Network Slice Admission Control (NSAC) Discovery and Roaming Enhancements

Abstract

To provide a network slice admission control function (NSACF) in a 5G core network, an access and mobility management function (AMF) utilizing the NSACF, and a method performed by the AMF.SOLUTION: In a NSACF discovery procedure, an AMF sends a network function registration request to a network resource function (NRF) and receives a response to a network function registration request from an NRF, Next, a network capability discovery request including one or more single network slice selection assistance information (S-NSSAI), and an indication that the discovery request is for a network slice admission control function (NSACF) is transmitted to the NRF and a network capability discovery response containing the NSACF address is received from the NRF.SELECTED DRAWING: Figure 3

Description

PRIORITY INFORMATION / INCORPORATION BY REFERENCE

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 201,705, entitled “Network Slice Admission Control (NSAC) Discovery and Roaming Enhancements,” filed May 10, 2021, which is incorporated by reference in its entirety. [Background technology]

[0002] A network may deploy multiple network slices. In general, a network slice refers to an end-to-end logical network configured to provide a particular service and / or having particular network characteristics. Each of the network slices may be isolated from each other but may operate on a shared network infrastructure. Thus, each of the network slices may share network resources but facilitate different functions.

[0003] A network operator may wish to limit the number of devices registered to a particular network slice. A network may include a Network Slice Admission Control Function (NSACF) to perform this task. For example, the NSACF may perform various operations related to managing the number of UEs and / or sessions registered to an individual network slice. Summary of the Invention

[0004] Some example embodiments relate to an Access and Mobility management Function (AMF) of a 5G core network configured to perform operations including sending a network function registration request to a Network Resource Function (NRF), receiving a response to the network function registration request from the NRF, sending a network function discovery request to the NRF, the network function discovery request including one or more Single Network Slice Selection Assistance Information (S-NSSAI) and an indication that the discovery request is for a Network Slice Admission Control Function (NSACF), and receiving a network capability discovery response from the NRF, the network capability discovery response including an NSACF address.

[0005] Another example embodiment relates to a Network Slice Admission Control Function (NSACF) of a 5G core network configured to perform operations including sending a network function registration request to a Network Resource Function (NRF), receiving a response to the network function registration request from the NRF, sending a network function discovery request to the NRF, the network function discovery request including one or more Single Network Slice Selection Assistance Information (S-NSSAI) and an indication that the discovery request is for an Access and Mobility Management Function (AMF), and receiving a network capability discovery response from the NRF.

[0006] Yet another example embodiment relates to a Network Slice Admission Control Function (NSACF) of a 5G core network configured to perform operations including: maintaining a network slice quota for one or more network slices, where the NSACF is configured to perform Network Slice Admission Control (NSAC) for both a Visiting Public Land Mobile Network (VPLMN) and a Home Public Land Mobile Network (HPLMN), receiving a number of registered User Equipment (UE) per network slice availability check and update requests from an Access and Mobility Management Function (AMF), and sending a response to the AMF, where the response indicates whether a maximum number of registered UEs or sessions for the S-NSSAI has been reached. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 illustrates an exemplary network arrangement in accordance with various exemplary embodiments.

[0008] [Diagram 2] FIG. 1 illustrates an example network architecture in accordance with various exemplary embodiments.

[0009] [Diagram 3] FIG. 1 illustrates a signaling diagram for a Network Slice Admission Control Function (NSACF) discovery procedure, in accordance with various exemplary embodiments.

[0010] [Figure 4]FIG. 1 illustrates a signaling diagram of an Access and Mobility Management Function (AMF) discovery procedure, according to various exemplary embodiments.

[0011] [Diagram 5] 1 illustrates a table showing an example of exemplary information that may be included by a Network Resource Function (NRF) in a discovery response sent to an NSACF during an AMF discovery procedure, according to various exemplary embodiments.

[0012] [Figure 6] 1 illustrates a signaling diagram for an Early Admission Control (EAC) update procedure, in accordance with various exemplary embodiments.

[0013] [Figure 7] 1 illustrates an example of a Local-BreakOut (LBO) roaming scenario in accordance with various exemplary embodiments.

[0014] [Figure 8] 1 illustrates an example of a home routed roaming scenario in accordance with various exemplary embodiments.

[0015] [Figure 9] FIG. 1 illustrates a signaling diagram for several user equipment (UE) per network slice availability check and update procedures in accordance with various exemplary embodiments.

[0016] [Figure 10] 1 illustrates an exemplary UE in accordance with various exemplary embodiments.

[0017] [Figure 11] 1 illustrates an exemplary base station in accordance with various exemplary embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Exemplary embodiments may be further understood with reference to the following description and associated drawings, in which like elements are labeled with the same reference numerals. Exemplary embodiments relate to Network Slice Admission Control (NSAC). As will be appreciated by those skilled in the art, NSAC generally refers to Third Generation Partnership (3GPP) protocols and policies that allow network operators to control the number of devices and / or sessions registered to a particular network slice.

[0019] Exemplary embodiments are described with respect to a fifth generation (5G) network supporting network slicing. In general, network slicing refers to a network architecture in which multiple end-to-end logical networks operate on a shared physical network infrastructure. Each of the network slices may be configured to provide a particular set of capabilities and / or characteristics. Thus, the physical infrastructure of a 5G network may be sliced ​​into multiple virtual networks, each of which is configured for a different purpose. Throughout this description, references to network slices may refer to any type of end-to-end logical network that is configured to serve a particular purpose and is implemented on the 5G physical infrastructure.

[0020] Those skilled in the art will appreciate that 5G may support a variety of different use cases, such as enhanced Mobile BroadBand (eMBB), enhanced Machine Type Communication (eMTC), Industrial Internet of Things (IIoT), and the like. Each type of use case may relate to a variety of different types of applications and / or services. A network slice may be characterized by a type of use case, a type of application and / or service, or an entity that provides an application and / or service via the network slice. However, any examples in this description that characterize a network slice in a specific manner are provided for illustrative purposes only. Throughout this description, references to a network slice may represent any type of end-to-end logical network that is configured to serve a particular purpose and is implemented in a 5G physical infrastructure.

