Apparatus and method for controlling network slice data rate in wireless communication system

Abstract

The present disclosure relates to a 5th-Generation (5G) or pre-5G communication system for supporting higher data rates following a 4th-Generation (4G) communication system, such as Long Term Evolution (LTE). According to various embodiments, a method for operating a network node in a wireless communication system is provided. The method includes obtaining slice policy information including a maximum data rate, monitoring data rates of protocol data unit (PDU) sessions associated with a slice, determining whether a sum of the data rates of the PDU sessions associated with the slice exceeds the maximum data rate, a policy enforcement request message for controlling the sum of the data rates of the PDU sessions associated with the slice is sent to the second network node.

Description

[0001] This application is a divisional application of the invention patent application with the application date of January 6, 2021, application number: 202110011487.3, and invention name: "Apparatus and method for controlling network slice data rate in wireless communication system". Technical Field

[0002] The present disclosure relates to a wireless communication system. More specifically, the present disclosure relates to an apparatus and method for controlling a network slice data rate in a wireless communication system. Background Art

[0003] In order to meet the needs of increased wireless data services since the deployment of the fourth generation (4G) communication system, efforts have been made to develop improved fifth generation (5G) or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "beyond 4G networks" or "post-Long Term Evolution (LTE) systems".

[0004] 5G communication systems are considered to be implemented at higher frequency (millimeter (mm) wave) bands, such as the 60 gigahertz (GHz) band, to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technology are discussed in 5G communication systems.

[0005] In addition, in 5G communication systems, development of system network improvements is being carried out based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communications, wireless backhaul, mobile networks, cooperative communications, coordinated multi-point (CoMP), receiving-end interference cancellation, etc.

[0006] In 5G systems, hybrid frequency shift keying (FSK) and quadrature amplitude modulation (QAM) (FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coding modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies.

[0007] For the 5G system, research is being conducted to support a wider variety of services than the existing 4G system. For example, the most representative services of the 5G system include enhanced mobile broadband (eMBB) service, ultra-reliable and low-latency communication (URLLC) service, massive machine type communication (mMTC) service, evolved multimedia broadcast / multicast service (eMBMS), and the like.

[0008] The above information is presented as background information only to assist with an understanding of the present disclosure. No determination is made, and no assertion is made, as to whether any of the above may be applicable as prior art with respect to the present disclosure. Summary of the invention

[0009] An aspect of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the following advantages. Therefore, an aspect of the present disclosure is to provide an apparatus and method for controlling a network slice data rate in a wireless communication system.

[0010] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0011] According to one aspect of the present disclosure, a method for operating a network node in a wireless communication system is provided. The method includes: obtaining slice policy information including a maximum data rate; monitoring a data rate of a protocol data unit (PDU) session associated with a slice; determining whether the sum of the data rates of the PDU sessions associated with the slice exceeds the maximum data rate; and sending a policy enforcement request message for controlling the sum of the data rates of the PDU sessions associated with the slice to a second network node.

[0012] According to another aspect of the present disclosure, a network node in a wireless communication system is provided. The network node includes: at least one transceiver; and at least one processor. The at least one processor is configured to: obtain slice policy information including a maximum data rate, monitor the data rate of a protocol data unit (PDU) session associated with the slice, determine whether the sum of the data rates of the PDU sessions associated with the slice exceeds the maximum data rate, and send a policy enforcement request message for controlling the sum of the data rates of the PDU sessions associated with the slice to a second network node.

[0013] According to another aspect of the present disclosure, a method for operating a policy control function PCF in a wireless communication system is provided, the method comprising: obtaining network slice-related policy information, the network slice-related policy information comprising a maximum data rate of a network slice of a single network slice selection assistance information (S-NSSAI), wherein the maximum data rate comprises a maximum bit rate (MBR) of a guaranteed bit rate (GBR) quality of service (QoS) flow and an aggregate maximum bit rate (AMBR) of a non-guaranteed bit rate (non-GBR) QoS flow; monitoring a data rate associated with the network slice; determining whether the data rate associated with the network slice exceeds the maximum data rate; and in a case where it is determined that the data rate associated with the network slice exceeds the maximum data rate, changing the AMBR of the non-GBR QoS flow so as not to exceed the maximum data rate.

[0014] According to another aspect of the present disclosure, a device of a policy control function (PCF) in a wireless communication system is provided, the PCF device comprising: a transceiver; and at least one processor, configured to: obtain network slice-related policy information, the network slice-related policy information comprising a maximum data rate of a network slice of a single network slice selection auxiliary information (S-NSSAI), wherein the maximum data rate comprises a maximum bit rate MBR of a guaranteed bit rate (GBR) quality of service (QoS) flow and an aggregate maximum bit rate (AMBR) of a non-guaranteed bit rate (non-GBR) QoS flow; monitor a data rate associated with the network slice; determine whether the data rate associated with the network slice exceeds the maximum data rate; and in a case where it is determined that the data rate associated with the network slice exceeds the maximum data rate, change the AMBR of the non-GBR QoS flow so as not to exceed the maximum data rate.

[0015] Apparatus and methods according to various embodiments may advantageously provide apparatus and methods for controlling network slice data rates in a wireless communication system.

[0016] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the accompanying drawings, discloses various embodiments of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0018] Figure 1A is a diagram illustrating a structure of a wireless communication system according to an embodiment of the present disclosure;

[0019] Figure 1B is a diagram illustrating a configuration of a network entity in a wireless communication system according to an embodiment of the present disclosure;

[0020] Figure 2 is a diagram illustrating a process of collecting slice data rate and data usage from a base station in a wireless communication system according to an embodiment of the present disclosure;

[0021] Figure 3 is a diagram illustrating a process of collecting slice data rate and data usage from a network function (NF) in a wireless communication system according to an embodiment of the present disclosure;

[0022] Figure 4 is a diagram illustrating a registration procedure or a protocol data unit (PDU) session establishment procedure in a wireless communication system according to an embodiment of the present disclosure;

[0023] Figure 5is a diagram illustrating a PDU session establishment process in a wireless communication system according to an embodiment of the present disclosure;

[0024] Figure 6 is a diagram illustrating a PDU session modification process in a wireless communication system according to an embodiment of the present disclosure; and

[0025] Figure 7 is a flowchart illustrating an operation process of a NF in a wireless communication system according to an embodiment of the present disclosure.

[0026] Throughout the drawings, like reference numerals will be understood to refer to like parts, components, and structures. DETAILED DESCRIPTION

[0027] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in understanding but they are considered to be exemplary only. Therefore, one of ordinary skill in the art will recognize that various changes and modifications of the various embodiments described herein may be made without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and structures may be omitted for clarity and conciseness.

[0028] The terms and words used in the following description and claims are not limited to the literal meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustrative purposes only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0029] It will be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0030] Hereinafter, various embodiments of the present disclosure will be described based on a hardware method. However, various embodiments of the present disclosure include techniques using both hardware and software, and therefore various embodiments of the present disclosure may not exclude aspects of software.

[0031] In the following description, for convenience of explanation, terms related to signals, terms related to channels, terms related to control information, terms related to network entities, terms related to device elements, etc. are used. Therefore, the present disclosure is not limited by the terms used below, and other terms related to the subject matter having equivalent technical meanings may be used.

[0032] In the following description, for convenience of explanation, terms used to identify access nodes, terms related to network entities or network functions (NFs), terms related to messages, terms related to interfaces between network entities, terms related to various identification information, etc. are used. Therefore, the present disclosure is not limited by the terms used below, and other terms related to the subject matter having equivalent technical meanings may be used.

[0033] In the following description, for ease of description, the present disclosure will be described using terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) and 5G standards. However, the present disclosure is not limited by these terms and names, and can be applied to systems conforming to other standards in the same manner.

[0034] Hereinafter, for convenience of explanation, the name of NF (e.g., access and mobility management function (AMF), session management function (SMF), network slice selection function (NSSF), etc.) is used as a target for exchanging information for access control and state management. However, even if NF is actually implemented as an instance (AMF instance, SMF instance, NSSF instance, etc.), the embodiments of the present disclosure can be applied in the same manner.

[0035] Figure 1A is a diagram illustrating a structure of a wireless communication system according to an embodiment of the present disclosure.

[0036] refer to Figure 1A , which illustrates the architecture of the fifth generation system (5GS).

[0037] The 5G system (5GS) includes terminals (user equipment (UE)), base stations ((radio) access networks ((R)AN) and 5G core networks (5GC). The 5G core network may include access and mobility management functions (AMF), session management functions (SMF), user plane functions (UPF), policy control functions (PCF), user data management (UDM), network slice selection functions (NSSF), network data analysis functions (NWDAF), and so on.

