UE and SMF

Abstract

According to an aspect of the present application, a communication unit for implementing a function for ATSSS in a 5GS is provided. The UE of the present application transmits a PDU session establishment request message including a MA PDU request indication and an ATSSS capability, receives, in a case where establishment of a MA PDU session is allowed and in a case where establishment of user plane resources for only one of 3GPP access and non-3GPP (non-3GPP) access is allowed, a PDU session establishment accept message including ATSSS rules, information indicating that establishment of a MA PDU session is allowed, an access type corresponding to the user plane resources allowed to be established, a value indicating a reason for which establishment of user plane resources for an access type different from the access type is not allowed, and establishes a MA PDU session.

Description

Technical Field

[0001] This application relates to UE and SMF. This application claims priority to Japanese Patent Application No. 2019-111959, filed on June 17, 2019, and the entire contents of which are incorporated herein by reference. Background Technology

[0002] Within the 3GPP (3rd Generation Partnership Project), the system architecture of 5GS (5G System), a fifth-generation (5G) mobile communication system, was studied, and support for new processes and functions was discussed (see Non-Patent Literature 1 and Non-Patent Literature 2). Within 5GS (5G System), the 5GC (5G Core Network), as a new core network, was studied to provide a variety of services. Furthermore, discussions began on ATSSS (Access Traffic Steering, Switching and Splitting) for supporting communications requiring high reliability and / or low latency in 5GS (see Non-Patent Literature 1, Non-Patent Literature 2, and Non-Patent Literature 3).

[0003] Existing technical documents

[0004] Non-patent literature

[0005] Non-patent document 1: 3GPP TS 23.501V16.1.0 (2019-06); 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; SystemArchitecture for the 5G System; Stage 2 (Release 16)

[0006] Non-patent document 2: 3GPP TS 23.502V16.1.1(2019-06); 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Procedures for the 5G System; Stage 2 (Release 16)

[0007] Non-patent document 3: 3GPP TR 23.793V16.0.0 (2018-12); 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Study onaccess traffic steering, switch and splitting support in the 5G systemarchitecture (Release 16) Summary of the Invention

[0008] The problem the invention aims to solve

[0009] In the discussion of ATSSS, in addition to the usual PDU (Protocol Data Unit or Packet Data Unit) sessions (also known as single-access PDU sessions or SA PDU sessions), a communication method using a special type of PDU session called a multi-access PDU session (also known as an MA PDU session) was discussed. However, the details of the behavior of each device when a PDU session establishment procedure is performed to establish an MA PDU session have not been discussed. In particular, it is unclear what actions each device will take when the UE sends a PDU session establishment request message during the same process, and whether the network side allows or rejects the PDU session establishment request message.

[0010] The present invention was made in view of the circumstances described above, and its object is to provide a unit that clarifies the behavior of each device when performing a PDU session establishment process to establish an MA PDU session.

[0011] Technical solution

[0012] One embodiment of the present invention provides a UE (User Equipment) comprising a control unit and a transceiver unit. The control unit initiates a PDU session establishment process. When the transceiver unit receives a PDU session establishment acceptance message including an ATSSS (Access Traffic Steering, Switching, Splitting) container (IE) containing ATSSS rules, the control unit identifies whether an MA (Multi-Access) PDU session has already been established, and the user plane resources of the MA PDU session in the already established access.

[0013] Furthermore, an embodiment of the present invention provides an SMF (Session Management Function) comprising a control unit and a transceiver unit. The control unit executes a PDU session establishment process, and the transceiver unit sends a PDU session establishment acceptance message including an ATSSS (Access Traffic Steering, Switching, Splitting) container IE (Information Element) containing ATSSS rules. Thus, the control unit indicates to the UE (User Equipment) that an MA (Multi-Access) PDU session has been established, and the status of user plane resources for the MA PDU session in the access of the established party.

[0014] According to one embodiment of the present invention, a UE (User Equipment) includes a control unit and a transceiver unit. The transceiver unit receives first information from an AMF (Access and Mobility Management Function) indicating whether the network supports ATSSS (Access Traffic Steering, Switching, Splitting). The control unit determines whether the network supports ATSSS based on the first information. If the network does not support ATSSS, the control unit does not initiate a PDU session establishment process to establish an MA (Multi-Access) PDU (Protocol Data Unit) session.

[0015] Beneficial effects

[0016] According to one aspect of the present invention, the functionality of ATSSS in 5GS can be used. Specifically, the behavior of each device can be determined when a MA PDU session is established by performing a PDU session establishment process. Attached Figure Description

[0017] Figure 1 This is a diagram illustrating a general outline of mobile communication system 1.

[0018] Figure 2 This is a diagram illustrating the detailed structure of mobile communication system 1.

[0019] Figure 3 This is a diagram illustrating the device configuration of the UE.

[0020] Figure 4 This diagram mainly illustrates the configuration of the access network device.

[0021] Figure 5 This diagram mainly illustrates the composition of the core network device.

[0022] Figure 6 This is a diagram illustrating the PDU session establishment process. Detailed Implementation

[0023] Hereinafter, after describing the mobile communication system, the configuration of each device, and the terms, identification information, and processes used in the embodiments, which have many common parts in the various embodiments, the embodiments for carrying out the present invention will be described.

[0024] [1. Overview of Mobile Communication Systems]

[0025] Here, we will explain the mobile communication system.

[0026] first, Figure 1 This is a diagram used to illustrate a general outline of mobile communication system 1. Figure 2 This is a diagram used to illustrate the detailed configuration of the mobile communication system 1.

[0027] exist Figure 1 The document describes the mobile communication system 1 as consisting of UE (User Equipment)_10, access network_100, access network_102, core network_200, and DN (Data Network)_300. It should be noted that sometimes the reference numerals for these devices and networks are omitted in the accompanying drawings, such as UE, access network, core network, and DN.

[0028] In addition, Figure 2The document describes the device / network functions of UE_10, base station device_110, base station device_120, AMF (Access and Mobility Management Function)_210, SMF (Session Management Function)_220, UPF (User Plane Function)_230, N3IWF (Non-3GPP InterWorking Function)_240, PCF (Policy Control Function)_250, and DN_300, as well as the interfaces connecting these devices and network functions to each other. It should be noted that sometimes the reference numerals for these devices and network functions are omitted in the accompanying drawings, such as UE, base station device, AMF, SMF, UPF, N3IWF, PCF, and DN.

[0029] It should be noted that the 5GS (5G System) of a 5G system consists of a UE, an access network, and a core network, but may further include a DN.

[0030] A UE is a device capable of connecting to network services via 3GPP access (also known as 3GPP access network, 3GPP AN) and / or non-3GPP access (also known as non-3GPP access network, non-3GPP AN)). A UE can be a mobile phone, smartphone, or other terminal device capable of wireless communication, or a terminal device capable of connecting to EPS (Evolved Packet System) and 5GS as 4G systems. A UE can possess UICC (Universal Integrated Circuit Card) or eUICC (Embedded UICC). It should be noted that a UE can function as either a user equipment or a terminal device. Furthermore, a UE is a device capable of utilizing ATSSS (Access Traffic Steering, Switching, and Splitting) functionality, i.e., an ATSSS-capable UE.

[0031] Furthermore, the access network can also be called the 5G access network (5G AN). The 5G AN consists of NG-RAN (NG Radio Access Network) and / or non-3GPP access network (non-3GPP AN). One or more base station devices are configured in the NG-RAN. This base station device can be a gNB. A gNB is a node that provides the NR (New Radio) user plane and control plane to the UE, and is a node connected to the 5GC via an NG interface (including the N2 or N3 interface). That is, a gNB is a base station device newly designed for 5GS, with different functions than the base station device (eNB) used in EPS. Furthermore, in the case of multiple gNBs, each gNB is interconnected, for example, via an Xn interface. It should be noted that base station device_110 corresponds to a gNB.

[0032] Furthermore, NG-RAN will be referred to as 3GPP access below. Additionally, the wireless LAN access network and non-3GPP AN will be referred to as non-3GPP access. Furthermore, nodes configured in the access network will be collectively referred to as NG-RAN nodes.

[0033] In addition, the devices included in the access network and / or the devices included in the access network are sometimes referred to as access network devices.

[0034] It should be noted that Access Network_100 corresponds to 3GPP access, while Access Network_102 corresponds to non-3GPP access.

[0035] In addition, a base station device 110 is configured in access network 100, and a base station device 120 is configured in access network 102. It should be noted that base station devices 110 and 120 may also utilize the ATSSS function.

[0036] In addition, Access Network _102 is sometimes also referred to as Untrusted Non-3GPP Access or Trusted Non-3GPP Access. Figure 2The base station apparatus 120 and N3IWF are described for the case of untrusted non-3GPP access. That is, base station apparatus 120 and N3IWF are used when access network _102 is an untrusted non-3GPP access. Furthermore, when access network _102 is a trusted non-3GPP access (also known as Trusted Non-3GPP Access Network, TNAN), a Trusted Non-3GPP Access Point (also known as TNAP) and a Trusted Non-3GPP Gateway Function (also known as TNGF) are used instead of base station apparatus 120 and N3IWF. TNAP and TNGF are configured in access network _102 or core network _200.

[0037] Furthermore, the core network corresponds to 5GC (5G Core Network). 5GC includes, for example, AMF, UPF, SMF, and PCF. Here, 5GC can also be represented as 5GCN (5G Core Network). It should be noted that AMF, UPF, SMF, and PCF can also utilize ATSSS functionality.

[0038] In addition, N3IWF is configured in access network_102 or core network_200.

[0039] In addition, the core network and / or the devices included in the core network are sometimes referred to as core network devices.

[0040] The core network can be an IP mobile communication network operated by a Mobile Network Operator (MNO) that connects the access network and the DN; it can also be the core network used by a mobile communication operator that operates and manages the mobile communication system 1; or it can be the core network used by virtual mobile communication operators and virtual mobile communication service providers such as MVNO (Mobile Virtual Network Operator) and MVNE (Mobile Virtual Network Enabler).

[0041] Furthermore, a DN can also be a DN that provides communication services to the UE. A DN can be configured as a packet data service network, or it can be configured for each service. Moreover, a DN can include connected communication terminals. Therefore, connecting to a DN can be connecting to a communication terminal or server device configured on the DN. Furthermore, sending and receiving user data with a DN can be sending and receiving user data with a communication terminal or server device configured on the DN.

[0042] Furthermore, hereinafter, at least a portion of the access network, core network, DN, and / or more than one of the devices included therein may be referred to as a network or network device. That is to say, the sending and receiving of messages and / or the execution of processes by a network and / or a network device means that at least a portion of the access network, core network, DN, and / or more than one of the devices included therein are sending and receiving messages and / or executing processes.

[0043] Furthermore, the UE can connect to the access network. Additionally, the UE can connect to the core network via the access network. Moreover, the UE can connect to the DN via both the access network and the core network. That is, the UE can send and receive user data with the DN. When sending and receiving user data, it can use not only IP (Internet Protocol) communication but also non-IP communication.

[0044] Here, IP communication refers to data communication using IP, which involves sending and receiving data via IP packets. An IP packet consists of an IP header and a payload. The payload may include data transmitted and received by the devices and functions included in the EPS and the devices and functions included in the 5GS.

[0045] Furthermore, non-IP communication refers to data communication that does not use IP, but rather transmits and receives data through a structure different from IP packets. For example, non-IP communication can be achieved by transmitting and receiving application data without IP headers, or it can transmit and receive user data sent and received by the UE using other headers such as MAC headers and Ethernet (registered trademark) frame headers.

[0046] [2. Composition of each device]

[0047] Next, the configuration of the various devices (UE and / or access network device and / or core network device) used in each embodiment will be described using the accompanying drawings. It should be noted that each device can be configured as physical hardware, as logical (virtual) hardware built on general-purpose hardware, or as software. Furthermore, at least some (including all) of the functions possessed by each device can also be configured as physical hardware, logical hardware, or software.

[0048] It should be noted that the storage units (storage unit_330, storage unit_440, storage unit_540) within the various devices and functions mentioned below are, for example, composed of semiconductor memory, SSD (Solid State Drive), HDD (Hard Disk Drive), etc. Furthermore, each storage unit can store not only the information originally set at the factory, but also various information exchanged between the device itself and other devices and functions (e.g., UE and / or access network devices and / or core network devices and / or PDN and / or DN). In addition, each storage unit can store identification information, control information, flags, parameters, etc., included in the control messages exchanged during the various communication processes described later. Furthermore, each storage unit can store this information in each UE.

[0049] [2.1. Device Configuration of UE_10]

[0050] First, use Figure 3 Examples of device configurations for the UE used in each embodiment will be described. The UE comprises a control unit_300, an antenna_310, a transceiver unit_320, and a storage unit_330. The control unit_300, transceiver unit_320, and storage unit_330 are connected via a bus. The transceiver unit_320 is connected to the antenna_310.

[0051] The control unit 300 is a functional unit that controls the overall operation and functions of the UE. It should be noted that the control unit 300 can also handle functions not possessed by other functional units in the UE (transceiver unit 320, storage unit 330). The control unit 300 implements various processes within the UE by reading and executing various programs stored in the storage unit 330 as needed.

[0052] The transceiver unit 320 is a functional unit used for wireless communication with base station devices and the like within the access network via the antenna 310. That is, the UE can use the transceiver unit 320 to send and receive user data and / or control information between the access network device and / or core network device and / or DN.

[0053] Specifically, the UE can communicate with base station device 110, base station device 120, and TNAP using transceiver unit 320. That is, the UE communicates with base station device 110 when communicating via 3GPP access. Furthermore, the UE communicates with base station device 120 or TNAP when communicating via non-3GPP access. More specifically, the UE communicates with base station device 120 when communicating via untrusted non-3GPP access, and communicates with TNAP when communicating via trusted non-3GPP access. Thus, the UE can change its connection destination depending on the access network used.

[0054] In addition, the UE can communicate with core network devices (AMF, SMF, UPF, etc.) by using the transceiver unit _320.

[0055] The UE can send and receive NAS (Non-Access-Stratum) messages with the AMF via the N1 interface (the interface between the UE and the AMF). However, the N1 interface is a logical interface; therefore, actual communication between the UE and the AMF is conducted via base station device_110, base station device_120, and TNAP. Specifically, when communicating via 3GPP access, the UE can communicate with the AMF via base station device_110. Furthermore, when communicating via untrusted non-3GPP access, the UE can communicate with the AMF via base station device_120 and N3IWF. Additionally, when communicating via trusted non-3GPP access, the UE can communicate with the AMF via TNAP and TNGF. The information exchanged between the UE and the AMF is primarily control information.

[0056] Furthermore, the UE can communicate with the SMF using the N1 and N11 interfaces (the interface between the AMF and SMF). Specifically, the UE can communicate with the SMF via the AMF. It should be noted that, as mentioned above, the communication path between the UE and the AMF can sometimes follow three paths depending on the access method (3GPP access, Untrusted Non-3GPP Access, Trusted Non-3GPP Access). The information exchanged between the UE and the SMF is mainly control information.

