Method and device for user data session setup taking user service into account

Abstract

The present invention relates to a 5G or 6G communication system for supporting a higher data transmission rate. A method for a session management function (SMF) operating in a wireless communication system, according to one embodiment of the present invention, may comprise the steps of: receiving a protocol data unit (PDU) session generation request message from an access and mobility management function (AMF); acquiring session management subscription data of a terminal from unified data management (UDM) on the basis of the PDU session generation request message; and determining a UPF for a PDU session to be generated, on the basis of the session management subscription data.

Description

Method and device for establishing a user data session considering user service

[0001] The present disclosure relates to terminal and network operations in a wireless communication system. More specifically, the present disclosure relates to a method and device for establishing a data session for user data transmission in a wireless communication system while taking user services into consideration.

[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 (THz) band (for example, 3 THz 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] Based on the discussion described above, the present disclosure aims to provide a method and device for establishing a data session capable of efficiently transmitting user data (service data flow) to a network by taking user data into consideration when establishing a data session in a wireless communication system.

[0009] 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.

[0010] According to one embodiment of the present invention, a method for operating a session management function (SMF) in a wireless communication system may include the steps of: receiving a PDU (protocol data unit) session creation request message from an AMF (access and mobility management function); obtaining session management subscription data of a terminal from a UDM (unified data management) based on the PDU session creation request message; and determining a user plane function (UPF) for a PDU session to be created based on the session management subscription data.

[0011] The above session management subscription data may include information about a PSA (PDU session anchor) UPF function, and the information about the UPF function may include information about a preferred PSA UPF function for the PDU session.

[0012] The above SMF method may further include a step of transmitting information about a UPF function to be applied to the PDU session with the determined UPF.

[0013] The method of the above SMF may further include a step of receiving a policy and charging control (PCC) rule for establishing the PDU session from a policy control function (PCF), and the UPF decision for the PDU session to be created is determined additionally based on the PCC rule, and the PCC rule may include information on a PSA UPF function.

[0014] According to one embodiment of the present invention, a method for operating a policy control function (PCF) in a wireless communication system may include the steps of: receiving a request message for generating a session management (SM) policy from a session management function (SMF); generating a policy and charging control (PCC) rule based on the request message; and transmitting the generated PCC rule to the SMF.

[0015] The above PCF method may further include a step of obtaining subscription-related information of a terminal from a united data repository (UDR), and the generation of the PCC rule may be additionally generated based on the subscription-related information.

[0016] The method of the above PCF may further include a step of obtaining data related to the terminal's data usage from a CHF (charging function), and the generation of the PCC rule may be additionally generated based on the data related to the data usage.

[0017] One embodiment of the present invention provides a device and method capable of effectively providing a service in a wireless communication system.

[0018] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0019] FIG. 1 illustrates the structure of a wireless communication system according to various embodiments of the present disclosure.

[0020] FIG. 2 illustrates a UPF according to one embodiment of the present disclosure.

[0021] FIG. 3 illustrates a deployment scenario of a Modular UPF and a conventional UPF according to one embodiment of the present disclosure.

[0022] FIG. 4a and FIG. 4b are diagrams illustrating a PDU session creation procedure according to one embodiment of the present disclosure.

[0023] Figure 5 illustrates the SM Policy Association creation procedure for a PDU Session between an SMF and a PCF.

[0024] Figure 6 illustrates the configuration of a terminal according to embodiments of the present disclosure.

[0025] FIG. 7 illustrates a configuration of a base station or network entity according to embodiments of the present disclosure.

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. It should be noted that, where possible, identical components are represented by identical reference numerals throughout the drawings. Furthermore, detailed descriptions of well-known functions and configurations that may obscure the gist of the present invention will be omitted.

[0027] In describing the embodiments herein, descriptions of technical details that are well known in the technical field to which the present disclosure pertains and are not directly related to the present invention will be omitted. This is to avoid obscuring the gist of the present disclosure by omitting unnecessary explanations and to convey the gist more clearly.

[0028] 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.

[0029] The advantages and features of the present disclosure, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below 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 only to ensure that the disclosure of 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 refer to like elements throughout the specification.

[0030] Furthermore, when describing the present disclosure, detailed descriptions of related functions or configurations will be omitted if they are deemed to unnecessarily obscure the gist of the present disclosure. Furthermore, the terms described below are defined based on the functions of the present disclosure and may vary depending on the intent or custom of the user or operator. Therefore, their definitions should be based on the content throughout this specification.

[0031] Hereinafter, the base station is an entity that performs resource allocation of the terminal, and may be at least one of a gNode B (gNB), an eNode B (eNB), a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, downlink (DL) refers to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, in the following, LTE (long-term evolution), LTE-A (LTE-advanced) or 5G (5 thAlthough the present disclosure may be described as an example of a 5G (new radio (NR)) system, the embodiments of the present disclosure may also be applied to other communication systems with similar technical backgrounds or channel types. For example, the 5G (new radio (NR)) mobile communication technology developed after LTE-A may be included here, and the 5G below may be a concept that includes 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.

[0032] At this time, it will be understood that each block of the processing flow diagrams and combinations of the flow diagrams 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 flow diagram 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 flow diagram 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).

[0033] 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.

[0034] Here, the term '~ unit' used in the present embodiments means a software or hardware component such as an FPGA or ASIC, and the '~ unit' performs certain roles. However, the '~ unit' is not limited to software or hardware. The '~ unit' may be configured to be on an addressable storage medium and may be configured to reproduce one or more processors. Thus, as an example, the '~ unit' 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 '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, the components and '~ units' may be implemented to reproduce one or more CPUs within a device or a secure multimedia card. Additionally, in the embodiment, '~bu' may include one or more processors.

[0035] Wireless communication systems have evolved from providing voice-oriented services in the early days to broadband wireless communication systems that provide high-speed, high-quality packet data services, such as communication standards such as 3GPP's HSPA (High Speed ​​Packet Access), LTE (or E-UTRA (Evolved Universal Terrestrial Radio Access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's HRPD (High Rate Packet Data), UMB (Ultra Mobile Broadband), and IEEE's 802.16e.

[0036] As a representative example of a broadband wireless communication system, the LTE system uses the OFDM (Orthogonal Frequency Division Multiplexing) method in the downlink and the SC-FDMA (Single Carrier Frequency Division Multiple Access) method in the uplink. The uplink refers to a wireless link in which a terminal (User Equipment (UE) or Mobile Station (MS)) transmits data or control signals to a base station (eNode B, gNode B, or base station (BS)), and the downlink refers to a wireless link in which a base station transmits data or control signals to a terminal. The above-described multiple access method can distinguish the data or control information of each user by allocating and operating the time-frequency resources to be transmitted, including data or control information, so that they do not overlap with each other (i.e., so that orthogonality is established).

[0037] As a future communication system beyond LTE, 5G communication systems must be able to freely reflect the diverse needs of users and service providers. Therefore, they must support services that simultaneously satisfy these diverse requirements. Services being considered for 5G communication systems include enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra-Reliable Low Latency Communication (URLLC).