[0038] Figure 1A Only one terminal, one base station, and one NF of the 5G core network are illustrated, but other terminals, other base stations, and other nodes that are the same as or similar to the NF of the 5G core network may be further included.

[0039] A base station is a network infrastructure that provides radio access to a terminal. A base station has coverage defined as a certain geographical area based on the distance over which a signal can be sent. A base station may be referred to as an "access point (AP)", "eNodeB (eNB)", "5G node (fifth generation node)", "gNodeB (gNB)", "radio point", "transmit / receive point (TRP)", or other terms with equivalent technical meanings other than a base station.

[0040] A terminal is a device used by a user and communicates with a base station through a radio channel. In some cases, a terminal can operate without user participation. In this case, a terminal is a device that performs machine type communication (MTC) and may not be carried by a user. A terminal may be referred to as a "user equipment (UE)", "mobile station", "user station", "remote terminal", "wireless terminal", "user device" or another term with an equivalent technical meaning other than a terminal.

[0041] The terminal can access the 5G core network through the base station. The terminal can connect to the AMF and N2 interfaces through the base station, and can connect to the UPF and N3 interfaces.

[0042] The Access and Mobility Management Function (AMF) is a network function (NF) that manages the wireless network access and mobility of the terminal (UE).

[0043] The Session Management Function (SMF) is an NF that manages sessions of a terminal, and session information includes Quality of Service (QoS) information, charging information, and packet processing information. The connection between the terminal and the SMF may be a Packet Data Unit (PDU) session.

[0044] The user plane function (UPF) is a NF that processes user plane services and is controlled by the SMF. The UPF may be a gateway through which packets sent and received by the terminal are sent or a network entity that serves as a gateway. The UPF may be connected to a data network (DN) connected to the Internet and may provide a path for sending and receiving data between the terminal and the DN. Therefore, the UPF may route data to be sent through the Internet among packets sent by the terminal through the Internet data network.

[0045] A Policy Control Function (PCF) is an NF that manages operator policies for providing services in a wireless communication system.

[0046] User Data Management (UDM) is the NF that stores and manages UE subscription information.

[0047] The Unified Data Repository (UDR) is a NF that stores and manages data. The UDR can store terminal subscription information and provide the terminal subscription information to the UDM. In addition, the UDR can store operator policy information and provide the operator policy information to the PCF.

[0048] The network data analysis function (NWDAF) is an NF that provides analysis information for the operation of the 5G system. The NWDAF can collect data from other NFs or operations, administration, and maintenance (OAM) constituting the 5G system, analyze the collected data, and provide the analysis results to other NFs.

[0049] The Network Slice Selection Function (NSSF) is the NF that performs the operation of selecting a network slice.

[0050] The Authentication Server Function (AUSF) is a NF that provides services for user authentication processing.

[0051] The Network Exposure Function (NEF) is an NF that can access terminal management information in the 5G network and send subscriptions to mobility management events of the corresponding terminal, subscriptions to session management events of the corresponding terminal, requests for information about sessions, configuration of charging information of the corresponding terminal, PDU session policy for change requests of the corresponding terminal, and small data about the corresponding terminal.

[0052] A Network Repository Function (NRF) is a NF that stores state information of NFs and has the function of processing requests to find NFs to which other NFs can access.

[0053] The application function (AF) is a NF having a function of providing services to users by interworking with a mobile communication network.

[0054] Service Communication Agent (SCP) is a NF that provides functions such as NF discovery for communication between NFs and information transfer between NFs. SCP can operate in an integrated form with NRF depending on the operator's choice, and in this case, SCP can include the functions of NRF, or conversely, NRF can include the functions of SCP.

[0055] In the 3GPP system, the conceptual link connecting NFs in the 5G system is defined as a reference point. Figure 1A Reference points included in the 5G system architecture represented in.

[0056] -N1: Reference point between UE and AMF

[0057] -N2: Reference point between (R)AN and AMF

[0058] -N3: Reference point between (R)AN and UPF

[0059] -N4: Reference point between SMF and UPF

[0060] -N5: Reference point between PCF and AF

[0061] -N6: Reference point between UPF and DN

[0062] -N7: Reference point between SMF and PCF

[0063] -N8: Reference point between UDM and AMF

[0064] -N9: Reference point between two core UPFs

[0065] -N10: Reference point between UDM and SMF

[0066] -N11: Reference point between AMF and SMF

[0067] -N12: Reference point between AMF and AUSF

[0068] -N13: Reference point between UDM and Authentication Server Function (AUSF)

[0069] -N14: Reference point between two AMFs

[0070] - N15: Reference point between PCF and AMF in case of non-roaming scenario, and between PCF and AMF in visited network in case of roaming scenario

[0071] In the following, for ease of description, the target for exchanging information for access control and state management will be collectively described as NF. However, even if NF is actually implemented as an instance (AMF instance, SMF instance, NSSF instance, etc.), the various embodiments of the present disclosure can be applied in the same way.

[0072] In various embodiments of the present disclosure, an instance may have a specific NF in the form of software code, and may mean a state in which physical and / or logical resources are allocated from a computing system and are executable to perform the functions of an NF in a physical computing system (e.g., a specific computing system present on a core network). Therefore, an AMF instance, an SMF instance, and an NSSF instance may mean that physical and / or logical resources are allocated from a specific computing system present on a core network and are used for AMF, SMF, and NSSF operations, respectively. An AMF instance, an SMF instance, and an NSSF instance may use physical or / and logical resources allocated from a specific computing system present on a network for AMF, SMF, and NSSF operations. As a result, an AMF instance, an SMF instance, and an NSSF instance may perform the same operations as when physical AMF, SMF, and NSSF devices exist. Therefore, in various embodiments of the present disclosure, things described as NFs (AMF, SMF, UPF, NSSF, NRF, SCP, etc.) may be replaced with NF instances, or conversely, things described as NF instances may be replaced with NFs. Similarly, in various embodiments of the present disclosure, things described as network slices may be replaced with network slice instances, or conversely, things described as network slice instances may be replaced with network slices.

[0073] According to various embodiments of the present disclosure, in a 5G system defined by 3GPP, one network slice may be referred to as a single network slice selection assistance information (S-NSSAI). S-NSSAI may include a slice / service type (SST) value and a slice differentiator (SD) value. SST may represent the characteristics of services supported by the slice (e.g., enhanced mobile broadband (eMBB), Internet of Things (IoT), ultra-reliable low latency communication (URLLC), vehicle-to-everything (V2X), etc.). SD may be a value used as an additional identifier for a specific service referred to as SST.

[0074] NSSAI may include one or more S-NSSAIs. Examples of NSSAI include configured NSSAI stored in the terminal (configured NSSAI), NSSAI requested from the terminal (NSSAI), NSSAI allowed to be used by the terminal determined by the NF of the 5G core network (e.g., AMF, NSSF, etc.) (allowed NSSAI), and subscribed NSSAI (NSSAI) subscribed by the terminal, and are not limited to the above examples.

[0075] Meanwhile, in various embodiments of the present disclosure, the data rate may be applied to the downlink or uplink. If separate values ​​are applied to the uplink / downlink links, signaling may be sent separately (e.g., the maximum bit rate of the network slice aggregation for the downlink, or the maximum bit rate of the network slice aggregation for the uplink).

[0076] Figure 1B is a diagram illustrating a configuration of a network entity in a wireless communication system according to an embodiment of the present disclosure.

[0077] In various embodiments of the present disclosure, a network entity is a concept including a network function (NF) implemented according to a system. Terms such as "-unit" and "-group" used hereinafter refer to a unit that processes at least one function or operation, which can be implemented as hardware or software, or a combination of hardware and software.

[0078] refer to Figure 1B , the network entity according to various embodiments may include a communication unit 110 , a storage unit 120 , and a controller 130 that controls overall operations of the network entity 100 .

[0079] The communication unit 110 transmits and receives signals with other network entities. Therefore, all or part of the communication unit 110 may be referred to as a transmitter 111, a receiver 113, or at least one transceiver.

[0080] The storage unit 120 stores data such as basic programs, application programs, and configuration information for the operation of the network entity 100. The storage unit 120 may include a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. In addition, the storage unit 120 provides the stored data according to a request of the controller 130.

[0081] The controller 130 controls the overall operation of the network entity 100. For example, the controller 130 sends and receives signals through the communication unit 110. In addition, the controller 130 writes and reads data in the storage unit 120. In addition, the controller 130 can perform the functions of the protocol stack required by the communication standard. To this end, the controller 130 may include a circuit, an application specific integrated circuit, at least one processor or a microprocessor, or may be a part of a processor. In addition, the communication unit 110 and a part of the controller 130 may be referred to as a communication processor (CP). The controller 130 may control the network entity 100 to perform any one operation of the various embodiments.

