Disabling N1 mode upon receiving 5GMM cause value message

Abstract

The present disclosure relates to disabling N1 mode after receiving a 5G Mobility Management (5GMM) cause value message. A method includes transmitting, by a user equipment (UE), a first message to a network node, the first message including a request to access a first network according to a non-access stratum (NAS) protocol. The UE receives a second message from the network node, the second message including an indication that no network slice is available for serving access to the first network requested by the UE. Based on receiving the second message, the capability to access the network using the NAS protocol is disabled by the UE, and an identity of the first network is stored, and after the storage, the stored identity of the first network is utilized by the UE during the network selection procedure.

Description

Technical Field

[0001] Various example embodiments relate generally to wireless networks, and more particularly to disabling N1 mode upon receiving a 5G Mobility Management (5GMM) cause value message. Background Art

[0002] In order to participate in 5G Mobility Management (5GMM), the user equipment (UE) registers with the network using the non-access stratum (NAS) protocol by sending a registration request message. The network informs the UE whether a network slice is available, and if a network slice is available, the UE's registration is allowed. If no network slice is available, the network responds to the UE's registration request with a registration reject message, in which case the UE may disable the N1 mode capability. However, unless another radio access technology (RAT) is provided to the UE, the UE will continue to re-enable the N1 mode capability and issue registration requests to the same network indefinitely, which may result in excessive use of resources. Summary of the invention

[0003] In one aspect of the present disclosure, a method includes sending, by a user equipment (UE) to a network node, a first message including a request to access a first network according to a non-access stratum (NAS) protocol. The UE receives a second message from the network node, the second message including an indication that no network slice is available to serve access to the first network requested by the UE. The UE disables an ability to access a network using the NAS protocol based on receiving the second message, stores an identity of the first network, and, after storing, utilizes the stored identity of the first network by the UE during a network selection process.

[0004] In one aspect of the method, the first message is a registration request message.

[0005] In one aspect of the method, the registration request message includes a request for one or more single network slice selection assistance information (S-NSSAI).

[0006] In one aspect of the method, the second message is a registration reject message.

[0007] In one aspect of the method, the indication that no network slice is available is a 5G System Mobility Management (5GMM) cause value #62 "No network slice is available" indication.

[0008] In one aspect of the method, disabling the ability to access the network using the NAS protocol includes disabling N1 mode capability.

[0009] In one aspect of the method, the method includes discarding, by the UE, a first network during a network selection procedure.

[0010] In one aspect of the method, the method includes deleting, by the UE based on an occurrence of a first event, a stored identity of the first network.

[0011] In one aspect of the method, the first event comprises expiration of a timer.

[0012] In one aspect of the method, the UE starts a timer after disabling the ability to access the network using the NAS protocol.

[0013] In one aspect of the method, the first event comprises receiving, by the UE, a third message from the network node.

[0014] In one aspect of the method, the third message includes an indication that registration with the first network is available for access by the UE.

[0015] In one aspect of the method, the third message includes an indication that the network slice subscription has been changed.

[0016] In one aspect of the method, the first event comprises the UE being turned off.

[0017] In one aspect of the method, the first event comprises removing a universal subscriber identity module from the UE.

[0018] In one aspect of the method, the first event comprises a modification to a subscriber data list.

[0019] In one aspect of the method, the stored identity is associated with an entry of the subscriber data list.

[0020] In one aspect of the method, the network node includes an Access and Mobility Function (AMF).

[0021] In one aspect of the present disclosure, a user equipment includes at least one processor and at least one memory storing instructions, and when the instructions are executed by the at least one processor, the user equipment performs at least any one of the above methods.

[0022] In one aspect of the present disclosure, a processor-readable medium stores instructions, which, when executed by at least one processor of a device, causes the device to perform at least any one of the above methods.

[0023] According to some aspects, the subject matter of the independent claims is provided. Some further aspects are defined in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Some example embodiments will now be described with reference to the accompanying drawings.

[0025] Figure 1 is a diagram of an example embodiment of wireless networking between a network system and a user equipment (UE) according to one illustrative aspect of the present disclosure;

[0026] Figure 2 is a diagram of example components of a network system according to one illustrative aspect of the present disclosure;

[0027] Figure 3 is a diagram of an example embodiment of signals and operations between a UE and an AMF according to one illustrative aspect of the present disclosure; and

[0028] Figure 4 is a diagram of an example embodiment of components of a UE or network device according to one illustrative aspect of the present disclosure. DETAILED DESCRIPTION

[0029] In the following description, certain specific details are set forth in order to provide a thorough understanding of the disclosed aspects. However, one skilled in the relevant art will recognize that the various aspects may be practiced without one or more of these specific details or using other methods, components, materials, etc. In other cases, well-known structures associated with transmitters, receivers, or transceivers are not shown or described in detail to avoid unnecessarily obscuring the description of the various aspects.

