Method and device for supporting local service in mobile communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. According to an embodiment described in the present disclosure, provided is a method performed by a session management function (SMF) entity in a mobile communication system. The method comprising the steps of: receiving a protocol data unit (PDU) session establishment request message from a user equipment (UE); in response to receiving the PDU session establishment request message, determining whether a unified data management (UDM) entity and the UE can use an edge application server discovery function (EASDF) entity to perform a network function (NF) search; on the basis of the determination result, searching for and selecting the EASDF entity or a domain name system (DNS) that can provide information about the connection of a local management function (LMF) entity to a user plane (UP); setting DNS handling rule information to the selected EASDF entity; and transmitting, to the UE, a PDU session establishment response message including information about the selected EASDF entity.

Description

Method and device for supporting local services in a mobile communication system

[0001] The present disclosure relates to a method and device for supporting local services in a mobile communication system, and more particularly, to a method and device for searching and selecting local services in a mobile communication system.

[0002] 5G mobile communication technology defines a wide frequency band to enable fast transmission speeds and new services, and can be implemented not only in the sub-6GHz frequency band such as 3.5 gigahertz (3.5GHz), but also in the ultra-high frequency band called millimeter wave (mmWave) such as 28GHz and 39GHz ('Above 6GHz'). In addition, for 6G mobile communication technology, which is called the system after 5G communication (Beyond 5G), implementation in the terahertz band (for example, the 3 terahertz (3THz) band at 95GHz) is being considered to achieve a transmission speed that is 50 times faster than 5G mobile communication technology and an ultra-low latency time that is reduced to one-tenth.

[0003] In the early stages of 5G mobile communication technology, the goal is to support services and satisfy performance requirements for enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine-Type Communications (mMTC). These include beamforming and massive MIMO to mitigate path loss of radio waves in ultra-high frequency bands and increase the transmission distance of radio waves, support for various numerologies (such as operation of multiple subcarrier intervals) and dynamic operation of slot formats for efficient use of ultra-high frequency resources, initial access technology to support multi-beam transmission and wideband, definition and operation of BWP (Bidth Part), new channel coding methods such as LDPC (Low Density Parity Check) codes for large-capacity data transmission and Polar Code for reliable transmission of control information, and L2 pre-processing (L2). Standardization has been made for network slicing, which provides dedicated networks specialized for specific services, and pre-processing.

[0004] Currently, discussions are underway to improve and enhance the initial 5G mobile communication technology in consideration of the services that 5G mobile communication technology was intended to support, and physical layer standardization is in progress for technologies such as V2X (Vehicle-to-Everything) to help autonomous vehicles make driving decisions and increase user convenience based on their own location and status information transmitted by vehicles, NR-U (New Radio Unlicensed) for the purpose of system operation that complies with various regulatory requirements in unlicensed bands, NR terminal low power consumption technology (UE Power Saving), Non-Terrestrial Network (NTN), which is direct terminal-satellite communication to secure coverage in areas where communication with terrestrial networks is impossible, and Positioning.

[0005] In addition, standardization of wireless interface architecture / protocols is in progress for technologies such as intelligent factories (Industrial Internet of Things, IIoT) to support new services through linkage and convergence with other industries, Integrated Access and Backhaul (IAB) that provides nodes for expanding network service areas by integrating wireless backhaul links and access links, Mobility Enhancement technology including Conditional Handover and Dual Active Protocol Stack (DAPS) handover, and 2-step random access (2-step RACH for NR) that simplifies random access procedures. Standardization is also in progress for system architecture / services such as 5G baseline architecture (e.g., Service-based Architecture, Service-based Interface) for grafting Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) that provides services based on the location of the terminal.

[0006] Once these 5G mobile communication systems are commercialized, an explosive increase in connected devices will be connected to the communication network, necessitating enhanced functionality and performance of 5G mobile communication systems and integrated operation of these connected devices. To this end, new research will be conducted on improving 5G performance and reducing complexity, supporting AI services, supporting metaverse services, and drone communications by utilizing eXtended Reality (XR), Artificial Intelligence (AI), and Machine Learning (ML) to efficiently support Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR).

[0007] In addition, the development of these 5G mobile communication systems includes new waveforms to ensure coverage in the terahertz band of 6G mobile communication technology, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), Array Antenna, and Large Scale Antenna, metamaterial-based lenses and antennas to improve the coverage of terahertz band signals, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), Reconfigurable Intelligent Surface (RIS) technology, as well as full duplex technology to improve the frequency efficiency and system network of 6G mobile communication technology, satellite, AI (Artificial Intelligence) from the design stage and AI-based communication technology that realizes system optimization by internalizing end-to-end AI support functions, and ultra-high-performance communication and computing resources to provide services with complexity that exceeds the limits of terminal computing capabilities. It can serve as a basis for the development of next-generation distributed computing technologies that can be realized by utilizing them.

[0008] In a mobile communication system, a network function may need to communicate directly with a specific terminal (e.g., user equipment (UE)) to provide services related to the terminal. To perform this direct communication, the UE may need to create a protocol data unit (PDU) session to establish a user plane connection with the network function. To achieve this, the UE and the network function may need to provide the information necessary to establish the user plane connection.

