Method for providing subscription information about non-public network to terminal

Abstract

The present disclosure relates to a communication technology and a system thereof that combines a 5G communication system that supports a higher data transmission rate than a 4G system with an IoT technology. The present invention can be applied to smart services (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retailers, safety and security related services, etc.) based on 5G communication technology and IoT related technologies. A method for providing subscription information about a non-public network to a terminal in a wireless communication system is disclosed.

Description

Technical Field

[0001] For a private communication network that operates locally in a smart factory or the like to provide communication services, a locally operated private cellular network (private network or non-public network or NPN) configured separately from a public, public cellular network is considered.

[0002] In particular, if a terminal moves between several private cellular networks, when the terminal attempts to use each private cellular network, a solution for pre-providing subscription data for accessing the private cellular network is required for the terminal. Background Art

[0003] In order to meet the demand for wireless data services that tend to increase after the commercialization of 4G communication systems, efforts are being made to develop enhanced 5G communication systems or quasi-5G (pre-5G) communication systems. For this reason, 5G communication systems or pre-5G communication systems are called super 4G network communication systems or post-LTE systems. In order to achieve high data transmission rates, it is considered to implement 5G communication systems in mmWave bands (e.g., 60Giga (60GHz) bands). In 5G communication systems, in order to reduce the path loss of radio waves and increase the transmission distance of radio waves in millimeter wave bands, beamforming, massive multiple input multiple output, full-dimensional multiple input multiple output (FD-MIMO), array antennas, analog beamforming and massive antenna technology are being discussed. In addition, in 5G communication systems, in order to improve the network of the system, technologies such as improved small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device-to-device communication (D2D), wireless backhaul, mobile networks, cooperative communications, coordinated multi-point (CoMP) and reception interference elimination are being developed. In addition, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) as advanced coding modulation (ACM) schemes and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies are being developed in 5G systems.

[0004] At the same time, the Internet has also evolved from a human-centered connection network (on which people generate and consume information) to the Internet of Things (IoT), in which information is exchanged and processed between distributed elements (such as objects) through the Internet of Things (IoT). Internet of Everything (IoE) technology, which combines big data processing technology connected to cloud servers with IoT technology, is emerging. In order to realize IoT, technical elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology and security technology are required. Therefore, technologies for connection between objects such as sensor networks, machine-to-machine (M2M) and machine type communication (MTC) are being studied recently. In the IoT environment, smart Internet technology (IT) services can be provided in which new value is created for human life by collecting and analyzing data generated by connected objects. IoT can be applied to fields such as smart homes, smart buildings, smart cities, smart cars or car networks, smart grids, health care, smart home appliances and advanced medical services by integrating and combining existing information technology (IT) and various industries.

[0005] Therefore, various attempts are being made to apply 5G communication systems to IoT. For example, technologies such as sensor networks, machine-to-machine (M2M), and machine-type communications (MTC) are implemented through schemes such as beamforming, MIMO, and array antennas (i.e., 5G communication technologies). Cloud Radio Access Network (Cloud RAN), as an application of the above-mentioned big data processing technology, can be said to be an example of the integration of 5G technology and IoT technology.

[0006] Recently, with the development of Long Term Evolution (LTE) and LTE-Advanced, if a terminal moves between several private cellular networks, when the terminal attempts to use each private cellular network, a method of providing the terminal with subscription data for accessing the private cellular network in advance is required. Summary of the invention

[0007] Technical issues

[0008] For a private communication network that is locally operated to provide communication services in a smart factory or the like, the present disclosure considers locally operating a private cellular network (private network or non-public network or NPN) configured separately from an ordinary public cellular network.

[0009] The private cellular network may include a private cellular network using a public cellular network in the form of a public network integrated NPN (or non-independent NPN) and a cellular network in the form of an independent NPN, depending on its operation method, the public cellular network being composed of a data network name (DNN) or a network slice instance of the public cellular network, and the cellular network in the form of an independent NPN being autonomously operated by the private cellular network without being associated with the public cellular network. Alternatively, there may be a cellular network in the form of an independent NPN operated by a public cellular network operator.

[0010] If a terminal needs to access multiple private cellular networks when moving, the content of the required subscription data needs to be provided in advance and stored in the unified data management (UDM) or unified data repository (UDR) of the terminal and the corresponding private cellular network according to the type of private cellular network to be accessed by the terminal. The present disclosure discloses a solution for an application function (AF) operated by an NPN service provider, a smart factory operator, etc. to provide the subscription data required for a private cellular network to the UDM or UDR and delete the subscription data, and a solution for providing the subscription data (NPN subscription data) of the private cellular network to the corresponding terminal and deleting the subscription data.

