Patent Description:
For the purposes of the present document, the terms and definitions given in 3GPP Technical Report (TR) <NUM> [<NUM>] and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in 3GPP TR <NUM> [<NUM>].

Network slicing features defined in 3GPP release <NUM> and release <NUM> enable a great variety of communication services for operators and verticals alike. To enhance the commercial viability of Network Slicing, GSMA 5GJA has introduced in document NG. <NUM> the concept of Generic Slice Template [<NUM>] from which several Network Slice Types descriptions can be derived. Some of the parameters in the GST point explicitly to the definition of parameters and bounds on the service delivered to the end customer. However, the enforcement of some of these bounds or of some of these parameters is not supported by the 5GS yet.

For instance, the GST aims at the limitation of the number of PDU sessions per slice, or the number of devices supported per network slice, or the maximum UL or DL data rate per network slice (which is not the same as the AMBR for a UE, rather a rate limitation per UE/S-NSSAI). These parameters cannot be enforced today as the system lacks the ability to do so.

The SA2 SID on Enhancement of Network Slicing Phase <NUM> [<NUM>] aims at identifying the gaps that need to be filled in providing support for the GST parameters enforcement and the suitable solution to address these gaps.

The objective of this study is to identify the gaps in the currently defined 5GS system procedures defined in SA2 owned Technical Specifications to support of GST parameters and to study potential solutions that may address these gaps. The following parameters at least will be under consideration:.

Interaction with SA1 and GSMA is expected for any aspects that need any clarification, as identified as the work progresses.

3GPP SA2 Working Group has already started the study on how to support the Generic Slice Template (GST) parameters monitoring, control and enforcement however, the issue with the Service Level Agreement (SLA) quota on the maximum number of UEs per Network Slice in roaming has not been resolved yet. This disclosure proposes solution on how to monitor, control and enforce the SLA quota on maximum number of UEs per Network Slice in roaming.

<CIT> discloses a communication network arrangement comprising one or more network slices of a communication network, a quota monitoring component and a management component, wherein the quota monitoring component is configured to detect whether a quota which limits the maximum number of mobile terminals registered in a network slice and/or the maximum number of sessions provided in the network slice has been reached, the quota monitoring component is configured to notify the management component if the quota has been reached and the management component is configured to reject a request of a mobile terminal for registration to the network slice or establishment of a session in the network slice if the quota has been reached.

The present invention provides a Network Function node, a controlling method for a Network Function node, a core network node and a controlling method for a core network node as set out in the appended independent claims. Optional features are defined in the dependent claims. According to an aspect of the present disclosure, a Network Function node for network slice quota, includes: means for managing a number of user equipment, UE, registered in a network slice; means for receiving a first request, from a core network node in a core network, for checking availability of the network slice, including information indicating the network slice; means for checking the availability of the network slice in accordance with the number of UE registered in the network slice; and means for sending, to the core network node, a first response to the first request, indicating the availability, wherein the first response causes the core network node to reject a registration procedure for UE based on the number of UE registered in the network slice, wherein, the core network node is included in a visited Public Land Mobile Network, PLMN, wherein the means for receiving are configured to receive an update flag, from the core network node, indicating that the number of UE registered in the network slice is to be decreased, and wherein the Network Function node further comprising means for decreasing the number of UE registered in the network slice based on the update flag.

According to another aspect of the present disclosure, a core network node for a core network, includes: means for sending a first request, to a network function node for network slice quota configured to manage a number of user equipment, UE, registered in a network slice, including information indicating the network slice; means for receiving, from the network function node for network slice quota, a first response to the first request, indicating the availability, means for rejecting a registration procedure for UE based on the network slice quota on the number of UE per registered in the network slice in response to the first response; wherein the core network node is included in a visited Public Land Mobile Network, PLMN, wherein the checking is performed by the Network Function node for network slice quota, in accordance with the number of UE registered in the network slice, and wherein the means for sending are configured to send an update flag, from the core network node, indicating that the number of UE registered in the network slice is to be decreased.

According to another aspect of the present disclosure, a controlling method for a Network Function node for network slice quota, the controlling method includes: managing a number of user equipment, UE, registered in a network slice; receiving a first request, from a core network node in a core network, for checking availability of the network slice, including information indicating the network slice; checking the availability of the network slice in accordance with the number of UE registered in the network slice; sending, to the core network node, a first response to the first request, indicating the availability, wherein the first response causes the core network node to reject a registration procedure for UE based on the number of UE registered in the network slice, wherein, the core network node is included in a visited Public Land Mobile Network, PLMN, wherein receiving the first request comprises receiving an update flag, from the core network node, indicating that the number of UE registered in the network slice is to be decreased, and wherein the controlling method for a Network Function node further comprising decreasing the number of UE registered in the network slice based on the update flag.

