KR20210034453A - Method and apparatus for controlling data rate in wireless communication system - Google Patents

Abstract

Disclosed are a method for controlling a rate of data transmitted from/received to a terminal in a wireless communication system to efficiently manage network resources and an apparatus thereof. According to one embodiment of the present invention, a method for controlling a data rate in an access and mobility management function (AMF) apparatus of a wireless communication system comprises the following operations: receiving a registration request message including an identifier of a terminal from the terminal; transmitting the registration request message including the identifier of the terminal to an unified data management (UDM) apparatus; receiving subscription information including network slice information allocable to the terminal from the UDM apparatus; inquiring a policy linkage of the terminal including the network slice information to a policy control function (PCF) apparatus; receiving a policy association response message including total rate limit information of a serving network slice from the PCF apparatus; and providing the total rate limitation information of the serving network slice to a base station of the terminal.

Description

Data rate control method and device in wireless communication system {METHOD AND APPARATUS FOR CONTROLLING DATA RATE IN WIRELESS COMMUNICATION SYSTEM}

The present disclosure discloses a method and apparatus for controlling the speed of data transmitted/received by a terminal in a wireless communication system.

Efforts are being made to develop an improved 5G communication system or a pre-5G communication system in order to meet the increasing demand for wireless data traffic after the commercialization of 4G communication systems. For this reason, the 5G communication system or the pre-5G communication system is called a communication system after a 4G network (Beyond 4G Network) or a system after an LTE system (Post LTE).

In order to achieve a high data rate, 5G communication systems are being considered for implementation in an ultra-high frequency (mmWave) band (eg, such as a 60 gigabyte (60 GHz) band). In order to mitigate the path loss of radio waves in the ultra-high frequency band and increase the transmission distance of radio waves, 5G communication systems include beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO). ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed.

In addition, in order to improve the network of the system, in 5G communication systems, evolved small cells, advanced small cells, cloud radio access networks (cloud RAN), and ultra-dense networks. , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation And other technologies are being developed.

In addition, in 5G systems, advanced coding modulation (ACM) methods such as Hybrid FSK and QAM Modulation (FQAM) and SWSC (Sliding Window Superposition Coding), advanced access technologies such as Filter Bank Multi Carrier (FBMC), NOMA (non orthogonal multiple access), and sparse code multiple access (SCMA) have been developed.

With the development of various IT (information technology) technologies, network equipment has evolved into a virtualized network function (NF) by applying virtualization technology. It can be installed/operated in various types of clouds or data centers (DC) by being implemented in software form out of restrictions. In particular, the NF can be freely expanded or scaled, installed (initiation), or terminated according to service requirements, system capacity, and network load. It should be noted that even if these NFs are implemented in the form of software, they are not excluded from the physical configuration, since they must be driven on a physical configuration, for example, a predetermined device. In addition, NFs can be implemented only with simple physical configuration, that is, hardware.

In order to support various services in these various network structures, network slicing technology has been introduced. Network slicing is a technology that logically composes a network as a set of network functions (NF) to support a specific service and separates it from other slices. One terminal can access two or more slices when receiving various services.

With the development of such a mobile communication system, various services can be provided, and thus, a method for effectively controlling a communication speed of a terminal is required.

In the present disclosure, it is intended to provide a method and apparatus capable of effectively controlling a data rate in a wireless communication system.

A method according to an embodiment of the present disclosure is a data rate control method of a terminal in an access and mobility management function (AMF) device of a wireless communication system, and a registration request including an identifier of the terminal from the terminal Receiving a message; Transmitting a registration request message including the identifier of the terminal through Unified Data Management (UDM); Receiving subscription information including network slice information that can be allocated to the terminal from the UDM; Inquiring for policy association of the terminal including the network slice information to a Policy Control Function (PCF) device; Receiving a policy association response message including total transmission rate limitation information of a serving network slice from the PCF; And providing information on limiting the total transmission rate of the serving network slice to the base station of the terminal.

Using the method and apparatus according to the present disclosure, it is possible to effectively control the data rate in a wireless communication system. In addition, when the embodiment of the present disclosure is applied, the mobile communication system can efficiently manage network resources by configuring a network slice to provide a required data rate. In addition, the mobile communication system can change the data rate of the slice to which the terminal subscribes according to various circumstances.

1 illustrates a registration procedure according to an embodiment of the present disclosure.
2 illustrates a PDU Session Establishment procedure according to an embodiment of the present disclosure.
3A and 3B illustrate a PDU Session Establishment procedure according to an embodiment of the present disclosure.
4A and 4B illustrate a PDU Session Establishment procedure according to an embodiment of the present disclosure.
5A and 5B illustrate a PDU Session Establishment procedure according to an embodiment of the present disclosure.
6 illustrates a service request procedure according to an embodiment of the present disclosure.
7 illustrates a UE Configuration Update procedure according to an embodiment of the present disclosure.
8 is an internal functional block diagram of an NF according to various embodiments of the present disclosure.
9 is a block diagram of an internal function of a terminal according to various embodiments of the present disclosure.
10 illustrates a PDU session establishment procedure according to various embodiments of the present disclosure.

Terms used in the present disclosure are only used to describe a specific embodiment, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person of ordinary skill in the technical field described in the present disclosure. Among the terms used in the present disclosure, terms defined in a general dictionary may be interpreted as having the same or similar meanings as those in the context of the related technology, and unless explicitly defined in the present disclosure, an ideal or excessively formal meaning Is not interpreted as. In some cases, even terms defined in the present disclosure cannot be interpreted to exclude embodiments of the present disclosure.

In various embodiments of the present disclosure described below, a hardware approach is described as an example. However, since various embodiments of the present disclosure include technology using both hardware and software, various embodiments of the present disclosure do not exclude a software-based approach.

Hereinafter, the present disclosure relates to a method and apparatus for supporting various services in a wireless communication system. Specifically, the present disclosure describes a technology for supporting various services by supporting mobility of a terminal in a wireless communication system.

A term for identifying an access node used in the following description, a term for a network entity or a network function (NF), a term for messages, and an interface between network objects. Terms, terms referring to various types of identification information, and the like are exemplified for convenience of description. Accordingly, the present disclosure is not limited to terms described later, and other terms referring to objects having an equivalent technical meaning may be used.

In addition, NFs used in the present disclosure may be one network object or part of one network object. These network objects can have both a physical configuration and a software configuration, and can be implemented as one device, one device, and one computing system. Accordingly, hereinafter, each NF may be understood as including a physical device and a software configuration implemented as one network object or a part of one network object, unless otherwise described.

For convenience of description below, terms and names defined in 3GPP 3rd generation partnership project long term evolution (LTE) and 5G standards are used in this disclosure. However, the present disclosure is not limited by the terms and names, and may be equally applied to systems conforming to other standards.

A 5G system according to an embodiment of the present disclosure may be composed of a terminal, a base station, and a 5G core network. The 5G Core Network can be composed of network functions such as AMF, SMF, PCF, UPF, UDM, UDR, NEF, and NSSF (Network Function, hereinafter used together with NF). According to an embodiment of the present disclosure, a network function (NF) may mean a network entity (a network entity, hereinafter used together with NE) and a network resource. NG-RAN (Next Generation-Radio Access Network, hereinafter 5G-RAN, mixed with RAN) refers to a base station that provides a wireless communication function to a terminal. The terminal (User Equipment, Terminal, UE) can access the 5G core network through the base station.

In addition, various network functions described below may be composed of one specific physical device or two or more physical devices. In addition, each of the physical devices may include a program (software) for executing the methods described below under the control of a processor included therein. In the following description, only the names of each NF are presented for convenience of explanation, but as described above, it is implemented as a physical device including at least one processor, and a program (software) for the operation described in the present disclosure is mounted. It is obvious to those skilled in the art that it can be (mounted). Therefore, the expression "device" will be omitted below, and will be described only with the name of a specific NF.

According to an embodiment of the present disclosure, an Access and Mobility management function (AMF) is a network function that manages wireless network access and mobility for a terminal. SMF (Session Management Function) is a network function that manages the packet data network connection provided to the terminal. Packet Data Network connection is referred to as a PDU (Protocol Data Unit) Session. The PDU session information may include quality of service (QoS) information, billing information, or packet processing information. The Policy Control Function (PCF) is a network function that applies the service policy of the mobile communication service provider to the terminal, the billing policy, and the policy for PDU session. UPF (User Plane Function) serves as a gateway for transmitting packets transmitted and received by the terminal, and is a network function controlled by SMF. The UPF is connected to a Data Network (DN) and serves to transmit an uplink data packet generated by a terminal to an external data network through a 5G system. In addition, the UPF serves to deliver a downlink data packet generated and received in an external data network to a terminal through a 5G system. For example, the UPF is connected to a data network connected to the Internet, and can route data packets sent from the terminal to the Internet, and can route data packets sent from the Internet to the terminal.

Unified Data Management (UDM) is a network function that stores and manages subscriber information. Network Exposure Function (NEF) allows access to terminal management information in a 5G network, subscription to terminal mobility management events, subscription to terminal session management events, and sessions. Connected to 5G core network NFs, such as requesting related information, setting charging information of the terminal, and requesting to change the PDU session policy for the terminal, and transmitting information about the terminal to the NFs or information about the terminal. It is a network function that performs the role of reporting data to the outside. AF (Application Function) is a network function that can use the services and functions provided by the 5G network through NEF.

The Unified Data Repository (UDR) is a network function that stores and manages data. For example, the UDR may store terminal subscription information and provide terminal subscription information to the UDM. The UDR can store the operator policy information and provide the operator policy information to the PCF. UDR may store network service exposure-related information and provide network service exposure-related information to NEF. The Network Slice Selection Function (NSSF) is a network function that determines a network slice available to a terminal and determines a network slice instance constituting such a network slice.

Each NF defines the services they provide, and the services provided by NF can be referred to as Npcf, Nsmf, Namf, and Nnef services. For example, when the AMF delivers a session-related message to the SMF, the AMF can use a service (or API) called Nsmf_PDUSession_CreateSMContext.

In the following description, one service, for example, the Npcf service may collectively refer to messages that can be exchanged with the PCF by using an interface for communicating with the PCF. In the above example, when the AMF delivers a session-related message to the SMF, the AMF is an interface for communicating with the SMF when using a service called Nsmf_PDUSession_CreateSMContext, and may mean a specific message configured according to the format required by the SMF.

The terminal accesses the AMF through the base station and can exchange control plane signaling messages with the 5G core network. In addition, the terminal may access the UPF through the base station and exchange data with the data network and user plane data. The application server that provides the application layer service to the terminal may be referred to as AF when exchanging control plane signaling messages with the 5G core network, and may be referred to as DN when exchanging user plane data with the terminal. . Accordingly, AF and DN can be used interchangeably as a name that refers to the application server.

Meanwhile, the mobile communication system may be configured as a network supporting network slicing. That is, one network can be physically configured and managed as a logically separated network slice (hereinafter, used together with a slice). A mobile communication service provider can provide a dedicated network slice specialized for the service for various services having different characteristics. Each network slice may have different types and amounts of resources required according to service characteristics, and the mobile communication system can guarantee the resources required by each network slice. For example, a network slice providing a voice telephony service may have a high frequency of control plane signaling, and a network slice may be configured with a specialized NF. A network slice providing an Internet data service may have a high frequency of generating large-capacity data traffic, and a network slice may be configured with a specialized NF. In the 5G system defined by 3GPP, one network slice may be referred to as “S-NSSAI”. Single Network Slice Selection Assistance Information (S-NSSAI) may be composed of a Slice/Service Type (SST) value and a Slice Differentiator (SD) value. SST represents the characteristics of services supported by the slice (e.g., enhanced Mobile BroadBand (eMBB), Internet of Things (IoT)), Ultra-Reliable Low Latency Communications (URLLC), Vehicle-to-Everything (V2X), etc. I can. SD can be used as an additional identifier for a specific service referred to as SST.

The terminal may access the mobile communication system and perform a registration procedure. During the registration procedure, the terminal may transmit information on a network slice to be used to the mobile communication system. This network slice information transmitted by the terminal to the mobile communication system may be referred to as a “requested slice (Requested NSSAI)”, and the Requested NSSAI may include one or more S-NSSAI values. The mobile communication system may authenticate the request of the terminal and, if the authentication is successful, determine network slice information that can be used by the terminal. This network slice information determined by the mobile communication system may be referred to as “Allowed NSSAI”, and the Allowed NSSAI may include one or more S-NSSAI values. The terminal can receive the Allowed NSSAI from the mobile communication system. The terminal stores the Allowed NSSAI and can use it in a later procedure.

The terminal having completed the registration procedure may perform a PDU Session Establishment procedure in order to transmit and receive data by being connected to the DN. The terminal may include S-NSSAI and/or DNN information to be used in a PDU session establishment request message and transmit it to the mobile communication system. The mobile communication system can authenticate the request of the terminal and, if the authentication is successful, establish a PDU session for the terminal. Through this process, the UE may establish one or more PDU sessions in one network slice. When different PDU sessions are supported by one terminal in one network slice, the DNNs may be the same or different. For example, the UE may establish three different PDU sessions using an eMBB slice (eMBB S-NSSAI). The first PDU session can support eMBB S-NSSAI and DNN 1. The second PDU session can support eMBB S-NSSAI and DNN 2. The third PDU session can support eMBB S-NSSAI and DNN 2. When the first PDU session and the second PDU session support different DNNs in the same network slice (S-NSSAI), the second PDU session and the third PDU session support the same DNN in the same network slice. It may correspond to.

In the present disclosure, a method and apparatus for controlling a data rate of a network slice for each terminal by a mobile communication system will be described. To this end, in the present disclosure, operations of nodes constituting a 5G system for controlling a data rate of a network slice for each terminal, for example, a terminal, a base station, AMF, SMF, and UPF, will be described. In particular, when one S-NSSAI supports two or more PDU sessions with one terminal, a method and apparatus for controlling uplink data traffic and downlink data traffic of each PDU session will be described.

When the embodiment of the present disclosure is applied, the mobile communication system can efficiently manage network resources by configuring a network slice to provide a required data rate. In addition, the mobile communication system can change the data rate of the slice to which the terminal subscribes according to various circumstances.

According to various embodiments of the present disclosure, in describing nodes constituting a 5G system hereinafter, a number may be assigned. For example, when a number is assigned, such as SMF1 and SMF2, each number may mean that the SMF is logically and/or physically separated, and the performed operation may be the same. Assigning a number as described above may mean that a plurality of sessions are logically and/or physically processed in different NFs.