[0038] eMBB aims to provide data transmission rates that are significantly higher than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to support a peak data rate of 20 Gbps in the downlink and a peak data rate of 10 Gbps in the uplink from a single base station. Furthermore, 5G communication systems must simultaneously provide the peak data rate and an increased user-perceived data rate for terminals. To meet these requirements, improvements in various transmission and reception technologies, including improved multi-input, multi-output (MIMO) transmission technology, are required. Furthermore, while LTE transmits signals using a maximum 20 MHz transmission bandwidth in the 2 GHz band, 5G communication systems can meet the data transmission rates required by 5G communication systems by utilizing a wider frequency bandwidth than 20 MHz in the 3-6 GHz or higher 6 GHz bands.

[0039] At the same time, massive Machine Type Communications (mMTC) is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. To efficiently provide the IoT, mMTC requires supporting a large number of terminals within a cell, improving terminal coverage, extending battery life, and reducing terminal costs. The IoT requires the ability to support a large number of terminals (e.g., 1,000,000 terminals / km^2) within a cell, as it provides communication capabilities through the attachment of various sensors and devices. Furthermore, terminals supporting mMTC are likely to be located in shadow areas, such as basements, beyond cell coverage due to the nature of the service, and thus may require wider coverage than other services provided by 5G communication systems. Terminals supporting mMTC must be inexpensive, and because frequent battery replacement is difficult, they may require extremely long battery lifespans, such as 10 to 15 years.

[0040] Finally, URLLC refers to a cellular-based wireless communication service used for a specific purpose (mission-critical). Examples include remote control of robots or machinery, industrial automation, unmanned aerial vehicles (UAVs), remote health care, and emergency alerts. Therefore, URLLC communications must provide extremely low latency and high reliability. For example, services supporting URLLC must meet air interface latency requirements of less than 0.5 milliseconds and a packet error rate (PER) of less than 10^-5. Therefore, for services supporting URLLC, 5G systems must provide a shorter transmission time interval (TTI) than other services, and design requirements may require the allocation of extensive resources in the frequency band to ensure communication link reliability.

[0041] The three 5G services—eMBB, URLLC, and mMTC—can be multiplexed and transmitted within a single system. To meet the differing requirements of each service, different transmission and reception techniques and parameters can be used. Of course, 5G is not limited to the three services described above.

[0042] According to various embodiments of the present disclosure, phrases such as “A and / or B,” “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B, or C,” “at least one of A, B, and C,” and “at least one of A, B, or C” can each include any one of the items listed together in that phrase, or all possible combinations thereof. Terms such as “first,” “second,” or “first” or “second” may be used merely to distinguish the corresponding element from other corresponding elements and do not limit the corresponding elements in any other respect (e.g., importance or order).

[0043] Hereinafter, the base station is an entity that performs resource allocation of a terminal, and may be at least one of a Node B, a BS (Base Station), an eNB (eNode B), a gNB (gNode B), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In addition, the embodiments of the present disclosure may be applied to other communication systems having a similar technical background or channel form to the embodiments of the present disclosure described below. In addition, the embodiments of the present disclosure may be applied to other communication systems through some modifications without significantly departing from the scope of the present disclosure at the discretion of a person having skilled technical knowledge.

[0044] In the present disclosure, network technology may refer to standard specifications defined by the International Telecommunication Union (ITU) or 3GPP (e.g., TS 23.501, TS 23.502, TS 23.503, etc.), and components included in the network structure of FIG. 1 may each mean a physical entity, or may mean software performing an individual function, or hardware combined with software. Reference symbols shown as Nx, such as N1, N2, N3, ..., in the drawings represent known interfaces between NFs (network functions) in a 5G core network (CN), and since a related description may refer to a standard specification (e.g., TS 23.501), a detailed description will be omitted.

[0045] In the following description, terms used to identify connection nodes, terms referring to network entities (NEs) or network functions (NFs), terms referring to messages, terms referring to interfaces between network objects, terms referring to various identification information, etc. are examples provided 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.

[0046] For convenience of explanation, some terms and names defined in the 3rd generation partnership project long-term evolution (3GPP) standards may be used. However, the present disclosure is not limited to these terms and names, and can be equally applied to systems conforming to other standards.

[0047] FIG. 1 illustrates the architecture of a wireless communication system according to various embodiments of the present disclosure. More specifically, FIG. 1 illustrates an example of the configuration of a 5G system. Referring to FIG. 1, a 5G network may include at least one of the following network entities (NEs) or network functions (NFs).

[0048] According to one embodiment, the (R)AN ((Radio) Access Network) is an entity that performs radio resource allocation of a terminal, and may include at least one of an eNode B, a Node B, a BS (Base Station), an NG-RAN (Next Generation Radio Access Network), a 5G-AN (5G Access Network), a 5G NR (5G New Radio), a radio access unit, a base station controller, or a node on a network.

[0049] According to one embodiment, the terminal may include a User Equipment (UE), a Next Generation UE (NG UE), a Mobile Station (MS), a cellular phone, a smartphone, a computer, an Internet of Things (IoT) device, or a multimedia system capable of performing a communication function.

[0050] Furthermore, while the embodiments of the present disclosure are described below using a 5G system as an example, the embodiments of the present disclosure can also be applied to other communication systems with similar technical backgrounds. Furthermore, the embodiments of the present disclosure can be applied to other communication systems with some modifications, as determined by a person skilled in the art, without significantly departing from the scope of the present disclosure.

[0051] As wireless communication systems evolve from 4G to 5G, a new core network (CN) called the Next Generation Core (NG Core) or 5GC (5G Core Network) is defined. This new core network can virtualize all existing network entities (NEs) into network functions (NFs). According to one embodiment of the present disclosure, a network function may refer to a network entity, a network component, or a network resource.

[0052] According to one embodiment of the present disclosure, 5GC may include one or more NFs illustrated in FIG. 1. Of course, the present invention is not limited to the example illustrated in FIG. 1, and 5GC may include more or fewer NFs than the NFs illustrated in FIG. 1.

[0053] In one embodiment, the Access and Mobility Management Function (AMF) may be a network function that manages access and mobility of a terminal (UE). For example, the AMF may perform network functions such as terminal registration, connection, reachability, mobility management, access verification, authentication, and mobility event generation.

[0054] In one embodiment, a Session Management Function (SMF) may be a network function that manages a Packet Data Network (PDN) connection provided to a User Equipment (UE). The PDN connection may be referred to as a Protocol Data Unit (PDU) Session. For example, the SMF may perform network functions such as session management through establishing, modifying, and releasing sessions and maintaining tunnels between a User Plane Function (UPF) and the RAN, selecting and controlling a User Plane (UPF), controlling traffic processing in the UPF, and controlling the collection of charging data.

[0055] In one embodiment, the Policy Control Function (PCF) may be a network function that applies a mobile communication operator's service policy, charging policy, and policy for PDU Session to a terminal.

[0056] In one embodiment, Unified Data Management (UDM) may be a network function that stores subscriber information. For example, UDM may perform functions such as generating authentication information for 3GPP security, processing user identifiers (User IDs), managing a list of network functions supporting UEs, and managing subscription information.

[0057] In one embodiment, the Network Exposure Function (NEF) may provide information about a terminal to a server outside the 5G network. Furthermore, NEF may provide the ability to provide information necessary for 5G network services and store it in the Unified Data Repository (UDR).

