WO2020105547A1

WO2020105547A1 - User device

Info

Publication number: WO2020105547A1
Application number: PCT/JP2019/044796
Authority: WO
Inventors: 雄大河崎; 真史新本; 靖夫菅原
Original assignee: シャープ株式会社
Priority date: 2018-11-19
Filing date: 2019-11-15
Publication date: 2020-05-28
Also published as: JP2020088473A

Abstract

Provided is a communications means for achieving functions for URLLC requiring highly reliable and/or low latency communications in a 5G system. This user device provides a communications means capable of URLLC functions in a 5G system, as a result of: using a registration procedure to send registration request messages including information identifying other user devices and receiving registration acceptance messages including UE RG, DNN for URLLC, and S–NSSAI; and using a first PDU session establishment procedure to send PDU session establishment request messages including information that indicates that the SSC mode for a PDU session for URLLC is SSC mode 1 and establish the PDU session on the basis of receiving a PDU session establishment acceptance message as a response to the PDU session establishment request message.

Description

User equipment

The present invention relates to a user device. The present application claims priority based on Japanese Patent Application No. 2018-2166496 filed in Japan on Nov. 19, 2018, the contents of which are incorporated herein by reference.

3GPP (3rd Generation Partnership Project) has begun to study the system architecture of the next generation, that is, 5GS (5G System), which is the 5th generation (5G) mobile communication system, and discusses support for new procedures and new functions. (See Non-Patent Document 1 and Non-Patent Document 2). In 5GS (5G System), a new core network, 5GC (5G Core Network), is being considered in order to provide a wide variety of services. Furthermore, discussions have been started to support URLLC (Ultra-Reliable and Low Latency Communications) with 5GS, which requires high-reliability and / or low-delay communication (see Non-Patent Document 3).

However, how to realize URLLC with 5GS is still under study, and it is not clear. In particular, it is not clear what kind of procedure or information is exchanged to realize the function for URLLC.

One aspect of the present invention has been made in view of the above circumstances, and an object thereof is to provide means for realizing a function for URLLC in 5GS.

A user device according to an embodiment of the present invention includes a control unit and a transmission / reception unit, the control unit executes a registration procedure, and the transmission / reception unit receives information for identifying another user device in the registration procedure. Send a registration request message that includes the UE Reliability Group (UERG), DLC (Data Network Name) for URLLC (Ultra-Reliable and Low Latency Communications), and S-NSSAI (Single Network Slice Selection Assistance Information). Is received.

According to one aspect of the present invention, it is possible to use the function for URLLC in 5GS.

FIG. 1 is a diagram explaining an outline of a mobile communication system 1. FIG. 3 is a diagram illustrating a detailed configuration of the mobile communication system 1. FIG. 3 is a diagram for explaining the outline of the mobile communication system 2. FIG. 3 is a diagram illustrating a detailed configuration of the mobile communication system 2. It is a figure explaining the apparatus structure of UE. It is a figure explaining the structure of the access network apparatus (gNB) in 5GS. It is a figure explaining the structure of the core network apparatus (AMF / SMF / UPF) in 5GS. It is a figure explaining the apparatus configuration of a device. It is a figure explaining a registration procedure. It is a figure explaining the PDU session establishment procedure. It is a figure explaining the change procedure of the PDU session anchor which provides the PDU session of SSC mode3.

In the following, the mobile communication system, the configuration of each device, the term / identification information and the procedure used in each embodiment, which have many common parts to each embodiment, are described, and then each embodiment for implementing the present invention is described. explain.

[1. Overview of mobile communication systems]
Here, the mobile communication system will be described.

First, FIG. 1 is a diagram for explaining an outline of the mobile communication system 1, and FIG. 2 is a diagram for explaining a detailed configuration of the mobile communication system 1. In the first to fourth embodiments described below, the mobile communication system 1 shown in FIGS. 1 and 2 is used.

In Fig. 1, it is stated that the mobile communication system 1 is composed of a UE (User Equipment) _10, an access network_100, a core network_200, and a DN (Data Network) _300. It should be noted that these devices and networks may be described by omitting symbols such as UE, access network, core network, and DN.

Further, in FIG. 2, UE_10, gNB (gNodeB) _110, gNB_112, AMF (Access and Mobility Management Function) _210, SMF (Session Management Function) _220, SMF_222, SMF_224, UPF (User Plane Function) _230, UPF_232, UPF_234. , DN_300 and other devices / network functions, and interfaces that connect these devices / network functions to each other are described. Note that these devices / network functions may be described by omitting symbols such as UE, gNB, AMF, SMF, UPF, and DN. Note that gNB_110 may be referred to as a master gNB or a master base station, and gNB_112 may be referred to as a secondary gNB or a second base station.

Further, FIG. 3 is a diagram for explaining an outline of the mobile communication system 2, and FIG. 4 is a diagram for explaining a detailed configuration of the mobile communication system 2. In the fifth to eighth embodiments described later, the mobile communication system 2 shown in FIGS. 3 and 4 is used.

FIG. 3 describes that the mobile communication system 2 is composed of UE_10, UE_12, device_20, access network_100, core network_200, and DN_300. Note that these devices / networks may be described by omitting symbols such as UE, device, access network, core network, and DN.

Further, in FIG. 4, UE_10, UE_12, device_20, gNB_110, gNB_112, AMF_210, AMF_212, SMF_220, SMF_222, SMF_224, UPF_230, UPF_232, UPF_232, DN_300 and the like device and network functions, and these devices and network functions. The interfaces connecting the components to each other are described. Note that these devices and network functions may be described by omitting symbols such as UE, device, gNB, AMF, SMF, UPF, and DN.

Note that 5GS (5G System), which is a 5G system, is configured to include a UE, an access network, and a core network, but may further include a DN.

UE is a device connectable to a network service via 3GPP access (also referred to as 3GPP access network, 3GPPAN) and / or non-3GPP access (also referred to as non-3GPP access network, non-3GPPAN). is there. The UE may be a terminal device capable of wireless communication such as a mobile phone or a smart phone, and may be a terminal device capable of connecting to an EPS (Evolved Packet System) or 5GS. The UE may include a UICC (Universal Integrated Circuit Card) and an eUICC (Embedded UICC). The UE may be expressed as a user device or a terminal device.

Also, the access network may be referred to as a 5G access network (5GAN). 5GAN consists of NG-RAN (NG Radio Access Network) and / or non-3GPP access network. One or more gNBs are arranged in the NG-RAN. The gNB is a node that provides an NR (New Radio) user plane and a control plane to the UE, and is a node that connects to the 5GC via an NG interface (including an N2 interface or an N3 interface). That is, the gNB is a base station device newly designed for 5GS and has a function different from that of the base station device (eNB) used in EPS that is a 4G system. When there are a plurality of gNBs, the gNBs are connected to each other by, for example, the Xn interface.

Also, in the following, NG-RAN may be referred to as 3GPP access. A wireless LAN access network or non-3GPPAN may be referred to as non-3GPP access. In addition, the nodes arranged in the access network may be collectively referred to as NG-RAN nodes.

Also, in the following, a device included in the access network and / or a device included in the access network may be referred to as an access network device.

Also, the core network supports 5GC (5G Core Network). For example, AMF, UPF, SMF, etc. are arranged in the 5GC. Here, 5GC may be expressed as 5GCN (5G Core Network).

Also, in the following, the core network and / or devices included in the core network may be referred to as core network devices.

The core network may be an IP mobile communication network operated by a mobile network operator (MNO) that connects an access network and a DN, or a mobile that operates and manages the mobile communication system 1. It may be a core network for a physical communication carrier or a core network for a virtual mobile communication carrier or a virtual mobile communication service provider such as MVNO (Mobile Virtual Network Operator) and MVNE (Mobile Virtual Network Enabler). ..

Also, the DN may be a DN that provides communication services to the UE. The DN may be configured as a packet data service network or may be configured for each service. Further, the DN may include the connected communication terminal. Therefore, connecting with the DN may be connecting with a communication terminal or a server device arranged in the DN. Further, transmitting / receiving the user data to / from the DN may be transmitting / receiving the user data to / from a communication terminal or a server device arranged in the DN.

In the following, the access network, the core network, at least a part of the DN, and / or one or more devices included in these may be referred to as a network or a network device. That is, a network and / or network device sending and / or receiving messages and / or performing procedures means that the access network, the core network, at least part of the DN, and / or one or more devices contained therein , Sending and receiving messages, and / or performing procedures.

UE can also connect to the access network. The UE can also connect to the core network via the access network. Further, the UE can connect to the DN via the access network and the core network. That is, the UE can send and receive (communicate) user data with the DN. When transmitting / receiving the user data, not only IP (Internet Protocol) communication but also non-IP communication may be used.

Here, IP communication is data communication using IP, and data is transmitted and received by IP packets. An IP packet is composed of an IP header and a payload part. The payload part may include the device / function included in the EPS and the data transmitted / received by the device / function included in the 5GS. In addition, non-IP communication is data communication that does not use IP, and data is transmitted and received in a format different from the structure of an IP packet. For example, the non-IP communication may be data communication realized by transmitting and receiving application data to which an IP header is not added, or by adding another header such as a MAC header or an Ethernet (registered trademark) frame header to the UE. User data to be transmitted / received may be transmitted / received.

[2. Configuration of each device]
Next, the configuration of each device (UE and / or access network device and / or core network device) used in each embodiment will be described with reference to the drawings. Each device may be configured as physical hardware, logical (virtual) hardware configured on general-purpose hardware, or configured as software. May be done. Further, at least part (including all) of the functions of each device may be configured as physical hardware, logical hardware, or software.

Each storage unit (storage unit_430, storage unit_540, storage unit_640, storage unit_730) in each device / function that appears below is, for example, a semiconductor memory, an SSD (Solid State Drive), It consists of HDD (Hard Disk Drive). In addition, each storage unit includes not only the information originally set from the shipping stage, but also a device / function other than its own device / function (for example, UE and / or access network device, and / or core network device, and / or Or, it is possible to store various information transmitted / received between PDN and / or DN). Further, each storage unit can store identification information, control information, flags, parameters, etc. included in control messages transmitted and received in various communication procedures described later. Further, each storage unit may store such information for each UE.

[2.1. UE device configuration]
First, a device configuration example of a UE used in each embodiment will be described with reference to FIG. The UE includes a control unit_400, an antenna_410, a transmission / reception unit_420, and a storage unit_430. The control unit_400, the transmission / reception unit_420, and the storage unit_430 are connected via a bus. The transceiver_420 is connected to the antenna_410.

The control unit_400 is a functional unit that controls the operation / function of the entire UE. Note that the control unit_400 may process all functions that the other functional units (transmission / reception unit_420, storage unit_430) of the UE do not have. The control unit_400 realizes various processes in the UE by reading and executing various programs stored in the storage unit_430 as needed.

The transmitting / receiving unit_420 is a functional unit for wirelessly communicating with the base station device (gNB) in the access network via the antenna_410. That is, the UE can transmit / receive user data and / or control information to / from the access network device and / or the core network device and / or the DN by using the transmission / reception unit_420.

Describing in detail with reference to FIG. 2, the UE can communicate with the base station device (gNB) in the 5GAN by using the transceiver unit_420. In addition, the UE can transmit and receive AMF and NAS (Non-Access-Stratum) messages via the N1 interface by using the transceiver unit_420. However, since the N1 interface is a logical interface, the communication between the UE and AMF is actually performed via the gNB in 5GAN.

The storage unit_430 is a functional unit for storing programs, user data, control information, etc. necessary for each operation of the UE.

[2.2. GNB equipment configuration]
Next, a device configuration example of the gNB used in each embodiment will be described with reference to FIG. The gNB is composed of a control unit_500, an antenna_510, a network connection unit_520, a transmission / reception unit_530, and a storage unit_540. The control unit_500, the network connection unit_520, the transmission / reception unit_530, and the storage unit_540 are connected via a bus. The transceiver_530 is connected to the antenna_510.

The control unit_500 is a functional unit that controls the operation / function of the entire gNB. The control unit_500 may process all the functions that the other functional units (network connection unit_520, transmission / reception unit_530, storage unit_540) of the gNB do not have. The control unit_500 realizes various processes in the gNB by reading and executing various programs stored in the storage unit_540 as necessary.

-Network connection unit_520 is a functional unit for the gNB to communicate with AMF and / or UPF. That is, the gNB can transmit / receive user data and / or control information to / from the AMF and / or UPF using the network connection unit 520.

The transceiver_530 is a functional unit for wirelessly communicating with the UE via the antenna 510. That is, the gNB can transmit / receive user data and / or control information to / from the UE by using the transmitting / receiving unit_530.

To explain in detail with reference to FIG. 2, the gNB in the 5GAN can communicate with the AMF via the N2 interface and the UPF via the N3 interface by using the network connection unit 520. Can communicate with. Also, the gNB can communicate with the UE by using the transmitting / receiving unit_530.

The storage unit_540 is a functional unit for storing programs, user data, control information, etc. necessary for each operation of gNB.

[2.3. AMF device configuration]
Next, an example of an AMF device configuration used in each embodiment will be described with reference to FIG. The AMF is composed of a control unit_600, a network connection unit_620, and a storage unit_640. The control unit_600, the network connection unit_620, and the storage unit_640 are connected via a bus. The AMF may be a node that handles the control plane.

The control unit_600 is a functional unit that controls the operation / function of the entire AMF. The control unit_600 may process all the functions that the other function units (network connection unit_620, storage unit_640) of the AMF do not have. The control unit _600 realizes various processes in the AMF by reading and executing various programs stored in the storage unit _640 as necessary.

The network connection unit 620 is a function unit for the AMF to connect with the base station device (gNB) and / or SMF and / or PCF, and / or UDM and / or SCEF in the 5GAN. That is, AMF, by using the network connection unit 620, between the base station device (gNB) in 5GAN, and / or SMF, and / or PCF, and / or UDM, and / or SCEF, the user. Data and / or control information can be sent and received.

Explaining in detail with reference to FIG. 2, the AMF in the 5GC can communicate with the gNB through the N2 interface by using the network connection unit _620, and with the UDM through the N8 interface. It can communicate, can communicate with SMF via N11 interface, and can communicate with PCF via N15 interface. In addition, the AMF can send and receive NAS messages with the UE via the N1 interface by using the network connection unit_620. However, since the N1 interface is logical, the communication between UE and AMF is actually performed via 5GAN.

The storage unit 640 is a functional unit for storing programs, user data, control information, etc. necessary for each AMF operation.

AMF is a function for exchanging control messages with RAN using N2 interface, a function for exchanging NAS messages with UE using N1 interface, a function for encryption and integrity protection of NAS messages, and registration management. (Registration management; RM) function, connection management (CM) function, reachability management (Reachability management) function, mobility management (UE) mobility management function, SM between UE and SMF (Session Management) N2 for message transfer function, access authentication (Access Authentication, Access Authorization) function, security anchor function (SEA; Security Anchor Functionality), security context management (SCM; Security Context Management) function, N3IWF (Non-3GPP Interworking Function) It has a function to support an interface, a function to support transmission and reception of NAS signals with a UE via N3IWF, a function to authenticate a UE connected via N3IWF, and the like.

In addition, registration management manages the RM status of each UE. The RM state may be synchronized between the UE and AMF. The RM state includes a non-registration state (RM-DEREGISTERED state) and a registration state (RM-REGISTERED state). In the RM-DEREGISTERED state, since the UE is not registered in the network, the AMF cannot reach the UE because the UE context in AMF does not have valid location information and routing information for the UE. Further, in the RM-REGISTERED state, since the UE is registered in the network, the UE can receive a service that requires registration with the network. The RM state may be expressed as a 5GMM state. In this case, the RM-DEREGISTERED state may be expressed as a 5GMM-DEREGISTERED state, and the RM-REGISTERED state may be expressed as a 5GMM-REGISTERED state.

In other words, 5GMM-REGISTERED may be a state in which each device has established a 5GMM context or a PDU session context. When each device is 5GMM-REGISTERED, UE_10 may start transmission / reception of user data and control messages, or may respond to paging. Furthermore, when each device is 5GMM-REGISTERED, UE_10 may execute a registration procedure other than the registration procedure for initial registration and / or a service request procedure.

Furthermore, 5GMM-DEREGISTERED, each device may be in a state where 5GMM context is not established, UE_10 location information may not be known to the network, the network reaches UE_10 It may be impossible. When each device is 5GMM-DEREGISTERED, UE_10 may start the registration procedure or may establish the 5GMM context by executing the registration procedure.

In connection management, the CM status of each UE is managed. The CM state may be synchronized between the UE and AMF. The CM states include a non-connection state (CM-IDLE state) and a connection state (CM-CONNECTED state). In the CM-IDLE state, the UE is in the RM-REGISTERED state but does not have a NAS signaling connection established with the AMF via the N1 interface. In the CM-IDLE state, the UE does not have the N2 interface connection (N2 connection) and the N3 interface connection (N3 connection). On the other hand, in the CM-CONNECTED state, it has a NAS signaling connection established with the AMF via the N1 interface. Further, in the CM-CONNECTED state, the UE may have an N2 interface connection (N2 connection) and / or an N3 interface connection (N3 connection).

Furthermore, in connection management, the CM status in 3GPP access and the CM status in non-3GPP access may be managed separately. In this case, the CM state in 3GPP access may include a non-connection state in 3GPP access (CM-IDLE state over 3GPP access) and a connection state in 3GPP access (CM-CONNECTED state over 3GPP access). Furthermore, as the CM state in non-3GPP access, there are non-connection state in non-3GPP access (CM-IDLE state over non-3GPP access) and connection state in non-3GPP access (CM-CONNECTED state over over non-3GPP access) ) There may be. Incidentally, the non-connection state may be expressed as an idle mode, and the connection state mode may be expressed as a connected mode.

Note that the CM state may be expressed as 5GMM mode. In this case, the non-connection state may be expressed as a 5GMM non-connection mode (5GMM-IDLE mode), or the connection state may be expressed as a 5GMM connection mode (5GMM-CONNECTED mode). Furthermore, the non-connection state in 3GPP access may be expressed as 5GMM non-connection mode in 3GPP access (5GMM-IDLE mode over 3GPP access), and the connection state in 3GPP access may be expressed in 5GMM connection mode in 3GPP access (5GMM- CONNECTED mode over 3GPP access). Furthermore, the non-connection state in non-3GPP access may be expressed as 5GMM non-connection mode (5GMM-IDLE mode over non-3GPP access) in non-3GPP access, and the connection state in non-3GPP access is non- -It may be expressed as 5GMM connection mode in 3GPP access (5GMM-CONNECTED mode over non-3GPP access). The 5GMM non-connection mode may be expressed as an idle mode, and the 5GMM connection mode may be expressed as a connected mode.

Also, one or more AMFs may be placed in the core network. The AMF may be an NF that manages one or more NSI (Network Slice Instance). The AMF may be a shared CP function (CCNF; Control Plane Network Function) that is shared between multiple NSIs.

Note that N3IWF is a device and / or function arranged between the non-3GPP access and the 5GC when the UE connects to the 5GS via the non-3GPP access.

[2.4. SMF device configuration]
Next, a device configuration example of the SMF used in each embodiment will be described with reference to FIG. The SMF is composed of a control unit_600, a network connection unit_620, and a storage unit_640. The control unit_600, the network connection unit_620, and the storage unit_640 are connected via a bus. The SMF may be a node that handles the control plane.

The control unit_600 is a functional unit that controls the operation / function of the entire SMF. The control unit_600 may process all the functions that the other function units (network connection unit_620, storage unit_640) of the SMF do not have. The control unit _600 realizes various processes in the SMF by reading and executing various programs stored in the storage unit _640 as necessary.

The network connection part 620 is a function part for SMF to connect with AMF and / or UPF, and / or PCF, and / or UDM. That is, the SMF can transmit / receive user data and / or control information to / from the AMF and / or the UPF, and / or the PCF, and / or the UDM by using the network connection unit 620.

Referring to FIG. 2 in detail, the SMF in the 5GC can communicate with the AMF via the N11 interface and the UPF via the N4 interface by using the network connection_620. It can communicate, can communicate with the PCF through the N7 interface, and can communicate with the UDM through the N10 interface.

The storage unit_640 is a functional unit for storing programs, user data, control information, etc. necessary for each SMF operation.

SMF is a session management function such as establishment / modification / release of PDU session, IP address allocation for UE and its management function, UPF selection and control function, and appropriate destination (destination). ), A function to set up UPF for routing traffic, a function to send and receive the SM part of NAS message, a function to notify that downlink data has arrived (Downlink Data Notification), AN via N2 interface via AMF. It has a function to provide SM information (specific to each AN) specific to AN, a function to determine SSC mode (Session and Service Continuity mode) for a session, and a roaming function.

[2.5. UPF equipment configuration]
Next, a device configuration example of the UPF used in each embodiment will be described with reference to FIG. The UPF is composed of a control unit_600, a network connection unit_620, and a storage unit_640. The control unit_600, the network connection unit_620, and the storage unit_640 are connected via a bus. The UPF may be a node that handles the control plane.

The control unit_600 is a functional unit that controls the operation / function of the entire UPF. Note that the control unit_600 may process all the functions that the other functional units (network connection unit_620, storage unit_640) of the UPF do not have. The control unit _600 realizes various processes in the UPF by reading and executing various programs stored in the storage unit _640 as necessary.

The network connection unit 620 is a functional unit for the UPF to connect to the base station device (gNB) and / or SMF and / or DN in the 5GAN. That is, the UPF transmits / receives user data and / or control information to / from the base station device (gNB) in the 5GAN and / or SMF and / or DN by using the network connection unit 620. You can

Referring to FIG. 2 in detail, the UPF located in the 5GC can communicate with the gNB via the N3 interface and the SMF via the N4 interface by using the network connection_620. Can communicate, can communicate with DN through N6 interface, can communicate with other UPF through N9 interface.

The storage unit_640 is a functional unit for storing programs, user data, control information, etc. necessary for each UPF operation.

UPF functions as an anchor point for intra-RAT mobility or inter-RAT mobility, as an external PDU session point for interconnecting DN (that is, as a gateway between DN and core network, it stores user data). (Forwarding function), packet routing and forwarding function, UL CL (Uplink Classifier) function that supports routing of multiple traffic flows for one DN, and Branching point that supports multi-homed PDU sessions. It has a function, a QoS (Quality of Service) processing function for the user plane, an uplink traffic verification function, a downlink packet buffering function, and a function that triggers downlink data notification (Downlink Data Notification).

Also, UPF may be a gateway for IP communication and / or non-IP communication. The UPF may have a function of transferring IP communication or a function of converting non-IP communication and IP communication. Furthermore, a plurality of gateways may be gateways that connect a single DN to the core network. The UPF may have connectivity with another NF, and may be connected to each device via the other NF.

Note that the user plane is user data that is sent and received between the UE and the network. The user plane may be sent and received using PDU sessions. Further, in the case of 5GS, the user plane may be transmitted / received via the interface between the UE and the NGRAN, and / or the N3 interface, and / or the N9 interface, and / or the N6 interface. Hereinafter, the user plane may be expressed as U-Plane.

Furthermore, the control plane is a control message that is transmitted and received to control the communication of the UE. The control plane may be transmitted and received using a NAS (Non-Access-Stratum) signaling connection between the UE and AMF. Further, in the case of 5GS, the control plane may be transmitted and received using the interface between the UE and the NGRAN and the N2 interface. Hereinafter, the control plane may be expressed as a control plane or a C-Plane.

Furthermore, U-Plane (User Plane; UP) may be a communication path for transmitting and receiving user data, and may be composed of multiple bearers. Further, the C-Plane (Control Plane; CP) may be a communication path for transmitting and receiving control messages, and may be composed of a plurality of bearers.

[2.6. Device configuration]
Next, a device configuration example of the device used in the second embodiment will be described with reference to FIG. The device includes at least two UEs (UE_10 and UE_12), a control unit_700, and a storage unit_730. Each UE (UE_10, UE_12), control unit_700, and storage unit_730 may be connected via a bus.

The control unit_700 is a functional unit that controls the operation / function of the entire device. Note that the control unit_700 may process all the functions that the other devices / function units (UE_10, UE_12, storage unit_730) of the device do not have. The control unit_700 realizes various processes in the device by reading and executing various programs stored in the storage unit_730 as necessary.

Also, the control unit_700 can control communication by the UE_10 and / or UE_12. That is, the control unit_700 can control only UE_10 to communicate, control only UE_12 to communicate, or control UE_10 and UE_12 to communicate.