In the following description, NF is, for example, an access and mobility management function (Access and Mobility Management Function, hereinafter referred to as AMF) device, a session management function (Session Management Function, hereinafter referred to as SMF) device, and a network slice selection function device ( Network slice selection function, NSSF) may be at least one of the device. However, the embodiments of the present disclosure may be equally applied even when NF is actually implemented as an instance (Instance, respectively AMF Instance, SMF Instance, NSSF Instance, etc.).

In the present disclosure, Instance is a specific NF exists in the form of a software code, and a physical computing system, for example, a physical or/and logical from a computing system in order to perform the function of NF in a specific computing system existing on the core network. It can mean a state in which a resource is allocated and can be executed. Therefore, AMF Instance, SMF Instance, and NSSF Instance may mean that physical or/and logical resources can be allocated and used for AMF, SMF, and NSSF operations from a specific computing system existing on the core network, respectively. As a result, when a physical AMF, SMF, NSSF device exists, and AMF Instance, SMF Instance, which are allocated and used physical or/and logical resources for AMF, SMF, NSSF operation from a specific computing system existing on the network, NSSF Instance can perform the same operation. Therefore, in an embodiment of the present invention, the matter described as NF (AMF, SMF, UPF, NSSF, NRF, SCP, etc.) may be replaced with an NF instance or, conversely, a matter described as an NF instance may be replaced with NF. Likewise, in an embodiment of the present invention, a matter described as an NW slice may be replaced with an NW slice instance or, conversely, a matter described as an NW slice instance may be replaced with an NW slice.

[Example 1]

Embodiment 1 of various embodiments of the present disclosure describes a method of managing a data rate of a network slice for each terminal in a mobile communication system. More specifically, in Example 1, the data rate information of the network slice for each terminal is defined, and the terminal, the base station, and the NF store network slice data rate information for each terminal, and control uplink data and downlink data traffic. Describe the method.

According to an embodiment of the present disclosure, an aggregate rate limit QoS parameter associated with S-NSSAI may be defined in association with a network slice used by a terminal. As such, an example of the total rate limiting QoS parameter linked to the network slice, per S-NSSAI Aggregate Maximum Bit Rate per network slice, hereinafter, Slice-AMBR or S-NSSAI-AMBR or NSSAI-AMBR or SST-AMBR or It may be mixed with S-AMBR). Slice-AMBR can be classified into subscribed Slice-AMBR, serving network Slice-AMBR, authorized Slice-AMBR, etc. according to the NF that stores and manages Slice-AMBR.

Subscribed Slice-AMBR may be stored in UDM as UE subscription information. UDM can provide subscribed Slice-AMBR to 5G core network NF (eg, AMF, SMF, etc.). The UDM may manage the subscribed Slice-AMBR together with the subscribed S-NSSAI of the terminal. For example, when there is eMBB S-NSSAI, URLLC S-NSSAI, IoT S-NSSAI as the terminal subscription slice, there may be Slice-AMBR linked to each S-NSSAI. That is, for example, there may be eMBB Slice-AMBR, URLLC Slice-AMBR, and IoT Slice-AMBR. In addition, when there is no Slice-AMBR linked to a specific S-NSSAI, there may be a default Slice-AMBR that can be applied. That is, for example, if there is no IoT Slice-AMBR, the default Slice-AMBR can be used for IoT S-NSSAI.

Serving network Slice-AMBR can be managed by PCF. PCF is S-NSSAI, mapping of S-NSSAIs (mapped information of subscribed S-NSSAI of the terminal and S-NSSAI of the serving network), subscribed Slice-AMBR, session-AMBR, mobile operator policy, local policy , A serving network Slice-AMBR may be determined based on a roaming agreement, or the like. For example, the PCF may be mapped to a subscribed S-NSSAI, which is a subscription network slice of the terminal, to determine a Slice-AMBR of S-NSSAI used in the serving network, that is, a serving network Slice-AMBR. This serving network Slice-AMBR may be used to support a roaming subscriber. The PCF may provide a serving network Slice-AMBR to 5G core network NF, for example, AMF and SMF.

Authorized Slice-AMBR can be managed by PCF. PCF includes S-NSSAI, mapping of S-NSSAIs (mapped information of subscribed S-NSSAI of the terminal and S-NSSAI of the serving network), subscribed Slice-AMBR, serving network Slice-AMBR, session-AMBR, mobile operator policy, The authorized Slice-AMBR may be determined based on a local policy, a roaming agreement, and the like. PCF can provide authorized Slice-AMBR to 5G core network NF, for example, AMF, SMF, etc.

5G core network NF, for example, AMF, SMF, etc., use subscribed Slice-AMBR obtained from UDM or subscribed Slice-AMBR obtained from UDM in order to manage the data rate of the network slice used by the terminal. local policy), or the serving network Slice-AMBR or/and authorized Slice-AMBR obtained from the PCF may be determined to be used.

Slice-AMBR may indicate the limit of the total bit rate expected to be provided on non-GBR QoS Flows for all of the one or more PDU sessions associated with the corresponding S-NSSAI. In addition, Slice-AMBR may represent a value measured in an AMBR averaging window. For example, if the terminal establishes three PDU sessions associated with the eMBB S-NSSAI, and the user plane of the three PDU sessions is in an active state (PDU Sessions with active user plane to RAN), the eMBB S-NSSAI Slice-AMBR can be calculated as the sum of AMBRs used by these three PDU sessions. In this case, the Slice-AMBR may be set to a value less than or equal to the subscribed Slice-AMBR or/and authorized Slice-AMBR or/and the serving network Slice-AMBR determined to be used by the 5G NF. For example, the eMBB Slice-AMBR determined to be used by 5G NF is 1 Giga bit per second (Gbps), and the AMBR intended for use by 3 PDU sessions is 200 Mega bit per second (Mbps), 100 Mbps, and 150 Mbps, respectively. In this case, the final Slice-AMBR for eMBB S-NSSAI may be set to 450 Mbps, which is the sum of AMBRs of each PDU session. According to another embodiment of the present disclosure, when the eMBB Slice-AMBR determined to be used by 5G NF is 1 Gbps, and the AMBR to be used by three PDU sessions is 500 Mbps, 300 Mbps, and 400 Mbps, respectively, the final eMBB S-NSSAI Slice-AMBR may be set to 1 Gbps. Accordingly, the 5G system can adjust the AMBR value that can be used by each PDU session.

The UE may use one or more S-NSSAIs, and the sum of Slice-AMBR for each S-NSSAI may be set to a value less than or equal to UE-AMBR. For example, UE-AMBR of the terminal is 4 Gbps, Slice-AMBR for eMBB S-NSSAI used by the terminal is 1 Gbps, Slice-AMBR for URLCC S-NSSAI is 1 Gbps, Slice-AMBR for CIoT S-NSSAI is In the case of 500 Mbps, the final UE-AMBR may be set to 2.5 Gbps, which is the sum of each Slice-AMBR. In general, CIoT may mean IoT using a cellular network as a communication method. For example, it may refer to a technology that provides IoT services in a mobile communication system (cellular network).

As another example, the UE-AMBR of the terminal is 4 Gbps, the Slice-AMBR for the eMBB S-NSSAI used by the terminal is 3 Gbps, the Slice-AMBR for URLCC S-NSSAI is 1 Gbps, and the Slice-AMBR for CIoT S-NSSAI is 500 Mbps. In this case, the final UE-AMBR may be set to 4 Gbps each. Accordingly, the 5G system can adjust the Slice-AMBR value associated with each S-NSSAI.

Based on the above description, the NF of the core network and the operation of the terminal will be described in more detail with reference to the accompanying drawings.

1 illustrates a registration procedure according to an embodiment of the present disclosure.

Prior to the description with reference to FIG. 1, a terminal (UE) 100 and network entities will be described. The terminal 100 is located within a specific base station (RAN) 101 and may communicate with the base station 101 by establishing a radio channel. As described above, the base station 101 may be a base station of a 5G network, an LTE or LTE-A base station, or may be a network entity that performs a role of a base station in other wireless communication networks. Hereinafter, for convenience of explanation, the base station 101 is assumed to be a 5G base station and the mobile communication system is a 5G wireless communication network. In addition, it is assumed that the 5G core network excluding the base station 101 includes the AMF 102, the PCF 103, and the UDM 104. A portion indicated by a dotted line in FIG. 1 described below may be a procedure that can be omitted when only signal flow is considered.

Meanwhile, the 5G system determines Slice-AMBR of S-NSSAI that the terminal 100 can use during the registration procedure of the terminal 100, and Slice-AMBR to the terminal 100, the base station 101 and the related 5G NF. Can provide.

Referring to FIG. 1, in step 110 in order to perform the registration procedure, the terminal 100 may transmit a registration request message. The Registration Request message may include a UE ID, for example, a SUPI (Subscription Permanent Identifier) 5G-GUTI (5G Globally Unique Temporary Identifier), and a Requested NSSAI intended to be used by the UE. For description of the present disclosure, it is assumed that eMBB S-NSSAI and URLLC S-NSSAI are included as Requested NSSAI.

In step 112, the base station 101 may select the AMF 102 to transmit the Registration Request message based on at least one of the received terminal ID, Requested NSSAI, and local policy. The base station 101 may deliver a Registration Request message to the selected AMF 102.

In step 114, the AMF 102 may transmit a Nudm_SDM_Get Request message for requesting subscription information of the terminal 100 to the UDM 104. The Nudm_SDM_Get Request message may include a terminal ID, for example, SUPI.

In step 116, the UDM 116 may return the terminal subscription information referred to as the terminal ID to the AMF 102. The terminal subscription information may include subscribed S-NSSAIs subscribed to by the terminal 100 and subscribed Slice-AMBR for each subscribed S-NSSAI. For example, if the terminal subscription information includes eMBB S-NSSAI, URLLC S-NSSAI, IoT S-NSSAI as a plurality of subscribed S-NSSAIs, subscribed Slice-AMBR of the terminal subscription information is subscribed for eMBB S-NSSAI Slice-AMBR, subscribed Slice-AMBR for URLLC S-NSSAI, subscribed Slice-AMBR for IoT S-NSSAI may be included. For the description of the present disclosure, it is assumed that eMBB S-NSSAI, URLLC S-NSSAI and IoT S-NSSAI are included as subscribed S-NSSAIs.

The AMF 102 that received the terminal subscription information from the UDM 104 in step 116 is at least one of the Requested NSSAI received from the terminal 100 before step 118, the subscribed S-NSSAI received from the UDM 104, and local policy. Based on the above, Allowed NSSAI can be determined. According to another embodiment of the present disclosure, in the Allowed NSSAI, in addition to the method of FIG. 1, the AMF 102 may obtain the Allowed NSSAI from NSSF (not shown in FIG. 1 ). For example, AMF 102 or/and NSSF confirms that eMBB S-NSSAI and URLLC S-NSSAI included in Requested NSSAI are included in subscribed S-NSSAIs, and eMBB S-NSAAI and URLLC S-NSSAI as Allowed NSSAI You can decide to provide. AMF 102 may store the Allowed NSSAI and subscribed Slice-AMBR in the UE context of the terminal 100.

In step 118, the AMF 102 may establish an Access and Mobility (AM) policy association with the PCF 103 or/and a UE policy association. In the Policy Association Request message sent by the AMF 102 to the PCF 103, subscribed S-NSSAI, Allowed NSSAI, mapping of S-NSSAIs, subscribed Slice-AMBR, SUPI, HPLMN (Home Public Land Mobile Network) ) At least one or more of the IDs may be included. In this case, the subscribed Slice-AMBR may include all subscribed Slice-AMBRs received by the AMF 102 from the UDM 104). According to an embodiment of the present disclosure, all subscribed Slice-AMBRs received from UDM 104 by AMF 102 are subscribed Slice-AMBR for eMBB S-NSSAI, subscribed Slice-AMBR for URLLC S-NSSAI, IoT It may include subscribed Slice-AMBR for S-NSSAI. According to another embodiment of the present disclosure, the subscribed Slice-AMBR may include only subscribed Slice-AMBR for the S-NSSAI included in the AMF 102 or/and the Allowed NSSAI determined by NSSF. To illustrate this in detail, the subscribed Slice-AMBR is a subscribed Slice-AMBR for S-NSSAI included in the Allowed NSSAI determined by AMF 102 or/and NSSF is subscribed Slice-AMBR for eMBB S-NSSAI, URLLC It may include only subscribed Slice-AMB for S-NSSAI.

In step 120, the PCF 103 may determine the serving network Slice-AMBR of each subscribed Slice-AMBR received. For example, the PCF 103 may determine the HPLMN of the terminal based on the received SUPI or HPLMN ID, and the PCF 103 is mapped to subscribed S-NSSAI, mapping of S-NSSAIs (subscribed S-NSSAIs) to serve The serving network Slice-AMBR for the S-NSSAI used in the serving network may be determined based on the S-NSSAI used in the network) and the roaming agreement with the HPLMN. The Subscribed Slice-AMBR and the serving network Slice-AMBR determined by the PCF 103 may be the same or different. The PCF 103 may establish a policy association by transmitting a Policy Association Response message to the AMF 102. A serving network Slice-AMBR may be included in the Policy Association Response message.

AMF 102 receiving the serving network Slice-AMBR from the PCF 103 is a Slice-AMBR to be used for each S-NSSAI included in the Allowed NSSAI of the terminal 100, and subscribed Slice-AMBR or/and subscribed Slice Based on -AMBR, it may be determined to use one of Slice-AMBR modified by AMF 102 or/and serving network Slice-AMBR received from PCF 103. The AMF 102 may add Slice-AMBR to the UE context of the UE 100.

In step 122, the AMF 102 may transmit an N2 message to the base station 101. The N2 message may include an Allowed NSSAI, a Slice-AMBR, UE-AMBR, and a Registration Accept message transmitted by the AMF 102 to the UE 100 for each S-NSSAI included in the Allowed NSSAI. The Registration Accept message may include Slice-AMBR for each S-NSSAI included in Allowed NSSAI and Allowed NSSAI.

The base station 101 receiving the N2 message may store the Allowed NSSAI for the UE 100, Slice-AMBR, and UE-AMBR for each S-NSSAI included in the Allowed NSSAI. The base station 101 may use the stored Slice-AMBR and UE-AMBR in order to control the uplink and downlink data traffic rates of the terminal afterwards. According to various embodiments of the present disclosure, when an operation is illustrated with only a signal flow, this operation may be omitted.