[0009] According to one embodiment of the present disclosure, a method performed by a session management function (SMF) entity in a mobile communication system is provided, the method comprising: receiving a protocol data unit (PDU) session establishment request message from a user equipment (UE); checking, in response to receiving the PDU session establishment request message, whether a unified data management (UDM) entity and the UE are capable of performing network function (NF) discovery using an edge application server discovery function (EASDF) entity; searching and selecting, based on a result of the checking, an EASDF or a local domain name system (DNS) capable of providing information on a user plane (UP) connection of the local management function (LMF) entity; setting DNS handling rule information in the selected EASDF entity; and sending a PDU session establishment response message including information on the selected EASDF entity to the UE. Includes the action of transmitting.

[0010] According to one embodiment of the present disclosure, a mobile communication system provides a session management function (SMF) entity, the SMF entity including a transceiver and at least one processor operatively connected to the transceiver, wherein the at least one processor receives, through the transceiver, a protocol data unit (PDU) session establishment request message from user equipment (UE), and, in response to receiving the PDU session establishment request message, determines, through the transceiver, whether a unified data management (UDM) entity and the UE are capable of performing network function (NF) discovery using an edge application server discovery function (EASDF) entity, and, based on the determination result, searches for and selects an EASDF or a local domain name system (DNS) capable of providing information on a user plane (UP) connection of the local management function (LMF) entity, and It is configured to set DNS handling rule information for a selected EASDF entity, and transmit a PDU session establishment response message including information about the selected EASDF entity to the UE through the transceiver.

[0011] According to one embodiment of the present disclosure, a terminal can establish a user plane connection with a specific network function. Accordingly, according to one embodiment of the present disclosure, the terminal and the network function can transmit and receive data through a shorter transmission path than control plane signaling, which must always transmit data through an access and mobility management function (AMF). Furthermore, according to one embodiment of the present disclosure, the transmission and reception of relatively large data capacity can be supported through a user plane connection, which can utilize more abundant communication resources (e.g., wireless resources such as time / frequency bands) than the control plane.

[0012] FIG. 1 is a diagram illustrating a 5G system architecture that supports local service discovery and selection according to one embodiment of the present disclosure.

[0013] FIG. 2 is a signal flow diagram for explaining an LMF user plane (UP) service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0014] FIG. 3a and FIG. 3b are signal flow diagrams for explaining an LMF UP service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0015] FIG. 4a and FIG. 4b are signal flow diagrams for explaining an LMF UP service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0016] FIG. 5 is a signal flow diagram for explaining an LMF UP service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0017] FIG. 6 is a block diagram illustrating a UE according to one embodiment of the present disclosure.

[0018] FIG. 7 is a block diagram illustrating a network entity according to one embodiment of the present disclosure.

[0019] The operating principles of the present invention are described in detail with reference to the attached diagram. The terms described below are defined based on their functions within the present invention. These terms may vary depending on the intent or custom of the user or operator, and therefore their definitions should be determined based on the overall content of this specification.

[0020] The terms used in this publication to refer to network entities or network functions, terms referring to messages, terms referring to identification information, and the like are provided for convenience of explanation. Therefore, the present invention is not limited to the terms described below, and other terms that refer to objects with equivalent technical meanings may be used.

[0021] For convenience, the present invention uses terms and names defined in the 5G (5th generation) system standard, but is not limited by the terms and names, and can be equally applied to systems conforming to other standards.

[0022] FIG. 1 is a diagram illustrating a 5G system architecture that supports local service discovery and selection according to one embodiment of the present disclosure.

[0023] Referring to FIG. 1, a 5G system may include various network functions (NFs), and FIG. 1 illustrates some of them, including an access and mobility management function (AMF) (115), a session management function (SMF) (117), a policy control function (PCF), an application function (AF), a unified data management (UDM) (125), a data network (DN), a user plane function (UPF) (121), a (radio) access network ((R)AN) (113), and user equipment (UE) (111). According to one embodiment of the present disclosure, an NF may mean a network entity, a network component, and / or a network resource. Each NF supports the following functions.

[0024] - AMF provides functions for access and mobility management at the UE level, and one UE can be connected to one AMF by default.

[0025] - DN refers to, for example, operator service, Internet access, or third-party service. DN transmits a downlink protocol data unit (PDU) to UPF (121) or receives a PDU transmitted from UE (111) from UPF (121).

[0026] - SMF (117) provides a session management function, and when UE (111) has multiple sessions, each session can be managed by a different SMF. V-SMF (visited SMF) represents the SMF of the visited network based on the subscriber of UE (111). H-SMF (home SMF) represents the SMF of the home network of the subscriber of UE (111).

[0027] - UDM (125) stores user subscription data, policy data, etc.

[0028] - UPF (121) transmits a downlink PDU received from DN to UE (111) via (R)AN (113), and transmits an uplink PDU received from UE (111) to DN via (R)AN (113).

[0029] - AF interacts with the 3GPP core network to provide services (e.g., application influence on traffic routing, access to network capability exposure, and interoperability with policy frameworks for policy control).

[0030] - The edge application server discovery function (EASDF) (119) processes a domain name system (DNS) query transmitted by the UE (111) according to rules provided by the SMF (117). For example, it may perform an operation of forwarding a DNS query transmitted by the UE (111) to a DNS server, receiving a DNS response, transmitting a related report to the SMF (117), and providing a DNS response to the UE (111).

[0031] - The local management function (LMF) (123) can perform operations to support localization service for providing location information of the UE (111).

[0032] FIG. 2 is a signal flow diagram for explaining an LMF user plane (UP) service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0033] The LMF UP service discovery support operation illustrated in FIG. 2 may be an LMF UP service discovery support operation initiated by an LMF (e.g., LMF (123)), which may be based on an LMF-initiated UP connection.