[0030] In this specification, reference to "one aspect" or "an aspect" indicates that a particular feature, structure, or characteristic described in conjunction with that aspect is included in at least one aspect. Thus, the appearance of the phrase "in one aspect" or "in an aspect" in various places in this specification does not necessarily refer to the same aspect. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more aspects.

[0031] The embodiments described in the present disclosure may be implemented in wireless network devices, such as, but not limited to, devices utilizing Worldwide Interoperability for Microwave Access (WiMAX), Global System for Mobile Communications (GSM, 2G), GSM EDGE Radio Access Network (GERAN), General Packet Radio Service (GRPS), Universal Mobile Telecommunications System (UMTS, 3G) based on basic Wideband Code Division Multiple Access (W-CDMA), High Speed ​​Packet Access (HSPA), Long Term Evolution (LTE), Advanced LTE, Enhanced LTE (eLTE), 5G New Radio (5GNR), Advanced 5G, 6G (and beyond), and 802.11ax (Wi-Fi 6) wireless network systems. The term "eLTE" herein refers to LTE evolution connected to a 5G core. LTE is also known as Evolved UMTS Terrestrial Radio Access (EUTRA) or Evolved UMTS Terrestrial Radio Access Network (EUTRAN).

[0032] The present disclosure may use the term "serving network device" to refer to a network node or network device (or a portion thereof) that serves a UE. As used herein, the terms "send to," "receive from," and "cooperate with" (and variations thereof) include communications that may or may not involve communications through one or more intermediate devices or nodes. The term "acquire" (and variations thereof) includes acquiring for the first time or reacquiring after the first acquisition. The term "connect" may refer to a physical connection or a logical connection.

[0033] The present disclosure uses 5G NR as an example of a wireless network, and may use a smartphone and / or an extended reality headset as an example of a UE. It should be understood that such examples are merely illustrative, and the present disclosure is applicable to other wireless networks and user equipment.

[0034] Figure 1 1 is a diagram depicting an example of wireless networking between a network system 100 and a user equipment (UE) 150. The network system 100 may include one or more network nodes 120, one or more servers 110, and / or one or more network devices 130 (e.g., test equipment). The network node 120 will be described in more detail below. As used herein, the term "network device" may refer to any component of the network system 100, such as a server 110, a network node 120, a network device 130, any (multiple) components of the above, and / or any (multiple) other components of the network system 100. Examples of network devices include, but are not limited to, devices that implement various aspects of 5G NR, etc. The present disclosure describes embodiments related to 5G NR and embodiments involving various aspects defined by the Third Generation Partnership Project (3GPP). However, it is conceivable that embodiments related to other wireless network technologies are also covered within the scope of the present disclosure.

[0035] The following description provides further details of an example of a network node. In a 5G NR network, a gNodeB (also referred to as a gNB) may include, for example, a node that provides new radio (NR) user plane and control plane protocol termination towards a UE and is connected to a 5G core (5GC) via an NG interface, for example in accordance with 3GPP TS 38.300 V16.6.0 (2021-06) Section 3.2, which is incorporated herein by reference.

[0036] The gNB supports various protocol layers, such as Layer 1 (L1) (ie, physical layer), Layer 2 (L2), and Layer 3 (L3).

[0037] NR’s Layer 2 (L2) is split into the following sublayers: Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP), and Service Data Adaptation Protocol (SDAP), where for example:

[0038] ○The physical layer provides the transport channel to the MAC sublayer;

[0039] ○The MAC sublayer provides logical channels to the RLC sublayer;

[0040] ○ The RLC sublayer provides RLC channels to the PDCP sublayer;

[0041] ○ The PDCP sublayer provides radio bearer to the SDAP sublayer;

[0042] ○The SDAP sublayer provides Quality of Service (QoS) flows to 5GC;

[0043] o Control channels include the Broadcast Control Channel (BCCH) and the Physical Control Channel (PCCH).

[0044] Layer 3 (L3) includes, for example, Radio Resource Control (RRC) in accordance with Section 6 of 3GPP TS 38.300 V16.6.0 (2021-06), which is incorporated herein by reference.

[0045] The gNB Central Unit (gNB-CU) includes, for example, a logical node that hosts, for example, the Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP) and Packet Data Convergence Protocol (PDCP) protocols of the gNB, or the RRC and PDCP protocols of the en-gNB, which controls the operation of one or more gNB Distributed Units (gNB-DUs). The gNB-CU terminates the F1 interface connected to the gNB-DU. The gNB-CU may also be referred to herein as a CU, a central unit, a centralized unit, or a control unit.