[0011] Technical Solution

[0012] In an embodiment according to the present disclosure for solving problems such as the above, a method performed by a UE in a mobile communication system includes: selecting a first independent non-public network (SNPN) to be accessed based on information about the SNPN broadcast by a base station; sending a registration request message for accessing the selected first SNPN to a network entity of the first SNPN; sending a packet data unit (PDU) session request to the network entity requesting to establish a PDU session with the first SNPN; receiving SNPN subscription data including subscription credentials of the UE for a second SNPN from the network entity through the PDU session established in response to the PDU session request message; releasing registration with the first SNPN; selecting a second SNPN to be accessed based on the received SNPN subscription data; and being registered to the second SNPN by performing authentication on the second SNPN based on the subscription credentials.

[0013] In another embodiment according to the present disclosure for solving problems such as the above, a method performed by a network entity of a first independent non-public network (SNPN) in a mobile communication system includes: receiving a registration request message for accessing a first SNPN from a UE; completing the registration of the UE based on the registration request message; receiving a packet data unit (PDU) session request message from the UE requesting to establish a PDU session with the first SNPN; establishing a PDU session in response to the PDU session request message; sending SNPN subscription data including the UE's subscription credentials for a second SNPN to the UE through the PDU session established in response to the PDU session request message; and releasing the registration of the UE. The UE selects the first SNPN to be accessed based on information about the first SNPN broadcast by the base station of the first SNPN. The UE selects the second SNPN to be accessed based on the SNPN subscription data sent to the UE, and registers to the second SNPN by performing authentication on the second SNPN based on the subscription credentials.

[0014] In another embodiment of the present disclosure for solving problems such as the above, a UE of a mobile communication system includes: a transceiver for sending and receiving signals and a controller connected to the transceiver. The controller is configured to: select a first independent non-public network (SNPN) to be accessed based on information about the SNPN broadcast by a base station; send a registration request message for accessing the selected first SNPN to a network entity of the first SNPN; send a packet data unit (PDU) session request message to the network entity requesting to establish a PDU session with the first SNPN; receive SNPN subscription data from the network entity through a PDU session established in response to the PDU session request message, the subscription data including subscription credentials for a UE of a second SNPN; release registration to the first SNPN; select a second SNPN to be accessed based on the received SNPN subscription data and register to the second SNPN by performing authentication on the second SNPN based on the subscription credentials.

[0015] In another embodiment of the present disclosure for solving problems such as those described above, a network entity of a first independent non-public network (SNPN) of a mobile communication system includes: a transceiver for sending and receiving signals and a controller connected to the transceiver. The controller is configured to: receive a registration request message for accessing a first SNPN from a UE; complete the registration of the UE based on the registration request message; receive a packet data unit (PDU) session request message requesting to establish a PDU session with the first SNPN from the UE; establish a PDU session in response to the PDU session request message; send SNPN subscription data including the subscription credentials of the UE for a second SNPN to the UE through the PDU session established in response to the PDU session request message; and release the registration of the UE. The UE selects the first SNPN to be accessed based on information about the first SNPN broadcast by the base station of the first SNPN. The UE selects the second SNPN to be accessed based on the SNPN subscription data sent to the UE, and registers to the second SNPN by performing authentication on the second SNPN based on the subscription credentials.

[0016] Beneficial technical effects

[0017] If the private cellular network that the UE needs to access is fixed, it is only necessary to pre-store the corresponding subscription data in the UDR or UDM of the UE and the private cellular network. However, if the private cellular network that the UE needs to access changes in various ways as the UE moves, it is necessary to provide and store the corresponding subscription data in the UDR or UDM of the UE and the cellular network as appropriate. In addition, if necessary, the stored subscription data may need to be deleted.

[0018] The effect of the present disclosure is that by providing the following scheme, the UE can use the NPN service consistently and smoothly even though the private cellular network that the UE needs to access is changed, wherein the scheme is used to provide the NPN subscription data of each UE to the UDM or UDR and the UE and delete the NPN subscription data according to the form of the private cellular network. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a private communication network architecture with public NW integrated NPN form.

[0020] Figure 2 It is a private communication network architecture with independent NPN form.

[0021] Figure 3 is a diagram illustrating the process of adding NPN subscription data to UDM and UDR.

[0022] Figure 4 is a diagram illustrating the process of adding NPN subscription data to a UDR.

[0023] Figure 5is a diagram illustrating a process of provisioning NPN subscription data to a UE.

[0024] Figure 6 is a diagram illustrating a process of provisioning NPN subscription data to a UE.

[0025] Figure 7 is a diagram illustrating a process of acquiring updated NPN subscription data by a UE when the UE accesses a standalone NPN autonomously operated by a private cellular network without associating with a public cellular network.

[0026] Figure 8 is a diagram illustrating a structure of a UE according to an embodiment of the present disclosure.

[0027] Fig. 9 is a diagram illustrating a structure of a network entity according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, when describing the present disclosure, if it is considered that a detailed description of a related known function or configuration makes the subject matter of the present disclosure unnecessarily ambiguous, it will be omitted. In addition, the terms to be described below are defined in consideration of the functions in the present disclosure and may differ according to the intention or practice of the user, operator. Therefore, each term should be defined based on the content of the entire specification.