[0021] A network slice may be identified by a Single Network Slice Selection Assistance Information (S-NSSAI). Each instance of the S-NSSAI may be associated with a Public Land Mobile Network (PLMN) and may include a Slice Service Type (SST) and a Slice Descriptor (SD). The SST may identify the expected behavior of the corresponding network slice in terms of services, features, and characteristics. Those skilled in the art will appreciate that the SST may be associated with standardized SST values. The SD may identify any one or more entities associated with the network slice. For example, the SD may indicate an owner or entity (e.g., a carrier) that manages the network slice and / or an entity (e.g., a third party, an entity providing an application / service, etc.) that provides an application / service over the network slice. In some embodiments, the same entity may own the slice and provide the service (e.g., carrier service). Throughout this description, the S-NSSAI refers to a single network slice, and the terms "NSSAI" or "S-NSSAI" may be used interchangeably to refer to one or more network slices.

[0022] A user equipment (UE) may be configured to perform any of a wide variety of different tasks. Thus, a UE may be configured to use one or more network slices. To provide an example, a UE may use a first network slice for one or more carrier services (e.g., voice, Multimedia Messaging Service (MMS), Internet, etc.) and a second, different network slice for third party services. However, the configured purpose of the network slices is beyond the scope of the example embodiments. The example embodiments are not limited to any particular type of network slice. Instead, the example embodiments introduce enhancements related to NSAC.

[0023] Exemplary embodiments are also described with respect to a Network Slice Admission Control Function (NSACF). NSACF refers to a network function configured to control and limit the number of UEs and / or Packet Data Unit (PDU) sessions registered to a particular network slice. To provide an example, an NSACF may perform various operations related to enforcing quotas on the maximum number of UEs registered to a particular network slice (e.g., S-NSSAI). An NSACF service area relates to the location of a network function consumer. However, reference to the term "NSACF" is provided for illustrative purposes only. Different networks may refer to similar concepts by different names, for example, 3GPP networks may use the terms NSACF and Network Slice Quota (NSQ) interchangeably.

[0024] In one aspect, the exemplary embodiments relate to NSAC discovery and Early Admission Control (EAC). As described in more detail below, the exemplary embodiments include enhancements to an Access and Mobility Management Function (AMF) initiated NSACF discovery procedure, an NSACF initiated AMF discovery procedure, and an EAC update procedure between the AMF and NSACF. In another aspect, the exemplary embodiments relate to NSAC within the context of a roaming scenario. As described in more detail below, the exemplary embodiments include enhancements to an NSACF deployed by a Visited Public Land Mobile Network (VPLMN) and an NSACF deployed by a Home Public Land Mobile Network (HPLMN). The exemplary enhancements described herein may be used with currently implemented NSAC protocols and policies, or future implementations of NSAC protocols and policies.

[0025] 1 illustrates an exemplary network deployment 100 in accordance with various exemplary embodiments. The exemplary network deployment 100 includes a UE 110. Those skilled in the art will appreciate that the UE 110 may be any type of electronic component configured to communicate over a network, such as a mobile phone, a tablet computer, a desktop computer, a smartphone, a phablet, an embedded device, a wearable device, an Internet of Things (IoT) device, etc. It should also be appreciated that an actual network deployment may include any number of UEs being used by any number of users. Thus, the example of a single UE 110 is provided for illustrative purposes only.

[0026] The UE 110 may be configured to communicate with one or more networks. In the example of the network deployment 100, the network with which the UE 110 may communicate wirelessly is a 5G New Radio (NR) Radio Access Network (RAN) 120. However, the UE 110 may also communicate with other types of networks (e.g., 5G Cloud RAN, Next Generation RAN (NG-RAN), Long Term Evolution (LTE) RAN, legacy cellular networks, Wireless Local Area Network (WLAN), etc.), and the UE 110 may also communicate with a network by a wired connection. Thus, in this example, the UE 110 may have a 5G NR chipset to communicate with the 5G NR RAN 120.

[0027] The 5G NR RAN 120 may be part of a cellular network that may be deployed by a cellular provider (e.g., Verizon, AT&T, T-Mobile, etc.). The 5G NR RAN 120 may include, for example, cells or base stations (NodeB, eNodeB, HeNB, eNBS, gNB, gNodeB, macro cell, micro cell, small cell, femto cell, etc.) configured to transmit and receive traffic from UEs equipped with appropriate cellular chipsets. In the network deployment 100, the 5G NR RAN 120 is shown as gNB 120A. However, an actual network deployment may include any number of different types of base stations or cells deployed by any number of RANs. Thus, the example of a single 5G NR RAN 120 and a single gNB 120A is provided for illustrative purposes only.

[0028] Those skilled in the art will appreciate that any association procedure may be performed for the UE 110 to connect to the 5G NR RAN 120. For example, as described above, the 5G NR RAN 120 may be associated with a particular network carrier for which the UE 110 and / or a user of the UE 110 has a subscription and credential information (e.g., stored in a SIM card). Upon detecting the presence of the 5G NR RAN 120, the UE 110 may transmit the corresponding credential information to associate with the 5G NR RAN 120. More specifically, the UE 110 may associate with a particular base station or cell (e.g., gNB 120A).

[0029] The network deployment 100 also includes a cellular core network 130, an Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network services backbone 160. The cellular core network 130 may be considered to be an interconnected set of components that manage the operation and traffic of a cellular network. It may include an Evolved Packet Core (EPC) and / or a 5G Core (5GC). The cellular core network 130 also manages traffic flowing between the cellular network and the Internet 140. The IMS 150 may generally be described as an architecture for delivering multimedia services to the UE 110 using IP protocols. The IMS 150 may communicate with the cellular core network 130 and the Internet 140 to provide the multimedia services to the UE 110. The network services backbone 160 communicates directly or indirectly with the Internet 140 and the cellular core network 130. The network services backbone 160 may generally be described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a suite of services that may be used to extend the capabilities of the UE 110 to communicate with various networks.

[0030] 2 illustrates an example network architecture 200 in accordance with various example embodiments. The following description provides a general overview of the various components of the example architecture 200. The specific operations performed by the components for example embodiments are described in more detail following the description of the architecture 200.

[0031] Those skilled in the art will appreciate that the components of the example architecture 200 may reside in various physical and / or virtual locations relative to the network deployment 100 of Figure 1. These locations may include within an access network (e.g., RAN 120), within a core network 130, as separate components outside of the locations discussed with respect to Figure 1, etc.