[0034] Referring to FIG. 2, the mobile communication system may include a UE (111), an NG-RAN (113), an AMF (115), a UPF (121), an LMF (123), an SMF (117), a UDM (125), an EASDF (119), and / or a network exposure function (NEF) (200).

[0035] In operation 211, an operation for setting NF deployment information and DNS handling rule information that can be used to create an UP connection between the NF and the UE (111) may be performed between the SMF (117), the UDM (125), the EASDF (119), and the NEF (200) (NF deployment info and the corresponding DNS handling rule configuration). The operation for setting NF deployment information and DNS handling rule information that can be used to create an UP connection between the NF and the UE (111) will be described in detail below with reference to FIG. 5, and therefore, a detailed description thereof will be omitted here.

[0036] At operation 213, the LMF (123) may decide to utilize the user plane (UP) path for positioning to support the LCS service.

[0037] In operation 215, the LMF (123) can transmit user plane information to the AMF (115). In one embodiment, user plane information can be transmitted via Namf_Communication_N1N2Transfer (Namf_Communication_N1N2Transfer(User plane information, EASDF info). In one embodiment, user plane information can include at least one of an LMF positioning address (e.g., fully qualified domain name (FQDN) information, LMF connection-related security information), EASDF information, DNS address information, a data network name (DNN), and single network slice selection assistance information (S-NSSAI). The LMF (123) can check the UE authorization for EAS discovery via EASDF or UE authorization for NF discovery via EASDF included in the UDM (125) to determine whether EASDF information can be provided to the UE (111).

[0038] In operation 217, the AMF (115) transmits information received from the LMF (123) to the UE (111). The information may include at least one of the LMF positioning address, EASDF information, DNS address information, DNN, and S-NSSAI required to obtain LMF address information. For example, the AMF (115) may transmit the information received from the LMF (123) to the UE (111) via DL NAS TRANSPORT.

[0039] In operation 219, the UE (111) may transmit an acknowledgment message including information (e.g., User Plane Positioning Acknowledge) regarding whether the UE (111) can successfully perform UP positioning to the AMF (115). For example, the UE (111) may transmit an acknowledgment message including information regarding whether the UE can successfully perform UP positioning to the AMF (115) via UL NAS TRANSPORT.

[0040] In operation 221, AMF (115) may transmit an acknowledgment message received from UE (111) to LMF (123). For example, AMF (115) may transmit the acknowledgment message received from UE (111) via Namf_N1MessageNotify.

[0041] In operation 223, if the message received from the AMF (115) includes information indicating that the UE (111) can successfully perform UP positioning, the LMF (123) may perform an operation for acquiring UE IP address information (UE ID to UE IP translation service request). For example, by using the UE ID and LMF information (identifier or address information), a service provided by the NEF (200) (e.g., Nnef_UEAddress service) may be called to acquire IP address information allocated to the UE (111) corresponding to the UE ID.

[0042] In operation 225, LMF (123) may instruct UE (111) to perform an operation for securely performing UP positioning using the UE IP address acquired through the above operations (Notification of the UE through the known UE IP address). For example, LMF (123) may transmit a secure UP connection establishment execution indicator to UE (111).

[0043] In operation 227, the UE (111) may perform an operation to establish an UP connection with the LMF (123) (UE establishing a secure user plane connection). For example, the UE (111) may transmit a request to the SMF for creating a PDU session. The PDU session creation request message may include an indicator indicating that it is a request for performing LCS UP positioning. After creating the PDU session, the UE (111) may establish a connection with the LMF (123) that guarantees transport layer security (TLS) through the created PDU session.

[0044] At operation 229, the LMF (123) may notify the AMF (115) that the UP positioning preparation for LCS provision has been successfully completed (the UP connection has been successfully created between the UE (111) and the LMF (123)) (Notify User plane positioning setup).

[0045] In operation 231, AMF (115) can store and manage LCS UP connection context information by including it in UE context information (Store LCS-UP connection context).

[0046] In operation 233, a UE positioning and supplementary service message may be exchanged between the UE (111) and the LMF (123) via the user plane (UE positioning and supplementary service message via user plane).

[0047] FIG. 3a and FIG. 3b are signal flow diagrams for explaining an LMF UP service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0048] The LMF UP service discovery support operation illustrated in FIGS. 3a and 3b may be an LMF UP service discovery support operation initiated by an LMF (e.g., LMF (123)), which may be based on an LMF-initiated UP connection.

[0049] Referring to FIGS. 3A and 3B, the mobile communication system may include a UE (111), an NG-RAN (113), an AMF (115), a UPF (121), an LMF (123), an SMF (117), a UDM (125), an EASDF (119), a NEF (200), and / or a network repository function (NRF) (300).

[0050] In operation 311, the SMF (117), the UDM (125), the EASDF (119), and the NEF (200) may perform an operation to configure NF deployment information and DNS handling rule information that can be used to create an UP connection between the NF and the UE (111) (NF deployment info and the corresponding DNS handling rule configuration). The operation to configure NF deployment information and DNS handling rule information that can be used to create an UP connection between the NF and the UE (111) will be described in detail below with reference to FIG. 5, and therefore, a detailed description thereof will be omitted here.

[0051] In one embodiment, NF deployment information may include at least one of the information shown in Table 1 below. NF deployment information may include information necessary for the NF to establish a connection with the UE (111) on the UP. NF deployment information, which is information necessary for the NF to establish a connection with the UE (111) on the UP, may be expressed as "NF UP connection information" and may also mean NF UP deployment information, which means UP deployment information of the NF.