[0046] The gNB distributed unit (gNB-DU) includes, for example, a logical node that hosts the radio link control (RLC), media access control (MAC), and physical (PHY) layers of a gNB or en-gNB, and whose operation is partially controlled by the gNB-CU. One gNB-DU supports one or more cells. A cell is supported by only one gNB-DU. The gNB-DU terminates the F1 interface connected to the gNB-CU. The gNB-DU may also be referred to as a DU or distributed unit in this article.

[0047] As used herein, the term "network node" may refer to any one of a gNB, a gNB-CU, or a gNB-DU, or any combination thereof. A RAN (Radio Access Network) node or a network node (such as, for example, a gNB, a gNB-CU, or a gNB-DU, or a portion thereof) may be implemented using, for example, a device having at least one processor and / or at least one memory having processor-readable instructions ("program") configured to support and / or supply and / or process CU and / or DU related functions and / or features, and / or at least one protocol (sub) layer of the RAN (Radio Access Network), such as Layer 2 and / or Layer 3. There may be different functional splits between the central unit and the distributed units. The following will be combined with Figure 4 Examples of such devices and components are described.

[0048] The gNB-CU part and the gNB-DU part can be collocated or physically separated. The gNB-DU can be even further split into two parts, for example, one part includes a processing device and the other part includes an antenna. The central unit (CU) may also be referred to as a baseband unit / radio equipment controller / cloud RAN / virtual RAN (BBU / REC / C-RAN / V-RAN), an open RAN (O-RAN) or a part thereof. The distributed unit (DU) may also be referred to as a remote radio head / remote radio unit / radio equipment / radio unit (RRH / RRU / RE / RU) or a part thereof. Hereinafter, in various example embodiments of the present disclosure, a network node supporting at least one of the central unit functions or layer 3 protocols of a radio access network may be, for example, a gNB-CU. Similarly, a network node supporting at least one of the distributed unit functions or layer 2 protocols of a radio access network may also be, for example, a gNB-DU.

[0049] A gNB-CU may support one or more gNB-DUs. A gNB-DU may support one or more cells and may therefore support a serving cell for a user equipment (UE) or a candidate cell for handover, dual connectivity and / or carrier aggregation.

[0050] User equipment (UE) 150 may be or include a wireless or mobile device, a device having a radio interface for interacting with a RAN (Radio Access Network), a smartphone, an in-vehicle device, an IoT device, or an M2M device, as well as other types of user equipment. Such a UE 150 may include: at least one processor; and at least one memory including program code; wherein the at least one memory and the computer program code are configured to, together with the at least one processor, cause the device to perform at least certain operations, such as, for example, an RRC connection with a RAN. Examples of components of a UE will be combined with Figure 4In an embodiment, the UE 150 may be configured to generate a message (e.g., including a cell ID) to be sent to the RAN via the radio (e.g., to reach and communicate with a serving cell). In an embodiment, the UE 150 may generate and send and receive an RRC message containing one or more RRC PDUs (packet data units). Those skilled in the art will understand the RRC protocol and other processes that the UE may perform.

[0051] Continue to refer Figure 1 In the example of a 5G NR network, the network system 100 provides one or more cells that define a coverage area of ​​the network system 100. As described above, the network system 100 may include a gNB of a 5G NR network, or may include any other device configured to control radio communications and manage radio resources within a cell. As used herein, the term "resource" may refer to radio resources, such as resource blocks (RBs), physical resource blocks (PRBs), radio frames, subframes, time slots, subbands, frequency regions, subcarriers, beams, etc. In an embodiment, the network node 120 may be referred to as a base station.

[0052] Figure 1 An example is provided and is only used to illustrate the network system 100 and the UE 150. Those skilled in the art will appreciate that the network system 100 includes Figure 1 Components not shown in the figure, and it will be understood that other user devices may communicate with the network system 100.

[0053] Figure 2 yes Figure 1 A 5G NR network may be described as an example of a network system 100, and aspects described below should also be applicable to other types of network systems. The network system may be based on Figure 1 The signals and connections shown are operated so that the UE 150 communicates with the network system 100 through the radio access network 225. In addition, as shown and described herein, the network system can be divided into user plane components and functions and control plane components and functions. Unless otherwise specified, the terms "component", "function" and "service" can be used interchangeably herein and can refer to instructions executed by one or more processors and implemented by them.