[0032] In FIG. 2, the various components are shown as being connected via connections labeled Nx (e.g., N1, N2, N11, Nsmf, Namf, Nnssf, Nnrf, Nnsacf, etc.). One skilled in the art will appreciate that each of these connections (or interfaces) is defined in the 3GPP specifications. The example architecture 200 uses these connections in the manner in which they are defined in the 3GPP specifications. Additionally, although these interfaces are referred to as connections throughout this description, it should be understood that these interfaces need not be direct wired or wireless connections, e.g., the interfaces may communicate through intervening hardware and / or software components. To provide an example, the UE 110 may exchange signals over the air with the cell 120A. However, in the architecture 200, the UE 110 is shown as having a connection to the AMF 205. This connection or interface is not a direct communication link between the UE 110 and the AMF 205, but is a connection facilitated by intervening hardware and software components. Thus, throughout this description, the terms "connection" and "interface" may be used interchangeably to describe the Nx interfaces between the various components.

[0033] The architecture 200 includes a UE 110 and a 5G NR RAN 120. The UE 110 and the 5G NR RAN 120 are connected to an AMF 205. The AMF 205 is generally responsible for connectivity and mobility management in the 5G NR RAN 120. For example, the AMF 205 may perform operations related to managing registration procedures between the UE 110 and the core network 130. The example embodiment is not limited to the AMF performing the above referenced operations. Those skilled in the art will appreciate the various different types of operations that the AMF may perform. Furthermore, reference to a single AMF 205 is merely for illustrative purposes and an actual network deployment may include any suitable number of AMFs.

[0034] The AMF 205 is connected to a Session Management Function (SMF) 210. The SMF 210 may perform operations related to session management, including, but not limited to, session establishment, session release, IP address allocation, policy and Quality of Service (QoS) enforcement, etc. The exemplary embodiment is not limited to the SMF performing the above referenced operations. Those skilled in the art will appreciate the various different types of operations that an SMF may perform. Furthermore, reference to a single SMF 210 is for illustrative purposes only and an actual network deployment may include any suitable number of SMFs.

[0035] The AMF 205 and the SMF 210 are also connected to a Network Slice Selection Function (NSSF) 215, a Network Resource Function (NRF) 220, and an NSACF 225. The NSSF 215 performs operations related to network slicing. For example, the NSSF 215 may select a set of network slice instances to serve the UE 110. The NSSF 215 may also manage one or more databases including a mapping table of S-NSSAIs and frequency bands in which the S-NSSAIs are authorized to operate. The NRF 220 may perform operations related to a network service discovery function that allows network functions to determine where and how to access other network functions. However, reference to the term network resource function is provided for illustrative purposes only. Different networks may refer to similar entities by different names, for example, 3GPP networks may use the terms network resource function and network repository function interchangeably.

[0036] The NSACF 225 may be configured to perform operations related to controlling the number of registered UEs and / or sessions per network slice for network slices that are subject to NSAC. During operation, the NSACF 225 may check a count of UEs and / or PDU sessions registered to the S-NSSAI and may determine whether a network slice quota has been reached. The NSACF 225 may then accept or reject a register request based on the count and quota. However, the reference to a quota concept is provided for illustrative purposes only. Those skilled in the art will appreciate that different entities may refer to similar concepts by different names. For example, a 3GPP network may use the terms quota and admission control to refer to the same concept. Furthermore, the reference to a single NSACF 225 is for illustrative purposes only and an actual network deployment may include any suitable number of NSACFs.

[0037] To provide a more concrete example, the NSACF 225 may be configured with a maximum number of PDU sessions per network slice that are allowed to be served by multiple network slices that are subject to the NSAC. During operation, the SMF 210 may be triggered to send a request to the NSACF 225 for a maximum number of PDU sessions per network slice admission control during a PDU session establishment / release procedure. The NSACF 225 may control (e.g., increase, decrease, etc.) the current number of PDU sessions per network slice such that the current number of PDU sessions per network slice does not exceed the maximum number of PDU sessions allowed to be served by the network slice. When the current number of PDU sessions in a network slice is increased, the NSACF 225 may check whether the maximum number of PDU sessions per network slice for the network slice has already been reached. The NSACF 225 may then accept or reject the request based on the count and the quota.

[0038] To provide another example, the NSACF 225 may be configured with a maximum number of UEs per network slice that are allowed to be served by each of the network slices that are subject to the NSAC. During operation, the AMF 205 may be triggered to send a request to the NSACF 225 for a maximum number of UEs per network slice admission control when a registration status of a UE for a network slice that is subject to the NSAC may change. The registration status may change during procedures including, but not limited to, a UE registration procedure, a UE deregistration procedure, a network slice specific authentication and authorization procedure, a network slice specific re-authorization and re-authorization procedure triggered by an Authentication Authorization and Accounting (AAA) server, and a slice specific re-authorization triggered by an AAA server. As described above, the NSACF 225 may control (e.g., increase, decrease, etc.) the current number of UEs registered in a network slice such that the current number of UEs registered in the network slice does not exceed the maximum number of UEs allowed to register in the slice. The NSACF 225 may also maintain a list of UE IDs registered in the network slices that are subject to the NSAC. When the current number of UEs registered in a network slice is to be incremented, NSACF 225 may first check whether the UE identity is already in the list of UEs registered in that network slice. If not, NSACF 225 may check whether the maximum number of UEs per network slice for that particular network slice has already been reached. NSACF 225 may then accept or reject the request based on the count and the quota.

[0039] Various example enhancements related to NSAC discovery are described in detail below. First, enhancements to the NSACF discovery procedure initiated by the AMF 205 are described with respect to the signaling diagram 300 of Figure 3. Then, an example AMF discovery procedure initiated by the NSACF 225 is described with respect to the signaling diagram 400 of Figure 4. Then, an example EAC update procedure between the AMF 205 and the NSACF 225 is described with respect to the signaling diagram 600 of Figure 6. The example AMF discovery procedure may provide a basis for the enhancements introduced for the example EAC update procedure.

[0040] 3 illustrates a signaling diagram 300 for an NSACF discovery procedure in accordance with various exemplary embodiments. The signaling diagram 300 is described with respect to the network architecture 200, which includes the AMF 205 and the NRF 220.