[0052] Table 1: NF deployment information (NF UP Connection information, NF UP deployment information)

[0053]

[0054] At operation 313, the LMF (123) may determine to utilize the user plane (UP) path for positioning operations to support LCS services. This is because when an LCS service request is transmitted to the core network from an AF, a UE (111), or an LCS client, and the LMF (123) receives a request to perform the service from a relevant NF, the LMF (123) may determine whether to use the UP path. When the LMF (123) determines whether to use the UP path, it may consider information such as the required quality information of the requested LCS service (LCS Quality of Service).

[0055] In operation 315, if the LMF (123) decides to use the UP path, it can request and obtain EASDF related information from the NRF (300) or the SMF (117) (EASDF discovery and selection). For example, the LMF (123) can provide the SMF (117) or the NRF (300) with UP connection related information supported by the LMF (123) (for example, at least one of the information constituting the NF deployment information of Table 1) and obtain EASDF identifier and address information in response thereto. As another example, the LMF (123) can decide to use EASDF information included in local configuration information that is set in advance. In addition, the LMF (123) can check the UE authorization for EAS discovery via EASDF or UE authorization for NF discovery via EASDF included in the UDM (125) to determine whether EASDF information can be provided to the UE (111).

[0056] In operation 317, the LMF (123) may transmit user plane information to the AMF (115). In one embodiment, the user plane information may be transmitted via Namf_Communication_N1N2Transfer (Namf_Communication_N1N2Transfer(User plane information, EASDF info). The user plane information may include at least one of an LMF positioning address (e.g., FQDN information, LMF connection-related security information), EASDF information (EASDF address and identifier information determined in previous operations), DNS address information, DNN, and S-NSSAI.

[0057] In operation 319-1, the AMF (115) transmits information received from the LMF (123) to the UE (111). The information may include at least one of the LMF positioning address, EASDF information, DNS address information, DNN, and S-NSSAI required to obtain LMF address information. For example, the AMF (115) may transmit the information received from the LMF (123) to the UE (111) via DL NAS TRANSPORT.

[0058] In operation 319-2, the UE (111) may transmit an acknowledgment message including information (e.g., User Plane Positioning Acknowledge) regarding whether the UE (111) can successfully perform UP positioning to the AMF (115). For example, the UE (111) may transmit an acknowledgment message including information regarding whether the UE can successfully perform UP positioning to the AMF (115) via UL NAS TRANSPORT.

[0059] In operation 321, AMF (115) may transmit an acknowledgment message received from UE (111) to LMF (123). For example, AMF (115) may transmit the acknowledgment message received from UE (111) via Namf_N1MessageNotify.

[0060] In operation 323, if the message received from the AMF (115) includes information indicating that the UE (111) can successfully perform UP positioning, the LMF (123) may perform an operation for acquiring UE IP address information (UE ID to UE IP translation service request). For example, by using the UE ID and LMF information (identifier or address information), a service provided by the NEF (200) (e.g., Nnef_UEAddress service) may be called to acquire IP address information allocated to the UE (111) corresponding to the UE ID.

[0061] In operation 325, LMF (123) may instruct UE (111) to perform an operation for securely performing UP positioning using the UE IP address acquired through the above operations (Notification the UE through the known UE IP address). For example, LMF (123) may transmit a secure UP connection establishment execution indicator to UE (111).

[0062] In operation 327, the UE (111) may perform an operation to establish an UP connection. Operation 327 may be described in detail as follows.

[0063] In operation 327-1, the UE (111) may transmit a request for PDU session establishment to the SMF (117) (via the AMF (115)) (PDU Session Establishment request (indication to request LCS UP connection, EASDF info)). The PDU session establishment request message may include an indicator indicating that it is a request for performing LCS UP positioning, LMF information (LMF identifier or address), etc.

[0064] In operation 327-2, the SMF (117) may interact with the UDM (125) to perform an authentication procedure and subscriber information verification operation for a PDU session creation request of the corresponding UE (111) (Subscription data retrieval). For example, it may be confirmed whether the UE (111) can perform NF discovery using the EASDF (119). The SMF (117) may check whether the NF discovery can be performed through the EASDF (119) or the UE authorization for EAS discovery via EASDF or the UE authorization for NF discovery via EASDF included in the UDM (125). This information may be set for a specific PDU session or a specific DNN or S-NSSAI for a terminal. In one embodiment, the UE (111) may be able to perform NF discovery using the EASDF (119). For example, the UE (111) can transmit a DNS query message (a DNS query message including FQDN information of the LMF (123)) to the EASDF (119) to obtain UP connection address information of the LMF (123).

[0065] In operation 327-3, the SMF (117) may search and select an EASDF or local DNS capable of providing UP connection address information of the LMF (123) considering the information received from the UE (111) (EASDF or local DNS selection considering LMF info). In performing this operation, the SMF (117) may select EASDF if it has received UE authorization for EAS discovery via EASDF or UE authorization for NF discovery via EASDF from the UDM (125), and if it has not received this information from the UDM (125), it may decide to select a local DNS server other than EASDF and provide it to the UE (111). If the PDU session is a session for UP connection to NF, the SMF (117) may decide to search and select an EASDF that supports NF discovery and provide it to the UE (111).