In step 124, the base station 101 may transmit a registration acceptance message to the terminal 100. Even at this time, the Registration Accept message may include Slice-AMBR for each S-NSSAI included in the Allowed NSSAI and Allowed NSSAI.

Upon receiving the Registration Accept message, the terminal 100 may store the Allowed NSSAI and Slice-AMBR for each S-NSSAI included in the Allowed NSSAI. The terminal 100 may use the stored Slice-AMBR in order to control the uplink data traffic rate in a later procedure. According to various embodiments of the present disclosure, when an operation is illustrated with only a signal flow, this operation may be omitted.

According to various embodiments of the present disclosure, the terminal 100, the base station 101, and the AMF 102 may acquire and store Slice-AMBR information through the procedure illustrated in FIG. 1 described above. In addition, the base station 101 and the AMF 102 may provide a service to the terminal 100 by using Slice-AMBR information obtained through the procedure of FIG. 1 described above.

2 illustrates a PDU Session Establishment procedure according to an embodiment of the present disclosure.

Prior to the description with reference to FIG. 2, the terminal (UE) 100 and network entities will be described. The terminal 100 is located within a specific base station (RAN) 101 and may communicate with the base station 101 by establishing a radio channel. As described above, the base station 101 may be a base station of a 5G network, an LTE or LTE-A base station, or may be a network entity that performs a role of a base station in other wireless communication networks. Hereinafter, for convenience of explanation, the base station 101 is assumed to be a 5G base station and the mobile communication system is a 5G wireless communication network. In addition, the 5G core network excluding the base station 101 will be described on the assumption that AMF 102, SMF1 200, PCF 103, UPF 202, UDM 104 and DN 203 are included. Here, the PCF 103 of FIG. 1 and the PCF 103 of FIG. 2 may be the same component. In addition, a portion indicated by a dotted line in FIG. 2 may be a procedure that can be omitted when only signal flow is considered.

Meanwhile, the 5G system determines the Slice-AMBR of the S-NSSAI associated with the PDU session during the PDU session establishment procedure, and the terminal 100, the base station 101 and the related 5G NF, e.g., SMF1 200, UPF Slice-AMBR can be provided to (202) and the like.

The terminal 100 according to an embodiment of the present disclosure may start a PDU session establishment procedure in order to be connected to the DN 203 to transmit and receive data. Referring to FIG. 2, in step 210 to establish a PDU session, the terminal 100 may transmit a PDU session establishment request message through the base station 101. The PDU Session Establishment Request message may include at least one of a PDU Session ID, an S-NSSAI intended to be used by the terminal 100, and a DNN.

In step 212, the AMF 102 may select an SMF capable of managing the PDU session requested by the terminal 100. For example, the AMF 102 may select an SMF that supports the S-NSSAI and/or DNN requested by the terminal 100.

In step 214, the AMF 102 may transmit a PDU session creation request message to the selected SMF1 200. The PDU Session Create Request message may include at least one or more of PDU Session ID, S-NSSAI, DNN, and serving network Slice-AMBR.

The SMF1 200 may create a session management (SM) context. The SM Context is a set of information for managing the PDU session requested in step 214. SM Context may be referred to as SM Context ID. The SM Context may allocate one SM Context to one terminal, or set a plurality of SM Contexts. For example, when a plurality of PDU sessions are allocated to one terminal, an SM Context may be allocated for each PDU session. In this case, a plurality of SM Context IDs may be allocated to one terminal.

In step 216, the SMF1 200 may request the UDM 104 for subscription information of the terminal 100, and obtain the terminal subscription information from the UDM 104. The terminal subscription information may include at least one or more of subscribed S-NSSAI, subscribed Slice-AMBR for subscribed S-NSSAI, subscribed S-NSSAI and subscribed session-AMBR for DNN.

The SMF1 200 may authenticate the terminal request received in step 214 based on the terminal subscription information. For example, the SMF1 200 may check whether the S-NSSAI and/or DNN requested by the terminal included in the PDU Session Create Request message are included in the terminal subscription information.

In step 218, the SMF1 200 may return a PDU session creation response message to the AMF 102. When the authentication performed in step 216 is successful, the SM Context ID may be included in the PDU Session Create Response message.

The AMF 102 may store the received SM Context ID. The AMF 102 may use the SM Context ID to indicate the SM Context for the PDU session referred to as the PDU Session ID.

In step 220, the SMF1 (200) may establish an SM policy association with the PCF (103). The PCF 103 establishing the SM policy association with the SMF1 200 may be the same as or different from the PCF 103 establishing the policy association by the AMF 102 in the registration procedure. In the Policy Association Request message transmitted from the SMF1 200 to the PCF 103, S-NSSAI for establishing a PDU session, subscribed Slice-AMBR, serving network Slice-AMBR, subscribed session-AMBR, SUPI, At least one of HPLMN IDs may be included. In this case, the subscribed Slice-AMBR may be a subscribed Slice-AMBR in a PDU session set corresponding to a specific S-NSSAI. To explain this by way of example, subscribed Slice-AMBR may be a value corresponding to S-NSSAI. That is, when the terminal has two PDU sessions, if the two PDU sessions use the same S-NSSAI, the subscribed Slice-AMBR for the two PDU sessions may also be the same. In addition, the subscribed Slice-AMBR is a value stored in the UDM as UE subscription data, so even if the UE does not establish a PDU session with the corresponding S-NSSAI, it may always be stored in the UDM. In addition, the serving network Slice-AMBR may be a serving network Slice-AMBR used in a serving network for a PDU session.

In step 222, the PCF 103 may determine the received subscribed Slice-AMBR or/and the authorized Slice-AMBR of the serving network Slice-AMBR based on at least one of terminal subscription information and a local policy. In addition, when the PCF 103 determines the authorized Slice-AMBR, a roaming agreement with the HPLMN of the terminal 100 may be considered. Subscribed Slice-AMBR to serving network Slice-AMBR and authorized Slice-AMBR determined by the PCF 103 may be the same or different. In addition, the PCF 103 may determine the authorized session-AMBR. Authorized session-AMBR may be less than or equal to authorized Slice-AMBR. The PCF 103 may establish a policy association by transmitting a Policy Association Response message to the SMF1 200. The Policy Association Response message may include at least one of authorized Slice-AMBR and authorized session-AMBR.

SMF1 (200) is a Slice-AMBR to be used for the S-NSSAI associated with the PDU session, and the Slice-modified by the AMF 102 or the SMF1 200 based on the subscribed Slice-AMBR or/and the subscribed Slice-AMBR- It may be determined to use one of AMBR or/and serving network Slice-AMBR or/and authorized Slice-AMBR. The SMF1 200 may add Slice-AMBR to the SM context of the terminal 100. In addition, the SMF1 200 may add a session-AMBR to the SM context of the terminal 100.

In step 224, the SMF1 200 may establish an N4 session with the UPF 202 selected for establishing a PDU session. The N4 Session Establishment Request message transmitted from the SMF1 200 to the UPF 202 may include at least one of Slice-AMBR and session-AMBR for a PDU session. The UPF 202 may store the received Slice-AMBR and session-AMBR, and then use it to control downlink data and/or uplink data traffic.

In step 226, the UPF 202 may return an N4 Session Establishment Response message to the SMF1 200.

In step 228, the SMF1 200 may transmit a Namf_Communication_N1N2MessageTransfer message to the AMF 102. In the Namf_Communication_N1N2MessageTransfer message, at least one of information transmitted from SMF1 (200) to AMF (102), N2 message transmitted from SMF1 (200) to base station 101, and N1 message transmitted from SMF1 (200) to terminal 100 The above may be included.

The information transmitted by the SMF1 200 to the AMF 102 may include at least one of a PDU Session ID, an SM Context ID, and a Slice-AMBR.

The N2 message transmitted from the SMF1 200 to the base station 101 through the AMF 102 may include at least one of a PDU Session ID, Session-AMBR, S-NSSAI, and Slice-AMBR.

In the N1 message transmitted from the SMF1 200 to the terminal 100 through the AMF 102 and the base station 101, PDU session establishment acceptance including at least one or more of S-NSSAI, Session-AMBR, and Slice-AMBR (Session Establishment Accept) message may be included.

In step 230, the AMF 102 may return a Namf_Communication_N1N2MessageTransfer response message to the SMF1 200 based on the message received in step 228.

In step 232, the AMF 102 may transmit an N2 PDU Session Request message to the base station 101. The N2 PDU Session Request message may include the N2 message received by the AMF 102 from the SMF1 200.

The base station 101 stores the S-NSSAI and Slice-AMBR together with the PDU Session ID received at the 232 terminal, and then uses it to control downlink data and/or uplink data traffic of the PDU session associated with the S-NSSAI. I can. At this time, when Slice-AMBR information for the S-NSSAI exists in the base station 101 (for example, as shown in step 122 of FIG. 1, Slice-AMBR for S-NSSAI is obtained during the terminal registration procedure) In one case, when there is base station configuration information, etc.), the base station 101 may use Slice-AMBR information previously stored in the base station 101 instead of the Slice-AMBR received in step 232. According to another embodiment of the present disclosure, the base station 101 may use the Slice-AMBR information received in step 232 instead of the previously stored Slice-AMBR information.

In step 234, the base station 101 may perform an access network-specific resource setup procedure with the terminal 100. During the AN-specific resource setup procedure, the base station 101 may transmit a PDU Session Establishment Accept message received from the AMF 102 to the terminal 100. The terminal 100 may store the received Slice-AMBR and then use it to control uplink data traffic of the PDU session associated with the S-NSSAI. At this time, when Slice-AMBR information for the S-NSSAI exists in the terminal 100 (for example, as shown in step 124 of FIG. 1, Slice-AMBR for S-NSSAI is obtained during the terminal registration procedure) In one case, when terminal configuration information or terminal policy information exists), the terminal 100 may use Slice-AMBR information previously stored in the terminal 100 instead of the Slice-AMBR received in step 234. According to another embodiment of the present disclosure, the terminal 100 may use the Slice-AMBR information received in step 234 instead of the previously stored Slice-AMBR information.

The SMF1 200 having successfully performed the PDU session establishment procedure may register the SMF1 200 itself with the UDM 104 as a serving SMF of the PDU session in step 236. The UDM 104 may store the SMF instance ID of the SMF1 200.

The terminal 100 may transmit uplink data to the DN 203 via the base station 101 and the UPF 202. In addition, the DN 203 may transmit downlink data to the terminal 100 via the UPF 202 and the base station 101.

[Example 2]

After establishing a PDU session for S-NSSAI through the procedure shown in FIG. 2, a terminal according to various embodiments of the present disclosure may transmit and receive DN and uplink and downlink data traffic. In addition, the terminal according to various embodiments of the present disclosure may establish another PDU session for the same S-NSSAI. For example, a first PDU session may be established to communicate with DN1 (203), and a second PDU session may be established to communicate with DN2 (300). At this time, since the first PDU session and the second PDU session are associated with the same S-NSSAI, in the 5G system, the sum of the uplink and downlink data traffic of the first PDU session and the second PDU session is S-NSSAI. It should be able to control less than or equal to the total sum of Slice-AMBR linked to. In the above example, two PDU sessions have been described as an example, but according to various embodiments of the present disclosure described above, even when three or more PDU sessions are configured, the same may be set.

In the second embodiment, in selecting the SMF and UPF for the second PDU session, the same SMF and UPF as the first PDU session are selected, and in the SMF and/or UPF, the first PDU session and the second PDU session S- A method of managing Slice-AMBR for NSSAI and controlling the sum of uplink and downlink data traffic is described.

3A and 3B illustrate a PDU Session Establishment procedure according to an embodiment of the present disclosure.

3A and 3B may be a continuous signal flow diagram for describing FIGS. 3A and 3B. For example, after the operation of the flowchart of FIG. 3A, the operation of FIG. 3B may be performed. However, in a specific case, a case where the order must be changed or omitted will be described separately. In addition, a terminal (UE) 100 and network entities will be described in FIGS. 3A and 3B. The terminal 100 is located within a specific base station (RAN) 101 and may communicate with the base station 101 by establishing a radio channel. As described above, the base station 101 may be a base station of a 5G network, an LTE or LTE-A base station, or may be a network entity that performs a role of a base station in other wireless communication networks. Hereinafter, for convenience of explanation, the base station 101 is assumed to be a 5G base station and the mobile communication system is a 5G wireless communication network. In addition, the 5G core network excluding the base station 101 includes AMF (102), SMF1 (200), PCF (103), UPF (202), UDM (104), DN1 (203) and DN2 (300). Explain assuming. Here, DN1 203 and DN2 300 may be logically or/and physically different DNs. Also in FIGS. 3 and 3B, portions indicated by dotted lines may be a procedure that can be omitted when only signal flow is considered.

3A and 3B, the terminal 100 establishes a first PDU session for S-NSSAI as shown in FIG. 2, and transmits the DN1 203 and uplink data and/or downlink data traffic. You can give and receive. The terminal 100, the base station 101, and the UPF 202 may store Slice-AMBR for S-NSSAI and control the data rate of uplink data and/or downlink data traffic.

Terminal 100 according to an embodiment of the present disclosure, based on at least one of the terminal policy (UE Policy) of the terminal and local configuration information (local configuration), for the S-NSSAI associated with the first PDU session It may be determined to establish another PDU session, that is, a second PDU session.

In step 310, the terminal 100 may transmit a PDU session establishment request message to establish a second PDU session. The PDU Session Establishment Request message may include at least one of a PDU Session ID, an S-NSSAI intended to be used by the terminal 100, and a DNN. In this case, the S-NSSAI included in the PDU Session Establishment Request may be the same as the S-NSSAI for the first PDU session. In addition, the DNN included in the PDU Session Establishment Request may be the same as or different from the DNN for the first PDU session.

In step 312, the AMF 102 may select an SMF capable of managing the PDU session requested by the terminal 100. The AMF 102 according to various embodiments of the present disclosure confirms that there is a PDU session, that is, a first PDU session, concluded with the S-NSSAI requested by the terminal 100 based on the UE context stored in the AMF 102. In addition, the AMF 102 may select the serving SMF1 200 of the first PDU session as the SMF for the second PDU session.

