WO2019098496A1 - Method for registering, to network system, terminal capable of accessing plurality of access networks - Google Patents

Abstract

One disclosure in the present specification provides a method for registering, to a network system, a terminal capable of accessing a plurality of access networks. The method can comprise the steps of: receiving, from a first AMF through a first access network, a first registration request message including a first identifier; receiving, from a second AMF through a second access network, a second registration request message including a second identifier; and accepting either the first registration request message or the second registration request message and rejecting or ignoring the non-accepted message when a terminal having transmitted the first registration request message is the same as a terminal having transmitted the second registration request message.

Description

A method of registering a terminal connectable to a plurality of access networks to a network system

The present invention relates to next generation mobile communications.

As part of efforts to optimize and improve the performance of 3GPP technologies from the end of 2004 to address the various forums and new technologies related to 4G mobile communication, the 3GPP, which establishes the technical specifications of mobile communication systems, Term Evolution / System Architecture Evolution) technology.

3GPP SA WG2 is a research on network technology aiming at determining network structure and supporting mobility between 3GPP TSG RAN and 3GPP TSG RAN in parallel with LTE work. Recently, important standardization issues of 3GPP Lt; / RTI > This work aims to develop a 3GPP system based on IP as a system supporting various wireless access technologies and aim at an optimized packet based system which minimizes transmission delay with improved data transmission ability.

The Evolved Packet System (EPS) reference model (reference mode 1) defined in the 3GPP SA WG2 includes a non-roaming case and roaming cases of various scenarios, Document TS 23.401 and TS 23.402. The network structure of FIG. 1 is a simplified reconstruction thereof.

1 is a structural diagram of an evolved mobile communication network.

The EPC may include various components. In FIG. 1, an S-GW (Serving Gateway) 52, a PDN GW (Packet Data Network Gateway) 53, an MME (Mobility Management Entity) (SGSN) 51, a Serving GPRS (General Packet Radio Service) Supporting Node, and an ePDG (Enhanced Packet Data Gateway).

The S-GW 52 is an element that functions as a boundary point between the radio access network (RAN) and the core network and functions to maintain a data path between the eNodeB 20 and the PDN GW 53. In addition, when the UE (or User Equipment) moves across the area served by the eNodeB 20, the S-GW 52 acts as a local mobility anchor point. That is, the packets may be routed through the S-GW 52 for mobility within the E-UTRAN (Evolved-Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network defined after 3GPP Release-8). In addition, the S-GW 52 may communicate with another 3GPP network (RAN defined before 3GPP Release-8, e.g., UTRAN or GERAN (Enhanced Data Rates for Global Evolution) Network) as an anchor point for mobility.

The PDN GW (or P-GW) 53 corresponds to the termination point of the data interface toward the packet data network. The PDN GW 53 may support policy enforcement features, packet filtering, charging support, and the like. In addition, mobility management with 3GPP networks and non-3GPP networks (e.g., untrusted networks such as Interworking Wireless Local Area Network (I-WLAN), Code Division Multiple Access (CDMA) networks or trusted networks such as WiMax) It can serve as an anchor point for.

Although the example of the network structure of FIG. 1 shows that the S-GW 52 and the PDN GW 53 are configured as separate gateways, two gateways may be implemented according to a single gateway configuration option have.

The MME 51 is an element for performing signaling and control functions for supporting access to a network connection, network resource allocation, tracking, paging, roaming, and handover of the UE . The MME 51 controls control plane functions related to subscriber and session management. The MME 51 manages a large number of eNodeBs 20 and performs signaling for selection of a conventional gateway for handover to another 2G / 3G network. The MME 51 also performs functions such as security procedures, terminal-to-network session handling, and idle terminal location management.

The SGSN handles all packet data such as the user's mobility management and authentication to other connected 3GPP networks (e.g., GPRS network, UTRAN / GERAN).

ePDG acts as a secure node for an untrusted Non-3GPP network (e.g., I-WLAN, WiFi hotspot, etc.).

As described with reference to FIG. 1, a terminal (or a UE) having IP capability is not limited to a 3GPP access but also a non-3GPP access base and may be provided by a carrier (i.e., an operator) via various elements in the EPC. IP service network (e.g., IMS).

1 also shows various reference points (e.g., S1-U, S1-MME, etc.). In 3GPP system, a conceptual link connecting two functions existing in different functional entities of E-UTRAN and EPC is defined as a reference point. The following Table 1 summarizes the reference points shown in FIG. In addition to the examples in Table 1, various reference points may exist depending on the network structure.

Reference point	Explanation
S1-MME	A reference point for the control plane protocol between the E-UTRAN and the MME (reference point for the control plane protocol between the E-UTRAN and the MME)
S1-U	A reference point between E-UTRAN and Serving GW for the path switching between eNBs during handover and user plane tunneling per bearer;
S3	A reference point between an MME and an SGSN that provides user and bearer information exchange for 3GPP access network mobility in an idle and / or active state. This reference point may be used in PLMN- or PLMN- (e.g., in the case of a PLMN-to-PLMN handover)) (It enables user and bearer information exchange for inter-3GPP access network mobility in Idle and / or active state . This reference point can be used intra-PLMN or inter-PLMN (e.g., in the case of Inter-PLMN HO).
S4	A reference point between the SGW and the SGSN that provides the associated control and mobility support between the GPRS core and the 3GPP anchor function of the SGW. In addition, if a direct tunnel is not established, it provides user plane tunneling. (It provides related user control functions such as GPRS core and the 3GPP anchor function of Serving GW. In addition, if Direct Tunnel is not established, .)
S5	A reference point that provides user plane tunneling and tunnel management between the SGW and the PDN GW. It is used for SGW relocation due to UE mobility and for connection to PDN GW where SGW does not co-exist for required PDN connectivity. It is used for Serving GW and PDN GW. Serving GW relocation due to UE mobility and if Serving GW needs to connect to a non-collocated PDN GW for the required PDN connectivity.
S11	Reference point between MME and SGW
SGi	PDN Reference point between GW and PDN. The PDN may be an operator external public or private PDN or, for example, an operator-in-PDN for the provision of an IMS service. This reference point corresponds to the 3G of the 3GPP access (it is the reference point between the PDN GW and the packet data network, the packet data network may be an operator external public or a private packet data network or an intra-operator packet data network, This reference point corresponds to 3G for 3GPP accesses.

Among the reference points shown in FIG. 1, S2a and S2b correspond to a Non-3GPP interface. S2a is a reference point that provides the user plane with the associated control and mobility support between trusted Non-3GPP access and PDN GW. S2b is a reference point providing the user plane with the associated control and mobility support between the ePDG and the PDN GW.

<Next Generation Mobile Communication Network>

Thanks to the success of LTE (Long Term Evolution) and LTE-Advanced (LTE-A) for 4G mobile communication, interest in the next generation, namely 5G (so called 5G) mobile communication is growing and research is proceeding .

The fifth generation mobile telecommunications defined by the International Telecommunication Union (ITU) refers to providing a data transmission rate of up to 20 Gbps and a minimum transmission speed of at least 100 Mbps anywhere. The official name is 'IMT-2020' and aims to commercialize it worldwide in 2020.

ITU proposes three usage scenarios, for example, enhanced Mobile BroadBand (eMBB) and Massive Machine Type Communication (mMTC) and Ultra Reliable and Low Latency Communications (URLLC).

First, URLLC is about usage scenarios that require high reliability and low latency. For example, services such as autonomous navigation, factory automation, augmented reality require high reliability and low latency (e.g., a delay time of less than 1 ms). Currently, the delay time of 4G (LTE) is statistically 21-43ms (best 10%) and 33-75ms (median). This is insufficient to support a service requiring a delay time of 1 ms or less.

Next, the eMBB usage scenario relates to usage scenarios requiring mobile ultra-wideband.

This ultra-high-speed, high-speed service seems unacceptable by core networks designed for LTE / LTE-A.

Therefore, in the so-called fifth generation mobile communication, a redesign of the core network is urgently required.