[0054] The following describes example functionality of these components. The example functionality is illustrative only, and it should be understood that the components described herein may perform additional operations and functionality. In addition, the connections between components may be virtual connections through service-based interfaces, such that any component may communicate with any other component. In this way, any component may act as a service "producer" for any other component that is a service "consumer" to provide services for network functions.

[0055] For example, a core network 210 is described in the control plane of the network system. The core network 210 may include an authentication server function (AUSF) 211, an access and mobility function (AMF) 212, and a session management function (SMF) 213. The core network 210 may also include a network slice selection function (NSSF) 214, a network exposure function (NEF) 215, a network repository function (NRF) 216, and a unified data management function (UDM) 217, which may include a unified data repository (UDR) 224.

[0056] Additional components and functions of the core network 210 may include an application function 218 , a policy control function (PCF) 219 , a network data analysis function (NWDAF) 220 , an analysis data repository function (ADRF) 221 , a management data analysis function (MDAF) 222 , and an operation and management function (OAM) 223 .

[0057] The user plane includes UE 150, radio access network (RAN) 225, user plane function (UPF) 226, and data network (DN) 227. RAN 225 may include a combination of Figure 1 The RAN 225 may include one or more components such as one or more network nodes. However, the RAN 225 may not be limited to such components. The UPF 226 provides a connection for data sent through the RAN 225. For example, the DN 226 identifies services from a service provider, Internet access, and third-party services.

[0058] AMF 212 handles connection and mobility tasks. AUSF 211 receives authentication requests from AMF 212 and interacts with UDM 217 to authenticate and verify network responses to determine successful authentication. SMF 213 performs packet data unit (PDU) session management and manages session contexts with UPF 226.

[0059] NSSF 214 may select a network slice instance (NSI) and determine the allowed network slice selection assistance information (NSSAI). The selection and determination are used to set up AMF 212 to provide services to UE 150. NEF 215 ensures third-party access to network services to create specialized network services. NRF 216 acts as a repository for storing network functions to allow these functions to register and discover each other.

[0060] UDM 217 generates authentication vectors for use by AUSF 211 and ADM 212, and provides user identification processing. UDM 217 can be connected to UDR 224, which stores data associated with authentication, applications, etc. AF 218 provides application services (e.g., streaming services, etc.) to users. PCF 219 provides policy control functions. For example, PCF 219 can assist in network slicing and mobility management, and provide quality of service (QoS) and charging functions.

[0061] NWDAF 220 collects data (e.g., from UE 150 and network systems) to perform network analysis and provide insights into functions that utilize the analysis when providing services. ADRF 221 allows consumers to store, retrieve, and remove data and analysis. MDAF 222 provides additional data analysis services for network functions. OAM 223 provides provisioning and management processing functions to manage elements in or connected to the network (e.g., UE 150, network nodes, etc.).

[0062] Figure 2 are merely examples of components of a network system, and variations are considered to be within the scope of the present disclosure. In an embodiment, a network system may include Figure 2 In an embodiment, the network system may not include other components not shown in the figure. Figure 2 In an embodiment, the components and connections may be used with Figure 2 The connections shown may be implemented in different ways. Such and other embodiments are considered to be within the scope of the present disclosure.

[0063] Although additional details are provided below, as described above, in various embodiments, the UE may be able to operate in N1 mode, where "N1" refers to the interface between the UE and the AMF. Therefore, in order to operate in N1 mode, the UE needs to support the non-access stratum (NAS) protocol (e.g., the 5G mobility management (5GMM) protocol) in the 5G system (5GS). In order to establish communication, the UE attempts to register with a network (e.g., a first network) by sending a registration request using a non-access stratum (NAS) protocol (e.g., the 5GMM protocol). Upon receiving the registration request message from the UE, if no network slice is available, the network may reject the request via a network component (e.g., AMF) and send a registration reject message to the UE (e.g., via a network node). In various embodiments, the registration reject message may include a 5GMM cause value #62 message (e.g., indicating that all single network slice selection assistance information (S-NSSAI) is rejected or unavailable).

[0064] Upon receiving the Registration Reject message, in various embodiments, the UE may disable the N1 mode capability. However, if another radio access technology (RAT) is not provided or a network selection process is initiated, the UE may re-enable the N1 mode capability and continue to issue Registration Request messages to the same network to establish communication. In various embodiments, this may result in a ping-pong effect, where the UE and the network continue to issue unnecessary Registration Request and Registration Reject messages to each other, respectively, resulting in excessive use of network resources.