[0057] Furthermore, the UE can communicate with the UPF using the N3 interface (the interface between the access network and the UPF). Specifically, the UE can communicate with the UPF via base station device_110 when communicating via 3GPP access. Additionally, the UE can communicate with the UPF via base station device_120 and N3IWF when communicating via untrusted non-3GPP access. Furthermore, the UE can communicate with the UPF via TNAP and TNGF when communicating via trusted non-3GPP access. The communication path between the UE and the UPF is primarily used for transmitting and receiving user data.

[0058] In addition, the UE can communicate with the PCF using the N1 interface, N11 interface, and N7 interface (the interface between the SMF and PCF). Specifically, the UE can communicate with the PCF via the AMF and SMF. It should be noted that, as mentioned above, the communication path between the UE and the AMF can sometimes follow three paths depending on the access method (3GPP access, Untrusted Non-3GPP Access, Trusted Non-3GPP Access). The information exchanged between the UE and the PCF is mainly control information.

[0059] Furthermore, the UE can communicate with the DN using the N3 and N6 interfaces (the interface between the UPF and the DN). Specifically, when communicating via 3GPP access, the UE can communicate with the DN via base station device_110 and the UPF. Additionally, when communicating via untrusted non-3GPP access, the UE can communicate with the DN via base station device_120, N3IWF, and the UPF. Furthermore, when communicating via trusted non-3GPP access, the UE can communicate with the DN via TNAP, TNGF, and the UPF. The communication path between the UE and the DN, i.e., the PDU session or MA PDU session, is primarily used for sending and receiving user data.

[0060] It should be noted that the above only describes the communication between the UE and the representative devices / functions in this specification. Of course, the UE can also communicate with other devices / functions, that is, core network devices other than those mentioned above.

[0061] Storage unit 330 is a functional unit used to store programs, user data, control information, etc. required for various actions of the UE.

[0062] Furthermore, the UE is a UE that supports ATSSS functionality, and ideally, the control information received from the core network side is stored in the storage unit 330. Moreover, the control unit 300 may have the following functions: determining whether to perform communication using an MA PDU session or an SA PDU session based on the control information received from the core network side or the control information stored in the storage unit 330. Furthermore, when communicating using an MA PDU session, it can determine whether communication is conducted solely via 3GPP access, solely via non-3GPP access, or both. Similarly, when communicating using an SA PDU session, it can determine whether communication is conducted solely via 3GPP access or solely via non-3GPP access. Based on these determinations, the control unit 300 controls the transceiver unit 320 to enable it to perform communication appropriately.

[0063] In addition, the UE can also have the following function: when communicating using an MA PDU session, determine which access point should be routed to for uplink services based on the ATSSS rules received from the SMF.

[0064] In addition, the UE may also have the function of requesting the establishment of an MA PDU session based on URSP rules received from the PCF.

[0065] [2.2. Base Station Device_110 Device Configuration]

[0066] Next, use Figure 4 Examples of the configuration of the base station device_110 used in each embodiment will be described. The base station device_110 is a base station device configured for 3GPP access. The base station device_110 consists of a control unit_400, an antenna_410, a network connection unit_420, a transceiver unit_430, and a storage unit_440. The control unit_400, network connection unit_420, transceiver unit_430, and storage unit_440 are connected via a bus. The transceiver unit_430 is connected to the antenna_410. Furthermore, the base station device_110 may also be a base station device supporting ATSSS functionality.

[0067] The control unit 400 is a functional unit that controls the overall operation and functions of the base station device 110. It should be noted that the control unit 400 can also handle functions not possessed by other functional units in the base station device 110 (network connection unit 420, transceiver unit 430, and storage unit 440). The control unit 400 implements various processes within the base station device 110 by reading and executing various programs stored in the storage unit 440 as needed.

[0068] The network connection unit 420 is a functional unit for enabling communication between the base station device 110 and the AMF and / or UPF. That is, the base station device 110 can use the network connection unit 420 to send and receive control information and / or user data with the AMF and / or UPF, etc.

[0069] Specifically, the base station device_110 can communicate with the AMF via the N2 interface (the interface between the access network and the AMF) using the network connection unit_420. Furthermore, the base station device_110 can communicate with the UPF via the N3 interface using the network connection unit_420.

[0070] The transceiver unit 430 is a functional unit used for wireless communication with the UE via the antenna 410. That is, the base station device 110 can use the transceiver unit 430 and the antenna 410 to send and receive user data and / or control information with the UE.

[0071] Furthermore, the base station device_110 has the following function: upon receiving user data and / or control information destined for the core network device from the UE, it transmits the user data and / or control information to the core network device.

[0072] It should be noted that the above only describes the communication between the base station device_110 and representative devices / functions. Of course, the base station device_110 can also communicate with other devices / functions mentioned above, that is, core network devices other than those mentioned above.

[0073] The storage unit 440 is a functional unit used to store programs, user data, control information, etc. required for various operations of the base station device 110.

[0074] [2.3. Configuration of Base Station Device_120]

[0075] Next, use Figure 4 Example configurations of the base station device_120 used in each embodiment will be described. The base station device_120 is a base station device configured for untrusted non-3GPP access. The base station device_120 consists of a control unit_400, an antenna_410, a network connection unit_420, a transceiver unit_430, and a storage unit_440. The control unit_400, network connection unit_420, transceiver unit_430, and storage unit_440 are connected via a bus. The transceiver unit_430 is connected to the antenna_410. Furthermore, the base station device_120 may also be a base station device supporting ATSSS functionality.

[0076] The control unit 400 is a functional unit that controls the overall operation and functions of the base station device 120. It should be noted that the control unit 400 can also handle functions not possessed by other functional units in the base station device 120 (network connection unit 420, transceiver unit 430, and storage unit 440). The control unit 400 implements various processes within the base station device 120 by reading and executing various programs stored in the storage unit 440 as needed.

[0077] The network connection unit 420 is a functional unit for enabling communication between the base station device 120 and the N3IWF, and specifically for communication with the AMF and / or UPF via the N3IWF. That is, the base station device 120 can use the network connection unit 420 to send and receive control information and / or user data with the N3IWF. Furthermore, the base station device 120 can use the network connection unit 420 to send and receive control information and / or user data with the AMF and / or UPF, etc.

[0078] In other words, the base station device_120 can communicate with the N3IWF via the Y2 interface (the interface between the access network and the N3IWF) using the network connection unit_420. Furthermore, the base station device_120 can communicate with the AMF via the N3IWF and the N2 interface (the interface between the N3IWF and the AMF). Additionally, the base station device_120 can communicate with the UPF via the N3 interface (the interface between the N3IWF and the UPF).

[0079] The transceiver unit 430 is a functional unit used for wireless communication with the UE via the antenna 410. That is, the base station device 120 can use the transceiver unit 430 and the antenna 410 to send and receive user data and / or control information with the UE via the Y1 interface (the interface between the access network and the UE).

[0080] Furthermore, the base station device_120 has the following function: upon receiving user data and / or control information destined for the core network device from the UE, it transmits the user data and / or control information to the core network device.

[0081] It should be noted that the above only describes the communication between the base station device_120 and representative devices / functions. Of course, the base station device_120 can also communicate with other devices / functions mentioned above, that is, other core network devices mentioned above.

[0082] The storage unit 440 is a functional unit used to store programs, user data, control information, etc. required for the various operations of the base station device 120.

[0083] [2.4. TNAP Device Configuration]

[0084] Next, use Figure 4 Examples of device configurations for the TNAP used in each embodiment will be described. A TNAP is a base station device (also called an access point) configured in non-3GPP access. The TNAP consists of a control unit_400, an antenna_410, a network connection unit_420, a transceiver unit_430, and a storage unit_440. The control unit_400, network connection unit_420, transceiver unit_430, and storage unit_440 are connected via a bus. The transceiver unit_430 is connected to the antenna_410. Furthermore, the TNAP may also be a TNAP supporting ATSSS functionality.

[0085] The control unit 400 is a functional unit that controls the overall operation and functions of the TNAP. It should be noted that the control unit 400 can also handle functions not possessed by other functional units in the TNAP (network connection unit 420, transceiver unit 430, and storage unit 440). The control unit 400 implements various processes within the TNAP by reading and executing various programs stored in the storage unit 440 as needed.

[0086] The network connection unit 420 is a functional unit for communication between the TNAP and the TNGF, and specifically for communication with the AMF and / or UPF via the TNGF. That is, the TNAP can use the network connection unit 420 to send and receive control information and / or user data with the TNGF. Furthermore, the TNAP can use the network connection unit 420 to send and receive control information and / or user data with the AMF and / or UPF, etc.

[0087] In other words, TNAP can communicate with TNGF via the Ta interface (the interface between TNAP and TNGF) using the network connection unit _420. Furthermore, TNAP can communicate with AMF via TNGF and the N2 interface (the interface between TNGF and AMF). Additionally, TNAP can communicate with UPF via TNGF and the N3 interface (the interface between TNGF and UPF).

[0088] The transceiver unit 430 is a functional unit used for wireless communication with the UE via the antenna 410. That is, the TNAP can use the transceiver unit 430 and the antenna 410 to send and receive user data and / or control information with the UE via the Yt interface (the interface between the TNAP and the UE).

[0089] In addition, TNAP has the following function: upon receiving user data and / or control information destined for a core network device from the UE, it transmits the user data and / or control information to that core network device.

[0090] It should be noted that the above only describes the communication between TNAP and representative devices / functions. TNAP can of course also communicate with other devices / functions mentioned above, that is, core network devices other than those mentioned above.

[0091] Storage unit 440 is a functional unit used to store programs, user data, control information, etc. required for various operations of TNAP.

[0092] [2.5. Device Configuration of N3IWF_240]

[0093] Next, use Figure 5 Examples of device / functional configurations of the N3IWF used in each embodiment will be described. The N3IWF is a device and / or function configured between the non-3GPP access network and the 5GS when the UE connects to the 5GS via untrusted non-3GPP access. Specifically, the N3IWF is configured in the untrusted non-3GPP access network or the core network. The N3IWF consists of a control unit_500, a network connection unit_520, and a storage unit_540. The control unit_500, network connection unit_520, and storage unit_540 are connected via a bus. Furthermore, the N3IWF can also be an N3IWF supporting ATSSS functionality.

[0094] The control unit 500 is a functional unit that controls the overall operation and functions of the N3IWF. It should be noted that the control unit 500 can also handle functions not possessed by other functional units in the N3IWF (network connection unit 520, storage unit 540). The control unit 500 implements various processes within the N3IWF by reading and executing various programs stored in the storage unit 540 as needed.

[0095] The network connection unit 520 is a functional unit for enabling communication between the N3IWF and the base station device 120 and / or the AMF and / or the UPF. Specifically, the N3IWF can use the network connection unit 520 to send and receive control information and / or user data with the base station device 120. Furthermore, the N3IWF can use the network connection unit 520 to send and receive control information and / or user data with the AMF and / or UPF, etc.

[0096] In other words, the N3IWF can communicate with the base station device 120 via the Y2 interface using the network connection unit 520. Furthermore, the N3IWF can communicate with the AMF via the N2 interface. Additionally, the N3IWF can communicate with the UPF via the N3 interface.

[0097] It should be noted that the above only describes the communication between N3IWF and representative devices / functions. Of course, N3IWF can also communicate with other devices / functions mentioned above, that is, core network devices other than those mentioned above.

[0098] The storage unit 540 is a functional unit used to store programs, user data, control information, etc. required for various operations of the N3IWF.

[0099] It should be noted that the N3IWF has the following functions: establishing IPsec tunnels with the UE; terminating the N2 interface for the control plane; terminating the N3 interface for the user plane; relaying NAS signaling between the UE and the AMF; processing N2 signaling from the SMF for PDU sessions and QoS; establishing IPsec SA (Security Association) to support services for PDU sessions; relaying user plane packets between the UE and the UPF (including encapsulation / decapsulation of packets for IPsec and N3 tunnels); serving as a local mobile anchor point in an untrusted non-3GPP access network; and selecting the AMF. All these functions are controlled by the control unit _500.

[0100] [2.6. TNGF Device Configuration]

[0101] Next, use Figure 5 Examples of device / functional configurations of the TNGF used in each embodiment will be described. The TNGF is a device and / or function configured between the non-3GPP access and the 5GC when the UE connects to the 5GS via a non-3GPP access network. Specifically, the TNGF is configured in the non-3GPP access network or the core network. The TNGF consists of a control unit_500, a network connection unit_520, and a storage unit_540. The control unit_500, network connection unit_520, and storage unit_540 are connected via a bus. Furthermore, the TNGF can also be a TNGF that supports ATSSS functionality.

[0102] The control unit 500 is a functional unit that controls the overall operation and functions of the TNGF. It should be noted that the control unit 500 can also handle functions not possessed by other functional units within the TNGF (network connection unit 520, storage unit 540). The control unit 500 implements various processes within the TNGF by reading and executing various programs stored in the storage unit 540 as needed.

[0103] The network connection unit 520 is a functional unit for enabling communication between the TNGF and the TNAP and / or the AMF and / or the UPF. Specifically, the TNGF can use the network connection unit 520 to send and receive control information and / or user data with the TNAP. Furthermore, the TNGF can use the network connection unit 520 to send and receive control information and / or user data with the AMF and / or the UPF, etc.

[0104] In other words, TNGF can communicate with TNAP via the Y2 interface using the network connection unit _520. Furthermore, TNGF can communicate with AMF via the N2 interface. Additionally, TNGF can communicate with UPF via the N3 interface.

[0105] It should be noted that the above only describes the communication between TNGF and representative devices / functions. Of course, TNGF can also communicate with other devices / functions mentioned above, that is, core network devices other than those mentioned above.

[0106] Storage unit 540 is a functional unit used to store programs, user data, control information, etc. required for various operations of TNGF.

[0107] It should be noted that the TNGF has the following functions: terminating the N2 and N3 interfaces; acting as an authorizer when the UE logs into the 5GC via the TNAN; selecting the AMF; transparently (without processing) relaying NAS messages between the UE and the AMF; processing SMF and N2 signaling to support PDU sessions; QoS functions; transparently (without processing) relaying PDUs between the UE and the UPF; and acting as a local security anchor within the TNAN. All these functions are controlled by the control unit _500.

[0108] [2.7. AMF_210 Device Configuration]

[0109] Next, use Figure 5 Examples of the device configuration of the AMF used in each embodiment will be described. The AMF consists of a control unit_500, a network connection unit_520, and a storage unit_540. The control unit_500, the network connection unit_520, and the storage unit_540 are connected via a bus. The AMF can be a node that processes the control plane. In addition, the AMF can also be an AMF that supports ATSSS functionality.

[0110] The control unit 500 is a functional unit that controls the overall operation and functions of the AMF. It should be noted that the control unit 500 can also handle functions that other functional units in the AMF (network connection unit 520, storage unit 540) do not possess. The control unit 500 implements various processes within the AMF by reading and executing various programs stored in the storage unit 540 as needed.

[0111] The network connection unit 520 is a functional unit for enabling the AMF to connect with base station devices and / or SMF and / or PCF and / or UDM and / or SCEF within the 5G AN. That is, the AMF can use the network connection unit 520 to send and receive user data and / or control information with base station devices and / or SMF and / or PCF and / or UDM and / or SCEF within the 5G AN.

