Method and apparatus for edge service resource selection in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. The present disclosure proposes a method and an apparatus for resource selection by a terminal and a base station in a wireless communication system.

Description

Method and device for selecting edge service resources in a wireless communication system

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system. More specifically, it relates to a method and device for (re)selecting a PSA-UPF (protocol data unit (PDU) session anchor-user plane function) and an EAS (Edge Application Server) in a wireless 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] The embodiment disclosed in the present invention is intended to provide a method and device capable of effectively providing a service in a mobile communication system.

[0009] The present disclosure provides a method and apparatus for (re)selecting a PSA-UPF (protocol data unit (PDU) session anchor-user plane function) and an EAS (Edge Application Server) in a wireless communication system.

[0010] The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0011] According to one embodiment of the present disclosure, a method of operating a network node is provided. The method of operating the network node may include at least one of the following processes. A session management function (SMF) may receive application (re)selection delay time requirement information from an application function (AF) to support (re)selection operations of PAS-UPF and EAS. The information may include a target data network access identifier (hereinafter, ID) (DNAI), N6 delay time requirements required when (re)selecting an application with the target DNAI, and user plane delay time requirements. The SMF may determine whether to perform application (re)selection based on the information. When determining to perform application (re)selection, the SMF may transmit a request message for PSA-UPF (protocol data unit session anchor-user plane function) and EAS-related delay time measurement to a network data analytics function (NWDAF) node.

[0012] According to one embodiment of the present disclosure, a method performed by a session management function (SMF) entity in a communication system, the method comprising: receiving, from a policy control function (PCF) entity, a notify message including a policy and charging control (PCC) rule for measurement of N6 delay, wherein the measurement of N6 delay is a measurement of a connection between at least one user plane function (UPF) entity and a measurement endpoint of a data network (DN);

[0013] A method is disclosed, comprising: receiving edge application server (EAS) deployment information (EDI) for the measurement of the N6 delay from an application function (AF) entity; and transmitting a request message for the measurement of the N6 delay to at least one UPF entity.

[0014] According to one embodiment of the present disclosure, a method performed by a user plane function (UPF) entity in a communication system, the method comprising: receiving, from a session management function (SMF) entity, a request message for measurement of N6 delay, wherein the measurement of N6 delay is a measurement for a connection between at least one UPF entity and a measurement endpoint of a data network (DN), and performing the measurement of N6 delay based on the request message; And in response to the request message, transmitting a report message including a result of the measurement for the N6 delay to the SMF entity; wherein the measurement for the N6 delay is related to a notify message including a policy and charging control (PCC) rule received from a policy control function (PCF) entity and edge application server (EAS) deployment information (EDI) received from an application function (AF) entity.

[0015] According to one embodiment of the present disclosure, in a communication system, a session management function (SMF) entity comprises: a transmitter / receiver; And a control unit coupled with the transceiver; wherein the control unit: receives, from a policy control function (PCF) entity, a notify message including a policy and charging control (PCC) rule for measurement of N6 delay, wherein the measurement of N6 delay is a measurement of a connection between at least one user plane function (UPF) entity and a measurement endpoint of a data network (DN), receives, from an application function (AF) entity, edge application server (EAS) deployment information (EDI) for the measurement of N6 delay, and transmits, to the at least one UPF entity, a request message for the measurement of N6 delay.

[0016] According to one embodiment of the present disclosure, in a communication system, a user plane function (UPF) entity includes: a transceiver; and a control unit coupled to the transceiver; wherein the control unit:

[0017] A UPF entity is disclosed, characterized in that it receives a request message for measurement of N6 delay from a session management function (SMF) entity, wherein the measurement of N6 delay is a measurement of a connection between at least one UPF entity and a measurement endpoint of a data network (DN), performs the measurement of N6 delay based on the request message, and transmits a report message including a result of the measurement of N6 delay to the SMF entity in response to the request message, wherein the measurement of N6 delay is related to a notify message including a policy and charging control (PCC) rule received from a policy control function (PCF) entity and edge application server (EAS) deployment information (EDI) received from an application function (AF) entity.

[0018] Based on the discussion described above, the present disclosure provides a method for processing a control signal in a mobile communication system, which may include: receiving a first control signal transmitted from a base station; processing the received first control signal; and transmitting a second control signal generated based on the processing to the base station.

[0019] The disclosed embodiments provide a device and method capable of effectively providing a service in a mobile communication system. Specifically, the present disclosure provides a device and method for PSA-UPF (protocol data unit (PDU) session anchor-user plane function) and EAS (re)selection in a wireless communication system.

[0020] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure belongs from the description below.

[0021] FIG. 1 is a diagram illustrating a network structure and interface of a 5G system according to an embodiment of the present disclosure.

[0022] FIG. 2 is a diagram illustrating an AF traffic influence request procedure including a data path delay information request according to one embodiment of the present disclosure.

[0023] FIG. 3a is a diagram illustrating a procedure for requesting N6 delay analysis information using NWDAF according to one embodiment of the present disclosure.

[0024] FIG. 3ba is a diagram illustrating a procedure for determining whether to perform a PSA-UPF (re)selection or EAS (re)selection operation considering N6 delay in AF according to an embodiment of the present disclosure, and for measuring and reporting N6 delay through UPF.

[0025] FIG. 3bb is a diagram illustrating a procedure for determining whether to perform a PSA-UPF (re)selection or EAS (re)selection operation considering N6 delay in AF according to an embodiment of the present disclosure, and for measuring and reporting N6 delay through UPF.

[0026] FIG. 3bc is a diagram illustrating a procedure for determining whether to perform a PSA-UPF (re)selection or EAS (re)selection operation considering N6 delay in AF according to an embodiment of the present disclosure, and for measuring and reporting N6 delay through UPF.

[0027] FIG. 4 is a diagram illustrating a PSA-UPF (re)selection decision procedure considering data path delay according to one embodiment of the present disclosure.

[0028] FIG. 5 is a diagram illustrating an AF traffic influence request procedure including a data path delay information request according to one embodiment of the present disclosure.

[0029] FIG. 6 is a diagram illustrating a procedure for requesting N6 delay analysis information using NWDAF according to one embodiment of the present disclosure.

[0030] FIG. 7a is a diagram illustrating an EAS (re)selection decision procedure considering data path delay according to one embodiment of the present disclosure.

[0031] FIG. 7b is a diagram illustrating an EAS (re)selection decision procedure considering data path delay according to one embodiment of the present disclosure.

[0032] FIG. 8 is a diagram illustrating the structure of a terminal according to an embodiment of the present invention.

[0033] FIG. 9 is a diagram illustrating a network entity according to one embodiment of the present invention.

[0034] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the attached drawings.

[0035] In describing this disclosure, descriptions of technical details that are well-known in the technical field to which this disclosure pertains and are not directly related to this disclosure will be omitted. This is to avoid obscuring the gist of this disclosure by omitting unnecessary explanations and to convey it more clearly. Furthermore, the terms described below are defined based on their functions in this disclosure and may vary depending on the intent or custom of the user or operator. Therefore, their definitions should be based on the contents of this specification as a whole.

[0036] In the following description of the present invention, detailed descriptions of known functions or configurations will be omitted if they are deemed to unnecessarily obscure the gist of the present invention. Hereinafter, embodiments of the present invention will be described with reference to the attached drawings.

[0037] The operating principles of the present invention are described in detail below with reference to the attached drawings. 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.

[0038] In describing the embodiments of this disclosure, descriptions of technical details that are well known in the technical field to which this disclosure pertains and are not directly related to this disclosure will be omitted. This is to more clearly convey the gist of this disclosure without obscuring it by omitting unnecessary explanations.

[0039] For the same reason, some components in the attached drawings are exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component do not entirely reflect its actual size. Identical or corresponding components in each drawing are assigned the same reference numbers.

[0040] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided solely to ensure that the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification.

[0041] Hereinafter, a base station (hereinafter referred to as BS) is an entity that performs resource allocation of a terminal, and may be at least one of a gNode B, an eNode B, a Node B (or an xNode B (where x is an alphabet including g or e)), a wireless access unit, a base station controller, a satellite, an airborn, or a node on a network. A user equipment (hereinafter referred to as UE) may include a mobile station (MS), a vehicle, a satellite, an airborn, a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, a downlink (DL) is a wireless transmission path of a signal transmitted from a base station to a terminal, and an uplink (UL) is a wireless transmission path of a signal transmitted from a terminal to an air station. Additionally, a sidelink (SL) may exist, which means a wireless transmission path of a signal transmitted from a terminal to another terminal.

[0042] In addition, although LTE, LTE-A, or 5G systems may be described below as examples, embodiments of the present disclosure may also be applied to other communication systems having similar technical backgrounds or channel types. For example, this may include 5G-Advance or NR-Advance, or 6th generation mobile communication technology (6G) developed after 5G mobile communication technology (or new radio, NR), and the 5G described below may also include existing LTE, LTE-A, and other similar services. In addition, the present disclosure may be applied to other communication systems with some modifications within a range that does not significantly deviate from the scope of the present disclosure, as determined by a person having skilled technical knowledge.

[0043] At this time, it will be understood that each block of the processing flowchart drawings and combinations of the flowchart drawings can be performed by computer program instructions. These computer program instructions can be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment create a means for performing the functions described in the flowchart block(s). These computer program instructions can also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce a manufactured item that includes an instruction means for performing the functions described in the flowchart block(s). Since the computer program instructions may be installed on a computer or other programmable data processing device, a series of operational steps may be performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for performing the functions described in the flowchart block(s) may also provide steps for performing the functions described in the flowchart block(s).