[0082] The communication unit 110 and the controller 130 do not have to be implemented as separate modules, but can be implemented as a single component in the form of a single chip or a software block. The communication unit 110, the storage unit 120 and the controller 130 can be electrically connected. In addition, the operation of the network entity 100 can be implemented by causing the storage unit 120 to store the corresponding program code in the network entity 100.

[0083] The network entity 100 includes a network node, and the network node can be any one of a base station (RAN), a terminal (UE), a NF, an AMF, an SMF, an UPF, a NEF, an NRF, a PCF, an NSSF, an UDM, an AF, an AUSF, an SCP, an UDSF, a context storage device, an OAM, an EMS, a configuration server, and an ID management server.

[0084] According to various embodiments, the 5G system may include a terminal, a base station and a 5G core network. The 5G core network may include network functions (NFs) such as AMF, SMF, PCF, UPF, UDM, UDR, NEF, NSSF, NRF and SCP. According to various embodiments of the present disclosure, the network function (NF) may refer to a network entity (NE) and a network resource. The next generation radio access network (NG-RAN, 5G-RAN, RAN) refers to a base station that provides wireless communication functions to the terminal. User equipment (UE) can access the 5G core network through the base station.

[0085] The various network functions described below may include a specific physical device or two or more physical devices. In addition, each physical device may include a program or software for executing the method described below under the control of the processor included therein. In the following description, although the names of the various NFs are presented only for the convenience of explanation, they are implemented as a physical device including at least one processor as described above, and it is obvious to those skilled in the art that the program or software for the operation described in this disclosure can be installed. Therefore, the expression "device" will be omitted below, and it will only be described by the name of a specific NF.

[0086] Example 1

[0087] Example 1 describes a method for a mobile communication service provider to operate a network slice.

[0088] The mobile communication service provider may define the size of the network resources that may be provided for each network slice. In various embodiments of the present disclosure, this is referred to as a network slice strategy or a slice strategy. The slice strategy information may include the following information.

[0089] -S-NSSAI

[0090] - Maximum number of UEs

[0091] - Maximum number of PDU sessions

[0092] -Maximum data rate

[0093] The S-NSSAI included in the slice policy information according to various embodiments is an identifier representing a slice. A mobile communication service provider may use a network slice instance (NSI) identifier (ID) instead of S-NSSAI as an identifier representing such a slice.

[0094] The maximum number of terminals included in the slice policy information according to various embodiments may indicate the number of terminals allowed to use S-NSSAI. The terminal may send network slice information (requested NSSAI) to be used during a registration process (registration process or attachment process) to the AMF, and the AMF may provide the terminal with network slice information (allowed NSSAI) that can be used by the terminal.

[0095] The maximum number of terminals may indicate the maximum value of the number of terminals that have received the allowed NSSAI including the corresponding S-NSSAI during the registration process. For example, if the maximum number of UEs in an eMBB slice is one million, the 5G core network may send the allowed NSSAI including the S-NSSAI indicating the eMBB slice to a maximum of one million UEs.

[0096] According to various embodiments of the present disclosure, the maximum number of sessions included in the slice policy information may indicate the number of sessions (PDU sessions or packet data network (PDN) connections) established using S-NSSAI. In the session establishment process (PDU session establishment process or PDN connection establishment process), the terminal may send a PDU session establishment request message to the 5G core network, which includes the slice information (S-NSSAI) to be used, and the 5G core network may process the session establishment request from the terminal to establish the session.

[0097] The maximum number of sessions may represent the maximum value of sessions established with the corresponding S-NSSAI during the session establishment process. For example, if the maximum number of sessions in an eMBB slice is three million, the 5G core network may allow up to three million sessions for the number of sessions established with the S-NSSAI, where the eMBB slice refers to the eMBB slice.

[0098] According to various embodiments of the present disclosure, the maximum number of sessions of an eMBB slice may be calculated as the product of the maximum number of terminals of the eMBB slice (e.g., one million sessions) and the maximum number of sessions that each terminal may establish (e.g., three sessions). Alternatively, according to various embodiments of the present disclosure, the maximum number of sessions that each terminal may establish using an eMBB slice may be calculated as a value obtained by dividing the maximum number of sessions of an eMBB slice (e.g., three million sessions) by the maximum number of terminals of an eMBB slice (e.g., one million terminals).

[0099] The maximum data rate / usage included in the slice policy information according to various embodiments may indicate a transmission rate of user plane data sent in a session established using S-NSSAI. For example, if the maximum data capacity of an eMBB slice is three million terabytes, the 5G core network may allow up to three million terabytes per second (Tbps) of data to be sent in a session established with S-NSSAI, and the eMBB slice refers to an eMBB slice.

[0100] The slice policy information can be configured in the NF of the 5G core network (e.g., AMF, PCF, NSSF, NWDAF, UDM, etc.). For example, the mobile communication service provider can configure the slice policy information in the NF of the 5G core network in the form of OAM. Alternatively, the NF of the 5G core network (e.g., AMF, etc.) can obtain the slice policy information from the NF of another 5G core network (e.g., PCF, NSSF, NWDAF, UDM, etc.).

[0101] Various methods can be used for mobile communication service providers to enforce slicing policy information.

[0102] According to various embodiments of the present disclosure, when the number of currently registered terminals of the corresponding S-NSSAI exceeds the maximum number of registered terminals, the NF of the 5G core network may reject subsequent registration requests.

[0103] According to various embodiments of the present disclosure, when the number of currently established sessions of the corresponding S-NSSAI exceeds the maximum number of sessions, the NF of the 5G core network may reject subsequent PDU session establishment requests.

[0104] According to various embodiments of the present disclosure, when the current data rate / usage rate of S-NSSAI exceeds the maximum data rate / usage rate, the NF of the 5G core network may reject the registration request of S-NSSAI. The details will be described later in Embodiment 2.

[0105] According to various embodiments of the present disclosure, when the current data rate / usage rate of S-NSSAI exceeds the maximum data rate / usage rate, the NF of the 5G core network may reject the PDU session request of S-NSSAI. The details will be described later in Embodiment 3.

[0106] According to various embodiments of the present disclosure, when the current data rate / usage rate of S-NSSAI exceeds the maximum data rate / usage rate, the NF of the 5G core network can reduce the data rate / usage rate of all PDU sessions established with S-NSSAI. The details will be described later in Embodiments 4 and 5.

[0107] Figure 2 is a diagram illustrating a process of collecting slice data rate and data usage from a base station in a wireless communication system according to an embodiment of the present disclosure.

[0108] refer to Figure 2 , at operation 210, the NF (e.g., AMF, SMF, PCF, NSSF, NRF, NWDAF, UDM, etc.) of the 5G core network 202 is an NF that manages a slice policy (e.g., data rate / usage rate). The NF 202 manages base station information (e.g., RAN node ID, cell ID, etc.) supporting a slice called a slice ID (S-NSSAI or SST).

[0109] At operation 210, NF 202 may request a slice data rate monitoring report from the base station through the AMF. Alternatively, NF 202 may be an AMF. For example, NF 202 is a NF that manages the data rate of eMBB slices (eMBB S-NSSAI or eMBB SST), and NF 202 knows that the first base station 200 and the second base station 201 support eMBB slices. At operation 210, NF 202 may send a monitoring report request message to the first base station 200. In addition, at operation 218, NF 202 may send a monitoring report request message to the second base station 201.

[0110] The slice ID and the monitoring condition of the related slice may be included in the monitoring report request message of operations 210 and 218. For example, the monitoring condition may include time (period) information for sending the monitoring report message, data usage information for sending the monitoring report message, and event information for sending the monitoring report message.

[0111] In operation 212, the first base station 200 may store the slice ID and the slice monitoring condition received through the monitoring report request message in operation 210, and determine whether the monitoring condition is satisfied.

[0112] For example, when the monitoring condition includes time (period) information (eg, once every two hours, once a day, 4:00am, etc.), the first base station 200 may send the monitoring report message of operation 214 when the timing or period according to the condition arrives.

[0113] For example, when the monitoring condition includes data usage information (for example, 1T bytes of cumulative data usage, etc.), the first base station 200 may send a monitoring report message in operation 214 when the cumulative data usage generated in a network slice referred to as a slice ID reaches the data usage described in the condition.

[0114] For example, if the monitoring conditions include event information (for example, when the requested slice data rate is not met, when the first base station 200 reaches the maximum data rate that can be enforced, etc.), the first base station 200 can send a monitoring report message of operation 214 when the corresponding event occurs.

[0115] For example, after the first base station 200 receives the monitoring report request message of step 210 , or when the current data usage / transmission volume report indicator is included in the monitoring report request message, the first base station 200 may send the monitoring report message in operation 214 .

[0116] In operation 214, the base station 200 may transmit a monitoring report message to the NF 202. The monitoring report may include a slice ID, accumulated data usage, current data rate, error status, and occurred event information.