Fig. 2 is an exemplary diagram showing the expected structure of the next generation mobile communication from the viewpoint of a node.

As can be seen with reference to FIG. 2, the UE is connected to a data network (DN) through a next generation RAN (Radio Access Network).

The Control Plane Function (CPF) node shown in the figure represents all or part of the functions of the MME (Mobility Management Entity) of the fourth generation mobile communication, the control plane function of the Serving Gateway (S-GW) and the PDN Gateway Of the present invention. The CPF node includes an Access and Mobility Management Function (AMF) and a Session Management Function (SMF).

The User Plane Function (UPF) node is a type of gateway through which user data is transmitted and received. The UPF node may perform all or part of the user plane functions of the S-GW and the P-GW of the fourth generation mobile communication.

The PCF (Policy Control Function) shown in the figure is a node that controls the policy of the provider.

The illustrated Application Function (AF) is a server for providing various services to the UE.

The Unified Data Management (UDM) shown is a type of server that manages subscriber information, such as an HSS (Home Subscriber Server) of a fourth generation mobile communication. The UDM stores and manages the subscriber information in a Unified Data Repository (UDR).

The illustrated Authentication Server Function (AUSF) authenticates and manages the UE.

The illustrated Network Slice Selection Function (NSSF) is a node for network slicing as described below.

On the other hand, there are two ways in which the UE handles a signaling request from the UE in a situation where it roams to a visited network, for example, a V-PLMN. The first method, the local break out (LBO) scheme, handles the signaling request from the UE in the visited network. According to the second scheme, Home Routing (HR) scheme, the visited network forwards the signaling request from the UE to the home network of the UE.

Figure 3 generally shows that E- UTRAN and  FIG. 8 is a diagram illustrating functions of a main node of a general EPC. FIG.

As shown, the eNodeB 20 is responsible for routing to the gateway, scheduling and transmission of the paging signal, scheduling and transmission of the Broadcast Channel (BCH) while uplink and downlink And may perform functions for dynamic allocation of resources to the UE, setting and provision for measurement of the eNodeB 20, radio bearer control, radio admission control, and connection mobility control. In EPC, paging, LTE_IDLE state management, user plane encryption, EPS bearer control, NAS signaling encryption and integrity protection functions can be performed.

Figure 4 UE and eNodeB  The structure of the radio interface protocol in the control plane between For example, , And FIG. 5 is another example of a structure of a radio interface protocol between a terminal and a base station in a user plane.

The air interface protocol is based on the 3GPP radio access network standard. The wireless interface protocol horizontally comprises a physical layer, a data link layer, and a network layer, and vertically includes a user plane for data information transmission and a control plane And a control plane for signal transmission.

The protocol layers are classified into L1 (first layer), L2 (second layer) and L3 (third layer) based on the lower three layers of an Open System Interconnection (OSI) ).

Hereinafter, the layers of the wireless protocol in the control plane shown in FIG. 4 and the wireless protocol in the user plane shown in FIG. 5 will be described.

The physical layer, which is the first layer, provides an information transfer service using a physical channel. The physical layer is connected to an upper Medium Access Control layer through a transport channel, and data is transmitted between the medium access control layer and the physical layer through the transport channel. Data is transmitted between the different physical layers, that is, between the transmitting side and the receiving side physical layer through the physical channel.

A physical channel is composed of several subframes on the time axis and several subcarriers on the frequency axis. Here, one sub-frame is composed of a plurality of symbols and a plurality of sub-carriers on the time axis. One subframe is composed of a plurality of resource blocks, and one resource block is composed of a plurality of symbols and a plurality of subcarriers. The transmission time interval (TTI), which is the unit time at which data is transmitted, is 1 ms corresponding to one subframe.

According to 3GPP LTE, the physical channels existing in the physical layer of the transmitter and the receiver can be classified into a Physical Downlink Shared Channel (PDSCH), a Physical Uplink Shared Channel (PUSCH) and a Physical Downlink Control Channel (PDCCH) A Physical Control Format Indicator Channel (PCFICH), a Physical Hybrid-ARQ Indicator Channel (PHICH), and a Physical Uplink Control Channel (PUCCH).

The PCFICH transmitted in the first OFDM symbol of the subframe carries a control format indicator (CFI) regarding the number of OFDM symbols (i.e., the size of the control region) used for transmission of the control channels in the subframe. The wireless device first receives the CFI on the PCFICH and then monitors the PDCCH.

Unlike PDCCH, PCFICH does not use blind decoding, but is transmitted via fixed PCFICH resources in the subframe.

The PHICH carries an ACK (positive-acknowledgment) / NACK (negative-acknowledgment) signal for a hybrid automatic repeat request (UL HARQ). The ACK / NACK signal for UL (uplink) data on the PUSCH transmitted by the wireless device is transmitted on the PHICH.

A PBCH (Physical Broadcast Channel) is transmitted in four OFDM symbols preceding the second slot of the first subframe of the radio frame. The PBCH carries the system information necessary for the radio equipment to communicate with the base station, and the system information transmitted through the PBCH is called the master information block (MIB). In contrast, the system information transmitted on the PDSCH indicated by the PDCCH is called a system information block (SIB).

The PDCCH includes a resource allocation and transmission format of a downlink-shared channel (DL-SCH), resource allocation information of an uplink shared channel (UL-SCH), paging information on a PCH, system information on a DL- Resource allocation of upper layer control messages such as responses, aggregation of transmission power control commands for individual UEs in any UE group, and activation of voice over internet protocol (VoIP). A plurality of PDCCHs can be transmitted in the control domain, and the UE can monitor a plurality of PDCCHs. The PDCCH is transmitted on an aggregation of one or several consecutive control channel elements (CCEs). The CCE is a logical allocation unit used to provide the PDCCH with the coding rate according to the state of the radio channel. The CCE corresponds to a plurality of resource element groups. The format of the PDCCH and the number of bits of the possible PDCCH are determined according to the relationship between the number of CCEs and the coding rate provided by the CCEs.

The control information transmitted through the PDCCH is referred to as downlink control information (DCI). The DCI includes a resource allocation (also referred to as a DL grant) of the PDSCH, a resource allocation (also referred to as an UL grant) of the PUSCH, a set of transmission power control commands for individual UEs in any UE group And / or Voice over Internet Protocol (VoIP).

There are several layers in the second layer. First, the Medium Access Control (MAC) layer maps various logical channels to various transport channels, and also performs logical channel multiplexing in which a plurality of logical channels are mapped to one transport channel Role. The MAC layer is connected to an RLC layer, which is an upper layer, through a logical channel. A logical channel includes a control channel for transmitting control plane information according to the type of information to be transmitted, And a traffic channel for transmitting information of a user plane (User Plane).

The Radio Link Control (RLC) layer of the second layer divides and concatenates the data received from the upper layer to adjust the data size so that the lower layer is suitable for transmitting data in the radio section . In order to guarantee various QoSs required by each radio bearer (RB), a TM (transparent mode), a UM (un-acknowledged mode), and an AM (acknowledged mode) And a response mode). In particular, the AM RLC performs a retransmission function through an automatic repeat and request (ARQ) function for reliable data transmission.

The Packet Data Convergence Protocol (PDCP) layer of the second layer is an IP (Packet Data Convergence Protocol) layer that is relatively large and contains unnecessary control information in order to efficiently transmit IP packets, such as IPv4 or IPv6, It performs header compression to reduce packet header size. This makes it possible to transmit only necessary information in the header portion of the data, thereby increasing the transmission efficiency of the radio section. In the LTE system, the PDCP layer also performs a security function, which consists of ciphering to prevent third party data interception and integrity protection to prevent third party data manipulation.

A radio resource control (RRC) layer located at the uppermost layer of the third layer is defined only in the control plane, and is used for setting (setting) and resetting (Re) a radio bearer - Setting) and Release of the logical channel, the transport channel and the physical channel. At this time, the RB means a service provided by the second layer for data transmission between the UE and the E-UTRAN.