[0044] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for performing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions described in the blocks may occur out of order. For example, two blocks depicted in succession may actually be executed substantially concurrently, or the blocks may sometimes be executed in reverse order, depending on their respective functions.

[0045] Here, the term '~ part' used in the present embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and the '~ part' performs certain roles. However, the '~ part' is not limited to software or hardware. The '~ part' may be configured to be on an addressable storage medium and may be configured to play one or more processors. Therefore, as an example, the '~ part' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and '~ parts' may be combined into a smaller number of components and '~ parts' or further separated into additional components and '~ parts'. Additionally, the components and '~parts' may be implemented to activate one or more CPUs within a device or secure multimedia card. In addition, in an embodiment, the '~part' may include one or more processors.

[0046] In the following description, terms used to identify connection nodes, terms referring to network entities or network functions (NFs), terms referring to messages, terms referring to interfaces between network objects, terms referring to various identification information, etc. are provided as examples for convenience of explanation. Therefore, the present disclosure is not limited to the terms described below, and other terms referring to objects having equivalent technical meanings may be used.

[0047] For convenience of explanation below, some terms and names defined in the 3rd generation partnership project (3GPP) LTE (long term evolution) standard and / or 3GPP NR (new radio) standard may be used. However, the present disclosure is not limited to the above terms and names, and can be equally applied to systems conforming to other standards.

[0048] Certain terms used in the following description are provided to aid in understanding the present disclosure, and the use of such specific terms may be changed to other forms without departing from the technical spirit of the present disclosure.

[0049] 3GPP, responsible for cellular mobile communications standards, is currently standardizing a new core network architecture called 5G Core (5GC) to facilitate the evolution of 4G LTE systems to 5G systems. Compared to the Evolved Packet Core (EPC), the network core for 4G, 5GC supports the following differentiated features:

[0050] 5GC introduces the Network Slice feature. As a requirement of 5G, 5GC must support various types of terminal types and services (e.g., enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communications (URLLC), and massive Machine Type Communications (mMTC)). Each of these terminals / services has different requirements for the core network. For example, eMBB services may require high data rates, while URLLC services may require high reliability and low latency. To meet these diverse service requirements, Network Slice technology has been proposed.

[0051] Network slicing can refer to a method of virtualizing a single physical network to create multiple logical networks (e.g., network slices). An activated network slice can be called a network slice instance, and each network slice instance (hereinafter referred to as NSI) can have different characteristics. By configuring a network function (hereinafter referred to as NF) for each NSI according to its characteristics, a mobile communication operator can satisfy various service requirements according to terminal / service. For example, a mobile communication operator can efficiently support various 5G services (e.g., eMBB, URLLC, or mMTC) by allocating an NSI according to the characteristics of the service required for each terminal.

[0052] 5GC can easily support the network virtualization paradigm by separating the mobility management function and the session management function. In 4G LTE, all terminals can receive services from the network through signaling exchanges with a single core entity called the mobility management entity (MME), which is responsible for registration, authentication, mobility management, and session management. In 5G, the number of terminals (including, for example, MTC terminals) will explode, and the mobility and traffic / session characteristics that must be supported depending on the terminal type will become more specialized. Therefore, supporting all functions from a single entity (e.g., MME) will inevitably reduce scalability by adding entities for each required function. Therefore, various functions are being developed based on a structure that separates the mobility management function and session management function to improve scalability in terms of the functional / implementation complexity and signaling load of the core entity responsible for the control plane.

[0053] FIG. 1 is a diagram illustrating a network structure and interface of a 5G system according to an embodiment of the present disclosure.

[0054] A network entity included in the network structure of the 5G system of Fig. 1 may include a network function (hereinafter referred to as NF) depending on the system implementation.

[0055] Referring to FIG. 1, the network structure of a 5G system may include various network entities. For example, a 5G system may include at least one of an authentication server function (AUSF) entity, an access and mobility management function (AMF) entity, a session management function (SMF) entity, a policy control function (PCF) entity, an application function (AF) entity, a unified data management (UDM) entity, a data network (DN), a network exposure function (NEF) entity, a network slicing selection function (NSSF) entity, a user plane function (UPF) entity, a (radio) access network (R)AN), or a terminal (e.g., a user equipment (UE or terminal).

[0056] Each NF entity in a 5G system can support the following functions:

[0057] AUSF can process and store data for UE authentication.

[0058] AMF provides functions for UE-level access and mobility management, and one UE can be connected to one AMF. Specifically, the AMF provides signaling between core network (CN) nodes for mobility between 3GPP access networks, termination of radio access network (RAN) control plane (CP) interfaces (e.g., N2 interfaces), termination of non-access stratum (NAS) signaling (N1), NAS signaling security (NAS ciphering and integrity protection), AS security control, registration management (e.g., registration area management), connection management, idle mode UE reachability (which may include, for example, control and performance of paging retransmission), mobility management control (e.g., subscription and policy), intra-system mobility and inter-system mobility support, support for network slicing, SMF selection, lawful intercept (e.g., for AMF events and interfaces to LI systems), provision for forwarding of session management (SM) messages between UEs and SMFs, and a transparent proxy for SM message routing. It can support functions such as transparent proxy, access authentication, access authorization including roaming permission check, provision of SMS message transmission between UE and SMSF, security anchor function (SAF) and / or security context management (SCM).Some or all of the functionality of an AMF entity may be supported within a single instance of an AMF entity.

[0059] A DN may represent, for example, an operator service, an Internet connection, or a third-party service. A DN may transmit a downlink protocol data unit (PDU) to a UPF entity, or receive a PDU transmitted from a UE from a UPF entity.

[0060] A PCF entity may receive information about packet flows from an application server and provide functions to determine policies such as mobility management and session management. Specifically, a PCF entity may support functions such as supporting a unified policy framework for controlling network operations, providing policy rules so that control plane function entities (e.g., AMF entities, SMF entities, etc.) can enforce the policy rules, and implementing a front end for accessing relevant subscription information for policy determination within a user data repository (UDR).

[0061] The SMF entity provides session management functionality, and if a UE has multiple sessions, each session can be managed by a different SMF entity. Specifically, the SMF entity may support functions such as session management (e.g., session establishment, modification, and termination, including tunnel maintenance between the UPF entity and the (R)AN node), UE IP (internet protocol) address allocation and management (e.g., including optional authentication), selection and control of UP functions, setting up traffic steering to route traffic from the UPF entity to the appropriate destination, termination of the interface to policy control functions, enforcement of the control portion of policy and quality of service (QoS), lawful intercept (e.g., for SM events and interfaces to the LI system), termination of the SM portion of NAS messages, downlink data notification, initiation of AN specific SM information (e.g., forwarding it to the (R)AN (102) via N2 via the AMF entity), determination of the session and service continuity (SSC) mode of the session, roaming functions, etc. Some or all of the functionality of an SMF entity may be supported within a single instance of an SMF entity.

[0062] A UDM entity can store user subscription data, policy data, etc. A UDM entity (109) can include at least one of two parts: an application front end (FE) and a user data repository (UDR).

[0063] An FE may include a UDM FE responsible for location management, subscription management, and credential processing, and a PCF entity responsible for policy control. A UDR may store data required for the functions provided by the UDM-FE and policy profiles required by the PCF entity. Data stored in the UDR may include user subscription data and policy data, including subscription identifiers, security credentials, access and mobility-related subscription data, and session-related subscription data. A UDM-FE may support functions such as access to subscription information stored in the UDR, authentication credential processing, user identification handling, access authentication, registration / mobility management, subscription management, and SMS management.

[0064] The UPF entity can forward a downlink PDU received from the DN to the UE (101) via the (R)AN, and can forward an uplink PDU received from the UE (101) via the (R)AN to the DN (110). Specifically, a UPF entity may support functions such as an anchor point for intra / inter RAT (radio access technology) mobility, an external PDU session point for interconnection to a data network, a user plane portion of packet routing and forwarding, packet inspection and policy rule enforcement, an uplink classifier to support lawful intercept, traffic usage reporting and routing of traffic flows to the data network, a branching point to support multi-homed PDU sessions, QoS handling for the user plane (e.g., packet filtering, gating, or uplink / downlink rate enforcement), uplink traffic validation (e.g., mapping of service data flows (SDFs) to QoS flows), transport level packet marking in uplink and downlink, downlink packet buffering and downlink data notification triggering. Some or all of the functionality of a UPF entity may be supported within a single instance of a UPF.

[0065] AF entities can interact with the 3GPP core network to provide services (e.g., support for application influence on traffic routing, access to network capability exposure, and interaction with policy frameworks for policy control).

[0066] (R)AN can be a general term for a new radio access network that supports both evolved E-UTRA, an evolved version of 4G radio access technology, and new radio (NR) technology (e.g., gNB).

[0067] The gNB provides functions for radio resource management (e.g., radio bearer control, radio admission control, connection mobility control, dynamic allocation of resources to the UE in uplink / downlink (e.g., scheduling), IP (internet protocol) header compression, encryption and integrity protection of user data streams, selection of an AMF upon attachment of the UE if routing to the AMF is not determined from the information provided to the UE, routing of user plane data to the UPF(s), routing of control plane information to the AMF, connection setup and teardown, scheduling and transmission of paging messages (e.g., originating from the AMF), scheduling and transmission of system broadcast information (e.g., originating from the AMF or operating and maintenance (O&M)), measurement and measurement reporting setup for mobility and scheduling, transport level packet marking in uplink, session management, network It can support functions such as slicing support, QoS flow management and mapping to data radio bearers, support for UEs in inactive mode, NAS message distribution function, NAS node selection function, radio access network sharing, dual connectivity, and tight interworking between NR and E-UTRA.