[0065] That is, if the UE disables the network's N1 mode capability because all S-NSSAIs in the configured NSSAIs are rejected with cause value #62 (e.g., "S-NSSAI is not available in the current public land mobile network (PLMN) or standalone public network (SNPN)" or "S-NSSAI is not available due to network slice specific authentication and authorization failure or revocation"), the UE may re-enable the network's N1 mode capability and the UE may continue to send registration requests to the same network again and again (e.g., via the RAN), as shown in the current procedure in TS24.501.

[0066] Therefore, the UE will continue to receive 5GMM cause value #62 messages again, which refers to the absence of available network slices in either of the above two variant messages, which will continue to trigger the UE to disable N1 mode capability and re-enable N1 mode capability for the network entering a potential loop if the network repeatedly does not provide an appropriate RAT.

[0067] Thus, although additional details are provided below, a method is provided herein in which a UE remembers (e.g., logs) an identifier of a network for which no network slice is available to avoid continuously retransmitting a registration request message before an event (e.g., a first event) occurs.

[0068] As used herein, communication with a radio access network (RAN) may refer to and represent communication with a portion of the RAN, such as with a network node (e.g., DU and / or CU) or another portion of the RAN. As used herein, communication with a core network may refer to and represent communication with one or more services / applications in the core network, such as an AMF or another service of the core network.

[0069] As used herein, in various embodiments, the term "user equipment" or "UE" may be interchangeable with the term "mobile station" or "MS." For example, in various embodiments, the term user equipment or UE may be used to identify a mobile station or MS connected to a network, or the term mobile station or MS may be used to identify a user equipment or UE connected to a network.

[0070] According to the brief description, Figure 3 3 is a diagram of an example embodiment of signals and operations 300 between a UE and an AMF according to one illustrative aspect of the present disclosure. The following paragraphs will describe various signals and operations. It should be understood that the described signals may have associated operations, and the described operations may have associated signals.

[0071] At operation 301, the UE sends a registration request to the AMF, and the AMF receives the registration request. The registration request includes a request for NSSAI (S-NSSAI). In various embodiments, those skilled in the art can understand that, for example, the registration request is sent according to TS24.501.

[0072] Upon receiving the registration request message from the UE, the AMF determines whether a network slice is available and whether the S-NSSAI can be accepted. If the network slice is not available, at operation 302, the AMF sends a registration reject message to the UE, and the UE receives the registration reject message. In various embodiments, the registration reject message may include a 5GMM cause #62 "No network slice available" message. In various embodiments, the registration reject message includes all S-NSSAIs included in the requested NSSAI in the rejected NSSAI of the registration reject message. In various embodiments, the registration reject message may include the cause "S-NSSAI is not available in the current PLMN or SNPN", or the cause "S-NSSAI is not available due to network slice specific authentication and authorization failure or revocation" as the reason for the lack of available network slices. In various embodiments, the cause "S-NSSAI is not available in the current PLMN or SNPN" or the cause "S-NSSAI is not available due to network slice specific authentication and authorization failure or revocation" may be regarded as a semi-permanent cause.

[0073] Therefore, at operation 303, after the UE receives a registration reject message from the AMF and one or more conditions are met (for example, the UE detects that all S-NSSAIs that the UE can request are rejected due to, for example, semi-permanent reasons), the UE disables the N1 mode capability.

[0074] At operation 304, the UE takes action to avoid accessing the same network unless there is a change. In various embodiments, the change may include an event (e.g., a first event) occurring such that the UE begins accessing a network for which the UE receives an indication that no network slices are available.

[0075] In various embodiments, at operation 304, upon receiving a registration reject message from the network (with 5GMM cause #62 “no network slice available”), the UE may maintain a list of PLMNs in which the N1 mode capability is disabled as PLMNs in which the N1 mode is not allowed due to network slice unavailability. In various embodiments, when the UE disables its N1 mode capability upon receiving a registration reject message from the network (with 5GMM cause #62 “no network slice available”), the UE may add the identity or identifier of the PLMN to the list of PLMNs in which the N1 mode is not allowed due to network slice unavailability, and if the timer T NSU If it is not running, a timer (which may be referred to as T NSU ). In various embodiments, the timer T NSU The number of PLMNs that the UE may store where N1 mode is not allowed due to network slice unavailability may be specific to a particular implementation and may include one or more. In addition, in various embodiments, the timer T NSU The value of may be UE implementation specific, but in various implementations, does not exceed the maximum possible value of the background scan timer T (eg, the background scan timer T defined in 3GPP TS 23.122).