[0112] Reference Figure 2 In detail, the AMF within the 5GC can communicate with the base station via the N2 interface using the network connection unit_520, communicate with the UDM via the N8 interface (the interface between the AMF and UDM), communicate with the SMF via the N11 interface, and communicate with the PCF via the N15 interface (the interface between the AMF and PCF). Furthermore, the AMF can send and receive NAS messages with the UE via the N1 interface using the network connection unit_520. However, the N1 interface is a logical interface; therefore, communication between the UE and AMF is actually conducted via the 5G AN.

[0113] Storage unit 540 is a functional unit used to store programs, user data, control information, etc. required for various operations of AMF.

[0114] It should be noted that the AMF has the following functions: exchanging control messages with the RAN using the N2 interface; exchanging NAS messages with the UE using the N1 interface; encrypting and protecting the integrity of NAS messages; performing registration management (RM) functions; connection management (CM) functions; reachability management functions; mobility management functions for UEs, etc.; transmitting SM (Session Management) messages between the UE and the SMF; access authentication (access authorization) functions; security anchor function (SEA); security context management (SCM); supporting the N2 interface for the N3IWF (Non-3GPP Interworking Function); supporting the transmission and reception of NAS signals with the UE via the N3IWF; and authenticating UEs connected via the N3IWF. All these functions are controlled by the control unit _500.

[0115] Furthermore, the RM state of each UE is managed within the login management system. The RM state can be synchronized between the UE and the AMF (Application Management Frame). There are two RM states: a non-login state (RM-DEREGISTERED state) and a login state (RM-REGISTERED state). In the non-login state, the UE is not logged into the network; therefore, the UE context in the AMF does not have valid location and routing information for that UE, so the AMF is in a state where the UE cannot be reached. Conversely, in the login state, the UE is logged into the network; therefore, the UE can receive services that require network login. It should be noted that the RM state can also be represented as a 5GMM state. In this case, the non-login state can also be represented as a 5GMM-DEREGISTERED state, and the login state can also be represented as a 5GMM-REGISTERED state.

[0116] In other words, the 5GMM-REGISTERED state can be either the state where each device has established a 5GMM context or the state where a PDU session context has been established. It should be noted that when each device is in the 5GMM-REGISTERED state, UE_10 can begin sending and receiving user data and control messages, and can also respond to paging. Furthermore, it should be noted that when each device is in the 5GMM-REGISTERED state, UE_10 can execute login procedures and / or service request procedures other than the initial login procedure.

[0117] Furthermore, the 5GMM-DEREGISTERED state can be a state where each device has not established a 5GMM context, a state where the network does not know the location information of UE_10, or a state where the network cannot reach UE_10. It should be noted that when each device is in the 5GMM-DEREGISTERED state, UE_10 can start the login process or establish a 5GMM context by executing the login process.

[0118] Furthermore, the CM state of each UE is managed within the connection management system. The CM state can be synchronized between the UE and the AMF. There are two CM states: an IDLE state and a CONNECTED state. In the IDLE state, the UE is logged in but does not have a NAS signaling connection established with the AMF via the N1 interface. Additionally, in the IDLE state, the UE does not have an N2 connection or an N3 connection. On the other hand, in the CONNECTED state, the UE has a NAS signaling connection established with the AMF via the N1 interface. Furthermore, in the CONNECTED state, the UE can also have an N2 connection and / or an N3 connection.

[0119] Furthermore, connection management can be divided into CM states in 3GPP access and CM states in non-3GPP access. In this case, the CM states in 3GPP access can exist as both an IDLE state and a CONNECTED state. Similarly, the CM states in non-3GPP access can also exist as both an IDLE state and a CONNECTED state. It should be noted that the IDLE state can manifest as an idle mode, and the CONNECTED state can manifest as a connected mode.

[0120] It should be noted that the CM state can also manifest as 5GMM mode. In this case, the non-connected state can also manifest as 5GMM-IDLE mode, and the connected state can also manifest as 5GMM-CONNECTED mode. Furthermore, the non-connected state in 3GPP access can also manifest as 5GMM-IDLE mode over 3GPP access, and the connected state in 3GPP access can also manifest as 5GMM-CONNECTED mode over 3GPP access. Similarly, the non-connected state in non-3GPP access can also manifest as 5GMM-IDLE mode over non-3GPP access, and the connected state in non-3GPP access can also manifest as 5GMM-CONNECTED mode over non-3GPP access. It should be noted that 5GMM non-connected mode can be represented as idle mode, and 5GMM connected mode can be represented as connected mode.

[0121] Furthermore, an AMF can be configured more than once within the core network. Additionally, an AMF can be an NF that manages more than one NSI (Network Slice Instance). Furthermore, an AMF can also be a shared CP function (CCNF; Common CPNF, Control Plane Network Function) shared among multiple NSIs.

[0122] [2.8. SMF_220 Device Configuration]

[0123] Next, use Figure 5 Examples of the device configuration of the SMF used in each embodiment will be described. The SMF consists of a control unit_500, a network connection unit_520, and a storage unit_540. The control unit_500, the network connection unit_520, and the storage unit_540 are connected via a bus. The SMF can be a node that processes the control plane. In addition, the SMF can also be an SMF that supports ATSSS functionality.

[0124] The control unit 500 is a functional unit that controls the overall operation and functions of the SMF. It should be noted that the control unit 500 can also handle functions that other functional units in the SMF (network connection unit 520, storage unit 540) do not possess. The control unit 500 implements various processes within the SMF by reading and executing various programs stored in the storage unit 540 as needed.

[0125] The network connection unit_520 is a functional unit for enabling the SMF to connect with the AMF and / or UPF and / or PCF and / or UDM. That is, the SMF can use the network connection unit_B520 to send and receive user data and / or control information with the AMF and / or UPF and / or PCF and / or UDM.

[0126] Reference Figure 2 In detail, the SMF located in the 5GC can communicate with the AMF via the N11 interface through the network connection unit _520, communicate with the UPF via the N4 interface (the interface between the SMF and the UPF), communicate with the PCF via the N7 interface, and communicate with the UDM via the N10 interface (the interface between the SMF and the UDM).

[0127] Storage unit 540 is a functional unit used to store programs, user data, control information, etc. required for various operations of SMF.

[0128] It should be noted that the SMF has the following functions: session management functions such as establishing, modifying, and releasing PDU sessions; IP address allocation and management functions for the UE; UPF selection and control functions; UPF configuration functions for routing services to the appropriate destination (sending destination); SM portion functions for sending and receiving NAS messages; Downlink Data Notification functions; functions for providing AN-specific (per AN) SM information sent to the AN via the N2 interface through the AMF; functions for determining the SSC (Session and Service Continuity) mode for a session; and roaming functions. In addition, the SMF has the function of generating ATSSS rules and N4 rules based on PCC rules received from the PCF. ATSSS rules are used to control information about MA PDU sessions sent from the SMF to the UE. N4 rules are used to control information about MA PDU sessions sent from the SMF to the UPF. In addition, SMF has a function to manage PCC rules, ATSSS rules, and N4 rules in a corresponding manner (also known as mapping). All of these functions are controlled by the control unit _500.

[0129] [2.9. UPF_230 Device Configuration]

[0130] Next, use Figure 5 Examples of the device configuration of the UPF used in each embodiment will be described. The UPF consists of a control unit_500, a network connection unit_520, and a storage unit_540. The control unit_500, network connection unit_520, and storage unit_540 are connected via a bus. The UPF can be a node that processes the user plane. In addition, the UPF can also be a UPF that supports ATSSS functionality.

[0131] The control unit 500 is a functional unit that controls the overall operation and functions of the UPF. It should be noted that the control unit 500 can also handle functions that other functional units in the UPF (network connection unit 520, storage unit 540) do not possess. The control unit 500 implements various processes within the UPF by reading and executing various programs stored in the storage unit 540 as needed.

[0132] The network connection unit 520 is a functional unit for connecting the UPF to base station equipment and / or SMF and / or DN within the 5G AN. That is, the UPF can use the network connection unit 520 to send and receive user data and / or control information between itself and the base station equipment and / or SMF and / or DN within the 5G AN.

[0133] Reference Figure 2 In detail, the UPF within the 5GC can communicate with the base station device via the N3 interface through the network connection unit _520, communicate with the SMF via the N4 interface, communicate with the DN via the N6 interface, and communicate with other UPFs via the N9 interface (interface between UPFs).

[0134] Storage unit 540 is a functional unit used to store programs, user data, control information, etc. required for various operations of the UPF.

[0135] It should be noted that the UPF has the following functions: serving as an anchor point for intra-RAT mobility or inter-RAT mobility; acting as an external PDU session point for interconnection with the DN (i.e., acting as a gateway for transmitting user data between the DN and the core network); packet routing and transmission; UL CL (Uplink Classifier) ​​function for routing multiple service flows within a DN; branching point function for supporting multi-homed PDU sessions; QoS (Quality of Service) processing for the user plane; uplink service verification function; downlink packet buffering; and downlink data notification function. In addition, the UPF also has the following function: determining which access point should be routed to for downlink services when an MA PDU session is established based on N4 rules received from the SMF. All these functions are controlled by the control unit _500.

[0136] Furthermore, a UPF can be a gateway for IP and / or non-IP communication. Additionally, a UPF can be capable of transmitting IP communication or converting between non-IP and IP communication. Moreover, multiple configured gateways can connect the core network and a single DN. It should be noted that a UPF can have connectivity with other NFs and can also connect to various devices via other NFs.

[0137] It should be noted that the user plane is the user data transmitted and received between the UE and the network. The user plane can use PDU sessions for transmission and reception. Furthermore, in the 5GS scenario, the user plane can also be transmitted and received via the interface between the UE and the NG RAN and / or the N3 and / or N9 and / or N6 interfaces. The user plane can also be represented as a U-Plane.

[0138] Furthermore, the control plane is responsible for sending and receiving control messages for UE communication control. The control plane can use the NAS (Non-Access-Stratum) signaling connection between the UE and the AMF for sending and receiving. Moreover, in the case of 5GS, the control plane can also use the interface between the UE and the NG RAN and the N2 interface for sending and receiving. The control plane can also be represented as a Control Plane or a C-Plane.

[0139] Furthermore, the user plane (UP) can be a communication path for sending and receiving user data, and can consist of multiple bearers. Similarly, the control plane (CP) can be a communication path for sending and receiving control messages, and can also consist of multiple bearers. [2.10. Device Configuration of PCF_250]

[0140] Next, use Figure 5 Examples of the device configuration of the PCF used in each embodiment will be described. The PCF consists of a control unit_500, a network connection unit_520, and a storage unit_540. The control unit_500, the network connection unit_520, and the storage unit_540 are connected via a bus. Furthermore, the PCF may also be a PCF that supports ATSSS functionality.

[0141] The control unit 500 is a functional unit that controls the overall operation and functions of the PCF. It should be noted that the control unit 500 can also handle functions not possessed by other functional units in the PCF (network connection unit 520, storage unit 540). The control unit 500 implements various processes within the PCF by reading and executing various programs stored in the storage unit 540 as needed.

[0142] The network connection unit 520 is a functional unit used to connect the PCF to the SMF and / or AF (Application Function). That is, the PCF can use the network connection unit 520 to send and receive control information with the SMF and / or AF.

[0143] The PCF can communicate with the SMF via the N7 interface using the network connection unit_520. Furthermore, the PCF can communicate with the AF (Application Function) via the N5 interface (the interface between the PCF and the AF) using the network connection unit_520.

[0144] Storage unit 540 is a functional unit used to store programs, user data, control information, etc. required for various operations of the UPF.

[0145] It should be noted that the PCF has the following functions: supporting a unified policy framework, providing policy rules for control plane functions to enforce these, and accessing subscription information. In addition, the PCF also has the function of generating policies (also known as PCC rules) for MA PDU sessions, policies for SA PDU sessions, and URSP rules. These are sent to the SMF, and at least some of them are sometimes sent to the UE and sometimes to the UPF. All these functions are controlled by the control unit _500. [3. Explanation of highly technical terms and identification information used in various embodiments]

[0146] Next, the highly technical terms and identification information used in each implementation method will be explained in advance.

[0147] [3.1. Explanation of technical terms used in each embodiment]

[0148] First, the highly technical terms used in each implementation method will be explained.

[0149] A network refers to at least a portion of an access network, core network, and DN. Alternatively, it can refer to one or more devices included in at least a portion of an access network, core network, and DN as a network or network device. That is, the network performing message transmission, reception, and / or processing can mean that devices within the network (network devices and / or control devices) perform message transmission, reception, and / or processing. Conversely, the devices within the network performing message transmission, reception, and / or processing can mean that the network itself performs message transmission, reception, and / or processing.

[0150] Furthermore, SM (Session Management) messages (also known as NAS (Non-Access-Stratum) SM messages) can be NAS messages used during SM operations, or control messages exchanged between the UE and SMF via the AMF. Moreover, SM messages can include PDU session establishment request messages, PDU session establishment acceptance messages, PDU session completion messages, PDU session rejection messages, PDU session change request messages, PDU session change acceptance messages, and PDU session change response messages. Additionally, the SM operation can include the PDU session establishment process.

[0151] Furthermore, 5GS (5G System) service can be a connectivity service provided by the core network. Moreover, 5GS service can be a different service from EPS service, or it can be the same service as EPS service.

[0152] In addition, non-5GS services can be services other than 5GS services, and can also include EPS services and / or non-EPS services.

[0153] Furthermore, the DNN (Data Network Name) can be identification information for identifying the core network and / or external networks such as DN. Moreover, the DNN can also be used as information for selecting gateways such as UPFs that connect to the core network. The DNN can be considered equivalent to the APN (Access Point Name) in EPS.

[0154] Furthermore, a PDU session can be defined as the association between the DN providing PDU connectivity service and the UE, but more specifically, it can also be a connectivity established between the UE and an external gateway or DN. The UE can use the PDU session to send and receive user data with the DN by establishing a PDU session via the access network and core network in the 5GS. Here, the external gateway can refer to UPF, SCEF, etc. The UE can use the PDU session to perform the sending and receiving of user data with devices such as application servers configured on the DN. In addition, PDU connectivity service refers to the service that provides PDU exchange between the UE and the DN. Furthermore, this PDU session consists only of user plane resources in one access network (3GPP access network or non-3GPP access network), sometimes also called an SA PDU session. That is, an SA PDU session differs from an MA PDU session; it can be a PDU session that does not simultaneously consist of user plane resources in a 3GPP access network and user plane resources in a non-3GPP access network.

[0155] It should be noted that each device (UE and / or access network device and / or core network device) can manage the establishment of more than one identification information corresponding to a PDU session. This identification information can include one or more of the following: DNN, TFT, PDU session type, application identification information, NSI identification information, access network identification information, and SSC mode, and may further include other information. Furthermore, when multiple PDU sessions are established, the identification information corresponding to each PDU session can be the same or different.