In step 314, the AMF 102 may transmit a PDU session creation request message to the selected SMF1 200. The PDU Session Create Request message may include at least one of a PDU Session ID, S-NSSAI, and DNN. In addition, the AMF 102 may include the SM Context ID or PDU Session ID linked to the first PDU session in the PDU Session Create Request message. By including the SM Context ID or PDU Session ID linked to the first PDU session in the PDU Session Create Request message, the AMF 102 tells the SMF1 200 that the second PDU session request is related to the first PDU session (e.g. For example, a PDU session using the same S-NSSAI) can be announced.

The SMF1 200 may create an SM Context for a second PDU session. The SM Context is a set of information for managing the PDU session requested in step 314. SM Context may be referred to as SM Context ID.

In step 316, the SMF1 200 may request the UDM 104 for subscription information of the terminal 100, and obtain the terminal subscription information from the UDM 104. The terminal subscription information may include at least one or more of subscribed S-NSSAI, subscribed Slice-AMBR for subscribed S-NSSAI, subscribed S-NSSAI and subscribed session-AMBR for DNN. According to another embodiment of the present disclosure, the SMF1 200 may omit step 316 and use the terminal subscription information received in step 216 of FIG. 2.

The SMF1 200 may authenticate the terminal request received in step 314 based on the terminal subscription information. For example, the SMF1 200 may check whether the S-NSSAI and/or DNN requested by the terminal included in the PDU Session Create Request message are included in the terminal subscription information.

In step 318, SMF1 (200) may return a PDU session creation response (Session Create Response) message to the AMF (102). The PDU Session Create Response message may include an SM Context ID for the second PDU session.

The AMF 102 may store the received SM Context ID. The AMF 102 may use the second SM Context ID to indicate the SM Context for the second PDU session referred to as the second PDU Session ID.

In step 320, the SMF1 200 may establish an SM policy association for the PCF 103 and the second PDU session. The PCF 103 in which the SMF1 200 establishes SM policy association may be the same as or different from the PCF 103 in which the SMF1 200 establishes policy association in the first PDU session establishment procedure. In the Policy Association Request message transmitted from the SMF1 200 to the PCF 103, S-NSSAI for establishing a second PDU session, subscribed Slice-AMBR, serving network Slice-AMBR, subscribed session-AMBR, At least one of SUPI and HPLMN ID may be included. In this case, the subscribed Slice-AMBR may be a subscribed Slice-AMBR in the second PDU session set in response to the S-NSSAI. To explain this by way of example, subscribed Slice-AMBR may be a value corresponding to S-NSSAI. That is, when the terminal establishes two PDU sessions, if the two PDU sessions use the same S-NSSAI, the subscribed Slice-AMBR for the two PDU sessions may also be the same. In addition, the subscribed Slice-AMBR is a value stored in the UDM as UE subscription data, so even if the UE does not establish a PDU session with the corresponding S-NSSAI, it may always be stored in the UDM. In addition, the serving network Slice-AMBR may be a serving network Slice-AMBR used in a serving network for a second PDU session.

In step 322, the PCF 103 may determine the authorized Slice-AMBR of the received subscribed Slice-AMBR to the serving network Slice-AMBR based on at least one of terminal subscription information and local policy. In addition, when the PCF 103 determines the authorized Slice-AMBR, a roaming agreement with the HPLMN of the terminal may be considered. Subscribed Slice-AMBR to serving network Slice-AMBR and authorized Slice-AMBR determined by the PCF 103 may be the same or different. In addition, the PCF 103 may determine the authorized session-AMBR. Authorized session-AMBR may be less than or equal to authorized Slice-AMBR. The PCF 103 may establish a policy association by transmitting a Policy Association Response message to the SMF1 200. The Policy Association Response message may include at least one of authorized Slice-AMBR and authorized session-AMBR.

According to another embodiment of the present disclosure, the SMF1 200 may use the authorized Slice-AMBR and authorized Session-AMBR information received in step 222 of FIG. 2.

According to another embodiment of the present disclosure, the SMF1 200 may use both the authorized Slice-AMBR received in step 222 of FIG. 2 and the authorized session-AMBR information received in step 322.

The SMF1 200 may determine Slice-AMBR to be used for the first PDU session and the second PDU session. For example, the SMF1 200 may use the Slice-AMBR determined during the first PDU session establishment procedure as shown in FIG. 2 for the second PDU session. According to another embodiment of the present disclosure, the SMF1 200 may newly determine the Slice-AMBR during the second PDU session establishment procedure, and if the newly determined Slice-AMBR is different from the Slice-AMBR determined during the first PDU session establishment procedure In this case, the SMF1 200 may add Slice-AMBR to the SM context of the first PDU session of the terminal 100, and may perform step 350.

Slice-AMBR to be used for the first PDU session and the second PDU session may be set as the sum of the AMBR of the first PDU session and the AMBR of the second PDU session. At this time, when the sum of the AMBR of the first PDU session and the AMBR of the second PDU session is greater than the values of subscribed Slice-AMBR to serving network Slice-AMBR to authorized Slice-AMBR, the SMF1 200 corresponds to the first PDU session and Slice-AMBR to be used for the second PDU session, modified by AMF 102 or SMF1 200 based on subscribed Slice-AMBR to subscribed Slice-AMBR to Slice-AMBR to serving network Slice-AMBR to authorized Slice-AMBR You can decide to use one of them. The SMF1 200 may add Slice-AMBR to the SM context of the second PDU session of the terminal 100. In addition, the SMF1 200 may add a session-AMBR for the second PDU session to the SM context of the second PDU session of the terminal 100.

In step 324, the SMF1 200 may establish an N4 session with the UPF 202 selected for establishing a second PDU session. For example, the SMF1 200 may select the UPF 202 of the first PDU session as the UPF for the second PDU session. The N4 Session Establishment Request message transmitted from the SMF1 200 to the UPF 202 may include at least one of Slice-AMBR and session-AMBR for the second PDU session. The UPF 202 may store the received Slice-AMBR and session-AMBR, and then use it to control downlink data and/or uplink data traffic. For example, the UPF 202 is a downlink data traffic transmitted through a core network (CN) tunnel used for a first PDU session and a downlink data traffic transmitted through a CN tunnel used for a second PDU session. The sum of the link data traffic can be controlled to be less than or equal to the received Slice-AMBR. When downlink traffic exceeding Slice-AMBR occurs, the UPF 202 may discard some data of the downlink data traffic of the first PDU session and/or the second PDU session.

In step 326, the UPF (202) may return an N4 session establishment response (Session Establishment Response) message to the SMF1 (200).

In step 328, the SMF1 200 may transmit a Namf_Communication_N1N2MessageTransfer message to the AMF 102. Namf_Communication_N1N2MessageTransfer message is at least one of information transmitted from SMF1 (200) to AMF (102), N2 message transmitted from SMF1 (200) to base station 101, and N1 message transmitted from SMF1 (200) to terminal 100 It may include more than one.

The information transmitted from the SMF1 200 to the AMF 102 may include at least one of a PDU Session ID, an SM Context ID, and a Slice-AMBR.

The N2 message transmitted from the SMF1 200 to the base station 101 may include at least one of a PDU Session ID, Session-AMBR, S-NSSAI, and Slice-AMBR.

The N1 message transmitted from the SMF1 200 to the terminal 100 may include a PDU session establishment acceptance message including at least one of S-NSSAI, Session-AMBR, and Slice-AMBR.

In step 330, the AMF 102 may return a Namf_Communication_N1N2MessageTransfer Response message to the SMF1 200.

In step 332, the AMF 102 may transmit an N2 PDU session request message to the base station 101. The N2 PDU Session Request message may include the N2 message received by the AMF 102 from the SMF1 200.

The base station 101 can store the S-NSSAI and Slice-AMBR together with the received PDU Session ID, and then use it to control downlink data and/or uplink data traffic of the second PDU session. For example, the base station 101 has the sum of the uplink data traffic or downlink data traffic of the first PDU session and the uplink data traffic or the downlink data traffic of the second PDU session is less than the received Slice-AMBR, or You can control it the same way. When uplink traffic or downlink traffic exceeding Slice-AMBR occurs, the base station 101 may discard some of the data traffic of the first PDU session and/or the second PDU session.

In step 334, the base station 101 may perform an AN-specific resource setup procedure with the terminal 100. During the AN-specific resource setup procedure, the base station 101 may transmit a PDU Session Establishment Accept message received from the AMF 102 to the terminal 100. The terminal 100 may store the received Slice-AMBR and then use it to control uplink data traffic of the PDU session associated with the S-NSSAI. For example, the terminal 100 may control the sum of the uplink data traffic of the first PDU session and the uplink data traffic of the second PDU session to be less than or equal to the received Slice-AMBR. When uplink data traffic exceeding Slice-AMBR occurs, the terminal 100 first transmits a PDU session and/or data traffic with a high priority, and transmits a PDU session and/or data traffic with a low priority later. Or discard some data.

The SMF1 200 having successfully performed the second PDU session establishment procedure may register the SMF1 200 itself with the UDM 104 as a serving SMF of the second PDU session in step 336. The UDM 104 may store the SMF instance ID of the SMF1 200.

The terminal 100 may transmit uplink data to the DN 203 via the base station 101 and the UPF 202. In addition, the DN 203 may transmit downlink data to the terminal 100 via the UPF 202 and the base station 101.

According to an embodiment of the present disclosure, the Slice-AMBR determined during the second PDU session establishment procedure may be different from the Slice-AMBR determined during the first PDU session establishment procedure. The terminal 100, the base station 101, and the UPF 202 can use the Slice-AMBR received during the second PDU session establishment procedure to control uplink and/or downlink data traffic for the first PDU session. have. According to another embodiment of the present disclosure, the SMF1 200 performs steps 352 and 354 to provide the terminal 100, the base station 101 and the UPF 202 with a modified Slice-AMBR to be used for the first PDU session. Can be transmitted. The terminal 100 may use the Slice-AMBR received in step 360 to control the uplink data traffic of the first PDU session. The base station 101 may use the Slice-AMBR received in step 358 to control uplink and/or downlink data traffic of the first PDU session. The UPF 202 may use the Slice-AMBR received in step 352 to control downlink data traffic of the first PDU session.

[Example 3]

After establishing a PDU session for S-NSSAI through the procedure shown in FIG. 2, a terminal according to various embodiments of the present disclosure may transmit and receive DN and uplink and downlink data traffic. In addition, the terminal according to various embodiments of the present disclosure may establish another PDU session for the same S-NSSAI. For example, a first PDU session may be established to communicate with DN1 (203), and a second PDU session may be established to communicate with DN2 (300). At this time, since the first PDU session and the second PDU session are associated with the same S-NSSAI, in the 5G system, the sum of the uplink and downlink data traffic of the first PDU session and the second PDU session is S-NSSAI. It should be able to control less than or equal to the total sum of Slice-AMBR linked to.

In Example 3, in selecting the SMF for the second PDU session, the same SMF as the first PDU session is selected, and this SMF manages the Slice-AMBR for the S-NSSAI of the first PDU session and the second PDU session. Then, a method of controlling the sum of the uplink and downlink data traffic will be described. According to the method described in Embodiment 3, the UPF selected for the first PDU session and the UPF selected for the second PDU session may be different.

4A and 4B illustrate a PDU Session Establishment procedure according to an embodiment of the present disclosure.

Prior to describing FIGS. 4A and 4B, FIGS. 4A and 4B may be a continuous signal flow diagram. For example, after the operation of the flowchart of FIG. 4A, the operation of FIG. 4B may be performed. However, in a specific case, a case where the order must be changed or omitted will be described separately. In addition, a terminal (UE) 100 and network entities will be described in FIGS. 4A and 4B. The terminal 100 is located within a specific base station (RAN) 101 and may communicate with the base station 101 by establishing a radio channel. As described above, the base station 101 may be a base station of a 5G network, an LTE or LTE-A base station, or may be a network entity that performs a role of a base station in other wireless communication networks. Hereinafter, for convenience of explanation, the base station 101 is assumed to be a 5G base station and the mobile communication system is a 5G wireless communication network. In addition, 5G core networks excluding base station 101 include AMF (102), SMF1 (200), PCF (103), UPF1 (202), UPF2 (400), UDM (104), DN1 (203) and DN2 (300). It will be described on the assumption that it includes. Here, DN1 203 and DN2 300 may be logically or/and physically different DNs. In addition, the UPF1 202 and the UPF2 400 may be logically or/and physically different UPFs. Also in FIGS. 4A and 4B, a portion indicated by a dotted line may be a procedure that can be omitted when only the signal flow is considered.

4A and 4B, the terminal 100 establishes a first PDU session for S-NSSAI as shown in FIGS. 2 to 3A and 3B, and a second PDU session for the same S-NSSAI. The establishment process can be started. In more detail, steps 210 to 236 of Fig. 2 are performed (the first block in Fig. 4A), and then steps 310 to 322 of Figs. 3A and 3B are performed (the second block of Fig. 4A). After that, the SMF1 200 may determine a Slice-AMBR to be used for the first PDU session and the second PDU session.

The SMF1 200 according to an embodiment of the present disclosure may determine a session-AMBR for a first PDU session and a session-AMBR for a second PDU session in consideration of this Slice-AMBR.

In step 424, the SMF1 200 may establish an N4 session with the UPF 202 selected for establishing a second PDU session. For example, the SMF1 200 according to an embodiment of the present disclosure includes a PDU session established by the S-NSSAI requested by the terminal 100 based on the SM context stored by the SMF1 200, that is, a first PDU session. It can be confirmed that there is. When the DNN of the first PDU session is different from the DNN requested for establishing the second PDU session, the SMF1 200 may select a different UPF. Alternatively, when the DNN of the first PDU session is the same as the DNN requested for establishing the second PDU session, the SMF1 200 may select the same UPF as described in the second embodiment. 4A and 4B illustrate a case of selecting a different UPF.

The N4 Session Establishment Request message transmitted from the SMF1 200 to the UPF 400 may include at least one of Slice-AMBR and session-AMBR for a second PDU session. The UPF 400 may store the received Slice-AMBR and session-AMBR, and then use it to control downlink data and/or uplink data traffic.

In step 426, the UPF 202 may return an N4 Session Establishment Response message to the SMF1 200.

Upon receiving the N4 Session Establishment Response message, the SMF1 200 may perform step 336 in step 328 of FIG. 2.

The base station 101 may store the S-NSSAI and Slice-AMBR together with the received PDU Session ID, and then use it to control downlink data and/or uplink data traffic of the second PDU session. For example, the base station 101 is a Slice-AMBR received by the sum of the uplink data traffic and/or downlink data traffic of the first PDU session and the uplink data traffic and/or downlink data traffic of the second PDU session. It can be controlled to be less than or equal to. When uplink traffic or downlink traffic exceeding Slice-AMBR occurs, the base station 101 may discard some of the data traffic of the first PDU session and/or the second PDU session.

