WO2025092804A1

WO2025092804A1 - Method and apparatus for network slice availability check

Info

Publication number: WO2025092804A1
Application number: PCT/CN2024/128446
Authority: WO
Inventors: Cheng Wang; Antonio INIESTA GONZALEZ
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2023-10-31
Filing date: 2024-10-30
Publication date: 2025-05-08
Anticipated expiration: 2026-04-30

Abstract

Embodiments of the present disclosure provide method and apparatus for network slice availability check. A method performed by a first network node may comprise sending a first message to a network exposure node. The first message may request an availability status of a network slice, or comprise information indicating a need to check the availability status of the network slice, or subscribe to a notification about update or latest information of the availability status of the network slice.

Description

METHOD AND APPARATUS FOR NETWORK SLICE AVAILABILITY CHECK

PRIORITY CLAIM

The present application claims priority from International Application No. PCT/CN2023/128289 with the International Filing Date October 31, 2023, the disclosure of which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

The non-limiting and exemplary embodiments of the present disclosure generally relate to the technical field of communications, and specifically to methods and apparatuses for network slice availability check.

BACKGROUND

This section introduces aspects that may facilitate a better understanding of the disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.

In communication networks such as fifth generation system (5GS) as defined by 3rd Generation Partnership Project (3GPP) , a network slice may be deployed. The network slice may be a logical network that provides specific network capabilities and network characteristics. A network slice instance may be a set of network function (NF) instances and the required resources (e.g. computing, storage and networking resources) which form a deployed network slice.

Network slices may differ for supported features and network functions optimization, in which case such network slices may be identified by different network slice information e.g. Single-Network slice Selection Assistance Information (S-NSSAIs) .

Network slicing concept may be used to fulfill rich requirements from various use cases. Various network slices with different characteristics can be deployed for third party applications/users/operators as capabilities to enable various new business models. A specific network slice can be instantiated according to pre-defined or on-demand requirements for third party users/operators.

The communication networks may provide policy information to a user equipment (UE) , such as UE Route Selection Policy (URSP) as described in 3GPP TS 23.503 V18.3.0, the disclosure of which is incorporated by reference herein in its entirety. This policy may be used by the UE to determine if a detected application can be associated to an established (e.g. protocol data unit (PDU) session, can be offloaded to non-3GPP access outside a PDU session, or can trigger the establishment of a new PDU session.

For example, a part of URSP may be network slicing selection policy (NSSP) . NSSP may be used by the UE to associate the matching application with a specific network slice (e.g. S-NSSAI) . The NSSP rules may associate an application with one or more S-NSSAIs in the UE. A default rule which matches all applications to a pre-configured S-NSSAI can also be included. As such, UE can run the application using the connection setup within the designated network slice which has pre-defined features and/or quality of service (QoS) that can fulfill certain business model.

SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

URSP/NSSP can be pre-configured in the UE or be provisioned to UE from the communication networks via a policy control node. When the subscription information or UE policy or network condition changes and the network wants to control/modify the UE usage of those network slices, then the network can provision/update the UE with NSSP as a part of the URSP rules.

From UE side, when URSP rules are updated, the UE may re-evaluate the application to the (e.g. PDU) session and associated network slices and then trigger a change, if needed, of the application to (e.g. PDU) session/slice association, e.g. the application is to then be associated with another (e.g. PDU) session, or a new (e.g. PDU) session within the new slice needs to be established (that is, the connectivity of the new slice is used for the application) .

There may be various NSSAIs, such as allowed NSSAI, configured NSSAI, requested NSSAI, subscribed S-NSSAI, etc. Allowed NSSAI may indicate the S-NSSAIs values the UE could use in the serving Public Land Mobile Network (PLMN) in the current registration area. Configured NSSAI may the NSSAI provisioned in the UE applicable to one or more PLMNs. Requested NSSAI may be the NSSAI provided by the UE to the serving PLMN during registration. Subscribed S-NSSAI may be the S-NSSAI based on subscriber information, which a UE is subscribed to use in a PLMN.

There may be some use cases that third party applications may want to influence the slice selection for the connection setup between the UE running application and the application servers, so that certain features and/or QoS (bandwidth, latency, etc. ) for the running or future application can be fulfilled as application provider’s requirements.

One of such implementations could be the feature of “Application guidance for URSP determination” supported in clauses 4.15.6.7 and 4.15.6.10 of 3GPP TS 23.502 V18.3.0, the disclosure of which is incorporated by reference herein in its entirety. The feature enables an application function (AF) to provide guidance for URSP determination to fifth generation (5G) system via Network Exposure Function (NEF) . The AF may belong to the operator or to an external party and provide information on the AF guidance for URSP determination which may comprise a list of URSP rules that associate an application traffic descriptor with requested features for the candidate PDU sessions the application traffic. The policy control function (PCF) translates the service parameters values associated with expected URSP rules that are provided by the AF and sends the updated URSP to the UE accordingly.

Another example of such implementations is that Global System for Mobile communications (GSM) Association (GSMA) Official Document TS. 43, Service Entitlement Configuration, the disclosure of which is incorporated by reference herein in its entirety, is working on a new functionality called “performance Boost Upsell” which will enable UE by means of Entitlement Configure Server to request a 5G network slice for enhanced performance for specific times for any application that can use a 5G network slice provisioned by the communications service provider (CSP) . The feature leverages the use of on-demand URSP update.

The use case of on-demand requesting network slice resources (e.g. AF initiated or UE initiated) may require checking network’s current ability to support such an upsell experience for the user. For example, this may be especially relevant for devices with 5G standalone (SA) access that have the ability to offer e.g. high-speed, low-latency data connectivity to the device’s applications over certain slices which may be deployed in certain areas.

It may be important to ensure that network can confirm whether the requested slice is supported for a UE in a location (such as current location) or not, prior to the service provider of application requests URSP update for the UE towards the network and provides performance boost upsell offer to the end user. Such check can introduce better end user experience and avoid accounting misalignment.

However, it is underspecified how such slice availability check is performed.

To overcome or mitigate at least one of above mentioned problems or other problems, the embodiments of the present disclosure propose a solution for network slice availability check.

In a first aspect of the disclosure, there is provided a method performed by a first network node. The method may comprise sending a first message to a network exposure node.

In an embodiment, the first message may request an availability status of a network slice.

In an embodiment, the first message may comprise information indicating a need to check the availability status of the network slice.

In an embodiment, the first message may subscribe to a notification about update or latest information of the availability status of the network slice.

In an embodiment, the first message may comprise at least one of slice information, a user equipment (UE) identifier, or location information.

In a second aspect of the disclosure, there is provided a method performed by a second network node. The method may comprise obtaining information regarding at least one available or allowed network slice. The method may comprise determining an availability status of a network slice based on the information regarding at least one available or allowed network slice.

In a third aspect of the disclosure, there is provided a method performed by an access and mobility management node. The method may comprise receiving a third message for obtaining information regarding at least one available or allowed network slice and/or current location information for a user equipment (UE) from a second network node. The method may comprise sending a fourth message comprising the information regarding at least one available or allowed network slice and/or current location information for the UE to the second network node.

In a fourth aspect of the disclosure, there is provided method performed by a user equipment. The method may comprise receiving a message comprising an availability status of a network slice from a first network node.

In a fifth aspect of the disclosure, there is provided a first network node. The first network node may comprise a processor and a memory coupled to the processor. Said memory contains instructions executable by said processor. Said first network node is operative to send a first message to a network exposure node. The first message may request an availability status of a network slice, or comprise information indicating a need to check the availability status of the network slice, or subscribe to a notification about update or latest information of the availability status of the network slice.

In a sixth aspect of the disclosure, there is provided a second network node. The second network node comprises a processor and a memory coupled to the processor. Said memory contains instructions executable by said processor. Said second network node is operative to obtain information regarding at least one available or allowed network slice. Said second network node is operative to determine an availability status of a network slice based on the information regarding at least one available or allowed network slice.

In a seventh aspect of the disclosure, there is provided an access and mobility management node. The access and mobility management node comprises a processor and a memory coupled to the processor. Said memory contains instructions executable by said processor. Said access and mobility management node is operative to receive a third message for obtaining information regarding at least one available or allowed network slice and/or current location information for a user equipment (UE) from a second network node. Said access and mobility management node is operative to send a fourth message comprising the information regarding at least one available or allowed network slice and/or current location information for the UE to the second network node.

In an eighth aspect of the disclosure, there is provided a user equipment. The user equipment comprises a processor and a memory coupled to the processor. Said memory contains instructions executable by said processor. Said user equipment is operative to receive a message comprising the availability status of the network slice from a first network node.

In another aspect of the disclosure, there is provided a computer program product comprising instructions which when executed by at least one processor, cause the at least one processor to perform the method according to any one of the first, second, third or fourth aspect.

In another aspect of the disclosure, there is provided a computer-readable storage medium storing instructions which when executed by at least one processor, cause the at least one processor to perform the method according to any one of the first, second, third or fourth aspect.