[0041] The NSACF discovery procedure may be initiated by the AMF 205. At 305, the AMF 205 may send a network capability registration request to the NRF 220. For example, the network capability registration request may be sent by the AMF 205 to the NRF 220 via the Namf and / or Nnrf interfaces shown in FIG. 2. This request may be referred to as "Nnrf_NFManagement_NFRegister_Request" and may include one or more Globally Unique AMF IDs (GUAMIs) and a list of S-NSSAI(s) supported by the AMF 205. Thus, when the consumer of the Nnrf_NFManagement_NFRegister service is the AMF 205, the AMF 205 may include a list of S-NSSAI(s) that the AMF 205 supports in the Nnrf_NFManagement_NFRegister operation.

[0042] Under existing circumstances, a list of S-NSSAI(s) supported by the AMF 205 is not provided to the NRF 220. As described in more detail below with respect to Figure 4, this example enhancement enables the NRF 220 to know the S-NSSAI(s) supported by this particular AMF 205. Thus, the NRF 220 can provide the list of AMF 205 supported S-NSSAI(s) to the NSACF 225 in the AMF discovery procedure.

[0043] At 310, the NRF 220 may send a response to the network function registration request to the AMF 205. The response may indicate whether the registration request was successful or not. For example, the response may be sent by the NRF 220 to the AMF 205 via the Nnrf and / or Namf interfaces shown in FIG. 2. The request may be referred to as "Nnrf_NFManagement_NFRegister_Response" and may include a result (e.g., success, failure, etc.). In this example, it is assumed that the registration attempt was successful.

[0044] At 315, the AMF 205 may send a discovery request to the NRF 220. For example, the discovery request may be sent by the AMF 205 to the NRF 220 via the Nnrf and / or Namf interfaces shown in FIG. 2. This request may be referred to as "Nnrf_NFDiscovery_Request" and may include the S-NSSAI(s) and an indication that the discovery request is for an NSACF. Thus, if the target network function of the Nnrf_NFDiscovery service is an NSACF, the discovery request may include the S-NSSAI(s).

[0045] At 320, the NRF 220 may send a discovery response to the AMF 205. For example, the discovery response may be sent by the NRF 220 to the AMF 205 via the Nnrf and / or Namf interfaces shown in FIG. 2. This response may be referred to as "Nnrf_NFDiscovery_Response" and may include an address for the NSACF 225. In addition, this response may include other S-NSSAI(s) supported by the NSACF 225. Thus, if the target network function of the Nnrf_NFDiscovery service is the NSACF 225, the discovery response may include a list of S-NSSAI(s) for which the NSACF 225 manages admission control.

[0046] Under existing circumstances, other S-NSSAI(s) supported by NSACF 225 are not provided to AMF 205 during the discovery procedure. Therefore, when a particular S-NSSAI is provided to NRF 220 in a discovery request and the corresponding NSACF address is provided in the response, AMF 205 may only recognize the NSACF that corresponds to that particular S-NSSAI.

[0047] The example embodiment incorporates the other S-NSSAI(s) supported by the NSACF 225 in the discovery response in an attempt to reduce the number of subsequent discovery requests that may be sent by the AMF 205. For example, the AMF 205 may use the information of the other S-NSSAI(s) supported by the NSACF 225 received at 320 to determine that the requested NSSAI in the registration request from the UE 110 includes an S-NSSAI that is subject to access control for which the AMF 205 has not previously performed an NSACF discovery procedure. In other words, since the AMF 205 knows the other S-NSSAI(s) supported by the NSACF 225, the AMF 205 may use the information received at 320 instead of sending a subsequent discovery request to the NRF 220. This allows the AMF 205 to proceed to the next step of the registration process (e.g., requesting the NSACF 225 to check if quota is available for another UE / session, sending a context request to the SMF 210, or any other appropriate action) without sending a discovery request to the NRF 220.

[0048] 4 illustrates a signaling diagram 400 for an AMF discovery procedure in accordance with various example embodiments. The signaling diagram 400 is described with respect to the network architecture 200, which includes the NSACF 225 and the NRF 220.

[0049] The AMF discovery procedure may be initiated by NSACF 225. At 405, NSACF 225 may send a network capability registration request to NRF 220. For example, the network capability registration request may be sent by NSACF 225 to NRF 220 via the Nnsacf and / or Nnrf interfaces shown in FIG. 2. This request may be referred to as "Nnrf_NFManagement_NFRegister_Request" and may include a list of S-NSSAI(s) supported by NSACF 225. Thus, when the consumer of the Nnrf_NFManagement_NFRegister service is NSACF 335, NSACF 225 may include a list of S-NSSAI(s) for which NSACF 225 manages access control in the Nnrf_NFManagement_NFRegister operation.

[0050] Under existing circumstances, a list of S-NSSAI(s) supported by the NSACF 225 is not provided to the NRF 220. This example enhancement enables the NRF 220 to know the S-NSSAI(s) supported by this particular NSACF 225. Thus, as shown in signaling diagram 300, the NRF 220 can provide the list of NSACF 225 supported S-NSSAI(s) to the AMF 205 in the NSACF discovery procedure. Thus, in some embodiments, the above example enhancement with respect to 320 in signaling diagram 300 can be enabled by this message at 405.

[0051] At 410, the NRF 220 may send a response to the network function registration request to the NSACF 225. The response may indicate whether the registration request was successful or not. For example, the response may be sent by the NRF 220 to the NSACF 225 via the Nnrf and / or Nnsacf interfaces shown in FIG. 2. The request may be referred to as "Nnrf_NFManagement_NFRegister_Response" and may include a result (e.g., success, failure, etc.). In this example, it is assumed that the registration attempt was successful.

[0052] At 415, the NSACF 225 may send a discovery request to the NRF 220. For example, the discovery request may be sent by the NSACF 225 to the NRF 220 via the Nnrf and / or Nnsacf interfaces shown in FIG. 2. This request may be referred to as "Nnrf_NFDiscovery_Request" and may include the S-NSSAI(s) and an indication that the discovery request is for the AMF 205.