[0029] By combining the embodiments described in detail with the accompanying drawings, the advantages and features of the present disclosure and the methods for achieving the advantages and features will become clearer. However, the present disclosure is not limited to the disclosed embodiments, but can be implemented in various ways. The embodiments are provided only to complete the present disclosure and enable those skilled in the art to fully understand the scope of the present disclosure. The present disclosure is limited by the categories of the claims. Throughout the specification, the same reference numerals will be used to refer to the same or similar elements.

[0030] Figure 1 is a diagram illustrating a private communication network architecture in the form of a public NW integrated NPN (PNI-NPN, PNI non-public network).

[0031] refer to Figure 1 , a private communication network architecture with a public NW integrated NPN form has the following form, in which some of the public cellular networks composed of data network names (DNNs) or network slice instances of the public cellular network are used for NPN.

[0032] Therefore, as in a public network, when accessing a private cellular network in the form of a public NW integrated NPN, the UE 110 sends information of a single network slice selection assistance information (S-NSSAI(s)) to the core network (CN) in order to access the network slice instance, and selects an access and mobility management function (AMF) 120 that can serve the S-NSSAI sent by the UE 110. The selected AMF 120 selects a session management function (SMF) 130 corresponding to the S-NSSAI(s) information. The SMF provides the corresponding NPN service, such as by selecting a user plane function (UPF) 140 corresponding to the network slice instance or DNN.

[0033] Meanwhile, in order to control access of UEs in a specific area or cell, RAN 105 may use a method of broadcasting information of a Closed Access Group (CAG) ID served by the RAN and accessing the RAN broadcasting the CAG ID only to UEs subscribed to the CAG ID.

[0034] The CN includes entities such as the AMF 120 responsible for mobility management and registration management of the UE, an authentication server function (AUSF) (not shown) responsible for authenticating the UE, a unified data management (UDM) 150 that manages subscriptions, a unified data repository (UDR) that stores subscription data, an SMF 130 responsible for session management, a UPF 140 that forwards user data, an application function (AF) 180, and a network exposure function (NEF) 170, wherein the application function (AF) 180 is an application server operated by a service provider for providing NPN services outside the CN, and the network exposure function (NEF) 170 is responsible for exposing the information of the CN to the outside of the network and providing the information required by the CN by the AF.

[0035] Figure 2 is a diagram illustrating a private communication network architecture in the form of a separate NPN (SNPN).

[0036] refer to Figure 2 , there is a cellular network in the form of an independent NPN, which is operated autonomously by a private cellular network without being associated with a public cellular network. Alternatively, there may be a cellular network in the form of an independent NPN operated by a public cellular network operator.

[0037] exist Figure 2 , the independent NPN#3 230 is a cellular network having an independent NPN form that is autonomously operated by a private cellular network without being associated with a public cellular network. Each of the independent NPN#1 210 and NPN#2 220 is a cellular network having an independent NPN form that is operated by a public cellular network operator.

[0038] Like the independent NPN #3 230, the independent NPN operated autonomously by a private cellular network without being associated with a public cellular network has the same communication network architecture as the public cellular network. In this case, the 5G-RAN 235 can broadcast the MCC information of the PLMN ID and the NPN ID of the independent NPN by setting the MCC information to a specific value. For example, the MCC 999 value is used.

[0039] On the contrary, like independent NPN #1 210 and NPN #2 220, in the case where the cellular network has a cellular network in the form of an independent NPN operated by a public cellular network operator, the UDM 205 and the AUSF (not shown) use entities in the public cellular network. In addition, if the independent NPN wants to have its own UDR or NEF as the case may be, the UDR 211, 221 or the NEF 212, 222 can be located in the independent NPN. In addition to the entity, the independent NPN is autonomously composed of a separate independent entity and has the same architecture as the public cellular network. In this case, the 5G-RAN broadcasts the PLMN ID of the corresponding public cellular network and the NPN ID of the independent NPN.

[0040] Meanwhile, AF 208, an application server operated by a service provider for providing NPN services outside the CN, may provide information required by the NPN through the NEF or may be provided with the information within the NPN.

[0041] According to an embodiment of the present disclosure, the NPN subscription data of the UE may include different information according to the form of the NPN to be accessed by the UE.

[0042] That is to say, if Figure 1 In the case of an NPN in the form of a public NW integrated NPN, the contents of some or all of the following items are included in the NPN subscription data.

[0043] - UE's Subscription Permanent Identifier (SUPI)

[0044] - The UE's Universal Public Subscription Identifier (GPSI)

[0045] - List of allowed Closed Access Groups (CAGs) or a list of allowed CAG IDs that can be accessed by the UE. In this case, the PLMN ID may also be included.

[0046] – An indication indicating whether the UE can only be accessed in allowed CAG cells.