Also, the controller_700 can control the information exchange between the UE_10 and the UE_12. At this time, the control unit_700 may control the information exchange between the UE_10 and the UE_12 via the storage unit_730. For example, the control unit _700 stores information obtained by the UE_10 executing various procedures in the storage unit _730, and when the UE_12 executes various procedures, the information is stored in the storage unit _730. It can be controlled to utilize the information obtained. Similarly, the control unit _700 stores information obtained by the UE_12 executing various procedures in the storage unit_730, and stores the information in the storage unit_730 when the UE_10 executes various procedures. It is possible to control the use of the provided information. Further, the control unit_700 may perform control so that information exchange between the UE_10 and the UE_12 is directly performed without using the storage unit_730.

The storage unit_730 is a functional unit for storing programs, user data, control information, etc. necessary for each operation of the device. Further, as described above, the storage unit_730 may store information on UE_10 and UE_12.

[3. Explanation of highly specialized terms and identification information used in each embodiment]
Next, highly specialized terms and identification information used in each embodiment will be described in advance.

[3.1. Explanation of highly specialized terms used in each embodiment]
First, terms with high specialization used in each embodiment will be described.

-Network means at least a part of the access network, core network, and DN. Further, one or more devices included in at least a part of the access network, the core network, and the DN may be referred to as a network or a network device. That is, the network performing transmission / reception and / or processing of a message may mean that a device in the network (network device and / or control device) performs transmission / reception and / or processing of a message. .. Conversely, the fact that a device in the network performs transmission / reception of a message and / or processing may mean that the network performs transmission / reception of a message and / or processing.

An SM (session management) message (also referred to as NAS (Non-Access-Stratum) SM message) may be a NAS message used in the procedure for SM, and is sent and received between UE and SMF via AMF. The control message may be Further, the SM message includes a PDU session establishment request message, a PDU session establishment acceptance message, a PDU session completion message, a PDU session rejection message, a PDU session change request message, a PDU session change acceptance message, a PDU session change response message, etc. May be. Further, the procedure for SM may include a PDU session establishment procedure.

Also, the 5GS (5G System) service may be a connection service provided using the core network. Further, the 5GS service may be a service different from the EPS service or the same service as the EPS service.

Also, the non-5GS service may be a service other than the 5GS service, and may include EPS service and / or non-EPS service.

Also, the N1 mode is a mode in which the UE is allowed to access the 5GC via the 5G access network. In other words, the N1 mode may be a mode in which transmission / reception of a message using the N1 interface is executed.

Also, APN (Access Point Name) may be identification information that identifies the core network and / or external networks such as PDN. Furthermore, the APN can also be used as information for selecting a gateway such as PGW / UPF that connects the core network.

In addition, a PDU (Protocol Data Unit or Packet Data Unit) session can be defined as the relationship between the DN that provides the PDU connectivity service and the UE, but it is established between the UE and the external gateway. Connectivity. By establishing a PDU session via the access network and the core network in the 5GS, the UE can transmit / receive user data to / from the DN using the PDU session. Here, this external gateway may be UPF, SCEF, or the like. The UE can perform transmission / reception of user data with a device such as an application server arranged in the DN using the PDU session.

Note that each device (UE, and / or access network device, and / or core network device) may manage one or more pieces of identification information in association with a PDU session. Note that these identification information may include one or more of DNN, TFT, PDU session type, application identification information, NSI identification information, access network identification information, and SSC mode, and other information may be further included. May be included. Further, when a plurality of PDU sessions are established, each piece of identification information associated with the PDU session may have the same content or different content.

Also, the DNN (Data Network Name) may be identification information that identifies the core network and / or an external network such as a DN. Further, the DNN can also be used as information for selecting a gateway such as PGW / UPF that connects the core network. Further, the DNN may correspond to an APN (Access Point Name).

Also, the PDU (Protocol Data Unit or Packet Data Unit) session type indicates the type of PDU session, and there are IPv4, IPv6, Ethernet (registered trademark), and Unstructured. When IPv4 is specified, it indicates that data is sent and received using IPv4. When IPv6 is specified, it indicates that data is sent and received using IPv6. When Ethernet (registered trademark) is designated, it indicates that the Ethernet (registered trademark) frame is transmitted and received. In addition, Ethernet (registered trademark) may indicate that communication using IP is not performed. When Unstructured is specified, it indicates that data is sent and received to the application server etc. in the DN by using Point-to-Point (P2P) tunneling technology. As the P2P tunneling technology, for example, a UDP / IP encapsulation technology may be used. The PDU session type may include IP in addition to the above. The IP can be specified when the UE can use both IPv4 and IPv6. IP may also be expressed as IPv4v6.

A network slice (NS) is a logical network that provides specific network capabilities and characteristics. The UE and / or the network can support a network slice (NW slice; NS) in 5GS.

Also, a network slice instance (NSI) is composed of an instance (entity) of network function (NF) and a set of necessary resources, and forms a network slice to be arranged. Here, the NF is a processing function in the network and is adopted or defined by 3GPP. NSI is an entity of NS consisting of one or more in the core network. Further, the NSI may be configured by a virtual NF (Network Function) generated using NST (Network Slice Template). Here, the NST is a logical expression of one or more NFs, which is associated with a resource request for providing a required communication service or capability. That is, the NSI may be an aggregate in the core network composed of multiple NFs. Further, the NSI may be a logical network configured to divide user data delivered by services or the like. One or more NFs may be configured in NS. The NF configured in the NS may or may not be a device shared with another NS. UE, and / or device in the network, based on NSSAI, and / or S-NSSAI, and / or UE usage type, and / or registration information such as 1 or more NSI ID, and / or APN, and 1 or more. Can be assigned to NS. The UE usage type is a parameter value used for identifying the NSI and included in the registration information of the UE. The UE usage type may be stored in the HSS. AMF may select SMF or UPF based on the UE usage type.

Also, S-NSSAI (Single Network Slice Selection Assistance Information) is information for identifying the NS. The S-NSSAI may be configured with only SST (Slice / Service type), or may be configured with both SST and SD (Slice Differentiator). Here, SST is information indicating the behavior of NS expected in terms of functions and services. Further, SD may be information for interpolating SST when selecting one NSI from a plurality of NSI indicated by SST. The S-NSSAI may be peculiar information for each PLMN, or may be standard information shared by the PLMNs. Further, the network may store one or more S-NSSAIs in the registration information of the UE as the default S-NSSAI. Note that if the S-NSSAI is the default S-NSSAI and the UE does not send a valid S-NSSAI in the registration request message to the network, the network may provide the NS associated with the UE.

NSSAI (Network Slice Selection Assistance Information) is a collection of S-NSSAI. Each S-NSSAI included in NSSAI is information that assists the access network or core network in selecting the NSI. The UE may store the NSSAI permitted from the network for each PLMN. Also, NSSAI may be information used to select the AMF.

In addition, SSC (Session and Service Continuity) mode indicates the mode of session service continuity (Session and Service Continuity) supported by the system and / or each device in the 5G system (5GS). More specifically, it may be a mode indicating the type of session service continuation supported by the PDU session established between the UE and the UPF. Note that the SSC mode may be a mode indicating the type of session service continuation set for each PDU session. Furthermore, the SSC mode may be composed of three modes, SSC mode 1, SSC mode 2, and SSC mode 3. Note that the SSC mode associated with the PDU session does not have to be changed while the PDU session continues.

Also, SSC mode 1 is the mode in which the network maintains the connectivity service provided to the UE. When the PDU session type associated with the PDU session is IPv4 or IPv6, the IP address may be maintained when the session service is continued.

Furthermore, SSC mode 1 may be a session service continuation mode in which the same UPF is maintained regardless of the access technology used when the UE connects to the network. More specifically, SSC mode 1 is a mode that enables session service continuity without changing the UPF used as the PDU session anchor of the established PDU session even if UE mobility occurs. Good.

Also, SSC mode 2 is a mode in which the network releases the connectivity service provided to the UE and the corresponding PDU session. In SSC mode 2, if the PDU session type associated with the PDU session is IPv4, IPv6, or IPv4v6, the IP address assigned to the UE is released when changing the anchor of the PDU session. Good.

Moreover, SSC mode 2 may be a session service continuation mode in which the same UPF is maintained only within the UPF serving area. More specifically, SSC mode 2 may be a mode that realizes session service continuation without changing the UPF used by the established PDU session, as long as the UE is in the serving area of the UPF. Furthermore, SSC mode 2 is a mode that realizes session service continuity by changing the UPF used by an established PDU session when UE mobility occurs, such as when leaving the UPF serving area. Good.

Here, the UPF serving area may be an area where one UPF can provide a session service continuation function, or a subset of an access network such as a RAT or cell used when the UE connects to the network. May be Further, the subset of access networks may be networks comprised of one or more RATs and / or cells.

Note that the change of the anchor point of the PDU session of SSC mode 2 (hereinafter, also referred to as PDU session anchor) may be realized by each device executing the anchor point change procedure of the PDU session of SSC mode 2. The anchor or anchor point may be expressed as an end point.

In addition, SSC mode 3 is a mode in which a change in the user plane is revealed to the UE while the network guarantees that connectivity will not be lost. In the case of SSC mode 3, in order to realize better connectivity service, a PDU session passing through a new PDU session anchor point may be established before the established PDU session is disconnected. Furthermore, in SSC mode 3, when the PDU session type associated with the PDU session is IPv4, IPv6, or IPv4v6, the IP address assigned to the UE is not maintained when changing the anchor of the PDU session. Good.

Furthermore, SSC mode 3 is a PDU session established between the UE and UPF, and / or a new PDU session via a new UPF for the same DN before disconnecting the communication path, and / or Alternatively, it may be a session service continuation mode that permits establishment of a communication path. Furthermore, SSC mode 3 may be a session service continuation mode that allows the UE to be in multihoming. Furthermore, SSC mode 3 may be a mode in which session service continuation using a plurality of PDU sessions and / or UPFs associated with the PDU sessions is permitted. In other words, in SSC mode 3, each device may realize session service continuation using a plurality of PDU sessions, or may realize session service continuation using a plurality of UPFs.

Here, when each device establishes a new PDU session, and / or a communication path, the selection of a new UPF may be performed by the network, and the new UPF is the location where the UE is connected to the network. It may be the most suitable UPF. Furthermore, if multiple PDU sessions and / or UPF used by the PDU sessions are valid, the UE immediately associates the communication of the application and / or flow with the newly established PDU session. Alternatively, it may be performed based on the completion of communication.

Note that the change of the anchor point of the SSC mode3 PDU session may be realized by each device executing the anchor point change procedure of the SSC mode3 PDU session.

Also, the default SSC mode is the SSC mode used by the UE and / or the network when a specific SSC mode is not determined. Specifically, the default SSC mode is the SSC mode used by the UE when there is no SSC mode request from the application and / or when there is no UE policy to determine the SSC mode for the application. Good. Also, the default SSC mode may be the SSC mode used by the network when there is no SSC mode request from the UE.

Note that the default SSC mode may be set for each DN, based on subscriber information, and / or operator policy, and / or UE policy, or may be set for each PDN, or UE. , And / or may be set for each subscriber. Further, the default SSC mode may be information indicating SSC mode 1, SSC mode 2 or SSC mode 3.

Also, the PDU session anchor point change procedure is a procedure for switching the PDU session used for transmitting and receiving user data from the first PDU session to the second PDU session. The anchor point change procedure of the PDU session may include an anchor point change procedure of the PDU session of SSC mode 2 and an anchor point change procedure of the PDU session of SSC mode 3.

Here, the first PDU session may be a PDU session used for user data communication before changing the anchor point of the PDU session. The second PDU session may be a PDU session used for user data communication after changing the anchor point of the PDU session.

The SSC mode2 PDU session anchor point change procedure is a procedure for releasing the first PDU session and then establishing the second PDU session. The anchor point change procedure of the SSC mode 2 PDU session may be a procedure initiated by the network.

Specifically, the anchor point change procedure of the PDU session of SSC mode 2 is that the AMF and / or SMF sends the PDU session release command (PDU session release command) to the UE while the first PDU session is established. ) The UE that has transmitted the message and has received the PDU session release command message may start the PDU session establishment procedure to establish the second PDU session.

Note that the PDU session release command message may include information indicating a change in the anchor point of the PDU session. Further, the information indicating the change of the anchor point of the PDU session may be a reactivation request (reactivation request) which is the 39th 5GSM reason value (5GSM cause # 39).

Further, in the PDU session establishment procedure for establishing the second PDU session, from the UE to AMF, and / or SMF, to transfer the PDU session establishment request message, and / or PDU session establishment request message The NAS message transmitted and received may include a PDU session ID that identifies the first PDU session and a PDU session ID that identifies the second PDU session. Further, the PDU session type, SSC mode, DNN, and S-NSSAI transmitted and received in the PDU session establishment procedure for establishing the second PDU session are the PDU session establishment procedure for establishing the first PDU session. It may be the same as the PDU session type transmitted / received in SSC mode, DNN, and S-NSSAI.

Also, the anchor point change procedure for SSC mode 3 PDU session is a procedure for establishing a second PDU session before releasing the first PDU session. The anchor point change procedure for the SSC mode3 PDU session may be a network-initiated procedure.

Specifically, the anchor point change procedure of the SSC mode 3 PDU session is such that the AMF and / or SMF sends the PDU session change command (PDU session modification command) to the UE while the first PDU session is established. ) A UE that has transmitted the message and has received the PDU session change command message may start the PDU session establishment procedure to establish the second PDU session.

Note that the PDU session change command message may include information indicating a change in the anchor point of the PDU session. Further, the information indicating the change of the anchor point of the PDU session may be a reactivation request (reactivation request) which is the 39th 5GSM reason value (5GSM cause # 39).

Also, the tracking area is a single or multiple range that can be represented by the location information of the UE managed by the core network. The tracking area may be composed of a plurality of cells. Furthermore, the tracking area may be a range where a control message such as paging is broadcast, or a range where the UE can move without performing a handover procedure. Furthermore, the tracking area may be a routing area, a location area, or the like. Hereinafter, the tracking area may be a TA (Tracking Area).

Also, the TA list is a list that includes one or more TAs assigned by the network to the UE. The UE may be able to move without executing the tracking area update procedure while moving in one or a plurality of TAs included in the TA list. In other words, the UE list may be a group of information indicating the areas that the UE can move without executing the tracking area update procedure. The TA list may be expressed as a TAI list composed of one or more TAIs (Tracking area identity), and hereinafter, the TAI list may refer to the TA list.

Also, LADN (Local Area Data Network) is a DN to which a UE can connect only at a specific location and provides connectivity to a specific DNN (that is, LADN DNN).

LADN information is information related to LADN. The LADN information may be information indicating a specific LADN available to the UE. The LADN information may include LADN DNN and LADN service area information. The LADN DNN may be a type of DNN, and may be a DNN used when establishing a PDU session for LADN. Furthermore, the LADN DNN may be information indicating a LADN or information indicating a DN treated as a LADN. Furthermore, the LADN service area information may be information indicating the LADN service area. Furthermore, the LADN service area information may be provided as a set of tracking areas or as a TAI (Tracking area identity) list. The LADN service area may be an area in which a PDU session for LADN can be established or an area in which connection to LADN is possible.

Also, a PDU session for LADN (PDU session for LADN) is a PDU session associated with the DNN associated with the LADN. The PDU session for LADN may be a PDU session established for LADN. In other words, it may be a PDU session established between the UE and the LADN or a PDU session used for user data communication between the UE and the LADN. The PDU session for LADN may be a PDU session that can be established only in the LADN service area.

NB-IoT (Narrowband IoT) is a RAT (Radio Access Technology) with limited bandwidth. The NB-IoT may be a RAT for providing a communication service to an IoT terminal, or a RAT with limited functions. Further, the NB-IoT may be a RAT that constitutes E-UTRAN. Note that the RAT that constitutes the E-UTRAN other than NB-IoT may be WB-E-UTRAN. Furthermore, using NB-IoT, the mode of the UE connected to the core network and / or DN may be expressed as the NB-N1 mode. Conversely, the mode of the UE connected to the core network and / or the DN may be further expressed as a WB-N1 mode by using a RAT other than NB-IoT.

Also, a multi-homed PDU session is a PDU session established by using multiple UPFs connected to a DN. The multi-homed PDU session may be a PDU session established for a single DN or a PDU session established for a different DN. Further, the multi-homed PDU session may be expressed as a multi-homed IPv6 PDU session.

URLLC (Ultra-Reliable and Low Latency Communications) is communication that achieves high reliability and / or low latency. URLLC may be one of the major communication services provided by 5GS. As a function of configuring the URLLC, there may be redundant communication or IP address maintenance. Supporting URLLC may mean supporting redundant communication or supporting IP address maintenance. Further, supporting URLLC may mean that communication of user data using the same IP address can be sustained even when the anchor point of the PDU session is changed. Further, supporting the URLLC may mean supporting a QoS flow associated with 5QI (5G QoS Identifier) for URLLC, and the QoS rule to which the QoS flow is associated may be defined. It may mean to support, or it may mean to support establishment of a PDU session to which the QoS rule is associated.

Also, redundant communication (Redundant Transmission) is communication in which the transmission and reception of user data is redundant. Redundant communication may be one of the technologies for realizing URLLC. Furthermore, redundant communication may be communication with higher reliability than communication using a single user plane tunnel. The user plane tunnel may be a transfer path used for transmitting / receiving user data between the respective devices, or may be a transfer path established on an interface for transmitting / receiving user data.

Here, the redundant communication may include a first type of redundant communication, a second type of redundant communication, and a third type of redundant communication.

The first type of redundant communication is communication in which the transmission and reception of user data is redundant between the UE and the network by using multiple communication paths via different access networks. The UE may implement the first type of redundant communication by using a plurality of IP addresses.

Here, the first type of redundant communication may be realized by a plurality of PDU sessions. In this case, the UE may implement the first type of redundant communication by using a plurality of PDU sessions established via different access networks. In other words, the UE may implement the first type of redundant communication by using a plurality of PDU session IDs.

Also, the first type of redundant communication may be realized by a single PDU session. More specifically, the first type of redundant communication may be realized by a multi-access PDU session. In this case, the UE may implement the first type of redundant communication by using a single PDU session. In other words, the UE may implement the first type of redundant communication by using a single PDU session ID.

The second type of redundant communication is communication in which the transmission and reception of user data is redundant between the UE and the network by using a plurality of communication paths via a single access network. .. The UE may implement the second type of redundant communication by using a plurality of IP addresses.

Here, the second type of redundant communication may be realized by multiple PDU sessions. In this case, the UE may realize the second type of redundant communication by using a plurality of PDU sessions established via a single access network. In other words, the UE may implement the second type of redundant communication by using a plurality of PDU session IDs.

Also, the second type of redundant communication may be realized by a single PDU session. More specifically, the second type of redundant communication may be realized by a multi-homed PDU session. In this case, the UE may implement the second type of redundant communication by using a single PDU session. In other words, the UE may implement the second type of redundant communication by using a single PDU session ID.

The third type of redundant communication is communication in which the transmission and reception of user data is redundant between the access network or core network and the network. The UE may implement the third type of redundant communication by using a single IP address.

Here, the third type of redundant communication may be realized by a single PDU session. In this case, the UE may implement the third type of redundant communication by using a single PDU session. In other words, the UE may implement the third type of redundant communication by using a single PDU session ID.

Also, IP address preservation is a technology that can continue to use the same IP address. When the IP address maintenance is supported, the UE can continue to use the same IP address for communication of user data even when moving outside the TA. In other words, if IP address maintenance is supported, each device may be able to continue to use the same IP address for communicating user data even when the anchor point of the PDU session changes. ..

Also, the first PDU session may be a PDU session established to realize redundant communication. The first PDU session may be the first established PDU session in order to realize redundant communication. In other words, the first PDU session may be a PDU session established before the second PDU session is established in order to realize redundant communication.

Also, the second PDU session may be a PDU session established to realize redundant communication. The second PDU session may be the second PDU session established in order to realize redundant communication. In other words, the second PDU session may be a PDU session established after establishing the first PDU session in order to realize redundant communication.

[3.2. Description of identification information used in each embodiment]
Next, the identification information used in each embodiment will be described.

First, the first identification information is information indicating whether the UE supports URLLC. The first identification information may be information represented by bits forming a 5GMM capability information element indicating the UE capability in 5G. Further, the first identification information may be information indicating that the UE has requested to use the URLLC.

Furthermore, the first identification information may be information indicating whether or not the UE supports redundant communication. The first identification information may be information represented by bits forming a 5GMM capability information element, which indicates the capability of the UE in 5G. Furthermore, the first identification information may be information indicating that the UE has requested the use of redundant communication.

Here, the information indicating the request for use of redundant communication may be the information indicating the request for use of URLLC. Further, the information indicating the request for use of redundant communication may be information that is a combination of one or more pieces of identification information among the second to third identification information. In other words, the UE may indicate a request for use of redundant communication by transmitting to the network information that is a combination of one or more pieces of identification information among the first to third pieces of identification information. The first to third identification information may be transmitted / received as separate identification information, or may be transmitted / received as one identification information.

Furthermore, the first identification information may be information selected and determined based on the UE settings and / or UE states, and / or user policies, and / or application requirements. Furthermore, the first identification information may be information selected and determined based on information held by another UE and / or information associated with another UE.

The second identification information is information indicating the type of group to which the UE belongs. The second identification information may be UE Reliability Group (UERG). More specifically, the second identification information may be information indicating which redundancy group the UE belongs to when performing the redundant communication.

For example, the first UE, in cooperation with the second UE, in the case of realizing redundant communication, the redundancy group to which the first UE belongs, the redundancy different from the redundancy group to which the second UE belongs. It can be a group.

Furthermore, the second identification information may be information selected and determined based on the UE settings and / or UE states, and / or user policies, and / or application requirements. Furthermore, the second identification information may be information selected and determined based on information held by another UE and / or information associated with another UE.

The third identification information is information that identifies another UE. The third identification information may be information that identifies another UE that cooperates in order to realize redundant communication. For example, when the first UE cooperates with the second UE to realize redundant communication, the third identification information may be information that identifies the second UE. Here, the information that identifies another UE may be 5G-GUTI associated with another UE.

Further, the third identification information may be information selected and determined based on the UE setting and / or the UE state, and / or the user policy, and / or the application request. Further, the third identification information may be information selected and determined based on information held by another UE and / or information associated with the other UE.

The eleventh identification information is information indicating whether or not the network supports URLLC. The eleventh identification information may be information represented by bits forming a 5GS network function support information element, which indicates the capability of the network in 5G. Furthermore, the eleventh identification information may be information indicating that the use of the URLLC of the UE is permitted.

Furthermore, the 11th identification information may be information indicating whether or not the network supports redundant communication. Furthermore, the eleventh identification information may be information represented by the bits forming the 5GS network function support information element, which indicates the capability of the network in 5G. Furthermore, the eleventh identification information may be information indicating that the use of the redundant communication of the UE is permitted.

Here, the information indicating that the use of redundant communication is permitted may be the information indicating that the use of URLLC is permitted. Further, the information indicating that the use of the redundant communication is permitted may be information that is a combination of one or more pieces of identification information among the 12th to 15th pieces of identification information. In other words, the network may indicate that the use of the redundant communication is permitted by transmitting to the UE information that is a combination of one or more pieces of identification information among the eleventh to fifteenth pieces of identification information. The eleventh to fifteenth identification information may be transmitted / received as separate identification information or may be transmitted / received as one identification information.

Furthermore, the eleventh identification information may be the first identification information received by the network, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information. The information may be selected or determined based on the information. Furthermore, the eleventh identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

The twelfth identification information is information indicating the type of group to which the UE belongs. The 12th identification information may be UE Reliability Group (UERG). More specifically, the twelfth identification information may be information indicating which redundancy group the UE belongs to when performing redundant communication.

Further, the twelfth identification information is the second identification information received by the network, and / or the capability information of the network, and / or the operator policy, and / or the network status, and / or the registration information of the user. The information may be selected or determined based on the information. Further, the twelfth identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment. Further, the twelfth identification information may be information selected and determined based on information associated with another UE.

Moreover, the 13th identification information is information for identifying another UE. The thirteenth identification information may be information for identifying another UE that cooperates in order to realize redundant communication. For example, when the first UE cooperates with the second UE to realize redundant communication, the thirteenth identification information may be information that identifies the second UE. Here, the information that identifies another UE may be 5G-GUTI associated with another UE.

Furthermore, the thirteenth identification information is received by the network as the third identification information received, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information. The information may be selected or determined based on the information. Furthermore, the thirteenth identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment. Furthermore, the 13th identification information may be information selected and determined based on the information associated with another UE.

Also, the 14th identification information is information indicating a list of DNNs. The 14th identification information may be information indicating a list of DNNs that can be used for redundant communication. More specifically, the fourteenth identification information may be information indicating a list of DNNs that can be used to establish a PDU session for realizing redundant communication. In other words, the UE may be able to establish a PDU session for realizing redundant communication by using the DNN included in the list of DNNs indicated by the 14th identification information.