[0156] Furthermore, an MA PDU session can also be a PDU session that provides PDU connectivity services that can simultaneously use one 3GPP access network and one non-3GPP access network. Additionally, an MA PDU session can also be a PDU session that provides PDU connectivity services that can use one 3GPP access network or one non-3GPP access network at a given point in time. In other words, an MA PDU session can consist solely of user plane resources in a 3GPP access network, or solely of user plane resources in a non-3GPP access network, and sometimes simultaneously of user plane resources in both 3GPP and non-3GPP access networks.

[0157] In other words, when a UE uses an MA PDU session to communicate with the DN, it can do so using only user plane resources in the 3GPP access network, only user plane resources in a non-3GPP access network, or a combination of both. Through these methods, the UE can use the MA PDU session to send and receive user data with devices such as application servers configured on the DN.

[0158] It should be noted that each device (UE and / or access network device and / or core network device) can manage the establishment of more than one identification information corresponding to the MA PDU session. This identification information can include one or more of the following: DNN, TFT, PDU session type, application identification information, NSI identification information, access network identification information, and SSC mode, and may further include other information. Furthermore, when establishing multiple MA PDU sessions, the identification information corresponding to each MA PDU session can be the same or different.

[0159] Furthermore, the PDU (Protocol Data Unit or Packet Data Unit) session type indicates the type of PDU session, which can be IPv4, IPv6, Ethernet (registered trademark), or Unstructured. Specifying IPv4 indicates that data transmission and reception will use IPv4. Specifying IPv6 indicates that data transmission and reception will use IPv6. Specifying Ethernet (registered trademark) indicates that Ethernet (registered trademark) frames will be transmitted and received. Additionally, Ethernet (registered trademark) can also indicate that communication will not use IP. Specifying Unstructured indicates that point-to-point (P2P) tunneling technology will be used to send and receive data to and from application servers, etc., located in the DN. For example, UDP / IP encapsulation technology can be used as a P2P tunneling technology. It should be noted that IP can be included among the above-mentioned other PDU session types. IP can be specified if the UE can use both IPv4 and IPv6. It should also be noted that IP can be represented as IPv4v6.

[0160] Furthermore, network slices (NS) refer to logical networks that provide specific network capabilities and characteristics. UEs and / or networks can support network slices (NW slices; NS) in 5GS.

[0161] Furthermore, a Network Slice Instance (NSI) refers to a network slice that is formed and configured by a collection of instances (entities) of Network Functions (NFs) and the required resources. Here, NF refers to a processing function in the network, adopted or defined in 3GPP. An NSI is an entity that constitutes more than one NS within the core network. Additionally, an NSI can be composed of virtual NFs (Network Functions) generated using an NST (Network Slice Template). Here, an NST is a logical expression of more than one NF associated with a resource request for providing the requested communication service or capability. That is, an NSI can be a collection within the core network composed of multiple NFs. Furthermore, an NSI can be a logical network configured to divide transmitted user data according to services, etc. An NS can contain more than one NF. NFs constituting an NS can be devices shared with other NSs or devices not shared with other NSs. A UE and / or devices within the network can be assigned to more than one NS based on login information such as NSSAI and / or S-NSSAI and / or UE usage type and / or more than one NSI ID and / or APN. It should be noted that the UE usage type is a parameter value included in the login information of the UE used to identify the NSI. The UE usage type can be stored in the HSS. The AMF can select the SMF and UPF based on the UE usage type.

[0162] Furthermore, S-NSSAI (Single Network Slice Selection Assistance information) is used to identify NSs. S-NSSAI can consist solely of SST (Slice / Service Type), or it can be composed of both SST and SD (Slice Differentiator). Here, SST refers to information indicating the expected actions of the NS in terms of function and service. SD can be information that interpolates the SST when selecting an NSI from multiple NSIs shown by the SST. S-NSSAI can be information specific to each PLMN, or it can be standard information common to all PLMNs. Additionally, the network can store more than one S-NSSAI in the UE's login information as the default S-NSSAI. It should be noted that when the S-NSSAI is the default S-NSSAI, the network can provide UE-related NSs even if the UE does not send a valid S-NSSAI to the network in the login request message.

[0163] Furthermore, NSSAI (Network Slice Selection Assistance Information) is a collection of S-NSSAIs. Each S-NSSAI included in the NSSAI is information for assisting the access network or core network in selecting the NSI. The UE can store NSSAIs allowed by the network on a per PLMN basis. In addition, NSSAIs can also be information used for selecting the AMF.

[0164] Furthermore, the SSC (Session and Service Continuity) mode represents the mode of session service continuity supported by the system and / or individual devices in a 5G system (5GS). More specifically, it can represent the type of session service continuity supported by the PDU session established between the UE and the UPF. It should be noted that the SSC mode can also represent the type of session service continuity set for each PDU session. Moreover, the SSC mode can consist of three modes: SSC mode 1, SSC mode 2, and SSC mode 3. It should also be noted that the SSC mode established for a PDU session may remain unchanged throughout the duration of the PDU session.

[0165] In addition, SSC mode 1 is the mode in which the network maintains connectivity services provided to the UE. It should be noted that, if a corresponding PDU session type of IPv4 or IPv6 has been established with the PDU session, the IP address can also be maintained while the session service continues.

[0166] Furthermore, regardless of the access technology used by the UE when connecting to the network, SSC mode 1 can be a session service continuity mode that continuously maintains the same UPF. More specifically, SSC mode 1 can be a mode that achieves session service continuity without changing the UPF used as the PDU session anchor for the established PDU session, even if the UE moves.

[0167] Furthermore, SSC mode 2 is a mode in which the network releases the connectivity services and corresponding PDU sessions provided to the UE. It should be noted that in SSC mode 2, even if a corresponding PDU session of IPv4, IPv6, or IPv4v6 has been established with the PDU session, the IP address assigned to the UE can be released when the anchor of the PDU session is changed.

[0168] Furthermore, SSC mode 2 can be a session service continuity mode that maintains the same UPF only within the service area of ​​the UPF. More specifically, SSC mode 2 can be a mode that achieves session service continuity without changing the UPF used by the established PDU session as long as the UE is within the service area of ​​the UPF. Moreover, if the UE moves, for example, leaves the service area of ​​the UPF, SSC mode 2 can also be a mode that changes the UPF used by the established PDU session to achieve session service continuity.

[0169] Here, the service area of ​​a UPF can be an area where a UPF can provide session service continuity, or it can be a subset of the access network such as a RAT or cell used by the UE when connecting to the network. Moreover, a subset of the access network can refer to a network consisting of one or more RATs and / or cells.

[0170] It should be noted that the anchor point (hereinafter referred to as the PDU session anchor) of the SSC mode 2 PDU session can be changed by each device executing the SSC mode 2 PDU session anchor point change process. It should also be noted that the anchor or anchor point can also be represented as an endpoint.

[0171] Furthermore, SSC mode 3 ensures network connectivity is not lost and allows the UE to be aware of changes to the user plane. It should be noted that in SSC mode 3, a new PDU session anchor can be established before terminating the existing PDU session, resulting in better connectivity. Moreover, in SSC mode 3, if the corresponding PDU session type is IPv4, IPv6, or IPv4v6, the IP address assigned to the UE may not be maintained when the PDU session anchor is changed.

[0172] Furthermore, SSC mode 3 can also be a session service continuity mode that allows the establishment of new PDU sessions and / or communication paths via new UPFs for the same DN before disconnecting the PDU session and / or communication path established between the UE and the UPF. Moreover, SSC mode 3 can also be a mode that allows the UE to be multi-homed for session service continuity. Furthermore, SSC mode 3 can also be a mode that allows the use of multiple PDU sessions and / or session service continuity with corresponding UPFs established for the PDU sessions. In other words, in SSC mode 3, each device can use multiple PDU sessions to achieve session service continuity, or it can use multiple UPFs to achieve session service continuity.

[0173] Here, when new PDU sessions and / or communication paths are established by various devices, the selection of a new UPF can be implemented by the network, and the new UPF can be the UPF most suitable for the UE to connect to the network. Moreover, when multiple PDU sessions and / or the UPFs used by the PDU sessions are valid, the UE can immediately implement the correspondence between the application and / or stream communication and the newly established PDU session, or it can be implemented based on the completion of the communication.

[0174] It should be noted that the anchor point of the PDU session in SSC mode 3 can be changed by each device executing the anchor point change process for the PDU session in SSC mode 3.

[0175] Furthermore, in the absence of a specific SSC mode, the default SSC mode is the SSC mode used by the UE and / or the network. Specifically, in the absence of a request for an SSC mode from the application and / or in the absence of a policy for determining the SSC mode for the UE against the application, the default SSC mode can be the SSC mode used by the UE. Additionally, in the absence of a request for an SSC mode from the UE, the default SSC mode can also be the SSC mode used by the network.

[0176] It should be noted that the default SSC mode can be set per DN, per PDN, or per UE and / or per subscriber based on subscriber information and / or operator policies and / or UE policies. Furthermore, the default SSC mode can represent SSC mode 1, SSC mode 2, or SSC mode 3.

[0177] Furthermore, IP address preservation is a technology that enables the continuous use of the same IP address. With IP address preservation supported, the UE can continue to use the same IP address for user data communication even when moving outside the TA (Transportation Unit). In other words, with IP address preservation supported, each device can continue to use the same IP address for user data communication even when the anchor point of the PDU session changes.

[0178] Furthermore, the steering function can be a function that allows a UE capable of using ATSSS to perform steering, switching, or splitting of traffic in an MA PDU session via 3GPP access and non-3GPP access. Here, the steering function may include MPTCP (Multi-Path Transmission Control Protocol) functionality and ATSSS (Access Traffic Steering, Switching, Splitting)-LL (Low-Layer) functionality.

[0179] Furthermore, MPTCP is a bootstrapping function above the IP layer, applied to TCP services. Services using MPTCP are sometimes called MPTCP flows. Additionally, the UE's MPTCP function can also communicate with the UPF's MPTCP proxy function using the user plane of 3GPP access and / or non-3GPP access. Furthermore, the UE can enable MPTCP when requesting an MA PDU session and providing MPTCP capability, and the UPF can enable MPTCP proxy functionality when the UPF agrees to enable MPTCP. The network allocates one IP address / prefix and two IP address / prefixes (also known as link-specific multipath addresses) for the MA PDU session. One of the link-specific multipath addresses is used to establish a subflow via 3GPP access, and the other is used to establish a subflow via non-3GPP access. Furthermore, the link-specific multicast address is only used by the UE's MPTCP function. Routing via N6 is not possible. In addition, the network can send MPTCP proxy information (which may include the MPTCP proxy's IP address, port number, and type) to the UE. Here, the type can be type 1 (transport converter). Furthermore, the network may sometimes indicate a list of applications that should utilize MPTCP functionality to the UE.

[0180] Furthermore, the ATSSS-LL function is a lower-layer bootstrapping function of the IP layer, applicable to all types of services (TCP services, UDP (User Data Protocol) services, Ethernet services, etc.). Sometimes, services using the ATSSS-LL function are referred to as non-MPTCP flows. Additionally, the UPF can also support bootstrapping functions that are the same as or similar to ATSSS-LL. Moreover, the UE's ATSSS-LL function determines uplink service bootstrapping, handover, and splitting based on ATSSS rules and local conditions. Furthermore, the UE can enable the ATSSS-LL function when requesting ATSSS-LL capability from the MA PDU session, and enable the ATSSS-LL function in the UPF when the UE provides ATSSS-LL capability.

[0181] Furthermore, ATSSS rules list more than one ATSSS rule. An ATSSS rule can consist of a rule priority and / or a traffic descriptor and / or an access selection descriptor. Here, the rule priority in the ATSSS rule defines the order in which ATSSS rules are evaluated in the UE. When the UE receives an ATSSS rule (i.e., when it receives one ATSSS rule), it can refer to the rule priorities in each ATSSS rule and evaluate the rules sequentially from the highest priority.

[0182] Furthermore, the service descriptors in ATSSS rules indicate when the ATSSS rules are applied. Service descriptors in ATSSS rules can consist of application descriptors and / or IP descriptors and / or non-IP descriptors. Application descriptors can represent information identifying the application generating the service. IP descriptors can represent information identifying the destination of the IP service. Non-IP descriptors can represent information identifying the destination of non-IP services (such as Ethernet services, unstructured services).

[0183] Furthermore, the access selection descriptor in the ATSSS rule can consist of bootstrapping modes and / or bootstrapping functions. Bootstrapping modes can be information indicating which 3GPP access or non-3GPP access should be assigned to for a Service Data Flow (SDF) service. Additionally, bootstrapping modes can include four modes: Active-Standby, Smallest Delay, Load-Balancing, and Priority-based.

[0184] Furthermore, active standby can take the following modes: Active access and standby access are configured; when active access is available, the Service Data Flow (SDF) is guided for that access; when active access is unavailable, the SDF is switched to standby access. Alternatively, active standby can also take the following mode: With only active access configured and no standby access configured, when active access is available, the Service Data Flow (SDF) is guided for that access; even if active access is unavailable, the SDF cannot be switched to standby access.

[0185] Furthermore, minimum latency can be a mode that directs the Service Data Flow (SDF) to access with the minimum RTT (Round-Trip Time). Additionally, when this mode is set, the UE and UPF can perform measurements to determine the RTT for communication via 3GPP access and the RTT for communication via non-3GPP access.

[0186] Furthermore, load balancing can be a mode that distributes Service Data Flows (SDFs) to both access points. Additionally, when load balancing is specified, information regarding the proportion of Service Data Flows (SDFs) that should be sent via 3GPP access and non-3GPP access can also be included.

[0187] Furthermore, based on priority, the following modes can be used: all services of the Service Data Flow (SDF) are routed to high-priority access until that access is determined to be congested. Alternatively, if the access is determined to be congested, the SDF services are sent not only to high-priority access but also to low-priority access. Moreover, if high-priority access cannot be utilized, all SDF services are sent to low-priority access.

[0188] Furthermore, the guidance function can also indicate which of the MPTCP and ATSSS-LL functions should be used to guide the service data flow (also known as SDF) traffic. Additionally, this information can also be used if the UE supports both MPTCP and ATSSS-LL functions.

[0189] Furthermore, a URSP (UE Route Selection Policy) rule can consist of a list of more than one URSP (UE Route Selection Policy Rule). Each URSP rule can also consist of a rule priority and / or a traffic descriptor and / or a list of route selection descriptors. Here, the rule priority in the URSP rule indicates the order in which the URSP rules are enforced in the UE. When the UE receives more than one URSP rule, it can apply the rules sequentially from the highest priority URSP rule, referring to the rule priority among the URSP rules.

[0190] Furthermore, the service descriptors in URSP rules indicate when the URSP rules are applied. These service descriptors can consist of application descriptors and / or IP descriptors and / or domain descriptors and / or non-IP descriptors and / or DNN (Data Network Name) and / or connection capabilities. Application descriptors can include the OS ID and the OS's application ID. IP descriptors represent information identifying the destination of IP services, such as IP address, IPv6 network prefix, port number, protocol number, etc. Domain descriptors can represent the FQDN (Fully Qualified Domain Name) of the destination. Non-IP descriptors can represent the destination of non-IP services (e.g., Ethernet services, unstructured services). The DNN can be information related to a DNN provided by the application. In addition, connectivity capabilities can represent information provided by the UE's application when the UE requests a connection to the network using a certain capability.