[0047] – List of Single Network Slice Selection Assistance Information (S-NSSAI) that the UE can use for NPN

[0048] – Data Network Name (DNN) that the UE can use for NPN

[0049] – A human-readable network name that the UE can use for the NPN. For example, a human-readable network name corresponding to each S-NSSAI or each DNN, or mapping information between an S-NSSAI and a human-readable network name, or mapping information between a DNN and a human-readable network name

[0050] – The period during which the NPN subscription data is valid:

[0051] For example, the time period may indicate information about a time period (hours or days or weeks or months or years) in which the NPN subscription data is available, a time when the NPN subscription data expires, etc. For example, the value may indicate always valid or not always valid by inputting 0 or a specific value (such as null). The valid time period may be given for all NPN subscription data or may be given for each item of NPN subscription data. For example, the valid time period may be set for each allowed CAG ID or for each DNN or for each S-NSSAI or for each human-readable network name.

[0052] –NPN subscription data change indicator. That is, this indicator indicates that the NPN subscription data of the serving AMF or UE needs to be updated because the NPN subscription data has been changed.

[0053] like Figure 2 In the case of an NPN in the form of an independent NPN, the contents of some or all of the following items are included in the NPN subscription data.

[0054] - UE's Subscription Permanent Identifier (SUPI)

[0055] - The UE's Universal Public Subscription Identifier (GPSI)

[0056] - A list of NPN IDs that the UE can access. In this case, the PLMN ID may also be included.

[0057] - For each NPN (or for each NPN ID), the subscription credentials used for authentication when the UE accesses the corresponding NPN.

[0058] – Human-readable network name of the NPN available to the UE.

[0059] – The period during which the NPN subscription data is valid:

[0060] For example, the time period may indicate information about a time period (hours or days or weeks or months or years) in which the NPN subscription data is available, a time when the NPN subscription data expires, etc. For example, the value may indicate always valid or not always valid by inputting 0 or a specific value (such as null). The valid time period may be given for all NPN subscription data or may be given for each item of NPN subscription data. For example, the valid time period may be set for each NPN ID or each PLMN ID+NPN ID or each human-readable network name.

[0061] –NPN subscription data change indicator. That is, this indicator indicates that the NPN subscription data of the UE needs to be updated because the NPN subscription data has changed.

[0062] In this document, the NPN subscription data mentioned in describing the embodiments refers to the NPN subscription data of an NPN having a public NW integrated NPN form or an independent NPN form.

[0063] Figure 3 is a diagram illustrating a process of adding NPN subscription data to UDM and UDR according to an embodiment of the present disclosure.

[0064] If the NPN subscription data of the UE is to be added or modified for the NPN to be accessed by the AF operated by the NPN service provider, smart factory operator, etc., in step 1, the AF sends the NPN subscription data to the NEF of the PLMN of the corresponding NPN operating the corresponding NPN. In this case, the AF may use the Nnef_ParameterProvision_Update request message (301). In this case, the Nnef_ParameterProvision_Update request message may include, in addition to the NPN subscription data, a GPSI or SUPI for providing a notification of which UE the message is for, and may include an AF ID for indicating a source providing the NPN subscription data or an AF-Service-Identifier indicating that the NPN subscription data is provided, and may include a transaction reference ID previously shared between the AF and the NEF.

[0065] In step 2, the NEF receiving the Nnef_ParameterProvision_Update request message sends the NPN subscription data to the UDM in order to update the NPN subscription data information. In this case, the NEF may use the Nudm_ParameterProvision_Update request message (302). In this case, the Nudm_ParameterProvision_Update request message may contain, in addition to the NPN subscription data, a GPSI or SUPI for providing a notification of which UE the message is for, may contain an AF ID for indicating a source providing the NPN subscription data or an AF-Service-Identifier indicating that the NPN subscription data is provided, and may contain a transaction reference ID previously shared between the NE and the UDM.

[0066] In step 3, the UDM having received the Nudm_ParameterProvision_Update request message sends a Nudr_DM_Query request message to the UDR to check whether the UDR needs to be updated for the received NPN subscription data (303). In this case, the Nudr_DM_Query request message may have a data set identifier set to "NPN subscription data", or corresponding information including a data set identifier containing the NPN subscription data may be received from the UDR.

[0067] In step 4, the UDM determines whether the NPN subscription data of the UDR needs to be updated (304). For example, when the NPN subscription data received from the UDR through step 3 is different from the NPN subscription data received from the NEF, the UDM recognizes that the UDR needs to be updated or does not perform step 3 or recognizes that the UDR is updated using the NPN subscription data received from the NEF regardless of the information received in step 3.

[0068] In step 5, the UDM sends a Nudr_DM_Update request message to the UDR to update the NPN subscription data (305). In this case, the Nudr_DM_Update request message has a data set identifier set to "NPN subscription data", contains a data set identifier containing the NPN subscription data and contains information corresponding to the NPN subscription data or data set identifier that needs to be updated.