[0058] In one embodiment, the User Plane Function (UPF) may be a function that acts as a gateway to transmit user data (e.g., PDU) to the Data Network (DN). More specifically, the UPF may perform a data processing function so that data transmitted by a terminal can be transmitted to an external network or data received from an external network can be transmitted to the terminal. For example, the UPF may perform network functions such as serving as an anchor between Radio Access Technologies (RATs), packet routing and forwarding, packet inspection, user plane policy application, traffic usage report generation, and buffering.

[0059] In one embodiment, the Network Repository Function (NRF) may store profiles of NFs and perform discovery of NFs.

[0060] In one embodiment, the Authentication Server Function (AUSF) can perform terminal authentication in a 3GPP access network and a non-3GPP access network.

[0061] According to one embodiment, the Network Slice Selection Function (NSSF) may perform a function of selecting a Network Slice Instance provided to a terminal.

[0062] In one embodiment, the Network Data Analytics Function (NWDAF) may collect data from multiple NFs (NFs) for the purpose of efficiently operating the 5GC network. In one embodiment, the collected data may be analyzed using a machine learning (ML) model, and the analyzed results may be provided back to the NFs to help each NF provide efficient network services.

[0063] In one embodiment, an Application Function (AF) can communicate with a network operator so that an external server (Application Server) can utilize network services provided by the network operator. Depending on the deployment entity, an AF can be classified as an internal AF or an external AF. An internal AF deployed by a network operator can communicate directly with network function providers (NFs) within the network operator. An AF deployed by a third-party service provider (3rd-party service provider) may need to go through an NEF to communicate with NFs within the network operator.

[0064] In one embodiment, the DN (Data Network) may be a data network through which a terminal transmits and receives data in order to use a network operator's service or a third-party service.

[0065] In one embodiment, the Network Slice Admission Control Function (NSACF) may limit the number of PDU sessions of registered terminals in each slice, thereby performing a resource management function.

[0066] In one embodiment, the Network Slice-Specific Authentication and Authorization Function (NSSAAF) may create a slice authentication context for a terminal and perform slice-specific authentication and authorization procedures.

[0067] In one embodiment, the Edge Application Server Discovery Function (EASDF) may create a domain name system (DNS) context for a PDU session and may perform functions such as storing a UE IP (internet protocol) address, DNS message processing rules, etc. in the context.

[0068] In one embodiment, a Service Communication Proxy (SCP) may perform indirect communication functions such as service discovery, call response, etc.

[0069] In one embodiment, the terminal may include an IoT device. The IoT device may include a device that does not use battery power or operates with very little power, and such an IoT device may be referred to as an ambient IoT device (or Ambient IoT).

[0070] In the 3GPP system, a conceptual link connecting NFs within a 5G system is defined as a reference point. The following illustrates a reference point included in the 5G system architecture depicted in Figure 1.

[0071] - N1: Reference point between UE and AMF

[0072] - N2: Reference point between (R)AN and AMF

[0073] - N3: Reference point between (R)AN and UPF

[0074] - N4: Reference point between SMF and UPF

[0075] - N6: Reference point between UPF and DN

[0076] - N9: Reference point between two core UPFs

[0077] Additionally, in 3GPP systems, the 5G system architecture may include service-based interfaces such as the following examples.

[0078] - Nnssf: Service-based interface by NSSF

[0079] - Nnssaaf: Service-based interface by NSSAAF (Network Slice-Specific Authentication and Authorization Function)

[0080] - Nnef: Service-based interface by NEF

[0081] - Nausf: Service-based interface by AUSF

[0082] - Nnrf: Service-based interface by NRF

[0083] - Namf: Service-based interface by AMF

[0084] - Npcf: Service-based interface by PCF

[0085] - Nsmf: Service-based interface by SMF

[0086] - Nupf: Service-based interface by UPF

[0087] - Nudm: Service-based interface by UDM

[0088] - Naf: Service-based interface by AF

[0089] - Nasaf: Service-based interface by AUSF

[0090] - Neasdf: Service-based interface by EASDF (Edge Application Server Discovery Function)

[0091] - Nnwdaf: Service-based interface by NWDAF

[0092] According to one embodiment of the present disclosure, a UPF module may be composed of multiple modules and functions according to a modular design. According to one embodiment of the present disclosure, when a new service data flow (Service Data Flow or IP Flow) is created, a terminal may transmit the data using an existing created PDU Session to transmit the data to a network, or may transmit the data by creating a new PDU Session. In the present disclosure, a method is proposed for selecting a UPF including a module or function that can efficiently transmit the service data flow when creating a new PDU Session to transmit a new service data flow to a network.

[0093] FIG. 2 illustrates a UPF according to one embodiment of the present disclosure.

[0094] The services provided by UPF can be divided into mandatory functionality and optional functionality. Mandatory functionality includes at least one function essential for the services UPF must provide, while optional functionality may include at least one function necessary to provide additional services beyond the essential functionality of UPF.

[0095] Mandatory functionality provided by UPF may include at least one of a data storage module, a data processing module, a packet processing module, a packet buffer module, a policy rule enforcement module, a traffic usage reporting module, a traffic verification module, and a quality of service (QoS) handling module.

[0096] Optional functionality provided by UPF may include at least one of a network address translation (NAT) module for network address translation, a domain name system (DNS) snooping module, a firewall module, a traffic optimization module, a shallow packet inspection (SPI) module, and a deep packet inspection (DPI) module.

[0097] Depending on the module design, essential functions may not be modularized and only additional functions may be modularized.

[0098] Referring to FIG. 2, a UPF in which at least some functions are modularized according to a module design may be referred to as a modular UPF in order to distinguish it from a conventional non-modular UPF.

[0099] For example, the UPF may include a packet processing module to receive user packets from a data network and transmit them to a terminal, and to receive user packets from a terminal and transmit them to the data network.

[0100] For example, the UPF may include an SPI module (shallow packet inspection) and / or a DPI module (deep packet inspection) for examining user packets received from a terminal or data network. However, the SPI module (shallow packet inspection) and the DPI module (deep packet inspection) may not be services / functions that the UPF must necessarily provide.

[0101] Modularizing UPF by function allows for the expansion and reduction of resources for each module, thereby increasing the flexibility of UPF resource provision. Furthermore, modularizing UPF by function allows for the addition and / or deletion of non-essential features to UPF at any time as needed, potentially resulting in cost savings compared to conventional, fully-functional UPFs.

[0102] FIG. 3 illustrates a deployment scenario of a Modular UPF and a conventional UPF according to one embodiment of the present disclosure.

[0103] Referring to FIG. 3, in a scenario based on the existing UPF, all service data flows are processed by the same UPF regardless of the type of service data flow used by the terminal. However, in a scenario based on the Modular UPF, a Modular UPF that will handle the service data flow can be selected based on the type of service data flow used by the terminal, taking into account the additional functions of the UPF. In one embodiment, in the case of a service data flow for a banking service, a Modular UPF that provides an additional firewall function can be selected because security is important. In one embodiment, in the case of a service data flow for a video streaming service, a Modular UPF that provides an additional caching function for packet latency that can cause buffering is important.

[0104] FIG. 4a and FIG. 4b are diagrams illustrating a PDU session creation procedure according to one embodiment of the present disclosure.