[0053] At 420, the NRF 220 may send a discovery response to the NSACF 225. For example, the discovery response may be sent by the NRF 220 to the NSACF 225 via the Nnrf and / or Nnsacf interfaces shown in FIG. 2. This response may be referred to as "Nnrf_NFDiscovery_Response" and may include a list of one or more AMFs, their corresponding GUAMI(s), and S-NSSAI(s) supported by each of the AMFs. Thus, if the target network function of the Nnrf_NFDiscovery service is the AMF 205, the discovery response may include a list of GUAMI(s), a list of GUAMI(s) for which it can be a server as a backup, and the S-NSSAI(s) that the AMF 205 supports.

[0054] It should be understood that the methods 300, 400 of Figures 3 and 4, respectively, may be related to one another and that the various operations of these methods may be performed in any order. For example, in some exemplary embodiments, the NSACF registration operations 405 and 410 of method 400 may be performed. After the NSACF registration is completed, method 300 may be performed by the AMF. Thus, in this example, the NSACF registration operation precedes the AMF operation of Figure 3. In other exemplary embodiments, other orders of the operations of methods 300 and 400 may be used.

[0055] 5 shows a table 500 illustrating an example of exemplary information that may be included by the NRF in a discovery response sent to the NSACF during an AMF discovery procedure. In this example, the table includes a column 505 for AMF details, a column 510 for the corresponding GUAMI, and a column 515 for a list of S-NSSAI(s) supported by the corresponding GUAMI. This column may be used as a lookup table by NSACF 225 to find an appropriate AMF for the EAC update procedure.

[0056] Under existing circumstances, a list of one or more AMFs, their corresponding GUAMI(s), and S-NSSAI(s) supported by each of the AMFs is not provided to NSACF 225. In some embodiments, this exemplary enhancement may be enabled by the exemplary enhancement introduced at 305 of signaling diagram 300, which includes AMF 205 providing a list of GUAMI(s) and S-NSSAI(s) supported by AMF 205 during the NSACF discovery procedure.

[0057] Signaling diagram 400 introduces the NSACF as a consumer for several NRF services and operations. Specifically, NSACF 225 is shown as being a consumer of Nnrf_NFmanagement services, such as NFRegister request and response operations. In addition, NSACF 225 is shown as being a consumer of Nnrf_NFDiscovery services, such as NFDiscovery request and response operations. Thus, although not shown in signaling diagram 400, NSACF 225 may also be a consumer of the Nnrf_NFmanagement service "NFupdate" request / response operations, and "NFDeregister" request / response operations.

[0058] In addition, the example enhancement shown at 420 may provide a basis for an example enhancement introduced for the EAC update procedure. The EAC update procedure indicates to the AMF 204 the activation or deactivation of the EAC mode for the S-NSSAI that is subject to NSAC. It will be understood by those skilled in the art that the EAC mode of the S-NSSAI may control whether the AMF 205 needs to perform a network slice availability check and update procedure before the S-NSSAI is considered an authorized S-NSSAI of the UE 110.

[0059] 6 illustrates a signaling diagram 600 for an example EAC update procedure in accordance with various exemplary embodiments. The signaling diagram 600 is described with respect to the network architecture 200, which includes the NSACF 225 and the AMF 205.

[0060] At 605, the NSACF 225 determines that a number of UEs (or sessions) registered in the network slice subject to NSAC exceeds a threshold, which suggests whether the EAC mode for the S-NSSAI should be activated or deactivated.

[0061] At 610, the NSACF 225 sends an EAC mode activation or deactivation command to the AMF 205. For example, the determination at 605 may trigger the NSACF 225 to send a message including one or more S-NSSAIs and an EAC flag for each of the S-NSSAIs. The EAC flag for the S-NSSAI may be set to be activated if the number of UEs registered in the network slice exceeds a threshold. Alternatively, the EAC flag for the S-NSSAI may be set to be deactivated if the number of UEs registered in the network slice falls below a threshold. This message may be referred to as an "Nnsacf_NumberOfUEsPerSliceEACnotify" message.

[0062] It has been identified that under existing circumstances, the NSACF 225 may not be able to determine which of the AMFs deployed by the network should be notified when a threshold is reached. The above example enhancements to the signaling diagrams 300-400 may provide a solution to this problem. For example, one of the example enhancements introduced in the signaling diagram 300 was the AMF 205 providing the NRF 220 with the GUAMI(s) and a list of S-NSSAI(s) supported by the AMF 205 in the registration request 405. According to another example enhancement introduced in the signaling diagram 400, the information obtained by the NRF 220 (e.g., the list of S-NSSAI(s) supported by the AMF 205) may be provided to the NSACF 225 in the AMF discovery response. Now that the NSACF 225 has this information, the NSACF may trigger a Nnsacf_NumberOfUEsPerSliceEACnotify operation to notify only the AMFS or AMFSs that support the corresponding S-NSSAI.

[0063] At 615, the AMF 205 uses the EAC flag to determine when to trigger a network slice availability check and a number of UEs per update procedure, which can reduce delays for the registration procedure and can avoid adversely affecting already authorized network slices.

[0064] When the EAC flag suggests that the EAC mode should be activated, the AMF 205 may trigger a network slice availability check and a number of UE per update procedures before the registration accept step of the registration procedure or before the UE configuration update message. In other words, if the quota for the network slice may have been reached, the AMF 205 may perform an availability check before these messages are provided to the UE 110. When the EAC flag suggests that the EAC mode should be deactivated, the AMF 205 triggers a network slice availability check and a number of UE per update procedures after the registration accept step of the registration procedure or after the UE configuration update message.

[0065] In another aspect, the exemplary embodiments relate to the behavior of the NSACF within the context of a roaming scenario.Before describing the exemplary embodiments, an example of two different roaming scenarios is described below.

[0066] 7 illustrates an example of a local breakout (LBO) roaming scenario 700. The example 700 includes a UE 110, a VPLMN 710, an HPLMN 750, a data network 715, an NSACF deployed by a VPLMN (vNSACF) 712, an NSACF deployed by an HPLM (hNSACF) 852, a Security Edge Protection Proxy (SEPP) 714 on the VPLMN side, and a SEPP 754 on the HPLMN side. Those skilled in the art will appreciate that the SEPPs 714, 754 may act as a service relay between the VPLMN 710 and the HPLMN 750 to provide secure connectivity and hide the network topology.

[0067] In LBO, data traffic may be routed directly from the VPLMN 710 to the data network 715, while authentication and processing of subscription data is handled in the HPLMN 750. Here, an Internet Protocol (IP) address of the data network 715 may be obtained from the VPLMN 715 by the UE 110.