Embodiments herein may provide many advantages, of which a non-exhaustive list of examples follows. In some embodiments herein, it may enable that a third party application or UE to get aware of whether a candidate slice is deployed/available e.g. in a certain geography area, or more specifically in the area where the UE currently is. In some embodiments herein, the third party application can use this information to decide whether or not to trigger further service processing for that UE, e.g. show a boost upsell notification for the UE to provide improved performance traffic over the requested network slice or trigger the update the URSP for that UE through the feature “Application guidance for URSP determination” . In some embodiments herein, the UE can use this information to decide whether or not to trigger UE initiated on-demand requesting network slice resources. The embodiments herein are not limited to the features and advantages mentioned above. A person skilled in the art will recognize additional features and advantages upon reading the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and benefits of various embodiments of the present disclosure will become more fully apparent, by way of example, from the following detailed description with reference to the accompanying drawings, in which like reference numerals or letters are used to designate like or equivalent elements. The drawings are illustrated for facilitating better understanding of the embodiments of the disclosure and not necessarily drawn to scale, in which:

FIG. 1a schematically shows a high level architecture in a 5G network according to an embodiment of the present disclosure;

FIG. 1b schematically shows system architecture in a 4G network according to an embodiment of the present disclosure;

FIG. 1c shows non-roaming architecture for network exposure function in reference point representation;

FIG. 1d shows non-roaming service exposure architecture for EPC-5GC Interworking;

FIG. 2 shows an example of architecture of GSMA TS. 43;

FIGs. 3a to 3e, FIGs. 4a to 4i and FIGs. 5a to 5b show flowcharts of methods according to embodiments of the present disclosure;

FIG. 6 shows a flowchart of a method according to another embodiment of the present disclosure;

FIG. 7 is a block diagram showing an apparatus suitable for practicing some embodiments of the disclosure.

DETAILED DESCRIPTION

The embodiments of the present disclosure are described in detail with reference to the accompanying drawings. It should be understood that these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitations on the scope of the present disclosure. Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present disclosure should be or are in any single embodiment of the disclosure. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Furthermore, the described features, advantages, and characteristics of the disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the disclosure may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the disclosure.

As used herein, the term “network” refers to a network following any suitable communication standards such as new radio (NR) , long term evolution (LTE) , LTE-Advanced, wideband code division multiple access (WCDMA) , high-speed packet access (HSPA) , Code Division Multiple Access (CDMA) , Time Division Multiple Address (TDMA) , Frequency Division Multiple Access (FDMA) , Orthogonal Frequency-Division Multiple Access (OFDMA) , Single carrier frequency division multiple access (SC-FDMA) and other wireless networks. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA) , etc. UTRA includes WCDMA and other variants of CDMA. A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM) . An OFDMA network may implement a radio technology such as Evolved UTRA (E-UTRA) , Ultra Mobile Broadband (UMB) , IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDMA, Ad-hoc network, wireless sensor network, etc. In the following description, the terms “network” and “system” can be used interchangeably. Furthermore, the communications between two devices in the network may be performed according to any suitable communication protocols, including, but not limited to, the communication protocols as defined by a standard organization such as 3GPP. For example, the communication protocols may comprise the first generation (1G) , 2G, 3G, 4G, 4.5G, 5G, 6G communication protocols, and/or any other protocols either currently known or to be developed in the future.

The term “network device” or “network node” or “network function” refers to any suitable function which can be implemented in a network entity (physical or virtual) of a communication network. For example, the network function can be implemented either as a network element on a dedicated hardware, as a software instance running on a dedicated hardware, or as a virtualized function instantiated on an appropriate platform, e.g. on a cloud infrastructure. For example, the 5G system (5GS) may comprise a plurality of NFs such as Access and Mobility Management Function (AMF) , Session Management Function (SMF) , Authentication Service Function (AUSF) , Unified Data Management (UDM) , Policy Control Function (PCF) , Application Function (AF) , Network Exposure Function (NEF) , User plane Function (UPF) and Network Repository Function (NRF) , radio access network (RAN) , service communication proxy (SCP) , network data analytics function (NWDAF) , network slice Selection Function (NSSF) , network slice-Specific Authentication and Authorization Function (NSSAAF) , etc. In other embodiments, the network function may comprise different types of NFs for example depending on a specific network. For example, the 4G system (such as Long Term Evolution (LTE) ) may include Mobile Management Entity (MME) , home subscriber server (HSS) , PCRF (Policy and Charging Rules Function) , PGW (Packet Data Network Gateway) , PGW control plane (PGW-C) , Serving gateway (SGW) , SGW control plane (SGW-C) , E-UTRAN Node B (eNB) , etc. In other embodiments, the network function may comprise different types of NFs for example depending on a specific network.

Virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to a provider edge node and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components (e.g., via one or more applications, components, functions, virtual machines or containers executing on one or more physical processing nodes in one or more networks) .

In some embodiments, some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines implemented in one or more virtual environments hosted by one or more of hardware nodes. Further, in embodiments in which the virtual node is not a radio access node or does not require radio connectivity (e.g., a core network node) , then the provider edge node or PE may be entirely virtualized.

The functions may be implemented by one or more applications (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc. ) operative to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein. Applications are run in virtualization environment which provides hardware comprising processing circuitry and memory. Memory contains instructions executable by processing circuitry whereby application is operative to provide one or more of the features, benefits, and/or functions disclosed herein.

Virtualization environment, comprises general-purpose or special-purpose network hardware devices comprising a set of one or more processors or processing circuitry, which may be commercial off-the-shelf (COTS) processors, dedicated Application Specific Integrated Circuits (ASICs) , or any other type of processing circuitry including digital or analog hardware components or special purpose processors. Each hardware device may comprise memory which may be non-persistent memory for temporarily storing instructions or software executed by processing circuitry. Each hardware device may comprise one or more network interface controllers (NICs) , also known as network interface cards, which include physical network interface. Each hardware device may also include non-transitory, persistent, machine-readable storage media -having stored therein software and/or instructions executable by processing circuitry. Software may include any type of software including software for instantiating one or more virtualization layers (also referred to as hypervisors) , software to execute virtual machines as well as software allowing it to execute functions, features and/or benefits described in relation with some embodiments described herein.

Virtual machines, comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer or hypervisor. Different embodiments of the instance of virtual appliance may be implemented on one or more of virtual machines, and the implementations may be made in different ways.

During operation, processing circuitry executes software to instantiate the hypervisor or virtualization layer, which may sometimes be referred to as a virtual machine monitor (VMM) . Virtualization layer may present a virtual operating platform that appears like networking hardware to virtual machine.

The term “terminal device” refers to any end device that can access a communication network and receive services therefrom. By way of example and not limitation, the terminal device refers to a mobile terminal, user equipment (UE) , or other suitable devices. The UE may be, for example, a Subscriber Station (SS) , a Portable Subscriber Station, a Mobile Station (MS) , or an Access Terminal (AT) . The terminal device may include, but not limited to, a portable computer, an image capture terminal device such as a digital camera, a gaming terminal device, a music storage and a playback appliance, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet, a wearable device, a personal digital assistant (PDA) , a portable computer, a desktop computer, a wearable terminal device, a vehicle-mounted wireless terminal device, a wireless endpoint, a mobile station, a laptop-embedded equipment (LEE) , a laptop-mounted equipment (LME) , a USB dongle, a smart device, a wireless customer-premises equipment (CPE) and the like. In the following description, the terms “terminal device” , “terminal” , “user equipment” and “UE” may be used interchangeably. As one example, a terminal device may represent a UE configured for communication in accordance with one or more communication standards promulgated by the 3GPP (3rd Generation Partnership Project) , such as 3GPP LTE standard or NR standard. As used herein, a “user equipment” or “UE” may not necessarily have a “user” in the sense of a human user who owns and/or operates the relevant device. In some embodiments, a terminal device may be configured to transmit and/or receive information without direct human interaction. For instance, a terminal device may be designed to transmit information to a network on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the communication network. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but that may not initially be associated with a specific human user.

As yet another example, in an Internet of Things (IoT) scenario, a terminal device may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another terminal device and/or network equipment. The terminal device may in this case be a machine-to-machine (M2M) device, which may in a 3GPP context be referred to as a machine-type communication (MTC) device. As one particular example, the terminal device may be a UE implementing the 3GPP narrow band internet of things (NB-IoT) standard. Particular examples of such machines or devices are sensors, metering devices such as power meters, industrial machinery, or home or personal appliances, for example refrigerators, televisions, personal wearables such as watches etc. In other scenarios, a terminal device may represent a vehicle or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation.

References in the specification to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed terms.

As used herein unless expressly stated to the contrary, the phrase “at least one of A and B” or “at least one of A or B” should be understood to mean any of the following “only A, only B, or both A and B. ” The phrase “A and/or B” should be understood to mean any of the following “only A, only B, or both A and B” .