When there is an RRC connection between the RRC of the UE and the RRC layer of the wireless network, the UE is in the RRC connection state (Connected mode), and if not, the UE is in the RRC idle mode.

Hereinafter, the RRC state (RRC state) and the RRC connection method of the UE will be described. The RRC state refers to whether or not the RRC of the UE is a logical connection with the RRC of the E-UTRAN. If the RRC is connected, it is called the RRC_CONNECTED state, and if it is not connected, it is called the RRC_IDLE state. Since the UE in the RRC_CONNECTED state has the RRC connection, the E-UTRAN can grasp the existence of the UE in the cell unit, and thus can effectively control the UE. On the other hand, the terminal in the RRC_IDLE state can not grasp the existence of the terminal in the E-UTRAN, and the core network manages the TA (Tracking Area) unit, which is a larger area unit than the cell. That is, the UE in the RRC_IDLE state only knows whether the corresponding UE is present in a larger area than the cell, and the UE must transition to the RRC_CONNECTED state in order to receive ordinary mobile communication services such as voice or data. Each TA is identified by a tracking area identity (TAI). A terminal can construct a TAI through a tracking area code (TAC), which is information broadcast in a cell.

When the user first turns on the power of the terminal, the terminal first searches for an appropriate cell, establishes an RRC connection in the corresponding cell, and registers the terminal information in the core network. Thereafter, the terminal remains in the RRC_IDLE state. The terminal staying in the RRC_IDLE state selects (re-selects) the cell as needed and checks the system information and paging information. It is said to camp on the cell. When a terminal that has stayed in the RRC_IDLE state needs to establish an RRC connection, the terminal establishes an RRC connection with the RRC of the E-UTRAN through the RRC connection procedure and transitions to the RRC_CONNECTED state. There are a number of cases where the UE in the RRC_IDLE state needs to establish an RRC connection. For example, if uplink data transmission is required due to a user's call attempt or the like, or if a paging signal is received from the E-UTRAN And transmission of a response message to the user.

A non-access stratum (NAS) layer located at an upper level of the RRC layer performs functions such as session management and mobility management.

The NAS layer shown in FIG. 4 will be described in detail below.

ESM (Evolved Session Management) belonging to the NAS layer performs functions such as default bearer management and dedicated bearer management, and the terminal is responsible for controlling the PS service from the network. The default bearer resource is allocated from the network when it is first connected to a specific Packet Data Network (PDN) when connected to the network. At this time, the network allocates available IP addresses to the UE so that the UE can use the data service, and allocates the QoS of the default bearer. LTE supports two types of bearers: Guaranteed bit rate (GBR) QoS, which guarantees a specific bandwidth for data transmission and reception, and Non-GBR bearer, which has best effort QoS without bandwidth guarantee. In the case of the default bearer, a non-GBR bearer is allocated. In the case of a dedicated bearer, bearers having QoS characteristics of GBR or non-GBR can be allocated.

A bearer assigned to a terminal in the network is called an evolved packet service (EPS) bearer. When allocating an EPS bearer, the network assigns an ID. This is called EPS Bearer ID. One EPS bearer has a maximum bit rate (MBR) and a guaranteed bit rate (GBR) or an aggregated maximum bit rate (AMBR) QoS characteristic.

In FIG. 4, an RRC layer, an RLC layer, a MAC layer, and a PHY layer located under the NAS layer are collectively referred to as an access layer (AS).

6A is a flowchart illustrating a random access procedure in 3GPP LTE.

The random access procedure is used by the UE 10 to obtain UL synchronization with the base station, eNodeB 20, or to allocate UL radio resources.

The UE 10 receives a root index and a physical random access channel (PRACH) setting index (setting index) from the eNodeB 20. Each cell has 64 candidate random access preambles defined by a Zadoff-Chu (ZC) sequence, and the root index is a logical index for the UE to generate 64 candidate random access preambles.

The transmission of the random access preamble is limited to specific time and frequency resources for each cell. The PRACH setting index indicates a specific subframe and a preamble format in which a random access preamble can be transmitted.

The UE 10 transmits the randomly selected random access preamble to the eNodeB 20. UE 10 selects one of 64 candidate random access preambles. Then, the corresponding subframe is selected by the PRACH setting index. UE 10 transmits the selected random access preamble in the selected subframe.

The eNodeB 20 receiving the random access preamble sends a random access response (RAR) to the UE 10. The random access response is detected in two steps. First, the UE 10 detects a PDCCH masked with a random access-RNTI (RA-RNTI). The UE 10 receives a random access response in a MAC (Medium Access Control) PDU (Protocol Data Unit) on the PDSCH indicated by the detected PDCCH.

6B shows a connection procedure in the radio resource control (RRC) layer.

As shown in FIG. 6B, the RRC state is shown depending on whether the RRC is connected or not. The RRC state refers to whether or not an entity of the RRC layer of the UE 10 is a logical connection with an entity of the RRC layer of the eNodeB 20, state, and an unconnected state is called an RRC idle state.

Since the UE 10 in the connected state has an RRC connection, the E-UTRAN can grasp the existence of the UE in cell units, and thus can effectively control the UE 10. On the other hand, the UE 10 in an idle state can not grasp by the eNodeB 20, but is managed by a core network in units of a tracking area, which is an area unit larger than a cell. The tracking area is a set of cells. That is, the idle state UE 10 only knows whether a UE exists in a large area, and in order to receive normal mobile communication services such as voice or data, the UE must transition to a connected state.

When the user first turns on the power of the UE 10, the UE 10 first searches for an appropriate cell and stays in an idle state in the corresponding cell. The UE 10 staying in the idle state establishes an RRC connection with the RRC layer of the eNodeB 20 via the RRC connection procedure when the UE 10 needs to make an RRC connection, connected state.

There are many cases where the UE in the idle state needs to make an RRC connection. For example, if the UE needs a call attempt or uplink data transmission, or receives a paging message from the EUTRAN And sending a response message to the user.

In order for the UE 10 in an idle state to make an RRC connection with the eNodeB 20, the RRC connection procedure should be performed as described above. The RRC connection process is roughly divided into a process in which the UE 10 transmits an RRC connection request message to the eNodeB 20 and a process in which the eNodeB 20 transmits an RRC connection setup message to the UE 10 And transmitting the RRC connection setup complete message to the eNodeB 20 by the UE 10. This process will be described in more detail with reference to FIG. 6B.

1) When the UE 10 in an idle state tries to establish an RRC connection for a reason such as a call attempt, a data transmission attempt, or a response to the paging of the eNodeB 20, the UE 10 first transmits an RRC And transmits a connection request (RRC connection request) message to the eNodeB 20.

2) Upon receiving the RRC connection request message from the UE 10, the eNB 20 accepts the RRC connection request of the UE 10 when the radio resources are sufficient and transmits a RRC connection setup message to the UE 10.

3) When the UE 10 receives the RRC connection setup message, it transmits an RRC connection setup complete message to the eNodeB 20. When the UE 10 successfully transmits an RRC connection setup message, the UE 10 establishes an RRC connection with the eNodeB 20 and transitions to the RRC connection mode.

On the other hand, in an LTE (E-UTRAN) system, when a terminal is connected to an EPC through a non-3GPP access network (e.g., a WLAN access network) unlike the case where a terminal is connected via an EPC via a 3GPP access network, And thus there was no network function to manage the MM context.

However, in the case of the 5G system, when the terminal is connected to the NG (NextGeneration) core network via the Non-3GPP access network, it is assumed to use NAS signaling as well as to connect to the NG core network via the 3GPP access network. Accordingly, when connected to the NG core network through the non-3GPP access network, the terminal and the NG core network perform the NAS attach procedure, and the AMF of the NG core network transmits the Manage / maintain MM context.

When a terminal connects to a NG core network at the same time via a 3GPP access network and a Non-3GPP access network, the fact that one AMF manages two connections, regardless of the type of access network, .