[0117] In operation 216, NF 202 stores and manages data usage information for the received slice ID.

[0118] In the process from operations 218 to 224, when one or more base stations support slicing, NF 202 may perform the process from operations 210 to 216 with the second base station 201 that supports slicing. Although for ease of explanation, message transmission and reception between NF 202 and the first base station 200 are first described in the process from operations 210 to 216, and then message transmission and reception between NF 202 and the second base station 201 are described in the process from operations 218 to 224, message transmission and reception between NF 202 and the first base station 200 and message transmission and reception between NF 202 and the second base station 201 may occur independently.

[0119] In operation 226, NF 202 may comprehensively manage and monitor data usage of the slice based on information collected from the slice-supporting base stations 200 and 201. In other words, NF 202 may enforce policies.

[0120] For example, the accumulated data usage of the slice managed by NF 202 may be the sum of the accumulated data usage received from the first base station 200 in operation 214 and the accumulated data usage received from the second base station 201 in operation 222 .

[0121] Figure 3 is a diagram illustrating a process of collecting slice data rate and data usage from NF in a wireless communication system according to an embodiment of the present disclosure.

[0122] refer to Figure 3, hereinafter, for ease of description, NF 302 is described as a NF of a 5G core network, but according to various embodiments of the present disclosure, NF 302 may be an AF.

[0123] At operation 310, NF 302 (e.g., AMF, SMF, PCF, NSSF, NRF, NWDAF, UDM, etc.) of the 5G core network is an NF that manages a slice policy (e.g., data rate / usage rate). NF 302 manages NFs (NFID, NF address, etc.) that support slices called slice IDs (S-NSSAI or SST).

[0124] At operation 310, NF 302 may request a monitoring report on a data rate of a slice from NFs 202 and 300 (e.g., AMF, SMF, PCF, NRF, etc.) supporting a slice called a corresponding slice ID. For example, NF 302 is a NF that manages a data rate of an eMBB slice (eMBB S-NSSAI or eMBB SST). NF 302 knows that the first NF 202 and the second NF 300 support eMBB slices. At operation 310, NF 302 may send a monitoring report request message to the first NF 202. In addition, at operation 318, NF 302 may send a monitoring report request message to the second NF 300.

[0125] The first NF 202 and the second NF 300 may manage data usage / transmission rates used in slices called slice IDs. For example, during the PDU session establishment process, the first NF 202 and the second NF 300 may collect data rate information related to the slice (e.g., aggregate maximum bit rate (AMBR), guaranteed bit rate (GBR) flow data rate, non-GBR flow data rate, etc.). Alternatively, for example, the first NF 202 and the second NF 300 may manage the data usage / transmission rates used in the slices called slice IDs. Figure 2 The process shown collects data rate information from base stations.

[0126] The messages of operations 310 and 318 may include a slice ID and monitoring conditions related to the slice. For example, the monitoring conditions may include time (period) information for sending a monitoring report message, data usage information for sending a monitoring report message, and event information for sending a monitoring report message.

[0127] In operation 312, the first NF 202 may store the slice ID and the slice monitoring condition received in operation 310, and determine whether the monitoring condition is satisfied.

[0128] For example, when the monitoring condition includes time (periodic) information (eg, once every two hours, once a day, 4am, etc.), the first NF may send a message of operation 314 when the timing or period according to the condition arrives.

[0129] For example, when the monitoring condition includes data usage information (e.g., 1T-byte cumulative data usage, etc.), the first NF202 may send a monitoring report message of operation 314 when the cumulative data usage generated in a network slice referred to as a slice ID reaches the data usage described in the condition.

[0130] For example, if the monitoring condition includes event information (for example, when the requested slice data rate is not met, the first NF reaches the maximum data rate that can be enforced, etc.), the first NF can send a monitoring report message in operation 314 when the corresponding event occurs.

[0131] For example, after the first NF 202 receives the monitoring report request message of operation 310 , or when the current data usage / transmission volume report indicator is included in the monitoring report request message, the first NF 202 may send the monitoring report message of operation 314 .

[0132] At operation 314, the first NF 202 sends a monitoring report message to the NF 302 of the 5G core network. The monitoring report may include a slice ID, accumulated data usage, current data rate, error status, and event information that occurred. According to various embodiments of the present disclosure, the NF 302 of the 5G core network may be an application function (AF).

[0133] In operation 316, the NF 302 stores and manages data usage information for the received slice ID.

[0134] In the process from operations 318 to 324, if one or more NFs 202 and / or 300 support slicing, the NF 302 may perform the process from operations 310 to 316 with the second NF 300 supporting slicing. Although for ease of explanation, message transmission / reception between the NF 302 and the first NF 202 is first described in the process from operations 310 to 316, and then message transmission / reception between the NF 302 and the second NF 300 is described in the process from operations 318 to 324, the message transmission / reception between the NF 302 and the first NF 202 and the message transmission / reception between the NF 302 and the second NF 300 may occur independently.

[0135] In operation 326, NF 302 may comprehensively manage and monitor data usage of the slice based on information collected from NFs 300 and 202 supporting the slice. For example, NF 302 may enforce policies.

[0136] For example, the accumulated data usage of the slice managed by NF 302 may be the sum of the accumulated data usage received from the first NF 202 in operation 314 and the accumulated data usage received from the second NF 300 in operation 322 .

[0137] NF 300 can enforce slicing policy based on information collected from other NFs 202 and 300.

[0138] Figure 4 is a diagram illustrating a registration procedure or a PDU session establishment procedure in a wireless communication system according to an embodiment of the present disclosure.

[0139] refer to Figure 4 , which illustrates the registration process of Example 2 or the PDU session establishment process of Example 3.

[0140] Example 2

[0141] Embodiment 2 describes a method of rejecting a registration request of an S-NSSAI when the current data rate / usage rate of the S-NSSAI exceeds the maximum data rate / usage rate in the 5G core network.

[0142] In the following, reference will be made to Figure 4 A registration process according to the second embodiment is described.

[0143] refer to Figure 4 , NF 302 of the 5G core network is an NF that manages the slice data rate / usage rate. For example, NF 302 may be NSSF, PCF, UDM, NWDAF, etc. AMF 401 is an NF that processes the terminal registration process.

[0144] refer to Figure 4 In operation 410, AMF 401 may send a slice event subscription request message to NF 302 to subscribe to events related to slices. The name of the message is exemplary, and various embodiments are not limited to the message name. The slice event subscription request message may include at least one of a slice ID (e.g., S-NSSAI) and an event ID. NF 302 may store the received slice event subscription request message.

[0145] At operation 326, according to Figure 3 According to the method described in the embodiment of the present invention, NF 302 can manage the data rate / usage rate of the slice associated with S-NSSAI. NF 302 can take specific actions while monitoring the current data rate / usage rate. In other words, NF 302 can enforce the policy.

[0146] For example, based on the slice policy information stored by NF 302, when the current data rate / usage rate of the slice exceeds the maximum data rate / usage rate, NF 302 may decide not to accept terminal registration anymore.

[0147] For example, NF 302 may decide to send a notification message to AMF 401 based on the subscription information included in the slice event message received from AMF 401 in operation 410 and stored by NF 302, and when the current data rate / usage rate of the slice satisfies the event condition.

[0148] In operation 412, the NF 302 may send a slice event notification message or a slice policy enforcement request message to the AMF 401. The names of the messages are exemplary, and various embodiments are not limited to the message names.

[0149] In the slice event notification message or slice policy enforcement request message sent from NF 302 to AMF 401, information about a slice ID (e.g., S-NSSAI), a current data rate / usage rate related to the slice, an event ID, at least one of the requested behaviors, and back-off timer information may be included. The event ID may be an indicator indicating which event is related to the slice. In addition, the event ID may be one of the event IDs received from AMF 401 in operation 410. The requested action may be an action that NF 302 requests AMF 401 to perform (e.g., terminal registration rejection, etc.). In addition, the requested action may not be included as a separate parameter in the message for operation 412, but may be implicitly indicated by the event ID.

[0150] AMF 401 may know the current data rate / usage rate information related to the slice based on the information received from NF 302. In addition, AMF 401 may determine an action related to the slice based on the information received from NF 302 (e.g., terminal registration rejection, etc.).

[0151] In operation 414, the terminal 400 may send a registration request message to the AMF 401. The registration request message may include a requested slice (requested NSSAI) to be used by the terminal 400. The requested slice may include a slice ID (eg, S-NSSAI) to be used by the terminal 400.

[0152] In operation 416, the AMF 401 may know that the data rate / usage rate of the slice (S-NSSAI) requested by the terminal 400 through the registration request message in operation 414 exceeds the maximum data rate / usage rate based on the information received through the slice event notification message or the slice policy enforcement request message in operation 412. Based on the determination that the data rate / usage rate of the requested slice (S-NSSAI) exceeds the maximum data rate / usage rate, the AMF 401 may decide to reject the slice (S-NSSAI) requested by the terminal 400 in operation 414.