As used herein unless expressly stated to the contrary, the phrase “aplurality of” followed by a conjunctive list of enumerated items (e.g., “A and B” , “A, B, and C” ) is intended to mean “multiple items, with each item selected from the list consisting of” the enumerated items. For example, “aplurality of A and B” is intended to mean any of the following: more than one A; more than one B; or at least one A and at least one B.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

It is noted that these terms as used in this document are used only for ease of description and differentiation among nodes, devices or networks etc. With the development of the technology, other terms with the similar/same meanings may also be used.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

Although the subject matter described herein may be implemented in any appropriate type of system using any suitable components, the embodiments disclosed herein are described in relation to a communication system complied with the exemplary system architecture illustrated in FIGs. 1a, 1b, 1c, 1d and 2. For simplicity, the system architecture of FIGs. 1a, 1b, 1c, 1d and 2 only depict some exemplary elements. In practice, a communication system may further include any additional elements suitable to support communication between terminal devices or between a wireless device and another communication device, such as a landline telephone, a service provider, or any other network node or terminal device. The communication system may provide communication and various types of services to one or more terminal devices to facilitate the terminal devices’ access to and/or use of the services provided by, or via, the communication system.

FIG. 1a schematically shows a high level architecture in a 5G network according to an embodiment of the present disclosure. For example, the fifth generation network may be 5G system (5GS) . The architecture of FIG. 1a may be similar to Figure 4.2.3-1 of 3GPP TS 23.501 V18.1.0, the disclosure of which is incorporated by reference herein in its entirety. The system architecture of FIG. 1a may comprise a plurality of network functions (NFs) such as Access and Mobility Management Function (AMF) , Session Management Function (SMF) , Authentication Service Function (AUSF) , Unified Data Management (UDM) , Policy Control Function (PCF) , Application Function (AF) , Network Exposure Function (NEF) , User plane Function (UPF) and Network Repository Function (NRF) , (radio) access network ( (R) AN) , service communication proxy (SCP) , Network Slice Selection Function (NSSF) , network slice-Specific Authentication and Authorization Function (NSSAAF) , Edge Application Server Discovery Function (EASDF) , NSACF (network slice Admission Control Function) , etc.

In accordance with an exemplary embodiment, the UE can establish a signaling connection with the AMF over the reference point N1, as illustrated in FIG. 1a. This signaling connection may enable NAS (Non-access stratum) signaling exchange between the UE and the core network, comprising a signaling connection between the UE and the (R) AN and the N2 connection for this UE between the (R) AN and the AMF. The (R) AN can communicate with the UPF over the reference point N3. The UE can establish a protocol data unit (PDU) session to the DN (data network, e.g. an operator network or Internet) through the UPF over the reference point N6.

As further illustrated in FIG. 1a, the exemplary system architecture also contains the service-based interfaces such as Nnrf, Nnef, Nausf, Nudm, Npcf, Namf, Nnsacf, Neasdf, Nnssf and Nsmf exhibited by NFs such as the NRF, the NEF, the AUSF, the UDM, the PCF, the AMF, the NSACF, the EASDF, the NSSF and the SMF. In addition, FIG. 1a also shows some reference points such as N1, N2, N3, N4, N6 and N9, which can support the interactions between NF services in the NFs. For example, these reference points may be realized through corresponding NF service-based interfaces and by specifying some NF service consumers and providers as well as their interactions in order to perform a particular system procedure.

Various NFs shown in FIG. 1a may be responsible for functions such as session management, mobility management, authentication, security, etc. The AUSF, AMF, DN, NEF, NRF, NSSF, PCF, SMF, UDM, UPF, AF, UE, (R) AN, SCP, NSACF, NSSAAF, EASDF may include the functionality for example as defined in clause 6.2 of 3GPP TS 23.501 V18.1.0.

FIG. 1b schematically shows system architecture in a 4G network according to an embodiment of the present disclosure, which is the same as Figure 4.2-1a of 3GPP TS 23.682 V18.0.0, the disclosure of which is incorporated by reference herein in its entirety. The system architecture of FIG. 1b may comprise some exemplary elements such as Services Capability Server (SCS) , Application Server (AS) , SCEF (Service Capability Exposure Function) , HSS, UE, RAN(Radio Access Network) , SGSN (Serving GPRS (General Packet Radio Service) Support Node) , MME, MSC (Mobile Switching Centre) , S-GW (Serving Gateway) , GGSN/P-GW (Gateway GPRS Support Node/PDN (Packet Data Network) Gateway) , MTC-IWF (Machine Type Communications-InterWorking Function) CDF/CGF (Charging Data Function/Charging Gateway Function) , MTC-AAA (Machine Type Communications-authentication, authorization and accounting) , SMS-SC/GMSC/IWMSC (Short Message Service-Service Centre/Gateway MSC/InterWorking MSC) IP-SM-GW (Internet protocol Short Message Gateway) . The network elements and interfaces as shown in FIG. 1b may be same as the corresponding network elements and interfaces as described in 3GPP TS 23.682 V18.0.0.

The system architecture shows the architecture for a UE used for MTC connecting to the 3GPP network (UTRAN (Universal Terrestrial Radio Access Network) , E-UTRAN (Evolved UTRAN) , GERAN (GSM EDGE (Enhanced Data rates for GSM Evolution) Radio Access Network) , etc. ) via the Um/Uu/LTE-Uu interfaces. The system architecture also shows the 3GPP network service capability exposure to SCS and AS.

As further illustrated in FIG. 1b, the exemplary system architecture also contains various reference points.

Tsms: Reference point used by an entity outside the 3GPP network to communicate with UEs used for MTC via SMS (Short Message Service) .

Tsp: Reference point used by a SCS to communicate with the MTC-IWF related control plane signaling.

T4: Reference point used between MTC-IWF and the SMS-SC in the HPLMN (home Public Land Mobile Network) .

T6a: Reference point used between SCEF and serving MME.

T6b: Reference point used between SCEF and serving SGSN.

T8: Reference point used between the SCEF and the SCS/AS.

S6m: Reference point used by MTC-IWF to interrogate HSS/HLR (Home Location Register) .

S6n: Reference point used by MTC-AAA to interrogate HSS/HLR.

S6t: Reference point used between SCEF and HSS.

SGs: Reference point used between MSC and MME.

Gi/SGi: Reference point used between GGSN/P-GW and application server and between GGSN/P-GW and SCS.

Rf/Ga: Reference point used between MTC-IWF and CDF/CGF.

Gd: Reference point used between SMS-SC/GMSC/IWMSC and SGSN.

SGd: Reference point used between SMS-SC/GMSC/IWMSC and MME.

E: Reference point used between SMS-SC/GMSC/IWMSC and MSC.

A non-terrestrial network refers to a network, or segment of networks using RF resources on board a satellite (or UAS platform) .

FIG. 1c shows non-roaming architecture for network exposure function in reference point representation, which is same as Figure 4.2.3-5 of 3GPP TS23.501 V18.1.0.3GPP Interface represents southbound interfaces between NEF and 5G core network (5GC) Network Functions e.g. N29 interface between NEF and SMF, N30 interface between NEF and PCF, etc. All southbound interfaces from NEF are not shown for the sake of simplicity. N33 is a reference point between NEF and AF.

FIG. 1d shows non-roaming service exposure architecture for EPC (Evolved Packet Core) -5GC Interworking, which is same as Figure 4.3.5.1 1 of 3GPP TS23.501 V18.1.0. If the UE is capable of mobility between EPS and 5GS, the network is expected to associate the UE with an SCEF+NEF (SCEF combined with NEF) node for Service Capability Exposure. Trust domain for SCEF+NEF is same as Trust domain for SCEF as defined in 3GPP TS 23.682 V18.0.0. EPC Interface represents southbound interfaces between SCEF and EPC nodes e.g. the S6t interface between SCEF and HSS, the T6a interface between SCEF and MME, etc. All southbound interfaces from SCEF are defined in 3GPP TS 23.682 V18.0.0 and are not shown for the sake of simplicity. 5GC Interface represents southbound interfaces between NEF and 5GC Network Functions e.g. N29 interface between NEF and SMF, N30 interface between NEF and PCF, etc. All southbound interfaces from NEF are not shown for the sake of simplicity. Interaction between the SCEF and NEF within the combined SCEF+NEF is required. For example, when the SCEF+NEF supports monitoring Application Programming Interfaces (APIs) , the SCEF and NEF need to share context and state information on a UE's configured monitoring events if the UE moves between from EPC and 5GC. The north-bound APIs which can be supported by an EPC or 5GC network are discovered by the SCEF+NEF node via the CAPIF (Common API Framework for 3GPP northbound APIs) function and/or via local configuration of the SCEF+NEF node. Different sets of APIs can be supported by the two network types.

FIG. 2 shows an example of architecture of GSMA TS. 43. The entitlement client may be a component/module on a device that provides the Voice-over-Cellular or Voice over WiFi (VoWiFi) service. The Entitlement Configuration Server may be a network element that provides entitlement configuration for different services to clients. The Entitlement Configuration Server may communicate with Business Support System (BSS) /Operation Support System (OSS) .