The terminal 100 may store the received Slice-AMBR and then use it to control uplink data traffic of the PDU session associated with the S-NSSAI. For example, the terminal 100 may control the sum of the uplink data traffic of the first PDU session and the uplink data traffic of the second PDU session to be less than or equal to the received Slice-AMBR. When uplink data traffic exceeding Slice-AMBR occurs, the terminal 100 first transmits a PDU session or data traffic with a high priority, and transmits a PDU session or data traffic with a low priority later, or some data Can be thrown away.

According to an embodiment of the present disclosure, each Session-AMBR may be set to a value less than or equal to Slice-AMBR. The UPF 202 controls downlink data traffic using session-AMBR used for the first PDU session, and the UPF 400 controls downlink data traffic using session-AMBR used for the second PDU session. Can be controlled.

When the sum of the session-AMBR of the first PDU session and the session-AMBR of the second PDU session is less than or equal to Slice-AMBR, the first PDU transmitted to the base station 101 through the UPF 202 and the UPF 400 The sum of the downlink data traffic of the session and the second PDU session may not exceed Slice-AMBR managed by the base station 101.

When the sum of the session-AMBR of the first PDU session and the session-AMBR of the second PDU session is greater than Slice-AMBR, the first PDU session transmitted to the base station 101 through the UPF 202 and the UPF 400 The sum of downlink data traffic of the second PDU session may exceed Slice-AMBR managed by the base station 101. In this case, the base station 101 may discard some data of the downlink data traffic of the first PDU session and/or the second PDU session.

The terminal 100 may transmit uplink data to the DN1 203 via the base station 101 and the UPF 202. Further, the DN1 203 may transmit downlink data to the terminal 100 through the UPF 202 and the base station 101.

According to various embodiments of the present disclosure, the Slice-AMBR determined during the second PDU session establishment procedure may be different from the Slice-AMBR determined during the first PDU session establishment procedure. The SMF1 200 may perform step 360 in step 350 described in FIGS. 3A and 3B. The terminal 100, the base station 101, and the UPF 202 may control uplink and/or downlink data traffic using the updated Slice-AMBR for the first PDU session.

[Example 4]

After establishing a PDU session for S-NSSAI through the procedure shown in FIG. 2, a terminal according to various embodiments of the present disclosure may transmit and receive DN and uplink and downlink data traffic. In addition, the terminal according to various embodiments of the present disclosure may establish another PDU session for the same S-NSSAI. For example, a first PDU session may be established to communicate with DN1 (203), and a second PDU session may be established to communicate with DN2 (300). At this time, since the first PDU session and the second PDU session are associated with the same S-NSSAI, in the 5G system, the sum of the uplink and downlink data traffic of the first PDU session and the second PDU session is S-NSSAI and It should be able to control less than or equal to the total sum of the connected Slice-AMBR.

Embodiment 4 describes a method of managing Slice-AMBR for S-NSSAI of a first PDU session and a second PDU session in AMF, and controlling the sum of uplink and downlink data traffic. According to the method described in Embodiment 4, the SMF and/or UPF for the first PDU session and the SMF and/or UPF for the second PDU session may be different.

5A and 5B illustrate a PDU Session Establishment procedure according to an embodiment of the present disclosure.

In order to describe FIGS. 5A and 5B, FIGS. 5A and 5B may be a continuous signal flow diagram. For example, after the operation of the flowchart of FIG. 5A, the operation of FIG. 5B may be performed. However, in a specific case, a case where the order must be changed or omitted will be described separately. In addition, a terminal (UE) 100 and network entities will be described in FIGS. 5A and 5B. The terminal 100 is located within a specific base station (RAN) 101 and may communicate with the base station 101 by establishing a radio channel. As described above, the base station 101 may be a base station of a 5G network, an LTE or LTE-A base station, or may be a network entity that performs a role of a base station in other wireless communication networks. Hereinafter, for convenience of explanation, the base station 101 is assumed to be a 5G base station and the mobile communication system is a 5G wireless communication network. In addition, 5G core networks excluding base station 101 include AMF (102), SMF1 (200), SMF2 (500), PCF (103), UPF1 (202), UPF2 (400), UDM (104), DN1 (203). And DN2 (300) will be described. Here, DN1 203 and DN2 300 may be logically or/and physically different DNs. In addition, the UPF1 202 and the UPF2 400 may be logically or/and physically different UPFs. In addition, the SMF1 200 and the SMF2 500 may be logically or/and physically different SMFs. In addition, in FIGS. 5A and 5B, a portion indicated by a dotted line may be a procedure that can be omitted when only the signal flow is considered. In addition, signal flows indicated by dotted lines in FIGS. 5A and 5B may or may not be performed selectively.

5A and 5B, the UE 100 establishes a first PDU session for S-NSSAI as shown in FIG. 2, and transmits DN1 203 and uplink data and/or downlink data traffic. You can give and receive. The terminal 100, the base station 101, and the UPF 202 may store Slice-AMBR for S-NSSAI and control the data rate of uplink data and/or downlink data traffic.

During the first PDU session establishment procedure, the Namf_Communication_N1N2MessageTransfer message transmitted by the SMF1 200 to the AMF 102 in step 328 may include Slice-AMBR information and session-AMBR information used by the first PDU session for S-NSSAI. have. The AMF 102 may store such Slice-AMBR information and session-AMBR information in a UE context.

Terminal 100 according to an embodiment of the present disclosure, based on at least one of the terminal policy (UE Policy) and local configuration information (local configuration) of the terminal, for the S-NSSAI associated with the first PDU session It may be determined to establish another PDU session, that is, a second PDU session.

In step 510, the terminal 100 may transmit a PDU session establishment request message to establish a second PDU session. The PDU Session Establishment Request message may include at least one of a PDU Session ID, an S-NSSAI intended to be used by the terminal 100, and a DNN. In this case, the S-NSSAI included in the PDU Session Establishment Request may be the same as the S-NSSAI for the first PDU session. In addition, the DNN included in the PDU Session Establishment Request may be the same as or different from the DNN for the first PDU session.

In step 512, the AMF 102 may select an SMF capable of managing a PDU session requested by the terminal 100. For example, the AMF 102 may select an SMF that supports the S-NSSAI and/or DNN requested by the terminal 100. According to an embodiment of the present disclosure, the SMF selected by the AMF 102 may be different from the serving SMF1 200 of the first PDU session.

In step 514, the AMF 102 may transmit a PDU session creation request message to the selected SMF2 500. The PDU Session Create Request message may include at least one of a PDU Session ID, S-NSSAI, and DNN. The AMF 102 according to various embodiments of the present disclosure confirms that there is a PDU session, that is, a first PDU session, concluded with the S-NSSAI requested by the terminal 100 based on the UE context stored in the AMF 102. I can. The PDU Session Create Request message may include Slice-AMBR and session-AMBR of the first PDU session stored by the AMF 102, and serving SMF of the first PDU session, that is, SMF1 200 ID information.

The SMF2 500 may create an SM Context for a second PDU session. The SM Context is a set of information for managing the PDU session requested in step 514. SM Context may be referred to as SM Context ID.

In step 516, the SMF2 500 may request the UDM 104 for subscription information of the terminal 100, and obtain the terminal subscription information from the UDM 104. The terminal subscription information may include at least one or more of subscribed S-NSSAI, subscribed Slice-AMBR for subscribed S-NSSAI, subscribed S-NSSAI and subscribed session-AMBR for DNN.

The SMF2 500 may authenticate the terminal request received in step 314 based on the terminal subscription information. For example, the SMF2 500 may check whether the S-NSSAI and/or DNN requested by the terminal included in the PDU Session Create Request message are included in the terminal subscription information.

In step 518, the SMF2 500 may return a PDU session creation response message to the AMF 102. The PDU Session Create Response message may include an SM Context ID for the second PDU session.

The AMF 102 may store the received SM Context ID. The AMF 102 may use the second SM Context ID to indicate the SM Context for the second PDU session referred to as the second PDU Session ID.

In step 520, the SMF2 500 may establish an SM policy association for the PCF 103 and the second PDU session. The PCF 103 in which the SMF2 500 establishes SM policy association may be the same as or different from the PCF 103 in which the SMF1 200 establishes policy association in the first PDU session establishment procedure. The policy association request message transmitted from the SMF2 500 to the PCF 103 is S-NSSAI for establishing a second PDU session, subscribed Slice-AMBR, serving network Slice-AMBR, subscribed session-AMBR, At least one of SUPI and HPLMN ID may be included. In this case, the subscribed Slice-AMBR may be a subscribed Slice-AMBR for S-NSSAI for a second PDU session. In addition, the serving network Slice-AMBR may be a serving network Slice-AMBR used in a serving network for a second PDU session.

In step 522, the PCF 103 may determine the authorized Slice-AMBR of the received subscribed Slice-AMBR to the serving network Slice-AMBR based on at least one of terminal subscription information and local policy. In addition, when the PCF 103 determines the authorized Slice-AMBR, a roaming agreement with the HPLMN of the terminal may be considered. Subscribed Slice-AMBR to serving network Slice-AMBR and authorized Slice-AMBR determined by the PCF 103 may be the same or different. In addition, the PCF 103 may determine the authorized session-AMBR. Authorized session-AMBR may be less than or equal to authorized Slice-AMBR. The PCF 103 may establish a policy association by transmitting a Policy Association Response message to the SMF2 500. The Policy Association Response message may include at least one of authorized Slice-AMBR and authorized session-AMBR.

The SMF2 500 may determine Slice-AMBR to be used for the first PDU session and the second PDU session. The SMF2 500 is based on at least one of Slice-AMBR and Session-AMBR of the first PDU session received in step 514, Slice-AMBR for the second PDU session received in steps 516 to 522, and session-AMBR. , Slice-AMBR can be determined. For example, the SMF2 500 may determine to use the Slice-AMBR received from the AMF 102 in step 514 for the second PDU session. According to another embodiment of the present disclosure, the SMF1 200 may newly determine the Slice-AMBR during the second PDU session establishment procedure. The SMF2 500 may determine Slice-AMBR similarly to those described in Examples 2 to 3. To describe this as an example, Slice-AMBR to be used for the first PDU session and the second PDU session may be set as the sum of the AMBR of the first PDU session and the AMBR of the second PDU session. At this time, when the sum of the AMBR of the first PDU session and the AMBR of the second PDU session is greater than the values of subscribed Slice-AMBR to serving network Slice-AMBR to authorized Slice-AMBR, the SMF1 200 corresponds to the first PDU session and Slice-AMBR to be used for the second PDU session, modified by AMF 102 or SMF1 200 based on subscribed Slice-AMBR to subscribed Slice-AMBR to Slice-AMBR to serving network Slice-AMBR to authorized Slice-AMBR You can decide to use one of them. The SMF2 500 may add Slice-AMBR to the SM context of the second PDU session of the terminal 100. In addition, the SMF2 500 may add a session-AMBR for the second PDU session to the SM context of the second PDU session of the terminal 100.

In step 524, the SMF2 500 may establish an N4 session with the UPF2 501 selected for establishing a second PDU session. The N4 Session Establishment Request message transmitted from the SMF2 500 to the UPF2 501 may include at least one of Slice-AMBR and session-AMBR for the second PDU session. The UPF2 501 may store the received Slice-AMBR and session-AMBR, and then use it to control downlink data and/or uplink data traffic.

In step 526, the UPF2 (501) may return an N4 Session Establishment Response message to the SMF2 (500).

In step 528, the SMF2 500 may transmit a Namf_Communication_N1N2MessageTransfer message to the AMF 102. Namf_Communication_N1N2MessageTransfer message is at least one of information transmitted by the SMF 500 to the AMF 102, an N2 message transmitted by the SMF 500 to the base station 101, and an N1 message transmitted by the SMF 500 to the terminal 100 The above may be included.

The information transmitted by the SMF2 500 to the AMF 102 may include at least one or more of a PDU Session ID, SM Context ID, Slice-AMBR, and session-AMBR. If the Slice-AMBR received in step 528 is different from the Slice-AMBR in which the first PDU session stored by the AMF 102 is being used, the AMF 102 is the terminal 100 stored by the AMF 102. The Slice-AMBR of the first PDU session of may be updated to the newly received Slice-AMBR.

The N2 message transmitted from the SMF1 200 to the base station 101 through the AMF 102 may include at least one of a PDU Session ID, Session-AMBR, S-NSSAI, and Slice-AMBR.

In the N1 message transmitted from the SMF1 200 to the terminal 100 through the AMF 102 and the base station 101, PDU session establishment acceptance including at least one or more of S-NSSAI, Session-AMBR, and Slice-AMBR (Session Establishment Accept) message may be included.

In step 530, the AMF 102 may return a Namf_Communication_N1N2MessageTransfer Response message to the SMF2 500.

In step 532, the AMF 102 may transmit an N2 PDU session request message to the base station 101. The N2 PDU Session Request message may include the N2 message received by the AMF 102 from the SMF 500.

The base station 101 can store the S-NSSAI and Slice-AMBR together with the received PDU Session ID, and then use it to control downlink data and/or uplink data traffic of the second PDU session. For example, the base station 101 has the sum of the uplink data traffic or downlink data traffic of the first PDU session and the uplink data traffic or/and the downlink data traffic of the second PDU session is less than the received Slice-AMBR. You can control it or the same. When uplink traffic or downlink traffic exceeding Slice-AMBR occurs, the base station 101 may discard some of the data traffic of the first PDU session and/or the second PDU session.

In step 534, the base station 101 may perform an AN-specific resource setup procedure with the terminal 100. During the AN-specific resource setup procedure, the base station 101 may transmit a PDU Session Establishment Accept message received from the AMF 102 to the terminal 100. The terminal 100 may store the received Slice-AMBR and then use it to control uplink data traffic of the PDU session associated with the S-NSSAI. For example, the terminal 100 may control the sum of the uplink data traffic of the first PDU session and the uplink data traffic of the second PDU session to be less than or equal to the received Slice-AMBR. When uplink data traffic exceeding Slice-AMBR occurs, the terminal 100 first transmits a PDU session or data traffic with a high priority, and transmits a PDU session or data traffic with a low priority later, or some data Can be thrown away.