[0066] In operation 327-4, the SMF (117) can set a DNS handling rule in the EASDF selected in the previous operation (DNS handling rule provisioning). The DNS handling rule information can include at least one of the NF deployment info information in Table 1. In addition, the SMF (117) can obtain DNS security policy or DNS security connection related information (DNS security info) supported by the EASDF and provide it to the UE (111).

[0067] In operation 327-5, the SMF (117) may transmit (via the AMF (115)) the EASDF selected in the previous operation (or information about the EASDF selected in the previous operation) to the UE (111) (PDU Session Establishment response (EASDF info, LMF info)). In one embodiment, the SMF (117) may transmit the EASDF selected in the previous operation (or information about the EASDF selected in the previous operation) to the UE (111) via a PDU Session Establishment response message, and the PDU Session Establishment response message may include not only information about the EASDF (EASDF info) but also information about the LMF (123) (LMF info). When the SMF (119) processes a request for creation of a PDU session for an UP connection to the LMF (123), the SMF (119) may notify the LMF (123) of the occurrence of the corresponding event.

[0068] The UE (111) can obtain address information required for creating an UP connection to the LMF (123) using the EASDF or local DNS received from the SMF (117), and can establish a connection with the LMF (123) that is guaranteed to be secure (e.g., guaranteed by TLS).

[0069] In operation 329, if the LMF (123) successfully creates an UP connection with the UE (111), it can notify the AMF (115) that the UP positioning preparation for LCS provision has been successfully completed (the UP connection has been successfully created between the UE (111) and the LMF (123)) (Notify User plane positioning setup).

[0070] In operation 331, AMF (115) can store and manage LCS UP connection context information by including it in UE context information (Store LCS-UP connection context).

[0071] In operation 333, a UE positioning and supplementary service message may be exchanged between the UE (111) and the LMF (123) via the user plane (UE positioning and supplementary service message via user plane).

[0072] FIG. 4a and FIG. 4b are signal flow diagrams for explaining an LMF UP service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0073] The LMF UP service discovery support operation illustrated in FIGS. 4a and 4b may be an LMF UP service discovery support operation initiated by a UE (e.g., UE (111)), which may be based on a UE-initiated UP connection.

[0074] Referring to FIGS. 4A and 4B, the mobile communication system may include a UE (111), an NG-RAN (113), an AMF (115), a UPF (121), an LMF (123), an SMF (117), a UDM (125), an EASDF (119), and / or a NEF (200).

[0075] In operation 411, the SMF (117), the UDM (125), the EASDF (119), and the NEF (200) may perform an operation to configure NF deployment information and DNS handling rule information that can be used to create an UP connection between the NF and the UE (111) (NF deployment info and the corresponding DNS handling rule configuration). The operation to configure NF deployment information and DNS handling rule information that can be used to create an UP connection between the NF and the UE (111) will be described in detail below with reference to FIG. 5, and therefore, a detailed description thereof will be omitted here.

[0076] In one embodiment, NF deployment information may include at least one of the information shown in Table 1. NF deployment information may include information necessary for the NF to establish a connection with the UE (111) on the UP. NF deployment information, which is information necessary for the NF to establish a connection with the UE (111) on the UP, may be expressed as "NF UP connection information" and may also mean NF UP deployment information, which means UP deployment information of the NF.

[0077] In operation 413, the UE (111) may request LCS through UL NAS signaling and simultaneously transmit an UP positioning initiation indicator indicating a request to perform positioning using an UP connection to the AMF (115). For example, the UP positioning initiation indicator may be transmitted through UL NAS TRANSPORT.

[0078] In operation 415, when the AMF (115) receives an LCS request and a request to perform positioning using an UP connection from the UE (111), the AMF (115) may perform an operation of searching and selecting an LMF that allows the UP connection (LMF selection). For example, the UE (111) may check whether positioning using the UP connection is allowed, and select an LMF that performs UP connection-based positioning among the LMFs locally configured in the AMF (115), or request LMF information (address and identifier) ​​that supports UP connection-based positioning from the NRF. When searching and selecting an LMF that supports UP connection-based positioning, the location information of the UE (111) may be taken into consideration as well.

[0079] At operation 417, AMF (115) may send a request to LMF (123) to create an UP connection for LCS (Nlmf_Locatuib_UPConfig Request).

[0080] In operation 419, if the LMF (123) decides to use the UP path, it may request and obtain EASDF related information from the NRF or SMF (117) and provide it to the AMF (115). In one embodiment, EASDF related information can be transmitted via Namf_Communication_N1N2MessageTransfer (Namf_Communication_N1N2MessageTransfer(User plane information, EASDF or local DNS info (if available)). For example, the LMF (123) can provide the SMF (117) or the NRF with UP connection related information supported by the LMF (123) (for example, at least one of the information constituting the NF deployment information of Table 1), and obtain EASDF identifier and address information in response thereto. As another example, the LMF (123) can decide to use EASDF information included in local configuration information that is set in advance. In addition, the LMF (123) can check the UE authorization for EAS discovery via EASDF or UE authorization for NF discovery via EASDF included in the UDM (125) to determine whether EASDF information can be provided to the UE (111).

[0081] LMF (123) can transmit information on whether positioning can be performed using UP connection to AMF (115) and user plane information. User plane information can include at least one of LMF positioning address (e.g., FQDN information, LMF connection-related security information), EASDF information (EASDF address and identifier information determined in a previous operation), DNS address information, DNN, and S-NSSAI.