[0105] In Step 1, the UE can request the SMF to establish a PDU session via the AMF. More specifically, when a new service data flow occurs and a suitable PDU session to transmit the flow has not been created, the UE can perform a new PDU session creation procedure. To this end, the UE can transmit a PDU Session Establishment Request message to the AMF. The PDU Session Establishment Request message transmitted by the UE can also be forwarded to the SMF via the AMF.

[0106] According to one embodiment, a NAS message including a PDU Session Establishment Request message may include at least one of the following: S-NSSAI(s), [Alternative S-NSSAI], UE Requested DNN, PDU Session ID, Request type, Old PDU Session ID.

[0107] According to one embodiment, a PDU Session Establishment Request message transmitted to an SMF may include at least one of the following information: a PDU Session ID, a Requested PDU Session Type, a Requested SSC mode, a 5GSM Capability, a Protocol Configuration Option (PCO), a SM PDU DN Request Container, a Number Of Packet Filters, a Header Compression Configuration, a UE Integrity Protection Maximum Data Rate, an Always-On PDU Session Requested, a Redundancy Sequence Number (RSN), Connection Capabilities, and a PDU Session Pair ID.

[0108] In step 2, the AMF can select an SMF. More specifically, the AMF can receive a PDU session establishment request message and select an appropriate SMF accordingly.

[0109] According to one embodiment, the AMF may consider at least one of the following information to select an SMF: DNN, S-NSSAI, Access Technology, Support for CP CIoT 5GS Optimization, Subscription Information from UDM, Local Operator Policies, Load Conditions of Candidates SMF, UE Location, Service Area of ​​SMFs, Target DNAI, etc.

[0110] In step 3, AMF can send an Nsmf_PDUSession_CreateSMContext Request message to the selected SMF.

[0111] According to one embodiment, a message transmitted by AMF may include at least one of the following information:SUPI, Selected DNN, UE Requested DNN, S-NSSAI(s), PDU Session ID, AMF ID, Request Type, [PCF ID, Same PCF Selection Indication], Priority Access, Small Data Rate Control Status, N1 SM Container (PDU Session Establishment Request), User Location Information, Access Type, RAT Type, Permanent Equipment Identifier (PEI), Generic Public Subscription Identifier (GPSI), UE Presence in LADN Service Area (LADN), Subscription For PDU Session Status Notification, DNN Selection Mode, Trace Requirements, Control Plane CIoT 5GS Optimization Indication, Control Plane Only Control Plane Only Indicator, Satellite Backhaul Category, Geostationary Orbit (GEO) Satellite ID, [PVS FQDN(s) and / or PVS IP address(es), Onboarding Indication], Disaster Roaming Service Indication.;

[0112] In step 4, if the subscriber information corresponding to the requested SUPI, DNN, and S-NSSAI does not exist in the SMF, the SMF may request the UE's session management subscription data by sending a Nudm_SDM_Get message to the UDM. The message sent by the SMF may include at least one of the following information: SUPI, session management subscription data, selected DNN, S-NSSAI of the HPLMN, Serving PLMN ID, and NID (Network Identifier).

[0113] Session management subscription data received by SMF from UDM may include the following values: GPSI List, Internal Group ID-list, Trace Requirements, and Routing Indicator. Data at each S-NSSAI level may include: S-NSSAI, Subscribed DNN list, Slice Usage Policy information, and ODB for Packet services.S-NSSAI 별 각 DNN level 의 데이터는 다음을 포함 할 수 있다;DNN, Aerial service indication, Framed Route information, IP Index information, Allowed PDU Session Types, Default PDU Session Type, Allowed SSC modes, Default SSC mode, Interworking with EPS indication, 5GS Subscribed QoS profile, Charging Characteristics, Subscribed-Session-AMBR, Static IP address / prefix, User Plane Security Policy, PDU Session continuity at inter RAT mobility, NEF Identity for NIDD, NIDD information, SMF-Associated Expected UE Behaviour parameters, SMF-Associated Application-Specific Expected UE Behaviours parameters, Suggested number of downlink packets, ATSSS information, Secondary authentication indication, DN-AAA Server UE IP address allocation indication, DN-AAA Server addressing information, Edge Configuration Server Address Configuration Information, API based secondary authentication indication, UE authorization for EAS discovery via EASDF, HR-SBO authorization indication.

[0114] Session management subscription data may additionally include the following information: (Allowed / Subscribed / Optional / Preferred) PSA (PDU Session Anchor) UPF Functionalities, Set of Service data flow templates for each PSA UPF Functionalities.

[0115] (Allowed / Subscribed / Optional / Preferred) PSA(PDU Session Anchor) UPF Functionalities can contain a list of UPF Additional Functionalities that the PSA UPF responsible for the PDU Session being created must support. For example, the corresponding values ​​for UPF Additional Functions can include values ​​such as NAT, DPI, Firewall, etc. As another example, the supported UPF Additional Functions can be stored in the UPF Additional Functions list in the form of an index or a bitmap.

[0116] An example of a feature name listing: NAT, DPI, SPI, Firewall.

[0117] An example of an index format, 1: NAT, 2: DPI, 3: SPI, 4: Firewall.

[0118] An example of bitmap format: 00000001: NAT, 00000010: DPI, 00000100: SPI, 00001000: Firewall.

[0119] This patent does not limit the storage format of PSA UPF Functionalities to any specific method among the above embodiments.

[0120] The Set of Service data flow templates for each PSA UPF Functionalities is a filter for distinguishing service data flows to which each PSA UPF Functionality is applied. Service data flow templates can include values ​​for distinguishing IP flows, such as 5-tuple (Source IP address, Destination IP address, Source Port Number, Destination Port Number, Protocol) values, Domain Name, and Ethernet address. If the Set of Service data flow templates for each PSA UPF Functionalities is not applied, the PSA UPF Functionalities can be applied to all service data flows transmitted in the corresponding PDU Session.

[0121] In step 5, SMF may send Nsmf_PDUSession_CreateSMContext Response message or Nsmf_PDUSession_UpdateSMContext Response message to AMF. The message sent by SMF may include at least one of the following information: Cause, SM Context ID, or N1 SM Container (PDU Session Rejection Cause).

[0122] In step 6, a PDU session authentication / authorization procedure may be performed. More specifically, if Secondary Authentication / Authorization is required, the SMF may perform a PDU session establishment authentication / authorization procedure with the DN-AAA Server.

[0123] In step 7a, the SMF can select a PCF. More specifically, if dynamic PCC (Policy and Charging Control) is applied to the PDU Session, the SMF can select a PCF and establish an SM Policy Association.

[0124] According to one embodiment, the SMF may consider at least one of the following information to select a PCF for the PDU session being created: Local Operator Policies, DNN, S-NSSAI, SUPI, PCF Selected for UE, PCF Group ID provided by AMF, PCF Set ID, Same PCF Selection Indication.

[0125] In one embodiment, the SMF may establish an SM Policy Association with the PCF and request default PCC Rules for the PDU session.

[0126] In step 7b, the SMF can perform the PCF and SM Policy Association establishment procedure. The SMF can receive default PCC Rules from the PCF that are applied to the PDU session created through the SM Policy Association establishment procedure.

[0127] The SM Policy Association Establishment procedure is described in detail in Figure 5.

[0128] In step 8, the SMF can select a UPF to serve the PDU session it creates.