The SMF 500 having successfully performed the second PDU session establishment procedure may register the SMF 500 itself with the UDM 104 as a serving SMF of the second PDU session in step 536. The UDM 104 may store the SMF instance ID of the SMF 500.

The terminal 100 may transmit uplink data to the DN 203 via the base station 101 and the UPF 501. Further, the DN 203 may transmit downlink data to the terminal 100 via the UPF 501 and the base station 101.

According to various embodiments of the present disclosure, the Slice-AMBR determined during the second PDU session establishment procedure may be different from the Slice-AMBR determined during the first PDU session establishment procedure. The terminal 100 and the base station 101 may use the Slice-AMBR received during the second PDU session establishment procedure in order to control uplink and/or downlink data traffic for the first PDU session. Since the UPF1 202 is not involved in the second PDU session, it may be necessary to update the Slice-AMBR information of the UPF1 202. Accordingly, the AMF 102 to the SMF2 500 may perform a Slice-AMBR update procedure of the first PDU session being used by the terminal 100, the base station 101, and the UPF1 202.

For example, the AMF 102 may compare the Slice-AMBR for the S-NSSAI received in step 528 with the Slice-AMBR for the S-NSSAI stored by the AMF 102. If the Slice-AMBR for the S-NSSAI received in step 528 and the Slice-AMBR for the S-NSSAI stored by the AMF 102 are different, the AMF 102 determines the Slice-AMBR of the first PDU session. It may be determined to change to the latest Slice-AMBR value, that is, the Slice-AMBR received in step 528. Accordingly, the AMF 102 may transmit the latest Slice-AMBR value to the SMF1 200 serving SMF of the first PDU session in step 548a.

According to another embodiment of the present disclosure, after determining the Slice-AMBR of the second PDU session, the SMF2 500 determines the Slice-AMBR for the S-NSSAI received in step 514 and the Slice-AMBR newly determined by the SMF2 500. AMBR can be compared. If the Slice-AMBR for the S-NSSAI received in step 514 and the Slice-AMBR determined by the SMF2 500 are different, the SMF2 500 sets the Slice-AMBR of the first PDU session to the latest Slice-AMBR value, That is, after step 514, it may be determined to change to Slice-AMBR determined to be used for the second PDU session. Accordingly, the SMF2 500 may transmit the latest Slice-AMBR value to the SMF1 200 in step 548b by using the serving SMF information of the first PDU session received in step 514.

Upon receiving the latest Slice-AMBR, the SMF1 200 may determine to update the Slice-AMBR of the first PDU session in step 350. The SMF1 200 may perform step 360 in step 350 described in FIGS. 3A and 3B. The terminal 100, the base station 101, and the UPF1 202 may control uplink and/or downlink data traffic using the updated Slice-AMBR for the first PDU session.

[Example 5]

After establishing a PDU session for S-NSSAI through the procedure shown in FIG. 2, a terminal according to various embodiments of the present disclosure may transmit and receive DN and uplink and downlink data traffic. In addition, the terminal according to various embodiments of the present disclosure may establish another PDU session for the same S-NSSAI. For example, a first PDU session may be established to communicate with DN1 (203), and a second PDU session may be established to communicate with DN2 (300). At this time, since the first PDU session and the second PDU session are associated with the same S-NSSAI, in the 5G system, the sum of the uplink and downlink data traffic of the first PDU session and the second PDU session is S-NSSAI. It should be able to control less than or equal to the total sum of Slice-AMBR linked to.

Embodiment 5 describes a method of managing Slice-AMBR for S-NSSAI of a first PDU session and a second PDU session in UDM, and controlling the total sum of uplink and downlink data traffic. According to the method described in Embodiment 5, the SMF and/or UPF for the first PDU session and the SMF and/or UPF for the second PDU session may be different.

The fifth embodiment will also be described using the PDU Session Establishment procedure of FIGS. 5A and 5B described above.

5A and 5B, the UE 100 establishes a first PDU session for S-NSSAI as shown in FIG. 2, and transmits DN1 203 and uplink data and/or downlink data traffic. You can give and receive. The terminal 100, the base station 101, and the UPF1 202 may store Slice-AMBR for S-NSSAI and control the data rate of uplink data and/or downlink data traffic.

During the first PDU session establishment procedure, the Registration message transmitted by the SMF1 200 to the UDM 104 in step 236 may include Slice-AMBR information and session-AMBR information used by the first PDU session for S-NSSAI. have. The UDM 104 may store such Slice-AMBR information and session-AMBR information as SM data of the terminal.

Terminal 100 according to various embodiments of the present disclosure, based on at least one of a terminal policy (UE Policy) of the terminal and local configuration information (local configuration), for the S-NSSAI associated with the first PDU session It may be determined to establish another PDU session, that is, a second PDU session.

In step 510, the terminal 100 may transmit a PDU Session Establishment Request message to establish a second PDU session. The PDU Session Establishment Request message may include at least one of a PDU Session ID, an S-NSSAI intended to be used by the terminal 100, and a DNN. In this case, the S-NSSAI included in the PDU Session Establishment Request may be the same as the S-NSSAI for the first PDU session. In addition, the DNN included in the PDU Session Establishment Request may be the same as or different from the DNN for the first PDU session.

In step 512, the AMF 102 may select an SMF capable of managing a PDU session requested by the terminal 100. For example, the AMF 102 may select an SMF that supports the S-NSSAI and/or DNN requested by the terminal 100. According to various embodiments of the present disclosure, the SMF selected by the AMF 102 may be different from the serving SMF1 200 of the first PDU session.

In step 514, the AMF 102 may transmit a PDU Session Create Request message to the selected SMF2 500. The PDU Session Create Request message may include at least one of a PDU Session ID, S-NSSAI, and DNN.

The SMF2 500 may create an SM Context for a second PDU session. The SM Context is a set of information for managing the PDU session requested in step 514. SM Context may be referred to as SM Context ID.

In step 516, the SMF2 500 may request the UDM 104 for subscription information of the terminal 100, and obtain the terminal subscription information from the UDM 104. The terminal subscription information may include at least one or more of subscribed S-NSSAI, subscribed Slice-AMBR for subscribed S-NSSAI, subscribed S-NSSAI and subscribed session-AMBR for DNN. The UDM 104 according to various embodiments of the present disclosure transmits information related to a first PDU session of the terminal (eg, Slice-AMBR and/or session-AMBR, etc. being used in the first PDU session) to the SMF2 500 Can be provided to.

The SMF2 500 may authenticate the terminal request received in step 314 based on the terminal subscription information. For example, the SMF2 500 may check whether the S-NSSAI and/or DNN requested by the terminal included in the PDU Session Create Request message are included in the terminal subscription information.

In step 518, the SMF2 500 may return a PDU Session Create Response message to the AMF 102. The PDU Session Create Response message may include an SM Context ID for the second PDU session.

The AMF 102 may store the received SM Context ID. The AMF 102 may use the second SM Context ID to indicate the SM Context for the second PDU session referred to as the second PDU Session ID.

In step 520, the SMF2 500 may establish an SM policy association for the PCF 103 and the second PDU session. The PCF 103 in which the SMF 2500 establishes SM policy association may be the same as or different from the PCF 103 in which the SMF1 200 establishes policy association in the first PDU session establishment procedure. In the Policy Association Request message transmitted from the SMF2 500 to the PCF 103, among S-NSSAI, subscribed Slice-AMBR, serving network Slice-AMBR, subscribed session-AMBR, SUPI, and HPLMN ID for establishing a second PDU session. At least one may be included. In this case, the subscribed Slice-AMBR may be a subscribed Slice-AMBR for S-NSSAI for a second PDU session. In addition, the serving network Slice-AMBR may be a serving network Slice-AMBR used in a serving network for a second PDU session.

In step 522, the PCF 103 may determine the authorized Slice-AMBR of the received subscribed Slice-AMBR to the serving network Slice-AMBR based on at least one of terminal subscription information and local policy. In addition, when the PCF 103 determines the authorized Slice-AMBR, a roaming agreement with the HPLMN of the terminal may be considered. Subscribed Slice-AMBR to serving network Slice-AMBR and authorized Slice-AMBR determined by the PCF 103 may be the same or different. In addition, the PCF 103 may determine the authorized session-AMBR. Authorized session-AMBR may be less than or equal to authorized Slice-AMBR. The PCF 103 may establish a policy association by transmitting a Policy Association Response message to the SMF2 500. The Policy Association Response message may include at least one of authorized Slice-AMBR and authorized session-AMBR.

The SMF2 500 may determine Slice-AMBR to be used for the first PDU session and the second PDU session. SMF2 (500) is the first PDU session received in step 516 is currently used Slice-AMBR and the currently used Session-AMBR, Slice-AMBR and session-AMBR for the second PDU session received in steps 516 to 522 Slice-AMBR may be determined based on at least one of them. For example, the SMF2 500 may determine to use the Slice-AMBR currently being used by the first PDU session received from the UDM 104 for the second PDU session in step 516. Alternatively, the SMF2 500 may newly determine Slice-AMBR during the second PDU session establishment procedure. The SMF2 500 may determine Slice-AMBR similarly to those described in Examples 2 to 3. For example, Slice-AMBR to be used for the first PDU session and the second PDU session may be set as the sum of the AMBR of the first PDU session and the AMBR of the second PDU session. At this time, when the sum of the AMBR of the first PDU session and the AMBR of the second PDU session is greater than the values of subscribed Slice-AMBR to serving network Slice-AMBR to authorized Slice-AMBR, the SMF1 200 corresponds to the first PDU session and Slice-AMBR to be used for the second PDU session, modified by AMF 102 or SMF1 200 based on subscribed Slice-AMBR to subscribed Slice-AMBR to Slice-AMBR to serving network Slice-AMBR to authorized Slice-AMBR You can decide to use one of them. The SMF2 500 may add Slice-AMBR to the SM context of the second PDU session of the terminal 100. In addition, the SMF2 500 may add a session-AMBR for the second PDU session to the SM context of the second PDU session of the terminal 100.

From steps 524 to 526, the method described in Example 4 is followed.

In step 528, the SMF2 500 may transmit a Namf_Communication_N1N2MessageTransfer message to the AMF 102. In the Namf_Communication_N1N2MessageTransfer message, at least one of information transmitted by the SMF2 500 to the AMF 102, an N2 message transmitted by the SMF 2500 to the base station 101, and an N1 message transmitted by the SMF2 500 to the terminal 100 The above may be included.

The information transmitted by the SMF2 500 to the AMF 102 may include at least one or more of a PDU Session ID, SM Context ID, Slice-AMBR, and session-AMBR.

The N2 message transmitted from the SMF2 500 to the base station 101 through the AMF 102 may include at least one of a PDU Session ID, Session-AMBR, S-NSSAI, and Slice-AMBR.

In the N1 message transmitted from the SMF2 500 to the terminal 100 through the AMF 102 and the base station 101, a PDU Session Establishment Accept message including at least one of S-NSSAI, Session-AMBR, and Slice-AMBR is included. Can be included.

In step 530, the AMF 102 may return a Namf_Communication_N1N2MessageTransfer Response message to the SMF2 500.

From steps 532 to 534, the method described in Example 4 is followed.

The SMF2 500 having successfully performed the second PDU session establishment procedure may register the SMF2 500 itself with the UDM 104 as a serving SMF of the second PDU session in step 536. According to various embodiments of the present disclosure, the SMF2 500 may include the latest Slice-AMBR determined to be used for S-NSSAI in a Registration message. According to various embodiments of the present disclosure, the UDM 104 may store the SMF instance ID of the SMF2 500 and may store the latest Slice-AMBR currently being used for S-NSSAI.

According to various embodiments of the present disclosure, the Slice-AMBR determined during the second PDU session establishment procedure may be different from the Slice-AMBR determined during the first PDU session establishment procedure. The terminal 100 and the base station 101 may use the Slice-AMBR received during the second PDU session establishment procedure in order to control uplink and/or downlink data traffic for the first PDU session. Since the UPF1 202 is not involved in the second PDU session, it may be necessary to update the Slice-AMBR information of the UPF1 202. Accordingly, the UDM 104 may perform a Slice-AMBR update procedure of the first PDU session being used by the terminal 100, the base station 101, and the UPF1 202.

For example, the UDM 104 may compare Slice-AMBR for S-NSSAI received in step 536 with Slice-AMBR for S-NSSAI stored by UDM 104. If the Slice-AMBR for the S-NSSAI received in step 536 and the Slice-AMBR for the S-NSSAI stored by the UDM 104 are different, the UDM 104 determines the Slice-AMBR of the first PDU session. It may be determined to change to the latest Slice-AMBR value, that is, the Slice-AMBR received in step 536. Accordingly, the UDM 104 may transmit the latest Slice-AMBR value to the SMF1 200, which is the serving SMF of the first PDU session, in step 548c.

Upon receiving the latest Slice-AMBR, the SMF1 200 may determine to update the Slice-AMBR of the first PDU session in step 350. The SMF1 200 may perform step 360 in step 350 described in FIGS. 3A and 3B. The terminal 100, the base station 101, and the UPF 202 may control uplink and/or downlink data traffic using the updated Slice-AMBR for the first PDU session.

[Example 6]

After establishing a PDU session for S-NSSAI through the procedure shown in FIG. 2, a terminal according to various embodiments of the present disclosure may transmit and receive DN and uplink and downlink data traffic. In addition, the terminal according to various embodiments of the present disclosure may establish another PDU session for the same S-NSSAI. For example, a first PDU session may be established to communicate with DN1 (203), and a second PDU session may be established to communicate with DN2 (300). At this time, since the first PDU session and the second PDU session are associated with the same S-NSSAI, in the 5G system, the sum of the uplink and downlink data traffic of the first PDU session and the second PDU session is S-NSSAI. It should be able to control less than or equal to the total sum of Slice-AMBR linked to.

Embodiment 6 is in selecting the PCF for the second PDU session, selecting the same PCF as the first PDU session, and managing Slice-AMBR for the S-NSSAI of the first PDU session and the second PDU session in this PCF And, a method of controlling the total sum of uplink and downlink data traffic will be described. According to the method described in Embodiment 6, the SMF and/or UPF for the first PDU session and the SMF and/or UPF for the second PDU session may be different.

Embodiment 6 will also be described using the PDU Session Establishment procedure of FIGS. 5A and 5B described above.