[0082] In operation 421, the AMF (115) transmits information received from the LMF (123) to the UE (111). The information may include at least one of the LMF positioning address, EASDF information, DNS address information, DNN, and S-NSSAI required to obtain LMF address information. In one embodiment, the AMF (115) may transmit the information received from the LMF (123) via DL NAS TRANSPORT.

[0083] In operation 423, the UE (111) may perform an operation to establish an UP connection using information received through the AMF (115). A detailed description of operation 423 may be as follows.

[0084] In operation 423-1, the UE (111) may transmit a request for PDU session establishment to the SMF (117) (via the AMF (115)) (PDU Session Establishment request (indication to request LCS UP connection, EASDF or local DNS info)). The PDU session establishment request message may include an indicator indicating that it is a request for performing LCS UP positioning, LMF information (LMF identifier or address), etc.

[0085] As another example, the LMF information provided to the SMF (117) may be provided from the AMF (115) rather than the UE (111). When the AMF (115) receives a PDU session creation request from the UE (111) and includes an indicator indicating that the message is a request for performing LCS UP positioning, the AMF (115) may transmit a PDU session creation request message including the LMF information to the SMF (117).

[0086] In operation 423-2, the SMF (117) may interact with the UDM (125) to perform an authentication procedure and subscriber information verification operation for a PDU session creation request of the corresponding UE (111) (Get the selected LMF info). For example, it may be confirmed whether the UE (111) can perform NF discovery using the EASDF (119). The SMF (117) may check whether the UE (111) can perform NF discovery through the EASDF (119) or the UE authorization for EAS discovery via EASDF or the UE authorization for NF discovery via EASDF included in the UDM (125). This information may be set for a specific PDU session or a specific DNN or S-NSSAI for a UE. The SMF (117) may specify the LMF targeting the UP connection based on the information received through the AMF (115).

[0087] In operation 423-3, the SMF (117) may perform an EASDF or local DNS search and selection operation that can provide UP address information of the UP connection target LMF (EASDF or local DNS selection considering LMF info). If the SMF (117) selects an EASDF, the SMF (117) may set a DNS handling rule for the selected EASDF. The DNS handling rule information may include at least one of the NF deployment info information of Table 1. In addition, the SMF (117) may obtain a DNS security policy or DNS security connection related information (DNS security info) supported by the EASDF and provide it to the UE (111) (via the AMF (115)).

[0088] In operation 423-4, the SMF (117) may transmit (via the AMF (115)) the EASDF or local DNS information selected in the previous operation to the UE (111). When the SMF (117) processes a request for creation of a PDU session for an UP connection to the LMF (123), the SMF (117) may notify the LMF (123) of the occurrence of the corresponding event.

[0089] UE (111) can obtain address information required for creating an UP connection to LMF (123) using EASDF or local DNS received from SMF (117) and establish a connection with LMF (123) that is guaranteed to be secure (e.g., TLS is guaranteed).

[0090] In operation 425, if the LMF (123) successfully creates an UP connection with the UE (111), it can provide a response to operation 417 (Nlmf_Location_UPConfig Response) indicating that UP positioning preparation for LCS provision to the AMF (115) has been successfully completed (that an UP connection has been successfully created between the UE (111) and the LMF (123)).

[0091] In operation 427, AMF (115) can store and manage LCS UP connection context information by including it in UE context information (Store LCS-UP connection context).

[0092] In operation 429, a UE positioning and supplementary service message may be exchanged between the UE (111) and the LMF (123) via the user plane (UE positioning and supplementary service message via user plane).

[0093] FIG. 5 is a signal flow diagram for explaining an LMF UP service discovery support operation in a mobile communication system according to an embodiment of the present disclosure.

[0094] The LMF UP service discovery support operation illustrated in FIG. 5 may be an LMF UP service discovery support operation initiated by a UE (e.g., UE (111)), which may be based on a UE-initiated UP connection.

[0095] Referring to FIG. 5, the mobile communication system may include a UE (111), an EASDF (119), a unified data repository (UDR) (500), a NEF (200), and / or a LMF (123).

[0096] In operation 511, 1. NF (e.g., LMF (123)) may transmit NF deployment information to NEF (200) (NF deployment info create). The NF deployment information may include at least one of the information in Table 2 below.

[0097] [Table 2]

[0098]

[0099] In operation 513, NEF (200) may store NF deployment information received from NF (LMF (123)) in UDR (500) (Store NF deployment info request). For example, NEF (200) may map NF identifier and NF deployment information and store them in UDR (500).

[0100] At operation 515, UDR (500) can provide to NEF (200) that NF deployment information has been successfully stored (Store NF deployment info response).

[0101] At operation 517, the NEF (200) may provide to the NF (LMF (123)) that the NF deployment information has been successfully stored in the UDR (500) (Store NF deployment info response).

[0102] In operation 519, the SMF (117) may transmit an NF deployment information notification service subscription request to the NEF (200) to receive NF deployment information from the NEF (200) (Subscribe to get NF deployment info). The request message may include NF type information, a service identifier (e.g., information indicating an LCS service), etc. The NEF (200) may provide the SMF (117) with information indicating whether the subscription was successfully performed, along with a subscription ID and a notification ID.

[0103] In operation 521, the SMF (117) may use NF deployment information when setting a DNS handling rule in the EASDF used for a specific PDU session. For example, an NF deployment information notification for an NF deployment information notification service subscription performed through a previous operation may be received from the NEF (200), and DNS handling rule information related thereto may be set in the EASDF (119).