[0068] UE can refer to a user equipment. A user equipment may be referred to by terms such as terminal, mobile equipment (ME), or mobile station (MS). Furthermore, a user equipment may be a portable device, such as a laptop, mobile phone, personal digital assistant (PDA), smartphone, or multimedia device. Alternatively, it may be a non-portable device, such as a personal computer (PC) or vehicle-mounted device.

[0069] The NEF may provide a means to securely expose internal exposure / re-exposure, application functions, services and capabilities for Edge Computing provided by 3GPP Network Functions (e.g., 3rd party). The NEF may receive information from other NF(s) (e.g., based on the exposed capability(s) of other NF(s)). The NEF may store the received information as structured data using a standardized interface to a data storage network function. The stored information may be re-exposed by the NEF entity to other NF entity(s) and AF entity(ies) and may be used for other purposes such as analysis, etc.

[0070] NRF can support service discovery. NF can receive NF discovery requests from NF instances and provide information about discovered NF instances to NF instances. It can also maintain a list of available NF instances and the services they support.

[0071] In FIG. 1, for convenience, a reference model is illustrated for a case where a UE accesses one DN using one PDU session, but the present disclosure is not limited thereto and may include a case where one or more DNs are accessed using one or more PDU sessions.

[0072] A UE can access two or more (e.g., local and central) data networks simultaneously using multiple PDU sessions. In this case, two or more SMFs can be selected for different PDU sessions. However, each SMF can control both the local UPF and the central UPF within the PDU session.

[0073] A UE can access two or more (e.g., local and central) data networks simultaneously within a single PDU session.

[0074] In the 3GPP system, a conceptual link connecting NFs within a 5G system can be defined as a reference point. For example, the reference point(s) included in the 5G system (100) of FIG. 1 may be as follows.

[0075] - N1: Reference point between UE and AMF

[0076] - N2: Reference point between (R)AN and AMF

[0077] - N3: Reference point between (R)AN and UPF

[0078] - N4: Reference point between SMF and UPF

[0079] - N5: Reference point between PCF and AF

[0080] - N6: Reference point between UPF and DN

[0081] - N7: Reference point between SMF and PCF

[0082] - N8: Reference point between UDM and AMF

[0083] - N9: Reference point between two core UPFs

[0084] - N10: Reference point between UDM and SMF

[0085] - N11: Reference point between AMF and SMF

[0086] - N12: Reference point between AMF and AUSF

[0087] - N13: Reference points between UDM and AUSF

[0088] - N14: Reference point between two AMFs

[0089] - N15: Reference point between PCF and AMF in non-roaming scenario, reference point between PCF and AMF in visited network in roaming scenario.

[0090] FIG. 2 is a diagram illustrating an AF traffic influence request procedure including a data path delay information request according to one embodiment of the present disclosure.

[0091] In step 1, the AF may generate an AF request message (e.g., an AF request message). The AF may include the delay requirements of the data path, such as N6 delay information required by the application, or may generate the AF request message based on the delay requirements of the data path.

[0092] In step 2, the AF may transmit a message (e.g., Nnef_Traffic Influence_Create and / or Update and / or Delete message) to the NEF. The message may include at least one of data path delay requirements, such as AF influence data or N6 delay requirement information. Specifically, the AF may transmit, through the NEF, requirement information for determining whether to perform (re)selection considering the N6 delay (e.g., N6 delay) between the target DNAI and the PSA-UPF when selecting the PSA-UPF in the SMF. The delay requirement (e.g., N6 delay requirements) of the N6 data path may include at least one of the following information.

[0093] (1) Maximum N6 data path latency: The value of the maximum data path latency may refer to the target latency of the N6 data path targeted by the AF. If the PSA-UPF can be (re)selected by the SMF through the AF influence request, the data path latency between the (re)selected PSA-UPF and DN (EAS) may be less than or equal to the value of the maximum data path latency provided in the requirement information. The SMF may obtain the predicted latency between the (re)selected PSA-UPF and DN (EAS) as the terminal moves. The SMF may use a pre-calculated value for the predicted latency or obtain it by requesting the NWDAF. The SMF may check whether the predicted latency between DN (EAS) and PSA-UPF satisfies the requirement for the requested data path latency and decide whether to (re)select the PSA-UPF.

[0094] (2) Minimum delay preference indicator for N6 data path: When SMF selects UPF or PSA-UPF, AF may preferentially select UPF or PSA-UPF with minimum delay of N6 data path for data path between DN (EAS) and UPF or PSA-UPF.

[0095] If the N6 data path delay requirements (e.g., N6 delay requirements) or N6 latency (e.g., N6 delay) are not provided by the AF to the network and thus the N6 data path cannot be directly measured, the AF may send (or forward) information related to the end-to-end (e2e) delay requirements (e.g., e2e delay requirement) or user plane data path delay requirements for UPF selection to the SMF. The SMF may decide whether to request some or all of the received information to the NWDAF based on the received information (e.g., at least one of the N6 delay, the N6 data path delay requirements, or the e2e delay requirements).

[0096] The AF may transmit (or forward) class information related to user plane latency requirements and N6 path latency requirements for PSA-UPF (re)selection to the network. For example, at least one of ASSURED (0) or BEST EFFORT (1) information may be included in at least one of the N6 data path latency or user plane latency-related requirements. Alternatively, class information regarding whether it is ASSURED (0) or BEST EFFORT (1) may be added to the data path latency requirements related to UPF (re)selection provided by the AF.

[0097] When AF requests SMF to perform UPF (re)selection operation based on the delay time requirement of e2e data path according to the policy of the service provider, etc., the e2e data path delay time requirement including maximum e2e data path delay time, minimum e2e data path delay time preference indicator, e2e data path delay time class information, etc. may be transmitted (or delivered) together with the N6 data path delay time requirement or added within the N6 data path delay time requirement.

[0098] In step 3a, NEF may store and / or update and / or remove data path delay related information, including N6 delay requirement information, in the UDR.

[0099] In step 3b, NEF may send a response message to AF (e.g., Nnef_Traffic Influence_Create and / or Update and / or Delete messages).

[0100] In step 4, the UDR may send a notification message (e.g., Nudr_DM_Notify) to the PCF subscribed to the data path delay information change notification service. At this time, a change in data path delay information may occur.

[0101] In step 5, the PCF may send an update confirmation message (e.g., an Npcf_SMPolicyControl_UpdateNotify message) to the SMF. The message may include at least one of information related to AF-influenced traffic steering enforcement control, or information related to data path delay requirements, including N6 delay requirement information. Specifically, the PCF may send the SMF a PCC rule including AF-influenced traffic steering enforcement control information and traffic steering control information. The AF-influenced traffic steering enforcement control information may include at least one of the following information.

[0102] (1) DNAI (data network access identifier) ​​list

[0103] (2) Traffic steering policy identifier

[0104] (3) N6 traffic routing information

[0105] (4) AF subscription information for UP change events

[0106] (4-1) Early notification or late notification

[0107] (4-2) Notification target address and notification correlation ID

[0108] (4-3) Indicator for whether AF response is required (AF acknowledgment)

[0109] Traffic steering control information may include at least one of the following information.

[0110] (1) Terminal IP address maintenance indicator

[0111] (1-1) SMF can use the terminal IP address maintenance indicator to determine whether to (re)select PSA.

[0112] (2) Shortest data path delay preference indicator

[0113] (2-1) SMF can select the PSA-UPF with the minimum N6 data path delay time using the shortest N6 data path delay preference indicator.

[0114] (3) Target N6 delay requirement

[0115] (3-1) SMF can use the target N6 delay requirement to decide whether to (re)select PSA.

[0116] In step 6, the SMF may perform an operation for (re)selection of the PSA-UPF (e.g., PSA UPF selection) based on the N6 delay requirement information. The SMF may perform user plane (re)selection of the PDU session. To perform user plane (re)selection, the SMF may perform at least one of the following operations. Here, the configuration information for (re)selection of the PSA-UPF may mean traffic routing reconfiguration.

[0117] (1) At least one addition, change, or deletion of a UPF (e.g., ULCL UPF (uplink classifier UPF) or branching point UPF (branching point UPF));

[0118] (2) New IPv6 allocation for terminals with IPv6 (internet protocol version 6) multi-homing applied

[0119] (3) Change to UPF belonging to target DNAI provided with new traffic steering rules.

[0120] (4) Subscription to the AMF area of ​​interest notification service

[0121] (5) Selection of PSA-UPF that satisfies the requested data path delay time

[0122] (6) SMF may consider re-selecting PSA-UPF when the terminal performs a handover (HO) procedure, when the terminal leaves or enters an AOI, or when the terminal sends a registration request due to a change in location.

[0123] (7) When deciding to re-select a PSA-UPF, it is possible to decide whether to re-select a PSA-UPF based on the requested data path delay time, and select a PSA-UPF with the minimum data path delay time among multiple PSA-UPFs, or a PSA-UPF that satisfies the required delay time.

[0124] FIG. 3a is a diagram illustrating a procedure for requesting N6 delay analysis information using NWDAF according to one embodiment of the present disclosure.

[0125] NWDAF can request N6 delay from UPF or request e2e (end-to-end) delay (or latency) information from AF. Based on N6 delay information collected from UPF or e2e delay information collected from AP, NWDAF can provide predicted network delay information to SMF based on at least one of terminal location, RAT (radio access technology) type, RAN node ID, and UPF ID.