5A and 5B, the UE 100 establishes a first PDU session for S-NSSAI as shown in FIG. 2, and transmits DN1 203 and uplink data and/or downlink data traffic. You can give and receive. The terminal 100, the base station 101, and the UPF 202 may store Slice-AMBR for S-NSSAI and control the data rate of uplink data and/or downlink data traffic.

During the first PDU session establishment procedure, in the Namf_Communication_N1N2MessageTransfer message transmitted by the SMF1 200 to the AMF 102 in step 328, the PCF information that the SMF1 200 establishes policy association for the first PDU session, that is, PCF 103 ID may be included. The AMF 102 may store such PCF 103 ID information in the UE context.

Terminal 100 according to various embodiments of the present disclosure, based on at least one of a terminal policy (UE Policy) of the terminal and local configuration information (local configuration), for the S-NSSAI associated with the first PDU session It may be determined to establish another PDU session, that is, a second PDU session.

In step 510, the terminal 100 may transmit a PDU Session Establishment Request message to establish a second PDU session. The PDU Session Establishment Request message may include at least one of a PDU Session ID, an S-NSSAI intended to be used by the terminal 100, and a DNN. In this case, the S-NSSAI included in the PDU Session Establishment Request may be the same as the S-NSSAI for the first PDU session. In addition, the DNN included in the PDU Session Establishment Request may be the same as or different from the DNN for the first PDU session.

In step 512, the AMF 102 may select an SMF capable of managing a PDU session requested by the terminal 100. For example, the AMF 102 may select an SMF that supports the S-NSSAI and/or DNN requested by the terminal 100. According to various embodiments of the present disclosure, the SMF selected by the AMF 102 may be different from the serving SMF1 200 of the first PDU session.

In step 514, the AMF 102 may transmit a PDU Session Create Request message to the selected SMF 500. The PDU Session Create Request message may include at least one of a PDU Session ID, S-NSSAI, and DNN. The AMF 102 according to various embodiments of the present disclosure confirms that there is a PDU session, that is, a first PDU session, concluded with the S-NSSAI requested by the terminal 100 based on the UE context stored in the AMF 102. I can. The PDU Session Create Request message may include PCF ID information of the first PDU session stored by the AMF 102.

The SMF2 500 may create an SM Context for a second PDU session. The SM Context is a set of information for managing the PDU session requested in step 514. SM Context may be referred to as SM Context ID.

In step 516, the SMF2 500 may request the UDM 104 for subscription information of the terminal 100, and obtain the terminal subscription information from the UDM 104. The terminal subscription information may include at least one or more of subscribed S-NSSAI, subscribed Slice-AMBR for subscribed S-NSSAI, subscribed S-NSSAI and subscribed session-AMBR for DNN.

The SMF2 500 may authenticate the terminal request received in step 314 based on the terminal subscription information. For example, the SMF2 500 may check whether the S-NSSAI and/or DNN requested by the terminal included in the PDU Session Create Request message are included in the terminal subscription information.

In step 518, the SMF 500 may return a PDU Session Create Response message to the AMF 102. The PDU Session Create Response message may include an SM Context ID for the second PDU session.

The AMF 102 may store the received SM Context ID. The AMF 102 may use the second SM Context ID to indicate the SM Context for the second PDU session referred to as the second PDU Session ID.

In step 520, the SMF2 500 may establish an SM policy association for the PCF and the second PDU session. SMF2 (500), using the PCF ID information of the first PDU session received in step 514, the PCF to establish the SM policy association for the second PDU session, select the same PCF (103) as the first PDU session I can. In the Policy Association Request message transmitted from the SMF2 500 to the PCF 103, among S-NSSAI, subscribed Slice-AMBR, serving network Slice-AMBR, subscribed session-AMBR, SUPI, and HPLMN ID for establishing a second PDU session. At least one may be included. In this case, the subscribed Slice-AMBR may be a subscribed Slice-AMBR for S-NSSAI for a second PDU session. In addition, the serving network Slice-AMBR may be a serving network Slice-AMBR used in a serving network for a second PDU session.

In step 522, the PCF 103 may determine the authorized Slice-AMBR of the received subscribed Slice-AMBR to the serving network Slice-AMBR based on at least one of terminal subscription information and local policy. In order to determine the authorized Slice-AMBR, the PCF 103 according to various embodiments of the present disclosure may consider not only the information received in step 520 but also the Slice-AMBR currently being used by the first PDU session. In addition, when the PCF 103 determines the authorized Slice-AMBR, a roaming agreement with the HPLMN of the terminal may be considered. Subscribed Slice-AMBR to serving network Slice-AMBR and authorized Slice-AMBR determined by the PCF 103 may be the same or different. In addition, the PCF 103 may determine the authorized session-AMBR. Authorized session-AMBR may be less than or equal to authorized Slice-AMBR. The PCF 103 may establish a policy association by transmitting a Policy Association Response message to the SMF2 500. The Policy Association Response message may include at least one of authorized Slice-AMBR and authorized session-AMBR. The authorized Slice-AMBR to the authorized session-AMBR newly determined by the PCF 103 may be the same as or different from the Slice-AMBR to the session-AMBR currently being used in the first PDU session.

The SMF2 500 may determine a Slice-AMBR to be used for the second PDU session. The SMF 500 may determine Slice-AMBR based on at least one of Slice-AMBR and session-AMBR for the second PDU session received in steps 516 to 522. For example, the SMF2 500 may determine to use the Slice-AMBR received from the PCF 103 in step 522 for the second PDU session. The SMF2 500 may add Slice-AMBR to the SM context of the second PDU session of the terminal 100. In addition, the SMF2 500 may add a session-AMBR for the second PDU session to the SM context of the second PDU session of the terminal 100.

From steps 524 to 534, the method described in Example 5 is followed.

Step 536 follows the method described in Example 4.

According to various embodiments of the present disclosure, the Slice-AMBR determined during the second PDU session establishment procedure may be different from the Slice-AMBR determined during the first PDU session establishment procedure. The terminal 100 and the base station 101 may use the Slice-AMBR received during the second PDU session establishment procedure in order to control uplink and/or downlink data traffic for the first PDU session. Since the UPF 202 is not involved in the second PDU session, it may be necessary to update Slice-AMBR information of the UPF 202. Accordingly, the PCF 103 may perform a Slice-AMBR update procedure of the first PDU session being used by the terminal 100, the base station 101, and the UPF 202.

For example, the PCF 103 may transmit the latest Slice-AMBR determined in steps 520 to 522 and the latest Slice-AMBR value to the SMF1 200 serving SMF of the first PDU session in step 548d. .

Upon receiving the latest Slice-AMBR, the SMF1 200 may determine to update the Slice-AMBR of the first PDU session in step 350. The SMF1 200 may perform step 360 in step 350 described in FIGS. 3A and 3B. The terminal 100, the base station 101, and the UPF1 202 may control uplink and/or downlink data traffic using the updated Slice-AMBR for the first PDU session.

[Example 7]

A terminal according to various embodiments of the present disclosure may establish a PDU session and exchange data with a DN in a connected state. Such a terminal can perform a state change to an idle state, and the 5G system can release a radio resource between the terminal and the base station while maintaining the PDU session in a deactivate state. .

Embodiment 7 describes a method of setting Slice-AMBR related to the PDU session to a terminal, a base station, and a 5G NF in a procedure for converting a PDU session to an activated state.

6 illustrates a service request procedure according to an embodiment of the present disclosure.

Prior to the description with reference to FIG. 6, the terminal (UE) 100 and network entities will be described. The terminal 100 is located within a specific base station (RAN) 101 and may communicate with the base station 101 by establishing a radio channel. As described above, the base station 101 may be a base station of a 5G network, an LTE or LTE-A base station, or may be a network entity that performs a role of a base station in other wireless communication networks. Hereinafter, for convenience of explanation, the base station 101 is assumed to be a 5G base station and the mobile communication system is a 5G wireless communication network. In addition, the 5G core network excluding the base station 101 will be described on the assumption that the AMF 102, the PCF 103, the SMF1 200, and the SMF2 500 are included. A portion indicated by a dotted line in FIG. 6 described below may be a procedure that can be omitted.

Referring to FIG. 6, downlink data traffic may be generated from a DN. In this case, when the corresponding PDU session is in an inactive state, the network may transmit a paging message or a NAS notification message to the terminal 100 in step 610. Upon receiving the paging message or/and the NAS notification message, the terminal 100 may transmit a service request message in step 612. Alternatively, in order for the terminal 100 in the idle state to transmit uplink data traffic, it may transmit a Service Request message in step 612. The Service Request message may include at least one or more of List of PDU Sessions To Be Activated and List of Allowed PDU Sessions. List of PDU Sessions To Be Activated and/or List of Allowed PDU Sessions may include one or more PDU session information to which the UE and/or DN intends to transmit data.

In step 614, the base station 101 may transmit the received Service Request message to the AMF 102. The AMF 102 may select a PDU session to switch to the activated state based on the received List of PDU Sessions To Be Activated and/or List of Allowed PDU Sessions. For example, the AMF 102 may determine to switch the first PDU session and the second PDU session to the active state according to various embodiments of the present disclosure. The AMF 102 may determine that the first PDU session and the second PDU session are associated with the same S-NSSAI.

In steps 620 and 630, the AMF 102 may transmit an Nsmf_PDUSession_UpdateSMContext Request message to the serving SMF of the PDU session to be switched to the active state. For example, the AMF 102 determines to switch the first PDU session and the second PDU session to the active state according to an embodiment of the present disclosure, and the SMF1 200 and the serving SMF of the first PDU session 2 An Nsmf_PDUSession_UpdateSMContext Request message may be transmitted to the SMF2 500, which is a serving SMF of the PDU session. The Nsmf_PDUSession_UpdateSMContext Request message may include Slice-AMBR information for the S-NSSAI associated with the PDU session.

In steps 622 to 632, the SMF1 200 and the SMF2 500 may perform a policy linkage modification procedure with the PCF 103, respectively. The PCF 103 may provide Slice-AMBR information for the S-NSSAI associated with the PDU session to the SMF1 200 and SMF2 500 in the message.

In steps 624 to 634, the SMF1 200 and the SMF2 500 may select a UPF for the first PDU session or/and the second PDU session, and perform an N4 session establishment to an N4 session modification procedure. The SMF1 200 or/and the SMF2 500 may transmit Slice-AMBR information for each PDU session to the UPF. The Slice-AMBR information may be a Slice-AMBR value obtained in steps 620 to 622 or/and 630 to 632, or a Slice-AMBR value determined by SMF.

In steps 626 to 636, the SMF1 200 and the SMF2 500 may each return an Nsmf_PDUSession_UpdateSMContext Response message to the AMF 102. The Nsmf_PDUSession_UpdateSMContext Response message may include Slice-AMBR information for S-NSSAI associated with each PDU session.

In step 640, the AMF 102 may transmit an N2 message to the base station 101. The N2 message may include information related to a PDU session activated by a service request procedure. For example, S-NSSAI information associated with an activated PDU session may be included. In addition, Slice-AMBR information associated with each S-NSSAI may be included. For example, when a first PDU session and a second PDU session are activated due to a service request procedure, Slice-AMBR may be set as the sum of AMBRs of the first PDU session and the second PDU session. Alternatively, session-AMBR information associated with each PDU session may be included.

The base station 101 may store information received from the AMF 102 and then use it to control uplink and downlink data traffic. For example, the base station 101 may store the received S-NSSAI and Slice-AMBR associated with the S-NSSAI. According to another embodiment of the present disclosure, the base station 101 may calculate and store Slice-AMBR for S-NSSAI based on the received session-AMBR.

In step 642, the base station 101 may perform an RRC connection reconfiguration procedure with the terminal 100. In this case, the base station 101 may transmit the Service Accept message received from the AMF 102 to the terminal 100 in step 640. The Service Accept message may include information related to a PDU session activated by a service request procedure. For example, S-NSSAI information associated with an activated PDU session may be included. In addition, Slice-AMBR information associated with each S-NSSAI may be included. For example, when a first PDU session and a second PDU session are activated due to a service request procedure, Slice-AMBR may be set as the sum of AMBRs of the first PDU session and the second PDU session. Alternatively, session-AMBR information associated with each PDU session may be included.

The terminal 100 may store information received from the base station 101 and then use it to control uplink and downlink data traffic. For example, the terminal 100 may store the received S-NSSAI and Slice-AMBR associated with the S-NSSAI. Alternatively, the terminal 100 may calculate and store Slice-AMBR for S-NSSAI based on the received session-AMBR.

7 illustrates a UE Configuration Update procedure according to an embodiment of the present disclosure.

Prior to the description with reference to FIG. 7, the terminal (UE) 100 and network entities will be described. The terminal 100 is located within a specific base station (RAN) 101 and may communicate with the base station 101 by establishing a radio channel. As described above, the base station 101 may be a base station of a 5G network, an LTE or LTE-A base station, or may be a network entity that performs a role of a base station in other wireless communication networks. Hereinafter, for convenience of explanation, the base station 101 is assumed to be a 5G base station and the mobile communication system is a 5G wireless communication network. In addition, the 5G core network excluding the base station 101 will be described on the assumption that the AMF 102, the PCF 103, the SDF1 200, and the UDM 104 are included.

Referring to FIG. 7, in step 710, the 5G core network may change Slice-AMBR associated with S-NSSAI. For example, UDM 104 may change Slice-AMBR due to the change of terminal subscription information. Or, for example, due to policy information change, the PCF 103 may change Slice-AMBR. Alternatively, for example, SMF1 200 to AMF 102 may change Slice-AMBR due to a change in the state of the PDU session.

In step 720, the AMF 102 may transmit the changed information to the terminal 100. For example, the AMF 102 may transmit S-NSSAI and Slice-AMBR information associated with the S-NSSAI.

The terminal 100 may store the received information and then use it to control uplink data traffic of the PDU session associated with the S-NSSAI.

In step 722, the AMF 102 may transmit the changed information to the base station 101. For example, the AMF 102 may transmit a terminal ID, S-NSSAI and Slice-AMBR information associated with the S-NSSAI.

The base station 101 may store the received information and then use it to control uplink or downlink data traffic of the PDU session associated with the S-NSSAI.

[Example 8]

10 illustrates a PDU session establishment procedure according to various embodiments of the present disclosure.

In step 1001, the UE may transmit a PDU Session Establishment Request message to the AMF. The PDU Session Establishment Request message may include S-NSSAI, which is network slice information that the UE intends to use.