[0129] According to one embodiment, the SMF may consider at least one of the following information to select a UPF: UPF's Dynamic Load, UPF Location Available at SMF, DNN, PDU Session Type, SSC mode, UE Subscription Profile, DNAI, S-NSSAI, Access Technology, Information related to User Plane Topology, Support for UPF allocation of IP address / prefix, Support for High Latency Communication.

[0130] The SMF may additionally consider the following when selecting a UPF to serve a PDU session it creates: The PSA UPF Functionalities value (Allowed / Subscribed / Optional(Preferred)) received from the UDM or PCF. When selecting a PSA UPF, the SMF may select a UPF that includes UPF Functionalities included in the above values.

[0131] In step 9, the SMF can perform the SM Policy Association Modification procedure. The SM Policy Association Modification procedure allows the PCF to update its policy with the SMF. Additionally, the PCF can generate a PCC rule based on the URSP rule for the PDU Session.

[0132] In steps 10a and 10b, establishment and modification of N4 sessions may be performed between the SMF and the selected UPF. Referring to step 10a, for the establishment and modification procedures of the N4 session, the SMF may transmit at least one of the following information to the UPF: N4 Session ID, S-NSSAI, PDU Session Type, APN / DNN, Packet Detection Rules (PDR): Classifying traffic based on various criteria (e.g., 5-tuples), Forwarding Action Rules (FAR): Deciding whether to forward, drop, or buffer traffic, Multi-Access Rules (MAR): Handling traffic steering, switching, and splitting for MA PDU Session, Usage Routing Rules (URR): How to identify traffic for accounting and defining certain measurement to be reported, QoS Enforcement Rules (QER): QoS enforcement of traffic, Session Reporting Rules (SRR): Detecting and reporting events for PDU session.

[0133] SMF can send additional new and modified rules to UPF to apply UPF Functionalities.

[0134] Packet Functionality Rule (PFR)

[0135] AttributeDescriptionN4 Session IDIdentifies the N4 session associated to this PFRRule IDUnique identifier to identify this ruleUPF Functionality InformationPrecedenceDetermines the order, in which the UPF functionality of all available UPF functionalities is appliedUPF FunctionalityIdentifies the UPF functionality to apply to the packetParametersList of parameters for UPF functionality to apply to the packetDirection(UL, DL, Both)Determines which direction (UL, DL or Both) of the packet is applied by the UPF functionalityMandatory / OptionalIdentifies whether the UPF functionality to apply to the packet is mandatory or optionalConstraintsIdentifies any constraints of using UPF functionality in terms of time, amount of data and so on

[0136] 또한, PFR Rule을 서비스 데이터 플로우에 적용하기 위해서 기존 PDR Rule은 아래와 같이 수정될 수 있다.

[0137] AttributeDescriptionN4 Session IDIdentifies the N4 session associated to this PDRRule IDUnique identifier to identify this rule.PrecedenceDetermines the order, in which the detection information of all rules is applied.PacketDetectionInformationSource interfaceContains the values "access side", "core side", "SMF", "N6-LAN", "5G VN internal".UE IP addressOne IPv4 address and / or one IPv6 prefix with prefix lengthNetwork instanceIdentifies the Network instance associated with the incoming packet.CN tunnel infoCN tunnel info on N3, N9 interfaces, i.e. F-TEID.Packet Filter SetDetails see clause 5.7.6.Application identifier QoS Flow IDContains the value of 5QI or non-standardized QFI.Ethernet PDU SessionInformationRefers to all the (DL) Ethernet packets matching an Ethernet PDU session, as further described in clause 5.6.10.2 and in TS 29.244

[0065] .Framed Route InformationRefers to Framed Routes defined in clause 5.6.14.FQDN Filter for DNS QueryContains one or more FQDN, FQDN range, and / or any FQDN.Protocol DescriptionIndicates service protocol used by the flow (NOTE 8).Outer header removalInstructs the UP function to remove one or more outer header(s) (e.g. IP+UDP+GTP, IP + possibly UDP, VLAN tag), from the incoming packet.Packet Functionality Rule IDThe Packet Functionality Rule ID identifies a UPF functionality that has to be applied.Forwarding Action Rule IDThe Forwarding Action Rule ID identifies a forwarding action that has to be applied.Multi-Access Rule IDThe Multi-Access Rule ID identifies an action to be applied for handling forwarding for a MA PDU Session.List of Usage Reporting Rule ID(s)Every Usage Reporting Rule ID identifies a measurement action that has to be applied.List of QoS Enforcement Rule ID(s)Every QoS Enforcement Rule ID identifies a QoS enforcement action that has to be applied.

[0138] 또 다른 일 실시예로 새로운 PFR을 정의 하는 대신 기존 PDR Rule을 확장하는 방식을 이용 할 수도 있다.

[0139] A PDR rule like this can be a default PDR rule indicating that it applies to all service data flows in the UPF, if such a feature applies to all service data flows in the session.

[0140] AttributeDescriptionN4 Session IDIdentifies the N4 session associated to this PDRRule IDUnique identifier to identify this rule.PrecedenceDetermines the order, in which the detection information of all rules is applied.PacketDetectionInformationSource interfaceContains the values "access side", "core side", "SMF", "N6-LAN", "5G VN internal".UE IP addressOne IPv4 address and / or one IPv6 prefix with prefix lengthNetwork instanceIdentifies the Network instance associated with the incoming packet.CN tunnel infoCN tunnel info on N3, N9 interfaces, i.e. F-TEID.Packet Filter SetDetails see clause 5.7.6.Application identifier QoS Flow IDContains the value of 5QI or non-standardized QFI.Ethernet PDU SessionInformationRefers to all the (DL) Ethernet packets matching an Ethernet PDU session, as further described in clause 5.6.10.2 and in TS 29.244

[0065] .Framed Route InformationRefers to Framed Routes defined in clause 5.6.14.FQDN Filter for DNS QueryContains one or more FQDN, FQDN range, and / or any FQDN.Protocol DescriptionIndicates service protocol used by the flow (NOTE 8).Outer header removalInstructs the UP function to remove one or more outer header(s) (e.g. IP+UDP+GTP, IP + possibly UDP, VLAN tag), from the incoming packet.UPF Functionality InformationIdentifies the UPF functionality to apply to the packetForwarding Action Rule IDThe Forwarding Action Rule ID identifies a forwarding action that has to be applied.Multi-Access Rule IDThe Multi-Access Rule ID identifies an action to be applied for handling forwarding for a MA PDU Session.List of Usage Reporting Rule ID(s)Every Usage Reporting Rule ID identifies a measurement action that has to be applied.List of QoS Enforcement Rule ID(s)Every QoS Enforcement Rule ID identifies a QoS enforcement action that has to be applied.

[0141] According to one embodiment, UPF Functionality information to be applied to an existing PDR Rule can be added, and the UPF Functionality can be applied to a service data flow that matches the PDR.

[0142] Alternatively or additionally, information about packet capabilities applied to a PDU session may be provided to the UPF through other encodings or rules, not limited to the encodings described above (step 10a).

[0143] AttributeDescriptionN4 Session IDIdentifies the N4 session associated to this PDRCreate PDR IECreating Packet Detection RulesCreate FAR IECreating Forwarding action RulesCreate URR IECreate Usage Reporting RulesUPF Functionality InformationIdentifies the UPF functionality to apply (and / or applicable) to the packet(s) and / or the flow(s) of the PDU Session and / or for this N4 Session.It may identify the UPF functionalities that are applicable to this PDU Session / N4 SessionATSSS Control InformationFor providing or requesting ATSSS related information to / from the UPF.