[0191] Furthermore, the list of route selection descriptors in URSP rules can consist of more than one route selection descriptor. Each route selection descriptor can be composed of the rule selection descriptor priority and / or route selection components. The route selection descriptor priority indicates the order in which the route selection descriptors are applied. When a UE receives route selection descriptors, that is, when it receives more than one route selection descriptor, it can apply the descriptors in order of priority, referring to the rule priority in each route selection descriptor. In addition, the route selection descriptor can consist of SSC mode selection and / or network slice selection and / or DNN selection and / or PDU session type selection and / or non-Seamless Offload indication and / or access type preference. Furthermore, SSC mode selection can indicate the routing of application services via a PDU session of a specified SSC mode. Furthermore, network slicing selection can indicate the routing of application services using PDU sessions that support one or more S-NSSAIs as shown. Additionally, DNN selection can indicate the routing of application services using PDU sessions that support one or more DNNs as shown. It should be noted that if a DNN is used in the service descriptor, the routing descriptor may not include DNN selection. Furthermore, PDU session type selection can indicate the routing of application services using PDU sessions that support the PDU session types shown. Furthermore, non-seamless offload indication can indicate the offloading of application services to non-3GPP access. Furthermore, access type preference can indicate the access type for establishing a PDU session when the UE needs to establish a PDU session. Here, access type can refer to 3GPP, non-3GPP, or multi-access. Moreover, multi-access can indicate that the PDU session should be established as a two-party MA PDU session using both 3GPP and non-3GPP access.

[0192] [3.2. Explanation of the identification information used in each embodiment]

[0193] Next, the identification information used in each embodiment will be explained.

[0194] First, the first identification information is the DNN. Alternatively, the first identification information can also be information representing the DNN requested by the UE. It should be noted that the first identification information can be included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session, or it can be excluded from them.

[0195] Furthermore, the second identification information indicates whether the UE supports the ATSSS function. This information can also be expressed as ATSSS capability. Additionally, the second identification information can also indicate whether the UE supports the MPTCP function (a function within ATSSS) and / or whether it supports the ATSSS-LL function (another function within ATSSS). Furthermore, information indicating MPTCP support can also be expressed as MPTCP capability, and information indicating ATSSS-LL support can also be expressed as ATSSS-LL capability. Furthermore, if the UE only supports the MPTCP function, the second identification information can include the MPTCP capability. Furthermore, if the UE only supports the ATSSS-LL function, the second identification information can include the ATSSS-LL capability. Furthermore, if the UE supports both MPTCP and ATSSS-LL functions, the second identification information can include both MPTCP and ATSSS-LL capabilities. It should be noted that the second identification information is preferably included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session, but it may also be excluded from them.

[0196] Furthermore, the third identification information is the PDU session ID. Alternatively, the third identification information can also be information representing the PDU session ID requested by the UE (information used to determine the PDU session). Specifically, when the UE requests the establishment of an MA PDU session, the third identification information can be the PDU session ID used to identify the MA PDU session. It should be noted that the third identification information is preferably included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session.

[0197] Furthermore, the fourth identification information is the PDU session type. Alternatively, the fourth identification information can also be information indicating the type of PDU session requested by the UE. Furthermore, the fourth identification information can be any of IPv4, IPv6, IPv4v6, unstructured, or Ethernet (registered trademark). Additionally, when the UE requests the establishment of an MA PDU session, the fourth identification information can also be the PDU session type for the MA PDU session. It should be noted that the fourth identification information can be included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session, or it can be excluded from them.

[0198] Furthermore, the fifth identification information is the SSC mode. Alternatively, the fifth identification information can also be information indicating the SSC mode requested by the UE. Furthermore, the fifth identification information can be any of SSC mode 1, SSC mode 2, or SSC mode 3. Additionally, when the UE requests the establishment of an MA PDU session, the fifth identification information can also be the SSC mode for the MA PDU session. It should be noted that the fifth identification information can be included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session, or it can be excluded from them.

[0199] Furthermore, the sixth identification information is S-NSSAI. Alternatively, the sixth identification information can also be information representing the S-NSSAI requested by the UE. Furthermore, when the UE requests the establishment of an MA PDU session, the sixth identification information can also be an S-NSSAI that allows access for both parties (3GPP access and non-3GPP access). Specifically, the sixth identification information can be one or more S-NSSAIs included in the allowed NSSAIs (Network-Allowed NSSAIs), which are included in the Registration Accept message received from the AMF during the registration procedure performed by the UE to log in to the 5GS. It should be noted that the sixth identification information can be included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session, or it can be excluded from them.

[0200] Furthermore, the seventh identification information is the request type. Here, the seventh identification information can represent any of the following: an initial request, an existing PDU session, an emergency request, or an existing emergency PDU session. Furthermore, an initial request can be specified when requesting the establishment of a new PDU session. An existing PDU session can be specified when switching between 3GPP and non-3GPP access points or when switching from an existing PDN connection in the EPC to a 5G PDU session. An emergency request can be specified when requesting the establishment of a PDU session for emergency service. An existing emergency PDU session can be specified when switching between 3GPP and non-3GPP access points for emergency service or when switching from an existing PDN connection in the EPC to a 5G PDU session. It should be noted that the seventh identification information may be included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session, or it may not be included in them.

[0201] Furthermore, the eighth identification information is information indicating that the UE requests the establishment of an MA PDU session. This information can also be presented as an MA PDU request indication. It should be noted that the eighth identification information is preferably included in the PDU session establishment request and / or NAS message when the UE requests the establishment of an MA PDU session, but it may also be excluded from them.

[0202] Furthermore, the ninth identification information may be information that combines the content of two or more of the first to eighth identification information mentioned above. It should be noted that the ninth identification information may be included in the PDU session establishment request message and / or NAS message when the UE requests the establishment of an MA PDU session, or it may not be included therein.

[0203] Furthermore, the eleventh identification information is the DNN. Alternatively, the eleventh identification information can also represent information about the DNN determined by the network. It should be noted that the eleventh identification information may be included in the ATSSS container IE (Information Element) and / or PDU session establishment accept message and / or NAS message when the network permits the establishment of an SA PDU session or MA PDU session, or it may not be included.

[0204] Furthermore, the eleventh identification information may also be information determined by the network based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. Additionally, the eleventh identification information may be the same as the first identification information.

[0205] Furthermore, the twelfth identification information indicates whether the network supports the ATSSS function. This information can also be expressed as ATSSS capability. Additionally, the twelfth identification information can also indicate whether the network supports the MPTCP function (a function of ATSSS) and / or the ATSSS-LL function (another function of ATSSS). Furthermore, information indicating MPTCP support can also be expressed as MPTCP capability, and information indicating ATSSS-LL support can also be expressed as ATSSS-LL capability. Furthermore, the network can include MPTCP capability in the twelfth identification information if only MPTCP is supported. Furthermore, the network can include ATSSS-LL capability in the twelfth identification information if only ATSSS-LL is supported. Furthermore, the network can include both MPTCP and ATSSS-LL capabilities in the twelfth identification information if both MPTCP and ATSSS-LL are supported. It should be noted that the twelfth identification information is preferably included in the PDU session establishment accept message and / or NAS message when the network allows the establishment of an MA PDU session, but it may not be included therein. Furthermore, even when the network does not allow the establishment of MA PDU sessions, when the establishment of SA PDU sessions is allowed, the twelfth identification information is preferably included in the ATSSS container IE (Information Element) and / or PDU session establishment acceptance message and / or NAS message, but may not be excluded from them.

[0206] In addition, the twelfth identification information may also be information determined by the network based on the first to ninth identification information and / or the network's capability information and / or the operator's policies and / or the network's status and / or the user's login information, etc.

[0207] Furthermore, the thirteenth identification information is the PDU session ID. Alternatively, the thirteenth identification information can also be information representing the PDU session ID determined by the network (information used to identify the PDU session). Specifically, the thirteenth identification information can be the PDU session ID used for SA PDU sessions or the PDU session ID used for MA PDU sessions. More specifically, when the network allows the establishment of a MA PDU session, the thirteenth identification information can be the PDU session ID used to identify the MA PDU session. Furthermore, when the network allows the establishment of an SA PDU session, the thirteenth identification information can be the PDU session ID used to identify the SA PDU session. It should be noted that the thirteenth identification information is preferably included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message when the network allows the establishment of an SA PDU session or MA PDU session.

[0208] Furthermore, the thirteenth identification information can also be information determined by the network based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. Additionally, the thirteenth identification information can be the same as the third identification information.

[0209] Furthermore, the fourteenth identification information is the PDU session type. Alternatively, the fourteenth identification information can also be information indicating the PDU session type determined by the network. The fourteenth identification information can also be any of IPv4, IPv6, IPv4v6, unstructured, or Ethernet (registered trademark). Furthermore, the fourteenth identification information can also be information indicating the PDU session type corresponding to the established PDU session. Additionally, when the network allows the establishment of an SA PDU session, the fourteenth identification information can be the PDU session type for the SA PDU session. Furthermore, when the network allows the establishment of an MA PDU session, the fourteenth identification information can be the PDU session type for the MA PDU session. It should be noted that the fourteenth identification information is preferably included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message when the network allows the establishment of an SAPDU session or MA PDU session.

[0210] Furthermore, the fourteenth identification information can also be information determined by the network based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. Additionally, the fourteenth identification information can be the same as the fourth identification information.

[0211] Furthermore, the fifteenth identification information is the SSC mode. Alternatively, the fifteenth identification information can also be information representing the SSC mode determined by the network. Furthermore, the fifteenth identification information can be any of SSC mode 1, SSC mode 2, and SSC mode 3. Additionally, the fifteenth identification information can also be information representing the SSC mode corresponding to the established PDU session. Furthermore, when the network allows the establishment of an SA PDU session, the fifteenth identification information can be the SSC mode for the SA PDU session. Furthermore, when the network allows the establishment of an MA PDU session, the fifteenth identification information can be the SSC mode for the MA PDU session. It should be noted that the fifteenth identification information is preferably included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message when the network allows the establishment of an SA PDU session or MA PDU session.

[0212] Furthermore, the fifteenth identification information may also be information determined by the network based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. Additionally, the fifteenth identification information may be the same as the fifth identification information.

[0213] Furthermore, the sixteenth identification information is S-NSSAI. Alternatively, the sixteenth identification information can also represent S-NSSAI determined by the network. Furthermore, the sixteenth identification information can also represent S-NSSAI corresponding to the established PDU session. Additionally, when the network allows the establishment of an MA PDU session, the sixteenth identification information can be an S-NSSAI allowing access from both parties (3GPP access and non-3GPP access). Furthermore, when the network allows the establishment of an SA PDU session, the sixteenth identification information can be an S-NSSAI allowing access from only one party (3GPP access or non-3GPP access). Specifically, the sixteenth identification information can be one or more S-NSSAIs included in the allowed NSSAIs (network-allowed NSSAIs), which are included in the Registration Accept message received from the AMF during the registration procedure performed by the UE to log in to the 5GS. It should be noted that the sixteenth identification information may be included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message when the network allows the establishment of SA PDU or MA PDU sessions, or it may not be included in them.

[0214] Furthermore, the sixteenth identification information can also be information determined by the network based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. Additionally, the sixteenth identification information can be the same as the sixth identification information.

[0215] Furthermore, the seventeenth identification information is information indicating the reason (cause) for disallowing part of the UE's request. Additionally, the seventeenth identification information can also be represented as a 5GSM cause value.

[0216] For example, the seventeenth identification information could be information indicating the reason for disallowing the establishment of an MA PDU session. Furthermore, the seventeenth identification information could also be information indicating the reason for disallowing the establishment of user plane resources for both parties' access (3GPP access and non-3GPP access) constituting an MA PDU session. Additionally, the seventeenth identification information could be information indicating the reason for disallowing the establishment of user plane resources for only one party's access (3GPP access or non-3GPP access) constituting an MA PDU session. Furthermore, the seventeenth identification information could also be information indicating the reason for disallowing the establishment of user plane resources for both parties' access (3GPP access and non-3GPP access) constituting an MA PDU session, but allowing the establishment of a SAPDU session for only one party's access (3GPP access or non-3GPP access). It should be noted that the seventeenth identification information may be included in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, or it may not be included in them.

[0217] In addition, the content of the seventeenth identification information may include, for example, operator-determined barring, insufficient resources, missing or unknown DNN, unknown PDU session type, user authentication or authorization failure, request rejected or unspecified, service option not supported, requested service option not subscribed, PTI (Procedure Transaction Identity) already in use, network failure, outside of LADN (Local Area Data Network) service area, PDU session type only allowed for IPv4, PDU session type only allowed for IPv6, PDU session does not exist, and insufficient resources for a specific slice and DNN. The following are possible causes of errors: (1) for a specific slice and DNN; (2) unsupported SSC mode; (3) insufficient resources for a specific slice; (4) missing or unknown DNN in a slice; (5) maximum data rate per UE for user-plane integrity protection is too low; (6) protocol errors.

[0218] Furthermore, the eighteenth identification information is information indicating the value of the backoff timer. Additionally, the eighteenth identification information can also indicate a period during which the execution of a certain process is prohibited from being repeated after its completion, or a different process is to be executed. Specifically, during a certain process, a UE that receives the eighteenth identification information can only re-execute the process after the period indicated by the eighteenth identification information has elapsed since the process's completion. It should be noted that the eighteenth identification information may or may not be included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message.

[0219] Furthermore, the nineteenth identification information is information indicating the access type. Alternatively, the nineteenth identification information may also be information indicating the access corresponding to the allowed user plane resources, provided that the establishment of an MA PDU session is permitted through the network (allowing the establishment of user plane resources for access to both parties). Here, the access corresponding to the allowed user plane resources can be 3GPP access and / or non-3GPP access.

[0220] Furthermore, the nineteenth identification information can also represent access information corresponding to the allowed user plane resources, or access information corresponding to the denied user plane resources, provided that the network allows the establishment of an MA PDU session (allowing only the establishment of user plane resources for access to one party (denying the establishment of user plane resources for access to the other party)). The access corresponding to the allowed user plane resources can be 3GPP access or non-3GPP access, and the access corresponding to the denied user plane resources can also be 3GPP access or non-3GPP access.

[0221] Furthermore, the nineteenth identification information can also represent access information corresponding to the allowed SA PDU session or access information corresponding to the rejected SA PDU session, in cases where the network rejects the establishment of an MA PDU session but allows the establishment of an SA PDU session for one party's access. The access corresponding to the allowed SA PDU session can be 3GPP access or non-3GPP access, and the access corresponding to the rejected SA PDU session can be 3GPP access or non-3GPP access.

[0222] Furthermore, the nineteenth identification information may also be determined based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. It should be noted that the nineteenth identification information may be included in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, or it may not be included therein.