However, when the terminal is connected (or attached or authenticated) to the NG core network through any one of the 3GPP access network and the non-3GPP access network (for convenience, the first access network) , The second access network), there may arise a problem that the same AMF is not allocated / designated.

In order to achieve the above object, one disclosure of the present disclosure discloses a method of registering a terminal capable of connecting to a plurality of access networks in a network system. The method includes receiving a first registration request message including a first identifier from a first Access and Mobility Management Function (AMF) over a first access network; Receiving a second registration request message from a second AMF over a second access network, the second registration request message including a second identifier; Accepting only one of the first registration request message and the second registration request message when the terminal transmitting the first registration request message and the terminal transmitting the second registration request message are identical, .

And re-receiving the second registration request message from the first AMF over the second access network after rejecting or ignoring registration of the terminal via the second access network.

Wherein the step of determining the identity of the terminal transmitting the first registration request message and the terminal transmitting the second registration request message comprises determining whether the first identifier and the second identifier are identical , The first identifier and the second identifier may be Globally Unique Temporary Identifiers (GUTIs).

Wherein the step of determining the identity of the terminal that transmitted the first registration request message and the terminal that transmitted the second registration request message comprises: comparing a Subscription Permanent Identifier (SUPI) generated using the first identifier, And determining whether the generated SUPI is the same, wherein the first identifier and the second identifier may be a Subscription Conceal Identifier (SUCI).

The method of claim 1, further comprising transmitting a message indicating rejection to the terminal when the other registration message is rejected, wherein the message indicating rejection indicates that the terminal has already received the registration request message, It may indicate duplication.

The first access network is a 3GPP access network and the second access network is a Non-3GPP access network or the first access network is a Non-3GPP access network and the second access network may be a 3GPP access network .

When the first registration request message is received before the second registration request message, the accepted message is a first registration request message, and when the second registration request message is received before the first registration request message, The accepted message may be a second registration request message.

In order to achieve the above object, another disclosure of the present disclosure discloses a method for a terminal capable of connecting to a plurality of access networks to perform registration in a network system. The method includes receiving a first registration response message from a first Access and Mobility Management Function (AMF) over a first access network, the first registration response message including a first identifier of the terminal; Receiving a second registration response message from a second AMF over a second access network, the second registration response message comprising a second identifier of the terminal; And transmitting a deregistration request message to either the first AMF or the second AMF when the first identifier and the second identifier are different from each other, And may include any one of the second identifiers.

According to one disclosure of the present specification, unnecessary network resource waste can be prevented by providing a method of efficiently registering a terminal in a network system via a 3GPP access network and a Non-3GPP access network.

1 is a structural diagram of an evolved mobile communication network.

Fig. 2 is an exemplary diagram showing the expected structure of the next generation mobile communication from the viewpoint of a node.

3 is an exemplary diagram illustrating an architecture of a general EPC with an E-UTRAN in general.

4 is a diagram illustrating a structure of a radio interface protocol in a control plane between a UE and an eNodeB.

5 is another example of a structure of a radio interface protocol in a user plane between a terminal and a base station.

6A is a flowchart illustrating a random access procedure in 3GPP LTE.

6B shows a connection procedure in the radio resource control (RRC) layer.

7 shows a network registration procedure according to the first disclosure of the present specification.

8A shows a network registration procedure according to a first example of the second disclosure of the present disclosure.

8B shows a network registration procedure according to a second example of the second disclosure of the present disclosure.

8C shows a network registration procedure according to a third example of the second disclosure of the present disclosure.

9 shows a network registration procedure according to the third disclosure of the present specification.

10 shows a network registration procedure according to the fourth disclosure of the present specification.

11 is a block diagram illustrating a wireless communication system in which the embodiments presented herein are implemented.

Although the present invention is described based on a Universal Mobile Telecommunication System (UMTS) and an Evolved Packet Core (EPC), the present invention is not limited to such a communication system but may be applied to all communication systems and methods to which the technical idea of the present invention can be applied Can be applied.

It is noted that the technical terms used herein are used only to describe specific embodiments and are not intended to limit the invention. It is also to be understood that the technical terms used herein are to be interpreted in a sense generally understood by a person skilled in the art to which the present invention belongs, Should not be construed to mean, or be interpreted in an excessively reduced sense. Further, when a technical term used herein is an erroneous technical term that does not accurately express the spirit of the present invention, it should be understood that technical terms that can be understood by a person skilled in the art are replaced. In addition, the general terms used in the present invention should be interpreted according to a predefined or prior context, and should not be construed as being excessively reduced.

Also, the singular forms "as used herein include plural referents unless the context clearly dictates otherwise. It is to be understood that the term "comprising" or "comprising" in this application should not be construed as necessarily including the various elements or steps described in the specification, and some of the elements or some of the steps may not be included , &Lt; / RTI &gt; or additional components or steps.

Furthermore, terms including ordinals such as first, second, etc. used in this specification can be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

When an element is referred to as being connected or connected to another element, it may be directly connected or connected to the other element, but other elements may be present in between. On the other hand, when it is mentioned that an element is directly connected or directly connected to another element, it should be understood that no other element exists in between.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like or similar elements throughout the several views, and redundant description thereof will be omitted. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. It is to be noted that the accompanying drawings are only for the understanding of the present invention and should not be construed as limiting the scope of the present invention. The spirit of the present invention should be construed as extending to all modifications, equivalents, and alternatives in addition to the appended drawings.

Although a UE (User Equipment) is illustrated as an example in the accompanying drawings, the UE may be referred to as a terminal, a mobile equipment (ME), or the like. Also, the UE may be a portable device such as a notebook computer, a mobile phone, a PDA, a smart phone, a multimedia device, or the like, or a portable device such as a PC or a vehicle-mounted device.

Definition of Terms

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the present invention with reference to the accompanying drawings, the terms used in this specification will be briefly defined to facilitate understanding of the present invention.

UMTS: Abbreviation of Universal Mobile Telecommunication System, which means 3rd generation mobile communication network.

UE / MS: User Equipment / Mobile Station.

EPS: Abbreviation of Evolved Packet System, which means a core network supporting LTE (Long Term Evolution) network. UMTS is an evolved form of network

PDN (Public Data Network): An independent network where servers providing services are located

PDN connection: A connection from a terminal to a PDN, that is, a connection between a terminal represented by an IP address and a PDN represented by an APN,

PDN-GW (Packet Data Network Gateway): A network node of an EPS network performing UE IP address allocation, packet screening & filtering,

Serving GW (Serving Gateway): A network node in an EPS network that performs mobility anchor, packet routing, idle mode packet buffering, and triggering MME to page UE functions.

PCRF (Policy and Charging Rule Function): A node of the EPS network that performs policy decision to dynamically apply differentiated QoS and charging policies for each service flow.

APN (Access Point Name): Provided to the UE as the name of an access point managed in the network. That is, a string that points to or identifies the PDN. In order to access the requested service or network (PDN), it goes through the P-GW. The name (string) defined in advance in the network so that the P-GW can be found (eg) internet.mnc012.mcc345.gprs

TEID (Tunnel Endpoint Identifier): The end point ID of the tunnel established between the nodes in the network, and is set for each UE in units of bearers.

NodeB: It is installed outdoors as a base station of the UMTS network, and the cell coverage scale corresponds to a macro cell.

eNodeB: It is installed outdoors as base station of EPS (Evolved Packet System), and cell coverage scale corresponds to macro cell.

(e) NodeB: A term referring to a NodeB and an eNodeB.

MME: Abbreviation of Mobility Management Entity, which controls each entity within the EPS to provide session and mobility for the UE.

Session: A session is a path for data transmission, which can be a PDN, a bearer, or an IP flow unit. The difference of each unit can be classified into a whole network unit (APN or PDN unit), a QoS unit (Bearer unit), and a destination IP address unit, as defined in 3GPP.

PDN connection: A connection from a terminal to a PDN, that is, an association (connection) between a terminal represented by an IP address and a PDN represented by an APN. This means an inter-entity connection (terminal-PDN GW) in the core network so that a session can be formed.