[0068] 8 illustrates an example of a home routed roaming scenario 800. The example 800 includes a UE 110, a VPLMN 810, an HPLMN 850, a data network 855, an NSACF deployed by the VPLMN (vNSACF) 812, an NSACF deployed by the HPLMN (hNSACF) 852, a SEPP 814 on the VPLMN side and a SEPP 854 on the HPLMN side. Those skilled in the art will appreciate that the SEPPs 814, 854 may act as a service relay between the VPLMN 810 and the HPLMN 850 to provide secure connectivity and to hide the network topology.

[0069] In a home routed scenario, VPLMN 810 data traffic is routed through the HPLMN 850 to the data network 855. This scenario gives the operator more control over providing roaming services, policies and charging to the recipient, where the IP address for the data network 855 can be obtained from the HPLMN 850.

[0070] In a roaming scenario, depending on the operator's policy, roaming agreement or Service Level Agreement (SLA) between the VPLMN and the HPLMN, NSAC for a roaming UE may be performed by both the VPLMN and the HPLMN. For example, the NSACF in the VPLMN may be configured by both the HPLMN and the VPLMN with the maximum number of roaming UEs per network slice that are allowed to be served by each of the network slices that are subject to NSAC. The NSACF in the VPLMN may perform NSAC for both the S-NSSAI in the VPLMN and the corresponding mapped S-NSAAI in the HPLMN.

[0071] To provide an example, within the context of the LBO roaming scenario 700, for an NSAC of a roaming UE (e.g., UE 110) managed by the VPLMN 710, the NSACF (e.g., vNSACF 712) may be configured with a maximum number of PDU sessions per network slice in LBO mode that are allowed to be served by each of the network slices that are subject to the NSAC.

[0072] In the LBO roaming scenario 700, for a maximum number of UEs per network slice admission control, the AMF may trigger a request to an NSACF in the serving PLMN (e.g., vNSACF 712) to perform network slice admission control. In this example, an NSACF in the HPLMN (e.g., hNSACF 752) may not be included.

[0073] To provide an example, within the context of a home routed roaming scenario 800, an NSACF (e.g., hNSACF 852) in the HPLMN 850 may be configured with a maximum number of PDU sessions per network slice, and an NSACF (e.g., vNSACF 812) in the VPLMN 810 may be configured with a maximum number of PDU sessions per network slice in home routed mode that are allowed to be served by each of the network slices that are subject to NSAC. Both NSACFs (e.g., hNSACF 852, vNSACF 812) may perform NSAC, with the vNSACF 812 performing NSAC for an S-NSSAI in the VPLMN 810 and the hNSACF 852 in the HPLMN 850 performing NSAC for a corresponding mapped S-NSSAI in the HPLMN.

[0074] In the home routed roaming scenario 800, the SMF of the VPLMN may trigger a request to the vNSACF 812 in the VPLMN 810 for a maximum number of PDU sessions per network slice admission control. In addition, the SMF of the HPLMN 850 may trigger a request to the hNSACF 852 in the HPLMN 850 to perform a maximum number of PDU sessions admission control.

[0075] 9 illustrates a signaling diagram 900 for several UEs per network slice availability check and update procedure according to various example embodiments. First, a general overview of the signaling diagram 900 is provided with respect to the network architecture of FIG. 2. Thus, the signaling diagram 900 includes the AMF 205 and the NSACF 225. Then, enhancements to the network slice admission control support for roaming are described with respect to the signaling diagram 900, the LBO roaming scenario 700, and the home routed roaming scenario 800.

[0076] The network slice availability check and number of UEs per update procedure is to update (e.g., increase or decrease) the number of UEs registered in the S-NSSAI that are subject to NSAC. The AMF 205 may be configured with information that indicates which network slices are subject to NSAC.

[0077] At 905, the AMF 205 triggers a network slice availability check and number of UEs per update procedure to update the number of UEs registered in the network slice when a network slice that is the subject of the NSAC is included in or removed from the allowed NSSAI for the UE.

[0078] At 910, the AMF 205 sends a number of UEs per Slice availability check and update request to the NSACF 225. For example, this message may be referred to as "Nnsacf_NumberOfUEsPerSliceAvailailityCheckandUpdate_Request" and includes information including, but not limited to, the UE IDs, the S-NSSAI(s) for which the number of registered UEs per network slice update is required, and an update flag indicating whether the number of registered UEs per network slice update should be increased or decreased.

[0079] At 915, the NSACF 225 updates the current number of registered UEs for the S-NSSAI. For example, the NSCAF 225 may increase or decrease the number of registered UEs per network slice based on the information provided by the AMF 205 in the update flag parameter.

[0080] At 920, the NSACF 225 sends a response to the request to the AMF 205. For example, this message may be referred to as "Nnsacf_NumberOfUEsPerSliceAvailabilityCheckandUpdate_Response" and includes information including, but not limited to, the S-NSSAI(s) for which the maximum number of UEs per network slice has already been reached, along with a result parameter indicating that the maximum number of UEs registered to the network slice has been reached. If all of the S-NSSAIs that the NSACF 225 returned to the AMF 205 have been reached, the AMF 205 may reject the request from the UE 110. Otherwise, the AMF 205 returns a registration accept message, in which the AMF 205 includes the rejected S-NSSAI(s) in a rejected NSSAI list.

[0081] For NSAC of roaming UE, the maximum number of roaming UEs per network slice, or the maximum number of PDU sessions per network slice in LBO mode, or the maximum number of PDU sessions per network slice in home routed mode, is assigned to the VPLMN per SLA agreement and stored in one responsible vNSACF for S-NSSAI. The maximum number of registered UEs in network slice monitoring and enforcement is performed by the vNSACF in the VPLMN. However, in 910 of the signaling diagram 900, in the "Nnsacf_NumberOfUEsPerSliceAvailabilityCheckandUpdate_Request" service operation, the AMF 205 may provide both the S-NSSAI in the VPLMN and the corresponding mapped S-NSSAI in the HPLMN to the vNSACF. At 915, the vNSACF performs NSAC for the S-NSSAI in the VPLMN based on the UE's SLA with the HPLMN.