[0126] According to an embodiment of the present invention, the SMF may receive at least one of N6 data path latency requirement information, user plane latency requirement information, and e2e latency requirement information for (re)selection of PSA-UPF from the AF. The SMF may determine whether to request some or all of the latency analysis information (e.g., analytics information) of the data path to the NWDAF based on the latency requirement of the data path. The NWDAF may transmit (or forward) the analyzed data path latency information to the SMF based on the request. Through this, the SMF may receive or be forwarded information about the actual delayed data path latency.

[0127] The SMF can receive requests from the AF (e.g., e2e latency requirements or N6 data path latency-related requirements). Based on the requests, the SMF can send (or forward) information to the NWDAF.

[0128] In step 1, the SMF or other consumer NFs may send a request message for data path prediction information to the NWDAF. The request message may include information about at least one of the current UE location, RAT type, RAN node ID, UPF ID, SMF ID, and UPF service area.

[0129] According to one embodiment of the present disclosure, when there is an e2e delay requirement, the SMF may request the NWDAF to measure the e2e delay. The SMF may transmit (or forward) to the NWDAF at least one of a request message (e.g., an Nnwdaf_AnalyticsInfo_Request message) or a subscription message (e.g., an Nnwdaf_AnalyticsSubscription_Subscribe message) including network delay information (e.g., Analytics ID = DN Performance, UL / DL Performance data including average / maximum packet delay) to measure the e2e delay that occurs when connecting to a candidate PSA-UPF for each Target DNAI.

[0130] According to one embodiment of the present invention, when there is an N6 delay requirement (e.g., requirement related to N6 data path delay time), the SMF may request N6 delay time related analysis information to the NWDAF. The SMF may send (or forward) at least one of a request message (e.g., an Nnwdaf_AnalyticsInfo_Request message) or a subscription message (e.g., an Nnwdaf_AnalyticsInfo_Request / Nnwdaf_AnalyticsSubscription_Subscribe message) including network delay information (e.g., Analytics ID = Analytics ID = QoS Sustainability, average / maximum N6 delay) to the NWDAF for measuring the N6 delay that occurs when connecting to a candidate PSA-UPF for each Target DNAI.

[0131] When performing a PSA-UPF (re)selection operation based on the N6 delay requirement, the SMF may request the expected delay information on the user plane based on the N3 and N9 segments.

[0132] In step 2a, if e2e delay measurements for each Candidate PSA-UPF associated with the Target DNAI are possible, the NWDAF can send (or forward) a subscription message (e.g., a Naf_EventExposure_Subscribe message) to the AF for event subscription. The subscription message can be sent to the AF via the NEF. The subscription message can include information such as Event ID=Performance Data, UL / DL Performance data including average / maximum packet delay, etc.

[0133] When e2e delay is measured for each Candidate PSA-UPF associated with Target DNAIs, AF can send (or forward) delay information (e.g., average and / or maximum packet delay for an application information) to NWDAF via a notification message (e.g., Naf_EventExposure_Notify message).

[0134] In step 2b, the NWDAF can send (or forward) an event subscription message (e.g., a Nupf_EventExposure_Subscribe message) to the UPF to request N6 delay and user plane latency measurements for each Candidate PSA-UPF associated with the Target DNAIs. The event subscription message can include information such as Event ID = QoS Monitoring, QoS flow Packet Delay, UL / DL N6 delay, and UL / DL UP latency.

[0135] When the N6 delay per Candidate PSA-UPF connected to the Target DNAIs is measured, the UPF may send (or forward) to the NWDAF via a notification message (e.g., a Nupf_EventExposure_Notify message) at least one of the average / maximum N6 delay for an application or user plane delay information between the Candidate PSA-UPF and the terminal.

[0136] In step 2c, the NWDAF may analyze (or measure or calculate) at least one of N6 or user plane delay information or e2e delay information based on requirement information received or transmitted from the SMF. The N6 or user plane delay information may be analyzed by calculating an average of N6 delay information measured over a period of time based on information of a Candidate PSA-UPF associated with a specific DNAI, or may be analyzed (or measured or calculated) based on the maximum N6 or user plane delay information that occurred over a period of time in a specific Candidate PSA-UPF.

[0137] In step 3, NWADF may forward the analyzed N6 or user plane latency information to SMF via Nnwdaf_AnalyticsInfo_Request Response or Nnwdaf_AnalyticsSubscription_Notify message, which may include information on at least one of estimated DN performance, N6 delay, UP delay (UPF), or e2e latency (AF), or QoS Sustainability.

[0138] In step 4, the SMF can perform PSA-UPF (re)selection based on the N6 or user plane delay information received from the NWDAF.

[0139] FIGS. 3ba, 3bb, and 3bc are diagrams illustrating a method for determining whether to perform a PSA-UPF (re)selection or EAS (re)selection operation based on N6 delay in AF according to an embodiment of the present disclosure, and an N6 delay measurement and reporting operation through UPF.

[0140] The AF can forward requirements information related to N6 delay measurement to the PCF. The PCF can forward PCC rule updates containing N6 delay measurement operations or QoS monitoring policies to the SMF. The UPF can perform QoS monitoring operations for N6 traffic parameter measurement or N6 traffic parameter measurement. The UPF can report QoS monitoring reporting values ​​directly to the SMF or report them to the SMF through the NWDAF. Alternatively, the UPF can forward N6 delay measurement values ​​directly to the AF through the NEF upon the AF's request.

[0141] AF can decide whether to perform PSA-UPF (re)selection or EAS (re)selection operation based on N6 delay, depending on user choice or service provider policy.

[0142] In step 1, AF may transmit N6 delay monitoring requirement information including at least one of target N6 delay requirement information, QoS monitoring requirements for N6 delay monitoring, or N6 delay measurement requirements to NEF based on the determined matters. Through this, NEF may transmit (or forward) N6 delay monitoring requirement information or N6 delay measurement requirement information to PCF. N6 delay monitoring requirement information or N6 delay measurement requirement information may be included in AF session related QoS requirement (e.g., AFsessionWithQoS or Nnef_AFsessionwithQoS_Create / Update request) message forwarded from AF to NEF entity. The N6 delay monitoring requirement or N6 delay measurement requirement information may include at least one of an N6 delay support indication (e.g., an N6 delay support indication) in the N6 delay monitoring or N6 delay measurement support information (e.g., an N6 delay Assistance information), an N6 delay calculation method based on a protocol type of an N6 section (e.g., an N6 delay calculation method), an N6 delay reporting period (e.g., an N6 delay reporting period), a jitter reporting condition including exceptional N6 traffic characteristics (e.g., an N6 delay (jitter) reporting condition), or QoS monitoring related information for N6 delay measurement in PCF.

[0143] Methods for calculating N6 delay based on the protocol type of the N6 section (e.g., N6 delay calculation method) may include a method using a timestamp in the RTP control protocol (RTCP) when using a real-time transport protocol (RTP)-based service, a method using timestamp information in the HE (Header Extension) of RTP, or an N6 delay calculation method based on at least one of the One-way Active Measurement Protocol (OWAMP, RFC 4656), the Two-Way Active Measurement Protocol (TWAMP, RFC 5357), or the Simple Two-way Active Measurement Protocol (STAMP, RFC 8762).

[0144] QoS monitoring information may include information indicating a reporting frequency set to an event trigger or periodic. When the N6 latency monitoring requirement information includes information indicating a reporting frequency set to an event trigger, it may include threshold information for at least one of uplink, downlink, or round trip for judgment, and may have a minimum waiting time value between reports. When the N6 latency monitoring requirement information includes information indicating a reporting frequency set to a periodic, the reporting period value may be set to transmit the QoS monitoring parameter to the UPF to perform an action. The parameters for QoS monitoring may include information indicating a notification address related to information related to reporting, a notification correlation ID related to notification, or an indicator indicating whether the UPF directly notified the AF of an event (Direct event notification indication).

[0145] In step 2, the NEF may convey jitter assistance information (e.g., N6 delay Assistance information) to the PCF entity via a policy authorization (e.g., PolicyAuthorization) message to support PSA-UPF (re)selection or EAS (re)selection operation based on N6 delay. The NEF may convey the N6 delay assistance information received via a policy authorization create message (e.g., Npcf_PolicyAuthorization_Create) request or a policy authorization update (e.g., Npcf_PolicyAuthorization_Update) request message to the PCF entity. The NEF may request event reporting to the PCF entity via a policy authorization subscribe (e.g., Npcf_PolicyAuthorization_Subscribe) message to receive service-related reporting, i.e., to receive messages related to jitter-related reporting events occurring in the PCF. NEF can receive N6 delay information directly through UPF or request event reporting to PCF through AF for N6 delay information delivered to SMF. For the above request, NEF can define new jitter reporting-related event IDs (e.g., QoS Monitoring based N6 delay Monitoring reporting or N6 delay measurement reporting) based on measured packet delay to receive jitter support information-related reporting from PCF.

[0146] In Step 3, the PCF can create an authorized QoS Monitoring policy for measuring N6 delay based on QoS monitoring or through traffic monitoring. Alternatively, it can update PCC rules based on N6 delay monitoring requirements. The updated PCC rules can include QoS monitoring parameter information or traffic monitoring information for N6 delay measurement.

[0147] In steps 4 and 5, the PCF may send (or forward) response messages (e.g., Npcf_PolicyAuthorization_Create / Update response or Nnef_AFsessionWithQoS_Create / Update response) to the request messages in steps 1 and 2 to the AF via the NEF.