[0223] Furthermore, the twentieth identification information is an ATSSS rule. Alternatively, the twentieth identification information can also be determined based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. It should be noted that the twentieth identification information is preferably included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message when allowing the establishment of an MA PDU session.

[0224] Furthermore, the twenty-first identification information indicates whether the network has permitted the establishment of an MA PDU session. Additionally, the twenty-first identification information may be determined based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. It should be noted that the twenty-first identification information may be included in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, or it may not be included in them.

[0225] Furthermore, the twenty-second identification information indicates whether the network has permitted the establishment of an SA PDU session. Additionally, the twenty-second identification information may be determined based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. It should be noted that the twenty-second identification information may be included in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, or it may not be included therein.

[0226] Furthermore, the twenty-third identification information can also be information that combines two or more of the identification information from the eleventh to twenty-second identification information described above. It should be noted that the twenty-third identification information may or may not be included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message.

[0227] Furthermore, the 31st identification information indicates whether the network has rejected the establishment of an MA PDU session. Additionally, the 31st identification information may be determined based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. It should be noted that the 31st identification information may or may not be included in the PDU session establishment rejection message and / or NAS message.

[0228] Furthermore, the 32nd identification information indicates whether the network has rejected the establishment of an SA PDU session. Additionally, the 32nd identification information may be determined based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. It should be noted that the 32nd identification information may or may not be included in the PDU session establishment rejection message and / or NAS message.

[0229] Furthermore, the thirty-third identification information is the PDU session ID. Alternatively, the thirty-third identification information can also be information representing the PDU session ID determined by the network (information used to determine the PDU session). Specifically, the thirty-third identification information can be the PDU session ID included when the network rejects the UE's request. More specifically, when the network rejects the establishment of an MA PDU session, the thirteenth identification information can be the PDU session ID used to identify the MA PDU session. Furthermore, when the network rejects the establishment of an SAP PDU session, the thirty-third identification information can be the PDU session ID used to identify the SA PDU session. It should be noted that the thirty-third identification information is preferably included in the PDU session establishment rejection message and / or NAS message when the network rejects the establishment of an SA PDU session or MA PDU session.

[0230] Furthermore, the thirty-third identification information can also be information determined by the network based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. Additionally, the thirty-third identification information can be the same as the thirteenth identification information.

[0231] Furthermore, the thirty-fourth identification information is SSC mode. Alternatively, the thirty-fourth identification information can also be information indicating the SSC modes supported by the network. Furthermore, the thirty-fourth identification information can also be information indicating whether the network supports SSC mode 1, SSC mode 2, and SSC mode 3 respectively. It should be noted that the thirty-fourth identification information is preferably included in the PDU session establishment rejection message and / or NAS message.

[0232] Furthermore, the thirty-fourth identification information may also be information determined by the network based on the first to ninth identification information and / or network capability information and / or operator policies and / or network status and / or user login information, etc. In addition, the content of the thirty-fourth identification information may be the same as the content of the seventeenth identification information.

[0233] Furthermore, the 35th identification information is information indicating the reason (cause) for disallowing the UE's request. Additionally, the 35th identification information can also be represented as a 5GSM cause value.

[0234] For example, the 35th identification information can be information indicating the reason for disallowing the establishment of an MA PDU session. Furthermore, the 35th identification information can also be information indicating the reason for disallowing the establishment of user plane resources for both parties (3GPP access and non-3GPP access) constituting an MA PDU session. Additionally, the 35th identification information can also be information indicating the reason for disallowing the establishment of an SA PDU session. It should be noted that the 35th identification information may or may not be included in the PDU session establishment rejection message and / or NAS message.

[0235] Furthermore, the 36th identification information is information indicating the value of the backoff timer. Additionally, the 36th identification information can also be information indicating a period during which the execution of a certain process is prohibited after its completion, or a different process is to be executed. Specifically, in a certain process, a UE that receives the 36th identification information can only execute the process again after the period indicated by the 36th identification information has elapsed since the process was completed.

[0236] Furthermore, the thirty-seventh identification information may also be information that combines two or more of the identification information from the thirty-first to thirty-sixth identification information described above. It should be noted that the thirty-seventh identification information may or may not be included in the PDU session establishment rejection message and / or NAS message.

[0237] [4. MA PDU Session Establishment Process]

[0238] Next, use Figure 6 This document provides an overview of the MA PDU session establishment procedure performed to establish an MA PDU session for a specific DN. It should be noted that, hereinafter, the MA PDU session establishment procedure will sometimes be referred to simply as the PDU session establishment procedure, or sometimes simply as this procedure.

[0239] The MA PDU session establishment process is the procedure performed by each device in the 5GS to establish an MA PDU session. It should be noted that each device can initiate the MA PDU session establishment process at any time after the login process is completed and the device is in a logged-in state. Specifically, the MA PDU session establishment process can begin when the UE logs into the 5GS via 3GPP access and / or non-3GPP access.

[0240] In addition, each device sometimes establishes an MA PDU session when the MA PDU session establishment process completes normally. Specifically, each device sometimes establishes user plane resources for the access (3GPP access and non-3GPP access) of both parties constituting the MA PDU session. In addition, each device sometimes establishes user plane resources for the access (3GPP access or non-3GPP access) of only one party constituting the MA PDU session.

[0241] In addition, sometimes the devices are unable to establish an MA PDU session even when the MA PDU session establishment process is completed normally, but instead establish an SA PDU session for one party's access (3GPP access or non-3GPP access).

[0242] In addition, if the MA PDU session establishment process is not completed normally (abnormally completed), the device will be unable to establish an MA PDU session or SA PDU session.

[0243] Furthermore, the MA PDU session establishment process can also be initiated by the UE. In addition, each device can establish multiple MA PDU sessions by executing the MA PDU session establishment process multiple times, or it can establish more than one SA PDU session and more than one MA PDU session.

[0244] The following describes the scenario where a UE logs into the 5GS via 3GPP access or non-3GPP access, and initiates an MA PDU session establishment process for a specific DN to establish an MA PDU session via either 3GPP or non-3GPP access. This explanation assumes that the 3GPP access, non-3GPP access, and 5GC (5G Core Network) are all managed / operated by the same operator, but it can also be applied to scenarios where different operators operate the network. Furthermore, a simple case is assumed where the UE does not establish a SAPDU session or MA PDU session (i.e., it does not have user plane resources via either 3GPP or non-3GPP access), but this can also be applied to cases where a SAPDU session and / or MA PDU session is established.

[0245] The UE can determine to start the MA PDU session establishment process based on information pre-stored in the UE and / or information received in advance from the access network and / or information received in advance from the core network (including identification information received during the login process and / or URSP rules received in advance from the PCF, etc.).

[0246] First, the UE initiates the MA PDU session establishment process by sending NAS messages (S900), (S902), and (S904) containing a PDU session establishment request message to the SMF via the 5G AN and AMF.

[0247] Specifically, the UE sends a NAS message (S900) including a PDU session establishment request message to the AMF via the N1 interface and the 5G AN.

[0248] Here, 5G AN includes 3GPP access (also known as 3GPP access network) and non-3GPP access (also known as non-3GPP access network). Specifically, when the UE sends NAS messages via 3GPP access, the UE sends the NAS message to the AMF via base station device_110. Furthermore, when the UE sends NAS messages via untrusted non-3GPP access, the UE sends the NAS message to the AMF via base station devices_120 and N3IWF. Additionally, when the UE sends NAS messages via trusted non-3GPP access, the UE sends the NAS message to the AMF via TNAP and TNGF. Thus, the communication path to the AMF changes depending on which access the UE uses to send the NAS message, but the communication path from the AMF to the SMF can be the same.

[0249] Furthermore, the UE can include at least one of the first to ninth identification information in the PDU session establishment request message and / or NAS message. However, the UE can also include it in control messages that are different from these control messages, such as control messages from layers lower than the NAS layer (e.g., RRC layer, MAC layer, RLC layer, PDCP layer). Here, the NAS message can be an uplink NAS transport (UL NAS TRANSPORT) message.

[0250] In addition, the UE can notify the network side of a request by sending at least one of the first to ninth identification information in the PDU session establishment request message and / or NAS message.

[0251] Here, the sixth identification information can be the S-NSSAI that the network allows for access to both parties (3GPP access and non-3GPP access) during the registration procedure.

[0252] Furthermore, the UE notifies the network side of the following situations by including the eighth identification information and the seventh identification information indicating an initial request in the PDU session establishment request message and / or NAS message: a PDU session establishment request message has been sent to establish a new MA PDU session, and / or the ATSSS-LL function and / or MPTCP function have been applied to guide the service of the MA PDU session. Additionally, the UE may also notify the network side of whether it supports the ATSSS function and / or whether it supports the MPTCP function and / or ATSSS-LL function by including the second identification information in the PDU session establishment request message and / or NAS message. Furthermore, the UE may also notify the network side of the PDU session ID for the MA PDU session by including the third identification information in the PDU session establishment request message and / or NAS message. Finally, the UE may also notify the network side of the PDU session type, SSC mode, and S-NSSAI of the MA PDU session requested by the UE by including the fourth to sixth identification information in the PDU session establishment request message and / or NAS message.

[0253] When AMF receives a NAS message (S900) that includes a PDU session establishment request message, it can extract the PDU session establishment request message from the NAS message and identify the various identification information included in the request made by the UE and / or the PDU session establishment request message and / or the NAS message.

[0254] It should be noted that the AMF can reject the establishment of an MA PDU session if the UE logs into the access of either party, but the access of either party does not allow the S-NSSAI shown in the sixth identification information received from the UE. Furthermore, the AMF can also reject the establishment of an MA PDU session if the ATSSS function is not supported.

[0255] When rejecting the establishment of an MA PDU session, the AMF can send a PDU session establishment rejection message and / or NAS message to the UE, including information indicating rejection of the MA PDU session establishment. In this case, the AMF does not need to send the identification information included in the PDU session establishment request message and / or NAS message to the SMF.

[0256] In addition, when rejecting the establishment of an MA PDU session, the AMF can also send a message to the SMF indicating that the establishment of the MA PDU session is rejected, or the SMF can request the UE to send a PDU session establishment rejection message and / or a NAS message that includes the message indicating that the establishment of the MA PDU session is rejected.

[0257] Furthermore, each device can halt the process when the establishment of an MA PDU session is rejected. Additionally, rejection of MA PDU session establishment can also occur when the MA PDU session establishment process fails to complete normally.

[0258] It should be noted that AMF may also skip these checks and proceed to the next step.

[0259] Then, the AMF selects the SMF as the transmission destination for the various identification information included in the PDU session establishment request message and / or NAS message (S902). It should be noted that the AMF can select the SMF as the transmission destination based on the various identification information and / or subscriber information and / or network capability information and / or operator policies and / or network status and / or user login information and / or the context maintained by the AMF included in the PDU session establishment request message and / or NAS message. Furthermore, the AMF can also select an SMF that supports ATSSS functionality. Here, we assume that SMF_22, which supports MA PDU sessions, has been selected.

[0260] The AMF transmits a PDU session establishment request message and / or NAS message (S904) to the selected SMF via the N11 interface. Additionally, the AMF can also send information to the SMF indicating that the UE has logged into access from both parties.

[0261] When receiving PDU session establishment request messages and / or NAS messages transmitted from the AMF, the SMF can identify various identification information included in the PDU session establishment request messages and / or NAS messages requested by the UE. Furthermore, the SMF can perform third-condition judgment. Third-condition judgment can be used to determine whether to accept the UE's request. In third-condition judgment, the SMF determines whether the third condition is true or false. If the third condition is true, the SMF begins... Figure 6 In process (A), if the third condition is determined to be false, the process begins. Figure 6 (B) process.

[0262] It should be noted that the third condition determination can be performed based on the identification information and / or subscription information and / or network capability information and / or operator policies and / or network status and / or user login information and / or the context maintained by the SMF included in the PDU session establishment request message and / or NAS message. For example, the third condition determination may be true if the network allows the UE's request. Alternatively, it may be false if the network does not allow the UE's request. Furthermore, the third condition determination may be true if the network and / or devices within the UE's connection destination support the requested function, and false if the requested function is not supported. Moreover, the third condition determination may be true if the transmitted and received identification information is allowed, and false if the transmitted and received identification information is not allowed.

[0263] Alternatively, the third condition can be true if, when the UE begins this procedure to request the establishment of an MA PDU session, the establishment of the MA PDU session is permitted (the establishment of user plane resources for access to both parties is permitted). Alternatively, the third condition can be true if, when the UE begins this procedure to request the establishment of an MA PDU session, the establishment of the MA PDU session is permitted (the establishment of user plane resources for access to only one party is permitted (the establishment of user plane resources for access to the other party is denied)). Alternatively, even if, when the UE begins this procedure to request the establishment of an MA PDU session, the establishment of the MA PDU session is denied (the establishment of user plane resources for access to both parties is denied), the establishment of an SA PDU session for access to only one party is permitted, and the third condition is still true. Alternatively, when the UE initiates this procedure to request the establishment of an MA PDU session, if the establishment of the MA PDU session is rejected (the establishment of user plane resources for access to both parties is rejected), and the establishment of an SA PDU session (for access to both parties) is also rejected, the third condition determination is false. It should be noted that the conditions determining the truth or falsity of the third condition determination are not limited to the conditions described above.

[0264] Next, the step of determining if the third condition is true is... Figure 6 The steps of process (A) will be explained.

[0265] First, the SMF can select a PCF. For example, if the seventh identification information indicates an initial request—that is, if this procedure has been performed to establish a new PDU session (SA PDU session or MA PDU session)—the SMF can select an appropriate PCF based on information received from the AMF. For instance, the SMF can select a PCF that supports ATSSS functionality. Furthermore, the SMF can also use the selected PCF when the seventh identification information is an existing PDU session or an existing emergency PDU session. That is, the SMF can choose not to select a PCF, or it can choose a different PCF.

[0266] Next, the SMF can send the identification information included in the PDU session establishment request message and / or NAS message received from the AMF to the PCF (S905).

[0267] Furthermore, the SMF can also send "information indicating permission to establish an MA PDU session" and / or "information indicating permission to establish user plane resources for two-party access" and / or "information indicating access information (access type) corresponding to the permitted user plane resources" to the PCF, provided that the establishment of an MA PDU session is permitted (where the establishment of user plane resources for two-party access is permitted). Here, "information indicating access information (access type) corresponding to the permitted user plane resources" can be 3GPP access or non-3GPP access.

[0268] Furthermore, the SMF may also send "information indicating permission to establish an MA PDU session" and / or "information indicating permission to establish a user plane resource for one party" and / or "information indicating rejection of the establishment of a user plane resource for the other party" and / or "information indicating access type corresponding to the permitted user plane resource" and / or "information indicating access type corresponding to the rejected user plane resource" to the PCF, provided that the establishment of an MA PDU session is permitted (only the establishment of user plane resources for one party's access is permitted, and the establishment of user plane resources for the rejected user plane resource is permitted). Here, it is possible that when the "information indicating access type corresponding to the permitted user plane resource" is 3GPP access, the "information indicating access type corresponding to the rejected user plane resource" is non-3GPP access. Alternatively, it is also possible that when the "information indicating access type corresponding to the permitted user plane resource" is non-3GPP access, the "information indicating access type corresponding to the rejected user plane resource" is 3GPP access.