[0104] In operation 523, the SMF (117) can set a DNS handling rule in the EASDF (119) used for a specific PDU session and obtain configuration information related to an operation of performing a DNS server role in the EASDF (119). For example, the SMF (117) can obtain DNS security information from the EASDF (119). The operation of the SMF (117) obtaining DNS security information supported by the EASDF (119) can be performed based on various methods as follows.

[0105] When SMF (117) obtains information about EASDF (119) from NRF (Network Repository Function), it can also obtain DNS security information supported by EASDF (119).

[0106] Alternatively, DNS security information supported by EASDF (119) may be locally configured in SMF (117).

[0107] Alternatively, the SMF (117) may obtain DNS security information directly from the EASDF (119) as described in operation 523. In one embodiment, when the SMF (117) selects the EASDF (119) or obtains DNS security information from the EASDF (119), the DNS security method supported by the UE (111) may be taken into consideration.

[0108] FIG. 6 is a block diagram illustrating a UE according to one embodiment of the present disclosure.

[0109] Referring to FIG. 6, the UE may include at least one of a processor (601) that controls the overall operation of the UE, a transceiver (603) including a transmitter and / or a receiver, or a memory (605). The UE is not limited to including only the components illustrated in FIG. 6, and the UE may include more or fewer components than the components illustrated in FIG. 6.

[0110] According to one embodiment of the present disclosure, the transceiver (603) can transmit and receive signals with at least one network entity and / or at least one other UE. The signals transmitted and received between the network entity and the UE may include at least one of control information or data. The transceiver (603) can receive signals through a wireless channel and transmit them to the processor (601), and transmit the signals received from the processor (601) through the wireless channel.

[0111] According to one embodiment of the present disclosure, the processor (601) can control the operation of the UE to perform an operation corresponding to at least one of the embodiments of FIGS. 1 to 5.

[0112] The processor (601), the transceiver (603), and the memory (605) do not necessarily need to be implemented as separate modules, and may of course be implemented as a single module in the form of a single chip. The processor (601) and the transceiver (603) may be electrically connected. The processor (601) may include an application processor (AP) and / or a communication processor (CP).

[0113] According to one embodiment of the present disclosure, the memory (605) can store data such as basic programs, application programs, setting information, etc. for the operation of the UE. The memory (605) can provide the stored data according to a request of the processor (601). The memory (605) can be configured as a storage medium or a combination of storage media such as a ROM (read only memory), a RAM (random access memory), a hard disk, a CD-ROM (compact disc read only memory), and a DVD (digital versatile disc). The memory (605) can include a plurality of memories. The processor (601) can perform at least one of the operations corresponding to the embodiments of the present disclosure based on a program for performing at least one of the operations corresponding to the embodiments of the present disclosure stored in the memory (605).

[0114] FIG. 7 is a block diagram illustrating a network entity according to one embodiment of the present disclosure.

[0115] Referring to FIG. 7, the network entity may include at least one of a processor (701) that controls the overall operation of the network entity, a transceiver (703) including a transmitter and / or a receiver, or a memory (705). The network entity is not limited to including only the components illustrated in FIG. 7, and the network entity may include more or fewer components than the components illustrated in FIG. 7.

[0116] According to one embodiment of the present disclosure, the transceiver (703) can transmit and receive signals with at least one other network entity and / or at least one UE. The signals transmitted and received between the at least one other network entity and / or at least one UE may include at least one of control information or data. When the network entity illustrated in FIG. 7 is a base station, the transceiver (703) may include a transceiver for transmitting and receiving wireless signals with the UE, and a transceiver or communication interface for transmitting and receiving signals with other network entities in the core network.

[0117] According to one embodiment of the present disclosure, the processor (701) can control a network entity to perform at least one of the operations corresponding to the embodiments of FIGS. 1 to 5. The processor (701), the transceiver (703), and the memory (705) do not necessarily need to be implemented as separate modules, and may of course be implemented as a single module in the form of a single chip. The processor (701) and the transceiver (703) may be electrically connected. The processor (701) may include an AP and / or a CP.

[0118] According to one embodiment of the present disclosure, the memory (705) can store data such as basic programs, application programs, setting information, etc. for the operation of the network entity. The memory (705) can provide the stored data according to a request of the processor (701). The memory (705) can be configured as a storage medium or a combination of storage media such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD. The memory (705) can include a plurality of memories. The processor (701) can perform at least one of the operations corresponding to the embodiments of the present disclosure based on a program for performing at least one of the operations corresponding to the embodiments of the present disclosure stored in the memory (705).

[0119] A UE according to an embodiment of the present disclosure may be a device of various forms. The UE may include, for example, a portable communication device (e.g., a smartphone), a computer device, a portable multimedia device, a portable medical device, a camera, a wearable device, or a home appliance. The UE according to an embodiment of the present disclosure is not limited to the aforementioned devices.

[0120] It should be understood that the embodiments of the present disclosure and the terminology used herein are not intended to limit the technical features described in the present disclosure to one embodiment, but include various modifications, equivalents, or substitutes of the embodiment. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more items, unless the relevant context clearly indicates otherwise. In the present disclosure, each of the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" can include any one of the items listed together in the corresponding phrase among the phrases, or all possible combinations thereof. Terms such as "first," "second," or "first" or "second" may be used merely to distinguish one component from another, and do not limit the components in any other respect (e.g., importance or order). When a component (e.g., a first component) is referred to as "coupled" or "connected" to another component (e.g., a second component), with or without the terms "functionally" or "communicatively," it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0121] The term "module" used in one embodiment of the present disclosure may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit, for example. A module may be an integrally configured component or a minimum unit or part of a component that performs one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application-specific integrated circuit (ASIC).