[0153] AMF 401 may send a registration accept message to terminal 400. The registration accept message may include information indicating that the S-NSSAI has been rejected (eg, the rejected S-NSSAI includes the S-NSSAI). Terminal 400 may know that the S-NSSAI requested in operation 414 cannot be used.

[0154] Alternatively, the AMF 410 may send a registration reject message to the terminal 400. The terminal 400 may know that the registration requested in operation 414 has been rejected according to the reception of the registration reject message.

[0155] The registration accept message or the registration reject message may include backoff timer information. Terminal 400 may resend the registration request message requesting S-NSSAI after a time indicated by the backoff timer has passed or according to a local policy of terminal 400.

[0156] Example 3

[0157] Embodiment 3 describes a method for rejecting a PDU session request from an S-NSSAI when the NF of the 5G core network exceeds the maximum data rate / usage rate of the current data rate / usage rate of the S-NSSAI. According to various embodiments of the present disclosure, the AMF or SMF may reject the PDU session request.

[0158] In the following, reference will be made to Figure 4 Describe the PDU session establishment process according to embodiment 3. Specifically, refer to Figure 4 Describes the process where the AMF 401 rejects a PDU Session Request.

[0159] refer to Figure 4 , NF 302 of the 5G core network is an NF that manages the slice data rate / usage rate. For example, NF 302 may be NSSF, PCF, UDM, NWDAF, etc. AMF 401 is an NF that handles the PDU session establishment process.

[0160] refer to Figure 4In operation 410, AMF 401 may send a slice event subscription request message to NF 302 to subscribe to events related to slices. The name of the message is exemplary, and various embodiments are not limited to the message name. The slice event subscription request message may include at least one of a slice ID (e.g., S-NSSAI) and an event ID. NF 302 may store the received slice event subscription request message.

[0161] At operation 326, according to Figure 3 According to the method described in the embodiment of the present invention, NF 302 can manage the data rate / usage rate of the slice associated with S-NSSAI. NF 302 is currently monitoring the data rate / usage rate and can take specific actions. In other words, NF 302 can enforce the policy.

[0162] For example, based on the slice policy information stored by NF 302, when the current data rate / usage rate of the slice exceeds the maximum data rate / usage rate, NF 302 may decide not to accept PDU session establishment anymore.

[0163] Alternatively, for example, based on the subscription information included in the slice event message received from AMF 401 in operation 410 and stored by NF 302, NF 302 may determine to send a notification message to AMF 401 when the current data rate / usage rate of the slice satisfies the event condition.

[0164] In operation 412, NF 302 may send a slice event notification message or a slice policy enforcement request message to AMF 401. The names of the messages are exemplary, and various embodiments are not limited to the message names.

[0165] The slice event notification message or the slice policy enforcement request message sent from NF 302 to AMF 401 may include information about a slice ID (e.g., S-NSSAI), a current data rate / usage rate related to the slice, an event ID, at least one of a requested action, and backoff timer information. The event ID may be an indicator indicating which event is related to the slice. In addition, the event ID may be one of the event IDs received from AMF 401 in operation 410. The requested action may be an action that NF 302 requests AMF 401 to perform (e.g., rejection of PDU session establishment, etc.). In addition, the requested action may not be included as a separate parameter in the message of operation 412, but may be implicitly indicated by the event ID.

[0166] AMF 401 may know the current data rate / usage rate information related to the slice based on the information received from NF 302 through a slice event notification message or a slice policy enforcement request message. In addition, AMF 401 may determine the action related to the slice (e.g., rejection of PDU session establishment, etc.) based on the information received from NF 302.

[0167] At operation 414, the terminal 400 may send a PDU session establishment request message to the AMF 401. The PDU session establishment request message may include a requested slice (S-NSSAI) to be used by the terminal 400. The requested slice may include a slice ID (e.g., S-NSSAI) that the UE intends to use.

[0168] In operation 416, the AMF 401 may know that the data rate / usage rate of the slice (S-NSSAI) requested by the terminal 400 through the PDU session establishment request message in operation 414 exceeds the maximum data rate / usage rate based on the information received through the slice event notification message or the slice policy enforcement request message in operation 412. Based on the determination that the data rate / usage rate of the requested slice (S-NSSAI) exceeds the maximum data rate / usage rate, the AMF 401 may decide to reject the slice (S-NSSAI) requested by the terminal 400 in operation 414.

[0169] The AMF 401 may send a PDU session establishment reject message to the terminal 400. The PDU session establishment reject message may include information (eg, cause value, indication) indicating that the S-NSSAI has been rejected.

[0170] The terminal 400 may know that the PDU session cannot be established with the S-NSSAI requested in operation 414 according to the reception of the PDU session establishment rejection message. The PDU session establishment rejection message may include backoff timer information. The terminal 400 may resend the PDU session establishment request message requesting the S-NSSAI after the time indicated by the backoff timer has passed or according to the local policy of the terminal 400.

[0171] Figure 5 1 is a diagram illustrating a PDU session establishment process in a wireless communication system according to an embodiment of the present disclosure. Specifically, Figure 5 Figure 1 shows the method of rejecting a PDU session request through the SMF.

[0172] refer to Figure 5 , NF 302 of the 5G core network is an NF that manages slice data rate / usage rate. For example, NF 302 may be NSSF, PCF, UDM, NWDAF, etc. SMF 501 is an NF for managing sessions.

[0173] refer to Figure 5 In operation 510, SMF 501 may send a slice event subscription request message to NF 302 to subscribe to events related to slices. The name of the message is exemplary, and various embodiments are not limited to the message name. The slice event subscription request message may include at least one of a slice ID (e.g., S-NSSAI) and an event ID. NF 302 may store the received slice event subscription request message.

[0174] At operation 326, according to Figure 3 According to the method described in the embodiment of the present invention, NF 302 can manage the data rate / usage rate of the slice related to S-NSSAI. NF 302 can currently monitor the data rate / usage rate and can take specific actions. In other words, NF 202 can enforce the policy.

[0175] For example, based on the slice policy information stored by NF 302, when the current data rate / usage rate of the slice exceeds the maximum data rate / usage rate, NF 302 may decide not to accept PDU session establishment anymore.

[0176] Alternatively, for example, based on the subscription information included in the slice event message received from SMF 501 in operation 510 and stored by NF 302, NF 302 may determine to send a notification message to SMF 501 when the current data rate / usage rate of the slice satisfies the event condition.

[0177] In operation 512, the NF 302 may send a slice event notification message or a slice policy enforcement request message to the SMF 501. The names of the messages are exemplary, and various embodiments are not limited to the message names.

[0178] The slice event notification message or the slice policy enforcement request message sent from NF 302 to SMF 501 may include information about a slice ID (e.g., S-NSSAI), a current data rate / usage rate related to the slice, an event ID, at least one of a requested action, and backoff timer information. The event ID may be an indicator indicating which event is related to the slice. In addition, the event ID may be one of the event IDs received from SMF 501 in operation 510. The requested action may be an action that NF 302 requests SMF 501 to perform (e.g., rejection of PDU session establishment, etc.). In addition, the requested action may not be included as a separate parameter in the message of operation 512, but may be implicitly indicated by the event ID.

[0179] SMF 501 may know the current data rate / usage rate information related to the slice based on the information received from NF 302 through the slice event notification message or the slice policy enforcement request message. In addition, SMF 501 may determine the action related to the slice (e.g., rejection of PDU session establishment, etc.) based on the information received from NF 302.

[0180] At operation 514, the terminal 400 may send a PDU session establishment request message to the AMF 401. The PDU session establishment request message may include a requested slice (S-NSSAI) to be used by the terminal 400. The requested slice may include a slice ID (e.g., S-NSSAI) that the UE intends to use.

[0181] In operation 516 , the AMF 410 may send a Nsmf_PDUSession_CreateSMContext request message to the SMF 501 to transfer the PDU session establishment request message received from the terminal 400 to the SMF 501 .

[0182] In operation 518, the SMF 501 may know that the data rate / usage rate of the slice (S-NSSAI) requested by the terminal 400 received in operation 516 exceeds the maximum data rate / usage rate based on the information received through the slice event notification message or the slice policy enforcement request message in operation 512. Therefore, the SMF 501 may determine to reject the slice (S-NSSAI) requested by the terminal 400 received in operation 516.

[0183] The SMF 501 may send a PDU session establishment reject message to the terminal 400 via the AMF 401. The PDU session establishment reject message may be included in the Nsmf_PDUSession_CreateSMContext response message sent from the SMF 501 to the AMF 401. The PDU session establishment reject message may include information (e.g., cause value, indication) indicating that the S-NSSAI has been rejected. The PDU session establishment reject message may include backoff timer information.