Further, the 14th identification information is received by the network as the first identification information and / or the capability information of the network, and / or the operator policy, and / or the state of the network, and / or the registration information of the user, etc. The information may be selected or determined based on the information. Further, the 14th identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

Also, the 15th identification information is information indicating a list of S-NSSAI. The fifteenth identification information may be information indicating a list of S-NSSAI that can be used for redundant communication. More specifically, the fifteenth identification information may be information indicating a list of S-NSSAIs that can be used to establish a PDU session for realizing redundant communication. In other words, the UE may be able to establish a PDU session for realizing redundant communication by using the S-NSSAI included in the list of S-NSSAIs indicated by the fifteenth identification information.

Further, the fifteenth identification information may be the first identification information received by the network, and / or the capability information of the network, and / or the operator policy, and / or the state of the network, and / or the registration information of the user. The information may be selected or determined based on the information. Furthermore, the fifteenth identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

The 21st identification information is information indicating whether the UE supports URLLC in the PDU session established by this procedure in each embodiment. The 21st identification information may be information indicating a request for establishing a PDU session supporting URLLC.

The 21st identification information may be information indicating whether or not the UE supports redundant communication in the PDU session established by this procedure in each embodiment. The 21st identification information may be information indicating a request for establishing a PDU session that supports redundant communication.

Further, the 21st identification information may be information indicating that the PDU session established by this procedure in each embodiment is a PDU session for realizing redundant communication. Here, the information indicating that it is a PDU session for realizing redundant communication may be information indicating that it is a PDU session for realizing URLLC communication. Further, the information indicating the PDU session for realizing the redundant communication may be information that is a combination of one or more pieces of identification information among the 22nd to 27th pieces of identification information. In other words, the UE transmits information combining one or more pieces of identification information among the 21st to 27th pieces of identification information to the network, so that the PDU session established in this procedure in each embodiment is redundant. It may indicate that it is a PDU session for realizing communication. The 21st to 27th identification information may be transmitted / received as separate identification information or may be transmitted / received as one identification information.

Further, the 21st identification information, from the 11th to 15th identification information transmitted and received, one or more identification information, and / or UE settings, and / or UE state, and / or user policy, It may be information selected and / or determined based on the request of the application.

The 22nd identification information is information indicating the type of PDU session established by this procedure in each embodiment. The 22nd identification information may be a Redundancy Sequence Number (RSN). More specifically, the 22nd identification information may be information indicating whether the PDU session established by this procedure in each embodiment is the first PDU session or the second PDU session. Good.

Further, the 22nd identification information may be information transmitted and received when the PDU session established by this procedure in each embodiment is a PDU session for realizing redundant communication. In other words, the 22nd identification information may be information transmitted and received when the PDU session established by this procedure in each embodiment is a PDU session for realizing URLLC.

Furthermore, the 22nd identification information, from the 11th to 15th identification information transmitted and received, one or more identification information, and / or UE settings, and / or UE state, and / or user policy, It may be information selected and / or determined based on the request of the application.

The 23rd identification information is information indicating the SSC mode. The 23rd identification information may be information indicating the SSC mode requested by the UE. More specifically, the 23rd identification information may be information indicating the SSC mode that is requested by the UE and is associated with the PDU session established by this procedure in each embodiment. The 23rd identification information may be information indicating SSC mode 1, information indicating SSC mode 2, or information indicating SSC mode 3.

Furthermore, the 23rd identification information, from the 11th to 15th identification information transmitted and received, one or more identification information, and / or UE settings, and / or UE state, and / or user policy, It may be information selected and / or determined based on the request of the application.

The 24th identification information is information indicating the PDU session type. The 24th identification information may be information indicating the PDU session type requested by the UE. More specifically, the 24th identification information may be information indicating the PDU session type requested by the UE and associated with the PDU session established in this procedure in each embodiment. Note that the 24th identification information may be information indicating IPv4, information indicating IPv6, or information indicating IPv4v6. Furthermore, the 24th identification information may be information indicating Unstructured or information indicating Ethernet (registered trademark).

Furthermore, the 24th identification information, from the transmitted and received 11th to 15th identification information, one or more identification information, and / or UE settings, and / or UE status, and / or user policy, It may be information selected and / or determined based on the request of the application.

Also, the 25th identification information is information indicating the DNN. The 25th identification information may be information indicating the DNN requested by the UE. More specifically, the 25th identification information may be information indicating the DNN requested by the UE and associated with the PDU session established by this procedure in each embodiment.

Furthermore, the 25th identification information, from the 11th to 15th identification information transmitted and received, one or more identification information, and / or UE setting, and / or UE state, and / or user policy, It may be information selected and / or determined based on the request of the application.

The 26th identification information is information indicating S-NSSAI. The 26th identification information may be information indicating the S-NSSAI requested by the UE. More specifically, the 26th identification information may be information indicating the S-NSSAI associated with the PDU session established by this procedure in each embodiment, which is requested by the UE.

Furthermore, the 26th identification information, from the transmitted and received 11th to 15th identification information, one or more identification information, and / or UE settings, and / or UE state, and / or user policy, It may be information selected and / or determined based on the request of the application.

The 27th identification information is information indicating the PDU session ID. The 27th identification information may be information indicating a PDU session ID for identifying an established PDU session. In other words, the 27th identification information may be information indicating a PDU session ID different from the PDU session ID for identifying the PDU session established by this procedure in each embodiment. Further, in other words, the 27th identification information may be information indicating a PDU session ID different from the PDU session ID indicated by the 28th identification information.

Further, the 27th identification information may be information indicating a PDU session ID for identifying the PDU session established as the first PDU session. Note that the 27th identification information is a procedure for establishing a second PDU session (hereinafter, also referred to as a PDU session establishing procedure for establishing a second PDU session) by this procedure in each embodiment. In some cases, the identification information may be transmitted and received.

Furthermore, the 27th identification information may be the identification information transmitted and received when this procedure in each embodiment is a procedure executed within the anchor point change procedure of the PDU session of SSC mode 3. Here, the procedure for changing the anchor point of the PDU session of SSC mode 3 is a procedure for changing the anchor point of the second PDU session (hereinafter, PDU session anchor that provides the second PDU session of SSC mode 3). (Also referred to as a change procedure of)).

Furthermore, the 27th identification information, among the 11th to 15th identification information transmitted and received, one or more identification information, and / or UE settings, and / or UE state, and / or user policy, It may be information selected and / or determined based on the request of the application.

The 28th identification information is information indicating the PDU session ID. The 28th identification information may be information indicating a PDU session ID requested by the UE. More specifically, the 28th identification information may be information required by the UE and indicating a PDU session ID for identifying the PDU session established in this procedure in each embodiment. In other words, the 28th identification information may be information indicating a PDU session ID different from the PDU session ID for identifying the already established PDU session. Further, in other words, the 28th identification information may be information indicating a PDU session ID different from the PDU session ID indicated by the 27th identification information.

Further, the 28th identification information may be information indicating a PDU session ID for identifying the PDU session established as the second PDU session. More specifically, the 28th identification information indicates a PDU session ID for identifying the second PDU session when this procedure in each embodiment is a procedure for establishing the second PDU session. It may be information.

Further, the 28th identification information may be information indicating a PDU session ID for identifying the second PDU session in the anchor point change procedure of the PDU session of SSC mode 3. In other words, the 28th identification information may be information indicating a PDU session ID different from the PDU session ID for identifying the first PDU session in the anchor point change procedure of the SSC mode 3 PDU session.

Furthermore, the 28th identification information, among the 11th to 15th identification information transmitted and received, one or more identification information, and / or the 27th identification information, and / or the setting of the UE, and / or the UE. Information and / or user policy, and / or application requirements.

The 29th identification information is information indicating the PDU session ID. The 29th identification information may be information indicating the old PDU session ID. The 29th identification information may be information indicating a PDU session ID for identifying an established PDU session. In other words, the 29th identification information may be information indicating a PDU session ID different from the PDU session ID for identifying the PDU session established by this procedure in each embodiment. Further, in other words, the 29th identification information may be information indicating a PDU session ID different from the PDU session ID indicated by the 28th identification information.

Further, the 29th identification information may be information indicating a PDU session ID for identifying the first PDU session in the anchor point change procedure of the PDU session of SSC mode 3. The 29th identification information may be identification information transmitted and received when the present procedure in each embodiment is a procedure executed within the anchor point change procedure of the PDU session of SSC mode 3.

Further, the 29th identification information, from the 11th to 15th identification information transmitted and received, one or more identification information, and / or UE settings, and / or UE state, and / or user policy, It may be information selected and / or determined based on the request of the application.

The 31st identification information is information indicating whether or not the network supports URLLC in the PDU session established by this procedure in each embodiment. The 31st identification information may be information indicating that a PDU session supporting URLLC is established. Furthermore, the 31st identification information may be information indicating that a request for establishing a PDU session supporting URLLC has been accepted.

Further, the 31st identification information may be information indicating whether or not the network supports redundant communication in the PDU session established by this procedure in each embodiment. Furthermore, the 31st identification information may be information indicating that a PDU session supporting redundant communication is established. Furthermore, the 31st identification information may be information indicating that a request for establishing a PDU session supporting redundant communication has been accepted.

Further, the 31st identification information may be information indicating that the PDU session established by this procedure in each embodiment is a PDU session for realizing redundant communication. Here, the information indicating that it is a PDU session for realizing redundant communication may be information indicating that it is a PDU session for realizing URLLC communication. Further, the information indicating the PDU session for realizing the redundant communication may be information that is a combination of one or more pieces of identification information among the 32nd to 37th pieces of identification information. In other words, the network transmits information combining one or more pieces of identification information among the 31st to 37th pieces of identification information to the UE, so that the PDU session established in this procedure in each embodiment is redundant. It may indicate that it is a PDU session for realizing communication. The 31st to 37th identification information may be transmitted / received as separate identification information or may be transmitted / received as one identification information.

Furthermore, the 31st identification information is the 21st identification information received by the network, and / or the capability information of the network, and / or the operator policy, and / or the state of the network, and / or the registration information of the user. The information may be selected or determined based on the information. Furthermore, the 31st identification information may be information selected and determined based on other identification information selected by the network in this procedure in each embodiment.

The 32nd identification information is information indicating the type of PDU session established by this procedure in each embodiment. The 32nd identification information may be a Redundancy Sequence Number (RSN). More specifically, the 32nd identification information may be information indicating whether the PDU session established by this procedure in each embodiment is the first PDU session or the second PDU session. Good.

Further, the 32nd identification information may be information transmitted and received when the PDU session established by this procedure in each embodiment is a PDU session for realizing redundant communication. In other words, the 32nd identification information may be information transmitted and received when the PDU session established by this procedure in each embodiment is a PDU session for realizing URLLC.

Furthermore, the 32nd identification information is received by the network in the 22nd identification information received, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information. The information may be selected or determined based on the information. Furthermore, the 32nd identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

Also, the 33rd identification information is information indicating the SSC mode. The 33rd identification information may be information indicating the SSC mode selected by the network. More specifically, the 33rd identification information may be information indicating the SSC mode selected by the network and associated with the PDU session established in this procedure in each embodiment. The selected SSC mode may be SSC mode 1, SSC mode 2, or SSC mode 3.

Further, the 33rd identification information is received by the network in the 23rd identification information received, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information. The information may be selected or determined based on the information. Furthermore, the 33rd identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

The 34th identification information is information indicating the PDU session type. The 34th identification information may be information indicating a PDU session type selected by the network. More specifically, the 34th identification information may be information indicating the PDU session type selected by the network and associated with the PDU session established in this procedure in each embodiment. The selected PDU session type may be IPv4, IPv6, or IPv4v6. Furthermore, the selected PDU session type may be Unstructured or Ethernet (registered trademark).

Furthermore, the 34th identification information is received by the network in the 24th identification information received, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information. The information may be selected or determined based on the information. Furthermore, the 34th identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

Also, the 35th identification information is information indicating the DNN. The 35th identification information may be information indicating the DNN selected by the network. More specifically, the 35th identification information may be information indicating the DNN selected by the network and associated with the PDU session established in this procedure in each embodiment.

Furthermore, the 35th identification information is the 25th identification information received by the network, and / or the capability information of the network, and / or the operator policy, and / or the state of the network, and / or the registration information of the user, etc. The information may be selected or determined based on the information. Furthermore, the 35th identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

Also, the 36th identification information is information indicating S-NSSAI. The 36th identification information may be information indicating the S-NSSAI selected by the network. More specifically, the 36th identification information may be information indicating the S-NSSAI selected by the network and associated with the PDU session established in this procedure in each embodiment.

Furthermore, the 36th identification information is received by the network in the 26th identification information received, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information. The information may be selected or determined based on the information. Furthermore, the 36th identification information may be information selected and determined based on other identification information selected by the network in this procedure in each embodiment.

The 37th identification information is information indicating the PDU session ID. The 37th identification information may be information indicating a PDU session ID for identifying an established PDU session. In other words, the 37th identification information may be information indicating a PDU session ID different from the PDU session ID for identifying the PDU session established by this procedure in each embodiment. Further, in other words, the 37th identification information may be information indicating a PDU session ID different from the PDU session ID indicated by the 38th identification information.

Furthermore, the 37th identification information may be information indicating a PDU session ID for identifying the PDU session established as the first PDU session. The thirty-seventh identification information may be the identification information transmitted and received when the present procedure in each embodiment is the procedure for establishing the second PDU session.

Furthermore, the 37th identification information may be the 27th identification information received by the network, and / or the capability information of the network, and / or the operator policy, and / or the state of the network, and / or the registration information of the user. The information may be selected or determined based on the information. Furthermore, the 37th identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

The 38th identification information is information indicating the PDU session ID. The 38th identification information may be information indicating a PDU session ID determined by the network. More specifically, the thirty-eighth identification information may be information indicating a PDU session ID determined by the network and associated with the PDU session established by this procedure in each embodiment. In other words, the 38th identification information may be information indicating a PDU session ID different from the PDU session ID for identifying the already established PDU session. Further, in other words, the 38th identification information may be information indicating a PDU session ID different from the PDU session ID indicated by the 37th identification information.

Further, the 38th identification information may be information indicating a PDU session ID for identifying the PDU session established as the second PDU session. More specifically, the 38th identification information indicates the PDU session ID for identifying the second PDU session when the present procedure in each embodiment is the procedure for establishing the second PDU session. It may be information.

Furthermore, the 38th identification information is the 27th identification information received by the network, and / or the 28th identification information, and / or the 29th identification information, and / or the network capability information, and / or the operator. The information may be selected and determined based on a policy and / or network status, and / or user registration information. Furthermore, the 38th identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

Also, the 40th identification information is a reason value indicating the reason why a part of the request of the UE is not permitted. The 40th identification information may be a 5GSM reason value (5GSM cause).

For example, the 40th identification information may be information indicating that the establishment of the second PDU session is not currently permitted. Specifically, the 40th identification information may be information indicating that establishment of the second PDU session is not currently permitted after completion of this procedure in each embodiment.

Furthermore, the 40th identification information may be information indicating that communication using the PDU session established by this procedure in each embodiment is not currently permitted. Specifically, the 40th identification information may be information indicating that communication using the PDU session associated with the PDU session ID requested by the UE is not currently permitted. In other words, the 40th identification information may be information indicating that communication using the second PDU session is not currently permitted.

Further, the 40th identification information may be information indicating that establishment of the second PDU session is not permitted in the current PLMN, or communication using the second PDU session is permitted. It may be information indicating that there is not.

Further, the 40th identification information may be information indicating that establishment of a second PDU session is not permitted in the area to which the UE currently belongs, or communication using the second PDU session. May be information indicating that is not permitted. The area to which the UE currently belongs may be an area configured by one or more tracking areas.

Further, the 40th identification information is one or more of the 21st to 29th identification information received by the network, and / or the network capability information, and / or the operator policy, and / or the network identification information. The information may be information selected and determined based on the status and / or user registration information. Furthermore, the 40th identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

The 41st identification information is information indicating the value of the back-off timer (hereinafter, also simply referred to as a timer). The 41st identification information may be information indicating a time when establishment of the second PDU session is not permitted. Furthermore, the 41st identification information may be information indicating a time when communication using the PDU session established in this procedure in each embodiment is not permitted. Here, the PDU session established by this procedure in each embodiment may be the second PDU session. Further, the information indicating time may be information indicating a period or information indicating time.

Each device may set the 41st identification information as the value of the backoff timer based on the transmission / reception of the 41st identification information, or may start the backoff timer in which the 41st identification information is set. Good. Furthermore, the UE may start the PDU session establishment procedure for establishing the second PDU session based on the expiration of the backoff timer in which the 41st identification information is set. Furthermore, each device may authenticate that communication using the PDU session established in this procedure in each embodiment is permitted based on the expiration of the backoff timer that sets the 41st identification information, You may make a transition to a state in which communication using the PDU session established by this procedure in each embodiment is possible.

The 51st identification information is a reason value indicating the reason why the UE request is not permitted. The 51st identification information may be a 5GSM reason value (5GSM cause).

For example, the 51st identification information may be information indicating that the establishment of the requested PDU session is not currently permitted.

Specifically, the 51st identification information may be information indicating that the establishment of the PDU session associated with the PDU session ID requested by the UE is not currently permitted. In other words, the 51st identification information may be information indicating that the establishment of the second PDU session is not currently permitted.

Further, the 51st identification information may be information indicating that establishment of the second PDU session is not permitted in the current PLMN. Furthermore, the 51st identification information may be information indicating that establishment of a second PDU session is not permitted in the area to which the UE currently belongs. The area to which the UE currently belongs may be an area configured by one or more tracking areas.

Further, the 51st identification information is one or more of the 21st to 29th identification information received by the network, and / or the network capability information, and / or the operator policy, and / or the network identification information. The information may be information selected and determined based on the status and / or user registration information. Furthermore, the 51st identification information may be information selected and determined based on other identification information selected by the network in this procedure in each embodiment.

The 52nd identification information is information indicating the value of the backoff timer. The 52nd identification information may be information indicating a time when establishment of the second PDU session is not permitted. Further, the information indicating time may be information indicating a period or information indicating time.

Each device may set the 52nd identification information as the value of the backoff timer based on the transmission and reception of the 52nd identification information, or may start the backoff timer in which the 52nd identification information is set. Good. Further, the UE may start the PDU session establishment procedure for establishing the second PDU session based on the expiration of the backoff timer in which the 52nd identification information is set.

The 61st identification information is information indicating the PDU session ID. The 61st identification information may be information indicating a PDU session ID for identifying a PDU session related to this procedure in each embodiment.

For example, the 61st identification information may be information indicating a PDU session ID for identifying the PDU session established as the first PDU session. Furthermore, the 61st identification information may be information indicating a PDU session ID for identifying a PDU session established as a second PDU session.

Note that the network may include information other than the PDU session ID for identifying the PDU session established as the first PDU session in the 61st identification information, or may be established as the second PDU session. Information other than the information indicating the PDU session ID for identifying the PDU session may be included. Specifically, the network may include empty information or dummy information in the 61st identification information.

Further, the 61st identification information is information previously transmitted and received by the network, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information, etc. The information may be selected or determined based on Furthermore, the 61st identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

The 62nd identification information is a reason value indicating the reason why the PDU session needs to be changed. The 62nd identification information may be a 5GSM reason value (5GSM cause).

For example, the 62nd identification information may be information indicating a request for revalidation of a PDU session. Here, the information indicating the request for revalidation of the PDU session may be the information indicating the revalidation request, which is the 39th 5GSM reason value (5GSM cause).

Further, the 62nd identification information may be information indicating that establishment of the second PDU session is permitted. In other words, the 62nd identification information may be information indicating that the establishment of the second PDU session has become possible.

Further, the 62nd identification information may be information indicating that communication using the second PDU session is permitted. In other words, the 62nd identification information may be information indicating that communication using the second PDU session has become possible.

Furthermore, the 62nd identification information is information previously transmitted and received by the network, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information, etc. The information may be selected or determined based on Furthermore, the 62nd identification information may be information selected and determined based on other identification information selected by the network in the present procedure in each embodiment.

[4. First Embodiment]
Next, the first embodiment will be described. Here, the first embodiment is also referred to as the present embodiment.

In this chapter, "Registration procedure" in Chapter 4.1, "PDU session establishment procedure for establishing the first PDU session" in Chapter 4.2, "PDU session establishment procedure for establishing the second PDU session" in Chapter 4.3 , Section 4.4, "Cases in which the PDU session establishment procedure that establishes the second PDU session immediately after the PDU session establishment procedure that establishes the first PDU session is executed" is explained in order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in Section 4.1.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Chapter 4.2, and performs communication using the first PDU session between the UE and the DN. Transition to a state where

After that, each device establishes the second PDU session by executing the PDU session establishment procedure described in Chapter 4.3, and performs communication using the second PDU session between the UE and the DN. Transition to a state where At this time, the UE can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state capable of redundant communication.

Finally, Section 4.4 describes the case where each device is restricted from executing the PDU session establishment procedure that establishes the second PDU session immediately after performing the PDU session establishment procedure described in Chapter 4.2. ..

In the procedure of this embodiment, each device exchanges support information of URLLC, support information of redundant communication, and / or support information of IP address maintenance between the UE and the network in the registration procedure. Good.

Further, in the PDU session establishment procedure, each device may establish a PDU session that supports URLLC between the UE and the network based on the information exchanged in the registration procedure, and supports redundant communication. Established PDU session may be established, or a PDU session that supports IP address maintenance may be established. The PDU session that supports URLLC, the PDU session that supports redundant communication, and the PDU session that supports IP address maintenance may be PDU sessions that can be established only for a specific DN. Here, the specific DN may be, for example, a LADN.

Furthermore, each device may perform user data communication with URLLC support, redundant communication, or IP address maintenance by using the established PDU session. User data communication may be executed.

The contents described in the present embodiment are also applicable when these are configured as different devices (that is, different physical hardware, different logical hardware, or different software).

[4.1. Registration procedure]
First, the registration procedure will be described with reference to FIG. Here, the registration procedure is also referred to as this procedure. The registration procedure is a 5GS procedure. The registration procedure is a procedure for the UE to take the initiative in registering in the access network and / or the core network and / or the DN. If the UE is not registered in the network, the UE can execute this procedure at an arbitrary timing, for example, when the power is turned on. In other words, the UE can start this procedure at any timing in the non-registered state (RM-DEREGISTERED state). Further, each device (especially UE and AMF) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure.

Furthermore, the registration procedure is to update the location registration information of the UE in the network, and / or to notify the state of the UE from the UE to the network on a regular basis, and / or to update certain parameters for the UE in the network. May be the procedure.

UE may start the registration procedure when performing mobility across TAs. In other words, the UE may start the registration procedure when moving to a TA different from the TA shown in the held TA list. Furthermore, the UE may initiate this procedure when the timer it is running has expired. Furthermore, the UE may initiate the registration procedure when the context of each device needs to be updated due to disconnection or invalidation of the PDU session. Furthermore, the UE may initiate the registration procedure if there is a change in capability information and / or preferences regarding the UE's PDU session establishment. Further, the UE may initiate the registration procedure on a regular basis. Further, the UE may start the registration procedure based on the completion of the UE setting update procedure. The UE is not limited to these, and can execute the registration procedure at any timing.

First, the UE starts the registration procedure by transmitting a Registration request message to AMF via 5GAN (S800) (S802) (S804). Specifically, the UE transmits an RRC message including a registration request message to gNB_110 in 5GAN (S800). The registration request message is a NAS message. Further, the RRC message may be a control message transmitted and received between the UE and the 5G AN or the gNB in the 5G AN. Also, NAS messages are processed in the NAS layer, and RRC messages are processed in the RRC layer. The NAS layer is a layer higher than the RRC layer.

Here, the UE, in the registration request message and / or RRC message, it is possible to transmit by including the first identification information, a control message different from these, for example, a layer lower than the RRC layer (for example, It may be included in the control message of the MAC layer, RLC layer, PDCP layer) and transmitted. Here, the content indicated by the first identification information may be as described above. The UE can notify the network of the content of this identification information by transmitting this identification information. This identification information may indicate the request of the UE by being included in these messages.

Further, the UE, by sending an SM message (for example, a PDU session establishment request message) in the registration request message, or by sending an SM message (for example, a PDU session establishment request message) together with the registration request message, The PDU session establishment procedure may be started during the registration procedure.

Upon receiving the RRC message including the registration request message, gNB_110 in 5GAN selects the AMF to which the registration request message is transferred (S802). Note that the gNB_110 in 5GAN can select the AMF based on the information included in the registration request message and / or the RRC message. Here, it is assumed that AMF_210 is selected. The gNB_110 in 5GAN extracts the registration request message from the received RRC message and transfers the registration request message to the selected AMF_210 (S804).