[0076] In various embodiments, in automatic PLMN selection, the UE may utilize the stored information by not considering (e.g., discarding / ignoring) PLMNs where N1 mode is not allowed due to network slice unavailability as PLMN selection candidates for NG-RAN access technology (unless no other PLMNs are available). In various embodiments, if the PLMN is available in another RAT, the PLMN may be selected as a PLMN candidate for the NG-RAN access technology.

[0077] In various embodiments, when the UE is switched off, the UE may delete the stored information on the PLMN where N1 mode is not allowed due to network slice unavailability, the Universal Subscriber Identity Module (USIM) is removed from the UE, and the timer T NSU expiration, the UE receives a registration accept message containing a network slice indication information element (IE) including a network slice subscription change indication set to "network slice subscription changed", or the UE removes the S-NSSAI from the rejected NSSAI for a failed or revoked network slice specific authentication and authorization (NSSAA) service.

[0078] In various embodiments, the UE performs network selection only for PLMNs that are not in the list of PLMNs where N1 mode is not allowed due to network slice unavailability.

[0079] In various embodiments, if the UE supports neither access to the SNPN using a certificate from a certificate holder nor access to the SNPN using an equivalent SNPN, the UE may maintain a list of SNPNs in which the N1 mode capability is disabled upon receiving a registration reject message from the network (with 5GMM cause #62 "No network slice available"). In various embodiments, if the UE supports access to the SNPN using a certificate from a certificate holder (which is not a PLMN), an equivalent SNPN, or both, the UE may maintain one or more lists of SNPNs in which the N1 mode capability is disabled upon receiving a registration reject message from the network (with 5GMM cause #62 "No network slice available"), wherein each item in the list is associated with an entry of the "Subscriber Data List".

[0080] In various embodiments, if the UE supports access to the SNPN using a certificate from a certificate holder (which is a PLMN), the UE may maintain a list of SNPNs in which the N1 mode capability is disabled, the list of SNPNs being associated with a PLMN subscription, after receiving a registration reject message from the network (with 5GMM cause #62 "No network slice available"). In various embodiments, if the UE supports access to the SNPN using a certificate from a certificate holder, an equivalent SNPN, or both, the UE may use a list associated with a selected entry of the "Subscriber Data List" or a selected PLMN subscription. When the UE disables its N1 mode capability after receiving a registration reject message from the network (with 5GMM cause #62 "No network slice available"), the UE may perform as follows.

[0081] In various embodiments, the UE may add the identity of the SNPN to the list of SNPNs for which N1 mode is not allowed due to network slice unavailability, and if the timer T NSU_SNPN If it is not running yet, start the timer (which can be called T NSU_SNPN ). In various embodiments, the timer T NSU_SNPN The number of SNPNs that the UE may store for which N1 mode is not allowed due to network slice unavailability may be implementation specific, but in various embodiments is at least one. In various embodiments, the timer T NSU_SNPN The value of may be UE implementation specific.

[0082] In various embodiments, in automatic SNPN selection, the UE may utilize the stored information by not considering (e.g., discarding / ignoring) SNPNs where N1 mode is not allowed due to network slice unavailability as SNPN selection candidates for NG-RAN access technology (unless no other SNPNs are available).

[0083] In various embodiments, when the UE is switched off, the UE may delete the stored information on the SNPN where N1 mode is not allowed due to network slice unavailability, the USIM is removed, the "Subscriber Data List" entry of the SNPN is updated, and the timer T NSU_SNPN Expiration, the UE receives a registration accept message containing a network slice indication IE (the IE includes a network slice subscription change indication set to "network slice subscription has changed"), or the MS removes the S-NSSAI from the rejected NSSAI for a failed or revoked NSSAA service.

[0084] Figure 3 The operations are illustrative only, and variations are considered to be within the scope of the present disclosure. In an embodiment, the operations may include Figure 3 Other operations not shown in the figure. In an embodiment, the operation may not include Figure 3 Each signal and operation shown. In an embodiment, the operation can be performed with Figure 3 The method 300 may be implemented in a different order than the order shown. Such and other embodiments are considered to be within the scope of the present disclosure. It will be appreciated by those skilled in the art that although various example components are described as performing various functions, other components may perform the functions described in method 300. In addition, although the above embodiments are described based on a 5G system (5GS), these embodiments may be applied to systems of different generations.

[0085] Operations are described below from the perspective of a UE. From such a perspective, the method includes sending, by the UE, a first message to a network node, the first message including a request to access a first network according to a NAS protocol. The UE may receive, from the network node, a second message including an indication that no network slice is available to serve access to the first network requested by the UE. The UE may disable the ability to access the network using the NAS protocol based on receiving the second message, store the identity of the first network, and, after storing, utilize the stored identity of the first network by the UE during a network selection process.