[0269] Furthermore, even in the case of rejecting the establishment of an MA PDU session (rejecting the establishment of user plane resources for access to both parties), if the establishment of an SA PDU session for access to one party is permitted, the SMF may send "information indicating rejection of MA PDU session establishment" and / or "information indicating rejection of user plane resources for MA PDU sessions for access to both parties" and / or "information indicating permission to establish an SA PDU session for access to one party" and / or "information indicating rejection of SA PDU sessions for access to the other party" and / or "information indicating access information (access type) corresponding to the user plane resources used for the rejected MA PDU session" and / or "information indicating access information (access type) corresponding to the permitted SA PDU session" and / or "information indicating access information (access type) corresponding to the rejected SA PDU session" to the PCF. Here, "information (access type) corresponding to the user plane resources used for the rejected MA PDU session" can be 3GPP access or non-3GPP access. Alternatively, when the "Information (Access Type) Representing Access Corresponding to an Allowed SA PDU Session" is 3GPP access, the "Information (Access Type) Representing Access Corresponding to an Denied SA PDU Session" is non-3GPP access. Alternatively, when the "Information (Access Type) Representing Access Corresponding to an Allowed SA PDU Session" is non-3GPP access, the "Information (Access Type) Representing Access Corresponding to a Denied SA PDU Session" is 3GPP access.

[0270] Next, the PCF can identify the UE's request for the establishment of an MA PDU session and / or the content of various identification information when receiving various identification information sent from the SMF.

[0271] It should be noted that the PCF can also make the same judgments as those made by the SMF based on information received from the SMF and / or operator policies and / or subscription information. In this case, the PCF can send the same information to the SMF as the SMF can send to the PCF.

[0272] In addition, PCF can also skip the above judgment if it detects that the judgment has been made in SMF (or it can be skipped).

[0273] Alternatively, the above judgment can be omitted in the SMF and performed only in the PCF. In this case, the information sent from the SMF to the PCF may not only include the identification information included in the PDU session establishment request message and / or NAS message received from the AMF. That is, even if the above judgment is performed in the SMF, it is not necessary to send additional information to the PCF. Furthermore, for the information sent from the PCF to the SMF, the same information can be sent from the PCF to the SMF as the information sent from the SMF to the PCF.

[0274] Furthermore, PCF can generate PCC rules for MA PDU sessions while allowing the establishment of MA PDU sessions. Additionally, PCF can also generate policies for SA PDU sessions instead of MA PDU sessions while allowing the establishment of SA PDU sessions.

[0275] For example, if the PCF detects that the establishment of an MA PDU session is permitted based on information received from the SMF (allowing the establishment of user plane resources for two-party access), it can generate PCC rules for the MA PDU session for the permitted user plane resources. Furthermore, the PCF can also generate PCC rules for the MA PDU session for the permitted user plane resources based on information received from the SMF and / or the aforementioned determination in the PCF that allows the establishment of an MA PDU session (allowing the establishment of user plane resources for two-party access).

[0276] Furthermore, the PCF can also generate PCC rules for MA PDU sessions that are allowed to be established, based on information received from the SMF (allowing the establishment of user plane resources for access only to one party (rejecting the establishment of user plane resources for access to the other party)). Additionally, the PCF can also generate PCC rules for MA PDU sessions that are allowed to be established, based on information received from the SMF and / or the aforementioned determination in the PCF (allowing the establishment of user plane resources for access only to one party (rejecting the establishment of user plane resources for access to the other party)).

[0277] Furthermore, if the PCF detects that it rejects the establishment of an MA PDU session based on information received from the SMF (rejecting the establishment of user plane resources for access to both parties), but allows the establishment of an SA PDU session for access to one party, it may not generate PCC rules for the MA PDU session, but instead generate a policy for the SA PDU session that is allowed to be established. Moreover, even if it rejects the establishment of an MA PDU session based on information received from the SMF and / or the aforementioned judgment in the PCF (rejecting the establishment of user plane resources for access to both parties), but allows the establishment of an SA PDU session for access to one party, the PCF may not generate PCC rules for the MA PDU session, but instead generate a policy for the SA PDU session that is allowed to be established.

[0278] Furthermore, the PCF can send PCC rules to the SMF when generating PCC rules for MA PDU sessions. Additionally, the PCF can also send information to the SMF indicating permission to establish an MA PDU session, or it can send PCC rules to indicate permission to establish an MA PDU session.

[0279] In addition, the PCF can also send the policy to the SMF when a policy for the SA PDU session is generated.

[0280] SMF can identify this information when receiving various types of information from PCF.

[0281] Furthermore, upon receiving the PCC rule from the PCF, the SMF generates the ATSSS rule (20th identification information) and the N4 rule based on the PCC rule. Here, the ATSSS rule controls the MA PDU session information sent from the SMF to the UE, and the N4 rule controls the MA PDU session information sent from the SMF to the UPF. Additionally, the SMF can also manage (map) the PCC rule, ATSSS rule, and N4 rule in a corresponding manner.

[0282] Furthermore, the SMF can also determine the SSC mode (fifteenth identification information) applied to MA PDU sessions and / or SA PDU sessions. Additionally, when the fourth identification information indicates any of IPv4, IPv6, or IPv4v6, the SMF can assign IP addresses or IP prefixes for MA PDU sessions and / or SA PDU sessions. Furthermore, when the fourth identification information indicates unstructured, the SMF can assign IPv6 addresses for MA PDU sessions and / or SA PDU sessions. Furthermore, when the fourth identification information indicates Ethernet (registered trademark), the SMF may not assign MAC addresses or IP addresses to MA PDU sessions and / or SA PDU sessions.

[0283] Next, the SMF selects the UPF as the destination for establishing either an MA PDU session or an SA PDU session, and sends an N4 session establishment request message to the selected UPF via the N4 interface (S906). Here, the N4 session establishment request message can be used when performing this procedure to establish a new PDU session. Alternatively, an N4 session correction request message can be used instead of the N4 session establishment request message when performing this procedure to correct an existing PDU session. Here, the SMF can select one or more UPFs based on the identification information and / or subscriber information and / or network capability information and / or operator policies and / or network status and / or user login information and / or the context maintained by the SMF, obtained from receiving the PDU session establishment request message. It should be noted that when multiple UPFs are selected, the SMF can send N4 session establishment request messages to each UPF. Furthermore, when the establishment of an MA PDU session is allowed, the SMF can select a UPF that supports ATSSS functionality. Furthermore, when the establishment of an SAP PDU session is allowed, the SMF can select a UPF that supports SA PDU sessions, or it can select a UPF that supports ATSSS functionality. Here, UPF_230 is selected.

[0284] Alternatively, N4 rules can be included in the N4 session establishment request message when the establishment of an MA PDU session is permitted.

[0285] When the UPF receives an N4 session establishment request message from the SMF via the N4 interface (S906), it can identify the content of the information received from the SMF. Furthermore, the UPF generates context for the MA PDU or SA PDU session. The UPF is also configured to act according to the N4 rules received from the SMF. That is, the UPF determines which access point should be routed to for downlink traffic in the established MAPDU session. Moreover, based on the received N4 session establishment request message and / or the generated context for the MAPDU or SA PDU session, the UPF sends an N4 session establishment response message to the SMF via the N4 interface (S908).

[0286] When the SMF receives an N4 session establishment response message from the UPF via the N4 interface as a response message to the N4 session establishment request message (S908), it can identify the content of the information received from the UPF. Furthermore, the SMF can also perform address allocation for the UE based on the reception of the PDU session establishment request message and / or the selection of the UPF and / or the reception of the N4 session establishment response message.

[0287] Furthermore, based on the receipt of the PDU session establishment request message and / or the selection of the UPF and / or the receipt of the N4 session establishment response message and / or the completion of the address allocation assigned to the UE, the SMF sends a PDU session establishment accept message (S910) (S912) to the UE via the AMF, including the ATSSS container IE.

[0288] Specifically, when the SMF sends a PDU session establishment accept message to the AMF via the N11 interface (S910), the AMF that receives the message sends a NAS message containing a PDU session establishment accept message with an ATSSS container IE to the UE via the N1 interface and the 5G AN (S912).

[0289] Here, 5G AN includes both 3GPP access and non-3GPP access. Specifically, when the AMF sends NAS messages via 3GPP access, the AMF sends the NAS messages to the UE via base station device_110. Furthermore, when the AMF sends NAS messages via untrusted non-3GPP access, the AMF sends the NAS messages to the UE via N3IWF and base station device_120. Additionally, when the AMF sends NAS messages via trusted non-3GPP access, the AMF sends the NAS messages to the UE via TNGF and TNAP.

[0290] In addition, AMF preferably uses the same access as the access that receives NAS messages from the UE to send NAS messages to the UE, but it can also send NAS messages to the UE via a different access.

[0291] Furthermore, a PDU session establishment accept message can be a response message to a PDU session establishment request. Additionally, a PDU session establishment accept message can also indicate acceptance of a PDU session establishment. Moreover, a NAS message can also be a downlink NAS transport (DL NAS transport) message.

[0292] Here, the SMF and / or AMF may indicate acceptance of at least a portion of the UE's request based on the PDU session establishment request message by sending an ATSSS container IE and / or a PDU session establishment accept message and / or a NAS message.

[0293] Furthermore, the SMF and / or AMF may include at least one of the eleventh to twenty-third identification information in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message. The SMF and / or AMF can inform the UE of the content of these identification information by sending at least one of these identification information.

[0294] For example, when MA PDU session establishment is permitted (allowing the establishment of user plane resources for two-way access), identification information eleventh to sixteenth and nineteenth to twenty-first and / or twenty-third identification information can be included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message. Here, the eleventh identification information can also be the same as the first identification information. Furthermore, the twelfth identification information can represent MPTCP capability and / or ATSSS-LL capability in the network. Furthermore, the thirteenth identification information can also be the same as the third identification information. Furthermore, the fourteenth identification information can also be the same as the fourth identification information. Furthermore, the fifteenth identification information can also be the same as the fifth identification information. Furthermore, the sixteenth identification information can also be the same as the sixth identification information. Furthermore, the nineteenth identification information can represent 3GPP access and non-3GPP access. Furthermore, the twentieth identification information can represent ATSSS rules. Furthermore, the twenty-first identification information can indicate that the network allows the establishment of MA PDU sessions. Furthermore, the twenty-third identification information can represent a combination of the contents of two or more identification information from the eleventh to twenty-first identification information.

[0295] Thus, the establishment of an MA PDU session and / or the establishment of user plane resources for both parties, and / or the access type corresponding to the allowed user plane resources, can be notified to the UE by including specific identification information from identification information eleven through twenty-three in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message. For example, this can be done by including identification information twenty-one, identification information thirteen (PDU session ID), and identification information nineteen (3GPP access and non-3GPP access) indicating that the network allows the establishment of the MA PDU session in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message.

[0296] Alternatively, the UE can be notified of the permission to establish a MAPDU session and / or the permission to establish user plane resources for both parties and / or the access type corresponding to the permitted user plane resources by including specific identification information from identification information 11 to 23 in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, excluding specific identification information. For example, this can be done by including identification information 21 and 13 (PDU session ID) indicating that the network allows the establishment of a MAPDU session in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, but excluding identification information 19 (3GPP access and non-3GPP access).

[0297] Furthermore, if the establishment of an MA PDU session is permitted (establishment of user plane resources for access by only one party is permitted (establishment of user plane resources for access by the other party is denied)), identification information eleven to twenty-first and / or twenty-third identification information may be included in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message. Here, the eleventh identification information may also be the same as the first identification information. Furthermore, the twelfth identification information may represent the MPTCP capability and / or ATSSS-LL capability in the network. Furthermore, the thirteenth identification information may also be the same as the third identification information. Furthermore, the fourteenth identification information may also be the same as the fourth identification information. Furthermore, the fifteenth identification information may also be the same as the fifth identification information. Furthermore, the sixteenth identification information may also be the same as the sixth identification information. Furthermore, the seventeenth identification information may represent the reason for disallowing the establishment of user plane resources for unilateral access (3GPP access or non-3GPP access) constituting an MA PDU session. Furthermore, the eighteenth identification information may represent the value of the backoff timer. Furthermore, the nineteenth identification information may represent 3GPP access or non-3GPP access. Furthermore, the twentieth identification information can represent an ATSSS rule. Additionally, the twenty-first identification information can indicate that the network permits the establishment of an MA PDU session. Furthermore, the twenty-third identification information can represent content that combines the contents of two or more identification information from the eleventh to twenty-first identification information.

[0298] Thus, the UE can be notified of the permission to establish an MA PDU session and / or the permission to establish user plane resources for one party's access and / or the denial of user plane resources for the other party's access by including specific identification information from identification information eleven through twenty-three in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message. For example, this can be done by including identification information twenty-one, identification information thirteen (PDU session ID), and identification information nineteen (3GPP access or non-3GPP access) indicating that the network allows the establishment of the MA PDU session in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message.

[0299] Furthermore, the SMF may also include identification information eleventh to nineteenth and twenty-first to twenty-second identification information and / or twenty-third identification information in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message when it rejects the establishment of MA PDU session (rejects the establishment of user plane resources for access to both parties), but allows the establishment of SA PDU session for access to one party. Here, the eleventh identification information may also be the same as the first identification information. Furthermore, the twelfth identification information may indicate the MPTCP capability and / or ATSSS-LL capability in the network. Furthermore, the thirteenth identification information may also be the same as the third identification information. Furthermore, the fourteenth identification information may also be the same as the fourth identification information. Furthermore, the fifteenth identification information may also be the same as the fifth identification information. Furthermore, the sixteenth identification information may also be the same as the sixth identification information. Furthermore, the seventeenth identification information may indicate the reason for rejecting the establishment of MA PDU session for user plane resources for access to both parties. Furthermore, the eighteenth identification information may indicate the value of the backoff timer. Furthermore, the nineteenth identification information may indicate 3GPP access or non-3GPP access. Furthermore, the twenty-first identification information can indicate that the network rejects the establishment of an MA PDU session. Furthermore, the twenty-second identification information can indicate that the network rejects the establishment of an SA PDU session. Furthermore, the twenty-third identification information can indicate a combination of two or more identification information from the eleventh to nineteenth and twenty-first to twenty-second identification information. Thus, by including specific identification information from the eleventh to twenty-third identification information in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, the UE can be notified of the rejection of MA PDU session establishment and / or the rejection of user plane resources for MA PDU sessions for access to both parties and / or the permission to establish an SAPDU session for access to one party and / or the rejection of SA PDU sessions for access to the other party and / or the access type corresponding to the user plane resources used for the rejected MA PDU session and / or the access type corresponding to the allowed SA PDU session and / or the access type corresponding to the rejected SA PDU session. For example, these can be communicated to the UE by including, in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message, twenty-first identification information indicating that the network rejects the establishment of the MA PDU session, twenty-second identification information indicating that the network allows the establishment of the SA PDU session, and nineteenth identification information (3GPP access or non-3GPP access).