Entitlement refers to the applicability, availability and status of that service (or feature) on a device. GSMA TS. 43 defines a set of device-oriented APIs, corresponding server-side function ‘Entitlement Configuration Server’ and the procedures for configuring a device-based service performed during the entitlement verification step of the service or during the activation of that service.

BSS may be a software tool that is generally used by organization to manage all business activities such as processing, financial issues, etc. OSS may be a software tool that is generally used to organizations to manage their operation system or communication networks such as the networks of FIGs. 1a, 1b, 1c and 1d.

FIG. 3a shows a flowchart of a method according to an embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a first network node or communicatively coupled to the first network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 300 as well as means or modules or circuits for accomplishing other processes in conjunction with other components.

At block 302, the first network node may send a first message to a network exposure node.

The first network node may be deployed in any suitable network. In an embodiment, the first network node may be deployed in a fifth generation system (5GS) or a sixth generation system (6GS) as defined by 3GPP.

The first network node may be any suitable network device or network node or network function which may require to obtain the availability status of the network slice or may require another network node to check the availability status of the network slice or subscribe to a notification about update or latest information of the availability status of the network slice. For example, the first network node may implement application function, service entitlement server, or entitlement configure server, etc.

In an embodiment, the first network node may comprise at least one of an application function, a service entitlement server, or an entitlement configure server. The application function may be same as or similar to AF as described in 3GPP TS 23.501 V18.1.0. The entitlement configure server may be same as or similar to the entitlement configure server as described in GSMA TS. 43.

In an embodiment, the first network node may comprise Services Capability Server (SCS) or Application Server (AS) .

The network exposure node may be any suitable network device or network node or network function which can implement exposure function. For example, the network exposure node may provide means to securely expose the services, events and capabilities provided by network interfaces.

In an embodiment, the network exposure node may comprise a network exposure function (NEF) or a Service Capability Exposure Function (SCEF) or a NEF combined with SCEF. In an embodiment, the network exposure node may comprise the network exposure node which may be defined in 6GS of 3GPP.

The first message may be a new message or a modified existing message. The first message may be any suitable message which may request an availability status of a network slice, or comprise information indicating a need to check the availability status of the network slice, or subscribe to a notification about update or latest information of the availability status of the network slice.

In an embodiment, the first message may comprise at least one of a slice availability check request, a slice availability query request, a subscription request, a service parameter create request for providing guidance for UE route selection policy (URSP) determination, or a service parameter update request for providing guidance for UE URSP determination.

The guidance for UE URSP determination may be similar to “Application guidance for URSP determination” as described in clauses 4.15.6.7 and 4.15.6.10 of 3GPP TS 23.502 V18.3.0. The service parameter create request may be similar to the Nnef_ServiceParameter_Create request as described in 3GPP TS 23.502 V18.3.0. The service parameter update request may be similar to the Nnef_ServiceParameter_Update request as described in 3GPP TS 23.502 V18.3.0. The subscription request may be similar to the Nnef_EventExposure_Subscribe request as described in 3GPP TS 23.502 V18.3.0.

The first message may comprise any suitable parameter (s) for example depending on the specific type of message. For example, the first message may comprise slice information. The first message may comprise at least one filter associated with the slice information. For example, the filter may be used to specify the condition to match for the slice information.

In an embodiment, the first message may comprise at least one of slice information, a user equipment (UE) identifier, or location information. In an embodiment, the first message may comprise time information. The UE identifier, the location information and the time information may be used as the filter to specify the condition to match for the slice information.

The slice information may comprise any suitable information related to a network slice.

In an embodiment, the slice information may comprise at least one of a slice identifier, a boost type, required network capability, a boost data plan, or a subscription catalogue.

For example, the slice identifier (ID) can be an identifier that linked to the slice (e.g. boost slice) . The slice identifier ID may be an internal slice ID (e.g. S-NSSAI) or an external slice ID (e.g. External Network Slice Information (ENSI) ) .

In an embodiment, when the slice identifier ID is an external slice ID, the first network node may translate the external slice ID into the internal slice identifier ID by itself or via another network node. Then the first network node may use the internal slice ID for further processing.

In an embodiment, when the slice identifier ID is an external slice ID, the first network node may directly use the external slice ID for further processing and the translation operation may be performed by another network node which receives the external slice ID.

The boost type may indicate performance experience. For example, the boost type may be real-time interactive traffic which may enable a user to consume to a real time interactive experience.

The required network capability may indicate slice network capability e.g. as described in 5.4.4a and 5.4.4b of 3GPP TS 23.501 V18.1.0. For example, the required network capability may indicate network capability prioritization bandwidth or network capability prioritization latency, etc.

The boost data plan may indicate the data plan, such as premium data plan, unlimited data plan, etc.

The subscription catalogue may indicate the subscription catalogue e.g. Golden, Bronze, etc.

The UE identifier can be an identifier that linked to the UE. The UE identifier may be an internal UE identifier or an external UE identifier.

In an embodiment, when the UE identifier is an external UE identifier, the first network node may translate the external UE identifier into the internal UE identifier by itself or via another network node. Then the first network node may use the internal UE identifier for further processing.

In an embodiment, when the UE identifier is an external UE identifier, the first network node may directly use the external UE identifier for further processing and the translation operation may be performed by another network node which receives the external UE identifier.

In an embodiment, the UE identifier may comprise at least one of a subscription permanent identifier, a generic public subscription identifier, or an application layer identifier.

The subscription permanent identifier and the generic public subscription identifier may be same as or similar to the subscription permanent identifier (SUPI) and the generic public subscription identifier (GPSI) as described in 3GPP TS 23.501 V18.1.0.

The location information may be any suitable information such as internal location information or external location information.

In an embodiment, when the location information is external location information, the first network node may translate the external location information into the internal location information by itself or via another network node. Then the first network node may use the internal location information for further processing.

In an embodiment, when the location information is external location information, the first network node may directly use the external location information for further processing and the translation operation may be performed by another network node which receives the external location information.

For example, the location information may be the user location information as described in clause 9.3.1.16 of 3GPP TS 38.413 V17.6.0, the disclosure of which is incorporated by reference herein in its entirety.

In an embodiment, the location information may comprise at least one of a tracking area identity, a cell identity, a geographic location, or a civic address. The tracking area identity and the cell identity may be same as or similar to the tracking area identity and the cell identity as described in 3GPP TS 23.501 V18.1.0.

In an embodiment, when the first message comprises the UE identifier, the availability status of the network slice may comprise the availability status of the network slice for the UE identifier. For example, if the UE identified by the UE identifier has subscribed or been allowed to use the network slice, then the availability status of the network slice may be set as available. Otherwise the availability status of the network slice may be set as unavailable.

In an embodiment, when the first message comprises the location information, the availability status of the network slice may comprise the availability status of the network slice for a location identified by the location information. For example, if the network slice can be used in the location, then the availability status of the network slice may be set as available. Otherwise the availability status of the network slice may be set as unavailable.

In an embodiment, when the first message comprises the time information, the availability status of the network slice may comprise the availability status of the network slice for a time identified by the time information. For example, if the network slice can be used in the time, then the availability status of the network slice may be set as available. Otherwise the availability status of the network slice may be set as unavailable.

In an embodiment, when the first message comprises the UE identifier and the location information, the availability status of the network slice may comprise the availability status of the network slice for the UE identifier in the location identified by the location information.

In an embodiment, when the first message comprises the UE identifier, the time information and the location information, the availability status of the network slice may comprise the availability status of the network slice for the UE identifier in the location identified by the location information and a time identified by the time information.

FIG. 3b shows a flowchart of a method according to an embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a first network node or communicatively coupled to the first network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 310 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 312, when the first message requests the availability status of the network slice or subscribes to the notification about the update or latest information of the availability status of the network slice, the first network node may receive a second message comprising the availability status of the network slice from the network exposure node.

The second message may be a new message or a modified existing message. In an embodiment, the second message may comprise at least one of a slice availability check response, a slice availability query response, a subscription notification, a service parameter create response, or a service parameter update response.

The availability status of the network slice may indicate whether the network slice are available for example for a UE in its current location and/or in certain geography area and/or in certain time.

The second message may comprise any suitable information such as the latest UE location information.

The availability status of the network slice may be indicated in various ways such as a bit, a flag, an indicator, etc.

The availability status of the network slice may be used by the first network node for various purposes and the present disclosure has no limit on it. For example, the availability status of the network slice may be used for application node initiated or UE initiated on-demand requesting network slice resources.

For example, the availability status of the network slice may enable that a third party application to get aware of whether a candidate slice is deployed/available e.g. in a certain geography area, or more specifically in the area where the UE currently is. So that the third party application can use this information to decide whether or not to trigger further service processing for that UE, e.g. show a boost upsell notification for the UE to provide improved performance traffic over the requested network slice or trigger the update of the URSP for that UE through the feature “Application guidance for URSP determination” .

FIG. 3c shows a flowchart of a method according to an embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a first network node or communicatively coupled to the first network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 320 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 322, the first network node may generate a guidance for UE URSP determination based on the availability status of the network slice. For example, when the first network node is an application function, the first network node may generate a guidance for UE URSP determination based on the availability status of the network slice.