[0069] Thereafter, the result indicating that the updating of the NPN subscription data has been successfully performed is notified to the AF through steps 6 and 7 (306 and 307).

[0070] Meanwhile, when the valid period included in the information expires, the NPN subscription data stored in the UDM or UDR is automatically destroyed. Alternatively, in order to destroy the NPN subscription data, the AF may notify the UDM of the deletion of the corresponding NPN subscription data by using a method of setting the content of the NPN subscription data to "null" or indicating that the valid period included in the NPN subscription data is not always valid in steps 1 and 2. The UDM may set the Nudr_DM_Delete request message to the data set identifier = "NPN subscription data" instead of the Nudr_DM_Update request message in step 5, and may send the Nudr_DM_Delete request message to the UDR so that the UDR deletes the NPN subscription data.

[0071] Figure 4 is a diagram illustrating a process of adding NPN subscription data to a UDR according to an embodiment of the present disclosure.

[0072] If the NPN subscription data of the UE is to be added or modified for the NPN accessed by the AF operated by the NPN service provider, smart factory operator, etc., then in step 1, the AF sends the NPN subscription data to the NEF of the PLMN or the NEF of the corresponding NPN operating the corresponding NPN (401). In this case, the Nnef_ServiceParameter_Create request message may be used to newly add the NPN subscription data, or the Nnef_ServiceParameter_Update request message may be used to update the existing NPN subscription data. In this case, the Nnef_ServiceParameter_Create request or the Nnef_ServiceParameter_Update request message may include, in addition to the NPN subscription data, a GPSI or SUPI for providing a notification of which UE the message is for, may include an AF ID for indicating a source providing the NPN subscription data or include an AF-Service-Identifier indicating that the NPN subscription data is provided, and in the case of the Nnef_ServiceParameter_Create request message, may include a transaction reference ID previously shared between the AF and the NEF.

[0073] In step 2, the NEF that receives the Nnef_ServiceParameter_Create request message or the Nnef_ServiceParameter_Update request message directly sends the NPN subscription data to the UDR to update the NPN subscription data information. In this case, the NEF may use the Nudr_DM_Create request message or the Nudr_DM_Update request message (402).

[0074] In this case, if NPN subscription data is newly added, the Nudr_DM_Create request message has a data set identifier set to "NPN subscription data" or contains a data set identifier containing NPN subscription data or includes the NPN subscription data to be updated or information corresponding to the data set identifier.

[0075] If the existing NPN subscription data is updated, the Nudr_DM_Update request message has a data set identifier set to "NPN subscription data" or contains a data set identifier containing the NPN subscription data or contains the NPN subscription data to be updated or information corresponding to the data set identifier.

[0076] Thereafter, the AF is notified of a result indicating whether the update of the NPN subscription data has been successfully performed through steps 3 and 4 ( 403 and 404 ).

[0077] Figure 5 is a diagram illustrating a process of supplying NPN subscription data to a UE according to an embodiment of the present disclosure.

[0078] According to reference Figure 3 and Figure 4 In the described embodiment, in the case where the UE is registered to a network of a public network, i.e., a PLMN, if the NPN subscription data of the UDM of the UE has been changed or the NPN subscription data of the UDR has been changed and as a result, the NPN subscription data of the UDM has been changed, if the newly changed NPN subscription data is applied to the subscription of the corresponding PLMN, the UE environment of the AMF is updated with the corresponding NPN subscription data and provided to the UE. The NPN subscription data of the NPN in the form of a public NW integrated NPN corresponds to this case. Alternatively, the NPN subscription data of the NPN in the form of an independent NPN operated by a public network, i.e., a PLMN operator may correspond to this case.

[0079] In step 0, if the NPN subscription data has been updated, the AMF may request a subscription service (500) from the UDM, which subscription service requests notification. To this end, the Nudm_SDM_Subscribe request message includes SUPI to inform the UDM of information on which UE the message corresponds to. In order to request notification when the NPN subscription data changes, a subscription data type or NPN subscription data may be included in the message, wherein the subscription data type includes a subscription data type (="NPN subscription data)".

[0080] As another method for the UDM to recognize that the NPN subscription data has been updated, if an NPN subscription data change indicator is included in the subscription data of the UE, the UDM may recognize that the NPN subscription data has been updated.

[0081] According to reference Figure 3 and Figure 4 In the described embodiment, when the NPN subscription data of the UDM corresponding to the UE is changed, in step 1, the UDM notifies the AMF that the NPN subscription data has been changed and sends a Nudm_SDM_Notification notification message to send the changed NPN subscription data (501). The Nudm_SDM_Notification notification message includes a SUPI to indicate which UE's subscription data the message corresponds to. In order to provide a notification that the NPN subscription data is included, the updated NPN subscription data and a subscription data type = "NPN subscription data" or a subscription data type including the NPN subscription data may be included in the message.