When the AMF_210 receives the registration request message, the AMF_210 can recognize that the UE requests and / or the content of various identification information included in the registration request message.

When AMF_210 receives the registration request message, it can execute the first condition determination. The first condition determination is for determining whether or not the network (or AMF) accepts the UE request. When the first condition determination is true, the AMF starts the procedure of (A) in FIG. 9, whereas when the first condition determination is false, the AMF starts the procedure of (B) in FIG.

Incidentally, the first condition determination is the reception of the registration request message, and / or each identification information included in the registration request message, and / or subscriber information, and / or network capability information, and / or operator policy, and It may be executed based on the state of the network, and / or the registration information of the user, and / or the context held by AMF. For example, the first condition determination may be true if the network grants the UE request, and the first condition determination may be false if the network does not grant the UE request. Further, the network of the UE registration destination, and / or devices in the network, if the function requested by the UE is supported, the first condition determination is true, does not support the function requested by the UE. In this case, the first condition determination may be false. Further, the first condition determination may be true when the transmitted and received identification information is permitted, and the first condition determination may be false when the transmitted and received identification information is not permitted. The condition that determines whether the first condition determination is true or false is not limited to the condition described above.

First, the case where the first condition judgment is true will be explained. In the procedure of (A) of FIG. 9, the AMF_210 can first execute the fourth condition determination. The fourth condition judgment is for judging whether AMF_210 carries out transmission / reception of an SM message with SMF.

Note that the fourth condition determination may be executed based on whether the AMF_210 has received the SM message. Further, the fourth condition determination may be performed based on whether the registration request message includes the SM message. For example, if the AMF_210 receives the SM message, and / or if the registration request message includes the SM message, the fourth condition determination may be true, if the AMF_210 did not receive the SM message, And / or if the registration request message does not include the SM message, the fourth condition determination may be false. The condition that determines whether the fourth condition determination is true or false is not limited to the condition described above.

The AMF_210 selects the SMF when the fourth condition determination is true, and transmits and receives the SM message to and from the selected SMF, whereas when the fourth condition determination is false. , Do not execute them (S806). Here, it is assumed that SMF_220 is selected. Also, even if the fourth condition determination is true, AMF_210 may stop the procedure of (A) of FIG. 9 when it receives an SM message indicating rejection from SMF. At this time, AMF_210 can start the procedure of (B) of FIG.

Note that the AMF_210 can notify the SMF_220 of the identification information received in the registration request message when transmitting / receiving the SM message to / from the SMF_220 in S806. The SMF_220 can acquire the identification information received from the AMF_210 by transmitting / receiving the SM message to / from the AMF.

Next, the AMF_210 receives the registration request message and / or based on the completion of the transmission / reception of the SM message with the SMF_220, as a response message to the registration request message, via gNB_110, the registration acceptance (Registration accept) to the UE. ) Send the message (S808). For example, when the fourth condition determination is true, AMF_210 may transmit the registration acceptance message based on the reception of the registration request message from the UE. Further, when the fourth condition determination is false, the AMF_210 may send the registration acceptance message based on the completion of the transmission / reception of the SM message with the SMF_220. The registration acceptance message is a NAS message transmitted / received on the N1 interface, but is transmitted / received between the UE and gNB_110 by being included in the RRC message.

AMF_210 may include at least one of the 11th, 14th, and 15th identification information in the registration acceptance message and transmit it. Here, the contents indicated by the eleventh, fourteenth, and fifteenth identification information may be as described above. AMF_210 can notify the content of the identification information to the UE by transmitting at least one of the identification information. In addition, AMF_210 may indicate that the network supports each function by transmitting these pieces of identification information, or may indicate that the request of the UE has been accepted. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

Also, AMF_210, regarding which identification information to include in the registration acceptance message, each received identification information, and / or subscriber information, and / or network capability information, and / or operator policy, and / or network status. , And / or the registered information of the user, and / or the context held by AMF_210, and the like, and may be selected and determined.

Further, the AMF_210 can include an SM message (for example, a PDU session establishment acceptance message) in the registration acceptance message or can send an SM message (for example, a PDU session establishment acceptance message) together with the registration acceptance message. However, this transmission method may be executed when the SM message (for example, the PDU session establishment request message) is included in the registration request message and the fourth condition determination is true. Further, this transmission method may be executed when the SM message (for example, the PDU session establishment request message) is included together with the registration request message, and the fourth condition determination is true. By performing such a transmission method, the AMF can show that the procedure for the SM has been accepted in the registration procedure.

Further, the AMF_210, the received identification information, and / or subscriber information, and / or network capability information, and / or operator policy, and / or network status, and / or user registration information, and / or It may be possible to indicate that the request of the UE has been accepted by transmitting a registration acceptance message based on the context or the like held by the AMF.

Further, the AMF_210 may transmit the registration acceptance message by including information indicating that some requests of the UE have been rejected, or transmitting information indicating that some requests of the UE have been rejected. By doing so, the reason why some of the requests of the UE are rejected may be indicated. Furthermore, the UE may recognize the reason why some of the requests of the UE are rejected by receiving the information indicating that some of the requests of the UE have been rejected. The rejection reason may be information indicating that the content indicated by the identification information received by AMF_210 is not permitted.

UE receives the registration acceptance message via gNB_110 (S808). Upon receiving the registration acceptance message, the UE can recognize that the UE request by the registration request message has been accepted and / or the content of each piece of identification information included in the registration acceptance message.

UE can further send a registration completion message to AMF_210 via gNB_110 as a response message to the registration acceptance message (S810). When the UE receives the SM message such as the PDU session establishment acceptance message, the registration completion message may include the SM message such as the PDU session establishment completion message, or may include the SM message. , May indicate that the procedure for SM has been completed. Here, the registration completion message is a NAS message transmitted / received on the N1 interface, but is transmitted / received between the UE and the gNB included in the RRC message.

AMF_210 receives the registration completion message via gNB_110 (S810). Further, each device completes the procedure of (A) of FIG. 9 based on the transmission and reception of the registration acceptance message and / or the registration completion message.

Next, the case where the first condition judgment is false will be explained. In the procedure of (B) of FIG. 9, the AMF_210 transmits a registration reject message to the UE via the gNB_110 as a response message to the registration request message (S812). Here, the registration rejection message is a NAS message transmitted / received on the N1 interface, but is transmitted / received between the UE and gNB_110 by being included in the RRC message.

Note that AMF_210 may indicate that the request of the UE by the registration request message has been rejected by transmitting the registration refusal message. Further, the AMF_210 may include the information indicating the reason for rejection in the registration refusal message, and may indicate the reason for refusal by transmitting the reason for refusal. Furthermore, the UE may recognize the reason why the UE's request was rejected by receiving information indicating why the UE's request was rejected. The reason for rejection may be information indicating that the content indicated by the identification information received by AMF is not permitted.

UE receives the registration refusal message via gNB_110 (S812). By receiving the registration refusal message, the UE can recognize that the request of the UE by the registration request message is rejected and the contents of various identification information included in the registration refusal message. Further, the UE may recognize that the request from the UE has been rejected if the UE does not receive the registration refusal message even after a lapse of a predetermined period after transmitting the registration request message. Each device completes the procedure (B) in this procedure based on the transmission and reception of the registration refusal message.

Note that the procedure of FIG. 9 (B) may be started when the procedure of FIG. 9 (A) is stopped. In the procedure of (A) of FIG. 9, when the fourth condition determination is true, the AMF_210 may include an SM message, which means rejection such as a PDU session establishment rejection message, in the registration rejection message and may transmit it. , It may indicate that the procedure for SM has been rejected by including an SM message meaning rejection. In that case, the UE may further receive an SM message meaning rejection such as a PDU session establishment rejection message, or may recognize that the procedure for SM has been rejected.

Each device completes the registration procedure based on the completion of the procedure in (A) or (B) of FIG. Note that each device may transition to the state (RM_REGISTERED state) in which the UE is registered in the network based on the completion of the procedure of (A) of FIG. 9, or the completion of the procedure of (B) of FIG. 9. Based on the above, the UE may maintain a state (RM_DEREGISTERED state) in which it is not registered in the network, or may transit to a state in which the UE is not registered in the network. Moreover, the transition of each device to each state may be performed based on the completion of the registration procedure or may be performed based on the establishment of the PDU session.

Further, each device may perform processing based on the information transmitted and received in the registration procedure based on the completion of the registration procedure. For example, when the information indicating that some of the requests of the UE are rejected is transmitted and received, the reason why the request of the UE is rejected may be recognized. Furthermore, each device may perform this procedure again based on the reason why the UE request is rejected, or may perform the registration procedure for the core network or another cell.

Further, the UE may store the identification information received together with the registration acceptance message and / or the registration refusal message based on the completion of the registration procedure, or may recognize the decision of the network.

[4.2. PDU session establishment procedure for establishing the first PDU session]
Next, an outline of a PDU session establishment procedure to establish a PDU session for a DN will be described with reference to FIG. Here, this PDU session establishment procedure is also referred to as this procedure. The PDU session establishment procedure is a procedure in 5GS. The PDU session establishment procedure is a procedure for each device to establish a PDU session. It should be noted that each device can start the PDU session establishment procedure at any timing when the registration procedure is completed and the device is in the registered state. Also, each device may be able to perform the PDU session establishment procedure during the registration procedure. Further, each device may establish a PDU session based on the completion of the PDU session establishment procedure. The PDU session establishment procedure may be a procedure initiated by the UE or may be a procedure initiated and requested by the UE. Each device may establish multiple PDU sessions by executing the PDU session establishment procedure multiple times.

Furthermore, the UE may start the PDU session establishment procedure based on the identification information received in the registration procedure. For example, the UE may initiate a PDU session establishment procedure to establish a PDU session that supports URLLC if URLLC is supported. Further, the UE may initiate a PDU session establishment procedure to establish a PDU session supporting redundant communication, if redundant communication is supported. Further, the UE may initiate a PDU session establishment procedure to establish a PDU session supporting IP address maintenance if IP address maintenance is supported.

First, the UE sends a NAS message including a PDU session establishment request (PDU session establishment request) message to the SMF_220 via 5GAN and AMF_210 (S900) (S902) (S904) to perform the PDU session establishment procedure. Start.

Specifically, the UE transmits a NAS message including a PDU session establishment request message to AMF_210 via gNB_110 in 5GAN via the N1 interface (S900).

Here, the UE, the PDU session establishment request message and / or NAS message, 21 to 23, can be transmitted including at least one of the 28 identification information, a control message different from these, For example, it may be included in a control message of a layer lower than the NAS layer (for example, RRC layer, MAC layer, RLC layer, PDCP layer) and transmitted. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st to 23rd and 28th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 22nd identification information indicates that the first PDU session is established. It is preferable to indicate that it is a PDU session, and the SSC mode indicated by the 23rd identification information is preferably SSC mode 1. Note that the SSC mode indicated by the 23rd identification information is not excluded from being SSC mode 2 and SSC mode 3. The UE can notify the network of the contents of these pieces of identification information by transmitting these pieces of identification information. Moreover, these identification information may indicate the request of the UE by being included in these messages. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

When AMF_210 receives the NAS message including the PDU session establishment request message (S900), it extracts the PDU session establishment request message from the NAS message and selects SMF as the transfer destination of the PDU session establishment request message (S902). Incidentally, AMF_210 is each identification information contained in the PDU session establishment request message and / or NAS message, and / or subscriber information, and / or network capability information, and / or operator policy, and / or network status, The transfer destination SMF may be selected based on the registration information of the user and / or the context held by the AMF and / or the like. Here, it is assumed that SMF_220 is selected.

-AMF_210 transfers the PDU session establishment request message to the selected SMF_220 via the N11 interface (S904).

Upon receiving the PDU session establishment request message, SMF_220 can recognize that the UE is requesting and / or various identification information included in the PDU session establishment request message. The SMF_220 then executes the third condition determination. The third condition determination is for the SMF_220 to determine whether to accept the UE request. In the third condition determination, the SMF_220 determines whether the third condition determination is true or false. The SMF_220 starts the procedure of (A) of FIG. 10 when the third condition determination is true, and starts the procedure of (B) of FIG. 10 when the third condition determination is false.

The third condition determination is a PDU session establishment request message, and / or each identification information included in the PDU session establishment request message, and / or subscriber information, and / or network capability information, and / or operator policy. , And / or network status, and / or user registration information, and / or context held by SMF_220. For example, if the network permits the UE request, the third condition determination may be true. If the network does not permit the UE request, the third condition determination may be false. Furthermore, if the network to which the UE is connected, and / or the device in the network supports the function requested by the UE, the third condition determination may be true and does not support the function requested by the UE. In this case, the third condition determination may be false. Further, the third condition determination may be true when the transmitted and received identification information is permitted, and the third condition determination may be false when the transmitted and received identification information is not permitted. The condition that determines the truth of the third condition determination is not limited to the above-mentioned condition.

Next, the steps when the third condition judgment is true, that is, the steps of the procedure in (A) of FIG. 10 will be described. The SMF_220 selects the UPF of the establishment destination of the PDU session, transmits a session establishment request message to the selected UPF via the N4 interface (S906), and starts the procedure of (A) of FIG. Here, it is assumed that UPF_230 is selected.

Here, SMF_220, each identification information acquired based on the reception of the PDU session establishment request message, and / or subscriber information, and / or network capability information, and / or operator policy, and / or network status, One or more UPFs may be selected based on the registration information of the user and / or the context held by the SMF_220. When a plurality of UPFs are selected, SMF_220 may send a session establishment request message to each UPF.

UPF_230 receives the session establishment request message from SMF_220 via the N4 interface (S906), and creates a context for the PDU session. Further, the UPF_230 receives the session establishment request message and / or transmits the session establishment response message to the SMF_220 via the N4 interface based on the creation of the context for the PDU session (S908).

SMF_220 receives the session establishment response message from UPF_230 via the N4 interface as a response message to the session establishment request message (S908). The SMF_220 may perform the address assignment of the address assigned to 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 session establishment response message.

SMF_220 is based on the reception of the PDU session establishment request message, and / or the selection of UPF, and / or the reception of the session establishment response message, and / or the completion of the address assignment of the address assigned to the UE, via AMF_210, the UE Sends a PDU session establishment acceptance message to (S910) (S912).

Specifically, the SMF_220 transmits a PDU session establishment acceptance message to the AMF_210 via the N11 interface (S910), and the AMF_210 that has received this transmits the PDU session to the UE via the gNB_110 via the N1 interface. A NAS message including the establishment acceptance message is transmitted (S912). The PDU session establishment acceptance message is a NAS message and may be a response message to the PDU session establishment request. In addition, the PDU session establishment acceptance message can indicate that the establishment of the PDU session has been accepted. Further, the NAS message may be a downlink NAS transport (DL NAS transport) message.

Here, SMF_220 and / or AMF_210 may indicate that the request of the UE by the PDU session establishment request has been accepted by transmitting the PDU session establishment acceptance message.

-SMF_220 and / or AMF_210 may include at least one of the 31st to 33rd and 38th identification information in the PDU session establishment acceptance message and may transmit it. Here, the contents indicated by the 31st to 33rd and 38th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 32nd identification information is the first PDU session to be established. It is preferable that the PDU session is SPDU mode, and that the SSC mode indicated by the 33rd identification information is SSC mode 1. Also, the PDU session ID indicated by the 38th identification information may be the same as or different from the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. SMF_220 and / or AMF_210 can notify the content of these pieces of identification information to the UE by transmitting at least one of these pieces of identification information.

Note that the SMF_220 and / or the AMF_210 may indicate that the network supports each function or may indicate that the request of the UE is accepted by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

Incidentally, SMF_220 and / or AMF_210, which identification information to include in the PDU session establishment acceptance message, each identification information received, and / or subscriber information, and / or network capability information, and / or operator policy, It may be selected and determined based on the state of the network, and / or the registration information of the user, and / or the context held by AMF.

Also, SMF_220 and / or AMF_210 can include the selected and / or permitted PDU session ID in the PDU session establishment acceptance message. In addition, SMF_220 and / or AMF_210 can specify a PDU session type indicating the type of the selected and / or permitted PDU session. As described above, any one of IPv4, IPv6, IP, Ethernet (registered trademark), and Unstructured can be designated as the PDU session type. In addition, the SMF_220 and / or the AMF_210 can include the SSC mode of the selected and / or permitted PDU session in the PDU session establishment acceptance message.

Furthermore, SMF_220 and AMF_210 can include the approved QoS rules in the PDU session establishment acceptance message. It should be noted that the approved QoS rule group may include one or more QoS rules. Further, in this procedure, when a plurality of QoS flows and / or user plane radio bearers are established, the approved QoS rule group may include a plurality of QoS rules. On the contrary, when only one QoS flow and / or user plane radio bearer is established in this procedure, one QoS rule may be included in the approved QoS rule group.

Further, SMF_220 may be transmitted in the PDU session establishment acceptance message including information indicating that some requests of the UE have been rejected, or information indicating that some requests of the UE have been rejected. May indicate why some of the UE's requests were rejected. Furthermore, the UE may recognize the reason why some of the requests of the UE are rejected by receiving the information indicating that some of the requests of the UE have been rejected. The rejection reason may be information indicating that the content indicated by the identification information received by the SMF_220 is not permitted.

UE receives the NAS message including the PDU session establishment acceptance message from AMF_210 via the N1 interface (S912). By receiving the PDU session establishment acceptance message, the UE can recognize that the UE request by the PDU session establishment request has been accepted, and / or the content of each identification information included in the PDU session establishment acceptance message. ..

Next, the UE sends a PDU session establishment completion message to SMF_220 via AMF_210 (S914) (S916). Specifically, the UE transmits a PDU session establishment completion message to AMF_210 via the N1 interface (S914). Upon receiving the PDU session establishment completion message from the UE, the AMF_210 transmits the PDU session establishment completion message to the SMF_220 via the N11 interface (S916).

The PDU session establishment completion message transmitted by AMF_210 to SMF_220 may be a response message to the PDU session establishment acceptance message transmitted from SMF_220 to AMF_210 in S910. Further, the PDU session establishment completion message may be a NAS message. Further, the PDU session establishment completion message may be a message indicating that the PDU session establishment procedure is completed.

When SMF_220 receives the PDU session establishment completion message from AMF_210 via the N11 interface (S916), it can execute the second condition determination. The second condition determination is to determine the type of message transmitted and received on the N4 interface. When the second condition determination is true, the SMF_220 transmits a session change request message to the UPF_230 via the N4 interface (S918), and receives a session change accept message transmitted from the UPF_230 as a response message (S918). S920). When the second condition determination is false, the SMF_220 transmits a session establishment request message to the UPF_230 via the N4 interface (S918), and receives the session change accept message transmitted from the UPF_230 as a response message (S918). S920).

Note that the second condition determination may be performed based on whether or not a session on the N4 interface for the PDU session is established. For example, the second condition determination may be true if the session on the N4 interface for the PDU session is established, and the second condition determination may be true if the session on the N4 interface for the PDU session is not established. The condition determination of may be false. The condition that determines the authenticity of the second condition determination is not limited to the condition described above.

Each device completes the procedure of (A) of FIG. 10 based on the transmission / reception of the PDU session establishment completion message, the session change response message, and / or the session establishment response message. When the procedure of (A) of FIG. 10 is completed, the UE is in the state where the PDU session for the DN is established.

Next, each step of the procedure of FIG. 10 (B) will be explained. The SMF_220 transmits a PDU session establishment rejection message to the UE via the AMF_210 (S922) (S924). Specifically, SMF_220 transmits a PDU session establishment rejection message to AMF_210 via the N11 interface (S922). When the AMF_210 receives the PDU session establishment request message from the SMF_220 via the N11 interface (S922), the AMF_210 transmits the PDU session establishment rejection message to the UE using the N1 interface (S924).

Note that the PDU session establishment rejection message may be a NAS message. Further, the PDU session establishment rejection message may be a message indicating that the establishment of the PDU session has been rejected.

Here, the SMF_220 may indicate that the request of the UE by the PDU session establishment request has been rejected by transmitting the PDU session establishment rejection message. Furthermore, the SMF_220 may include the information indicating the reason for rejection in the PDU session establishment rejection message, and may indicate the reason for rejection by transmitting the reason for rejection. Furthermore, the UE may recognize the reason why the UE's request was rejected by receiving information indicating why the UE's request was rejected. Note that the reason for rejection may be information indicating that the content indicated by the identification information received by the SMF is not permitted.

By receiving the PDU session establishment refusal message, the UE can recognize that the UE request by the PDU session establishment request is rejected and the contents of various identification information included in the PDU session establishment refusal message.

Each device completes the PDU session establishment procedure based on the completion of the procedure of (A) or (B) of FIG. It should be noted that each device may transit to a state in which a PDU session is established based on the completion of the procedure of (A) in FIG. It may recognize that the session establishment procedure has been rejected, or may transit to a state in which the PDU session has not been established. Further, the UE is able to communicate with the DN using the established PDU session when the procedure of (A) of FIG. 10 is completed.

Further, each device may perform processing based on the information transmitted and received in the PDU session establishment procedure based on the completion of the PDU session establishment procedure. For example, each device may recognize the reason why the request of the UE is rejected when transmitting / receiving the information indicating that some of the requests of the UE have been rejected. Furthermore, each device may perform this procedure again based on the reason why the UE request is rejected, or may perform the PDU session establishment procedure for another cell.

Further, the UE may store the identification information received together with the PDU session establishment acceptance message and / or the PDU session establishment rejection message based on the completion of the PDU session establishment procedure, or recognize the decision of the network. Good.

[4.3. PDU session establishment procedure for establishing the second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in section 4.2, but it is necessary to replace gNB_110 with gNB_112, replace SMF_220 with SMF_222, and replace UPF_230 with UPF_232. Also, the identification information included in the PDU session establishment request message and / or the NAS message and the identification information included in the PDU session establishment acceptance message differ from those in Section 4.2. However, since there are many points in common with the explanation in Chapter 4.2, explanations of common points are omitted, and in the following, different points will be mainly described. The UE, AMF and DN are the same as in Chapter 4.2.

First, the UE starts a PDU session establishment procedure by transmitting a NAS message containing a PDU session establishment request message to the SMF_222 via 5GAN and AMF_210 (S900) (S902) (S904). , GNB_110 instead of gNB_110, the NAS message including the PDU session establishment request message is transmitted (S900).

Here, the UE, the PDU session establishment request message and / or NAS message, 21 to 23, can be transmitted including at least one of the 28 identification information, a control message different from these, For example, it may be included in a control message of a layer lower than the NAS layer (for example, RRC layer, MAC layer, RLC layer, PDCP layer) and transmitted. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st to 23rd and 28th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 22nd identification information indicates that the second PDU session is established. It is preferable to indicate that it is a PDU session, and the SSC mode indicated by the 23rd identification information is preferably SSC mode 1.

Further, the PDU session ID indicated by the 28th identification information is preferably different from the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message in Chapter 4.2, and the PDU session in Chapter 4.2. It is preferably different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message.

The UE can notify the network of the contents of these identification information by transmitting these identification information. These pieces of identification information may indicate the request of the UE by being included in these messages. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Incidentally, gNB_112, when receiving the PDU session establishment request message from the UE, may be transferred directly to AMF_210 via the N2 interface, or transferred to gNB_110 via the Xn interface, gNB_110 is AMF_210 via the N2 interface. May be forwarded to. Note that gNB_112 transfers the PDU session establishment request message to gNB_110 via the Xn interface, and gNB_110 transfers to AMF_210 via the N2 interface because the N2 interface between gNB_112 and AMF_210 for that UE is not set. May be the case. Further, the gNB_112 may directly transfer the PDU session establishment request message to the AMF_210 via the N2 interface when the N2 interface between the gNB_112 and the AMF_210 for the UE is set.

Also, when the AMF_210 receives the PDU session establishment request message, it selects SMF_222 as the transfer destination (S902) and transfers the PDU session establishment request message to the SMF_222 via the N11 interface (S904).

Further, when the SMF_222 receives the PDU session establishment request message from the AMF_210 (S904), the SMF_222 can recognize that the UE is requesting and various identification information included in the PDU session establishment request message.

Also, SMF_222 selects UPF_232 as the UPF of the establishment destination of the PDU session, and sends a session establishment request message to UPF_232 via the N4 interface (S906).

Upon receiving the session establishment request message from SMF_222, UPF_232 creates a context for the PDU session and sends a session establishment response message to SMF_222 via the N4 interface (S908).