At block 324, the first network node may send a service parameter create or update request for providing the guidance for UE URSP determination to the network exposure node.

For example, the availability status of the network slice may enable that the application function to get aware of whether a candidate slice is deployed or available e.g. in a certain geography area or more specifically in the area where the UE currently is. So that the application function can use this information to decide whether or not to trigger further service processing for that UE, e.g. trigger the update of the URSP for that UE through the feature “Application guidance for URSP determination” .

FIG. 3d shows a flowchart of a method according to an embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a first network node or communicatively coupled to the first network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 330 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 332, the first network node may send a message comprising the availability status of the network slice to a UE. For example, when the first network node is a service entitlement server or an entitlement configure server, the first network node may send the message comprising the availability status of the network slice to a UE.

For example, the message may be sent to a service entitlement client or an entitlement configure client in the UE.

The availability status of the network slice may be used by the UE for various purposes and the present disclosure has no limit on it. For example, the availability status of the network slice may be used for UE initiated on-demand requesting network slice resources.

FIG. 3e shows a flowchart of a method according to an embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a first network node or communicatively coupled to the first network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 340 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 342, when the first message comprises the information indicating the need to check the availability status of the network slice and when the availability status of the network slice indicates the network slice is not available, the first network node may receive a message comprising information indicating the network slice is not available and/or the first message is rejected from the network exposure node. The information may be indicated in various ways such as a bit, a flag, an indicator, etc.

The message may be a new message or a modified existing message. In an embodiment, the message may comprise at least one of a service parameter create response or a service parameter update response. The message may comprise any suitable information such as the latest UE location information.

FIG. 4a shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 400 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 402, the second network node may obtain information regarding at least one available or allowed network slice.

The available or allowed network slice may indicate the slice that an UE could use e.g. in a serving PLMN e.g. in certain locations and/or in certain time period.

The second network node may be deployed in any suitable network. In an embodiment, the second network node may be deployed in a fifth generation system (5GS) as defined by 3GPP or a sixth generation system (6GS) to be defined by 3GPP.

The second network node may be any suitable network device or network node or network function which can obtain the information regarding at least one available or allowed network slice. For example, the second network node may implement application function, service entitlement server, entitlement configure server, or network exposure function, etc.

In an embodiment, the second network node may comprise at least one of an application function, a service entitlement server, an entitlement configure server, or a network exposure node.

The second network node may obtain information regarding at least one available or allowed network slice in various ways and the present disclosure has no limit on it.

The information regarding at least one available or allowed network slice may comprise at least one of information regarding at least one available or allowed network slice in a location, information regarding at least one available or allowed network slice for a UE, information regarding at least one available or allowed network slice in a time period, etc.

In an embodiment, the second network node may send a third message for obtaining information regarding at least one available or allowed network slice and/or current location information for a user equipment (UE) to an access and mobility management node and receive a fourth message comprising the information regarding at least one available or allowed network slice and/or current location information for the UE from the access and mobility management node.

In an embodiment, the second network node may obtain the access and mobility management node address which the UE (identified by the UE ID) is registered in the network from a data management node such as UDM.

The access and mobility management node may be any suitable network device or network node or network function which can implement access and mobility management.

In an embodiment, the access and mobility management node may comprise Access and Mobility Management Function (AMF) . In an embodiment, the access and mobility management node may comprise the access and mobility management node which may be defined in 6GS of 3GPP.

The third message may be a new message or a modified existing message. In an embodiment, the third message may comprise an event exposure message and the fourth message may comprise an event exposure message. For example, the third message and the fourth message may be the Namf_EventExposure service message as described in 3GPP TS 23.502 V18.3.0.

In an embodiment, the second network node may send a message for obtaining slice selection information to a network slice selection node and receive a message comprising slice selection information comprising the information regarding at least one available or allowed network slice from the network slice selection node.

The network slice selection node may be any suitable network device or network node or network function which can implement network slice selection function.

In an embodiment, the network slice selection node may comprise NSSF. In an embodiment, the network slice selection node may comprise the network slice selection node which may be defined in 6GS of 3GPP.

In an embodiment, if the availability status of the network slice for the UE identifier is to be obtained, the second network node may send a request to a data management node such as UDM and/or access and mobility management node such as AMF to obtain UE current location (e.g. TAI) . The UE current location (e.g. TAI) may be comprised in the message sent to the network slice selection node.

In an embodiment, if the availability status of the network slice for the UE identifier is to be obtained, the second network node may a request to a data management node such as UDM to obtain UE’s subscribed slice such as subscribed NSSAI. The UE’s subscribed slice may be comprised in the message sent to the network slice selection node.

In an embodiment, the second network node may map the slice ID to requested NSSAI or uses the slice ID as requested NSSAI. The requested NSSAI may be comprised in the message sent to the network slice selection node.

In an embodiment, the second network node may use requested NSSAI as subscribed NSSAI, i.e. both requested NSSAI and subscribed NSSAI are set as the requested NSSAI.

For example, the second network node may send a request to the NSSF to obtain slice selection information from the NSSF. The request can be Nnssf_NSSelection services as described in 3GPP TS 23.502 V18.3.0. For example, the request message may include Subscribed NSSAI, Requested NSSAI, TAI.

In an embodiment, the second network node may send a message for obtaining slice availability information to a network slice selection node and receive a message comprising the information regarding at least one available or allowed network slice from the network slice selection node.

For example, the second network node may either use the UE current location (e.g. TAI) or maps the location information to TAI (s) . The second network node may send the request to the NSSF to obtain the availability of the S-NSSAIs from the NSSF. The request can be Nnssf_NSSAIAvailability services as described in 3GPP TS 23.502 V18.3.0. The request message may include TAI.

At block 404, the second network node may determine an availability status of a network slice based on the information regarding at least one available or allowed network slice.

For example, if the network slice is not included in the at least one available or allowed network slice, the availability status of the network slice may be set as unavailable. Otherwise, the availability status of the network slice may be set as available.

The availability status of the network slice may comprise at least one of the availability status of the network slice in a location, the availability status of the network slice for a UE, the availability status of the network slice in a time period, etc.

Blocks 402 and 404 may be performed due to various reasons. For example, when the second network node wants to or is required by another network node to determine an availability status of a network slice, or when another network node subscribes to the second network node of a notification about update or latest information of the availability status of the network slice and a notification condition is met, blocks 402 and 404 may be performed.

FIG. 4b shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 410 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 412, the second network node may send a message for obtaining the information regarding at least one subscribed network slice for a UE to a data management node.

The data management node may be any suitable network device or network node or network function which can implement data management function, such as storing UE subscribed network slice information.

In an embodiment, the data management node may comprise UDM. In an embodiment, the data management node may comprise the data management node which may be defined in 6GS of 3GPP.

The message may be a new message or a modified existing message. For example, the second network node may send a request to obtain UE’s subscribed network slice such as subscribed NSSAI from a data management node such as UDM. For example, the request may be Nudm_SDM_Get Request as described in 3GPP TS 23.502 V18.3.0. The request message may include UE identifier such as SUPI.

At block 414, the second network node may receive a message comprising the information regarding at least one subscribed network slice for the UE from the data management node.

In an embodiment, the availability status of the network slice may be checked further based on the information regarding at least one subscribed network slice for the UE. For example, if the network slice is not included in the UE’s subscribed network slice (s) , the availability status of the network slice may be set as unavailable. Otherwise, the availability status of the network slice may be checked further based on other condition (s) .

FIG. 4c shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 420 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 422, when the second network node is an application function, the second network node may generate a guidance for UE URSP determination based on the availability status of the network slice.

For example, the guidance for UE URSP determination may be similar to the “Application guidance for URSP determination” as described in clauses 4.15.6.7 and 4.15.6.10 of 3GPP TS 23.502 V18.3.0. In other communication systems, similar application guidance for URSP determination may be provided.

At block 424, the second network node may send a service parameter create or update request for providing the guidance for UE URSP determination to a network exposure node.

For example, the service parameter create request may be similar to the Nnef_ServiceParameter_Create request as described in 3GPP TS 23.502 V18.3.0. The service parameter update request may be similar to the Nnef_ServiceParameter_Update request as described in 3GPP TS 23.502 V18.3.0.

FIG. 4d shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 430 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 432, when the second network node is a network exposure node, the second network node may receive a first message from a first network node.

In an embodiment, the first network node may comprise at least one of an application function, a service entitlement server, or an entitlement configure server.

In an embodiment, the network exposure node may comprise a network exposure function (NEF) or a Service Capability Exposure Function (SCEF) or a NEF combined with SCEF.

At block 434, the second network node may process the first message. The second network node may perform different operations for example depending on the type of first message.

For example, when the first message requests an availability status of a network slice or the first message comprises information indicating a need to check the availability status of the network slice, the second network node may obtain information regarding at least one available or allowed network slice and determine an availability status of a network slice based on the information regarding at least one available or allowed network slice.