In step 1002, the AMF may select an SMF that supports the S-NSSAI received in step 1001. If, the AMF, based on at least one of the local policy of the AMF, the slice policy obtained from the PCF (slice policy), the terminal subscription data obtained from the UDM (UE subscription data), all for S-NSSAI It may be determined whether the PDU session should be supported by the same SMF or SMF (SMF within the same SMF set) belonging to the same SMF set. If all sessions for S-NSSAI are to be supported by the same SMF or SMF belonging to the same SMF set, the AMF may select the same SMF for the S-NSSAI or the SMF belonging to the same SMF set. For example, if the AMF has not previously selected the SMF for the S-NSSAI, it may select a new SMF. According to another embodiment, the AMF has previously selected SMF for the S-NSSAI or has a history of selecting SMF, and previously selected SMF information (eg, SMF ID, SMF instance ID, SMF Set ID, etc.) If stored, the SMF corresponding to the previously selected and stored information (e.g., the same SMF (the same SMF) as the previously selected SMF), another SMF belonging to the SMF set to which the previously selected SMF belongs (a SMF within the same SMF set), etc.) and subsequent procedures. According to another embodiment, the AMF is SMF information (e.g., SMF ID, SMF) that supports the S-NSSAI obtained from NRF, PCF to UDM (e.g., SMF information included in SMF Selection Subscription data). Instance ID, SMF Set ID, etc.), and SMF corresponding to the received information (e.g., SMF ID or SMF referred to by SMF instance ID, SMF belonging to SMF Set referred to by SMF Set ID, etc.) and thereafter You can proceed with the procedure.

SMFs belonging to the same SMF set according to an embodiment of the present disclosure may share PDU session-related information (eg, SM context) managed by each SMF with each other.

In step 1003, the AMF may transmit a PDU Session Create Request message to the SMF selected in step 1002. The PDU Session Create Request message may include S-NSSAI information.

In step 1004, the SMF may receive terminal subscription information (eg, UE subscription data, Session Management Subscription data, etc.) from the UDM. The terminal subscription information may include subscribed-Slice-AMBR per S-NSSAI (per S-NSSAI). If the terminal has previously established a PDU session with the same S-NSSAI and is currently using it, the SMF stores the PDU session information established by the terminal and currently being used, or the terminal establishes and uses the PDU session information that is currently being used. If it can be obtained from the SMF, the SMF may omit step 1004. Subscribed-Slice-AMBR may be a sum of a guaranteed bit rate (Guaranteed Bit Rate, GBR, or GBR QoS Flows) and a non-guaranteed bit rate (Non-GBR (Guaranteed Bit Rate), or Non-GBR QoS Flows) or, Subscribed-Slice-AMBR may be a value including only Non-GBR (or Non-GBR QoS Flows).

In step 1005, the SMF can establish a policy association with the PCF. The SMF may transmit at least one of subscribed-Slice-AMBR and Subscribed-Session-AMBR of the terminal to the PCF in step 1005. The PCF may determine the authorized-Slice-AMBR based on at least one of information received from the SMF, a local policy of a mobile communication service provider, terminal subscription information, and a roaming agreement.

For example, the PCF considers the data usage (bit rate) being used in the GBR (Guaranteed Bit Rate) QoS flows linked to the S-NSSAI being used by the UE, and is used for non-GBR QoS flows. The authorized-Slice-AMBR can be determined. When the UE is using/requesting more than one PDU session with S-NSSAI, the PCF may determine the authorized-Slice-AMBR in consideration of the GBR QoS flow included in all PDU sessions.

The PCF may transmit the authorized-Slice-AMBR determined as described in the above method to the SMF.

If the UE has previously established and is using a PDU session with the same S-NSSAI, and the SMF can store or obtain PDU session information established and used by the UE, the SMF may omit step 1005.

In step 1006, the SMF may determine a Slice-AMBR for the S-NSSAI based on information received from the AMF in step 1003, information received from the UDM in step 1004, and information received from the PCF in step 1005.

For example, SMF refers to Slice-AMBR for non-GBR QoS flow as the sum of Session-AMBR values of all PDU sessions with active user plane associated with S-NSSAI. Can be set. In addition, the SMF can be set so that the Slice-AMBR value does not exceed the subscribed-Slice-AMBR value. That is, for example, if the sum of Session-AMBR values of all PDU sessions with active user planes linked to S-NSSAI is greater than subscribed-Slice-AMBR value or authorized-Slice-AMBR, SMF is non-GBR Slice-AMBR for QoS flow can be set to subscribed-Slice-AMBR value or authorized-Slice-AMBR value.

For example, the SMF may determine the Slice-AMBR for the non-GBR QoS flow in consideration of the GBR QoS flow included in the PDU session associated with the S-NSSAI. If subscribed-Slice-AMBR received from UDM is 100 Mbps (Mega bit per second) and GBR QoS flow uses 60 Mbps, SMF uses Slice-AMBR for non-GBR QoS flow, and all subscribed-Slice- The AMBR can be set to a value excluding the GBR QoS flow, that is, 40 Mbps, for example.

As another example, the SMF may determine the Slice-AMBR for the non-GBR QoS flow in consideration of the GBR QoS flow of all PDU sessions being used/requested by the terminal associated with the S-NSSAI. If the subscribed-Slice-AMBR received from UDM is 100 Mbps (Mega bit per second), the GBR QoS flow of the first PDU session using S-NSSAI uses 40 Mbps, and the second PDU uses the same S-NSSAI If the GBR QoS flow of the session is using 35 Mbps, the SMF excludes the GBR QoS flow of all PDU sessions from Slice-AMBR for non-GBR QoS flow and all subscribed-Slice-AMBR, that is, for example, It can be set to 25 Mbps.

Looking at another example, the terminal accesses the AMF through a 3GPP access network (AN) (eg, NR, E-UTRA, etc.) to request/establish a PDU session for S-NSSAI, and , It is possible to request/establish a PDU session for S-NSSAI by accessing the AMF through a non-3GPP access network (eg, WiFi, etc.). That is, the UE may use a PDU session for S-NSSAI through a 3GPP access network, and use a PDU session for the same S-NSSAI through a non-3GPP access network. The AMF may include the access network information of the terminal in the message transmitted to the SMF in step 1003. The SMF may know the access network of the requested PDU session based on the information received in step 1003. The SMF can divide Slice-AMBR into a value that can be used in a 3GPP access network and a value that can be used in a non-3GPP access network. For example, when Slice-AMBR is 40 Mbps, SMF sets a Slice-AMBR value that can be used in a 3GPP access network to 30 Mbps, and a Slice-AMBR value that can be used in a non-3GPP access network is previously sliced. It can be set to a value excluding values that can be used by the 3GPP access network from the -AMBR value, that is, 10 Mbps.

In step 1007, the SMF may transmit the Slice-AMBR value determined in step 1006 to the AMF. In this case, the Slice-AMBR value transmitted by the SMF may be a different value according to the type of the access network (eg, a 3GPP access network or a non-3GPP access network). Alternatively, the Slice-AMBR value transmitted by the SMF may be the same value regardless of the type of the access network.

In step 1008, the AMF may transmit the Slice-AMBR value received from the SMF in step 1007 to the base station.

In step 1009, the base station may apply the received Slice-AMBR (Slice-AMBR enforcement). For example, the base station may control the sum of the maximum uplink data rate (maximum uplink data throughput) of one or more non-GBR QoS flows associated with the S-NSSAI up to the value of Slice-AMBR. . In addition, the base station may control the sum of the maximum downlink data rate (maximum downlink data throughput) of one or more non-GBR QoS flows associated with the S-NSSAI up to the value of Slice-AMBR.

In step 1010, the base station may transmit a PDU Session Establishment Accept message received from the AMF in step 1008 to the terminal.

When Slice-AMBR is included in the PDU Session Establishment Accept message, the UE can control the sum of the maximum uplink data rates of non-GBR QoS flows of all PDU sessions associated with S-NSSAI up to the Slice-AMBR value. .

[Example 9]

The AMF 120 according to an embodiment of the present disclosure may select an SMF supporting S-NSSAI in step 212 of FIG. 2, step 312 of FIG. 3, step 512 of FIG. 5, or step 1002 of FIG. 10.

In the method for the AMF 120 to select the SMF, the AMF 120 may determine the SMF selection method based on subscription data received from the UDM 104 in step 116 of FIG. 1. The subscription data may include SMF selection subscription data. The SMF selection subscription data may include information (eg, an indicator, etc.) indicating whether the same SMF should be selected for multiple PDU sessions associated with the same S-NSSAI.

The AMF 120 according to an embodiment of the present disclosure includes steps 212 of FIG. 2, steps 312 of FIG. 3, and steps of FIG. 5 among the PDU session establishment procedures illustrated in FIGS. 2, 3, 5 or 10 described above. In step 512 or step 1002 of FIG. 10, it may be checked whether the SMF selection subscription data received in step 116 of FIG. 1 indicates selection of the same SMF for a plurality of PDU sessions.

According to an embodiment of the present disclosure, when SMF selection subscription information indicates the same SMF selection for a plurality of PDU sessions, step 212 of FIG. 2, step 312 of FIG. 3, step 512 of FIG. 5, or In step 1002 of FIG. 10, the AMF 120 may check whether the SMF for the S-NSSAI requested to establish a PDU session has been previously selected.

If there is an SMF previously selected and stored by the AMF for the S-NSSAI, the AMF may select the stored SMF. Through this method, the AMF can use the same SMF for multiple PDU sessions (or additional PDU sessions) for the S-NSSAI.

If there is no SMF previously selected for the S-NSSAI, the AMF may newly select the SMF. AMF can store newly selected SMF information.

According to an embodiment of the present disclosure, when SMF selection subscription information does not indicate the same SMF selection for a plurality of PDU sessions, step 212 of FIG. 2, step 312 of FIG. 3, step 512 of FIG. 5 Alternatively, in step 1002 of FIG. 10, the AMF 120 may newly select the SMF. AMF can store newly selected SMF information.

8 is an internal functional block diagram of an NF according to various embodiments of the present disclosure.

Prior to describing FIG. 8, NF is any of the AMF 102, PCF 103, UDM 104, SMF1 200, SMF2 500, UPF1 202, and UPF2 400 described in the present disclosure. Can be one.

Referring to FIG. 8, the network interface 810 may communicate with other network entities of the core network. For example, when the NF is the AMF 102, communication may be performed with the SMF1 200, the SMF2 500, the PCF 103, and the like. As another example, when the NF is the PCF 103, communication may be performed with the AMF 102, the UDM 104, the SMF1 200, and the like. Similarly, when the NF is a specific network entity, the network interface 810 may communicate with other entities of the core network.

The control unit 811 may be implemented as at least one processor or/and a program for performing the operation of the NF. For example, when the NF is the AMF 102, the controller 811 may perform the operation of the AMF 102 described above. As another example, when the NF is the PCF 103, the above-described operation of the PCF 103 may be performed. In the case of other network entities, it is possible to perform the control necessary for the above-described operation in the same manner.

The memory 812 may store programs required by the controller 811 and various types of control information, as well as each information described in the present disclosure. For example, when the NF is the AMF 102, the memory 812 may store information received from the AMF 102 described above or received from an external entity. As another example, when the NF is the PCF 103, necessary control information or/and received information from the PCF 103 may be stored. In the case of other network entities, information necessary for the operation described above may be stored in the same manner.

In addition to the configuration described above, the NF may further include various interfaces for accessing an operator. In the present disclosure, no special restrictions are placed on these additional configurations.

9 is a block diagram of an internal function of a terminal according to various embodiments of the present disclosure.

Referring to FIG. 9, the terminal 100 may include a transmission/reception unit 910, a control unit 920, and a memory 930. The terminal 100 may additionally have more components depending on the implementation method. For example, various additional devices such as a display, an input unit, and a sensor for a user interface may be further included. In the present disclosure, no restrictions are placed on these additional configurations.

The transmission/reception unit 910 may be connected to the base station 101 through a wireless channel based on the respective embodiments described in FIGS. 1 to 7, and may transmit and receive signals and/or messages with the base station 101. I can. When the terminal 100 communicates with a 5G network, the transceiver 910 may be a device capable of transmitting/receiving with a 5G communication network. In addition, the transmission/reception unit 910 may include a communication processor as necessary. When the transmission/reception unit 910 does not include a communication processor, all signals and/or messages may be processed by the control unit.

The controller 920 may control the basic operation of the terminal 100, and may perform control of reception and storage of the messages described above. In addition, control for transmitting or receiving data through a specific network slice may be performed.

The memory 930 can store various data required for control of the terminal 100, and stores messages received from the base station 101 and/or a specific NF of the core network in order to communicate using the network slice described above. You can have an area for it.

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

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

These programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), and electrically erasable programmable 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 It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all of them. In addition, a plurality of configuration memories may be included.

In addition, the program is a communication network such as the Internet (Internet), Intranet (Intranet), LAN (local area network), WAN (wide area network), or SAN (storage area network), or a communication network composed of a combination thereof. It may be stored in an accessible storage device. Such a storage device may access a device performing an embodiment of the present disclosure through an external port. In addition, a separate storage device on the communication network may access a device performing an embodiment of the present disclosure.

In the above-described specific embodiments of the present disclosure, components included in the disclosure are expressed in the singular or plural according to the presented specific embodiments. However, the singular or plural expression is selected appropriately for the situation presented for convenience of description, and the present disclosure is not limited to the singular or plural constituent elements, and even constituent elements expressed in plural are composed of the singular or in the singular. Even the expressed constituent elements may be composed of pluralities.

Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, various modifications may be made without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure is limited to the described embodiments and should not be defined, and should be determined by the scope of the claims and equivalents as well as the scope of the claims to be described later.

100: terminal (UE) 101: base station (RAN)
102: AMF 103: PCF
203, 303: modem
205, 305: control unit
207, 307: memory
209: network interface
309: input
311: display

Claims (1)

In a method for controlling a data rate of a terminal in an access and mobility management function (AMF) device of a wireless communication system,
Receiving a registration request message including an identifier of the terminal from the terminal;
Transmitting a registration request message including the identifier of the terminal through Unified Data Management (UDM);
Receiving subscription information including network slice information that can be allocated to the terminal from the UDM;
Inquiring for policy association of the terminal including the network slice information to a Policy Control Function (PCF) device;
Receiving a policy association response message including total transmission rate limitation information of a serving network slice from the PCF; And
Providing the total transmission rate limit information of the serving network slice to the base station of the terminal; comprising, a data rate control method for the terminal performing communication through the network slice in the AMF device of the wireless communication system.

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