[0082] In step 2, the AMF receiving the updated NPN subscription data recognizes that the UE configuration needs to be updated (502), and sends a UE configuration update command message to the UE as in step 3 when the state of the UE is the connected state (503). Alternatively, when the state of the UE is the idle state, the AMF changes the state of the UE to the connected state by paging, or in the case of a UE in MICO mode, when the state of the UE changes to the connected state, sends a UE configuration update command message to the UE as in step 3. The UE configuration update command message includes the NPN subscription data. In step 4, the UE notifies the AMF that the NPN subscription data has been successfully delivered through a UE configuration update complete message (504).

[0083] In addition, in step 5, the AMF notifies the UDM through a Nudm_SDM_Info service message that the NPN subscription data has been successfully delivered to the UE (505). The Nudm_SDM_Info service message includes a confirmation providing a notification that the SUPI and NPN subscription data of the corresponding UE have been successfully delivered.

[0084] Meanwhile, in step 6, for the case where the UE applies the newly changed NPN subscription data, the AMF sends the required updated information to the (R)AN that the UE is accessing (506). For example, in the case of NPN subscription data in which an NPN in the form of a public NW integrated NPN is present, mobility restriction information in which allowed CAG list information and the like have been updated may be included and delivered as update information.

[0085] Figure 6 is a diagram illustrating a process of providing NPN subscription data to a UE according to an embodiment of the present disclosure.

[0086] According to reference Figure 3 and Figure 4In the described embodiment, in the case where the UE is registered with a network of a public network, i.e., a PLMN, if the NPN subscription data of the UDM of the UE has been changed or the NPN subscription data of the UDM has been changed because the NPN subscription data of the UDR has been changed, if the newly changed NPN subscription data has not been applied to the subscription of the corresponding PLMN, the corresponding NPN subscription data is provided to the UE. For an NPN in the form of an independent NPN operated by an operator of the public network, i.e., the PLMN, the NPN subscription data may correspond to the corresponding NPN subscription data.

[0087] In step 0, when the NPN subscription data is updated in the UDM, the AMF may request a subscription service (600) from the UDM, where the subscription service requests notification. To this end, the Nudm_SDM_Subscribe request message contains SUPI to inform the UDM of the information of which UE the message corresponds to. In order to indicate a request for notification when the NPN subscription data is changed, a subscription data type = "NPN subscription data" or a subscription data type containing the NPN subscription data may be included in the message.

[0088] As another method for the UDM to identify that the NPN subscription data has been updated, if the subscription data of the UE includes an NPN subscription data change indicator, the UDM may identify that the NPN subscription data has been updated.

[0089] According to reference Figure 3 and Figure 4 In the described embodiment, when the NPN subscription data of the UDM corresponding to the UE has been changed, in step 1, the UDM notifies the AMF that the NPN subscription data has been changed so as to provide the UE with the NPN subscription data, and sends a Nudm_SDM_Notification notification message so as to send the changed NPN subscription data (601). The Nudm_SDM_Notification notification message contains the SUPI so as to indicate which UE's subscription data the NPN subscription data is. In addition, the UDM sends the NPN subscription data together with the SUPI to the AMF by inserting the updated NPN subscription data into a transparent container, so as to send the NPN subscription data to the UE together with the subscription data type = "NPN subscription data" or the subscription data type including the NPN subscription data.

[0090] In step 2, the AMF that has received the Nudm_SDM_Notification notification message recognizes that the information contained in the transparent container needs to be delivered to the corresponding UE. When the UE state is connected, the AMF sends a DL NAS transport message to the UE by carrying a transparent container including NPN subscription data on the DL NAS transport message (602). Alternatively, when the UE state is idle, the AMF changes the UE state to a connected state through paging, or sends a DL NAS transport message to the UE when the UE state is changed to a connected state in the case of the UE's MICO mode. In step 3, the UE notifies the AMF through a UL NAS transport message that the transparent container containing the NPN subscription data has been successfully delivered (603).

[0091] In addition, in step 4, the AMF notifies the UDM through a Nudm_SDM_Info service message that the transparent container including the NPN subscription data has been successfully delivered to the UE (604). The Nudm_SDM_Info service message includes providing the following confirmation, which provides a notification that the transparent container including the SUPI and the NPN subscription data of the corresponding UE has been successfully delivered.

[0092] Figure 7 is a diagram illustrating a process of acquiring updated NPN subscription data by a UE when the UE accesses a standalone NPN autonomously operated by a private cellular network during a period without association with a public cellular network according to an embodiment of the present disclosure.

[0093] According to reference Figure 3 and Figure 4 In the described embodiment, when the NPN subscription data of the UE is changed in the UDM or UDR of an independent NPN operated autonomously by a private cellular network without being associated with a public cellular network, if the UE subscribes to the independent NPN, the UE can change the NPN subscription data during or after the registration process by Figure 5 The method obtains the changed NPN subscription data.