[0082] In the home routed roaming scenario 800, the maximum number of PDU sessions per network slice monitoring and enforcement is performed in both the VPLMN 810 by the vNSACF 812 and the HPLMN 850 by the hNSACF 852.

[0083] Figure 10 illustrates an exemplary UE 110 in accordance with various exemplary embodiments. The UE 110 will be described with respect to the network arrangement 100 of Figure 1. The UE 110 may include a processor 1005, a memory arrangement 1010, a display device 1015, Input / Output (I / O) devices 1020, a transceiver 1025, and other components 130. The other components 1030 may include, for example, audio input devices, audio output devices, a power source, a data acquisition device, ports for electrically connecting the UE 110 to other electronic devices, etc.

[0084] The processor 1005 may be configured to execute multiple engines of the UE 110. For example, the engines may include a session management engine 1035. The session management engine 1035 may perform various operations related to establishing and maintaining PDU sessions.

[0085] The engine 1035 described above as an application (e.g., a program) executed by the processor 205 is provided for illustrative purposes only. The functionality associated with the engine 235 may also be represented as a separate, integrated component of the UE 110, or may be a modular component coupled to the UE 110, such as an integrated circuit with or without firmware. For example, the integrated circuit may include input circuitry for receiving signals and processing circuitry for processing signals and other information. The engine may also be embodied as an application or separate applications. Additionally, in some UEs, the functionality described for the processor 1005 is split between two or more processors, such as a baseband processor and an application processor. The exemplary embodiments may be implemented in any of these or other configurations of a UE.

[0086] The memory device 1010 may be a hardware component configured to store data related to operations performed by the UE 110. The display device 1015 may be a hardware component configured to show data to a user, and the I / O device 1020 may be a hardware component that allows a user to provide input. The display device 1015 and the I / O device 1020 may be separate components or may be integrated together, such as a touch screen. The transceiver 1025 may be a hardware component configured to establish a connection with the 5G NR-RAN 120 and / or any other suitable type of network. Thus, the transceiver 1025 may operate at a variety of different frequencies or channels (e.g., a set of contiguous frequencies).

[0087] 11 illustrates an exemplary base station 1100 in accordance with various exemplary embodiments. The base station 1100 may represent any access node (e.g., gNB 120Ae, etc.) through which a UE 110 can establish a connection and manage network operations.

[0088] The base station 1100 may include a processor 1105, a memory unit 1110, input / output (I / O) devices 1115, a transceiver 1120, and other components 1125. The other components 1125 may include, for example, a battery, a data acquisition device, a port for electrically connecting the base station 1100 to other electronic devices, etc.

[0089] The processor 1105 may be configured to execute multiple engines of the base station 1100. However, reference to the processor 1105 is merely exemplary. The functionality associated with the engines may also be represented as separate integrated components of the base station 1100, or may be modular components coupled to the base station 1100, such as integrated circuits with or without firmware. For example, the integrated circuits may include input circuitry for receiving signals and processing circuitry for processing signals and other information. Additionally, in some base stations, the functionality described for the processor 305 is divided among multiple processors (e.g., baseband processors, application processors, etc.). The exemplary embodiments may be implemented in any of these or other configurations of a base station.

[0090] The memory 1110 may be a hardware component configured to store data related to operations performed by the base station 1100. The I / O device 1115 may be a hardware component or port that allows a user to interact with the base station 1100. The transceiver 1120 may be a hardware component configured to exchange data with the UE 110 and any other UEs in the system 100. The transceiver 1120 may operate at a variety of different frequencies or channels (e.g., a set of contiguous frequencies). Thus, the transceiver 1120 may include one or more components (e.g., radios) to enable data exchange with various networks and UEs.

[0091] example In a first example, a network slice admission control function (NSACF) of a 5G core network is configured to perform operations including: maintaining a network slice quota for one or more network slices, where the network function is a network slice admission control function (NSACF) configured to perform network slice admission control (NSAC) for both a visited public land mobile network (VPLMN) and a home public land mobile network (HPLMN); receiving a number of registered user equipment (UE) per network slice availability check and update requests from an access and mobility management function (AMF); and sending a response to the AMF, where the response indicates whether a maximum number of registered UEs or sessions for the S-NSSAI has been reached.

[0092] In a second example, the NSACF of the first example, the operations further include receiving a maximum number of roaming UEs per network slice for a single network slice selection assistance information (S-NSSAI) in a visited public land mobile network (VPLMN) and receiving a maximum number of roaming UEs per network slice for a corresponding mapped S-NSAAI in a home public land mobile network (HPLMN).

[0093] In a third example, the NSACF of the first example, wherein the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN) configured with a maximum number of packet data unit (PDU) sessions per network slice in local breakout mode (LBO).

[0094] In a fourth example, the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN) configured with a maximum number of packet data unit (PDU) sessions per network slice in home routed mode, the NSACF of the first example.

[0095] In a fifth example, the NSACF of the fourth example, wherein the NSACF deployed by the VPLMN is configured to perform network slice admission control (NSAC) for a single network slice selection assistance information (S-NSSAI), and the NSACF deployed by the home public land mobile network (HPLMN) is configured to perform NSAC for a corresponding mapped S-NSSAI.

[0096] In a sixth example, the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN), and the request is received from a session management function (SMF) deployed by the VPLMN, the NSACF of the first example.

[0097] In a seventh example, the NSACF of the first example, wherein the quota includes a maximum number of packet data unit (PDU) sessions per network slice in local breakout (LBO) mode.

[0098] In an eighth example, the NSACF of the first example, wherein the quota includes a maximum number of packet data unit (PDU) sessions per network slice in a home routed mode.

[0099] In a ninth example, the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN), the NSACF of the first example.

[0100] In a tenth example, the NSACF of the ninth example, wherein the request includes a single network slice selection assistance information (S-NSSAI) in the VPLMN and a corresponding mapped S-NSSAI in the home public land mobile network (HPLMN).

[0101] In an eleventh example, the NSACF of the tenth example, wherein the NSACF is configured to perform network slice admission control (NSAC) for single network slice selection assistance information (S-NSSAI) in the VPLMN based on an agreement between the VPLMN and a home public land mobile network (HPLMN).