[0148] In step 6, PCF may send or forward the updated PCC rules to SMF via a Session Policy Adjustment Update Notification (e.g., Npcf_SMPolicyControl_UpdateNotify) request message.

[0149] In steps 7a and 7b, the SMF may send or forward the PCC rules to the UPF via an N4 session creation / modification (e.g., N4 session estalblishment / Modification) request message.

[0150] The above N4 session creation / modification request message may include information for performing QoS monitoring for N6 delay measurement and receiving a result report (e.g., QoS monitoring Report based on N6 delay monitoring requirements) or an N6 traffic parameter measurement report (e.g., N6 Traffic Parameter Measurement Report based on N6 delay Measurement requirements). The SMF may forward the N4 reporting operation (N4 reporting procedure) request message to the UPF through an SRR (Session Reporting Rule) generated based on an updated PCC rule that reflects parameter information related to QoS monitoring or N6 traffic parameter measurement for N6 delay measurement according to an AF request.

[0151] The SMF may send or forward an N4 session creation / modification (e.g., N4 session estalblishment / Modification) request message to each Candidate PSA-UPF (e.g., UPF 1 and UPF 2) for N6 delay measurement for each Candidate PSA-UPF associated with the Target DNAIs. The SMF may send or forward an SRR for N6 delay measurement to each UPF, and the SRR may be included in the request message and sent or forwarded.

[0152] In steps 8a and 8b, each UPF (e.g., UPF1 and UPF2) may send or forward a response message (e.g., N4 session establishment / modification response) to the request message in step 7 to the SMF.

[0153] In step 9, the SMF may transmit a request message for data path prediction information to the NWDAF. The request message may include information about at least one of the current UE location, remote access tool (RAT) type, RAN node ID, UPF ID, SMF ID, or UPF service area. If the SMF has N6 latency requirements (e.g., requirements related to N6 data path latency), the SMF may request N6 latency-related analysis information from the NWDAF. SMF may send (or forward) to NWDAF at least one of a request message (e.g., Nnwdaf_AnalyticsInfo_Request message) or a subscription message (e.g., Nnwdaf_AnalyticsInfo_Request / Nnwdaf_AnalyticsSubscription_Subscribe message) containing network delay information (e.g., Analytics ID = Analytics ID = QoS Sustainability, average / maximum N6 delay) to measure the N6 delay that occurs when connecting to a candidate PSA-UPF per Target DNAI.

[0154] In steps 10a and 10b, the NWDAF may send (or forward) an event subscription message (e.g., a Nupf_EventExposure_Subscribe message) to at least one UPF (e.g., UPF1 and UPF2) to request N6 delay and user plane latency measurements for each Candidate PSA-UPF associated with the Target DNAIs. The event subscription message may include information such as Event ID = QoS Monitoring, QoS flow Packet Delay, UL / DL N6 delay and UL / DL UP latency.

[0155] In steps 11a and 11b, each UPF may transmit (or forward) to the NWDAF via a notification message (e.g., a Nupf_EventExposure_Notify message) at least one of the average / maximum N6 delay for an application or user plane delay information between the Candidate PSA-UPF and the terminal when the N6 delay per Candidate PSA-UPF associated with the Target DNAIs is measured.

[0156] In step 12, NWADF may forward the analyzed N6 or user plane latency information to SMF via Nnwdaf_AnalyticsInfo_Request Response or Nnwdaf_AnalyticsSubscription_Notify message.

[0157] Alternatively, according to one embodiment of the present invention, the SMF may directly receive N6 delay related QoS monitoring reporting or traffic monitoring reporting values ​​from the UPF.

[0158] The SMF can request statistical analysis of N6 delay values ​​monitored by the UPF through the NWDAF from steps 9 to 12, regarding information related to the N6 delays of the Candidate PSA-UPFs connected to the Target DNAIs, or can receive the results of event reporting related to QoS monitoring operations or traffic monitoring operations directly from the UPF in steps 13 and 14. If the results of event reporting related to QoS monitoring operations or traffic monitoring operations are received directly from the UPF, steps 9 to 12 can be omitted.

[0159] Through the above steps, SMF can perform PSA-UPF (re)selection or EAS (re)selection operation considering data path delay.

[0160] FIG. 4 is a diagram illustrating a PSA-UPF (re)selection decision procedure considering data path delay according to one embodiment of the present disclosure.

[0161] The UE can transmit and receive UPF 1 and UL / DL Data.

[0162] In step 1, the SMF may perform a PSA-UPF (re)selection operation based on at least one of the N6 latency requirement received from the AF and the predicted N6 or user plane latency information or e2e latency information received from the NWDAF or UPF.

[0163] In step 1a, the SMF can send (or forward) UPF selection information related to Target DNAI information to the AMF via a request message (e.g., Nsmf_PDUSession_SMContextStatusNotify Request message). In response, the AMF can send (or forward) UPF selection information related to Target DNAI information to the SMF via a response message (e.g., Nsmf_PDUSession_SMContextStatusNotify Response message). The Target DNAI information can be used to select an SMF capable of controlling a UPF connected to the Target DNAI when establishing a PDU session using the same data network name (DNN) and single network slice selection assistance information (S-NSSAI).

[0164] In step 2, the SMF can request the terminal to perform a PDU session termination operation (e.g., a PDU session release procedure) related to UPF1 through the AMF. This request can be made through a transmission message (e.g., a Namf_Communication_N1N2MessageTransfer message) containing N1 SM information. The PDU session termination command (e.g., a PDU Session Release Command) message contained in the N1 SM information can include a cause related to the PDU session re-establishment with the same DN as the PDU session ID.

[0165] In step 3, the AMF can select an SMF based on the Target DNAI information. At this time, the terminal can perform a new PDU session establishment procedure (e.g., a PDU session establishment procedure) related to UPF 2. The SMF can select a new UPF 2 based on the Target DNAI information. At this time, the SMF can perform user plane (re)selection.

[0166] The UE can transmit and receive new UPF2 and UL / DL Data.

[0167] FIG. 5 is a diagram illustrating an AF traffic influence request procedure including a data path delay information request according to one embodiment of the present disclosure.

[0168] In step 1, the AF may generate an AF request message (e.g., an AF request message). The AF may include data path latency requirements, such as N6 latency information required by the application, or may generate an AF request message related to EAS (re)selection based on the data path latency requirements.

[0169] In step 2, the AF may transmit a message (e.g., Nnef_Traffic Influence_Create and / or Update and / or Delete message) to the NEF. The message may include at least one of AF influence data, or N6 delay requirement information, and data path delay requirements. Specifically, the AF may transmit, via the NEF, requirement information for determining whether to perform EAS (re)selection considering the N6 delay between the target DNAI and the PSA-UPF to at least one of the SMF, the L-SMF, or the EASDF (edge ​​application server discovery function). The N6 data path delay requirements (e.g., the N6 delay requirements) may include at least one of the following information:

[0170] (1) Maximum N6 data path latency: The value of the maximum data path latency may refer to the target latency of the N6 data path targeted by the AF. If the SMF can (re)select DN (EAS) through an AF influence request, the data path latency between the (re)selected PSA-UPF and DN (EAS) may be less than or equal to the value of the maximum data path latency provided in the requirement information. The SMF may obtain the predicted latency between the (re)selected PSA-UPF and DN (EAS) as the terminal moves. The SMF may use a pre-calculated value for the predicted latency or obtain it by requesting the NWDAF. At least one of the SMF, L-SMF or EASDF may check whether the predicted latency between DN (EAS) and PSA-UPF satisfies the requirement for the requested data path latency and determine whether to (re)select EAS.

[0171] (2) Minimum delay preference indicator for N6 data path: When at least one of SMF, L-SMF or EASDF selects EAS, AF may preferentially select EAS with minimum delay for the data path between DN (EAS) and PSA-UPF.

[0172] If the N6 data path delay requirements (e.g., N6 delay requirements) or N6 latency (e.g., N6 delay) are not provided by the AF to the network and thus the N6 data path cannot be directly measured, the AF may send (or forward) information related to the end-to-end (e2e) delay requirements (e.g., e2e delay requirement) or user plane data path delay requirements for UPF selection to the SMF. The SMF may decide whether to request some or all of the received information to the NWDAF based on the received information (e.g., at least one of the N6 delay, the N6 data path delay requirements, or the e2e delay requirements).

[0173] The AF may transmit (or forward) class information related to user plane latency requirements and N6 path latency requirements for PSA-UPF (re)selection to the network. For example, at least one of ASSURED (0) or BEST EFFORT (1) information may be included in at least one of the N6 data path latency or user plane latency-related requirements. Alternatively, class information regarding whether it is ASSURED (0) or BEST EFFORT (1) may be added to the data path latency requirements related to UPF (re)selection provided by the AF.

[0174] When AF requests SMF to perform UPF (re)selection operation based on the delay time requirement of e2e data path according to the policy of the service provider, etc., the e2e data path delay time requirement including maximum e2e data path delay time, minimum e2e data path delay time preference indicator, e2e data path delay time class information, etc. may be transmitted (or delivered) together with the N6 data path delay time requirement or added within the N6 data path delay time requirement.

[0175] In step 3a, NEF may store and / or update and / or remove data path delay related information, including N6 delay requirement information, in the UDR.

[0176] In step 3b, NEF may send a response message to AF (e.g., Nnef_Traffic Influence_Create and / or Update and / or Delete messages).

[0177] In step 4, the UDR may send a notification message (e.g., a Nudr_DM_Notify message) to a PCF subscribed to the data path delay information change notification service. At this time, a change in data path delay information may occur.