[0094] However, if the UE does not subscribe to the independent NPN but the independent NPN supports non-authenticated access, the UE can Figure 7 The process of accessing the independent NPN through non-authentication access to obtain NPN subscription data.

[0095] In step 0a, according to the reference Figure 3 and 4 In the described embodiment, the AF provides the changed NPN subscription data of the UE to the UDM or UDR (700a) of a standalone NPN operated autonomously by a private cellular network without association with a public cellular network.

[0096] At the same time, the independent NPN can support non-authentication registration, that is, non-authentication network registration, so as to provide a method for UE that has not obtained NPN subscription to obtain the required NPN subscription by accessing the independent NP.

[0097] In step 0b, the RAN of the standalone NPN (SNPN) broadcasts the PLMN ID (MCC=999) and NPN ID to inform the UE of the NW identity of the SNPN. The broadcast may include an indication indicating that the SNPN supports unauthenticated network registration (or a restricted local operator service (RLOS) indication) (700b).

[0098] If the UE does not have the credentials and subscription of the SNPN, when the UE wants to access the SNPN and identifies that the SNPN supports non-authentication network registration, the UE NW-selects the SNPN (701). The UE can find out whether the SNPN supports non-authentication network registration from the "indication indicating that the SNPN supports non-authentication network registration" broadcast by the RAN of the SNPN, or can always identify that the SNPN supports non-authentication network registration when MCC=999.

[0099] The UE selects a SNPN. In step 2, for non-authentication network registration to the SNPN, the UE includes an RLOS indication in the registration request message, sends a registration request message to the AMF and completes the non-authentication network registration (702). In step 3, the UE requests a PDU session. In this case, the request message may include an RLOS indication (703). At the same time, the AMF that has received the PDU session request message selects an SMF that supports secondary authentication and forwards the message to the selected SMF. When it is identified that secondary authentication is required, the SMF that has received the PDU session request message discovers the Data Network Authentication Authorization and Accounting (DN AAA) server and starts the authentication process with the discovered DN AAA server.

[0100] As a method of identifying the need for auxiliary authentication, when the AMF sends a Nsmf_PDUSession_CreateSMContext request message to the SM by including the PDU session request message received from the non-authenticated network registered UE into the Nsmf_PDUSession_CreateSMContext request message, the SMF refers to the RLOS indication contained in the PDU session request message or indicates that the PDU session requires auxiliary authentication by including the UE's status as a RLOS indication or a non-authenticated status.

[0101] In step 4, the UE performs an Extensible Authentication Protocol (EAP) authentication process with the DN AAA server through the SMF (704). When the EAP authentication is successfully completed, in step 5, the UE terminates the establishment of the PDU session (705).

[0102] In the EAP authentication step of step 4, the UE pre-shares credentials, through which the SNPN operator and the smart factory operating the DN AAA server can mutually authenticate each other. For example, the SNPN operator and the smart factory can be authenticated by using an ID / password or a certificate.

[0103] In step 6, the UE accesses the AF or application server from which the UE's SNPN subscription data and credentials can be downloaded through the generated PDU session, downloads the UE's SNPN subscription data and credentials, and installs the SNPN subscription data and credentials therein (706).

[0104] In step 7, the UE in which the new SNPN subscription data and credentials have been installed performs deregistration on the now accessed SNPN in order to access the SNPN by using the newly downloaded SNPN subscription data and credentials (707). In step 8, the UE accesses the SNPN again by using the newly allocated SNPN subscription data and credentials (708).

[0105] Figure 8 is a diagram illustrating a structure of a UE according to an embodiment of the present disclosure.

[0106] refer to Figure 8 , the UE may include a transceiver 810, a controller 820, and a storage unit 830. In the present disclosure, the controller 820 may be defined as a circuit or an application specific integrated circuit or at least one processor.

[0107] The transceiver 810 may transmit and receive signals to and from another network entity. For example, the transceiver 810 may receive system information from a base station and may receive a synchronization signal or a reference signal.

[0108] According to the embodiments proposed in the present disclosure, the controller 820 may control the overall operation of the UE. For example, the controller 820 may control the signal flow between blocks, thereby performing the operations according to the described flowcharts.

[0109] The storage unit 830 may store at least one of information transmitted and received by the transceiver 810 and information generated by the controller 820 .

[0110] Fig. 9 is a diagram illustrating a structure of a network entity according to an embodiment of the present disclosure.

[0111] Fig. 9 express Figures 1 to 7 Any of the network entities shown in . Fig. 9 , the network entity may include a transceiver 910, a controller 920, and a storage unit 930. In the present disclosure, the controller 920 may be defined as a circuit or an application specific integrated circuit or at least one processor.

[0112] The transceiver 910 may transmit and receive signals to and from the UE or another network entity. For example, the transceiver 910 may transmit system information to the UE and may transmit a synchronization signal or a reference signal.

[0113] According to the embodiments proposed in the present disclosure, the controller 920 may control the overall operation of the network entity. For example, the controller 920 may control the signal flow between blocks, thereby performing the operations according to the described flowcharts.