[0086] Reference now Figure 4, a block diagram of example components of a UE or network device (e.g., a RAN or core network) is shown. The device includes electronic storage 410, a processor 420, a network interface 440, and a memory 450. The various components can be communicatively coupled to each other. The processor 420 can be and can include any type of processor, such as a single-core central processing unit (CPU), a multi-core CPU, a microprocessor, a digital signal processor (DSP), a system on a chip (SoC), or any other type of processor. The memory 450 can be a volatile type of memory, such as RAM, or a non-volatile type of memory, such as NAND flash memory. The memory 450 includes processor-readable instructions that are executable by the processor 420 to cause the device to perform various operations, including the operations mentioned herein, such as Figure 3 operation.

[0087] Electronic storage 410 may be and include any type of electronic storage for storing data, such as a hard drive, a solid-state drive, an optical disk, and / or other non-transitory computer-readable media, as well as other types of electronic storage. Electronic storage 410 stores processor-readable instructions for causing or configured to cause the device to perform its operations, and also stores data associated with such operations, such as storing data related to the 5G NR standard and other data. Network interface 440 may implement wireless network technologies, such as 5G NR and / or other wireless network technologies.

[0088] Figure 4 The components shown are examples only, and those skilled in the art will understand that the device includes other components not shown, and may include multiples of any of the components shown. Such and other embodiments are considered to be within the scope of the present disclosure.

[0089] Additional embodiments of the present disclosure include the following examples.

[0090] Example 1.1. An apparatus comprising:

[0091] means for sending, by a user equipment (UE) to a network node, a first message comprising a request to access a first network according to a non-access stratum (NAS) protocol;

[0092] means for receiving, by the UE from the network node, a second message comprising an indication that no network slice is available to serve access to the first network requested by the UE;

[0093] means for disabling, by the UE, an ability to access a network using the NAS protocol based on the receiving of the second message;

[0094] means for storing, by the UE, an identity of the first network; and

[0095] means for utilizing, after storing, by the UE during a network selection procedure, the stored identity of the first network.

[0096] Example 1.2. The apparatus of Example 1.1, wherein the first message is a registration request message.

[0097] Example 1.3. An apparatus according to Example 1.2, wherein the registration request message includes a request for one or more single network slice selection assistance information (S-NSSAI).

[0098] Example 1.4. The apparatus of Example 1.3, wherein the second message is a registration reject message.

[0099] Example 1.5. An apparatus according to any one of Examples 1.1 to 1.3, wherein the indication that no network slice is available is a 5G system mobility management (5GMM) cause value #62 "No network slice available" indication.

[0100] Example 1.6. The apparatus of Example 1.1, wherein the disabling the capability to access a network using the NAS protocol comprises disabling N1 mode capability.

[0101] Example 1.7. The apparatus of any of Examples 1.1 to 1.6, further comprising means for discarding, by the UE, the first network during the network selection process.

[0102] Example 1.8. The apparatus of Example 1.1, further comprising means for deleting, by the UE, the stored identity of the first network based on an occurrence of a first event.

[0103] Example 1.9. The apparatus of Example 1.8, wherein the first event comprises expiration of a timer.

[0104] Example 1.10. The apparatus of Example 1.9, wherein the UE starts the timer after disabling the ability to access a network using the NAS protocol.

[0105] Example 1.11. The apparatus of Example 1.8, wherein the first event comprises receiving, by the UE, a third message from the network node.

[0106] Example 1.12. The apparatus of Example 1.11, wherein the third message includes an indication that registration with the first network is available for access by the UE.

[0107] Example 1.13. An apparatus according to Example 1.12, wherein the third message includes an indication that the network slice subscription has been changed.

[0108] Example 1.14. The apparatus of Example 1.8, wherein the first event comprises the UE being turned off.

[0109] Example 1.15. The apparatus of Example 1.8, wherein the first event comprises removal of a universal subscriber identity module from the UE.

[0110] Example 1.16. The apparatus of Example 1.8, wherein the first event comprises a modification to a subscriber data list.

[0111] Example 1.17. The apparatus of Example 1.1, wherein the stored identity is associated with an entry of a subscriber data list.

[0112] Example 1.18. The apparatus of Example 1.1, wherein the network node comprises an access and mobility function (AMF).

[0113] The embodiments and aspects disclosed herein are examples of the present disclosure and may be embodied in various forms. For example, although some embodiments herein are described as separate embodiments, each embodiment herein may be combined with one or more other embodiments herein. The specific structural and functional details disclosed herein should not be interpreted as limitations, but as the basis for the claims, and as a representative basis for teaching those skilled in the art to use the present disclosure in various ways in almost any appropriately detailed structure. Throughout the description of the drawings, the same reference numerals may refer to similar or identical elements.