For example, when the first message subscribes to a notification about update or latest information of the availability status of the network slice, the second network node may check a condition for triggering to determine the update or latest information of the availability status of the network slice. If the condition is matched, the second network node may obtain the information regarding at least one available or allowed network slice and determine the availability status of the network slice based on the information regarding at least one available or allowed network slice. The second network node may subscribe to a notification of UE location reporting from a data management node such as UDM and/or an access and mobility management node such as AMF. When the UE location is changed, the second network node may determine the update or latest information of the availability status of the network slice.

In an embodiment, the location information may comprise at least one of a tracking area identity, a cell identifier, a geographic location, or a civic address.

In an embodiment, when the first message comprises the UE identifier, the availability status of the network slice may comprise the availability status of the network slice for the UE identifier.

In an embodiment, when the first message comprises the location information, the availability status of the network slice may comprise the availability status of the network slice for a location identified by the location information.

In an embodiment, when the first message subscribes to the notification about the update or latest information of the availability status of the network slice and when a condition is matched, the steps of obtaining information regarding at least one available or allowed network slice and determining the availability status of the network slice based on the information regarding at least one available or allowed network slice are performed.

The condition may be any suitable condition and the present disclosure has no limit on it. In an embodiment, the condition may comprise at least one of a predefined time elapses, a UE moves a location, or a reception of a notification of the UE’s location reporting from a data management node and/or an access and mobility management node. In an embodiment, the availability status of the network slice is to be determined for the UE in the location.

The second network node may check whether the condition is matched or not. For example, the second network node may check whether the predefined time elapses. The second network node may check whether the UE moves a location. For example, the second network node may subscribe to the notification of the UE’s location reporting from the data management node and/or the access and mobility management node.

FIG. 4e shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 440 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 442, when the first message requests the availability status of the network slice or subscribes to the notification about the update or latest information of the availability status of the network slice, the second network node may send a second message comprising the availability status of the network slice to the first network node.

For example, the second network node may immediately determine the availability status of the network slice when the first message requests the availability status of the network slice or comprises information indicating a need to check the availability status of the network slice, or determine the information of the availability status of the network slice according to the subscription requirement, and then send the second message comprising the availability status of the network slice to the first network node.

FIG. 4f shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 450 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 452, the second network node may subscribe to the notification of the UE’s location reporting from the data management node and/or the access and mobility management node.

At block 454, the second network node may receive the notification of the UE’s location reporting from the data management node and/or the access and mobility management node.

For example, when the first message subscribes to the notification about the update or latest information of the availability status of the network slice, blocks 452 and 454 may be performed. When the UE’s location is changed, blocks 402 and 404 of FIG. 4a may be performed to determine the update or latest information of the availability status of the network slice. Then the second network node may send the second message comprising the update or latest availability status of the network slice to the first network node.

FIG. 4g shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 460 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 462, the second network node may receive a service parameter create or update request for providing a guidance for UE URSP determination from the first network node.

In an embodiment, the guidance for UE URSP determination may be generated based on the availability status of the network slice.

The guidance for UE URSP determination may be similar to “Application guidance for URSP determination” as described in clauses 4.15.6.7 and 4.15.6.10 of 3GPP TS 23.502 V18.3.0. The second network node may process the service parameter create or update request for example according to clauses 4.15.6.7 and 4.15.6.10 of 3GPP TS 23.502 V18.3.0.

FIG. 4h shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 470 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 472, when the first message comprises the information indicating the need to check the availability status of the network slice and the availability status of the network slice indicates unavailable, the second network node may send a message comprising information indicating the network slice is not available and/or the first message is rejected to the first network node. The message may be a new message or a modified existing message. In an embodiment, the message may be a response of the first message.

FIG. 4i shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a second network node or communicatively coupled to the second network node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 480 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 482, when the second network node is a service entitlement server or an entitlement configure server, the second network node may send a message comprising the availability status of the network slice to a UE.

The message may be a new message or a modified existing message. In an embodiment, the message may be a response of the first message. The UE may trigger on-demand requesting network slice resource based on the availability status of the network slice.

FIG. 5a shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as an access and mobility management node or communicatively coupled to the access and mobility management node. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 500 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 502, the access and mobility management node may receive a third message for obtaining information regarding at least one available or allowed network slice and/or current location information for a user equipment (UE) from a second network node.

At block 504, the access and mobility management node may send a fourth message comprising the information regarding at least one available or allowed network slice and/or current location information for the UE to the second network node.

For example, the access and mobility management node may obtain UE’s current location information and/or the available slice information (e.g. Allowed NSSAI) based on UE context information stored in the access and mobility management node.

In an embodiment, the second network node may comprise at least one of an application function, or a network exposure node.

In an embodiment, the access and mobility management node may comprises Access and Mobility Management Function (AMF) .

In an embodiment, the third message may comprise an event exposure message and the fourth message may comprise an event exposure message.

FIG. 5b shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in or at or as a user equipment or communicatively coupled to the user equipment. As such, the apparatus may provide means or modules or circuits for accomplishing various parts of the method 550 as well as means or modules or circuits for accomplishing other processes in conjunction with other components. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 552, the user equipment may receive a message comprising an availability status of a network slice from a first network node.

In an embodiment, the first network node may comprise at least one of a service entitlement server, or an entitlement configure server.

In an embodiment, the message may be received via a service entitlement client or an entitlement configure client in the UE.

In an embodiment, the user equipment may send a first message to the first network node. The first message may request an availability status of a network slice or subscribe to a notification about update or latest information of the availability status of the network slice. In an embodiment, the first message may be sent to the first network node via a service entitlement client or an entitlement configure client in the UE. In response to sending of the first message, the user equipment may receive the message comprising the availability status of the network slice from the first network node.

At block 554, optionally, the user equipment may trigger on-demand requesting network slice resource based on the availability status of the network slice.

For example, if the availability status of the network slice indicates available, the user equipment may trigger on-demand requesting network slice resource for the network slice. If the availability status of the network slice indicates unavailable, the user equipment may not trigger on-demand requesting network slice resource for the network slice.

According to various embodiments, it introduces methods and procedures of a new network exposure use case to expose the availability status of a network slice e.g. for a UE in its current location and/or in certain geography area.

FIG. 6 shows a flowchart of a method according to another embodiment of the present disclosure.

Step1. An AF or NF (e.g. entitlement configure server or service entitlement server) may request slice availability status for a slice (e.g. a boost slice identified by an externa slice ID) to NEF. The request message may include UE ID and/or location information.

In an embodiment, it may enable AF/NF and NEF as one node, while the request from AF/NF in the flow can be seen as a request from application layer (upper layer) in that node.

In an embodiment, it may enable the slice availability check request is included in other existing AF service requests, e.g. the Nnef_ServiceParameter service operations for Application guidance for URSP determination” (3GPP TS 23.502 V18.3.0 clause 4.15.6.7, 4.15.6.10) . The AF may include a new flag in the request of Application guidance for URSP determination to indicate the need to check slice availability in the target UE’s location, then the NEF may check the availability of the slice (s) provided in the URSPs in the AF request of "Application guidance for URSP determination” by performing Steps 2-7 below, before or along with proceeding business logic of the AF request of "Application guidance for URSP determination” . If the availability status of a network slice indicates unavailable, the NEF may send a message comprising information indicating the network slice is not available and/or the request is rejected to the AF.

In an embodiment, it may enable the NF or AF to subscribe to NEF of a notification about the update or latest information of slice availability status e.g. when time elapses or if the UE moves location. In this case, NEF may subscribe to the notification of UE location reporting from UDM and/or AMF (as defined in 3GPP TS 23.502 V18.3.0 clause 4.15.3) .

In an embodiment, three Options A, B and C are possible.

Option A (this option requires UE ID is included in Step1)

Step 2a. NEF sends Nudm_UECM_Get Request (UE ID) to UDM and receives Ndum_UECM_Get Response (AMF address) from UDM to obtain the AMF address which UE (identified by the UE ID) is registered in the network.

Step 3a. NEF sends the Namf_EventExposure_Subscribe request (SUPI, event=UE Slice Information) to the AMF and obtains UE’s current location information and/or the available slice information (e.g. Allowed NSSAI) based on UE context information stored in the AMF. The request can be over a new event within Namf_EventExposure services.

Option B

Steps 2b-4b. If the UE ID is included in Step 1, NEF can send a request to UDM and/or AMF, and obtain UE current location (e.g. TAI) .

Step 2b. NEF may send an Nubm_EventExposure_Get Request (SUPI, Event=Location) to UDM.

Step 3b. UDM may send an Namf_EventExposure_Subscribe Request (SUPI, Event=Location) to AMF.

Step 4b. AMF may send an Namf_EventExposur_Notify (SUPI, location (TAI) ) to NEF.

Step 5b. NEF may request UE’s subscribed NSSAI from UDM. The request may be Nudm_SDM_Get Request (SUPI) and the response may be Ndum_SDM_Get Response (subscribed NSSAI) .

Step 6b. NEF may map the slice ID (received in Step 1) to Request NSSAI or uses the slice ID as Requested NSSAI.