When SMF_222 receives the session establishment response message from UPF_232, SMF_222 may allocate the address of the address to be assigned to the UE. The SMF_222 transmits a PDU session establishment acceptance message to the UE via the AMF_210 (S910) (S912). Specifically, the SMF_222 transmits a PDU session establishment acceptance message to the AMF_210 via the N11 interface (S910), and the AMF_210 having received this includes the PDU session establishment acceptance message to the UE via the N1 interface. Send a NAS message (S912). At this time, when gNB_112 has directly transmitted the PDU session establishment request message to AMF_210, AMF_210 may directly transmit the PDU session establishment acceptance message to gNB_112. Further, when the gNB_112 has transmitted the PDU session establishment request message to the AMF_210 via the gNB_110, the AMF_210 may transmit the PDU session establishment acceptance message to the gNB_112 via the gNB_110. The gNB_112 sends a NAS message including a PDU session establishment acceptance message to the UE.

Here, the NAS message may be a downlink NAS transport (DL NAS transport) message. Furthermore, SMF_222 and / or AMF_210 may include at least one of the 31st to 33rd and 38th identification information in the PDU session establishment acceptance message, and may transmit the message. Here, the contents indicated by the 31st to 33rd and 38th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 32nd identification information indicates that the second PDU session is established. It is preferable that the PDU session is SPDU mode, and that the SSC mode indicated by the 33rd identification information is SSC mode 1. Further, the PDU session ID indicated by the 38th identification information is preferably different from the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of Chapter 4.2, and the PDU session of Chapter 4.2. It is preferable that it is different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message, and the same as the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Is preferred, but may be different. The SMF_222 and / or the AMF_210 can notify the UE of the content of the identification information by transmitting the identification information. Note that the SMF_222 and / or the AMF_210 may indicate that the network supports each function or may indicate that the request from the UE has been accepted, by transmitting the identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

Also, the UE, by receiving the PDU session establishment acceptance message, that the request of the UE by the PDU session establishment request is accepted, and / or recognize the content of each identification information included in the PDU session establishment acceptance message. You can

The above is the difference between this procedure and the procedure in Section 4.2. For the parts not described in this chapter, the description in Chapter 4.2 can be applied.

When this procedure is completed, each device may be in a state where a second PDU session for the same DN as the already established DN for the first PDU session is established.

By using the second PDU session established as described above together with the first PDU session, the UE can perform redundant communication.

[4.4. A case where the PDU session establishment procedure for establishing the second PDU session is immediately executed after the PDU session establishment procedure for establishing the first PDU session is executed]
Each device establishes the first PDU session by executing the procedure in Section 4.2, and immediately after that, establishes the second PDU session by executing the procedure in Section 4.3 and performs redundant communication. It can be carried out. However, in some cases, such as when the device is congested, each device may not be able to immediately establish the second PDU session after establishing the first PDU session. In this chapter, such cases are explained by dividing them into four cases.

[4.4.1. Case 1]
Case 1 is a case where the establishment of the second PDU session is restricted in the PDU session establishment procedure in Chapter 4.2 executed to establish the first PDU session.

Specifically, the UE sends a PDU session establishment request message to the SMF_220 in the PDU session establishment procedure in section 4.2, and the SMF_220 establishes a PDU session establishment including at least one of the 40th to 41st identification information. This is a case where the establishment of the second PDU session is restricted by receiving the acceptance message.

Here, the contents indicated by the 40th identification information and the 41st identification information may be as described above.

That is, the UE, in the PDU session establishment procedure of Chapter 4.2, if the PDU session establishment acceptance message including at least one of the 40th to 41st identification information is received, the period indicated by the 41st identification information elapses. Until (timer expires) the PDU session establishment procedure in section 4.3 cannot be performed. Then, the UE becomes able to execute the PDU session establishment procedure in section 4.3 after the period indicated by the 41st identification information has elapsed (the timer has expired). In other words, the UE that received the timer value contained in the PDU session establishment acceptance message in section 4.2 sets its timer value as a timer that limits the execution of the PDU session establishment procedure in section 4.3, and the UE has set it. After the timer expires, the procedure for establishing a second PDU session (the PDU session establishment procedure in section 4.3) can be started.

[4.4.2. Case 2]
Case 2, like Case 1, is a case where the establishment of the second PDU session is restricted in the PDU session establishment procedure of Section 4.2 executed to establish the first PDU session.

That is, the UE, in the PDU session establishment procedure of Chapter 4.2, if the PDU session establishment acceptance message including at least one of the 40th to 41st identification information is received, the period indicated by the 41st identification information elapses. Until (timer expires) the PDU session establishment procedure in section 4.3 cannot be performed. Up to this point, it is similar to Case 1.

However, after the PDU session establishment procedure in section 4.2 is completed and before the period indicated by the 41st identification information elapses (timer expires), the UE sends the PDU session change command message from the core network side. Can be set to execute the PDU session establishment procedure in section 4.3 before the period indicated by the 41st identification information expires (timer expires), or the period indicated by the 41st identification information. It can also be set to extend or shorten (the period during which the PDU session establishment procedure in section 4.3 cannot be performed).

In addition, after the PDU session establishment procedure in Chapter 4.2 is completed, the UE is performing the PDU session establishment procedure in Chapter 4.3 even after the period indicated by the 41st identification information has elapsed (timer has expired). When not present, the PDU session change command message may be sent from the core network side to reset the period indicated by the 41st identification information (the period during which the PDU session establishment procedure in Chapter 4.3 cannot be executed).

Furthermore, when the UE receives the PDU session establishment acceptance message including at least the 40th identification information in the PDU session establishment procedure in Section 4.2, by transmitting the PDU session change command message from the core network side, The PDU session establishment procedure can be set to be executable, or the PDU session establishment procedure in section 4.3 can be started. In this case, the PDU session establishment acceptance message may not include the 41st identification information.

Specifically, the UE receives the PDU session change command message including at least one of the identification information from 61st to 62nd from the SMF_220 after completing the PDU session establishment procedure in Chapter 4.2, The timing to start the procedure for establishing the second PDU session can be changed.

Here, the contents indicated by the 61st identification information and the 62nd identification information may be as described above.

The 61st identification information is information indicating a PDU session ID for identifying the PDU session established as the first PDU session, or a PDU for identifying the PDU session established as the second PDU session. It is preferably information indicating a session ID or information indicating null (null).

Further, when the 61st identification information is information indicating a PDU session ID for identifying the PDU session established as the first PDU session, the 62nd identification information is the information of the second PDU session. Information indicating that establishment is now permitted, and / or information indicating that a second PDU session can be established, and / or communication using a second PDU session is permitted. It may be information indicating that such a situation has occurred and / or information indicating that communication using the second PDU session has become possible.

If the 61st identification information is information indicating a PDU session ID for identifying the PDU session established as the second PDU session, the 62nd identification information indicates the PDU session of the second PDU session. Information indicating that establishment is now permitted, and / or information indicating that a second PDU session can be established, and / or communication using a second PDU session is permitted. It may be information indicating that such a situation has occurred and / or information indicating that communication using the second PDU session has become possible.

If the 61st identification information is the information indicating the PDU session ID for identifying the PDU session established as the second PDU session, the 62nd identification information is the revalidation of the PDU session. May be the information indicating the request, specifically, the 39th 5GSM reason value (5GSM cause) or the information indicating the reactivation request.

If the 61st identification information is information indicating empty (null), the 62nd identification information is information indicating that establishment of the second PDU session is permitted, and / Or information indicating that the second PDU session can be established, and / or information indicating that communication using the second PDU session is permitted, and / or the second The information may be information indicating that communication using the PDU session has become possible.

Further, when the 61st identification information is information indicating empty (null), the 62nd identification information may be information indicating a request for revalidation of the PDU session, and specifically, The 39th 5GSM reason value (5GSM cause) may be used, or the information indicating a reactivation request may be used.

Note that null may be indicated by not including the 61st identification information in the PDU session change command message. That is, when the 61st identification information is not included in the PDU session change command message, the 62nd identification information is information indicating that establishment of the second PDU session is permitted, and / or 2 Information indicating that the establishment of the second PDU session is possible, and / or information indicating that communication using the second PDU session is permitted, and / or the second PDU session It may be information indicating that the communication used is enabled.

Further, when the 61st identification information is not included in the PDU session change command message, the 62nd identification information may be information indicating a request for revalidation of the PDU session, and specifically, the 39th identification information. It may be the 5GSM reason value (5GSM cause) or information indicating a reactivation request.

Also, the PDU session change command message may include the 41st identification information. When the 41st identification information is included in the PDU session change command message, the 62nd identification information may be included, but the 62nd identification information may not be included. If the PDU session change command message includes the 41st identification information and the 62nd identification information, the information indicated by the 62nd identification information is preferentially interpreted and indicated by the 41st identification information. The information may be ignored, or the information indicated by the 62nd identification information may be ignored and the information indicated by the 41st identification information may be preferentially interpreted.

Here, the content indicated by the 41st identification information may be as described above, but may indicate, for example, the period (timer value) during which the establishment of the second PDU session is not permitted.

For example, if the timer value indicated by the 41st identification information is 0, the UE sets the timer value as a timer that restricts the execution of the PDU session establishment procedure in section 4.3, and the set timer expires. Then the PDU session establishment procedure in section 4.3 can be performed.

If the timer value indicated by the 41st identification information is a value other than 0, the UE sets the timer value as a timer that restricts the execution of the PDU session establishment procedure in section 4.3, and the set value is set. You can wait until the timer expires and after that expire the PDU session establishment procedure in section 4.3.

It should be noted that "after the timer expires, execute the PDU session establishment procedure in Chapter 4.3" means "immediately after the timer expires, the UE executes the PDU session establishment procedure in Chapter 4.3". It may mean that “the UE executes the PDU session establishment procedure in section 4.3 at an arbitrary timing after the timer expires”.

[4.4.3. Case 3]
Next, unlike Case 1 and Case 2, Case 3 restricts the establishment of the second PDU session in the PDU session establishment procedure in Section 4.3, which is executed to establish the second PDU session. This is the case.

Specifically, after completing the PDU session establishment procedure in Chapter 4.2, the UE performed the PDU session establishment procedure in Chapter 4.3, but in the PDU session establishment procedure in Chapter 4.3, the second PDU session This is a case where establishment is restricted. More specifically, the UE transmits a PDU session establishment request message to the SMF_222 in the PDU session establishment procedure in section 4.3, and from the SMF_222, a PDU session including at least one of the 51st to 52th identification information. This is a case where the establishment of the second PDU session is restricted by receiving the establishment rejection message.

Here, the contents indicated by the 51st identification information and the 52nd identification information may be as described above.

That is, the UE completes the PDU session establishment procedure in Chapter 4.2, and establishes the first PDU session, and then in the PDU session establishment procedure in Chapter 4.3 executed at an arbitrary timing, the identification information of the 51st to 52nd If a PDU session establishment rejection message containing at least one of these is received, the PDU session establishment procedure in section 4.3 may be executed again until the period indicated by the 52nd identification information has elapsed (timer has expired). Can not. Then, after the period indicated by the 52nd identification information has passed (the timer has expired), the UE can again execute the PDU session establishment procedure in Section 4.3. In other words, the UE that received the timer value included in the PDU session establishment rejection message in section 4.3 from SMF_222 sets the timer value again as a timer that limits the execution of the PDU session establishment procedure in section 4.3, and the UE After the set timer expires, the procedure for establishing the second PDU session (the PDU session establishment procedure in section 4.3) can be started. That is, the UE can send the PDU session establishment request message again to SMF_222 after the timer expires.

[4.4.4. Case 4]
Case 4, like Case 3, is a case where the establishment of the second PDU session is restricted in the PDU session establishment procedure in Section 4.3 that is executed to establish the second PDU session.

However, in case 4, the establishment of the second PDU session is restricted by the PDU session establishment permission message, whereas in case 3, the establishment of the second PDU session is restricted by the PDU session establishment rejection message. different.

Specifically, after completing the PDU session establishment procedure in Chapter 4.2, the UE performed the PDU session establishment procedure in Chapter 4.3, but in the PDU session establishment procedure in Chapter 4.3, the second PDU session This is a case where establishment is restricted. More specifically, the UE transmits the PDU session establishment request message to the SMF_222 in the PDU session establishment procedure in section 4.3, and from the SMF_222, the PDU session including at least one of the 40th to 41st identification information. This is a case where the establishment of the second PDU session is restricted by receiving the establishment permission message.

Here, the contents indicated by the 40th identification information and the 41st identification information are as described above.

In addition, since the UE has received the PDU session establishment permission message in the PDU session establishment procedure in section 4.3 that is executed to establish the second PDU session, this procedure itself succeeds (completes normally). However, the second PDU session may not be established. Here, "unable to establish a second PDU session" may mean "a second PDU session is established, but this PDU session cannot be used".

That is, the UE completes the PDU session establishment procedure in Chapter 4.2, establishes the first PDU session, and then, in the PDU session establishment procedure in Chapter 4.3 executed at an arbitrary timing, identifies the 40th to 41st identification information. When the PDU session establishment acceptance message including at least one of them is received, the second PDU session cannot be established until the period indicated by the 41st identification information has elapsed (timer has expired). Then, the UE becomes able to establish the second PDU session after the period indicated by the 41st identification information has elapsed (the timer has expired). Here, "the second PDU session can be established" may mean "the second PDU session was established, but this PDU session can be used".

In other words, the UE that has received the timer value included in the PDU session establishment acceptance message in section 4.3 sets the timer value as a timer that limits the establishment of the second PDU session, and the UE sets the set timer. Upon expiration, a second PDU session can be established.

However, after receiving the PDU session establishment acceptance message, before the period indicated by the 41st identification information elapses (timer expires), by transmitting a PDU session change command message from the core network side, the UE, It can be set so that a second PDU session can be established before the period indicated by the 41st identification information has elapsed (the timer has expired), or the period indicated by the 41st identification information ( It can also be set to extend or shorten (the period during which the second PDU session cannot be established).

In addition, even after the period indicated by the 41st identification information has elapsed (the timer has expired) after receiving the PDU session establishment acceptance message, if the second PDU session is not established, the core network By transmitting the PDU session change command message from the side, the period indicated by the 41st identification information (the period during which the second PDU session cannot be established) can be reset.

Further, the UE, in the PDU session establishment procedure of Chapter 4.3, when receiving a PDU session establishment acceptance message including at least 40th identification information, by transmitting a PDU session change command message from the core network side, the UE, It can be set so that the second PDU session can be established, and communication using the second PDU session can be executed. In this case, the PDU session establishment acceptance message may not include the 41st identification information.

Specifically, the UE receives the PDU session change command message including at least one of the 61st to 62nd identification information from the SMF_222 after completing the PDU session establishment procedure in Section 4.3, It is possible to change the timing of establishing the second PDU session.

Note that the 61st identification information is preferably information indicating a PDU session ID for identifying the PDU session established as the second PDU session.

The 62nd identification information is information indicating that the establishment of the second PDU session is permitted, and / or information indicating that the establishment of the second PDU session is possible, and The information may be information indicating that communication using the second PDU session is permitted, and / or information indicating that communication using the second PDU session is possible.

Further, the 62nd identification information may be information indicating a request for revalidation of the PDU session, specifically, may be the 39th 5GSM reason value (5GSM cause), revalidation It may be information indicating a reactivation request.

For example, if the timer value indicated by the 41st identification information is 0, the UE sets the timer value as a timer that limits the establishment of the second PDU session, and after the set timer expires. , A second PDU session can be established.

If the timer value indicated by the 41st identification information is a value other than 0, the UE sets the timer value as a timer that limits the establishment of the second PDU session, and the set timer is Wait until it expires, and after that timer expires, a second PDU session can be established.

Incidentally, "after the timer expires, to establish a second PDU session" may mean "immediately after the timer expires, the UE establishes a second PDU session", It may mean that the UE establishes a second PDU session at an arbitrary timing after the timer expires.

[5. Second Embodiment]
Next, a second embodiment will be described. Here, the second embodiment is also referred to as the present embodiment.

In this chapter, "Registration procedure" in Chapter 5.1, "PDU session establishment procedure for establishing the first PDU session" in Chapter 5.2, "PDU session establishment procedure for establishing the second PDU session" in Chapter 5.3 , Section 5.4, "Case to prevent the PDU session establishment procedure to establish the second PDU session immediately after executing the PDU session establishment procedure to establish the first PDU session", Chapter 5.5 The procedure for changing the PDU session anchor that provides the second PDU session of SSC mode 3 "will be described in this order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in Section 5.1.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Chapter 5.2, and performs communication using the first PDU session between the UE and the DN. Transition to a state where

Next, each device establishes a second PDU session by executing the PDU session establishment procedure described in Chapter 5.3, and performs communication using the second PDU session between the UE and the DN. Transition to a state in which it is possible. At this time, the UE can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state capable of redundant communication.

Next, in Section 5.4, a case is explained in which each device restricts the PDU session establishment procedure that establishes the second PDU session immediately after performing the PDU session establishment procedure described in Chapter 5.2. ..

Finally, when each device executes the procedure described in Chapter 5.5 and the SSC mode of the second PDU session is SSC mode 3, the PDU session anchor that provides the PDU session of SSC mode 3 is changed. By establishing the third (new) PDU session by executing the procedure and then releasing the second (existing) PDU session, the PDU session anchor (that is, UPF) is maintained while continuing the session. Explain the procedure to change.

[5.1. Registration procedure]
The registration procedure in the present embodiment may be the same as the registration procedure in the first embodiment (registration procedure in Chapter 4.1), so description thereof will be omitted. Each device (especially UE_10 and AMF_210) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure.

[5.2. PDU session establishment procedure for establishing the first PDU session]
Next, an outline of a PDU session establishment procedure to establish a PDU session for a DN will be described with reference to FIG. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in section 4.2, but the identification information contained in the PDU session establishment request message and / or NAS message and the identification information contained in the PDU session establishment acceptance message are Different from Chapter 4.2. However, since there are many points in common with the explanation in Chapter 4.2, explanations of common points are omitted, and in the following, different points will be mainly described. The UE, gNB_110, AMF_210, SMF_220, and UPF_230 are the same as in Chapter 4.2.

First, the UE can send at least one of the identification information from 21st to 26th and 28th in the PDU session establishment request message and / or the NAS message. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st to 26th and 28th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 22nd identification information indicates that the first PDU session is established. It is preferable to indicate that it is a PDU session, and the SSC mode indicated by the 23rd identification information may be SSC mode 1, SSC mode 2, or SSC mode 3. Further, the DNN indicated by the 25th identification information is preferably the DNN indicated by the 14th identification information included in the registration acceptance message in Section 5.1. Further, the S-NSSAI represented by the 26th identification information is preferably the S-NSSAI represented by the 15th identification information included in the registration acceptance message in Section 5.1.

UE_10 can notify the network of the content of these identification information by transmitting these identification information. Also, these pieces of identification information may be included in these messages to indicate the request of the UE_10. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Upon receiving the PDU session establishment request message, SMF_220 can recognize that the UE is requesting and / or various identification information included in the PDU session establishment request message.

Also, SMF_222 and / or AMF_210 can include at least one of the 31st to 36th and 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st to 36th and 38th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 32nd identification information is the first PDU session to be established. The SSC mode indicated by the 33rd identification information may be SSC mode 1, SSC mode 2, or SSC mode 3.

Furthermore, the content indicated by the 35th identification information may be the same as or different from the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Further, it is preferable that the DNN indicated by the 35th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Section 5.1. Furthermore, the content indicated by the 36th identification information may be the same as or different from the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Furthermore, the S-NSSAI indicated by the 36th identification information is preferably the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Section 5.1.

Also, the PDU session ID indicated by the 38th identification information may be the same as or different from the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. The SMF_220 and / or the AMF_210 can notify the UE_10 of the content of the identification information by transmitting at least one of the identification information. Note that SMF_220 and / or AMF_210 may indicate that the network supports each function or may indicate that the request of UE_10 has been accepted, by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

UE_10, by receiving the PDU session establishment acceptance message, it is possible to recognize that the request of UE_10 by the PDU session establishment request is accepted, and / or the content of each identification information included in the PDU session establishment acceptance message. ..

-When this procedure is completed, each device may be in the state where the first PDU session for the DN is established.

[5.3. PDU session establishment procedure for establishing the second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in section 4.3, but the identification information included in the PDU session establishment request message and / or the NAS message and the identification information included in the PDU session establishment acceptance message are Different from chapter 4.3. However, since there are many points in common with the explanation in Chapter 4.3, the explanation of the common points will be omitted, and the different points will be mainly explained below. Each device related to this procedure is UE, gNB_110, gNB_112, AMF_210, SMF_222, UPF_232, DN_300, which is the same as in Section 4.3.

First, the UE can send the PDU session establishment request message and / or the NAS message by including at least one of the 21st to 28th identification information. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Furthermore, the contents indicated by the 21st to 28th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 22nd identification information indicates that the PDU session to be established is the second PDU session. It is preferable to show that Further, it is preferable that the content indicated by the 23rd identification information is the same as the content indicated by the 33rd identification information included in the PDU session establishment acceptance message in Section 5.2. Also, the content indicated by the 24th identification information is preferably the same as the content indicated by the 34th identification information included in the PDU session establishment acceptance message in Section 5.2.

Also, the content indicated by the 25th identification information is preferably the same as the content indicated by the 35th identification information included in the PDU session establishment acceptance message in Chapter 5.2. Further, the DNN indicated by the 25th identification information is preferably the DNN indicated by the 14th identification information included in the registration acceptance message in Section 5.1. Further, the content indicated by the 26th identification information is preferably the same as the content indicated by the 36th identification information included in the PDU session establishment acceptance message in Section 5.2. Further, the S-NSSAI represented by the 26th identification information is preferably the S-NSSAI represented by the 15th identification information included in the registration acceptance message in Section 5.1.

Further, the content indicated by the 27th identification information is preferably the same as the content indicated by the 28th identification information included in the PDU session establishment request message in Chapter 5.2, and the PDU session establishment acceptance message in Chapter 5.2. It is preferable that the content is the same as the content indicated by the 38th identification information included in. Further, the content indicated by the 28th identification information is preferably different from the content indicated by the 28th identification information included in the PDU session establishment request message in Section 5.2, and is included in the PDU session establishment acceptance message in Section 5.2. It is preferable that the content is different from the content indicated by the 38th identification information.

Also, SMF_222 and / or AMF_210 can include at least one of the 31st to 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st to 38th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 32nd identification information indicates that the PDU session to be established is the second PDU. It is preferable to indicate that it is a session. The content indicated by the 33rd identification information may be the same as or different from the content indicated by the 23rd identification information included in the PDU session establishment request message of this chapter. The content indicated by the 34th identification information may be the same as or different from the content indicated by the 24th identification information included in the PDU session establishment request message of this chapter.

The content indicated by the 35th identification information may be the same as or different from the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Further, it is preferable that the DNN indicated by the 35th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Section 5.1. The content indicated by the 36th identification information may be the same as or different from the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Furthermore, the S-NSSAI indicated by the 36th identification information is preferably the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Section 5.1.

The content indicated by the 37th identification information may be the same as or different from the content indicated by the 27th identification information included in the PDU session establishment request message of this chapter. The content indicated by the 38th identification information may be the same as or different from the content indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Further, the PDU session ID indicated by the 38th identification information is preferably different from the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message in Chapter 5.2, and the PDU session in Chapter 5.2. It is preferable that it is different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message, and the same as the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Is preferred, but may be different. The SMF_222 and / or the AMF_210 can notify the UE of the content of the identification information by transmitting the identification information. Note that the SMF_222 and / or the AMF_210 may indicate that the network supports each function or may indicate that the request from the UE has been accepted, by transmitting the identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

The above is the difference between this procedure and the procedure in Chapter 4.3. For the parts not described in this chapter, the description in Chapter 4.3 can be applied.

[5.4. Case where the PDU session establishment procedure for establishing the second PDU session is immediately executed after the PDU session establishment procedure for establishing the first PDU session is executed]
This case in the present embodiment may be the same as the description in Section 4.4 in the first embodiment, and therefore its description is omitted.

[5.5. Procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3]
Next, if the second PDU session is established by executing the PDU session establishment procedure in Chapter 5.3 and the SSC mode of the PDU session is SSC mode 3, the PDU session is provided. A PDU session anchor (PSA) change procedure to be performed will be described with reference to FIG. This procedure is triggered by the network (SMF) and after establishing a new PDU session for the same DN using the new PDU session anchor, the existing (old) PDU associated with the old PDU session anchor is This is a procedure for releasing a session. Note that the AMF is not changed by this procedure, but the SMF may be changed.

-The UE uses the second PDU session to send and receive user data. Specifically, the UE transmits / receives uplink data and / or downlink data to / from DN_300 via UPF_232 (S1100).

When SMF_222 determines that UPF and / or SMF needs to be changed (S1102), SMF_222 informs AMF_210 of a PDU session change command message including at least one of the 61st to 62th identification information. Sends N1 SM (Session Management) container including S1104 (S1104). The N1SM container may be a NAS message. Further, the NAS message may be a downlink NAS transport (DL NAS transport) message. Here, the contents indicated by the 61st to 62nd identification information may be as described above, but the 61st identification information is the PDU session ID for identifying the PDU session established as the second PDU session. The 62nd identification information may be information indicating that a PDU session for the same DN needs to be reestablished.