UE Context: Context information composed of UE context information, ie, UE id, mobility (current location, etc.), session attributes (QoS, priority, etc.) used for managing UEs in the network

Open Mobile Alliance Device Management (OMA DM) is a protocol designed to manage mobile devices such as mobile phones, PDAs, and portable computers. It is used for device settings (settings), firmware upgrades, and error reports Function

OAM (Operation Administration and Maintenance): OAM is a group of network management functions that provide network fault indication, performance information, and data and diagnostic functions.

NAS Configuration Management Object (MO): A management object (MO) used to set (set) the parameters associated with the NAS function (Functionality) to the UE.

NAS (Non-Access-Stratum): Upper stratum of control plane between UE and MME. Support for mobility management, session management and IP address maintenance between UE and network

MM (Mobility Management) operation / procedure: An operation or procedure for controlling / managing / controlling mobility of UE. The MM operation / procedure can be interpreted to include one or more of the MM operation / procedure in the CS network, the GMM operation / procedure in the GPRS network, and the EMM operation / procedure in the EPS network. The UE and network nodes (MME, SGSN, MSC) send and receive MM messages to perform MM operations / procedures.

SM (Session Management) Operation / Procedure: An operation or procedure for controlling / managing / processing / handling the UE's user plane and / or bearer context / PDP context. The SM operation / procedure may be interpreted to include one or more of the SM operation / procedure in the GPRS network, the ESM operation / procedure in the EPS network. The UE and network nodes (MME, SGSN) send and receive SM messages to perform SM operations / procedures.

Low priority terminal: A terminal that is set to the lowest order of NAS signals. For further details, refer to the standard documents 3GPP TS 24.301 and TS 24.008.

Normal priority terminal: A general terminal that is not set to a low priority

Dual priority terminal: A terminal set to Dual priority, which is set to the NAS signal low order and can be set to override the set NAS signal low order (i.e., UE which provides dual priority support is set for NAS signaling low priority and also set to override the NAS signaling low priority indicator). For further details, refer to the standard documents 3GPP TS 24.301 and TS 24.008.

PLMN: Acronym for Public Land Mobile Network, which means the network identification number of the operator. In the UE roaming situation, the PLMN is divided into Home PLMN (HPLMN) and Visited PLMN (VPLMN).

&Lt; Disclosure of the present invention &

When a terminal connects to a NG core network at the same time via a 3GPP access network and a Non-3GPP access network, the fact that one AMF manages two connections, regardless of the type of access network, . However, when the terminal is connected (or attached or authenticated) to the NG core network through any one of the 3GPP access network and the non-3GPP access network (for convenience, the first access network) , The second access network), the same AMF may not be allocated / designated. An example of such a case is shown below.

1) When the terminal is connected (or attached or authenticated) to the NG core network via the first access network, but the AMF to be connected is not yet determined, the terminal transmits the NG core network It is possible that different AMFs will be assigned / assigned to the two connections.

2) The terminal is connected (or attached or authenticated) to the NG core network through the first access network. However, a DB (e.g., HSS, UDM (User Data Management), UDR (Or attached or authenticated) to the NG core network via the second access network when the information about the AMF is not updated by the user data repository (User Data Repository), State DB, etc.) May be assigned / assigned.

In order to solve such a problem, the present invention proposes a method for allowing the same AMF to be allocated / assigned when a terminal is simultaneously connected to a NG core network through a 3GPP access network and a non-3GPP access network.

The method proposed by the present invention is interpreted as a method in which the same AMF manages the connection of a terminal regardless of which access network the NAS message exchanged with the terminal connected to the NG core network through the 3GPP access network and the non-3GPP access network is transmitted to It is possible.

The registration in this specification may include both initial registration (attach) and re-registration (e.g., periodic registration update, mobility registration update, registration update based on capability change, etc.).

The first access network in this specification may refer to either a 3GPP access network and a Non-3GPP access network (e.g., WLAN), and the second access network may be a 3GPP access network and a non- It can mean any one other than the network.

Also, in this specification, the PLMN (Public Land Mobile Network) for the first access network and the PLMN for the second access network are the same as the first access network is a 3GPP access network and the second access network is a non- , It may mean that the PLMN for the first access network (or RAN, gNB) and the PLMN for N3IWF are the same.

Ⅰ. First Invention

7 shows a network registration procedure according to the first disclosure of the present specification.

Referring to Fig. 7, the first disclosure of the present specification discloses that the terminal can perform the registration procedure to the NG core network via the first access network simultaneously (or before completing the registration procedure via the first access network) When the AMF selected for performing the registration procedure through the first access network and the AMF selected for performing the registration procedure through the second access network are the same when performing the registration procedure with the NG core network via the access network , And proposes the operation of the AMF and the terminal.

When the UE performs the registration procedure through the first access network, the UE transmits a Subscription Conceal Identifier (SUCI) or a registration request message including a Globally Unique Temporary Identifier (GUTI) previously received from the network system to the AMF . That is, if the UE has a GUTI previously received from the network system, it can transmit the registration request message including the GUTI to the AMF. If the UE does not have the GUTI, the UE can transmit the registration request message including the SUCI to the AMF. The GUTI may be a GUTI used in a 5G system.

When the terminal performs the registration procedure through the second access network, the terminal can operate in the same way as when performing the registration procedure through the first access network. That is, when the UE performs the registration procedure through the second access network, the UE can transmit the SUCI or the Registration Request message including the GUTI previously received from the network system to the AMF. That is, if the UE has a GUTI previously received from the network system, it can transmit the registration request message including the GUTI to the AMF. If the UE does not have the GUTI, the UE can transmit the registration request message including the SUCI to the AMF.

For example, in the case where the terminal performs the registration procedure with the NG core network through the first access network and the second access network using the registration request message including the GUTI, As the GUTIs provided in the registration procedure through the second access network are the same, the AMF can recognize that the registration procedure via the first access network and the registration procedure via the second access network are being performed by the same terminal have.

In addition, when the UE performs the registration procedure with the NG core network through the first access network and the second access network using the registration request message including the SUCI, the UE transmits the first SUCI And the second SUCI transmitted through the second access network may be different from each other. Accordingly, the AMF can select an AUSF (Authentication Server Function) based on the first SUCI and the second SUCI, respectively, and the AMF can perform the terminal authentication procedure with the selected AUSF.

Among terminal authentication procedures, AUSF can obtain authentication data from UDM (Unified Data Management). When the terminal authentication procedure is completed, the AUSF can transmit security related information to the AMF. The security-related information may include a SUPI (Subscription Permanent Identifier) corresponding to the SUCI.

The SUPI corresponding to the first SUCI and the SUPI corresponding to the second SUCI may be the same. Since the SUPI corresponding to the first SUCI and the SUPI corresponding to the second SUCI are equal to each other, the AMF can be configured such that the terminal performing the registration procedure through the first access network and the terminal performing the registration procedure through the second access network, Can be recognized.

A supervisor timer is activated when the terminal performs the registration procedure with the NG core network through the first access network and when the terminal performs the registration procedure with the NG core network via the second access network, a supervisor timer may be activated.

1. Operation of AMF

When the AMF receives a registration request to the NG core network via the second access network at the same time as receiving the registration request from the terminal to the NG core network via the first access network or when the AMF receives the registration request from the terminal via the first access network When receiving a registration request to the NG core network and receiving a registration request to the NG core network via the second access network in a state in which the registration procedure through the first access network is not completed, Only the registration procedure via the network can be performed, and the registration procedure via the second access network can be postponed.

The AMF may first send a first response to the registration request to the NG core network via the first access network to the terminal. The first response may include information about the accept or reject of the registration request. The AMF may then send a second response to the registration request to the NG core network via the second access network to the terminal. The second response may include information about the acceptance or rejection of the registration request.