[0114] According to the present disclosure, the phrases "in one aspect", "in certain aspects", "in various aspects", "in some aspects" or "in other aspects" may each refer to one or more aspects of the same or different aspects. The phrase "plurality" may refer to two or more.

[0115] According to the present disclosure, the phrases "in one embodiment," "in an embodiment," "in various embodiments," "in some embodiments," or "in other embodiments" may each refer to one or more of the same or different embodiments. A phrase of the form "A or B" means "(A), (B), or (A and B)." A phrase of the form "at least one of A, B, or C" means "(A); (B); (C); (A and B); (A and C); (B and C); or (A, B, and C)."

[0116] Any method, program, algorithm or code described herein can be converted into a programming language or computer program, or represented by a programming language or computer program. The terms "programming language" and "computer program" used herein each include any language for specifying computer instructions, and include (but are not limited to) the following languages ​​and their derivatives: assembly language, Basic, batch files, BCPL, C, C++, Delphi, Fortran, Java, JavaScript, machine code, operating system command language, Pascal, Perl, PL1, Python, scripting languages, Visual Basic, the metalanguage of the program itself, and all first generation, second generation, third generation, fourth generation, fifth generation or subsequent computer languages. Also include databases and other data patterns, and any other metalanguage. The language of the interpreted, compiled or compiled and interpreted methods is not distinguished. The compiled version of the program is not distinguished from the source code version. Therefore, if the programming language can exist in more than one state (such as source, compilation, object or link), the reference to the program is a reference to any and all such states. The reference to the program can cover the intention of actual instructions and / or these instructions.

[0117] Although various aspects of the present disclosure have been shown in the accompanying drawings, it is not intended that the present disclosure is limited thereto, as the scope of the present disclosure should be as broad as possible, and the specification should also be read in the same manner. Therefore, the above description should not be interpreted as limiting, but only as an example of specific aspects. Those skilled in the art will be able to envision other modifications within the scope and spirit of the appended claims.

Claims

1. A method for communication, comprising: A first message is sent by a user equipment (UE) to a network node, the first message comprising: a request for accessing a first network according to a non-access stratum (NAS) protocol; receiving, by the UE from the network node, a second message including an indication that no network slice is available to serve access to the first network requested by the UE; disabling, by the UE, a capability of accessing a network using the NAS protocol based on receiving the second message; storing, by the UE, the identity of the first network; and After storing, the stored identity of the first network is utilized by the UE during a network selection procedure. The method according to claim 1 , wherein the first message is a registration request message.

3. The method according to claim 2, wherein the registration request message comprises: A request for one or more Single Network Slice Selection Assistance Information (S-NSSAI). The method according to claim 3 , wherein the second message is a registration rejection message.

5. The method according to any one of claims 1 to 3, wherein the indication that no network slice is available is a 5G system mobility management (5GMM) cause value #62 "no network slice available" indication.

6. The method of claim 1, wherein the disabling the ability to access a network using the NAS protocol comprises: Disable N1 mode capability.

7. The method according to any one of claims 1 to 6, further comprising: During the network selection process, the first network is discarded by the UE.

8. The method according to claim 1, further comprising: The stored identity of the first network is deleted by the UE based on the occurrence of a first event.

9. The method of claim 8, wherein the first event comprises expiration of a timer.

10. The method of claim 9, wherein the UE starts the timer after disabling the ability to access a network using the NAS protocol.

11. The method of claim 8, wherein the first event comprises: A third message is received by the UE from the network node.

12. The method according to claim 11, wherein the third message comprises: Registration with the first network may be used for indication of access by the UE.

13. The method according to claim 12, wherein the third message comprises: An indication that a network slice subscription has been changed.

14. The method of claim 8, wherein the first event comprises: The UE is switched off.

15. The method of claim 8, wherein the first event comprises: A universal subscriber identity module is removed from the UE.

16. The method of claim 8, wherein the first event comprises: Modifications to Subscriber Data Lists.

17. The method of claim 1, wherein the stored identity is associated with an entry of a subscriber data list.

18. The method of claim 1, wherein the network node comprises: Access and Mobility Function (AMF).

19. A user equipment (UE), comprising: at least one processor; as well as At least one memory storing instructions, which, when executed by the at least one processor, cause the user equipment to at least perform the method according to any one of claims 1 to 18.

20. A processor-readable medium storing instructions, which, when executed by at least one processor of a device, cause the device to at least perform the method according to any one of claims 1 to 18.

Images