[0122] An embodiment of the present disclosure may be implemented as software (e.g., a program) including one or more instructions stored on a storage medium readable by a machine (e.g., a UE). For example, a processor of the machine (e.g., a UE) may call at least one instruction among the one or more instructions stored from the storage medium and execute it. This enables the machine to operate to perform at least one function according to the at least one instruction called. The one or more instructions may include code generated by a compiler or code executable by an interpreter. The machine-readable storage medium may be provided in the form of a non-transitory storage medium. Here, "non-transitory" only means that the storage medium is a tangible device and does not contain a signal (e.g., an electromagnetic wave), and this term does not distinguish between cases where data is stored semi-permanently and cases where it is stored temporarily in the storage medium.

[0123] According to one embodiment, the method according to one embodiment disclosed in the present disclosure may be provided as included in a computer program product. The computer program product may be traded between sellers and buyers as a product. The computer program product may be distributed in the form of a device-readable storage medium (e.g., compact disc read only memory (CD-ROM)) or may be available through an application store (e.g., Play Store). TM ) or directly between two user devices (e.g., smart phones), online distribution (e.g., downloading or uploading). In the case of online distribution, at least a portion of the computer program product may be at least temporarily stored or temporarily created in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

[0124] According to one embodiment, each component (e.g., a module or a program) of the components may include one or more entities, and some of the entities may be separated and placed in other components. According to one embodiment, one or more of the components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (e.g., a module or a program) may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the components identically or similarly to those performed by the corresponding component among the plurality of components prior to integration. According to one embodiment, the operations performed by a module, program, or other component may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

[0125] While the detailed description of the present disclosure has described specific embodiments, it should be understood that various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments, but should be determined not only by the scope of the following claims but also by equivalents thereof. In other words, it will be apparent to those skilled in the art to which the present disclosure pertains that other modifications based on the technical idea of ​​the present disclosure are possible. In addition, each embodiment can be combined and operated with each other as needed. For example, parts of the methods proposed in the present disclosure can be combined with each other to operate a network entity and a UE. In addition, although the embodiments of the present disclosure have been presented based on a 5G, NR system, other modifications based on the technical idea of ​​the embodiments of the present disclosure can be implemented with other systems such as LTE, LTE-A, and LTE-A-Pro systems.

[0126] While the detailed description of this disclosure has described specific embodiments, it should be understood that various modifications are possible without departing from the scope of this disclosure. Therefore, the scope of this disclosure should not be limited to the described embodiments, but should be defined not only by the scope of the claims described below, but also by equivalents thereof.

Claims

1. A method performed by a session management function (SMF) entity in a mobile communication system, An action of receiving a protocol data unit (PDU) session establishment request message from user equipment (UE); In response to receiving the PDU session establishment request message, an action of determining whether a unified data management (UDM) entity and the UE are capable of performing edge application server (EAS) discovery using an edge application server discovery function (EASDF) entity; Based on the above verification results, an action is taken to select an EASDF entity or a local domain name system (DNS); An operation of transmitting DNS handling rule information to the selected EASDF entity; and A method comprising the action of transmitting a response message including information about the selected EASDF entity to the UE.

2. In paragraph 1, The method further comprising the action of obtaining DNS security information from the selected EASDF entity.

3. In paragraph 1, The method further comprising an action of locally configuring DNS security information.

4. In paragraph 1, The method, characterized in that the EASDF entity is an EASDF entity capable of providing information about a user plane (UP) connection of a local management function (LMF) entity.

5. In paragraph 4, The method wherein the response message further includes information about the LMF.

6. In paragraph 4, The method wherein the PDU session establishment request message includes at least one of an indicator or LMF information indicating that the PDU session establishment request message is a request for performing LCS (localization service) UP positioning.

7. In paragraph 1, The above selected EASDF entity is a method that supports the above EAS navigation.

8. In a mobile communication system, for a session management function (SMF) entity, Transmitter and receiver; and comprising at least one processor operatively connected to said transceiver; At least one processor of the above: Through the above transceiver, a protocol data unit (PDU) session establishment request message is received from user equipment (UE), In response to receiving the PDU session establishment request message, the unified data management (UDM) entity and the UE determine, through the transceiver, whether it is possible to perform edge application server (EAS) discovery using an edge application server discovery function (EASDF) entity, Based on the above verification results, select the EASDF entity or the local domain name system (DNS), Transmitting DNS handling rule information to the above selected EASDF entity, and The SMF entity configured to transmit, via the transceiver, a response message including information about the selected EASDF entity to the UE.

9. In paragraph 8, The SMF entity further comprising an operation of obtaining the DNS security information from the selected EASDF entity.

10. In paragraph 8, At least one processor of the above: The SMF entity further configured to locally configure DNS security information.

11. In paragraph 8, The SMF entity is characterized in that the EASDF entity is an EASDF entity capable of providing information about a user plane (UP) connection of a local management function (LMF) entity.

12. In paragraph 11, The above response message is the SMF entity containing further information about the LMF.

13. In paragraph 11, The SMF entity including at least one of an indicator or LMF information indicating that the PDU session establishment request message is a request for performing LCS (localization service) UP positioning.

14. In paragraph 8, The above selected EASDF entity is the SMF entity that supports the above EAS navigation.

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