[0300] It should be noted that the SMF and / or AMF can send this identification information to indicate that the network supports various functions, or to indicate that they are receiving a request from the UE.

[0301] It should be noted that the SMF and / or AMF can select and determine which identification information to include in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message based on the received identification information and / or subscriber information and / or network capability information and / or operator policies and / or network status and / or user login information and / or the context maintained by the SMF and / or AMF.

[0302] Furthermore, the SMF and / or AMF can also indicate the reason for rejecting a portion of the UE's request by including the seventeenth identification information in the ATSSS container IE and / or PDU session establishment accept message and / or NAS message. The UE can identify the reason for rejecting a portion of the UE's request by receiving the information indicating that a portion of the UE's request has been rejected.

[0303] In addition, the UE receives a NAS message (S912) from the AMF via the N1 interface, which includes a PDU session establishment acceptance message containing an ATSSS container IE. The UE can identify the request and / or the content of each identification information of the UE accepting the PDU session establishment request message by receiving the ATSSS container IE and / or the PDU session establishment acceptance message and / or the NAS message.

[0304] Furthermore, the UE can determine whether to allow the establishment of an MA PDU session (allowing the establishment of user plane resources for access to both parties), allow the establishment of an MA PDU session (allowing the establishment of user plane resources for access to only one party (rejecting the establishment of user plane resources for access to the other party)), or reject the establishment of an MA PDU session (rejecting the establishment of user plane resources for access to both parties) based on the information shown in the identification information included in the ATSSS container IE and / or PDU session establishment acceptance message and / or NAS message, but allow the establishment of an SA PDU session for access to only one party.

[0305] If the UE determines that the establishment of an MA PDU session is permitted (allowing the establishment of user plane resources for access to both parties), it can apply the ATSSS rules shown in the twentieth identification information to become a state in which the MA PDU session can communicate with the DN by using user plane resources for access to both parties (3GPP access and / or non-3GPP access).

[0306] Furthermore, if the UE determines that the establishment of an MA PDU session is permitted (the establishment of user plane resources for access to one party is permitted only (the establishment of user plane resources for access to the other party is denied)), it can apply the ATSSS rules shown in the twentieth identification information and determine the access corresponding to the available user plane resources based on the nineteenth identification information, thus becoming a state in which the MA PDU session can communicate with the DN by using the user plane resources of that access (3GPP access or non-3GPP access).

[0307] In addition, if the UE determines that the establishment of an MA PDU session is rejected (the establishment of user plane resources for access to both parties is rejected) but the establishment of an SA PDU session for access to one party is allowed, it can determine the access corresponding to the available PDU session based on the nineteenth identification information, and become a state in which the UE can communicate with the DN through the SAPDU session of that access (3GPP access or non-3GPP access).

[0308] As described above, each device can complete the process based on the sending and receiving of various messages in this process (e.g., sending and receiving PDU session establishment accept messages and / or sending and receiving N4 session establishment request messages and / or sending and receiving N4 session establishment response messages). Figure 6 The (A) process (the MA PDU session establishment process can be completed normally). In Figure 6 When process (A) is completed, the UE can be in a state where an MA PDU session or an SA PDU session has been established. That is, the UE can be in a state where it can communicate with the DN using an MA PDU session or an SA PDU session.

[0309] Furthermore, even if the UE determines that the establishment of an MA PDU session is permitted (allowing the establishment of user plane resources for two-party access) and has established user plane resources for two-party access, the UE can execute this procedure again to further request the establishment of the MA PDU session. For example, the UE can attempt to establish an MA PDU session by immediately executing this procedure. Furthermore, when this procedure is executed again, when the UE sends a PDU session establishment request message and / or NAS message including third identification information, the third identification information is preferably set to a value different from the third identification information included in the PDU session establishment request message and / or NAS message in the previous procedure and the thirteenth identification information included in the PDU session establishment acceptance message and / or NAS message in the previous procedure. Furthermore, it is preferable that the thirteenth identification information included in the PDU session establishment acceptance message and / or NAS message in this procedure is the same as the third identification information included in the PDU session establishment request message and / or NAS message in this procedure. Furthermore, it is preferable that the thirty-third identification information included in the PDU session establishment rejection message and / or NAS message in this procedure is the same as the third identification information included in the PDU session establishment request message and / or NAS message in this procedure. In addition, in these cases, and in cases where more than two MA PDU sessions are not allowed, the UE may not be able to execute this procedure again.

[0310] Furthermore, if the UE determines that the establishment of an MA PDU session is permitted (the establishment of user plane resources for access only to one party is permitted (the establishment of user plane resources for access to the other party is rejected)), and only user plane resources for access to one party are established, the UE can also execute this procedure again to establish the user plane resources that were previously rejected. For example, the UE can attempt to establish user plane resources for the rejected user plane resources by immediately executing this procedure via the access corresponding to the rejected user plane resources without receiving the eighteenth identification information. Alternatively, the UE can attempt to establish user plane resources for the rejected user plane resources by executing this procedure via the access corresponding to the rejected user plane resources after the period specified by the eighteenth identification information has elapsed, upon receiving the eighteenth identification information. Furthermore, when this procedure is executed again, when the UE sends a PDU session establishment request message and / or NAS message including at least one of the first to ninth identification information, the first, third to sixth identification information is preferably set to be the same as the first, third to sixth identification information included in the PDU session establishment request message and / or NAS message in the previous procedure. This is to clarify on the network side that the request is for an additional MA PDU session established during a previous PDU session establishment process. Furthermore, it is preferable that the eleventh, thirteenth to sixteenth identification information included in the PDU session establishment acceptance message and / or NAS message in this process is the same as the eleventh, thirteenth to sixteenth identification information included in the PDU session establishment request message and / or NAS message in this process. Furthermore, it is preferable that the thirty-third identification information included in the PDU session establishment rejection message and / or NAS message in this process is the same as the third identification information included in the PDU session establishment request message and / or NAS message in this process. Alternatively, if more than two MA PDU sessions are not allowed, the UE cannot execute this procedure again.

[0311] Furthermore, if the SMF and / or PCF determine in the previous process that the establishment of an MA PDU session is permitted (establishment of user plane resources for access to only one party is permitted (establishment of user plane resources for access to the other party is denied)), the network side may instruct the UE to begin the MA PDU session establishment procedure after the completion of this procedure. For example, the SMF and / or PCF can instruct the UE to begin the MA PDU session establishment procedure by sending a control message to the UE including the seventeenth identification information sent in the previous process and / or information indicating the reason for canceling the seventeenth identification information sent in the previous process. It should be noted that this procedure can also be referred to as a network-requested MA PDU session establishment procedure or a network-initiated MA PDU session establishment procedure.

[0312] Furthermore, even if the establishment of an MA PDU session is rejected (rejection of user plane resource establishment for access to both parties), but the establishment of an SA PDU session for access to one party is allowed, the UE can re-execute this procedure after the SA PDU session is established. For example, the UE can attempt to establish an MA PDU session by immediately executing this procedure without receiving the eighteenth identification information. Alternatively, the UE can attempt to establish an MA PDU session by executing this procedure after the period specified by the eighteenth identification information has elapsed, provided that the eighteenth identification information has been received. Furthermore, when the UE sends a PDU session establishment request message and / or NAS message including third identification information during the re-execution of this procedure, the third identification information is preferably set to a value different from the third identification information included in the PDU session establishment request message and / or NAS message in the previous procedure and the thirteenth identification information included in the PDU session establishment acceptance message and / or NAS message in the previous procedure. Moreover, it is preferable that the thirteenth identification information included in the PDU session establishment acceptance message and / or NAS message in this procedure is the same as the third identification information included in the PDU session establishment request message and / or NAS message in this procedure. Furthermore, it is preferred that the 33rd identification information included in the PDU session establishment rejection message and / or NAS message during this process is the same as the 3rd identification information included in the PDU session establishment request message and / or NAS message during this process.

[0313] Furthermore, if the SMF and / or PCF determine in the previous process that the establishment of an MA PDU session is rejected (rejecting the establishment of user plane resources for access to both parties), but the establishment of an SA PDU session for access to one party is allowed, then after the completion of this process, the network side instructs the UE to start the MA PDU session establishment procedure. For example, the SMF and / or PCF can instruct the UE to start the MA PDU session establishment procedure by sending a control message to the UE including the seventeenth identification information sent in the previous process and / or information indicating the reason for canceling the seventeenth identification information sent in the previous process. It should be noted that this procedure can also be called a network-requested MA PDU session establishment procedure or a network-initiated MA PDU session establishment procedure.

[0314] Next, regarding Figure 6 The steps of process (B) will be explained. As described above, the process can begin with the rejection of the establishment of an MA PDU session (rejection of the establishment of user plane resources for access to both parties) and the rejection of the establishment of an SA PDU session (for access to both parties). Figure 6 The process of (B).

[0315] The SMF sends a PDU session establishment reject message to the UE via the AMF (S922)(S924). Specifically, the SM sends the PDU session establishment reject message to the AMF via the N11 interface (S922). When the AMF receives the PDU session establishment request message from the SMF (S922), it uses the N1 interface to send a NAS message including the PDU session establishment reject message to the UE (S924).

[0316] The SMF and / or AMF may also include at least one of the thirty-first to thirty-seventh identification information in the PDU session establishment rejection message and / or NAS message. The SMF and / or AMF can inform the UE of the content of these identification information by sending at least one of these identification information.

[0317] It should be noted that a PDU session establishment rejection message can also be a NAS message. Furthermore, a PDU session establishment rejection message can simply indicate a rejection of the establishment of an MA PDU session and / or an SA PDU session.

[0318] Here, the SMF can indicate that the UE's request based on the PDU session establishment request message has been rejected by sending a PDU session establishment rejection message. Furthermore, the SMF can include information indicating the reason for the rejection in the PDU session establishment rejection message, or it can express the reason for the rejection by sending the reason itself. Subsequently, the UE can identify the reason for the rejection by receiving the information indicating the reason for the rejection. It should be noted that the reason for rejection can be information indicating that the content shown in the identification information received by the SMF is not allowed.

[0319] The UE can identify the UE's request to reject the PDU session establishment request message and the contents of various identification information included in the PDU session establishment rejection message by receiving the PDU session establishment rejection message.

[0320] As described above, each device can complete the process based on the sending and receiving of each message in this process (e.g., sending and receiving PDU session establishment rejection messages). Figure 6 The (B) process (can also complete the MA PDU session establishment process abnormally). In Figure 6 When process (B) is completed, the UE may be in a state where no new MA PDU session or SA PDU session has been established. That is, the UE may be in a state where it cannot communicate with the DN.

[0321] Furthermore, the UE may also re-execute this procedure if it determines that the establishment of an MA PDU session is rejected (rejection of the establishment of user plane resources for access to both parties) and the establishment of an SA PDU session (for access to both parties) is also rejected. For example, the UE may attempt to establish an MA PDU session by executing this procedure immediately without receiving the 36th identification information. Alternatively, the UE may attempt to establish an MA PDU session by executing this procedure after the period specified by the 36th identification information has elapsed if the 36th identification information is received.

[0322] [5. Other]

[0323] The program operating in the apparatus of this invention can be a program that controls a central processing unit (CPU) or other computer to perform functions in order to achieve the functions of the embodiments of this invention. The program or the information processed by the program is temporarily stored in volatile memory such as random access memory (RAM) or non-volatile memory such as flash memory, hard disk drive (HDD) or other storage device systems.

[0324] It should be noted that programs used to implement the functions of the embodiments involved in this invention can also be recorded in a computer-readable recording medium. This can be achieved by reading the program recorded in the recording medium into a computer system and executing it. The term "computer system" here refers to a computer system built into a device, including hardware such as an operating system and peripherals. Furthermore, the "computer-readable recording medium" can be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a medium for short-term dynamic storage of programs, or other computer-readable recording media.

[0325] Furthermore, the functional blocks or features of the apparatus used in the above embodiments can be installed or executed by electronic circuits such as integrated circuits or multiple integrated circuits. Circuits designed to perform the functions described in this specification may include: general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic elements, discrete gate or transistor logic, discrete hardware components, or combinations thereof. General-purpose processors may be microprocessors, or processors, controllers, microcontrollers, or state machines of conventional types. The aforementioned electronic circuits may be constructed from digital circuits or analog circuits. Furthermore, in cases where advancements in semiconductor technology have led to the emergence of integrated circuit technologies that replace current integrated circuits, one or more embodiments of the present invention may also utilize new integrated circuits based on such technologies.

[0326] It should be noted that the present invention is not limited to the embodiments described above. While one example of the device is described in the embodiments, the present invention is not limited thereto and can be applied to fixed or non-movable electronic devices installed indoors or outdoors, such as AV equipment, kitchen equipment, cleaning / washing equipment, air conditioning equipment, office equipment, vending machines, and other household appliances, etc.

[0327] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the specific configuration is not limited to these embodiments, and design changes that do not depart from the spirit of the present invention are also included. Furthermore, the present invention can be modified in various ways within the scope of the technical solutions shown, and embodiments obtained by appropriately combining technical solutions disclosed in different embodiments are also included within the technical scope of the present invention. In addition, it also includes configurations obtained by replacing elements that have the same effect as those described in the above embodiments with each other.

Claims

1. A user equipment (UE), characterized in that, The user equipment (UE) includes a control unit and a transceiver unit, wherein... The transceiver unit is configured to receive first information from the Access and Mobility Management Function (AMF) indicating whether the network supports Access Traffic Steering, Switching, Splitting (ATSSS). The control unit is configured to determine, based on the first information, whether the ATSSS is supported by the network. If the control unit determines, based on the first information, that the ATSSS is supported by the network, the control unit initiates the Protocol Data Unit (PDU) session establishment process. When the transceiver receives a PDU session establishment accept message including an ATSSS container information element (IE) through a first access for one of the 3GPP and non-3GPP access protocols, the control unit identifies the case where a multi-access MA PDU session has been established, and the case where the MA PDU session is established only in the first access protocol, and the case where the user plane resources are used to establish the MA PDU session. If the control unit determines, based on the first information, that the ATSSS is not supported by the network, the control unit is further configured not to initiate the PDU session establishment process to establish the MA PDU session.

2. The UE according to claim 1, characterized in that, The ATSSS container IE includes ATSSS rules.

3. The UE according to claim 1, characterized in that, When the control unit logs into 3GPP access or non-3GPP access, it initiates the PDU session establishment process.

4. A communication control method executed by a user equipment (UE), the communication control method comprising: The Access and Mobility Management Function (AMF) receives initial information indicating whether the network supports Access Traffic Steering, Switching, and Splitting (ATSSS). Based on the first information, it is determined whether the ATSSS is supported by the network. If, based on the first information, it is determined that the ATSSS is supported by the network, the Protocol Data Unit (PDU) session establishment process begins, and When the UE receives a PDU session establishment accept message including the ATSSS container information element (IE) through first access for either 3GPP or non-3GPP access, it identifies the case where a multi-access MAPDU session has been established, and the case where the MAPDU session is established only in the first access. If it is determined based on the first information that the ATSSS is not supported by the network, the PDU session establishment process is not initiated to establish the MA PDU session.

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