[0184] In operation 520, the AMF 401 may send the PDU session establishment reject message received from the SMF 501 to the terminal 400. The terminal 400 may know that the PDU session using the S-NSSAI requested in operation 514 cannot be established. The terminal 400 may resend the PDU session establishment request message requesting the S-NSSAI after the time indicated by the backoff timer has passed or according to the local policy of the terminal 400.

[0185] Example 4

[0186] In Embodiment 4, a method of calculating a data rate is described so that when a current data rate / usage rate of an S-NSSAI exceeds a maximum data rate / usage rate, the data rate / usage rate of all PDU sessions established by an NF of a 5G core network through a corresponding S-NSSAI is reduced.

[0187] According to various embodiments of the present disclosure, when the current data rate / usage rate of the S-NSSAI exceeds the maximum data rate / usage rate, the NF of the 5G core network can reduce the data rate / usage rate of all PDU sessions established by the corresponding S-NSSAI. To this end, the NF can calculate the data rate / usage rate of the PDU session in various ways as follows.

[0188] The NF according to various embodiments may reduce the data rate / usage rate currently being used by each PDU session by using a percentage. For example, the NF may decide to reduce the data rate / usage rate currently being used by a specific value (e.g., 20%) according to an operator policy. According to this method, a PDU session using a 100 megabit per second (Mbps) data rate / usage rate and a PDU session using a 50 Mbps data rate / usage rate using S-NSSAI may reduce the data rate / usage rate to 80 Mbps and 40 Mbps, respectively.

[0189] The NF according to various embodiments may reduce the data rate / usage rate currently being used by each PDU session by using the data usage rate (bits per second, bps). For example, the NF may decide to reduce the currently used data rate / usage rate by a specific value (e.g., 20 Mbps) according to an operator policy. According to this method, a PDU session using a 100 Mbps data rate / usage rate and a PDU session using a 50 Mbps data rate / usage rate using S-NSSAI may reduce the data rate / usage rate to 80 Mbps and 30 Mbps, respectively.

[0190] The NF according to various embodiments may use a percentage to reduce the data rate / usage rate currently being used by all PDU sessions. For example, the NF may decide to reduce the total data rate / usage rate currently being used by a specific value (e.g., 20%) according to an operator policy. According to the method, if the total data rate / usage rate of all PDU sessions using S-NSSAI is one million Tbps, it may be decided to reduce the total data rate / usage rate of all PDU sessions by 20%, i.e., to 800,000 Tbps. Therefore, the NF may determine the value obtained by dividing the total data rate / usage rate of all reduced PDU sessions (e.g., 800,000 Tbps) by the number of total PDU sessions as the data rate / usage rate available for each PDU session. The NF may know the overall PDU session based on information received from other NFs (e.g., AMF, SMF, etc.).

[0191] The NF according to various embodiments may reduce the data rate / usage rate currently being used by all PDU sessions by using the data usage rate (bits per second). For example, the NF may decide to reduce the total data rate / usage rate currently being used by a specific value (e.g., 100,000 Tbps) according to an operator policy. According to the method, if the sum of the total data rate / usage rate of all PDU sessions using S-NSSAI is one million Tbps, it may be determined that the total data rate / usage rate of all PDU sessions is reduced to a value excluding the specific value (e.g., 100,000 Tbps), i.e., to 900,000 Tbps. Therefore, the NF may determine the value obtained by dividing the total data rate / usage rate of all reduced PDU sessions (e.g., 900,000 Tbps) by the number of all PDU sessions as the data rate / usage rate available for each PDU session. The NF may know the overall PDU session based on information received from other NFs (e.g., AMF, SMF, etc.).

[0192] According to various embodiments of the present disclosure, the data rate of a session determined by the NF through the method described in the fourth embodiment may include both data sent on a guaranteed bit rate (GBR) quality of service (QoS) flow and data sent on a non-GBR QoS flow.

[0193] For example, the data rate of the slice may include a guaranteed bit rate (GBR), a guaranteed flow bit rate (GFBR), a maximum bit rate (MBR), or a maximum flow bit rate (MFBR) for a GBR QoS flow. In addition, the data rate of the slice may include an aggregate maximum bit rate (AMBR) for a non-GBR QoS flow. The GBR or GFBR or MBR or MFBR or AMBR may be a value defined for a session or a value defined for a slice.

[0194] Alternatively, for example, the data rate of the slice may include a total maximum bit rate (TMBR) that includes both the data rate for GBR QoS flows and the data rate for non-GBR QoS flows, without distinguishing between the data rate for GBR QoS flows and the data rate for non-GBR QoS flows.

[0195] Therefore, the total slice data rate determined by the NF may include both data sent on the GBR QoS flow and data sent on the non-GBR QoS flow. The NF may use the value excluding the data rate sent on the GBR QoS flow from the total slice data rate as the data rate sent on the non-GBR QoS flow. For example, when the total slice data rate is 5000Mbps and the data rate sent on the GBR QoS flow is 3500Mbps, the data rate sent on the non-GBR QoS flow may be configured as 1500Mbps. The NF enforces the data rate limit of the GBR QoS flow to 3500Mbps among the received / determined slice data rate of 5000Mbps, and enforces the data rate limit of the non-GBR QoS flow to the remaining 1500Mbps.

[0196] If the total slice data rate needs to be reduced, the NF may preferentially reduce the data rate sent on the non-GBR QoS flow. For example, when the total slice data rate of 5000Mbps needs to be reduced to 4000Mbps, the NF may not change the data rate of 3500Mbps sent on the GBR QoS flow, and change the data rate sent on the non-GBR QoS flow from 1500Mbps to 500Mbps. The NF enforces the data rate limit of the GBR QoS flow to 3500Mbps among the received / determined slice data rate of 4000Mbps, and enforces the remaining 500Mbps by limiting the data rate of the non-GBR QoS flow.

[0197] According to various embodiments of the present disclosure, the data rate of the slice determined by the NF through the method described in the fourth embodiment may not include data sent on the GBR QoS flow, but only include data sent on the non-GBR QoS flow.

[0198] For example, the data rate of the slice determined by the NF may include GBR, GFBR, MBR or MFBR for GBR QoS flow. In addition, the data rate of the slice may include AMBR for non-GBR QoS flow. GBR, GFBR, MBR, MFBR or AMBR may be a value defined for a session, or a value defined for a slice.

[0199] Alternatively, for example, the data rate of the slice determined by the NF may include a total maximum bit rate (TMBR) that includes both the data rate for GBR QoS flows and the data rate for non-GBR QoS flows, without distinguishing between the data rate for GBR QoS flows and the data rate for non-GBR QoS flows.

[0200] Therefore, the NF may use a data rate based only on data sent on a non-GBR QoS flow, which is a data rate that excludes the data rate sent on a GBR QoS flow from a slice data rate that includes data sent on a GBR QoS flow and data sent on a non-GBR QoS flow.

[0201] To this end, when the total slice data rate is 5000 Mbps and the data rate sent on the GBR QoS flow is 3500 Mbps, the NF may configure the data rate sent on the non-GBR QoS flow to be 1500 Mbps. In this case, the slice data rate determined by the NF through the method described in Embodiment 4 may be 1500 Mbps. The NF enforces the received / determined 1500 Mbps to limit the data rate of the non-GBR QoS flow.

[0202] If the total slice data rate needs to be reduced, the NF may preferentially reduce the data rate sent on the non-GBR QoS flow. For example, when the total slice data rate of 5000Mbps needs to be reduced to 4000Mbps, the NF may change the data rate sent on the non-GBR QoS flow from 1500Mbps to 500Mbps without changing the data rate of 3500Mbps sent on the GBR QoS flow. In this case, the NF may use the changed data rate value, i.e., 500Mbps. The NF enforces the received / determined 500Mbps to limit the data rate of the non-GBR QoS flow.

[0203] Example 5

[0204] In Example 5, a method for reducing the data rate / usage rate of all PDU sessions established by the NF of the 5G core network using the corresponding S-NSSAI when the current data rate / usage rate of the S-NSSAI exceeds the maximum data rate / usage rate will be described.

[0205] Figure 6 is a diagram illustrating a PDU session modification procedure in a wireless communication system according to an embodiment of the present disclosure.

[0206] refer to Figure 6 , in operation 610, the terminal 400 may establish a PDU session using the S-NSSAI, and send and receive data using the PDU session.