[0144] At step 11, SMF may send a Namf_Communication_N1N2MessageTransfer message to AMF.

[0145] According to one embodiment, the message transmitted by the SMF may include at least one of the following information: PDU Session ID, N2 SM Information (PDU Session ID, QFI(s), QoS Profile(s), CN Tunnel Info, S-NSSAI from the Allowed NSSAI, Session-AMBR, PDU Session Type, User Plane Security Enforcement Information, UE Integrity Protection Maximum Data Rate, RSN, PDU Session Pair ID, TL-Container), N1 SM Container (PDU Session Establishment Accept / Reject)).

[0146] According to one embodiment, an N1 SM Container (PDU Session Establishment Accept) message included in a message transmitted by an SMF may include at least one of the following information: [QoS Rule(s) and QoS Flow level QoS parameters if needed for the QoS Flow(s) associated with the QoS rule(s)], Selected SSC mode, S-NSSAI(s), UE Requested DNN, Allocated IPv4 address, Interface Identifier, Session-AMBR, Selected PDU Session Type, [Reflective QoS Timer] (if available), [P-CSCF address(es)], [Control Plane Only Indicator], [Header Compression Configuration], [Always-On PDU Session Granted], [Small Data [Small Data Rate Control Parameters], [Small Data Rate Control Status], [Serving PLMN Rate Control], [PVS FQDN(s) and / or PVS IP address(es)]).

[0147] In step 12, the AMF may send a NAS message (e.g., N2 PDU Session Request) containing N2 SM Information and PDU Session Establishment Accept message to the (R)AN.

[0148] In step 13, the (R)AN may send the terminal a NAS message containing a PDU Session Establishment Accept message (e.g., AN-specific resource setup) received from the AMF.

[0149] At step 14, (R)AN may send an N2 PDU Session Response message to AMF.

[0150] According to one embodiment, the message transmitted by (R)AN may include at least one of the following information: PDU Session ID, Cause, N2 SM information (PDU Session ID, AN Tunnel Info, List of accepted / rejected QFI(s), User Plane Enforcement Policy Notification, TL-Container, Established QoS Flows Status (active / not active) for QoS Monitoring Configuration for Congestion Information, Established QoS Flows Status (active / not active) for ECN Marking for L4S, PDU Set Based Handling Support Indication).

[0151] In step 15, AMF may send an Nsmf_PDUSession_UpdateSMContext Request message to SMF. The message sent by AMF may include at least one of the following information: SM Context ID, N2 SM information, and Request Type.

[0152] In steps 16a and 17b, the SMF and the UPF may exchange N4 Session Modification Request / Response messages. In one embodiment, if a specific UPF feature is not supported due to a UP resource issue, the UPF feature may be disabled. If the PDU session establishment is rejected, the N4 session for the corresponding PDU session may also be released.

[0153] In step 16c, the SMF may perform a registration procedure with the UDM using the Nudm_UECM_Registration message with information related to the corresponding PDU session. The message transmitted by the SMF may include at least one of the following information: SUPI, DNN, S-NSSAI of HPLMN, PDU session ID, SMF identity, Serving Node PLMN ID, [NID].

[0154] In step 17, SMF may send an Nsmf_PDUSession_UpdateSMContext Response message to AMF.

[0155] In step 18, if the PDU Session Establishment procedure is not successful, the SMF can notify the AMF by sending the Nsmf_PDUSession_SMContextStatusNotify message.

[0156] In step 19, if the PDU Session Type requested for creation is IPv6 or IPv4v6, the SMF can create an IPv6 Router Advertisement message and transmit it to the terminal.

[0157] At step 20, if 5GS Bridge / Router Information is Available, SMF can initiate the PCF and SM Policy Association Modification procedure.

[0158] In step 21, if the PDU Session Establishment procedure fails, the SMF may disable the notification service for changes in Session Management Subscription data.

[0159] According to various embodiments of the present disclosure, each of the various procedures or steps disclosed in the above-described FIG. 4 may not be considered essential components, and may include at least one of some or a combination of some of the steps. Furthermore, the information contained in each message within the above-described procedures may not necessarily be considered essential elements, and only some of the information may be included. In addition, the names of the information are also merely examples, and any terminology may be used as long as it has substantially the same or similar meaning.

[0160] Figure 5 illustrates the SM Policy Association creation procedure for a PDU Session between an SMF and a PCF.

[0161] In Step 1, the SMF decides to create a PCF and SM Policy Association and sends the Npcf_SMPolicyControl_Create message to the selected PCF. This message may contain data received from other Network Functions (NFs) as well as information received from the UDM for PDU Session creation. This message may contain the following information: SUPI, PDU Session ID, DNN, S-NSSAI and RAT Type, PDU Session Type, Request Type, Access Type, IPv4 address and / or IPv6 prefix, PEI, GPSI, User Location Information, UE Time Zone, Serving Network identifier (PLMN ID, or PLMN ID and NID), Charging Characteristics information, Session-AMBR, subscribed default QoS information (5QI, 5QI Priority Level, ARP), UE support of reflective QoS, Number of supported packet filters for signalled QoS rules for the PDU Session, 3GPP PS Data Off status, Trace Requirements and Internal Group Identifier, DN Authorization Profile Index, DN authorized Session AMBR, Framed Route information, MA PDU Request indication, MA PDU Network-Upgrade Allowed indication, ATSSS capabilities of the MA PDU Session, QoS constraints from the VPLMN,Satellite backhaul category, list of NWDAF instance Ids (used by AMF, SMF, UPF) and corresponding Analytics ID(s), PVS IP address(es) and / or PVS FQDN(s) and Onboarding Indication in the case of ON-SNPN, URSP rule enforcement that including Connection Capability, PCF binding information (address(es) of PCF for UE, instance id of PCF for UE), HR-SBO support indication, Alternative S-NSSAI, URSP delivery in EPS support indication.,

[0162] 추가적으로 PSA UFP을 선택하기 위해서, Npcf_SMPolicyControl_Create 메시지에는 다음의 정보가 추가적으로 더 포함될 수 있다; Information regarding PSA UPF Functionalities: (Allowed / Subscribed / Optional(Preferred)) PSA UPF Functionalities, Set of Service data flow templates for each PSA UPF Functionalities.

[0163] In step 2, if the PCF does not have the UE's subscription information, the PCF may request and receive UE subscription related information from the UDR. This information may include: Allowed services, Subscriber categories, Subscribed GBR, ADC support, Subscriber spending limits control, Subscriber spending limits information, IP index information, Background Data Transfer Reference ID(s), Local routing indication, Service Function Chaining influence indication, Subscribed UE-Slice-MBR(s), Restricted Status, Charging related information (Default charging method, CHF address), Usage monitoring related information (Monitoring key, Usage monitoring level, Start date, End date, Volume limit, Time limit, Reset period), MPS subscription data (MPS priority, IMS signaling priority, MPS priority level, MCS priority, MCS priority level).

[0164] Additionally, to select a PSA UPF, the Subscription-related information may further include the following information: Information regarding PSA UPF Functionalities: (Allowed / Subscribed / Optional(Preferred)) PSA UPF Functionalities, Set of Service data flow templates for each PSA UPF Functionalities.