[0178] In step 5, the PCF may send an update confirmation message (e.g., an Npcf_SMPolicyControl_UpdateNotify message) to the SMF. The message may include at least one of information related to AF-influenced traffic steering enforcement control, or information related to data path delay requirements, including N6 delay requirement information. Specifically, the PCF may send the SMF a PCC rule including AF-influenced traffic steering enforcement control information and traffic steering control information. The AF-influenced traffic steering enforcement control information may include at least one of the following information.

[0179] (1) DNAI (data network access identifier) ​​list

[0180] (2) Traffic steering policy identifier

[0181] (3) N6 traffic routing information

[0182] (4) AF subscription information for UP change events

[0183] (4-1) Early notification or late notification

[0184] (4-2) Notification target address and notification correlation ID

[0185] (4-3) Indicator for whether AF response is required (AF acknowledgment)

[0186] Traffic steering control information may include at least one of the following information.

[0187] (1) Terminal IP address maintenance indicator

[0188] (1-1) SMF can use the terminal IP address maintenance indicator to determine whether to (re)select EAS.

[0189] (2) Shortest data path delay preference indicator

[0190] (2-1) SMF or L-SMF or EASDF can select the EAS with the minimum N6 data path delay time by using the shortest N6 data path delay preference indicator.

[0191] (3) Target N6 delay requirement

[0192] (3-1) SMF or L-SMF or EASDF can use the target N6 delay requirement to decide whether to (re)select EAS.

[0193] The SMF can receive or be forwarded information about candidate EASs (e.g., an array of FQDN ranges and / or an array of EAS IP address ranges) in a DNS response message from the EASDF. The SMF can perform EAS (re)selection based on the N6 latency requirement information received or forwarded from the AF. At this time, the SMF can be based on the DNS (domain name system) query information requested by the terminal. The SMF can request the EASDF for a DNS handling rule. Alternatively, the SMF can request EAS (re)selection based on the N6 latency requirement information in the BaselineDNSPattern. The SMF can receive predicted N6 latency information for a specific IP range from a network operator. Alternatively, the SMF can transmit (or forward) the N6 latency requirement information to the EASDF based on the predicted N6 latency information received or forwarded through the NWADF.

[0194] Depending on the settings of the service provider and network operator, N6 latency requirement information may be transmitted (or forwarded) from the NEF to the SMF. At this time, at least one of steps 4 or 5 may be omitted. The requirement information for determining whether to perform EAS (re)selection considering the N6 latency may be included and forwarded within the EAS Deployment Information or may be forwarded via an AF request message (e.g., an AF request message) without using the EAS Deployment Information.

[0195] Depending on the settings of the service provider and network operator, the selection of an appropriate EAS that satisfies the service requirements can be performed based on information from EASs in at least one of the SMF or L-SMF. This can be based on at least one of the N6 delay time or e2e delay time requirement information.

[0196] Depending on the settings of the service provider and network operator, the SMF may send (or forward) at least one of the N6 delay requirement information for EAS selection and the EAS selection action indicator within the BaselineDNSPattern information or the DNS message handling rule information to the ESADF. Through this, the SMF can instruct the EASDF to perform EAS selection.

[0197] According to one embodiment of the present invention, the AF may transmit (or forward) information such as user plane latency requirements, N6 latency requirements, or e2e latency requirements to the SMF or L-SMF via the EAS Deployment Information or AF request message. The AF may transmit (or forward) information on the highest priority latency requirements to be considered when selecting an EAS to the SMF or L-SMF via the EAS Deployment Information or AF request message.

[0198] According to one embodiment of the present invention, the AF may transmit (or forward) to the SMF or L-SMF, including IP range information of a specific UE address or UE addresses within a specific region. In this case, the AF may enable specific terminals or terminals in a specific region to perform EAS (re)selection based on service delay requirements.

[0199] FIG. 6 is a diagram illustrating a procedure for requesting N6 delay analysis information using NWDAF according to one embodiment of the present disclosure.

[0200] NWDAF can request N6 delay from UPF or request e2e delay information from AF. Based on N6 delay information collected from UPF or e2e delay information collected from AP, NWDAF can provide SMF with network delay information predicted based on at least one of terminal location, radio access technology (RAT) type, RAN node ID, and UPF ID.

[0201] In step 1, the SMF or other consumer NFs may send a request message for data path prediction information to the NWDAF. The request message may include information about at least one of the following: current UE location, RAT type, RAN node ID, UPF ID, SMF ID, UPF service area, etc.

[0202] According to one embodiment of the present disclosure, when there is an e2e delay requirement, the SMF may request the NWDAF to measure the e2e delay. The SMF may transmit (or forward) to the NWDAF at least one of a request message (e.g., an Nnwdaf_AnalyticsInfo_Request message) or a subscription message (e.g., an Nnwdaf_AnalyticsSubscription_Subscribe message) including network delay information (e.g., Analytics ID = DN Performance, UL / DL Performance data including average / maximum packet delay) to measure the e2e delay that occurs when connecting to a candidate PSA-UPF for each Target DNAI.

[0203] According to one embodiment of the present invention, when there is an N6 delay requirement (e.g., requirement related to N6 data path delay time), the SMF may request N6 delay time related analysis information to the NWDAF. The SMF may send (or forward) at least one of a request message (e.g., an Nnwdaf_AnalyticsInfo_Request message) or a subscription message (e.g., an Nnwdaf_AnalyticsInfo_Request / Nnwdaf_AnalyticsSubscription_Subscribe message) including network delay information (e.g., Analytics ID = Analytics ID = QoS Sustainability, average / maximum N6 delay) to the NWDAF for measuring the N6 delay that occurs when connecting to a candidate PSA-UPF for each Target DNAI.

[0204] When performing a PSA-UPF (re)selection operation based on the N6 delay requirement, the SMF may request predicted delay information on the user plane based on the N3 and N9 segments.

[0205] In step 2a, if e2e delay measurements for each Candidate PSA-UPF associated with the Target DNAI are available, the NWDAF can send (or forward) a subscription message (e.g., a Naf_EventExposure_Subscribe message) to the AF for event subscription. The subscription message can be sent to the AF via the NEF. The subscription message can include information such as Event ID=Performance Data, UL / DL Performance data including average / maximum packet delay, etc.

[0206] When e2e delay is measured for each Candidate PSA-UPF associated with Target DNAIs, AF can send (or forward) delay information (e.g., average and / or maximum packet delay for an application information) to NWDAF via a notification message (e.g., Naf_EventExposure_Notify message).

[0207] In step 2b, the NWDAF can send (or forward) to the UPF via an event subscription message (e.g., Nupf_EventExposure_Subscribe message) to request N6 delay and user plane delay measurements for each Candidate PSA-UPF associated with the Target DNAIs. The event subscription message can include information such as Event ID = QoS Monitoring, QoS flow Packet Delay, UL / DL N6 delay, etc.

[0208] When the N6 delay per Candidate PSA-UPF connected to the Target DNAIs is measured, the UPF may send (or forward) to the NWDAF via a notification message (e.g., a Nupf_EventExposure_Notify message) at least one of the average / maximum N6 delay for an application or user plane delay information between the Candidate PSA-UPF and the terminal.

[0209] In step 2c, the NWDAF may analyze (or measure or calculate) at least one of N6 or user plane delay information or e2e delay information based on requirement information received or transmitted from the SMF. The N6 or user plane delay information may be analyzed by calculating an average of N6 delay information measured over a period of time based on information of a Candidate PSA-UPF associated with a specific DNAI, or may be analyzed (or measured or calculated) based on the maximum N6 or user plane delay information generated over a period of time of a specific Candidate PSA-UPF.

[0210] In step 3, NWADF can forward the analyzed N6 or user plane latency information to SMF via Nnwdaf_AnalyticsInfo_Request Response or Nnwdaf_AnalyticsSubscription_Notify message. The message can include information about estimated DN performance including at least one of estimated DN performance N6 delay, UP delay (UPF), or e2e latency (AF).

[0211] In step 4, the SMF may perform EAS (re)selection or transmit (or forward) N6 delay information to the EASDF for (re)selection based on the N6 or user plane delay information received from the NWDAF.

[0212] FIG. 7a and FIG. 7b are diagrams illustrating an EAS (re)selection decision procedure considering data path delay according to one embodiment of the present disclosure.

[0213] In step 1, the UE can send (or forward) a PDU session establishment request message (e.g., a PDU session establishment procedure message) to the SMF. The SMF can determine whether the UE can find EAS information using the EASDF based on the UE's subscription information (e.g., subscription information) received from the UDM.

[0214] In step 2, the SMF can select the EASDF. Based on the UE's subscription information, the SMF can select the EASDF as the DNS server associated with the PDU session. The SMF can instruct the UE whether to allow the use of the Edge DNS Client (EDC) function or whether the EDC function is required for the PDU session. The SMF can configure the information between the EASDF and the DNS server in the DN to be forwarded through the PSA UPF, depending on the network operator's local settings. The SMF can configure the PSA UPF to forward DNS messages between the EASDF and the DN by forwarding N4 rules.

[0215] In step 3, if the SMF receives predicted N6 latency information during NWDAF or UPF selection, the SMF may decide to forward at least one of the EAS selection indicator information based on the N6 latency or the N6 latency information of the predicted EASs to the EASDF to perform EAS selection in the EASDF. If the SMF does not receive predicted N6 latency information, the SMF may forward the EAS selection indicator information to the EASDF. The predicted N6 latency information may be about EASs and may be based on EAS deployment information or AF requirements. In addition, the N6 latency information may be for EAS selection. In addition, the N6 latency information may be predicted based on EASDF and PSA information.