The AMF may allocate / provide the GUTI allocated / provided to the UE when the first response is transmitted to the UE when the second response is transmitted. This means that there is no need to assign a new GUTI to the terminal when the AMF performs the registration procedure over the second access network and the security context generated in the registration procedure via the first access network is the second access It can also mean that it can be used in the registration process via the network.

2. Operation of terminal

When the terminal receives a first response from the AMF for a registration request over the first access network, it can complete the registration procedure via the first access network. At this time, the terminal may stop / abort the first timer for the registration procedure through the first access network.

Thereafter, if the terminal receives a second response to the registration request from the AMF over the second access network, it may complete / terminate the registration procedure via the second access network. The second response may include information about the accept or reject of the registration request.

Ⅱ. The second initiative

The second disclosure of the present disclosure is based on the assumption that the terminal performs the registration procedure to the NG core network via the first access network (or before completing the registration procedure via the first access network) When performing the registration procedure with the network, if the first AMF selected for performing the registration procedure through the first access network and the second AMF selected for performing the registration procedure through the second access network are different from each other, The terminal, the first AMF, and the second AMF.

When the terminal performs the registration procedure through the first access network, the terminal can transmit the registration request message including the SUCI or the GUTI previously received from the network system to the AMF. That is, if the UE has a GUTI previously received from the network system, it can transmit the registration request message including the GUTI to the AMF. If the UE does not have the GUTI, the UE can transmit the registration request message including the SUCI to the AMF. The GUTI may be a GUTI used in a 5G system.

When the terminal performs the registration procedure through the second access network, the terminal can operate in the same way as when performing the registration procedure through the first access network. That is, when the UE performs the registration procedure through the second access network, the UE can transmit the SUCI or the Registration Request message including the GUTI previously received from the network system to the AMF. That is, if the UE has a GUTI previously received from the network system, it can transmit the registration request message including the GUTI to the AMF. If the UE does not have the GUTI, the UE can transmit the registration request message including the SUCI to the AMF.

For example, in the case where the terminal performs the registration procedure with the NG core network through the first access network and the second access network using the registration request message including the GUTI, As the GUTIs provided in the registration procedure through the second access network are the same, the AMF can recognize that the registration procedure via the first access network and the registration procedure via the second access network are being performed by the same terminal have.

In addition, when the UE performs the registration procedure with the NG core network through the first access network and the second access network using the registration request message including the SUCI, the UE transmits the first SUCI And the second SUCI transmitted through the second access network may be different from each other. Accordingly, the AMF can select an AUSF (Authentication Server Function) based on the first SUCI and the second SUCI, respectively, and the AMF can perform the terminal authentication procedure with the selected AUSF.

Among terminal authentication procedures, AUSF can obtain authentication data from UDM (Unified Data Management). When the terminal authentication procedure is completed, the AUSF can transmit security related information to the AMF. The security-related information may include a SUPI (Subscription Permanent Identifier) corresponding to the SUCI.

The SUPI corresponding to the first SUCI and the SUPI corresponding to the second SUCI may be the same. Since the SUPI corresponding to the first SUCI and the SUPI corresponding to the second SUCI are identical to each other, the AMF can not guarantee that the terminal performing the registration procedure through the first access network and the terminal performing the registration procedure through the second access network are the same It can recognize that it is a terminal.

A first timer is activated when the terminal performs the registration procedure with the NG core network via the first access network and a second timer is activated when the terminal performs the registration procedure with the NG core network via the second access network have.

1. First example of the second disclosure

8A shows a network registration procedure according to a first example of the second disclosure of the present disclosure.

Referring to FIG. 8A, if the UDM receives a registration request through the first access network from the first AMF and then receives a registration request through the second access network from the second AMF, The second AMF can acquire the SUPI of the terminal upon completion of the terminal authentication procedure. At this time, the SUPI acquired by the first AMF may be the same as the SUPI acquired by the second AMF.

The first AMF may select the UDM based on the acquired SUPI and provide information about the type of the first access network and the acquired SUPI to the UDM. The second AMF may also select the UDM based on the acquired SUPI and provide information about the type of the second access network and the acquired SUPI to the UDM.

Since the UDM receives the same SUPI from the first AMF and the second AMF but the UDM receives different types of information about the types of access networks received from the first and second AMFs, It can be recognized that it is requesting registration through two access networks.

The UDM may first respond to the first AMF by processing the registration request through the first access network it receives. In addition, the UDM may ignore the registration request over the later received second access network, or may send a message indicating rejection of the registration request over the second access network. The message may include a reason (or cause) field of rejection, and the reason (or cause) field of the rejection may indicate that multiple registration requests occurred concurrently over different access networks.

The first AMF may send a first response to the registration request over the first access network to the terminal based on the response received from the UDM. If the UDM ignores the registration request over the second access network, the second AMF may stop / stop the registration procedure via the second access network. Alternatively, if the UDM rejects the registration request over the second access network, the second AMF may send a second response to the terminal including the reason for the rejection.

When the terminal receives the first response, the terminal may complete / terminate the registration procedure via the first access network. At this time, the first timer corresponding to the registration request through the first access network may be stopped / stopped. In addition, if the UE fails to receive a response from the second AMF because the UDM ignores the registration request through the second access network, or if the UE receives a second response indicating rejection of the registration request, After the second timer corresponding to the registration request through the second access network has expired or has been stopped / stopped, it may attempt to register again with the NG core network via the second access network. At this time, according to the embodiment, the terminal performs the registration procedure using the same GUTI used in the registration procedure through the first access network so that the registration procedure through the second access network can be performed using the first AMF .

2. Second example of the second disclosure

8B shows a network registration procedure according to a second example of the second disclosure of the present disclosure.

Referring to FIG. 8B, when the UDM receives a registration request through the first access network from the first AMF and then receives a registration request through the second access network from the second AMF, The AMF and the second AMF can acquire the SUPI of the terminal, respectively. At this time, the SUPI acquired by the first AMF and the SUPI acquired by the second AMF may be the same.

The first AMF may select the UDM based on the acquired SUPI and provide information about the type of the first access network and the acquired SUPI to the UDM. The second AMF may also select the UDM based on the acquired SUPI and provide information about the type of the second access network and the acquired SUPI to the UDM.

Since the UDM receives the same SUPI from the first AMF and the second AMF but the UDM receives different types of information about the types of access networks received from the first and second AMFs, It can be recognized that it is requesting registration through two access networks.

The UDM may first respond to the first AMF by processing the registration request through the first access network it receives. The UDM may also provide the second AMF with the response sent to the first AMF. Accordingly, the second AMF can recognize that the first AMF is processing the registration request of the terminal.

The first AMF may send a first response to the registration request over the first access network to the terminal based on the response received from the UDM. The first response may include information about the acceptance or rejection of the registration request. Since the second AMF recognizes that the first AMF is processing the registration request of the terminal, the second AMF may forward the registration request through the second access network of the terminal to the first AMF. At this time, the second AMF may include information on the reason for the delivery. The first AMF may send a second response to the registration request over the second access network that is received from the second AMF on behalf of the second AMF.

If the terminal receives the first response from the first AMF, the terminal may terminate the registration procedure over the first access network and stop / stop the first timer corresponding to the registration request over the first access network . Thereafter, when the terminal receives the second response from the first AMF, the terminal terminates the registration procedure via the second access network and stops / stops the second timer corresponding to the registration request through the second access network .

In this specification, the AMF handles registration requests over the access network, which may include an AMF assigning a GUTI to the terminal. The GUTI can be equally applied to both registration via the 3GPP access network and registration via the Non-3GPP access network.

3. Third example of the second disclosure

8C shows a network registration procedure according to a third example of the second disclosure of the present disclosure.

8C, when the UDM receives a registration request through the first access network from the first AMF and then receives a registration request through the second access network from the second AMF, when the authentication process of the terminal is completed, The AMF and the second AMF can acquire the SUPI of the terminal, respectively. At this time, the SUPI acquired by the first AMF and the SUPI acquired by the second AMF may be the same.