Further, as a method of transmitting the 61st identification information, SMF_222 separately transmits the N1SM (Session Management) container including the PDU session change command message including the 62nd identification information and the 61st identification information. May be. These may also be sent as NAS messages.

AMF_210 transfers the NAS message received from SMF_222 to the UE (S1106).

Note that SMF_222 and / or AMF_210 may indicate that the identification information is transmitted to establish a new PDU session and release the old PDU session. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Upon receiving the NAS message, the UE may decide to start the PDU session establishment procedure for the same DN (S1108). The UE is requested to establish a new PDU session and release the old PDU session by receiving the PDU session change command message, and / or each identification information included in the PDU session change command message. Can recognize the contents. This PDU session establishment procedure is basically the same as the PDU session establishment procedure in section 5.3, but it is necessary to replace SMF_222 with SMF_224 and UPF_232 with UPF_234. Also, the identification information included in the PDU session establishment request message and / or the NAS message and the identification information included in the PDU session establishment acceptance message differ from those in Section 5.3. However, since there are many points in common with the explanation in Chapter 5.3, explanations of common points are omitted, and in the following, different points will be mainly described. The UE, gNB_110, gNB_112, AMF_210, and DN are the same as in Chapter 5.3.

First, the UE starts a PDU session establishment procedure by transmitting a NAS message containing a PDU session establishment request message to SMF_224 via 5GAN and AMF_210 (S900) (S902) (S904). , GNB_110 instead of gNB_110, the NAS message including the PDU session establishment request message is transmitted (S900).

Here, the UE, in the PDU session establishment request message and / or NAS message, it is possible to include at least one of the identification information from the 21st to 29, but a control message different from these, for example, It may be included in a control message of a layer lower than the NAS layer (for example, RRC layer, MAC layer, RLC layer, PDCP layer) and transmitted. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Furthermore, the contents indicated by the 21st to 29th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 22nd identification information indicates that the PDU session to be established is the second PDU session. It is preferable to show that Further, the content indicated by the 23rd identification information is the 33rd identification information included in the PDU session establishment acceptance message in Chapter 5.3, and / or the 23rd identification information included in the PDU session establishment request message in Chapter 5.3. It is preferably the same as the content shown. Further, the content shown in the 24th identification information is the 34th identification information included in the PDU session establishment acceptance message in Chapter 5.3, and / or the 24th identification information included in the PDU session establishment request message in Chapter 5.3. It is preferably the same as the content shown. Further, the content indicated by the 25th identification information is the 35th identification information included in the PDU session establishment acceptance message in Chapter 5.3, and / or the 25th identification information included in the PDU session establishment request message in Chapter 5.3. It is preferably the same as the content shown. Further, the content indicated by the 26th identification information is the 36th identification information included in the PDU session establishment acceptance message in Chapter 5.3, and / or the 26th identification information included in the PDU session establishment request message in Chapter 5.3. It is preferably the same as the content shown.

Also, the PDU session ID indicated by the 27th identification information preferably indicates the PDU session ID established by the PDU session establishment procedure in Chapter 5.2. The PDU session ID indicated by the 28th identification information is preferably different from the PDU session ID indicated by the 27th identification information in this chapter, and different from the PDU session ID indicated by the 29th identification information in this chapter. Preferably. Also, the PDU session ID indicated by the 28th identification information may indicate a newly established PDU session ID. Further, it is preferable that the PDU session ID indicated by the 29th identification information indicates the PDU session ID established by the PDU session establishment procedure in Chapter 5.3. The UE can notify the network of the contents of these pieces of identification information by transmitting these pieces of identification information. These pieces of identification information may indicate the request of the UE by being included in these messages. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Also, when the AMF_210 receives the PDU session establishment request message, it selects SMF_224 as its transfer destination (S902) and transfers the PDU session establishment request message to SMF_224 via the N11 interface (S904).

Further, when the SMF_224 receives the PDU session establishment request message from the AMF_210 (S904), the SMF_224 can recognize that the UE requests and various identification information included in the PDU session establishment request message.

Also, SMF_224 selects UPF_234 as the UPF of the establishment destination of the PDU session and sends a session establishment request message to UPF_234 via the N4 interface (S906).

Upon receiving the session establishment request message from SMF_224, UPF_234 creates a context for the PDU session and sends a session establishment response message to SMF_224 via the N4 interface (S908).

When SMF_224 receives the session establishment response message from UPF_234, SMF_224 may perform the address assignment of the address assigned to the UE. SMF_224 transmits a PDU session establishment acceptance message to the UE via AMF_210 (S910) (S912). Specifically, the SMF_224 transmits a PDU session establishment acceptance message to the AMF_210 via the N11 interface (S910), and the AMF_210 having received this includes the PDU session establishment acceptance message to the UE via the N1 interface. Send a NAS message (S912). At this time, when gNB_112 has directly transmitted the PDU session establishment request message to AMF_210, AMF_210 may directly transmit the PDU session establishment acceptance message to gNB_112. Further, when the gNB_112 has transmitted the PDU session establishment request message to the AMF_210 via the gNB_110, the AMF_210 may transmit the PDU session establishment acceptance message to the gNB_112 via the gNB_110. The gNB_112 sends a NAS message including a PDU session establishment acceptance message to the UE.

Here, SMF_224 and / or AMF_210 may include at least one of the 31st to 39th identification information in the PDU session establishment acceptance message and may transmit it. Here, the contents indicated by the 31st to 39th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 32nd identification information indicates that the PDU session to be established is the second PDU. It is preferable to indicate that it is a session. Further, the content indicated by the 33rd identification information may be the same as the content indicated by the 23rd identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 34th identification information may be the same as the content indicated by the 24th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 35th identification information may be the same as the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Further, the content indicated by the 36th identification information may be the same as the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 37th identification information may be the same as the content indicated by the 27th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 38th identification information may be the same as the content indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 39th identification information may be the same as the content indicated by the 29th identification information included in the PDU session establishment request message of this chapter. The SMF_224 and / or the AMF_210 can notify the UE of the content of the identification information by transmitting the identification information. Note that SMF_224 and / or AMF_210 may indicate that the network supports each function or may indicate that the request of the UE has been accepted by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

The above is the difference between this procedure and the procedure in Chapter 5.3. For the parts not described in this chapter, the description in Chapter 5.3 can be applied.

A new PDU session for redundant communication can be established as described above. That is, when this procedure is completed, the UE can transmit / receive uplink data and / or downlink data via UPF_234, which is a new UPF (S1110). In other words, the UE uses the PDU session established by the PDU session establishment procedure of Chapter 5.2, the PDU session established by the PDU session establishment procedure of Chapter 5.3, and the PDU session established by the procedure of this chapter, Redundant communication can be performed.

Then, after the new PDU session is established, each device may execute the PDU session release procedure (S1112) to release the old PDU session (the PDU session established by the PDU session establishment procedure in Chapter 5.3). it can. The PDU session release procedure may be started by the expiration of the timer in the UE or the timer in the SMF.

By the above, the PDU session anchor for performing redundant communication can be changed from UPF_232 to UPF_234. That is, the UE can perform redundant communication using the PDU session established by the procedure of this chapter and the PDU session established by the procedure of this chapter.

[6. Third Embodiment]
Next, a third embodiment will be described. Here, the third embodiment is also referred to as the present embodiment.

In this chapter, "Registration procedure" in section 6.1, "PDU session establishment procedure for establishing the first PDU session" in section 6.2, "PDU session establishment procedure for establishing the second PDU session" in section 6.3 , Section 6.4, "Case to prevent the PDU session establishment procedure to establish the second PDU session immediately after executing the PDU session establishment procedure to establish the first PDU session", Section 6.5 The procedure for changing the PDU session anchor that provides the second PDU session of SSC mode 3 "will be described in this order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in section 6.1.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Chapter 6.2, and performs communication using the first PDU session between the UE and the DN. Transition to a state where

After that, each device establishes the second PDU session by executing the PDU session establishment procedure described in Chapter 6.3, and performs communication using the second PDU session between the UE and the DN. Transition to a state where At this time, the UE can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state capable of redundant communication.

Next, in Section 6.4, a case where each device restricts the PDU session establishment procedure that establishes the second PDU session immediately after performing the PDU session establishment procedure described in Chapter 6.2 is explained. ..

Finally, when each device executes the procedure described in Chapter 6.5 and the SSC mode of the second PDU session is SSC mode 3, the PDU session anchor that provides the PDU session of SSC mode 3 is changed. By establishing the third (new) PDU session by executing the procedure and then releasing the second (existing) PDU session, the PDU session anchor (that is, UPF) is maintained while continuing the session. Explain the procedure to change.

[6.1. Registration procedure]
The registration procedure in this embodiment may be the same as the registration procedure in the second embodiment (registration procedure in Chapter 5.1), and therefore description thereof will be omitted. Each device (especially UE_10 and AMF_210) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure.

[6.2. PDU session establishment procedure for establishing the first PDU session]
The PDU session establishing procedure for establishing the first PDU session in the present embodiment is a PDU session establishing procedure for establishing the first PDU session in the second embodiment (the PDU session establishing procedure in Chapter 5.2). Since they may be the same, the description thereof will be omitted. Upon completion of this procedure, each device may be in a state where the first PDU session for the DN is established.

[6.3. PDU session establishment procedure for establishing the second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in section 5.3, but the identification information contained in the PDU session establishment request message and / or NAS message and the identification information contained in the PDU session establishment acceptance message are Different from Chapter 5.3. However, since there are many points in common with the explanation in Chapter 5.3, explanations of common points are omitted, and in the following, different points will be mainly described. Each device related to this procedure is UE, gNB_110, gNB_112, AMF_210, SMF_222, UPF_232, DN_300, which is the same as in Chapter 5.3.

First, the UE can send at least one of the identification information from 21st to 26th and 28th in the PDU session establishment request message and / or the NAS message. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st to 26th and 28th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 22nd identification information indicates that the second PDU session is established. It is preferable to indicate that it is a PDU session. Further, it is preferable that the content indicated by the 23rd identification information is different from the content indicated by the 33rd identification information included in the PDU session establishment acceptance message in Section 6.2. Further, it is preferable that the content indicated by the 24th identification information is different from the content indicated by the 34th identification information included in the PDU session establishment acceptance message in Section 6.2.

Also, the content indicated by the 25th identification information is preferably different from the content indicated by the 35th identification information included in the PDU session establishment acceptance message in section 6.2. Further, it is preferable that the DNN indicated by the 25th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Section 6.1. Further, the content indicated by the 26th identification information is preferably different from the content indicated by the 36th identification information included in the PDU session establishment acceptance message in Section 6.2. Furthermore, the S-NSSAI indicated by the 26th identification information is preferably the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Section 6.1.

Further, the content indicated by the 28th identification information is preferably different from the content indicated by the 28th identification information included in the PDU session establishment request message in Chapter 6.2, and is included in the PDU session establishment acceptance message in Chapter 6.2. It is preferable that the content is different from the content indicated by the 38th identification information.

Also, SMF_222 and / or AMF_210 can include at least one of the 31st to 36th and 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st to 36th and 38th identification information may be as described above, but the Redundancy Sequence Number (RSN) indicated by the 32nd identification information indicates that the second PDU session is established. It is preferable to indicate that the PDU session is. The content indicated by the 33rd identification information may be the same as or different from the content indicated by the 23rd identification information included in the PDU session establishment request message of this chapter. The content indicated by the 34th identification information may be the same as or different from the content indicated by the 24th identification information included in the PDU session establishment request message of this chapter.

The content indicated by the 35th identification information may be the same as or different from the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Furthermore, it is preferable that the DNN indicated by the 35th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Section 6.1. The content indicated by the 36th identification information may be the same as or different from the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Furthermore, it is preferable that the S-NSSAI indicated by the 36th identification information is the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Section 6.1.

The content indicated by the 38th identification information may be the same as or different from the content indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Further, the PDU session ID shown in the 38th identification information is preferably different from the PDU session ID shown in the 28th identification information included in the PDU session establishment request message in Chapter 6.2, and the PDU session in 6.2 chapter. It is preferable that it is different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message, and the same as the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Is preferred, but may be different. The SMF_222 and / or the AMF_210 can notify the UE of the content of the identification information by transmitting the identification information. Note that the SMF_222 and / or the AMF_210 may indicate that the network supports each function or may indicate that the request from the UE has been accepted, by transmitting the identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

[6.4. Case in which the PDU session establishment procedure for establishing the second PDU session is immediately executed after the PDU session establishment procedure for establishing the first PDU session is executed]
Since this case in the present embodiment may be the same as the description in Section 5.4 in the second embodiment, the description thereof will be omitted.

[6.5. Procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3]
The “procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3” in the present embodiment is the “change the PDU session anchor that provides the second PDU session in SSC mode 3” in the second embodiment. Since it may be the same as the “procedure” (procedure in Chapter 5.5), its explanation is omitted.

[7. Fourth Embodiment]
Next, a fourth embodiment will be described. Here, the fourth embodiment is also referred to as the present embodiment.

In this chapter, "Registration procedure" in section 7.1, "PDU session establishment procedure for establishing the first PDU session" in section 7.2, "PDU session establishment procedure for establishing the second PDU session" in section 7.3 , Section 7.4, "Case to prevent the PDU session establishment procedure to establish the second PDU session immediately after executing the PDU session establishment procedure to establish the first PDU session", Section 7.5 The procedure for changing the PDU session anchor that provides the second PDU session of SSC mode 3 "will be described in this order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in section 7.1.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Chapter 7.2, and performs communication using the first PDU session between the UE and the DN. Transition to a state where

After that, each device establishes the second PDU session by executing the PDU session establishment procedure described in Chapter 7.3, and performs communication using the second PDU session between the UE and the DN. Transition to a state where At this time, the UE can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state capable of redundant communication.

Next, Section 7.4 describes a case where each device restricts the PDU session establishment procedure that establishes the second PDU session immediately after performing the PDU session establishment procedure described in Section 7.2. ..

Finally, when each device executes the procedure described in Chapter 7.5 and the SSC mode of the second PDU session is SSC mode 3, the PDU session anchor that provides the PDU session of SSC mode 3 is changed. By establishing the third (new) PDU session by executing the procedure and then releasing the second (existing) PDU session, the PDU session anchor (that is, UPF) is maintained while continuing the session. Explain the procedure to change.

[7.1. Registration procedure]
The registration procedure in this embodiment may be the same as the registration procedure in the third embodiment (registration procedure in section 6.1), and therefore its explanation is omitted. Each device (especially UE_10 and AMF_210) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure.

[7.2. PDU session establishment procedure for establishing the first PDU session]
The PDU session establishment procedure for establishing the first PDU session in the present embodiment is a PDU session establishment procedure for establishing the first PDU session in the third embodiment (the PDU session establishment procedure in Chapter 6.2) and Since they may be the same, the description thereof will be omitted. Upon completion of this procedure, each device may be in a state where the first PDU session for the DN is established.

[7.3. PDU session establishment procedure for establishing the second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in section 6.3, but the identification information contained in the PDU session establishment request message and / or NAS message and the identification information contained in the PDU session establishment acceptance message are Different from Chapter 6.3. However, since there are many points in common with the description in Chapter 6.3, explanations of common points are omitted, and in the following, different points will be mainly described. Each device related to this procedure is a UE, gNB_110, gNB_112, AMF_210, SMF_222, UPF_232, DN_300, and is the same as in Chapter 6.3.

First, the UE can send the PDU session establishment request message and / or the NAS message by including at least one of the 21st to 28th identification information. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Furthermore, the contents indicated by the identification information of 21st to 26th and 28th may be the same as those in Chapter 6.3. The content of the 27th identification information may be the same as in Section 5.3. The UE can notify the network of the contents of these pieces of identification information by transmitting these pieces of identification information. These pieces of identification information may indicate the request of the UE by being included in these messages. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Also, SMF_222 and / or AMF_210 can include at least one of the 31st to 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st to 36th and 38th identification information may be the same as in Chapter 6.3. The contents of the 37th identification information may be the same as in Section 5.3. The SMF_222 and / or the AMF_210 can notify the UE of the content of the identification information by transmitting the identification information. Note that the SMF_222 and / or the AMF_210 may indicate that the network supports each function or may indicate that the request from the UE has been accepted, by transmitting the identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

The above is the difference between this procedure and the procedure in Chapter 6.3. For the parts not described in this chapter, the description in Chapter 6.3 can be applied.

[7.4. Case in which the PDU session establishment procedure for establishing the second PDU session is immediately executed after the PDU session establishment procedure for establishing the first PDU session is executed]
This case in the present embodiment may be the same as the description in Chapter 6.4 in the third embodiment, and therefore its description is omitted.

[7.5. Procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3]
The “procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3” in the present embodiment is “change the PDU session anchor that provides the second PDU session in SSC mode 3” in the third embodiment. Since it can be the same as the “procedure” (procedure in Chapter 6.5), its explanation is omitted.

[8. Fifth Embodiment]
Next, a fifth embodiment will be described. Hereinafter, the fifth embodiment will also be referred to as the present embodiment. In the present embodiment, a device is provided with two independent UEs, and each UE establishes a PDU session, thereby enabling redundant communication. The form is different.

Further, the two UEs (UE_10 and UE_12) in the present embodiment may be able to directly exchange information via a bus in the device, or exchange information via a storage unit in the device. Alternatively, information may be exchanged via the antennas of the respective devices. That is, the information originally stored by UE_10 or the information acquired by executing various procedures may be provided to UE_12. Similarly, the information originally stored by the UE_12 or the information acquired by executing various procedures may be provided to the UE_10.

In this chapter, "Registration procedure" in chapter 8.1, "PDU session establishment procedure for establishing the first PDU session" in chapter 8.2, "PDU session establishment procedure for establishing the second PDU session" in chapter 8.3 , Section 8.4, “Cases in which the PDU session establishment procedure that establishes the second PDU session immediately after the PDU session establishment procedure that establishes the first PDU session is executed is restricted” are explained in order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in section 8.1. This procedure is performed by UE_10 and UE_12.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Chapter 8.2, and performs communication using the first PDU session between UE_10 and DN. Transition to a state where

After that, each device establishes the second PDU session by executing the PDU session establishment procedure described in Chapter 8.3, and performs communication using the second PDU session between UE_12 and DN. Transition to a state where At this time, the device can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state in which redundant communication is possible.

Finally, Section 8.4 describes the case where each device is restricted from executing the PDU session establishment procedure that establishes the second PDU session immediately after performing the PDU session establishment procedure described in Chapter 8.2. ..

[8.1. Registration procedure]
Here, the case where UE_10 first executes the registration procedure and then UE_12 executes the registration procedure will be described. Of course, UE_12 may execute the registration procedure first, and then UE_10 may execute the registration procedure.

First, the registration procedure started by UE_10 will be explained.

The registration procedure initiated by UE_10 is basically the same as the registration procedure in the first embodiment (registration procedure in Chapter 4.1), but is included in the identification information included in the registration request message and the registration acceptance message. The identification information is different from Chapter 4.1. However, since there are many points in common with the explanation in Chapter 4.1, explanations of common points are omitted, and in the following, different points will be mainly described.

First, UE_10, the registration request message and / or RRC message can be transmitted including at least one of the first, second identification information, AMF_210, it is possible to receive this registration request message. .. Here, the content indicated by the first and second identification information may be as described above. Moreover, UE_10 can notify the network of the content of these identification information by transmitting these identification information. These pieces of identification information may indicate the request of the UE by being included in this message. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Upon receiving the registration request message, AMF_210 can recognize that UE_10 is requesting it and / or various identification information included in the registration request message.

Also, AMF_210 can transmit the registration acceptance message including at least one of the 11th, 12th, 14th, and 15th identification information, and UE_10 can receive this registration acceptance message. Further, the AMF_210 can transmit the registration acceptance message including the information identifying the UE_10, and the UE_10 can receive the registration acceptance message. Here, the contents indicated by the eleventh, twelfth, fourteenth and fifteenth identification information may be as described above. AMF_210 can notify UE_10 of the content of these pieces of identification information by transmitting at least one of these pieces of identification information. In addition, AMF_210 may indicate that the network supports each function by transmitting these pieces of identification information, or may indicate that the request of the UE has been accepted. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

By receiving the registration acceptance message, UE_10 can recognize that the request of UE_10 by the registration request message has been accepted and / or the content of each identification information included in the registration acceptance message.

The above is the difference between this procedure and the registration procedure in Chapter 4.1. For the parts not described in this chapter, the registration procedure in Chapter 4.1 can be applied.

When this procedure is completed, each device (especially UE_10 and AMF_210) can transition to the registered state (RM-REGISTERED state).

Next, the registration procedure started by UE_12 will be explained. This registration procedure is also basically the same as the registration procedure by UE_10 in this chapter, but replaces UE_10 with UE_12, gNB_110 with gNB_112, AMF_210 with AMF_212, SMF_220 with SMF_222, and UPF_230 with UPF_232. There is a need. Also, the identification information included in the registration request message and the identification information included in the registration acceptance message differ from the registration procedure by UE_10 in this chapter. However, since there are many points in common with the registration procedure by UE_10 in this chapter, explanations of common points are omitted, and in the following, different points will be mainly described.

First, UE_12, the registration request message and / or RRC message can be transmitted by including at least one of the first to third identification information, AMF_212, it is possible to receive this registration request message. .. Here, the content indicated by the first to third identification information may be as described above, but the group indicated by the second identification information may be a group different from the group to which UE_10 belongs. In other words, the content indicated by the second identification information is preferably different from the content indicated by the second identification information included in the registration request message of the registration procedure initiated by UE_10, and the registration initiated by UE_10. It is preferable that the contents are different from the contents indicated by the twelfth identification information included in the registration acceptance message of the procedure. Also, the information for identifying the UE indicated by the third identification information may be information for identifying UE_10. In other words, the information identifying the UE indicated by the third identification information may be the same as the information identifying the UE_10 included in the registration acceptance message of the registration procedure initiated by the UE_10.

UE_12 can also notify the network of the content of these identification information by transmitting these identification information. These pieces of identification information may indicate the request of the UE by being included in this message. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

When AMF_212 receives the registration request message, AMF_212 can recognize that UE_12 makes a request and / or various identification information included in the registration request message.

Also, AMF_212 can include at least one of the 11th to 15th identification information in the registration acceptance message, and UE_12 can receive this registration acceptance message. Further, the AMF_210 can transmit the registration acceptance message including the information identifying the UE_12, and the UE_12 can receive the registration acceptance message. Here, the contents indicated by the eleventh to fifteenth identification information may be as described above, but the contents indicated by the twelfth identification information may be the same as the contents indicated by the second identification information. Good. Furthermore, the content indicated by the thirteenth identification information may be the same as the content indicated by the third identification information.

Also, the group indicated by the 12th identification information may be a group different from the group to which UE_10 belongs. In other words, the content indicated by the twelfth identification information is preferably different from the content indicated by the second identification information included in the registration request message of the registration procedure initiated by UE_10, and the registration initiated by UE_10. It is preferable that the contents are different from the contents indicated by the twelfth identification information included in the registration acceptance message of the procedure. The information for identifying the UE indicated by the thirteenth identification information may be information for identifying UE_10. In other words, the information for identifying the UE indicated by the thirteenth identification information may be the same as the information for identifying UE_10 included in the registration acceptance message of the registration procedure started by UE_10.

Also, the information identifying UE_12 may be different from the information identifying UE_10. In other words, the information identifying the UE_12 may be different from the information indicated by the third identification information of this procedure, or may be different from the information indicated by the thirteenth identification information of this procedure.

AMF_212 can notify UE_12 of the content of these identification information by transmitting at least one of these identification information. Further, the AMF_212 may indicate that the network supports each function or may indicate that the request of the UE_12 has been accepted by transmitting the identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

By receiving the registration acceptance message, UE_12 can recognize that the request of UE_12 by the registration request message has been accepted and / or the content of each identification information included in the registration acceptance message.

The above is the difference between the registration procedure by UE_12 and the registration procedure by UE_10 in this chapter. The registration procedure by UE_10 in this chapter can be applied to the parts not described in this chapter.

Upon completion of this procedure, each device (especially UE_12 and AMF_212) can transit to the registered state (RM-REGISTERED state).

[8.2. PDU session establishment procedure for establishing the first PDU session]
Next, an outline of a PDU session establishment procedure to establish a PDU session for a DN will be described with reference to FIG. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in section 4.2, but the identification information contained in the PDU session establishment request message and / or NAS message and the identification information contained in the PDU session establishment acceptance message are Different from Chapter 4.2. However, since there are many points in common with the explanation in Chapter 4.2, explanations of common points are omitted, and in the following, different points will be mainly described. The UE, gNB_110, AMF_210, SMF_220, and UPF_230 are the same as in Chapter 4.2.