[0216] In step 4, the SMF may send (or forward) a request message (e.g., a Neasdf_DNSContext_Create Request message) to the selected EASDF. The request message may include a UE IP address, a subscription permanent identifier (SUPI), a DNN, a notification endpoint, DNS message handling rules, etc. The EASDF may create a DNS context related to the PDU session and store at least one of the UE IP address, the SUPI, or the notification endpoint. The DNS message handling rules may be set to the EASDF before a DNS query message is received by the EASDF or as a result of a DNS query report. The SMF may include an EAS selection action indicator (e.g., EAS selection information or EAS selection indication) that takes N6 latency into account and N6 latency requirement information in the DNS message handling rule (e.g., DNS message handling rule) and send (or forward) the DNS message handling rule to the EASDF according to the policies of network operators and service providers. Here, the N6 delay requirement information may include information about the measured N6 delay for the EAS IP range.

[0217] The SMF may send (or forward) the EAS selection action indicator and N6 delay requirement information based on the N6 delay to the EASDF via a BaselineDNSPattern message (e.g., Neasdf_BaselineDNSPattern_Create and / or Update and / or Delete message) according to the policies of the network operator and service provider. If the SMF separately forwards the EAS selection action indicator and N6 delay requirement information considering the N6 delay to the EASDF via the BaselineDNSPattern service operation, the SMF may not include at least one of the separate N6 delay requirement information or the EAS selection action indicator information in the Neasdf_DNSContext_Create Request message.

[0218] In step 5, EASDF can send (or forward) a response message (e.g., a Neasdf_DNSContext_Create Response message) to SMF. The response message allows EASDF to inform SMF that a DNS context has been successfully created within EASDF.

[0219] The PDU session establishment permission message may include the IP address information of the EASDF. The terminal may set the EASDF as the DNS server address for the PDU session.

[0220] The procedure for creating a DNS context (e.g., DNS context creation procedure) may include at least one of steps 1, 2, 3, 4, or 5 above.

[0221] In step 6, the SMF may send (or forward) an update request message (e.g., a Neasdf_DNSContext_Update Request message) to the EASDF. The update request message may include an EASDF Context ID, DNS message processing rules, etc. The update may be triggered by UE mobility. For example, an update may be triggered by at least one of insertion and / or removal of a local PSA, such as when the UE moves to a new location, when the EASDF reports a DNS query containing a specific fully qualified domain name (FQDN), or when updating rules for processing DNS messages from the UE, or when updating with new policy and charging control rule (PCC) rule information.

[0222] In step 7, EASDF may send (or forward) a response message (e.g., a Neasdf_DNSContext_Update Response message) to SMF. The response message may contain response information for the DNS context update operation.

[0223] A DNS context update procedure (e.g., a DNS context update procedure) may include at least one of step 6 or step 7.

[0224] In step 8, the terminal can send (or forward) a DNS query message (e.g., a DNS Query message) to the EASDF.

[0225] If the DNS query message transmitted by the terminal matches a DNS message detection template within the DNS message processing rules, EASDF may send (or forward) the DNS message ID and DNS message report to SMF via a request message (e.g., Neasdf_DNSContext_Notify Request message) in step 9.

[0226] In step 10, SMF may send (or forward) a response message (e.g., a Neasdf_DNSContext_Notify Response message) to EASDF. SMF may send (or forward) the response message with response information for the DNS message report.

[0227] If the DNS message processing rules related to the FQDN in the DNS message report require an update, the SMF may send (or forward) the updated DNS message processing rules to the EASDF via a request message (e.g., a Neasdf_DNSContext_Update Request message) in step 11. If there is no update, the EASDF may send (or forward) a DNS query message to at least one of the configured DNS servers or resolvers.

[0228] If there is a separate DNS message processing rule update request, EASDF may send (or forward) a response message (e.g., a Neasdf_DNSContext_Update Response message) to SMF in step 12. The response message may include response information for the update.

[0229] If the DNS query message transmitted by the terminal does not match the FQDN information of the DNS message detection template information in the DNS processing rule, the EASDF may send (or forward) the DNS query message (e.g., the DNS query message) to at least one of a preset DNS server or resolver in step 13. For example, the UE may send a DNS query requesting an IP address for an FQDN (Fully Qualified Domain Name) of an EAS to which the UE wishes to connect to the preset DNS server. The DNS server may return to the UE the IP address of the EAS that is closest to the UE among the EASs corresponding to the FQDN. At this time, the DNS server may estimate the location of the UE through at least one of the source IP address of the DNS query or the ECS (EDNS (extension mechanisms for DNS) Client Subnet) option.

[0230] In step 14, EASDF can receive a response message (e.g., a DNS Response message) containing EAS IP address information from the DNS server. EASDF can forward the DNS response to the terminal.

[0231] In step 15, the EASDF may select an EAS based on the EAS address information in the DNS query response message. If the EASDF does not receive the predicted N6 delay values ​​for each EAS, the EASDF may not perform step 15. If the EASDF does not receive the predicted N6 delay values ​​for each EAS, the EASDF may send (or forward) the IP addresses of the EASs in the DNS query response information to the SMF, and receive (or be forwarded) the measured N6 delay values ​​for each EAS from the SMF.

[0232] If the EAS IP address or FQDN information in the DNS response message matches the DNS message detection template, the EASDF can send (or forward) the EAS information to the SMF through DNS message reporting. If there are multiple EAS IP addresses received from the DNS server, the EASDF can include a list of EAS IP addresses in the DNS message reporting. According to the DNS message processing rules, the EASDF may not send (or forward) the DNS response message to the terminal, but may buffer the DNS response. If there is an instruction for reporting or forwarding from the SMF, the EASDF can send (or forward) the DNS response message to the terminal. If the one-time reporting control information is set in the EASDF, the EASDF can report (or report) information about the DNS response matching the DNS message detection template to the SMF only once. An EASDF that has not received the predicted N6 delay time values ​​for each EAS may send (or forward) to the SMF a DNS message reporting including the IP addresses, FQDN information, and DNS message ID of the EASs to request the measured N6 delay time values ​​for each EAS.

[0233] In step 17, the SMF may send (or forward) a response message for DNS response reporting (e.g., a Neasdf_DNSContext_Notify Response message or response reporting) to the EASDF. The response message may include the EAS-specific measured N6 latency value received by the SMF from at least one of the NWDAF or UPF.

[0234] The SMF can check the DNAI information that is mapped to the EAS-related information (e.g., IP address, FQDN information, etc.) in the DNS response reporting based on the information in the EDI (EAS Deployment Information) received or transmitted through AF, etc. The SMF can request the NWDAF to analyze (or measure) the N6 delay time values ​​of the EAS connected to the candidate UPFs by transmitting the request information for N6 delay time measurement including the DNAI information to the NWDAF.

[0235] In step 18, the EASDF can select an EAS based on its N6 latency requirements. The N6 latency requirements can be received or forwarded from the SMF based on measured N6 latency information per EAS IP address.

[0236] In step 19, the SMF may select and / or insert at least one of an uplink classifier (ULCL), a branching point (BP), or a Local PSA. The SMF may receive EAS information from the EASDF via a notification message (e.g., a Neasdf_DNSContext_Notify message). The EASDF may select a DNAI based on Service Experience or DN performance analytics for an Edge Application. The SMF may determine N6 traffic routing information for a DNAI based on N6 traffic routing information for the DNAI included in the EAS deployment information. The SMF may configure a Local PSA UPF including forwarding based on the N6 traffic routing information. Traffic detection rules and traffic routing rules may be determined by the SMF based on at least one of a DNAI-specific IP address range included in the EAS deployment information, a PCC rule received from the PCF, or pre-configured information.

[0237] In step 20, the SMF may transmit a request message (e.g., a Neasdf_DNSContext_Update Request message) to the EASDF. The request message may include DNS message control rule information. The DNS message control rule information may include at least one of the 'Send the buffered DNS response(s) message to UE' control operation information and EAS information selected based on the N6 delay. If the EAS selection operation based on the N6 requirement is performed in the EASDF according to the network or service provider's configuration, separate EAS information may not be included in the message transmitted (or forwarded) from the SMF. The SMF may transmit (or forward) at least one of the DNS message control rule information including the DNS message ID transmitted from the EASDF and the 'Send the buffered DNS response(s) message to UE' control information to the EASDF.

[0238] In step 21, EASDF may send (or forward) a response message (e.g., a Neasdf_DNSContext_Update Response message) to SMF. The response message may include response information related to the DNS message ID.

[0239] In step 22, the EASDF may transmit (or forward) a DNS response message (e.g., a DNS response message) to the terminal. The response message may include IP information of the selected EAS based on the N6 delay.

[0240] FIG. 8 is a diagram illustrating the structure of a terminal according to an embodiment of the present invention.

[0241] Referring to FIG. 8, the terminal may include a transceiver (810), a control unit (820), and a storage unit (830). In the present invention, the control unit may be defined as a circuit or an application-specific integrated circuit or at least one processor.

[0242] The transceiver (810) can transmit and receive signals with other network entities. The transceiver (810) can receive system information from a base station, for example, and can receive synchronization signals or reference signals.

[0243] The control unit (820) can control the overall operation of a terminal according to an embodiment proposed in the present invention. For example, the control unit (820) can control the signal flow between each block so that the terminal transmits a re-INVITE message for application data channel connection to the IMS AS according to an embodiment of the present invention.