The first AMF may select the UDM based on the acquired SUPI and provide information about the type of the first access network and the acquired SUPI to the UDM. The second AMF may also select the UDM based on the acquired SUPI and provide information about the type of the second access network and the acquired SUPI to the UDM.

Since the UDM receives the same SUPI from the first AMF and the second AMF but the UDM receives different types of information about the types of access networks received from the first and second AMFs, It can be recognized that it is requesting registration through two access networks.

The UDM may first respond to the first AMF by processing the registration request through the first access network it receives. The UDM may also provide the second AMF with the response sent to the first AMF. Accordingly, the second AMF can recognize that the first AMF is processing the registration request of the terminal.

The first AMF may send a first response to the registration request over the first access network to the terminal based on the response received from the UDM. The first response may include information about the acceptance or rejection of the registration request. Since the second AMF recognizes that the first AMF is processing the registration request of the terminal, the second AMF may request that the first AMF provide a GUTI that it assigns to the terminal. The GUTI allocated to the UE by the first AMF may be a response to the request for registration through the first access, and may be provided by the first AMF to the UE. The second AMF may transmit a second response to the registration request through the second access network to the terminal including the GUTI provided from the first AMF.

If the terminal receives the first response from the first AMF, the terminal may terminate the registration procedure over the first access network and stop / stop the first timer corresponding to the registration request over the first access network . Thereafter, when the terminal receives the second response from the second AMF, the terminal terminates the registration procedure via the second access network and suspends / stops the second timer corresponding to the registration request through the second access network . At this time, the terminal can receive the same GUTI from the first AMF and the second AMF in response to the registration request.

In this specification, the AMF handles registration requests over the access network, which may include an AMF assigning a GUTI to the terminal. The GUTI can be equally applied to both registration via the 3GPP access network and registration via the Non-3GPP access network.

Ⅲ. The third disclosure

9 shows a network registration procedure according to the third disclosure of the present specification.

Referring to FIG. 9, the third disclosure of the present disclosure is directed to a method and apparatus for performing a registration procedure to a NG core network over a first access network (or before completing a registration procedure via a first access network) A first AMF selected to perform a registration procedure via the first access network and a second AMF selected to perform a registration procedure via the second access network when performing a registration procedure with the NG core network via an access network, When the AMFs are different from each other, the operation of the terminal, the first AMF, and the second AMF is proposed.

A first timer is activated when the terminal performs the registration procedure with the NG core network via the first access network and a second timer is activated when the terminal performs the registration procedure with the NG core network via the second access network have.

The first AMF may send a first response to the terminal according to a registration request over the first access network. The first response may comprise a first GUTI. The second AMF may send a second response to the terminal according to a registration request over the second access network. The second response may include a second GUTI.

The first access network and the second access network may be different kinds of networks. For example, when the first access network is either a 3GPP access network and a non-3GPP access network (e.g., a 3GPP access network), the second access network is a 3GPP access network and a non- (E.g., a Non-3GPP access network). Thus, the first GUTI and the second GUTI may be identifiers that are used in the access network with each other. For example, the first GUTI may be an identifier for a 3GPP access network and the second GUTI may be an identifier for a non-3GPP access network. Therefore, the terminal can acquire two different GUTIs from the first AMF and the second AMF.

In order for the connection to the NG core network via the 3GPP access network and the connection to the NG core network via the Non-3GPP access network to be performed using one GUTI from one AMF, the PLMN to which the first access network belongs and the second If the PLMN to which the access network belongs is the same, the UE maintains the first GUTI included in the first response according to the registration request through the first access network performed first, The second GUTI included in the second response can be removed. The terminal may request the second AMF to terminate the registration through the second access to remove the second GUTI included in the second response. The second AMF may transmit a response of acceptance or rejection in response to the registration cancellation request of the terminal.

After the above revocation procedure is completed, the terminal can again perform the registration request through the second access network. At this time, the terminal can perform the registration request again using the first GUTI corresponding to the first access network that is performed first. The re-registration request using the first GUTI is transmitted to the first AMF, and the re-registration procedure can be performed by the first AMF.

The registration termination and re-registration procedure described above is performed in such a manner that the registration procedure through two access networks is performed simultaneously (in parallel), and even if one AMF performs the registration procedure through two access networks, The present invention can be applied to a case where different GUTIs are allocated to terminals in accordance with a registration procedure. That is, when the terminal requests registration to the NG core network through two access networks belonging to the same PLMN and, as a result, different GUTIs are allocated to each access network, the above-described registration cancellation and re-registration procedure can be applied.

If the GUTIs acquired by the terminal according to the registration request through the first access network and the GUTIs acquired by the terminal according to the registration request through the second access network are different, the terminal can operate according to one of the following.

1) The terminal maintains registration with the NG core network via the 3GPP access network, releases the registration to the NG core network via the Non-3GPP access network, and then the same as the GUTI acquired according to the registration through the 3GPP access network Registration with the NG core network via the Non-3GPP access network can be performed again using the GUTI.

2) The terminal maintains registration with the NG core network via the Non-3GPP access network, releases registration with the NG core network via the 3GPP access network, and then transmits the GUTI It is possible to perform registration again with the NG core network through the 3GPP access network by using the same GUTI as that of the NG core network.

3) The terminal maintains registration with respect to the access network that has received the registration approval message first, releases the registration to the access network that received the registration approval message later, and then acquires the registration approval message according to the registration The same GUTI as the GUTI may be used to re-register the access network that received the registration grant message later.

4) The terminal maintains registration for the access network that received the registration approval message later, releases registration for the access network that received the registration approval message first, and then acquires the registration approval message according to the later received registration It is possible to perform registration again with respect to the access network that has received the registration approval message first by using the same GUTI as that of the GUTI.

5) The terminal may transmit the priority (or preference) for the access network to the AMF by including it in the registration request message. Alternatively, a NG core network (e.g., AMF) may send a registration admission message to the terminal including the priority (or preference) for the access network. The terminal can cancel the registration for the access network determined based on the priority (or preference) provided by the terminal or the priority (or preference) received from the NG core network. For example, registration for a high priority access network may be maintained, and registration for a low priority access network may be released. Or a registration with a low priority access network may be maintained, and a registration with a high priority access network may be released.

At this time, if the registration with respect to the access network having a higher priority is maintained, the terminal requests to register again with the access network having a lower priority using the GUTI that is the same as the GUTI acquired according to the registration through the higher priority access network . In addition, when the registration with respect to the access network having a low priority is maintained, the terminal requests the registration with respect to the access network having a high priority by using the same GUTI as the GUTI acquired according to the registration with the access network having the low priority .

6) The terminal can perform the deregistration based on the priority in data transmission. For example, registration for an access network having a high priority in data transmission is maintained, and registration for an access network having a low priority in data transmission can be released. On the contrary, the registration for the access network having a low priority is maintained at the time of data transmission, and the registration for the access network having a high priority at the time of data transmission can be released.

In this case, when registration for an access network having a high priority is maintained during data transmission, the UE uses a GUTI identical to the GUTI acquired according to registration through an access network having a high priority in data transmission, It may request the registration again for the lower access network. Also, when registration for an access network having a low priority is maintained during data transmission, the UE uses a GUTI identical to the GUTI acquired according to registration for an access network having a low priority in data transmission, It may request to register again for a higher access network.

According to the embodiment, the terminal may be set to always operate according to any one of the above 1) to 6), the above 1) to 6) may be selected by the setting of the terminal / network / Lt; / RTI &gt;

In addition, for the access network in which the terminal is to be deregistered, it is possible to delay the generation of the PDU session even though the registration is successful.

IV. Fourth Disclosure

10 shows a network registration procedure according to the fourth disclosure of the present specification.

Referring to FIG. 10, the fourth disclosure of the present disclosure is directed to a method for providing a second NGC core network to a second NGC core network while performing a registration procedure to a NG core network via a first access network (or before completing a registration procedure via a first access network) A first AMF selected to perform a registration procedure via the first access network and a second AMF selected to perform a registration procedure via the second access network when performing a registration procedure with the NG core network via an access network, When the AMFs are different from each other, the operation of the terminal, the first AMF, and the second AMF is proposed.