First, UE_10 can include at least one of the 21st, 23rd, and 28th identification information in the PDU session establishment request message and / or the NAS message and transmit the message. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st, 23rd and 28th identification information may be as described above, but the SSC mode indicated by the 23rd identification information is preferably SSC mode 1. Note that the SSC mode indicated by the 23rd identification information is not excluded from being SSC mode 2 and SSC mode 3. UE_10 can notify the network of the content of these identification information by transmitting these identification information. Also, these pieces of identification information may be included in these messages to indicate the request of the UE_10. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Also, SMF_220 and / or AMF_210 can include at least one of the 31st, 33rd and 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st, 33rd, and 38th identification information may be as described above, but the SSC mode indicated by the 33rd identification information is preferably SSC mode 1. Also, the PDU session ID indicated by the 38th identification information may be the same as or different from the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. The SMF_220 and / or the AMF_210 can notify the UE_10 of the content of the identification information by transmitting at least one of the identification information. Note that SMF_220 and / or AMF_210 may indicate that the network supports each function or may indicate that the request of UE_10 has been accepted, by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

[8.3. PDU session establishment procedure for establishing the second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in Chapter 8.2, except that UE_10 is replaced with UE_12, gNB_110 is replaced with gNB_112, AMF_210 is replaced with AMF_212, SMF_220 is replaced with SMF_222, and UPF_230 is replaced with UPF_232. There is a need. Also, the identification information included in the PDU session establishment request message and / or the NAS message and the identification information included in the PDU session establishment acceptance message are different from those in Chapter 8.2. However, since there are many points in common with the explanation in Chapter 8.2, the explanation of the common points will be omitted, and the different points will be mainly explained below. The DN_300 is the same as in Chapter 8.2.

First, UE_12 can include at least one of the 21st, 23rd, and 28th identification information in the PDU session establishment request message and / or the NAS message and transmit the message. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st, 23rd and 28th identification information may be as described above, but the SSC mode indicated by the 23rd identification information is preferably SSC mode 1.

Further, the PDU session ID indicated by the 28th identification information is preferably different from the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of Chapter 8.2, and the PDU session of Chapter 8.2 It is preferably different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message.

UE_12 can notify the network of the contents of these identification information by transmitting these identification information. In addition, these pieces of identification information may indicate the request of the UE_12 by being included in these messages. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

When SMF_222 receives the PDU session establishment request message, SMF_222 can recognize that UE_12 makes a request and / or various identification information included in the PDU session establishment request message.

Also, SMF_222 and / or AMF_212 can include at least one of the 31st, 33rd, and 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st, 33rd, and 38th identification information may be as described above, but the SSC mode indicated by the 33rd identification information is preferably SSC mode 1. In addition, the PDU session ID shown in the 38th identification information is preferably different from the PDU session ID shown in the 28th identification information included in the PDU session establishment request message in Chapter 8.2, and the PDU session in Chapter 8.2 is also included. It is preferable that it is different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message, and the same as the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Is preferred, but may be different. SMF_222 and / or AMF_212 can notify UE_10 of the content of the identification information by transmitting at least one of the identification information. Note that SMF_222 and / or AMF_212 may indicate that the network supports each function or may indicate that the request of UE_12 has been accepted, by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

UE_12, by receiving the PDU session establishment acceptance message, the request of the UE_12 by the PDU session establishment request was accepted, and / or can recognize the content of each identification information included in the PDU session establishment acceptance message. ..

The above is the difference between this procedure and the procedure in Chapter 8.2. For the parts not described in this chapter, the description in Chapter 8.2 can be applied.

By using the second PDU session established as described above together with the first PDU session, device_20 can perform redundant communication.

[8.4. Case in which the PDU session establishment procedure for establishing the second PDU session is immediately executed after the PDU session establishment procedure for establishing the first PDU session is executed]
Each device establishes the first PDU session by executing the procedure in Chapter 8.2, and immediately after that, establishes the second PDU session by executing the procedure in Chapter 8.3 and establishes redundant communication. It can be carried out. However, in some cases, such as when the device is congested, each device may not be able to immediately establish the second PDU session after establishing the first PDU session. In this chapter, such cases are explained by dividing them into four cases.

[8.4.1. Case 1]
Case 1 is a case where the establishment of the second PDU session is restricted in the PDU session establishment procedure of Chapter 8.2 that is executed to establish the first PDU session.

Specifically, the UE_10 sends a PDU session establishment request message to the SMF_220 in the PDU session establishment procedure of Chapter 8.2, and the SMF_220 establishes a PDU session establishment including at least one of the 40th to 41st identification information. This is a case where the UE_12 restricts the establishment of the second PDU session by receiving the acceptance message.

That is, UE_10, in the PDU session establishment procedure of Chapter 8.2, if the PDU session establishment acceptance message including at least one of the identification information of the 40th to 41st, UE_12 is indicated by the 41st identification information. The PDU session establishment procedure in section 8.3 cannot be performed until the time period expires (timer expires). Then, the UE_12 becomes able to execute the PDU session establishment procedure in Chapter 8.3 after the period indicated by the 41st identification information has elapsed (the timer has expired). In other words, the UE_10 that received the timer value included in the PDU session establishment acceptance message of Chapter 8.2 transfers the timer value to UE_12, and the UE_12 uses that timer as a timer to limit the execution of the PDU session establishment procedure of Chapter 8.3. After setting the timer value, UE_12 can start the procedure for establishing the second PDU session (the PDU session establishment procedure in Chapter 8.3) after the set timer expires.

When UE_10 receives the timer value included in the PDU session establishment acceptance message in Chapter 8.2, it transfers it to the storage unit or control unit of the device so that UE_10 and UE_12 are managed by the same timer. You can Also, UE_10, when receiving the timer value included in the PDU session establishment acceptance message of Chapter 8.2, in UE_10, set the timer value as a timer to limit the execution of the PDU session establishment procedure of Chapter 8.3, the timer The establishment of the second PDU session by UE_12 may be restricted until the time expires. Further, UE_10, when receiving the timer value included in the PDU session establishment acceptance message of Chapter 8.2, transfers the timer value to UE_12, in UE_12, as a timer for limiting the execution of the PDU session establishment procedure of Chapter 8.3. , The timer value may be set, and the establishment of the second PDU session by UE_12 may be restricted until the timer expires.

[8.4.2. Case 2]
Case 2, like Case 1, is a case where the establishment of the second PDU session is restricted in the PDU session establishment procedure of Chapter 8.2 executed to establish the first PDU session.

That is, UE_10, in the PDU session establishment procedure of Chapter 8.2, if the PDU session establishment acceptance message including at least one of the identification information of the 40th to 41st, UE_12 is indicated by the 41st identification information. The PDU session establishment procedure in section 8.3 cannot be performed until the time period expires (timer expires). Up to this point, it is similar to Case 1.

However, after the PDU session establishment procedure in section 8.2 is completed and before the period indicated by the 41st identification information has elapsed (timer has expired), the core network side sends a PDU session change command message to allow UE_12 Can be set so that the PDU session establishment procedure in Chapter 8.3 can be executed before the period indicated by the 41st identification information elapses (the timer expires), or the period indicated by the 41st identification information. It can also be set to extend or shorten (the period during which the PDU session establishment procedure in Chapter 8.3 cannot be performed).

After the PDU session establishment procedure in Chapter 8.2 is completed, UE_12 is still executing the PDU session establishment procedure in Chapter 4.3 even after the period indicated by the 41st identification information has elapsed (timer has expired). When not present, the PDU session change command message may be sent from the core network side to reset the period indicated by the 41st identification information (the period during which the PDU session establishment procedure in Chapter 4.3 cannot be executed).

Furthermore, in the PDU session establishment procedure of Chapter 8.2, if UE_10 receives a PDU session establishment acceptance message containing at least the 40th identification information, UE_12 sends PDU session change command message from the core network side to 8.3. The PDU session establishment procedure in Chapter 8.3 can be configured to be executed, or the PDU session establishment procedure in Chapter 8.3 can be started. In this case, the PDU session establishment acceptance message may not include the 41st identification information.

Specifically, UE_10 receives the PDU session change command message including at least one of the 61st to 62nd identification information items from the SMF_220 after the PDU session establishment procedure in section 4.2 is completed, and thus UE_12 It is possible to change the timing to start the procedure for establishing the second PDU session by the.

If the 61st identification information is the information indicating the PDU session ID for identifying the PDU session established as the second PDU session, the 62nd identification information is the revalidation of the PDU session. May be the information indicating the request, specifically, the 39th 5GSM reason value (5GSM cause) or the information indicating the reactivation request. When the 61st identification information is information indicating a PDU session ID for identifying the PDU session established as the second PDU session, the PDU session change command message further identifies UE_12. It may include information.

For example, if the timer value indicated by the 41st identification information is 0, UE_12 sets the timer value as a timer that restricts the execution of the PDU session establishment procedure in section 4.3, and the set timer expires. Then the PDU session establishment procedure in section 4.3 can be performed.

If the timer value indicated by the 41st identification information is a value other than 0, UE_12 sets the timer value as a timer that restricts the execution of the PDU session establishment procedure in Chapter 4.3, and the set value is set. You can wait until the timer expires and after that expire the PDU session establishment procedure in section 4.3.

[8.4.3. Case 3]
Next, Case 3 differs from Cases 1 and 2 in that the establishment of the second PDU session is part of the PDU session establishment procedure in Section 8.3 executed by UE_12 to establish the second PDU session. This is a limited case.

Specifically, after completing the PDU session establishment procedure in Chapter 8.2, UE_12 executed the PDU session establishment procedure in Chapter 8.3. This is a case where establishment is restricted. More specifically, the UE_12, in the PDU session establishment procedure of Chapter 8.3, when transmitting a PDU session establishment request message to SMF_222, from SMF_222, a PDU session including at least one of the 51st to 52nd identification information. This is a case where the establishment of the second PDU session is restricted by receiving the establishment rejection message.

That is, in the PDU session establishment procedure of chapter 8.3 executed by UE_12 at any timing after the PDU session establishment procedure of Chapter 8.2 is completed and the first PDU session is established, UE_12 is When a PDU session establishment rejection message containing at least one of the identification information is received, the PDU session establishment procedure in Chapter 8.3 is executed again until the period indicated by the 52nd identification information elapses (timer expires). Can not do it. Then, after the period indicated by the 52nd identification information has passed (the timer has expired), UE_12 can execute the PDU session establishment procedure in Chapter 8.3 again. In other words, the UE_12 that received the timer value contained in the PDU session establishment rejection message in Chapter 8.3 from SMF_222 sets the timer value again as a timer that restricts the execution of the PDU session establishment procedure in Chapter 8.3, and then sets it. After the timer expires, the procedure for establishing the second PDU session (section 8.3 PDU session establishment procedure) can be started. That is, UE_12 can send the PDU session establishment request message again to SMF_222 after this timer expires.

[8.4.4. Case 4]
Case 4, like Case 3, is a case where the establishment of the second PDU session is restricted in the PDU session establishment procedure of Chapter 8.3 executed by the UE_12 to establish the second PDU session.

Specifically, after completing the PDU session establishment procedure in Chapter 8.2, UE_12 executed the PDU session establishment procedure in Chapter 8.3. This is a case where establishment is restricted. More specifically, UE_12, in the PDU session establishment procedure of chapter 8.3, when transmitting a PDU session establishment request message to SMF_222, from SMF_222, a PDU session including at least one of the 40th to 41st identification information. This is a case where the establishment of the second PDU session is restricted by receiving the establishment permission message.

Note that UE_12 has received the PDU session establishment permission message in the PDU session establishment procedure in Section 4.3 that is executed to establish the second PDU session, so this procedure itself succeeds (completes normally). However, the second PDU session may not be established. Here, "unable to establish a second PDU session" may mean "a second PDU session is established, but this PDU session cannot be used". Further, "unable to establish a second PDU session" may mean "UE_12 cannot establish PDU session", or "UE_12 cannot use PDU session". May mean

In other words, in the PDU session establishment procedure of Chapter 8.3 executed by UE_12 at any timing after the PDU session establishment procedure of Chapter 8.2 is completed and the first PDU session is established, UE_12 is When the PDU session establishment acceptance message including at least one of the identification information is received, the second PDU session cannot be established until the period indicated by the 41st identification information elapses (timer expires). .. Then, the UE_12 becomes able to establish the second PDU session after the period indicated by the 41st identification information has elapsed (the timer has expired). Here, "the second PDU session can be established" may mean "the second PDU session was established, but this PDU session can be used". Furthermore, "the second PDU session can be established" may mean "UE_12 can establish a PDU session", or "UE_12 can establish the established PDU session." Can be used ”.

In other words, the UE_12 that received the timer value included in the PDU session establishment acceptance message in Chapter 8.3 sets the timer value as a timer that limits the establishment of the second PDU session, and the set timer expires. At times, a second PDU session can be established.

However, UE_12, after receiving the PDU session establishment acceptance message, before the period indicated by the 41st identification information elapses (timer expires), by transmitting the PDU session change command message from the core network side, UE_12 can also be set so that a second PDU session can be established before the period indicated by the 41st identification information has elapsed (the timer has expired), and is indicated by the 41st identification information. It is also possible to set to extend or shorten the period during which the second PDU session cannot be established.

Also, after receiving the PDU session establishment acceptance message, even after the period indicated by the 41st identification information has elapsed (timer has expired), if UE_12 has not established a second PDU session, By transmitting the PDU session change command message from the core network side, the period indicated by the 41st identification information (the period during which the second PDU session cannot be established) can be reset.

Furthermore, UE_12, in the PDU session establishment procedure of chapter 8.3, when receiving a PDU session establishment acceptance message including at least 40th identification information, by sending a PDU session change command message from the core network side, UE_12, It can be set so that the second PDU session can be established, and communication using the second PDU session can be executed. In this case, the PDU session establishment acceptance message may not include the 41st identification information.

Specifically, the UE_12 establishes the second PDU session by receiving the PDU session change command message including the identification information from 61st to 62nd from the SMF_222 after completing the PDU session establishment procedure in Chapter 8.3. You can change the timing.

Note that the 61st identification information is preferably information indicating a PDU session ID for identifying the PDU session established as the second PDU session. Further, when the 61st identification information is information indicating a PDU session ID for identifying a PDU session established as a second PDU session, the PDU session change command message further identifies UE_12. It may include information.

The 62nd identification information is information indicating that the establishment of the second PDU session is permitted, and / or information indicating that the establishment of the second PDU session is possible, and It may be the information indicating that the communication using the second PDU session is permitted and / or the information indicating that the communication using the second PDU session is enabled. , PDU session reactivation request information may be, specifically, the 39th 5GSM reason value (5GSM cause), may be a reactivation request (reactivation request) information May be

For example, if the timer value indicated by the 41st identification information is 0, UE_12 sets the timer value as a timer that limits the establishment of the second PDU session, and after the set timer expires. , A second PDU session can be established.

If the timer value indicated by the 41st identification information is a value other than 0, UE_12 sets the timer value as a timer that limits the establishment of the second PDU session, and the set timer is Wait until it expires, and after that timer expires, a second PDU session can be established.

[9. Sixth Embodiment]
Next, a sixth embodiment will be described. Here, the sixth embodiment is also referred to as the present embodiment. In the present embodiment, as in the fifth embodiment, a certain device has two independent UEs, and each UE establishes a PDU session, thereby enabling redundant communication. Different from the first to fourth embodiments up to.

In this chapter, "Registration procedure" in Chapter 9.1, "PDU session establishment procedure for establishing the first PDU session" in Chapter 9.2, "PDU session establishment procedure for establishing the second PDU session" in Chapter 9.3 , Section 9.4, "Case of not performing the PDU session establishment procedure that establishes the second PDU session immediately after executing the PDU session establishment procedure that establishes the first PDU session", Chapter 9.5 The procedure for changing the PDU session anchor that provides the second PDU session of SSC mode 3 "will be described in this order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in Section 9.1. This procedure is performed by UE_10 and UE_12.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Chapter 9.2, and performs communication using the first PDU session between UE_10 and DN. Transition to a state where

Next, each device establishes a second PDU session by executing the PDU session establishment procedure described in Chapter 9.3, and performs communication using the second PDU session between UE_12 and DN. Transition to a state in which it is possible. At this time, the device can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state in which redundant communication is possible.

Next, a case where each device restricts the PDU session establishment procedure that establishes the second PDU session immediately after performing the PDU session establishment procedure described in Chapter 9.2 will be explained in Chapter 9.4. ..

Finally, when each device executes the procedure described in Chapter 9.5 and the SSC mode of the second PDU session is SSC mode 3, the PDU session anchor that provides the PDU session of SSC mode 3 is changed. By establishing the third (new) PDU session by executing the procedure and then releasing the second (existing) PDU session, the PDU session anchor (that is, UPF) is maintained while continuing the session. Explain the procedure to change.

[9.1. Registration procedure]
The registration procedure in the present embodiment may be the same as the registration procedure in the fifth embodiment (registration procedure in section 8.1), so description thereof will be omitted. Each device (especially UE_10 and AMF_210) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure. Further, each device (especially UE_12 and AMF_212) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure.

[9.2. PDU session establishment procedure for establishing the first PDU session]
Next, an outline of a PDU session establishment procedure to establish a PDU session for a DN will be described with reference to FIG. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in Chapter 8.2, but the identification information contained in the PDU session establishment request message and / or NAS message and the identification information contained in the PDU session establishment acceptance message are Different from Chapter 8.2. However, since there are many points in common with the explanation in Chapter 8.2, the explanation of the common points will be omitted, and the different points will be mainly explained below. The UE, gNB_110, AMF_210, SMF_220, and UPF_230 are the same as in Chapter 8.2.

First, UE_10 can send at least one of the 21st, 23rd, 26th, and 28th identification information in the PDU session establishment request message and / or NAS message. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Furthermore, the contents indicated by the 21st, 23rd to 26th, 28th identification information may be as described above, but the SSC mode indicated by the 23rd identification information may be SSC mode 1 or SSC mode 2. You can use SSC mode3. Furthermore, it is preferable that the DNN indicated by the 25th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Chapter 9.1. Furthermore, the S-NSSAI indicated by the 26th identification information is preferably the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Chapter 9.1.

When SMF_220 receives the PDU session establishment request message, SMF_220 can recognize that UE_10 is requesting and / or various identification information included in the PDU session establishment request message.

Also, SMF_222 and / or AMF_210 can include at least one of the 31st, 33rd to 36th, and 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st, 33rd to 36th, and 38th identification information may be as described above, but the SSC mode indicated by the 33rd identification information may be SSC mode 1 or SSC mode 2. However, it may be SSC mode3.

Furthermore, the content indicated by the 35th identification information may be the same as or different from the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Further, it is preferable that the DNN indicated by the 35th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Chapter 9.1. Furthermore, the content indicated by the 36th identification information may be the same as or different from the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Furthermore, the S-NSSAI indicated by the 36th identification information is preferably the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Chapter 9.1.

[9.3. PDU session establishment procedure for establishing the second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in Chapter 8.3, but the identification information included in the PDU session establishment request message and / or the NAS message and the identification information included in the PDU session establishment acceptance message are Different from Chapter 8.3. However, since there are many points in common with the explanation in Chapter 8.3, the explanation of the common points will be omitted and the different points will be mainly explained below. Each device related to this procedure is UE_12, gNB_112, AMF_212, SMF_222, UPF_232, DN_300, which is the same as in Chapter 8.3.

First, UE_12 can include at least one of the identification information of the third, 13, 21, 23 to 28 in the PDU session establishment request message and / or the NAS message and transmit it. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the content indicated by the identification information of the third, 13, 21, 23 to 28 may be as described above, but the content indicated by the 23rd identification information is included in the PDU session establishment acceptance message of Chapter 9.2. It is preferable that the content is the same as the content indicated by the 33rd identification information. Further, it is preferable that the content indicated by the 24th identification information is the same as the content indicated by the 34th identification information included in the PDU session establishment acceptance message in Chapter 9.2.

Also, the content indicated by the 25th identification information is preferably the same as the content indicated by the 35th identification information included in the PDU session establishment acceptance message in Chapter 9.2. Furthermore, it is preferable that the DNN indicated by the 25th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Chapter 9.1. Also, the content indicated by the 26th identification information is preferably the same as the content indicated by the 36th identification information included in the PDU session establishment acceptance message in Chapter 9.2. Furthermore, the S-NSSAI indicated by the 26th identification information is preferably the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Chapter 9.1.

Further, the content indicated by the 27th identification information is preferably the same as the content indicated by the 28th identification information included in the PDU session establishment request message in Chapter 9.2, and the PDU session establishment acceptance message in Chapter 9.2. It is preferable that the content is the same as the content indicated by the 38th identification information included in. Further, the content indicated by the 28th identification information is preferably different from the content indicated by the 28th identification information included in the PDU session establishment request message of Chapter 9.2, and is included in the PDU session establishment acceptance message of Chapter 9.2. It is preferable that the content is different from the content indicated by the 38th identification information. The 27th identification information may be transmitted in association with the 3rd identification information and / or the 13th identification information. Further, the 27th identification information is transmitted by being associated with the third identification information and / or the 13th identification information, so that the PDU session ID indicated by the 27th identification information is one that UE_10 has established. May be indicated.

Also, SMF_222 and / or AMF_212 can include at least one of the identification information of the third, 13, 31, 33 to 38 in the PDU session establishment acceptance message and transmit it. Here, the contents indicated by the third, 13, 31, 33 to 38 identification information may be as described above, but the contents indicated by the 33rd identification information are included in the PDU session establishment request message of this chapter. The content may be the same as or different from the content indicated by the 23rd identification information. The content indicated by the 34th identification information may be the same as or different from the content indicated by the 24th identification information included in the PDU session establishment request message of this chapter.

The content indicated by the 35th identification information may be the same as or different from the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Further, it is preferable that the DNN indicated by the 35th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Chapter 9.1. The content indicated by the 36th identification information may be the same as or different from the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Furthermore, the S-NSSAI indicated by the 36th identification information is preferably the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Chapter 9.1.

The content indicated by the 37th identification information may be the same as or different from the content indicated by the 27th identification information included in the PDU session establishment request message of this chapter. The content indicated by the 38th identification information may be the same as or different from the content indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Also, the PDU session ID shown in the 38th identification information is preferably different from the PDU session ID shown in the 28th identification information included in the PDU session establishment request message in Chapter 9.2, and the PDU session in Chapter 9.2 It is preferable that it is different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message, and the same as the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Is preferred, but may be different. The 37th identification information may be transmitted in association with the 3rd identification information and / or the 13th identification information. Further, the 37th identification information, the third identification information, and / or by being transmitted in association with the 13th identification information, the PDU session ID indicated by the 37th identification information is the one established by UE_10. May be indicated. The SMF_222 and / or the AMF_212 can notify the UE_12 of the content of the identification information by transmitting at least one of the identification information. Note that SMF_222 and / or AMF_212 may indicate that the network supports each function or may indicate that the request of UE_12 has been accepted, by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

The above is the difference between this procedure and the procedure in Chapter 8.3. For the parts not described in this chapter, the description in Chapter 8.3 can be applied.

[9.4. Case in which the PDU session establishment procedure that establishes the second PDU session is immediately executed after the PDU session establishment procedure that establishes the first PDU session is executed]
Since this case in the present embodiment may be the same as the description in Chapter 8.4 in the fifth embodiment, the description thereof will be omitted.

[9.5. Procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3]
Then, by executing the PDU session establishment procedure in Chapter 9.3, if the second PDU session is established and the SSC mode of the PDU session is SSC mode 3, the PDU session is provided. A PDU session anchor (PSA) change procedure to be performed will be described with reference to FIG. This procedure is triggered by the network (SMF) and after establishing a new PDU session for the same DN using the new PDU session anchor, the existing (old) PDU associated with the old PDU session anchor is This is a procedure for releasing a session. Note that the AMF is not changed by this procedure, but the SMF may be changed.

UE_12 uses the second PDU session to send and receive user data. Specifically, the UE_12 is transmitting / receiving the uplink data and / or the downlink data to / from the DN_300 via the UPF_232 (S1100).

When SMF_222 determines that UPF and / or SMF needs to be changed (S1102), SMF_222 informs AMF_212 of a PDU session change command message including at least one of the 61st to 62th identification information. Sends N1 SM (Session Management) container including S1104 (S1104). The N1SM container may be a NAS message. Further, the NAS message may be a downlink NAS transport (DL NAS transport) message. Here, the contents indicated by the 61st to 62nd identification information may be as described above, but the 61st identification information is the PDU session ID for identifying the PDU session established as the second PDU session. The 62nd identification information may be information indicating that a PDU session for the same DN needs to be reestablished.