[0207] At operation 326, NF 302 may pass Figure 3 The method described in the embodiment of 4 determines that the maximum data rate / usage rate of S-NSSAI has been exceeded. NF 302 can determine to reduce the data rate of all PDU sessions established using S-NSSAI based on the operator policy or the slice policy. In other words, NF 202 can enforce the policy. NF 302 can determine the data rate of the PDU session established using S-NSSAI by the method described in Example 4. The data rate of the PDU session determined by NF 302 in operation 326 (hereinafter referred to as the "new slice data rate") can be a value lower than the data rate currently used by the PDU session (hereinafter referred to as the "old slice data rate").

[0208] According to various embodiments of the present disclosure, one of operations 612a, 612b, or 612c may be performed.

[0209] Operation 612a consists of operations 612a-1 and 612a-2. In operation 612a-1, NF 302 may send a slice event notification or a slice policy enforcement request message to PCF 600. The name of the message is exemplary, and various embodiments are not limited to the message name. In the slice event notification or slice policy enforcement request message of operation 612a-1, information about at least one of the S-NSSAI and the new slice data rate of the PDU session associated with the S-NSSAI determined by NF 302 in operation 326 may be included.

[0210] At operation 612a-2, PCF 600 may determine that QoS modification of the PDU session associated with the S-NSSAI is required based on the information received from NF 302. PCF 600 may perform an SM policy association modification (Session Management (SM) Policy Association Modification) procedure with SMF 501 that manages the PDU session associated with the S-NSSAI. Through the SM policy association modification procedure, PCF 600 may send a new slice data rate of the PDU session associated with the S-NSSAI to SMF 501.

[0211] When SMF 501 manages one or more PDU sessions associated with S-NSSAI, PCF 600 can perform a single SM policy association modification process with SMF 501, and SMF 501 applies the new slice data rate obtained in the SM policy association modification process to all PDU sessions associated with S-NSSAI.

[0212] Alternatively, when SMF 501 is managing one or more PDU sessions linked to S-NSSAI, PCF 600 may perform as many SM policy association modification processes with SMF 501 as the number of PDU sessions, and SMF 501 applies the new slice data rate obtained in the SM policy association modification process to each PDU session associated with the S-NSSAI.

[0213] At operation 612b, NF 302 may send a slice event notification message or a slice policy enforcement request message to SMF 501 that manages the PDU session associated with S-NSSAI. The name of the message is exemplary, and various embodiments are not limited to the message name. In the slice event notification or slice policy enforcement request message of operation 612b, information about at least one of the new slice data rates of the PDU session associated with S-NSSAI determined by NF 302 at operation 326 may be included.

[0214] When SMF 501 manages one or more PDU sessions linked to S-NSSAI, NF 302 may send a single message to SMF 501, and SMF 501 may apply the new slice data rate obtained from NF 302 to all PDU sessions associated with the S-NSSAI.

[0215] Alternatively, when SMF 501 manages one or more PDU sessions associated with an S-NSSAI, NF 302 may send as many messages as the number of PDU sessions to SMF 501, and SMF 501 may apply the new slice data rate obtained from NF 302 to each PDU session associated with the S-NSSAI.

[0216] At operation 612c, the UDM may determine that a QoS modification of the PDU session associated with the S-NSSAI is required. The UDM may send a Nudm_SDM_Notification message to the SMF 501 that manages the PDU session associated with the S-NSSAI. The Nudm_SDM_Notification message may include a new slice data rate for the PDU session associated with the S-NSSAI.

[0217] When SMF 501 manages one or more PDU Sessions linked to S-NSSAI, UDM may send a message to SMF 501, and SMF 501 may apply the new slice data rate obtained from UDM to all PDU Sessions associated with S-NSSAI.

[0218] Alternatively, when SMF 501 manages one or more PDU sessions associated with an S-NSSAI, UDM may send as many messages as the number of PDU sessions to SMF 501, and SMF 501 may apply the new slice data rate obtained from UDM to each PDU session associated with the S-NSSAI.

[0219] When determining at operation 612c that the UDM needs to modify the QoS of the PDU session associated with the S-NSSAI, the UDM may be based on information received from NF 302. The UDM may receive from NF 302 a new slice data rate for the PDU session associated with the S-NSSAI determined by NF 302.

[0220] In operation 614, the SMF 501 may determine that a QoS update of a PDU session associated with the S-NSSAI is required based on the information received in operation 612a (operations 612a-1 and 612a-2), operation 612b, or operation 612c.

[0221] SMF 501 can determine the coverage of QoS update (e.g., uplink data rate and downlink data rate) based on at least one of operator policy, local policy, subscription information obtained from UDM, policy information obtained from PCF, and information received from NF 302.

[0222] For example, when the QoS update is applied to the downlink data rate, operations 616, 618, 620, 622, and 624 may be omitted. In this case, the new slice data rate may be transmitted to the UPF. Alternatively, when the QoS update is applied to the downlink data rate, operation 620 may be omitted. In this case, the new slice data rate may be sent to the UPF and the base station.

[0223] For example, when the QoS update is applied to the uplink data rate, operations 626 and 628 may be omitted. In this case, the new slice data rate may be sent to the terminal and the base station. Alternatively, when the QoS update is applied to the uplink data rate, operations 620, 626, and 628 may be omitted. In this case, the new slice data rate may be sent to the base station. Alternatively, when the QoS update is applied to the uplink data rate, operations 620, 626, and 628 may be omitted. In this case, the new slice data rate may be sent to the base station. Figure 6 In this case, the new slice data rate can be sent to the terminal, base station and UPF.

[0224] In operation 616, the SMF 501 may send a Namf_Communication_N1N2MessageTransfer message or a Nsmf_PDUSession_SMContextStatusNotify message to the AMF 401. The name of the message is exemplary, and various embodiments are not limited to the message name. In the message of operation 616, S-NSSAI, PDU session ID, SM context ID, bulk request indicator, and data rate (new slice data rate) may be included.

[0225] The PDU Session ID may include the IDs of all PDU sessions established in association with the S-NSSAI through the AMF 401. The SM Context ID may include the SM Context ID associated with all PDU sessions established in association with the S-NSSAI through the AMF 401. In this case, the SMF 501 may send a message to the AMF 401 to update the data rates of all PDU sessions associated with the S-NSSAI.

[0226] The PDU Session ID may include one PDU Session ID established in association with the S-NSSAI through the AMF 401. The SM Context ID may include one SM Context ID established in association with the S-NSSAI through the AMF 401. In this case, the SMF 501 may send as many messages as the number of PDU sessions to the AMF 401 to update the data rate of each PDU session associated with the S-NSSAI.

[0227] If the message at operation 616 does not include a session ID or an SM context ID, the AMF 401 may apply the received data rate to all PDU sessions associated with the S-NSSAI.

[0228] The AMF 401 may apply the received data rate to one PDU session associated with the S-NSSAI or to all PDU sessions associated with the S-NSSAI. For example, the AMF 401 may determine the data rate coverage (e.g., one PDU session or all PDU sessions) based on the message (e.g., message name, message type, etc.) received at operation 616. Alternatively, for example, when the message of operation 616 includes a batch request indicator, or when the message of operation 616 does not include a PDU session ID or an SM context ID, the AMF 401 may apply the received data rate to all PDU sessions associated with the S-NSSAI.

[0229] At operation 618, the AMF 401 may send an N2 session request message to the base station 500. The name of the message is exemplary, and various embodiments are not limited to the message name. The message of operation 618 may include at least one of S-NSSAI, PDU session ID, batch request indicator, and new slice data rate.

[0230] The PDU session ID may include the IDs of all PDU sessions established in association with the S-NSSAI through the base station 500. In this case, the AMF 401 may send one message to the base station 500 to update the data rates of all PDU sessions associated with the S-NSSAI.

[0231] The PDU session ID may include one PDU session ID established in association with the S-NSSAI by the base station 500. In this case, the AMF 401 may send as many messages as the number of PDU sessions to the base station 500 to update the data rate of each PDU session associated with the S-NSSAI.

[0232] When the PDU session ID is not included in the message of operation 618, the base station 500 may apply the received data rate to all PDU sessions associated with the S-NSSAI.

[0233] When the batch request indicator is included in the message of operation 618, the base station 500 may apply the received data rate to all PDU sessions associated with the S-NSSAI.

[0234] The base station 500 may adjust the uplink data rate and / or downlink data rate of the PDU session, data bearer, or QoS flow associated with the S-NSSAI based on the received information.

[0235] At operation 620, the base station 500 may perform an AN-specific resource modification procedure with the terminal 400. During the AN-specific resource modification (Access Node (AN) Specific Resource Modification) procedure, the base station 500 may send a PDU Session Modification Command message to the terminal 400. The PDU Session Modification Command message may include at least one of an S-NSSAI, a PDU session ID, and a new slice data rate.

[0236] Terminal 400 may adjust the uplink data rate of the PDU session associated with the S-NSSAI based on the received information.

[0237] In operation 622, the base station 500 may send an N2 session response message to the AMF 401.