[0102] In a twelfth example, a method performed by a network slice admission control function (NSACF) of a 5G core network includes maintaining a network slice quota for one or more network slices, the network slice admission control function (NSACF) configured to perform network slice admission control (NSAC) for both a visited public land mobile network (VPLMN) and a home public land mobile network (HPLMN); receiving a network slice availability check and update request for a number of registered user equipments (UEs) from an access and mobility management function (AMF); and sending a response to the AMF, the response indicating whether a maximum number of registered UEs or sessions for the S-NSSAI has been reached.

[0103] In a thirteenth example, the method of the twelfth example, the operations further include receiving a maximum number of roaming UEs per network slice for a single network slice selection assistance information (S-NSSAI) in a visited public land mobile network (VPLMN) and receiving a maximum number of roaming UEs per network slice for a corresponding mapped S-NSAAI in a home public land mobile network (HPLMN).

[0104] In a fourteenth example, the method of the twelfth example, wherein the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN) configured with a maximum number of packet data unit (PDU) sessions per network slice in local breakout mode (LBO).

[0105] In a fifteenth example, the method of the twelfth example, wherein the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN) configured with a maximum number of packet data unit (PDU) sessions per network slice in a home routed mode.

[0106] In a sixteenth example, the method of the fifteenth example, an NSACF deployed by a VPLMN is configured to perform network slice admission control (NSAC) for a single network slice selection assistance information (S-NSSAI), and an NSACF deployed by a home public land mobile network (HPLMN) is configured to perform NSAC for a corresponding mapped S-NSSAI.

[0107] In a seventeenth example, the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN), and the request is received from a session management function (SMF) deployed by the VPLMN, in the twelfth example method.

[0108] In an eighteenth example, the method of the twelfth example, wherein the quota includes a maximum number of packet data unit (PDU) sessions per network slice in local breakout (LBO) mode.

[0109] In a nineteenth example, the method of the twelfth example, wherein the quota includes a maximum number of packet data unit (PDU) sessions per network slice in home routed mode.

[0110] In a twentieth example, the method of the twelfth example, the network function is a network slice admission control function (NSACF) deployed by a visited public land mobile network (VPLMN).

[0111] In a 21st example, the 20th example method, wherein the request includes a single network slice selection assistance information (S-NSSAI) in the VPLMN and a corresponding mapped S-NSSAI in the home public land mobile network (HPLMN).

[0112] In a 22nd example, the NSACF of the 21st example method, the 10th example, is configured to perform network slice admission control (NSAC) for single network slice selection assistance information (S-NSSAI) in the VPLMN based on an agreement between the VPLMN and a home public land mobile network (HPLMN).

[0113] In a twenty-third example, the method is performed by a network slice admission control function (NSACF) of a 5G core network, the method including sending a network function registration request to a network resource function (NRF), the network function registration request including a list of single network slice selection assistance information (S-NSSAI) for which the NSACF manages admission control, and receiving a response to the network function registration request from the NRF, the NSACF being a consumer of an Nnrf_NFManagement service.

[0114] In a 24th example, the method of the 23rd example, wherein the network function registration request further includes a number of registered user equipments (UEs) supported by a first S-NSSAI of the S-NSSAIs.

[0115] In a twenty-fifth example, the method of the twenty-third example, wherein the network function registration request further includes a number of protocol data unit (PDU) sessions supported by a first S-NSSAI of the S-NSSAIs.

[0116] In a twenty-sixth example, the method of the twenty-third example, wherein the network function registration request further includes a service area for the NSACF.

[0117] In a 27th example, the method of the 23rd example further includes identifying that a number of registered user equipments (UEs) for the S-NSSAI exceed a threshold, identifying one or more AMFs associated with the S-NSSAI based on the discovery response, and sending an early admission control (EAC) flag to only the identified AMFs in response to a number of registered UEs for the S-NSSAI that exceed the threshold.

[0118] It will be appreciated by those skilled in the art that the above exemplary embodiments may be implemented in any suitable hardware or software configuration or combination thereof. Exemplary hardware platforms for implementing the exemplary embodiments may include, for example, Intel® x86-based platforms with compatible operating systems Windows OS, Mac platforms and mobile devices with operating systems such as MAC OS, iOS, Android®, etc. The exemplary embodiments of the above methods may be embodied as a program including lines of code stored in a non-transitory computer-readable storage medium that may be compiled and executed in a processor or microprocessor.

[0119] Although the application describes various embodiments, each having different features in various combinations, it will be understood by those skilled in the art that any of the features of one embodiment may be combined with the features of other embodiments in a manner not specifically disclaimed or that is not functionally or logically inconsistent with the operation or described functionality of the devices of the disclosed embodiments.

[0120] It is fully understood that use of personally identifiable information should comply with generally recognized privacy policies and practices that meet or exceed industry or governmental requirements for maintaining user privacy. In particular, personally identifiable information data should be managed and handled in a manner that minimizes the risk of unintended or unauthorized access or use, and the nature of permitted uses should be clearly indicated to users.

[0121] It will be apparent to those skilled in the art that various modifications may be made in the present disclosure without departing from the spirit or scope of the disclosure. Therefore, the present disclosure is intended to cover modifications and variations of the present disclosure within the scope of the appended claims and their equivalents.

Claims

1. A Network Slice Admission Control Function (NSACF) of a 5G core network configured to perform an operation, the operation comprising: sending a network function registration request to a network resource function (NRF), the network function registration request including a list of single network slice selection assistance information (S-NSSAI) for which the NSACF manages admission control; receiving a response to the network function registration request from the NRF, the NSACF being a consumer of an Nnrf_NFManagement service; Including, NSACF.

2. 2. The NSACF of claim 1, wherein the network capability registration request further includes a number of registered user equipments (UEs) supported by a first one of the S-NSSAIs.

3. 2. The NSACF of claim 1, wherein the network capability registration request further includes a number of protocol data unit (PDU) sessions supported by a first one of the S-NSSAIs.

4. The NSACF of claim 1 , wherein the network function registration request further includes a service area for the NSACF.

5. The operation, Identifying that a number of registered user equipments (UEs) for the S-NSSAI exceeds a threshold; Identifying one or more AMFs associated with the S-NSSAI based on a discovery response; and sending an Early Admission Control (EAC) flag to only the identified AMF in response to a number of registered UEs for the S-NSSAI exceeding the threshold; The NSACF of claim 1, further comprising:

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