A first timer is activated when the terminal performs the registration procedure with the NG core network via the first access network and a second timer is activated when the terminal performs the registration procedure with the NG core network via the second access network have.

The first AMF may send a first response to the terminal according to a registration request over the first access network. The first response may comprise a first GUTI. The second AMF may send a second response to the terminal according to a registration request over the second access network. The second response may include a second GUTI.

For example, when the first access network is either a 3GPP access network or a non-3GPP access network (e.g., a 3GPP access network), the first access network and the second access network may be different types of networks, The access network may be any one (e.g., a non-3GPP access network) other than the first access network of the 3GPP access network and the Non-3GPP access network. Thus, the first GUTI and the second GUTI may be identifiers that are used in the access network with each other. For example, the first GUTI may be an identifier for a 3GPP access network and the second GUTI may be an identifier for a non-3GPP access network. Therefore, the terminal can acquire two different GUTIs from the first AMF and the second AMF.

Also, the first AMF may activate the first timer (nw_supervision timer_1) after transmitting the first response, and the second AMF may activate the second timer (nw_supervision timer_2) after transmitting the second response can do.

The UE can transmit a registration completion message including an acknowledgment (ACK) for the first GUTI to the first AMF. When the first AMF receives the registration completion message from the terminal, the first AMF stops the first timer, completes the registration procedure, and can enter the 5GMM_REGISTERED state.

On the other hand, according to the embodiment, when the UE acquires the second GUTI different from the first GUTI, the UE may not transmit the registration completion message including the ACK for the second GUTI to the second AMF. The second AMF waits for the registration completion message until the second timer expires, and when the second timer expires, the second AMF enters the 5GMM_REGISTERED state and terminates the registration procedure.

After the completion of the registration procedure according to the expiration of the second timer, the terminal may request to register again with the NG core network through the second access network. At this time, the terminal may request to register with the NG core network through the second access network again using the first GUTI acquired according to the registration through the first access network. The re-registration request using the first GUTI is transmitted to the first AMF, and the re-registration procedure can be performed by the first AMF.

The registration termination and re-registration procedure described above is performed in such a manner that the registration procedure through two access networks is performed simultaneously (in parallel), and even if one AMF performs the registration procedure through two access networks, The present invention can be applied to a case where different GUTIs are allocated to terminals in accordance with a registration procedure. That is, when the terminal requests registration to the NG core network through two access networks belonging to the same PLMN and, as a result, different GUTIs are allocated to each access network, the above-described registration cancellation and re-registration procedure can be applied.

Ⅴ. Fifth initiation

The fifth disclosure of the present specification can be configured according to a combination of the first to fourth disclosures.

What has been described so far can be implemented in hardware.

11 is a block diagram illustrating a wireless communication system in which the embodiments presented herein are implemented.

The base station 200 includes a processor 201, a memory 202 and an RF unit (radio frequency unit) 203. The memory 202 is connected to the processor 201 and stores various information for driving the processor 201. [ The RF unit 203 is connected to the processor 201 to transmit and / or receive a radio signal. The processor 201 implements the proposed functions, procedures and / or methods. In the above-described embodiment, the operation of the base station can be implemented by the processor 51. [

The wireless device 100 includes a processor 101, a memory 102 and an RF unit 103. [ The memory 102 is connected to the processor 101 and stores various information for driving the processor 101. [ The RF unit 103 is connected to the processor 101 to transmit and / or receive a radio signal. The processor 101 implements the proposed functions, procedures and / or methods. The operation of the wireless device in the above-described embodiment may be implemented by the processor 101. [

The processor may comprise an application-specific integrated circuit (ASIC), other chipset, logic circuitry and / or a data processing device. The memory may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and / or other storage devices. The RF unit may include a baseband circuit for processing the radio signal. When the embodiment is implemented in software, the above-described techniques may be implemented with modules (processes, functions, and so on) that perform the functions described above. The module is stored in memory and can be executed by the processor. The memory may be internal or external to the processor and may be coupled to the processor by any of a variety of well known means.

In the above-described exemplary system, the methods are described on the basis of a flowchart as a series of steps or blocks, but the present invention is not limited to the order of the steps, and some steps may occur in different orders . It will also be understood by those skilled in the art that the steps shown in the flowchart are not exclusive and that other steps may be included or that one or more steps in the flowchart may be deleted without affecting the scope of the invention.

Claims (15)

1. A method for registering a terminal connectable to a plurality of access networks in a network system,

   Receiving a first registration request message including a first identifier from a first Access and Mobility Management Function (AMF) over a first access network;

   Receiving a second registration request message from a second AMF over a second access network, the second registration request message including a second identifier; And

   Accepting only one of the first registration request message and the second registration request message when the terminal transmitting the first registration request message and the terminal transmitting the second registration request message are identical, &Lt; / RTI &gt;
2. The method according to claim 1,

   Further comprising re-receiving the second registration request message from the first AMF over the second access network after rejecting or ignoring registration of the terminal on the second access network.
3. The method as claimed in claim 1, wherein the step of determining whether the terminal transmitting the first registration request message and the terminal transmitting the second registration request message are identical,

   Determining whether the first identifier and the second identifier are the same,

   Wherein the first identifier and the second identifier are Globally Unique Temporary Identifiers (GUTIs).
4. The method as claimed in claim 1, wherein the step of determining whether the terminal transmitting the first registration request message and the terminal transmitting the second registration request message are identical,

   Determining whether a SUPI (Subscription Permanent Identifier) generated using the first identifier is identical to a SUPI generated using the second identifier,

   Wherein the first identifier and the second identifier are SUCI (Subscription Conceal Identifier).
5. The method according to claim 1,

   Further comprising the step of transmitting a message indicating rejection to the terminal if the other registration message is rejected,

   Wherein the message indicating the rejection indicates that the terminal has already received the registration request message or indicates that the registration request is duplicated.
6. The method according to claim 1,

   The first access network is a 3GPP access network and the second access network is a Non-3GPP access network, or

   Wherein the first access network is a Non-3GPP access network and the second access network is a 3GPP access network.
7. The method according to claim 1,

   If the first registration request message is received prior to the second registration request message, the accepted message is a first registration request message,

   And if the second registration request message is received prior to the first registration request message, the accepted message is a second registration request message.
8. A method for a terminal capable of accessing a plurality of access networks to perform registration in a network system,

   The method comprising: receiving a first registration response message from a first Access and Mobility Management Function (AMF) over a first access network, the first registration response message including a first identifier of the terminal;

   Receiving a second registration response message from a second AMF over a second access network, the second registration response message comprising a second identifier of the terminal; And

   And transmitting a deregistration request message to either the first AMF or the second AMF when the first identifier and the second identifier are different,

   Wherein the deregistration request message comprises one of the first identifier and the second identifier.
9. 9. The method of claim 8, wherein the first AMF and the second AMF are different or equal to each other.
10. 9. The method of claim 8,

    Further comprising the step of retransmitting the registration request message to the first AMF through the second access network whose registration is canceled when the registration cancel request message is transmitted to the second AMF,

    Wherein the registration request message includes the first identifier obtained from the first AMF.
11. 9. The method of claim 8,

    Wherein a Public Land Mobile Network (PLMN) of the first access network and a PLMN of the second access network are the same.
12. 9. The method of claim 8,

    Wherein the deregistration request message is transmitted to remove either the first identifier or the second identifier.
13. 9. The method of claim 8,

    The first access network is a 3GPP access network and the second access network is a Non-3GPP access network, or

    Wherein the first access network is a Non-3GPP access network and the second access network is a 3GPP access network.
14. 9. The method of claim 8,

    Wherein the terminal determines an access network to request to deregister based on the priority of the access network.
15. 9. The method of claim 8,

    Wherein the first identifier is a Globally Unique Temporary Identifier (GUTI) and the second identifier is a second GUTI.

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