Optionally, NEF may use Request NSSAI as Subscribed NSSAI (e.g. both Request NSSAI and Subscribed NSSAI are set as boost slice. In this case, Step 5b is not performed) .

NEF may either use the UE current location (e.g. TAI) as obtained from Steps 2b-4b or map the location information (if received in Step1) to TAI (s) .

NEF may send the request to the NSSF to obtain slice selection information from the NSSF. The request can be Nnssf_NSSelection_Get (subscribed NSSAI, Request NSSAI, TAI) . The request message may include Subscribed NSSAI, Requested NSSAI, and TAI.

The NSSF may calculate the available slice information (e.g. Allowed NSSAI) and send it in the response to the NEF.

Option C

Steps 2c-5c are same as Option B

Step 6c. NEF may either use the UE current location (e.g. TAI) as obtained from steps 2c-4c or maps the location information (if received in Step1) to TAI (s) .

NEF may send the request to the NSSF to obtain the availability of the S-NSSAIs from the NSSF. The request can be Nnssf_NSSAIAvailability services, such as Nnssf_NSSAIAvailability_Subscribe (TAI) .

The NSSF may obtain the NSSAI availability information and send it in the response to the NEF. The response can be Nnssf_NSSAIAvailability services, such as Nnssf_NSSAIAvailability_Notify (Available NSSAI in TAI) .

Step 7. NEF checks whether the slice (e.g. the boost slice) (as received in Step 1) is included in the slice availability information as obtained from Steps 2-6, and determine the slice availability status e.g. in UE current location or in certain geography area (as received in Step 1) . NEF may additionally indicate whether the slice is already a part of UE’s subscription data, if Option A is performed or Step 5 of Option B and C is performed to retrieve UE’s slice subscription data which is crosschecked with the slice.

Step 8. NEF may send the slice availability status in the response to the NF/AF. For example, the response may be a Slice Availability Check Response which may comprise Slice ID and Slice availability status. Optionally, the response may further comprise UE ID and/or location information such as UE’s latest location information. The response may further comprise any other suitable parameter.

Step 9. If the NF/AF subscribed to notifications to NEF of notifications about the update or latest information of slice availability status if the UE moves location and NEF receives notification of UE location reporting from UDM and/or AMF, NEF may re-determine slice availability status as steps 2-7 with the new UE location (e.g. TAI) . Then NEF notifies the NF/AF with the update or latest information of slice availability status. For example, the notification may be a Slice Availability Check Notification which may comprise Slice ID and Slice availability status. Optionally, the notification may further comprise UE ID and/or location information such as UE’s latest location information. The notification may further comprise any other suitable parameter.

Some messages of FIG. 6 may be similar to the corresponding messages as described in various 3GPP specifications such as 3GPP TS 23.502 V18.3.0, etc. Some messages of FIG. 6 may be new or modified existing messages according to various embodiments of the present disclosure.

FIG. 7 is a block diagram showing an apparatus suitable for practicing some embodiments of the disclosure. For example, the first network node, the second network node, the access and mobility management node or the user equipment described above may be implemented as or through the apparatus 700.

The apparatus 700 comprises at least one processor 721, such as a digital processor (DP) , and at least one memory (MEM) 722 coupled to the processor 721. The apparatus 700 may further comprise a transmitter TX and receiver RX 723 coupled to the processor 721. The MEM 722 stores a program (PROG) 724. The PROG 724 may include instructions that, when executed on the associated processor 721, enable the apparatus 700 to operate in accordance with the embodiments of the present disclosure. A combination of the at least one processor 721 and the at least one MEM 722 may form processing means 725 adapted to implement various embodiments of the present disclosure.

Various embodiments of the present disclosure may be implemented by computer program executable by one or more of the processor 721, software, firmware, hardware or in a combination thereof.

The MEM 722 may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memories and removable memories, as non-limiting examples.

The processor 721 may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples.

In an embodiment where the apparatus is implemented as or at the first network node, the memory 722 contains instructions executable by the processor 721, whereby the first network node operates according to any of the methods performed by the first network node as described above.

In an embodiment where the apparatus is implemented as or at the second network node, the memory 722 contains instructions executable by the processor 721, whereby the second network node operates according to any of the methods performed by the second network node as described above.

In an embodiment where the apparatus is implemented as or at the access and mobility management node, the memory 722 contains instructions executable by the processor 721, whereby the access and mobility management node operates according to any of the methods performed by the access and mobility management node as described above.

In an embodiment where the apparatus is implemented as or at the user equipment, the memory 722 contains instructions executable by the processor 721, whereby the user equipment operates according to any of the methods performed by the user equipment as described above.

According to an aspect of the disclosure it is provided a computer program product being tangibly stored on a computer readable storage medium and including instructions which, when executed on at least one processor, cause the at least one processor to carry out any of the methods as described above.

According to an aspect of the disclosure it is provided a computer-readable storage medium storing instructions which when executed by at least one processor, cause the at least one processor to carry out any of the methods as described above.

In addition, the present disclosure may also provide a carrier containing the computer program as mentioned above, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium. The computer readable storage medium can be, for example, an optical compact disk or an electronic memory device like a RAM (random access memory) , a ROM (read only memory) , Flash memory, magnetic tape, CD-ROM, DVD, Blue-ray disc and the like.

The techniques described herein may be implemented by various means so that an apparatus implementing one or more functions of a corresponding apparatus described with an embodiment comprises not only prior art means, but also means for implementing the one or more functions of the corresponding apparatus described with the embodiment and it may comprise separate means for each separate function, or means that may be configured to perform two or more functions. For example, these techniques may be implemented in hardware (one or more apparatuses) , firmware (one or more apparatuses) , software (one or more modules) , or combinations thereof. For a firmware or software, implementation may be made through modules (e.g., procedures, functions, and so on) that perform the functions described herein.

Exemplary embodiments herein have been described above with reference to block diagrams and flowchart illustrations of methods and apparatuses. It will be understood that each block of the block diagrams and flowchart illustrations, and combinations of blocks in the block diagrams and flowchart illustrations, respectively, can be implemented by various means including computer program instructions. These computer program instructions may be loaded onto a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions which execute on the computer or other programmable data processing apparatus create means for implementing the functions specified in the flowchart block or blocks.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the subject matter described herein, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any implementation or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular implementations. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination.

It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The above described embodiments are given for describing rather than limiting the disclosure, and it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the disclosure as those skilled in the art readily understand. Such modifications and variations are considered to be within the scope of the disclosure and the appended claims. The protection scope of the disclosure is defined by the accompanying claims.

Claims

A method (300) performed by a first network node, comprising:

sending (302) a first message to a network exposure node,

wherein the first message requests an availability status of a network slice, or comprises information indicating a need to check the availability status of the network slice, or subscribes to a notification about update or latest information of the availability status of the network slice.
The method according to claim 1, wherein the first message comprises at least one of:

slice information,

a user equipment (UE) identifier, or

location information.
The method according to claim 2, wherein the slice information comprises at least one of:

a slice identifier,

a boost type,

required network capability,

a boost data plan, or

a subscription catalogue.
The method according to claim 2 or 3, wherein the UE identifier comprises at least one of:

a subscription permanent identifier,

a generic public subscription identifier, or

an application layer identifier.
The method according to any of claims 2-4, wherein the location information comprises at least one of:

a tracking area identity,

a cell identifier,

a geographic location, or

a civic address.
The method according to any of claims 2-5, wherein

when the first message comprises the UE identifier, the availability status of the network slice comprises the availability status of the network slice for the UE identifier,

when the first message comprises the location information, the availability status of the network slice comprises the availability status of the network slice for a location identified by the location information, and

when the first message comprises the UE identifier and the location information, the availability status of the network slice comprises the availability status of the network slice for the UE identifier in the location identified by the location information.
The method according to any of claims 1-6, wherein the first message comprises at least one of:

a slice availability check request,

a slice availability query request,

a subscription request,

a service parameter create request for providing guidance for UE route selection policy (URSP) determination, or

a service parameter update request for providing guidance for UE URSP determination.
The method according to any of claims 1-7, wherein when the first message requests the availability status of the network slice or subscribes to the notification about the update or latest information of the availability status of the network slice, the method further comprises:

receiving (312) a second message comprising the availability status of the network slice from the network exposure node.
The method according to claim 8, further comprising:

generating (322) a guidance for UE URSP determination based on the availability status of the network slice; and

sending (324) a service parameter create or update request for providing the guidance for UE URSP determination to the network exposure node.
The method according to claim 8 or 9, further comprising:

sending (332) a message comprising the availability status of the network slice to a UE.
The method according to any of claims 1-10, wherein when the first message comprises the information indicating the need to check the availability status of the network slice and the availability status of the network slice indicates the network slice is not available, the method further comprises:

receiving (342) a message comprising information indicating the network slice is not available and/or the first message is rejected from the network exposure node.
The method according to any of claims 1-11, wherein the first network node comprises at least one of:

an application function,

a service entitlement server, or

an entitlement configure server.
The method according to any of claims 1-12, wherein the network exposure node comprises a network exposure function (NEF) or a Service Capability Exposure Function (SCEF) or a NEF combined with SCEF.
A method (400) performed by a second network node, comprising:

obtaining (402) information regarding at least one available or allowed network slice; and

determining (404) an availability status of a network slice based on the information regarding at least one available or allowed network slice.
The method according to claim 14, wherein the obtaining information regarding at least one available or allowed network slice comprises:

sending a third message for obtaining information regarding at least one available or allowed network slice and/or current location information for a user equipment (UE) to an access and mobility management node; and

receiving a fourth message comprising the information regarding at least one available or allowed network slice and/or current location information for the UE from the access and mobility management node.
The method according to claim 15, wherein the access and mobility management node comprises Access and Mobility Management Function (AMF) .
The method according to claim 15 or 16, wherein the third message comprises an event exposure message and the fourth message comprises an event exposure message.
The method according to any of claims 14-17, wherein the obtaining information regarding at least one available or allowed network slice comprises:

sending a message for obtaining slice selection information to a network slice selection node; and

receiving a message comprising slice selection information comprising the information regarding at least one available or allowed network slice from the network slice selection node.
The method according to any of claims 14-18, wherein the obtaining information regarding at least one available or allowed network slice comprises:

sending a message for obtaining slice availability information to a network slice selection node; and

receiving a message comprising the information regarding at least one available or allowed network slice from the network slice selection node.
The method according to any of claims 14-19, further comprising:

sending (412) a message for obtaining the information regarding at least one subscribed network slice for a UE to a data management node; and

receiving (414) a message comprising the information regarding at least one subscribed network slice for the UE from the data management node.
The method according to claim 20, wherein the availability status of the network slice is checked further based on the information regarding at least one subscribed network slice for the UE.
The method according to any of claims 14-21, wherein the second network node comprises at least one of:

an application function,

a service entitlement server,

an entitlement configure server, or

a network exposure node.
The method according to any of claims 14-22, wherein when the second network node is an application function, the method further comprises:

generating (422) a guidance for UE URSP determination based on the availability status of the network slice; and

sending (424) a service parameter create or update request for providing the guidance for UE URSP determination to a network exposure node.
The method according to any of claims 14-23, wherein when the second network node is a network exposure node, the method further comprises:

receiving (432) a first message from a first network node; and

processing (434) the first message,

wherein the first message requests an availability status of a network slice, or comprises information indicating a need to check the availability status of the network slice, or subscribes to a notification about update or latest information of the availability status of the network slice.
The method according to claim 24, wherein the first message comprises at least one of:

slice information,

a user equipment (UE) identifier, or

location information.
The method according to claim 25, wherein the slice information comprises at least one of:

a slice identifier,

a boost type,

required network capability,

a boost data plan, or

a subscription catalogue.
The method according to claim 25 or 26, wherein the UE identifier comprises at least one of:

a subscription permanent identifier,

a generic public subscription identifier, or

an application layer identifier.
The method according to any of claims 25-27, wherein the location information comprises at least one of:

a tracking area identity,

a cell identifier,

a geographic location, or

a civic address.
The method according to any of claims 25-28, wherein

when the first message comprises the UE identifier, the availability status of the network slice comprises the availability status of the network slice for the UE identifier,

when the first message comprises the location information, the availability status of the network slice comprises the availability status of the network slice for a location identified by the location information, and

when the first message comprises the UE identifier and the location information, the availability status of the network slice comprises the availability status of the network slice for the UE identifier in the location identified by the location information.
The method according to any of claims 24-29, wherein the first message comprises at least one of:

a slice availability check request,

a slice availability query request,

a subscription request,

a service parameter create request for providing guidance for UE route selection policy (URSP) determination, or

a service parameter update request for providing guidance for UE URSP determination.
The method according to any of claims 24-30, wherein when the first message requests the availability status of the network slice or subscribes to the notification about the update or latest information of the availability status of the network slice, the method further comprises:

sending (442) a second message comprising the availability status of the network slice to the first network node.
The method according to claim 31, further comprising:

receiving (462) a service parameter create or update request for providing a guidance for UE URSP determination from the first network node,

wherein the guidance for UE URSP determination is generated based on the availability status of the network slice.
The method according to any of claims 24-32, wherein when the first message subscribes to the notification about the update or latest information of the availability status of the network slice,

when a condition is matched, the steps of obtaining information regarding at least one available or allowed network slice and determining the availability status of the network slice based on the information regarding at least one available or allowed network slice are performed.
The method according to claim 33, wherein the condition comprises at least one of:

a predefined time elapses,

a UE moves a location, or

a reception of a notification of the UE’s location reporting from a data management node and/or an access and mobility management node,

wherein the availability status of the network slice is to be determined for the UE in the location.
The method according to claim 34, further comprising:

subscribing (452) to the notification of the UE’s location reporting from the data management node and/or the access and mobility management node; and

receiving (454) the notification of the UE’s location reporting from the data management node and/or the access and mobility management node.
The method according to any of claims 24-35, wherein when the first message comprises the information indicating the need to check the availability status of the network slice and the availability status of the network slice indicates unavailable, the method further comprises:

sending (472) a message comprising information indicating the network slice is not available and/or the first message is rejected to the first network node.
The method according to any of claims 24-36, wherein the first network node comprises at least one of:

an application function,

a service entitlement server, or

an entitlement configure server.
The method according to any of claims 24-37, wherein the network exposure node comprises a network exposure function (NEF) or a Service Capability Exposure Function (SCEF) or a NEF combined with SCEF.
The method according to any of claims 14-22, wherein when the second network node is a service entitlement server or an entitlement configure server, the method further comprises:

sending (482) a message comprising the availability status of the network slice to a UE.
A method (500) performed by an access and mobility management node, comprising:

receiving (502) a third message for obtaining information regarding at least one available or allowed network slice and/or current location information for a user equipment (UE) from a second network node; and

sending (504) a fourth message comprising the information regarding at least one available or allowed network slice and/or current location information for the UE to the second network node.
The method according to claim 40, wherein the second network node comprises at least one of:

an application function, or

a network exposure node.
The method according to claim 41, wherein the network exposure node comprises a network exposure function (NEF) or a Service Capability Exposure Function (SCEF) or a NEF combined with SCEF.
The method according to any of claims 40-42, wherein the access and mobility management node comprises Access and Mobility Management Function (AMF) .
The method according to any of claims 40-43, wherein the third message comprises an event exposure message and the fourth message comprises an event exposure message.
A method (550) performed by a user equipment, comprising:

receiving (552) a message comprising an availability status of a network slice from a first network node.
The method according to claim 45, further comprising:

triggering (554) on-demand requesting network slice resource based on the availability status of the network slice.
The method according to claim 45 or 46, wherein the first network node comprises at least one of:

a service entitlement server, or

an entitlement configure server.
The method according to any of claims 45-47, wherein the message is received via a service entitlement client or an entitlement configure client in the UE.
A first network node (700) , comprising:

a processor (721) ; and

a memory (722) coupled to the processor (721) , said memory (722) containing instructions executable by said processor (721) , whereby said first network node (700) is operative to:

send a first message to a network exposure node,

wherein the first message requests an availability status of a network slice, or comprises information indicating a need to check the availability status of the network slice, or subscribes to a notification about update or latest information of the availability status of the network slice.
The first network node according to claim 49, wherein the first network node is further operative to perform the method of any one of claims 2 to 13.
A second network node (700) , comprising:

a processor (721) ; and

a memory (722) coupled to the processor (721) , said memory (722) containing instructions executable by said processor (721) , whereby said second network node (700) is operative to:

obtain information regarding at least one available or allowed network slice; and

determine an availability status of a network slice based on the information regarding at least one available or allowed network slice.
The second network node according to claim 51, wherein the second network node is further operative to perform the method of any one of claims 15 to 39.
An access and mobility management node (700) , comprising:

a processor (721) ; and

a memory (722) coupled to the processor (721) , said memory (722) containing instructions executable by said processor (721) , whereby said access and mobility management node (700) is operative to:

receive a third message for obtaining information regarding at least one available or allowed network slice and/or current location information for a user equipment (UE) from a second network node; and

send a fourth message comprising the information regarding at least one available or allowed network slice and/or current location information for the UE to the second network node.
The access and mobility management node according to claim 53, wherein the access and mobility management node is further operative to perform the method of any one of claims 41 to 44.
A user equipment (700) , comprising:

a processor (721) ; and

a memory (722) coupled to the processor (721) , said memory (722) containing instructions executable by said processor (721) , whereby said user equipment (700) is operative to:

receive a message comprising the availability status of the network slice from a first network node.
The user equipment according to claim 55, wherein the user equipment is further operative to perform the method of claims 46 to 48.
A computer-readable storage medium storing instructions which when executed by at least one processor, cause the at least one processor to perform the method according to any one of claims 1 to 48.
A computer program product comprising instructions which when executed by at least one processor, cause the at least one processor to perform the method according to any one of claims 1 to 48.