustrative and not intended to be restrictive in any way.

[0133] 10 Base station 110 Transmitting unit 120 Receiving unit 130 Setting unit 140 Control unit 20 Terminal 210 Transmitting unit 220 Receiving unit 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 wheel 2008 Rear wheel 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 Rotation speed sensor 2023 Air 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 Driver assistance system unit 2031 Microprocessor 2032 Memory (ROM, RAM) 2033 Communication port (I / O port)

Claims

1. A network node comprising: a receiving unit that receives a first message requesting a media communication call from a terminal; a control unit that generates first configuration information to be used in a second message requesting a media communication call according to the protocol used on the receiving side, based on the first message; and a transmitting unit that transmits the second message including the first configuration information to a second network node on the receiving side, wherein the receiving unit receives a third message in response to the second message from the second network node; the control unit generates second configuration information to be used in a fourth message in response to the first message according to the protocol used on the sending side, based on the third message; and the transmitting unit transmits the fourth message including the second configuration information to the terminal.

2. The network node according to claim 1, wherein the receiving unit receives the first message from the terminal using a PDU (Packet Data Unit) session established on the user plane, and the transmitting unit transmits the fourth message to the terminal using a PDU session established on the user plane.

3. The network node according to claim 1, wherein the media communication according to the protocol used on the receiving side is IMS (IP Multimedia Subsystem) media communication based on SIP (Session Initiation Protocol), and the first configuration information and the second configuration information are configuration information based on SDP (Session Initiation Protocol).

4. A terminal comprising: a transmitting unit that transmits a first message requesting a media communication call to a network node having a function for converting protocols related to media communication calls, using a PDU (Packet Data Unit) session established on the user plane; and a receiving unit that receives a second message in response to the first message from the network node, using a PDU session established on the user plane.

5. A communication method performed by a network node, comprising: receiving a first message from a terminal requesting a media communication call; generating first configuration information to be used in a second message requesting a media communication call according to the protocol used on the receiving side, based on the first message; transmitting the second message containing the first configuration information to a second network node on the receiving side; receiving a third message from the second network node in response to the second message; generating second configuration information to be used in a fourth message in response to the first message, according to the protocol used on the originating side, based on the third message; and transmitting the fourth message containing the second configuration information to the terminal.

Images