[0114] The storage unit 930 may store at least one of information transmitted and received by the transceiver 910 and information generated by the controller 920 .

Claims

1. A method performed by a terminal in a mobile communication system, the method comprising: selecting a first independent non-public network (SNPN) to access based on information about the SNPN, wherein the information is broadcast from a base station; Sending a registration request message for accessing the selected first SNPN to a network entity of the first SNPN; Sending a packet data unit (PDU) session request message to the network entity requesting to establish a PDU session with the first SNPN; receiving, from the network entity, via the PDU session established in response to the PDU session request message, SNPN subscription data including subscription credentials of the terminal for a second SNPN; releasing the registration of the first SNPN; selecting the second SNPN to be accessed based on the received SNPN subscription data; and Authentication is performed on the second SNPN based on the subscription credentials to register with the second SNPN.

2. The method according to claim 1, in, The PDU Session Request message includes a Restricted Local Operator Service (RLOS) indicator, and The PDU session is established based on the PDU session request message.

3. The method of claim 1, wherein: The PDU session is established after the network authentication server authenticates the terminal.

4. The method of claim 1, wherein: The network entity includes an Access and Mobility Management Function (AMF).

5. A method performed by a network entity of a first independent non-public network (SNPN) in a mobile communication system, the method comprising: receiving, from a terminal, a registration request message for accessing the first SNPN; completing registration of the terminal based on the registration request message; receiving, from the terminal, a packet data unit (PDU) session request message requesting to establish a PDU session with the first SNPN; Establishing a PDU session in response to the PDU session request message; sending, to the terminal, SNPN subscription data including subscription credentials of the terminal for a second SNPN, via the PDU session established in response to the PDU session request message; and releasing the registration of the terminal, wherein the terminal selects the first SNPN to be accessed based on information about the first SNPN broadcasted from the base station of the first SNPN, and The terminal selects the second SNPN to be accessed based on the SNPN subscription data sent to the terminal and registers to the second SNPN by authenticating on the second SNPN based on the subscription credential.

6. The method according to claim 5, in, The PDU Session Request message includes a Restricted Local Operator Service (RLOS) indicator, and The PDU session is established based on the PDU session request message.

7. The method of claim 5, wherein: Establishing a PDU session includes: establishing the PDU session when the terminal is authenticated by a network authentication server, and The network entity includes an access and mobility management function (AMF).

8. A terminal of a mobile communication system, the terminal comprising: a transceiver configured to transmit and receive signals; and A controller is coupled to the transceiver and is configured to: selecting a first independent non-public network (SNPN) to access based on information about the SNPN, wherein the information is broadcast from a base station; Sending a registration request message for accessing the selected first SNPN to a network entity of the first SNPN; Sending a packet data unit (PDU) session request message to the network entity requesting to establish a PDU session with the first SNPN; receiving, from the network entity, via the PDU session established in response to the PDU session request message, SNPN subscription data including subscription credentials of the terminal for a second SNPN; releasing the registration of the first SNPN; selecting the second SNPN to be accessed based on the received SNPN subscription data; and Authenticate on the second SNPN based on the subscription credentials to register with the second SNPN.

9. The terminal according to claim 8, in, The PDU Session Request message includes a Restricted Local Operator Service (RLOS) indicator, and The PDU session is established based on the PDU session request message.

10. The terminal according to claim 8, wherein: The PDU session is established after the network authentication server authenticates the terminal.

11. The terminal according to claim 8, wherein: The network entities include an Access and Mobility Management Function (AMF).

12. A network entity of a first independent non-public network (SNPN) of a mobile communication system, the network entity comprising: a transceiver configured to transmit and receive signals; and A controller is coupled to the transceiver and is configured to: receiving, from a terminal, a registration request message for accessing the first SNPN; completing registration of the terminal based on the registration request message; receiving, from the terminal, a packet data unit (PDU) session request message requesting to establish a PDU session with the first SNPN; Establishing a PDU session in response to the PDU session request message; sending, to the terminal, SNPN subscription data including subscription credentials of the terminal for a second SNPN, via the PDU session established in response to the PDU session request message; and releasing the registration of the terminal, wherein the terminal selects the first SNPN to be accessed based on information about the first SNPN broadcasted from the base station of the first SNPN, and The terminal selects the second SNPN to be accessed based on the SNPN subscription data sent to the terminal and registers to the second SNPN by authenticating on the second SNPN based on the subscription credential.

13. The network entity according to claim 12, in, The PDU Session Request message includes a Restricted Local Operator Service (RLOS) indicator, and The PDU session is established based on the PDU session request message.

14. The network entity according to claim 12, wherein: The controller is configured to establish the PDU session when the terminal is authenticated by a network authentication server.

15. The network entity according to claim 12, wherein: The network entity includes an Access and Mobility Management Function (AMF).

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