[0238] In operation 624, AMF 401 may send a Nsmf_PDUSession_UpdateSMContext request (Nsmf_PDUSession_UpdateSMContext request) message to SMF 501. Upon receiving the Nsmf_PDUSession_UpdateSMContext request (Nsmf_PDUSession_UpdateSMContext request) message in operation 624, SMF 501 may know that the base station and / or terminal has adjusted the data rate of the PDU session associated with the S-NSSAI.

[0239] At operation 626, the SMF 501 may send an N4 session modification request message to the UPF 502 that is providing the PDU session associated with the S-NSSAI. The name of the message is exemplary, and various embodiments of the present disclosure are not limited to the message name. In the N4 session modification request message of operation 626, information about at least one of the S-NSSAI, the PDU session ID, the N4 session ID, the bulk request indicator, and the new slice data rate may be included.

[0240] The PDU session ID may include IDs of all PDU sessions established in association with the S-NSSAI through the UPF 502. The N4 session ID may include N4 session IDs associated with all PDU sessions established in association with the S-NSSAI through the UPF 502. In this case, the SMF 501 may send a message to the UPF 502 to update the data rates of all PDU sessions associated with the S-NSSAI.

[0241] The PDU session ID may include one PDU session ID established in association with the S-NSSAI by the UPF 502. The N4 session ID may include one SM context ID established in association with the S-NSSAI by the UPF 502. In this case, the SMF 501 may send a message equal to the number of PDU sessions or N4 sessions to the UPF 502 to update the data rate of each PDU session associated with the S-NSSAI.

[0242] When the PDU session ID or the N4 session ID is not included in the message of operation 626, the UPF 502 may apply the received data rate to all PDU sessions associated with the S-NSSAI.

[0243] When the batch request indicator is included in the message of operation 626, the UPF 502 may apply the received data rate to all PDU sessions associated with the S-NSSAI.

[0244] At operation 628, UPF 502 may adjust the downlink data rate and / or uplink data rate of the PDU session associated with the S-NSSAI based on the received information. After adjusting the downlink data rate and / or uplink data rate of the PDU session associated with the S-NSSAI, UPF 502 may send an N4 session modification response message to SMF 501.

[0245] When there are multiple UPFs providing PDU sessions linked to the S-NSSAI, the SMF 501 may perform operation 626 or operation 628 with each UPF.

[0246] Figure 7 is a flowchart illustrating an operation process of a network function in a wireless communication system according to an embodiment of the present disclosure.

[0247] refer to Figure 7 NF 302 is a NF that manages the slice data rate / usage rate. For example, NF 302 may be NSSF, PCF, UDM, NWDAF, etc.

[0248] At operation 701, NF 302 may obtain slice policy information. For example, NF 302 may receive slice policy information configuration through operation, administration and maintenance (OAM). Alternatively, NF 302 may receive slice policy information from another NF or AF. The slice policy information may include maximum data rate information.

[0249] In operation 702, NF 302 may monitor a current data rate of a PDU session associated with a slice. For example, NF 302 may receive a current data rate of a PDU session associated with a slice from a base station or another NF.

[0250] In operation 703, NF 302 may compare the maximum data rate included in the slice policy information with the sum of the data rates used in all PDU sessions associated with the slice. Specifically, NF 302 may determine whether the sum of the data rates being used in the PDU sessions associated with the slice exceeds the maximum data rate.

[0251] If the sum of data rates being used in all PDU sessions associated with the slice exceeds the maximum data rate included in the slice policy information, NF 302 may perform operation 704.

[0252] If the sum of data rates being used in all PDU sessions associated with the slice does not exceed the maximum data rate included in the slice policy information, NF 302 may perform operation 702.

[0253] At operation 704, NF 302 may calculate a data rate that may be used by a PDU session associated with the slice.

[0254] In operation 705, NF 302 may send a data rate calculated by NF 302 that may be used by a PDU session associated with the slice to another NF.

[0255] The methods disclosed in the claims and / or the methods according to the various embodiments described in the specification of the present disclosure may be implemented by hardware, software, or a combination of hardware and software.

[0256] When the method is implemented by software, a computer-readable storage medium for storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors in an electronic device. At least one program may include instructions that cause the electronic device to perform the method according to various embodiments of the present disclosure as defined in the appended claims and / or disclosed herein.

[0257] Programs (software modules or software) may be stored in non-volatile memory, including random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magnetic disk storage, compact disk ROM (CD-ROM), digital versatile disk (DVD) or other types of optical storage devices or tape cassettes. Alternatively, any combination of some or all of them may form the memory in which the program is stored. In addition, a plurality of such memories may be included in the electronic device.

[0258] In addition, the program can be stored in an attachable storage device that can access the electronic device through a communication network, such as the Internet, an intranet, a local area network (LAN), a wireless LAN (WLAN), and a storage area network (SAN), or a combination thereof. Such a storage device can access the electronic device via an external port. In addition, a separate storage device on the communication network can access the portable electronic device.

[0259] In the specific embodiments of the present disclosure described above, the elements included in the present disclosure are expressed in the singular or plural according to the specific embodiments presented. However, for the convenience of description, the singular form or plural form is appropriately selected for the presented situation, and the present disclosure is not limited by the elements expressed in the singular or plural. Therefore, any element expressed in the plural may also include a single element or an element expressed in the singular may also include multiple elements.

[0260] While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims and their equivalents.

Claims

1. A method for operating a policy control function (PCF) in a wireless communication system, the method comprising: Obtaining network slice related policy information, the network slice related policy information including a maximum data rate of a network slice of a single network slice selection auxiliary information (S-NSSAI), wherein the maximum data rate includes a maximum bit rate (MBR) of a guaranteed bit rate (GBR) quality of service (QoS) flow and an aggregate maximum bit rate (AMBR) of a non-guaranteed bit rate (non-GBR) QoS flow; monitoring a data rate associated with the network slice; determining whether the data rate associated with the network slice exceeds the maximum data rate; and Upon determining that the data rate associated with the network slice exceeds the maximum data rate, changing the AMBR of the non-GBR QoS flow so as not to exceed the maximum data rate.

2. The method according to claim 1, further comprising An event notification message of the network slice including the changed AMBR is sent to the Session Management Function (SMF).

3. The method according to claim 2, further comprising: In case it is determined that the data rate associated with the network slice exceeds the maximum data rate, an event notification message of the network slice including the data rate associated with the network slice is sent to the SMF.

4. The method according to claim 1, wherein: Upon determining that the data rate associated with the network slice exceeds the maximum data rate, rejecting the request for new protocol data unit (PDU) session establishment.

5. The method according to claim 1, wherein: The data rate associated with the network slice is the sum of the data rates of all protocol data unit (PDU) sessions associated with the network slice.

6. The method according to claim 2, wherein: The event notification message of the network slice also includes at least one of: a cause value or indication associated with a refusal to establish a PDU session associated with the network slice, a cause value or indication associated with a refusal to register a user device requesting the network slice, and the S-NSSAI of the network slice.

7. A policy control function (PCF) device in a wireless communication system, the PCF device comprising: Transceiver; as well as At least one processor configured to: Obtaining network slice related policy information, the network slice related policy information including a maximum data rate of a network slice of a single network slice selection auxiliary information (S-NSSAI), wherein the maximum data rate includes a maximum bit rate MBR of a guaranteed bit rate (GBR) quality of service (QoS) flow and an aggregate maximum bit rate (AMBR) of a non-guaranteed bit rate (non-GBR) QoS flow; monitoring a data rate associated with the network slice; determining whether the data rate associated with the network slice exceeds the maximum data rate; and Upon determining that the data rate associated with the network slice exceeds the maximum data rate, changing the AMBR of the non-GBR QoS flow so as not to exceed the maximum data rate.

8. The PCF device according to claim 7, wherein: The at least one processor is further configured to: An event notification message of the network slice including the changed AMBR is sent to the Session Management Function (SMF).

9. The PCF device according to claim 8, wherein: The at least one processor is further configured to: In case it is determined that the data rate associated with the network slice exceeds the maximum data rate, an event notification message of the network slice including the data rate associated with the network slice is sent to the SMF.

10. The PCF device according to claim 7, wherein: In an event that it is determined that the data rate associated with the network slice exceeds the maximum data rate, a request for new protocol data unit (PDU) session establishment is rejected.

11. The PCF device according to claim 7, wherein: The data rate associated with the network slice is the sum of the data rates of all protocol data unit (PDU) sessions associated with the network slice.

12. The PCF device according to claim 8, wherein: The event notification message of the network slice also includes at least one of: a cause value or indication associated with a refusal to establish a PDU session associated with the network slice, a cause value or indication associated with a refusal to register a user device requesting the network slice, and the S-NSSAI of the network slice.

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