[0244] The storage unit (830) can store at least one of the information transmitted and received through the transmission and reception unit (810) and the information generated through the control unit (820). For example, the storage unit (830) can store information for a video or audio session bootstrap data channel connection.

[0245] FIG. 9 is a diagram illustrating a network entity according to one embodiment of the present invention.

[0246] The network entity illustrated in FIG. 9 may be composed of one of various types of network entities disclosed in the present invention, for example, AMF, SMF, PCF, UPF, AUSF, UDM, AF, NSSF, NRF, NEF, NWDAF, etc.

[0247] Referring to FIG. 9, a network entity may include a transceiver (910), a control unit (920), and a storage unit (930). In the present invention, the control unit may be defined as a circuit or an application-specific integrated circuit or at least one processor.

[0248] The transceiver (910) can transmit and receive signals with other network entities. The transceiver (910) can receive, for example, request messages for various information from terminals, base stations, or other network entities.

[0249] The control unit (920) can control the overall operation of a network entity according to an embodiment proposed in the present invention. For example, the control unit (920) can cause a network entity to perform channel establishment-related policy decisions according to an embodiment disclosed in the present invention.

[0250] The storage unit (930) can store at least one of the information transmitted and received through the transmission and reception unit (910) and the information generated through the control unit (920). For example, the storage unit (930) can store information related to media control.

[0251] Meanwhile, the embodiments of the present invention disclosed in this specification and drawings are merely specific examples to easily explain the technical content of the present invention and help understand the present invention, and are not intended to limit the scope of the present invention. In other words, it will be apparent to those skilled in the art that other modifications based on the technical concept of the present invention are possible. In addition, each of the above embodiments can be combined and operated as needed. For example, at least a portion of each of the embodiments of the present invention can be combined and operated by a base station, a terminal, or a specific network entity.

[0252] The methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0253] When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. The one or more programs may include instructions that cause the electronic device to execute methods according to the embodiments described in the claims or specification of the present disclosure.

[0254] These programs (software modules, software) may be stored in a non-volatile memory including random access memory, flash memory, Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), a magnetic disc storage device, a Compact Disc-ROM (CD-ROM), Digital Versatile Discs (DVDs) or other forms of optical storage devices, a magnetic cassette. Or, they may be stored in a memory composed of a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

[0255] Additionally, the program may be stored on an attachable storage device that is accessible via a communication network such as the Internet, an intranet, a local area network (LAN), a wide local area network (WLAN), a storage area network (SAN), or a combination thereof. Such a storage device may be connected to a device performing an embodiment of the present disclosure via an external port. Additionally, a separate storage device on the communication network may be connected to a device performing an embodiment of the present disclosure.

[0256] In the specific embodiments of the present disclosure described above, components included in the present disclosure are expressed in the singular or plural form, depending on the specific embodiment presented. However, the singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components. Components expressed in the plural form may be composed of singular elements, or components expressed in the singular form may be composed of plural elements.

[0257] It should be noted that the configuration diagrams, example diagrams of control / data signal transmission methods, example diagrams of operating procedures, and configuration diagrams illustrated in the above FIGS. 1 to 9 are not intended to limit the scope of the present disclosure. That is, not all components, entities, or operational steps described in the above FIGS. 1 to 8 should be construed as essential components for implementing the disclosure, and the disclosure may be implemented without detriment to its essence even if only some components are included.

[0258] The operations of the network entity or terminal described above can be realized by providing a memory device storing the corresponding program code within any component of the network entity or terminal device. That is, the control unit of the network entity or terminal device can execute the operations described above by reading and executing the program code stored in the memory device using a processor or CPU (Central Processing Unit).

[0259] The various components and modules of the network entity, base station or terminal device described in this specification may be operated using hardware circuits, such as logic circuits based on complementary metal oxide semiconductors, firmware, software and / or hardware and firmware and / or software embedded in a machine-readable medium. For example, various electrical structures and methods may be implemented using electrical circuits such as transistors, logic gates and application-specific semiconductors.

[0260] While the detailed description of the 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 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 communication system, the method comprising: A step of receiving a notify message from a policy control function (PCF) entity, the notification message including a policy and charging control (PCC) rule for measurement of N6 delay, wherein the measurement of N6 delay is a measurement of a connection between at least one user plane function (UPF) entity and a measurement endpoint of a data network (DN); A step of receiving edge application server deployment information (EDI) for the measurement of the N6 delay from an application function (AF) entity; and A method characterized by comprising the step of transmitting a request message for the measurement of the N6 delay to at least one UPF entity.

2. In paragraph 1, In response to the request message, receiving a report message from the at least one UPF entity, the report message including the result of the measurement for the N6 delay; and A method characterized in that it further comprises the step of selecting any one of the at least one UPF entity based on the result of the above measurement.

3. In paragraph 2, A method characterized in that it further comprises a step of re-exploring EAS based on the above results of the above measurement.

4. In paragraph 1, The above measurement for the N6 delay is performed based on at least one of a measurement protocol or a reporting cycle, The measurement protocol comprises at least one of a two-way active measurement protocol (TWAMP), a one-way active measurement protocol (OWAMP), or a simple two-way active measurement protocol (STAMP), and A method characterized in that the EDI is related to at least one of domain name system (DNS) server information, EAS internet protocol (IP) information, fully qualified domain name (FQDN) information, or data network access identifier (DNAI) information.

5. A method performed by a user plane function (UPF) entity in a communication system, the method comprising: A step of receiving a request message for measurement of N6 delay from a session management function (SMF) entity, wherein the measurement of N6 delay is a measurement of a connection between at least one UPF entity and a measurement endpoint of a data network (DN), A step of performing the measurement for the N6 delay based on the request message; and In response to the request message, the step of transmitting a report message including the result of the measurement for the N6 delay to the SMF entity; A method characterized in that the measurement for the N6 delay is related to a notify message including a policy and charging control (PCC) rule received from a policy control function (PCF) entity and edge application server (EAS) deployment information (EDI) received from an application function (AF) entity.

6. In paragraph 5, A method characterized in that, based on the above results for the above measurement, any one of the at least one UPF entity is selected.

7. In paragraph 6, A method characterized in that the EAS is re-explored based on the above results for the above measurement.

8. In paragraph 5, The above measurement for the N6 delay is performed based on at least one of a measurement protocol or a reporting cycle, The measurement protocol comprises at least one of a two-way active measurement protocol (TWAMP), a one-way active measurement protocol (OWAMP), or a simple two-way active measurement protocol (STAMP), and A method characterized in that the EDI is related to at least one of domain name system (DNS) server information, EAS internet protocol (IP) information, fully qualified domain name (FQDN) information, or data network access identifier (DNAI) information.

9. In a session management function (SMF) entity in a communication system, the SMF entity: Transmitter and receiver; and A control unit coupled to the above transmitter and receiver, wherein the control unit: Receive a notify message from a policy control function (PCF) entity, which includes a policy and charging control (PCC) rule for measurement of N6 delay, wherein the measurement of N6 delay is a measurement for a connection between at least one user plane function (UPF) entity and a measurement endpoint of a data network (DN), Receive edge application server deployment information (EDI) for the measurement of the N6 delay from an application function (AF) entity, and An SMF entity characterized in that it transmits a request message for the measurement of the N6 delay to at least one UPF entity.

10. In paragraph 9, the control unit: In response to the request message, receiving a report message from the at least one UPF entity, the report message including the result of the measurement for the N6 delay, and An SMF entity characterized in that, based on the above results for the above measurement, any one of the at least one UPF entity is selected.

11. In paragraph 10, the control unit: An SMF entity characterized in that it re-explores EAS based on the above results for the above measurement.

12. In paragraph 9, The above measurement for the N6 delay is performed based on at least one of a measurement protocol or a reporting cycle, The measurement protocol comprises at least one of a two-way active measurement protocol (TWAMP), a one-way active measurement protocol (OWAMP), or a simple two-way active measurement protocol (STAMP), and An SMF entity characterized in that the EDI is related to at least one of domain name system (DNS) server information, EAS internet protocol (IP) information, fully qualified domain name (FQDN) information, or data network access identifier (DNAI) information.

13. In a user plane function (UPF) entity in a communication system, the UPF entity: Transmitter and receiver; and A control unit coupled to the above transmitter and receiver, wherein the control unit: Receive a request message for measurement of N6 delay from a session management function (SMF) entity, wherein the measurement of N6 delay is a measurement of a connection between at least one UPF entity and a measurement endpoint of a data network (DN), Performing the measurement for the N6 delay based on the above request message, and In response to the above request message, send a report message to the SMF entity including the result of the measurement for the N6 delay, A UPF entity characterized in that the measurement for the N6 delay is related to a notify message including a policy and charging control (PCC) rule received from a policy control function (PCF) entity and edge application server (EAS) deployment information (EDI) received from an application function (AF) entity.

14. In paragraph 13, Based on the above results for the above measurement, any one of the at least one UPF entity is selected, and A UPF entity characterized in that the EAS is re-explored based on the above results for the above measurement.

15. In paragraph 13, The above measurement for the N6 delay is performed based on at least one of a measurement protocol or a reporting cycle, The measurement protocol comprises at least one of a two-way active measurement protocol (TWAMP), a one-way active measurement protocol (OWAMP), or a simple two-way active measurement protocol (STAMP), and A UPF entity characterized in that the EDI is related to at least one of domain name system (DNS) server information, EAS internet protocol (IP) information, fully qualified domain name (FQDN) information, or data network access identifier (DNAI) information.

Images