[0165] In step 3, PCF may request UE data usage related data (e.g. Initial Spending Limit Report Retrieval) from CHF.

[0166] In step 4, PCF can determine authorization and policy decisions based on all data received.

[0167] 단계 5에서 PCF는 결정된 policy information을 SMF에게 전송 할 수 있다. Dynamic PCC rule은 다음의 값들을 포함 할 수 있다; Rule identifier, Service data flow detection [Precedence, Service data flow template, Mute for notification], Charging [Charging key, Service identifier, Sponsor Identifier, Application Service Provider Identifier, Charging method, Service Data flow handling while requesting credit, Measurement method, Application Function Record Information, Service Identifier Level Reporting, Policy control [Gate status, 5G QoS Identifier (5QI), QoS Notification Control (QNC), Reflective QoS Control, UL-maximum bitrate, DL-maximum bitrate, UL-guaranteed bitrate, DL-guaranteed bitrate, UL sharing indication, DL sharing indication, Redirect, Redirect Destination, ARP, Bind to QoS Flow associated with the default QoS rule, Bind to QoS Flow associated with the default QoS rule and apply PCC rule parameters, PS to CS session continuity, Priority Level, Averaging Window, Maximum Data Burst Volume (MDBV),Disable UE notifications at changes related to Alternative QoS Profiles, Precedence for TFT packet filter allocation, ECN marking for L4S, Access Network Information Reporting [User Location Report, UE Timezone Report], Usage Monitoring Control [Monitoring key, Indication of exclusion from session level monitoring], N6-LAN Traffic Steering Enforcement Control [Traffic steering policy identifier(s), Metadata], Application Function influence on traffic routing Enforcement Control [Data Network Access Identifier, Per DNAI: Traffic steering policy identifier, Per DNAI: N6 traffic routing information, Information on AF subscription to UP change events, Indication of UE IP address preservation, Indication of traffic correlation, Information on User Plane Latency requirements, Indication for Simultaneous Connectivity at Edge Relocation, Information for EAS IP Replacement in 5GC, EAS Correlation indication, Traffic Correlation ID, Common EAS IP address, Common DNAI, FQDN(s), NEF information],NBIFOM related control Information [Allowed Access Type], RAN support information [UL Maximum Packet Loss Rate, DL Maximum Packet Loss Rate], MA PDU Session Control [Application descriptors, Steering Functionality, Steering Mode, Steering Mode Indicator, Threshold Values, Transport Mode, Charging key for Non-3GPP access, Monitoring key for Non-3GPP access], QoS Monitoring [QoS Monitoring parameter(s), Reporting frequency, Target of reporting, Indication of direct event notification], DataCollection_ApplicationIdentifier, Alternative QoS Parameter Sets [Packet Delay Budget, Packet Error Rate, UL-guaranteed bitrate, DL-guaranteed bitrate, Maximum Data Burst Volume (MDBV)], TSC Assistance Container, Traffic Parameter Information [Periodicity], Traffic Parameter Measurement [Traffic Parameter to be measured, Reporting condition], Downlink Data Notification Control [Notification control for DDD status, Notification Control for DDN Failure],PDU Set Control Information [PDU Set QoS Parameters (UL / DL)], Data Burst Handling Information [End of Data Burst Marking Indication], Protocol Description Information [Protocol Description (UL / DL)].,

[0168] Additionally, to select a PSA UPF, the Dynamic PCC rule may additionally include the following information: Information regarding PSA UPF Functionalities: (Allowed / Subscribed / Optional(Preferred)) PSA UPF Functionalities, Set of Service data flow templates for each PSA UPF Functionalities.

[0169] The table below shows various embodiments based on where the PSA UPF Functionalities information and Service Data Flow Template are stored.

[0170] No.UDM(Session Management Subscription data)PCFDescriptionPSA UPF FunctionalitiesService Data Flow TemplatePSA UPF FunctionalitiesService Data Flow Template1YESNONONOPredefined PCC ruleApplying UPF functionalities to all SDFs in PDU Session2YESYES(can be preconfigured in SMF instead of UDM)NONOPredefined PCC ruleApplying UPF functionalities to specific SDFs in PDU Session3YESNOYESNODynamic PCC ruleApplying UPF functionalities to all SDFs in PDU Session4YESNOYESYESDynamic PCC ruleApplying UPF functionalities to specific SDFs in PDU Session

[0171] The first embodiment is a case where only PSA UPF Functionalities information is stored in the UDM. In this embodiment, the Predefined PCC rule is applied by default. In the case of the Dynamic PCC rule using PCF, the PCC rule is continuously changed based on various information such as UE subscriber information, other information, current network status, network policy, etc., whereas the Predefined PCC rule provides a static PCC rule using the information about the user joining the network. In addition, since the Service Data Flow Template information is not used, the PSA UFP Functionalities can be applied to all service data flows transmitted using the corresponding PDU session.

[0172] The second embodiment is where both PSA UPF Functionalities information and Service Data Flow Template are stored in the UDM. In some cases, Service Data Flow Template information can be pre-configured in the SMF. In this embodiment, the Predefined PCC rule is applied by default. In this embodiment, since the Service Data Flow Template is applied, PSA UPF Functionalities can be applied only to certain service data flows among the service data flows transmitted using the PDU session.

[0173] The third embodiment is a case where only PSA UPF Functionalities information is stored in the UDM and PSA UPF Functionalities information changed using PCF are used. In this embodiment, the Dynamic PCC rule is applied. That is, the PSA UPF Functionalities stored when the user subscribes can change according to the current network conditions and network policies. Since this embodiment does not use Service Data Flow Template information, the PSA UPF Functionalities can be applied to all service data flows transmitted using the corresponding PDU session.

[0174] The fourth embodiment is a case where only PSA UPF Functionalities information is stored in the UDM, and PSA UPF Functionalities information changed using PCF and Service Data Flow Template generated by PCF using various information are used. In this embodiment, the Dynamic PCC rule is applied. Since this embodiment uses Dynamic PSA UPF Functionalities information and Dynamic Service Data Flow Template information, only the PSA UPF Functionalities most appropriate for the current situation can be applied to service data flows transmitted using PDU sessions.

[0175] Figure 6 illustrates the configuration of a terminal according to embodiments of the present disclosure.

[0176] A terminal according to one embodiment of the present disclosure may include a processor (620) that controls the overall operation of the terminal, a transceiver (600) including a transmitter and a receiver, and a memory (610). Of course, the terminal is not limited to the above-described examples, and the terminal may include more or fewer components than those illustrated in FIG. 6.

[0177] According to one embodiment of the present disclosure, the transceiver (600) can transmit and receive signals with network entities or other terminals. The signals transmitted and received with the network entities may include control information and data. In addition, the transceiver (600) can receive signals via a wireless channel, output them to the processor (620), and transmit the signals output from the processor (620) via the wireless channel.

[0178] According to one embodiment of the present disclosure, the processor (620) can control the terminal to perform any one of the operations described above. Meanwhile, the processor (620), the memory (610), and the transceiver (600) do not necessarily have to be implemented as separate modules, and of course, they can be implemented as a single component in the form of a single chip. In addition, the processor (620) and the transceiver (600) can be electrically connected. In addition, the processor (620) can include an Application Processor (AP), a Communication Processor (CP), a circuit, an application-specific circuit, a controller, or at least one processor.