AMF_212 transfers the NAS message received from SMF_222 to UE_12 (S1106).

UE_12, upon receiving the NAS message, may decide to start the PDU session establishment procedure for the same DN (S1108). UE_12, by receiving the PDU session change command message, to establish a new PDU session, is required to release the old PDU session, and / or of each identification information included in the PDU session change command message. Can recognize the contents. This PDU session establishment procedure is basically the same as the PDU session establishment procedure in Chapter 9.3, but it is necessary to replace SMF_222 with SMF_224 and UPF_232 with UPF_234. Also, the identification information included in the PDU session establishment request message and / or the NAS message and the identification information included in the PDU session establishment acceptance message are different from those in Chapter 9.3. However, since there are many points in common with the explanation in Chapter 9.3, explanations of common points are omitted, and in the following, different points will be mainly described. UE_12, gNB_112, AMF_212, and DN are the same as in Chapter 9.3.

First, UE_12 starts a PDU session establishment procedure by transmitting a NAS message including a PDU session establishment request message to SMF_224 via 5GAN and AMF_212 (S900) (S902) (S904). Specifically, when the UE_12 transmits a NAS message including a PDU session establishment request message to the gNB_112 (S900), the gNB_112 transfers it to the AMF_212 via the N2 interface.

Here, UE_12, PDU session establishment request message and / or NAS message, at least one of the identification information of the third, 13, 21, 23 to 29 can be transmitted, but with these It may be included in a different control message, for example, a control message of a layer lower than the NAS layer (eg, RRC layer, MAC layer, RLC layer, PDCP layer) and transmitted. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Furthermore, the content indicated by the identification information of the third, 13, 21, 23 to 29 may be as described above, but the content indicated by the 23rd identification information is included in the PDU session establishment acceptance message of Chapter 9.3. It is preferable that the contents are the same as the contents indicated by the 33rd identification information contained in the PDU session establishment request message in Chapter 9.3 and / or the 23rd identification information contained in 9.3. Further, the content indicated by the 24th identification information is the 34th identification information included in the PDU session establishment acceptance message in Chapter 9.3, and / or the 24th identification information included in the PDU session establishment request message in Chapter 9.3. It is preferably the same as the content shown. Further, the content indicated by the 25th identification information is the 35th identification information included in the PDU session establishment acceptance message in Chapter 9.3, and / or the 25th identification information included in the PDU session establishment request message in Chapter 9.3. It is preferably the same as the content shown. Further, the content indicated by the 26th identification information is the 36th identification information included in the PDU session establishment acceptance message of Chapter 9.3 and / or the 36th identification information included in the PDU session establishment request message of Chapter 9.3. It is preferably the same as the content shown.

Also, it is preferable that the PDU session ID indicated by the 27th identification information indicates the PDU session ID established by the PDU session establishment procedure in Chapter 9.2. The PDU session ID indicated by the 28th identification information is preferably different from the PDU session ID indicated by the 27th identification information in this chapter, and different from the PDU session ID indicated by the 29th identification information in this chapter. Preferably. Also, the PDU session ID indicated by the 28th identification information may indicate a newly established PDU session ID. Further, it is preferable that the PDU session ID indicated by the 29th identification information indicates the PDU session ID established by the PDU session establishment procedure in Chapter 9.3. The 27th identification information may be transmitted in association with the 3rd identification information and / or the 13th identification information. Further, the 27th identification information is transmitted by being associated with the third identification information and / or the 13th identification information, so that the PDU session ID indicated by the 27th identification information is one that UE_10 has established. May be indicated. UE_12 can notify the network of the content of these identification information by transmitting these identification information. These pieces of identification information may be included in these messages to indicate the request of the UE_12. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information.

Further, when the AMF_212 receives the PDU session establishment request message, it selects SMF_224 as its transfer destination (S902) and transfers the PDU session establishment request message to SMF_224 via the N11 interface (S904).

Further, when the SMF_224 receives the PDU session establishment request message from the AMF_212 (S904), the SMF_224 can recognize that the UE_12 makes a request and various identification information included in the PDU session establishment request message.

When SMF_224 receives the session establishment response message from UPF_234, SMF_224 may perform the address assignment of the address assigned to UE_12. The SMF_224 sends a PDU session establishment acceptance message to the UE_12 via the AMF_212 (S910) (S912). Specifically, SMF_224 transmits a PDU session establishment acceptance message to AMF_212 via the N11 interface (S910), and upon receiving this, AMF_212 includes a PDU session establishment acceptance message in UE_12 via the N1 interface. Send a NAS message (S912). Specifically, when the AMF_212 transmits the PDU session establishment acceptance message to the gNB_112 via the N2 interface, the gNB_112 transmits the NAS message including the PDU session establishment acceptance message to the UE_12.

Here, SMF_224 and / or AMF_212 may include at least one of the identification information of the third, 13, 31, 33 to 39 in the PDU session establishment acceptance message and may transmit it. Here, the contents indicated by the third, 13, 31, 33 to 39 identification information may be as described above, but the contents indicated by the 33rd identification information are included in the PDU session establishment request message of this chapter. The content may be the same as the content indicated by the 23rd identification information. Also, the content indicated by the 34th identification information may be the same as the content indicated by the 24th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 35th identification information may be the same as the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Further, the content indicated by the 36th identification information may be the same as the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 37th identification information may be the same as the content indicated by the 27th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 38th identification information may be the same as the content indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Also, the content indicated by the 39th identification information may be the same as the content indicated by the 29th identification information included in the PDU session establishment request message of this chapter. The 37th identification information may be transmitted in association with the 3rd identification information and / or the 13th identification information. Further, the 37th identification information, the third identification information, and / or by being transmitted in association with the 13th identification information, the PDU session ID indicated by the 37th identification information is the one established by UE_10. May be indicated. SMF_224 and / or AMF_212 can notify UE_12 of the content of these identification information by transmitting these identification information. Note that SMF_224 and / or AMF_212 may indicate that the network supports each function or may indicate that the request of UE_12 has been accepted by transmitting these pieces of identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

The above is the difference between this procedure and the procedure in Chapter 9.3. For the parts not mentioned in this chapter, the description in Chapter 9.3 can be applied.

A new PDU session for redundant communication can be established as described above. That is, when this procedure is completed, UE_12 can transmit and receive uplink data and / or downlink data via UPF_234 that is a new UPF (S1110). In other words, the device uses the PDU session established by the PDU session establishment procedure of Chapter 9.2, the PDU session established by the PDU session establishment procedure of Chapter 9.3, and the PDU session established by the procedure of this chapter, Redundant communication can be performed.

Then, after the new PDU session is established, each device executes the PDU session release procedure (S1112) to release the old PDU session (the PDU session established by the PDU session establishment procedure in Chapter 9.3). it can. The PDU session release procedure may be started by the expiration of the timer in UE_12 or the expiration of the timer in SMF_222.

By the above, the PDU session anchor for performing redundant communication can be changed from UPF_232 to UPF_234. That is, the device_20 can perform redundant communication using the PDU session established by the procedure of this chapter and the PDU session established by the procedure of this chapter.

[10. Seventh Embodiment]
Next, a seventh embodiment will be described. Here, the seventh embodiment is also referred to as the present embodiment. In the present embodiment, as in the fifth to sixth embodiments, a device includes two independent UEs, and each UE establishes a PDU session, thereby enabling redundant communication. , Different from the first to fourth embodiments.

In this chapter, "Registration procedure" in Chapter 10.1, "PDU session establishment procedure for establishing the first PDU session" in Chapter 10.2, "PDU session establishment procedure for establishing the second PDU session" in Chapter 10.3 , Section 10.4, "Case to prevent the PDU session establishment procedure to establish the second PDU session immediately after executing the PDU session establishment procedure to establish the first PDU session", Section 10.5 The procedure for changing the PDU session anchor that provides the second PDU session of SSC mode 3 "will be described in this order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in Chapter 10.1. This procedure is performed by UE_10 and UE_12.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Section 10.2, and performs communication using the first PDU session between UE_10 and DN. Transition to a state where

Next, each device establishes a second PDU session by performing the PDU session establishment procedure described in Section 10.3, and performs communication using the second PDU session between UE_12 and DN. Transition to a state in which it is possible. At this time, the device can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state in which redundant communication is possible.

Next, Section 10.4 describes a case where each device performs the PDU session establishment procedure described in Section 10.2 and then restricts the PDU session establishment procedure that immediately establishes the second PDU session so that it cannot execute the PDU session establishment procedure. ..

Finally, when each device executes the procedure described in Chapter 10.5 and the SSC mode of the second PDU session is SSC mode 3, the PDU session anchor that provides the PDU session of SSC mode 3 is changed. By establishing the third (new) PDU session by executing the procedure and then releasing the second (existing) PDU session, the PDU session anchor (that is, UPF) is maintained while continuing the session. Explain the procedure to change.

[10.1. Registration procedure]
The registration procedure according to the present embodiment may be the same as the registration procedure according to the sixth embodiment (registration procedure in Chapter 9.1), and the description thereof will be omitted. Each device (especially UE_10 and AMF_210) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure. Further, each device (especially UE_12 and AMF_212) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure.

[10.2. PDU session establishment procedure for establishing the first PDU session]
The PDU session establishment procedure for establishing the first PDU session in the present embodiment, the PDU session establishment procedure for establishing the first PDU session in the sixth embodiment (the PDU session establishment procedure in Chapter 9.2) and Since they may be the same, the description thereof will be omitted. Upon completion of this procedure, each device may be in a state where the first PDU session for the DN is established.

[10.3. PDU session establishment procedure for establishing second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in Chapter 9.3, but the identification information included in the PDU session establishment request message and / or NAS message and the identification information included in the PDU session establishment acceptance message are Different from Chapter 9.3. However, since there are many points in common with the explanation in Chapter 9.3, explanations of common points are omitted, and in the following, different points will be mainly described. Each device related to this procedure is UE_12, gNB_112, AMF_212, SMF_222, UPF_232, DN_300, which is the same as in Chapter 9.3.

First, UE_12 can send at least one of the 21st, 23rd, 26th, and 28th identification information in the PDU session establishment request message and / or NAS message. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st, 23rd to 26th, and 28th identification information may be as described above, but the contents indicated by the 23rd identification information are the contents included in the PDU session establishment acceptance message of Chapter 10.2. It is preferable that the content is different from the content indicated by the identification information 33. Further, it is preferable that the content indicated by the 24th identification information is different from the content indicated by the 34th identification information included in the PDU session establishment acceptance message in Chapter 10.2.

Also, the content indicated by the 25th identification information is preferably different from the content indicated by the 35th identification information included in the PDU session establishment acceptance message in Chapter 10.2. Furthermore, the DNN indicated by the 25th identification information is preferably the DNN indicated by the 14th identification information included in the registration acceptance message in Chapter 10.1. Further, the content indicated by the 26th identification information is preferably different from the content indicated by the 36th identification information included in the PDU session establishment acceptance message in Chapter 10.2. Furthermore, it is preferable that the S-NSSAI indicated by the 26th identification information is the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Chapter 10.1.

Further, the content indicated by the 28th identification information is preferably different from the content indicated by the 28th identification information included in the PDU session establishment request message of Chapter 10.2, and is included in the PDU session establishment acceptance message of 10.2. It is preferable that the contents are different from the contents shown by the 38th identification information.

Also, SMF_222 and / or AMF_212 can include at least one of the 31st, 33rd to 36th, and 38th identification information in the PDU session establishment acceptance message and can transmit it. Here, the contents indicated by the 31st, 33rd to 36th and the 38th identification information may be as described above, but the contents indicated by the 33rd identification information are the contents included in the PDU session establishment request message of this chapter. It may be the same as or different from the content indicated by the 23 pieces of identification information. The content indicated by the 34th identification information may be the same as or different from the content indicated by the 24th identification information included in the PDU session establishment request message of this chapter.

The content indicated by the 35th identification information may be the same as or different from the content indicated by the 25th identification information included in the PDU session establishment request message of this chapter. Further, it is preferable that the DNN indicated by the 35th identification information is the DNN indicated by the 14th identification information included in the registration acceptance message in Chapter 10.1. The content indicated by the 36th identification information may be the same as or different from the content indicated by the 26th identification information included in the PDU session establishment request message of this chapter. Furthermore, it is preferable that the S-NSSAI indicated by the 36th identification information is the S-NSSAI indicated by the 15th identification information included in the registration acceptance message in Chapter 10.1.

The content indicated by the 38th identification information may be the same as or different from the content indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Further, the PDU session ID shown in the 38th identification information is preferably different from the PDU session ID shown in the 28th identification information included in the PDU session establishment request message in Chapter 10.2, and the PDU session in Chapter 10.2 It is preferable that it is different from the PDU session ID indicated by the 38th identification information included in the establishment acceptance message, and the same as the PDU session ID indicated by the 28th identification information included in the PDU session establishment request message of this chapter. Is preferred, but may be different. The SMF_222 and / or the AMF_212 can notify the UE_12 of the content of the identification information by transmitting at least one of the identification information. Note that SMF_222 and / or AMF_212 may indicate that the network supports each function or may indicate that the request of UE_12 has been accepted, by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

[10.4. Case where the PDU session establishment procedure for establishing the second PDU session is immediately executed after the PDU session establishment procedure for establishing the first PDU session is executed]
This case in the present embodiment may be the same as the description in Chapter 9.4 in the sixth embodiment, and therefore its description is omitted.

[10.5. Procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3]
The “procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3” in the present embodiment is “change the PDU session anchor that provides the second PDU session in SSC mode 3” in the sixth embodiment. Since it may be the same as the “procedure” (procedure in Chapter 9.5), its explanation is omitted.

[11. Eighth Embodiment]
Next, an eighth embodiment will be described. Here, the eighth embodiment is also referred to as the present embodiment. In the present embodiment, as in the fifth to seventh embodiments, a device has two independent UEs, and each UE establishes a PDU session, thereby enabling redundant communication. , Different from the first to fourth embodiments.

In this chapter, "Registration procedure" in Chapter 11.1, "PDU session establishment procedure for establishing the first PDU session" in Chapter 11.2, "PDU session establishment procedure for establishing the second PDU session" in Chapter 11.3 , Section 11.4, "Case to prevent the PDU session establishment procedure to establish the second PDU session immediately after executing the PDU session establishment procedure to establish the first PDU session", Section 11.5 The procedure for changing the PDU session anchor that provides the second PDU session of SSC mode 3 "will be described in this order.

First, each device transitions to the state where the UE is registered in the network by executing the registration procedure described in section 11.1. This procedure is performed by UE_10 and UE_12.

After that, each device establishes the first PDU session by executing the PDU session establishment procedure described in Section 11.2, and performs communication using the first PDU session between UE_10 and DN. Transition to a state where

Next, each device establishes a second PDU session by executing the PDU session establishment procedure described in Section 11.3, and performs communication using the second PDU session between UE_12 and DN. Transition to a state in which it is possible. At this time, the device can transmit and receive the user data using the first PDU session and the second PDU session, and thus it can be said that each device is in a state in which redundant communication is possible.

Next, Section 11.4 describes the case where each device restricts the PDU session establishment procedure that establishes the second PDU session immediately after performing the PDU session establishment procedure described in Section 11.2. .

Finally, when each device executes the procedure described in Chapter 11.5 and the SSC mode of the second PDU session is SSC mode 3, the PDU session anchor that provides the PDU session of SSC mode 3 is changed. By establishing the third (new) PDU session by executing the procedure and then releasing the second (existing) PDU session, the PDU session anchor (that is, UPF) is maintained while continuing the session. Explain the procedure to change.

[11.1. Registration procedure]
The registration procedure in this embodiment may be the same as the registration procedure in the seventh embodiment (registration procedure in Chapter 10.1), and therefore its description is omitted. Each device (especially UE_10 and AMF_210) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure. Further, each device (especially UE_12 and AMF_212) can transit to the registration state (RM-REGISTERED state) based on the completion of the registration procedure.

[11.2. PDU session establishment procedure for establishing the first PDU session]
The PDU session establishment procedure for establishing the first PDU session in the present embodiment is a PDU session establishment procedure for establishing the first PDU session in the seventh embodiment (the PDU session establishment procedure in 10.2) and Since they may be the same, the description thereof will be omitted. Upon completion of this procedure, each device may be in a state where the first PDU session for the DN is established.

[11.3. PDU session establishment procedure for establishing the second PDU session]
Next, each device executes a PDU session establishment procedure to establish a second PDU session for the same DN as the established first PDU session. Here, this PDU session establishment procedure is also referred to as this procedure. This procedure is basically the same as the PDU session establishment procedure in section 10.3, but the identification information contained in the PDU session establishment request message and / or the NAS message and the identification information contained in the PDU session establishment acceptance message are Different from 10.3 However, since there are many points in common with the description in Chapter 10.3, the description of the common points will be omitted, and the different points will be mainly described below. Note that the devices related to this procedure are UE_12, gNB_112, AMF_212, SMF_222, UPF_232, and DN_300, which are the same as in Section 10.3.

First, the UE can transmit at least one of the identification information of the third, 13, 21, 23 to 28 in the PDU session establishment request message and / or the NAS message. Here, the NAS message may be an uplink NAS transport (UL NAS TRANSPORT) message. Further, the contents indicated by the 21st, 23rd to 26th, 28th identification information may be the same as in 10.3. Also, the content indicated by the 27th identification information may be the same as in Chapter 9.3. The 27th identification information may be transmitted in association with the 3rd identification information and / or the 13th identification information. Further, the 27th identification information is transmitted by being associated with the third identification information and / or the 13th identification information, so that the PDU session ID indicated by the 27th identification information is one that UE_10 has established. May be indicated.

Also, SMF_222 and / or AMF_212 can include at least one of the identification information of the third, 13, 31, 33 to 38 in the PDU session establishment acceptance message and transmit it. Here, the contents indicated by the 31st, 33rd to 36th, and 38th identification information may be the same as in Section 10.3. Also, the content indicated by the 37th identification information may be the same as in Chapter 9.3. The 37th identification information may be transmitted in association with the 3rd identification information and / or the 13th identification information. Further, the 37th identification information, the third identification information, and / or by being transmitted in association with the 13th identification information, the PDU session ID indicated by the 37th identification information is the one established by UE_10. May be indicated. The SMF_222 and / or the AMF_212 can notify the UE_12 of the content of the identification information by transmitting at least one of the identification information. Note that SMF_222 and / or AMF_212 may indicate that the network supports each function or may indicate that the request of UE_12 has been accepted, by transmitting these identification information. Further, two or more pieces of identification information of these pieces of identification information may be configured as one or more pieces of identification information. The information indicating the support of each function and the information indicating the request for use of each function may be transmitted / received as the same identification information or may be transmitted / received as different identification information.

The above is the difference between this procedure and the procedure in Chapter 10.3. For the parts not described in this chapter, the description in Chapter 10.3 can be applied.

[11.4. Case where the PDU session establishment procedure for establishing the second PDU session is immediately executed after the PDU session establishment procedure for establishing the first PDU session is executed]
Since this case in the present embodiment may be the same as the description in Chapter 10.4 in the seventh embodiment, the description thereof will be omitted.

[11.5. Procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3]
The “procedure for changing the PDU session anchor that provides the second PDU session in SSC mode 3” in the present embodiment is the “change the PDU session anchor that provides the second PDU session in SSC mode 3” in the seventh embodiment. Since it may be the same as the “procedure” (procedure in Section 10.5), its explanation is omitted.

[12. Modification]
The program that operates in the device related to the present invention may be a program that controls a Central Processing Unit (CPU) or the like to cause a computer to function so as to realize the functions of the embodiments related to the present invention. The program or information handled by the program is temporarily stored in a volatile memory such as a Random Access Memory (RAM) or a non-volatile memory such as a flash memory, a Hard Disk Drive (HDD), or another storage device system.

The program for realizing the functions of the embodiments according to the present invention may be recorded in a computer-readable recording medium. It may be realized by causing a computer system to read and execute the program recorded in this recording medium. The “computer system” here is a computer system built in the apparatus and includes an operating system and hardware such as peripheral devices. Further, the "computer-readable recording medium" is a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a medium that dynamically holds a program for a short time, or another computer-readable recording medium. Is also good.

Also, each functional block or various features of the device used in the above-described embodiments may be implemented or executed by an electric circuit, for example, an integrated circuit or a plurality of integrated circuits. Electrical circuits designed to perform the functions described herein are general purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or others. Programmable logic devices, discrete gate or transistor logic, discrete hardware components, or combinations thereof. A general purpose processor may be a microprocessor, conventional processor, controller, microcontroller, or state machine. The electric circuit described above may be composed of a digital circuit or an analog circuit. Further, in the event that an integrated circuit technology that replaces the current integrated circuit appears due to the progress of semiconductor technology, one or more aspects of the present invention can use a new integrated circuit according to the technology.

Note that the present invention is not limited to the above embodiment. Although one example of the device is described in the embodiment, the present invention is not limited to this, and a stationary or non-movable electronic device installed indoors or outdoors, such as an AV device or a kitchen device. It can be applied to terminal devices or communication devices such as cleaning / laundry equipment, air conditioning equipment, office equipment, vending machines, and other household appliances.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and includes design changes and the like within a range not departing from the gist of the present invention. The present invention can be modified in various ways within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Be done. Further, a configuration in which the elements described in each of the above embodiments and having the same effect are replaced with each other is also included.

Claims

A user device,
The user device includes a control unit and a transmission / reception unit,
The control unit executes a registration procedure,
In the registration procedure, the transceiver unit
Send a registration request message containing information identifying another user device,
Receive registration acceptance message including UE Reliability Group (UE RG), DNN (Data Network Name) for URLLC (Ultra-Reliable and Low Latency Communications), and S-NSSAI (Single Network Slice Selection Assistance Information) A user equipment characterized by the above.
The control unit executes a PDU (Protocol Data Unit) session establishment procedure for establishing a PDU session,
The transmitting / receiving unit is
In the PDU session establishment procedure, a PDU session establishment request message including information indicating that SSC (Session and Service Continuity) mode for a PDU session for URLLC is SSC mode 1,
2. The user equipment according to claim 1, wherein the PDU session is established based on reception of a PDU session establishment acceptance message as a response to the PDU session establishment request message.
The control unit executes a PDU session establishment procedure for establishing a PDU session,
The transmitting / receiving unit is
In the PDU session establishment procedure, for PDU session for URLLC, SSC mode, and / or PDU session type, and / or DNN, and / or S-NSSAI, and / or PDU session ID indicating the PDU session, and / Or, transmits a PDU session establishment request message including information identifying the other user equipment, and / or a second PDU session ID indicating a second PDU session established by the other user equipment,
2. The user equipment according to claim 1, wherein the PDU session is established based on reception of a PDU session establishment acceptance message as a response to the PDU session establishment request message.
When the SSC mode for the PDU session is SSC mode 3, when changing the PDU session anchor corresponding to the PDU session,
The transmission / reception unit receives a PDU session change command including a PDU session ID indicating the PDU session and a cause indicating a reason why the PDU session needs to be changed,
The control unit executes a second PDU session establishment procedure for establishing a second PDU session different from the PDU session,
The transmitter / receiver is applied to the PDU session in the second PDU session establishment procedure, SSC mode, and / or PDU session type, and / or DNN, and / or S-NSSAI, and / or Or, after transmitting a PDU session establishment request message including a PDU session ID indicating the PDU session, and / or a PDU session ID indicating the PDU session, and / or a PDU session ID indicating the second PDU session,
The control unit executes a PDU session release procedure for releasing the PDU session,
4. The user equipment according to claim 3, wherein the control unit changes a PDU session anchor corresponding to the PDU session.
The transceiver unit, in the PDU session establishment procedure, as a response to the PDU session establishment request message, a PDU session including a back-off timer value and 5GSM cause indicating that establishment of the PDU session is prohibited. When you receive the establishment rejection message,
The control unit sets the back-off timer value as a timer for limiting execution of the PDU session establishment procedure,
The transmitting / receiving unit is
Do not perform the PDU session establishment procedure again until the timer expires,
4. The user equipment according to claim 2 or 3, wherein after the timer expires, the PDU session establishment procedure is executed again.
The transceiver unit, in the PDU session establishment procedure, when receiving a back-off timer value, and the PDU session establishment acceptance message containing 5GSM cause indicating that establishment of the PDU session is prohibited,
The control unit sets the back-off timer value as a timer for limiting execution of the PDU session establishment procedure,
The transmitting / receiving unit is
Before the timer expires, when a PDU session ID indicating a PDU session and a PDU session change command including 5GSM cause are received,
The user equipment according to claim 2 or 3, wherein the PDU session establishment procedure is executed again based on 5GSM cause even before the timer expires.