[0179] According to one embodiment of the present disclosure, the memory (610) can store data such as basic programs, application programs, and setting information for the operation of the terminal. In particular, the memory (610) provides the stored data upon request of the processor (620). The memory (610) can be configured as a storage medium or a combination of storage media such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD. In addition, there can be a plurality of memories (610). In addition, the processor (620) can perform the above-described embodiments based on a program for performing the above-described embodiments of the present disclosure stored in the memory (610).

[0180] FIG. 7 illustrates a configuration of a base station or network entity according to embodiments of the present disclosure.

[0181] A network entity according to one embodiment of the present disclosure may include a processor (720) that controls the overall operation of the network entity, a transceiver (700) including a transmitter and a receiver, and a memory (710). Of course, the present invention is not limited to the above-described examples, and the network entity may include more or fewer components than those illustrated in FIG. 7.

[0182] According to one embodiment of the present disclosure, the transceiver (700) can transmit and receive signals with at least one of other network entities or terminals. The signals transmitted and received with at least one of the other network entities or terminals may include control information and data.

[0183] According to one embodiment of the present disclosure, the processor (720) can control a network entity to perform any one of the operations described above. Meanwhile, the processor (720), the memory (710), and the transceiver (700) do not necessarily have to be implemented as separate modules, and can of course be implemented as a single component in the form of a single chip. In addition, the processor (720) and the transceiver (700) can be electrically connected. In addition, the processor (720) can include an Application Processor (AP), a Communication Processor (CP), a circuit, an application-specific circuit, a controller, or at least one processor.

[0184] According to one embodiment of the present disclosure, the memory (710) can store data such as basic programs, application programs, and setting information for the operation of a network entity. In particular, the memory (710) provides the stored data upon request of the processor (720). The memory (710) can be configured as a storage medium or a combination of storage media such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD. In addition, there can be a plurality of memories (710). In addition, the processor (720) can perform the above-described embodiments based on a program for performing the above-described embodiments of the present disclosure stored in the memory (710).

[0185] It should be noted that the aforementioned configuration diagrams, examples of control / data signal transmission methods, examples of operational procedures, and configuration diagrams are not intended to limit the scope of the present disclosure. That is, not all components, entities, or operational steps described in the embodiments of the present disclosure should be construed as essential components for implementing the disclosure, and implementations may be made without detracting from the essence of the disclosure even if only some components are included. Furthermore, each embodiment may be combined and operated as needed. For example, parts of the methods proposed in the present disclosure may be combined to operate network entities and terminals.

[0186] The operations of the base station or terminal described above can be realized by providing a memory device storing the corresponding program code in any component within the base station or terminal device. That is, the control unit of the base station 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).

[0187] The various components and modules of the 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.

[0188] 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 include instructions that cause the electronic device to execute methods according to embodiments described in the claims or specification of the present disclosure.

[0189] These programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable read only memory (EEPROM), magnetic disc storage device, compact disc ROM (CD-ROM), digital versatile discs (DVDs) or other forms of optical storage device, magnetic cassette. Or, they may be stored in a memory configured as a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

[0190] Additionally, the program may be stored in 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.

[0191] In the specific embodiments of the present disclosure described above, components included in the disclosure are expressed singularly or plurally, 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 plural may be composed of singular elements, or components expressed in singular may be composed of plural elements.

[0192] While the detailed description of the present disclosure has described specific embodiments, it should be understood that various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments, but should be determined not only by the scope of the claims described below but also by equivalents thereof. In other words, it will be apparent to those skilled in the art that other modifications based on the technical idea of ​​the present disclosure are possible. In addition, the above-described embodiments can be combined and operated with each other as needed. For example, parts of the methods proposed in the present disclosure can be combined with each other to operate a base station and a terminal. In addition, although the above-described embodiments have been presented based on a 5G, NR system, other modifications based on the technical idea of ​​the above-described embodiments can be implemented with other systems such as LTE, LTE-A, and LTE-A-Pro systems.

Claims

1. In a method for operating SMF (session management function) in a wireless communication system, A step of receiving a PDU (protocol data unit) session creation request message from an AMF (access and mobility management function); A step of obtaining session management subscription data of a terminal from UDM (unified data management) based on the above PDU session creation request message; and A method comprising the step of determining a user plane function (UPF) for a PDU session to be created based on the above session management subscription data.

2. In paragraph 1, A method wherein the above session management subscription data includes information about a PSA (PDU session anchor) UPF function.

3. In paragraph 2, A method wherein the information about the UPF function includes information about the preferred PSA UPF function for the PDU session.

4. In paragraph 1, A method further comprising the step of transmitting information about a UPF function to be applied to the PDU session, with the determined UPF.

5. In paragraph 1, Further comprising a step of receiving a PCC (policy and charging control) rule for establishing the PDU session from a PCF (policy control function), A method wherein the UPF decision for the PDU session to be generated is determined additionally based on the PCC rule, wherein the PCC rule includes information about the PSA UPF function.

6. In a method for operating a PCF (policy control function) in a wireless communication system, A step of receiving a request message for creating a SM (session management) policy from an SMF (session management function); A step of generating a PCC (policy and charging control) rule based on the above request message; and A method comprising the step of transmitting the generated PCC rule to the above SMF.

7. In paragraph 6, It further includes a step of obtaining subscription-related information of the terminal from the UDR (united data repository), A method in which the above PCC rule is generated based additionally on the above subscription-related information.

8. In paragraph 6, It further includes a step of obtaining data related to the terminal's data usage from the CHF (charging function), A method in which the above PCC rule is generated based additionally on the above data usage related data.

9. In the SMF (session management function) operating in a wireless communication system, Transmitter and receiver; and Includes a control unit, The above control unit, Receive a PDU (protocol data unit) session creation request message from AMF (access and mobility management function), Based on the above PDU session creation request message, the terminal's session management subscription data is obtained from UDM (unified data management), An SMF configured to determine a user plane function (UPF) for a PDU session to be created based on the above session management subscription data.

10. In paragraph 9, The above session management subscription data includes information about the PSA (PDU session anchor) UPF function, SMF.

11. In paragraph 10, Information about the above UPF function, SMF, which includes information about the preferred PSA UPF function for the PDU session.

12. In paragraph 9, The above control unit, An SMF further configured to transmit information about the UPF functions to be applied to the PDU session, with the determined UPF.

13. In paragraph 9, The above control unit, It is further configured to receive a PCC (policy and charging control) rule for establishing the PDU session from a PCF (policy control function), It is further set to determine the UPF decision for the PDU session to be generated based on the PCC rule. The above PCC rule contains information about the PSA UPF function, SMF.

14. In a PCF (policy control function) operating in a wireless communication system, Transmitter and receiver; and Includes a control unit, The above control unit, Receive a request message for creating a session management (SM) policy from the session management function (SMF), Generates a PCC (policy and charging control) rule based on the above request message, PCF, which is set to transmit the generated PCC rules to the above SMF.

15. In paragraph 14, The above control unit, It is further configured to obtain subscription-related information of the terminal from the UDR (united data repository), The generation of the above PCC rule is additionally generated based on the above subscription-related information, PCF.

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