According to another aspect of the present disclosure, a controlling method for a core network node in a core network, the controlling method includes: sending a first request, to a network function node for network slice quota configured to manage a number of user equipment, UE, registered in a network slice, for checking availability of the network slice, including information indicating the network slice; receiving, from the network function node for network slice quota, a first response to the first request, indicating the availability, rejecting a registration procedure for UE based on the network slice quota on the number of UE per registered in the network slice in response to the first response, wherein the core network node is included in a visited Public Land Mobile Network, PLMN, wherein the checking is performed by the Network Function node for network slice quota, in accordance with the network slice quota on the number of UE per network slice, and wherein sending the first request comprises sending an update flag, from the core network node, indicating that the number of UE registered in the network slice is to be decreased.

Network Slice Quota management during roaming.

This example aspect describes an exemplary way to monitor, control and enforce the SLA quota restrictions on maximum number of UEs per Network Slice in roaming. A new Network Slice Quota (NSQ) service is proposed which assumes that the Network Slice Quota is managed by a designated network function (e.g. NSQ - Network Slice Quota function/entity or any other notation for a function or entity which monitors, controls and enforces the maximum numbers of UEs per Network Slice quota (e.g. Service Level Agreements (SLA)). This new NSQ can be a new functional entity within any existing network node, e.g. NSSF, AMF, PCF, NWDAF or NSQ can be implemented as a new physical entity). The following Network Slice Quota (NSQ) Service, NSQ operations and potential NSQ service consumers are proposed in Table <NUM> which are applicable in both cases where the NSQ is represented as a part of an existing network node or it is represented as a new designated network node.

<FIG> illustrates in more detail the newly defined Network Slice Quota (NSQ) <NUM> service and operations.

In some example aspects, a new parameter "notification parameter" for indicating the triggers for the Notification, for example, periodic notification, threshold based notification, and event based notification and etc., can be included as parameters.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota management during roaming by the home PLMN (hPLMN), i.e. by the home Network Slice Quota (hNSQ <NUM>) function which can be a new functional entity implemented as a new network node or a functional entity within any existing network node (e.g. NSSF <NUM>, AMF <NUM>, PCF, NWDAF). Third party AF (e.g. AF1 and AF2 in <FIG>) may have associations with the hNSQ <NUM> of the hPLMN. In roaming, the global Network Slice Quota (e.g. number of UEs per network slice) is counted by the hNSQ <NUM> in the hPLMN using N8 interface. The hNSQ <NUM> entity can be a new functional entity within any existing network node, e.g. hNSSF <NUM>, hAMF <NUM>, hPCF, hNWDAF or hNSQ <NUM> can be implemented as a new designated network node.

<FIG> illustrates schematically an exemplary procedure for UEs per Network Slice quota management and enforcement in the hPLMN. The global quota is made available in the hPLMN by the CAM <NUM> or the Service provider (e.g. AF). In roaming, the quota is managed and enforced by the hNSQ <NUM> of the hPLMN.

<FIG> illustrates schematically an exemplary procedure for "number of UEs per S-NSSAI_1" quota availability check with the hNSQ <NUM> /hNSSF <NUM> in roaming for Model <NUM>. The procedure is equally valid for the case of one or more S-NSSAI(s).

The "number of UE(s) per network slice" quota status indicates 'no quota available' if the number of UEs per S-NSSAI_1 exceeds the max number of UEs per S-NSSAI_1 quota.

The "number of UE(s) per network slice" quota status indicates `quota available' if the number of UEs per S-NSSAI_1 does not exceed the max number of UEs per S-NSSAI_1 quota. step <NUM>). The hUDM <NUM> forwards the Nnsq/nssf_NetworkSliceQuota_Availability Response (S-NSSAI_1, NSQ quota status = "number of UE(s) per network slice" quota status) message to the vAMF <NUM>.

Note that if the service function as described in step <NUM>) resides in the hUDM <NUM>, then both step <NUM>) and step <NUM>) can be considered as interfaces between service functions within the hUDM <NUM>.

<FIG> illustrates schematically an exemplary procedure for "number of UEs per S-NSSAI_1" quota update with the hNSQ <NUM> /hNSSF <NUM> in roaming for Model <NUM>. The procedure is equally valid for the case of one or more S-NSSAI(s).

<FIG> illustrates schematically an exemplary architecture for Network Slice Quota management during roaming by the visiting PLMN (vPLMN), i.e. the visiting Network Slice Quota (vNSQ) function which can be a new functional entity implemented as a new network node or a functional entity within any existing network node (e.g. vNSSF, vAMF, vPCF, vNWDAF). Third party AFs have associations with the CAM system in each PLMN (i.e. home and visiting). The home quota is counted in hPLMN, i.e. the roaming quota is counted in the vPLMN. The global quota is counted in the AF by querying to all associated NSQs in both hPLMN and vPLMNs.

<FIG> illustrate in more detail UEs per network slice quota management and enforcement in the vPLMN. The Service Provider (e.g. AF) allocates quota for each vPLMN(s) including the hPLMN. The global quota is updated in the AF by interrogating to the associated NSQs in each PLMNs.

<FIG> illustrates schematically an exemplary procedure for Number of UEs per network slice quota update with the vNSQ <NUM> /vNSSF <NUM> in roaming (Model <NUM>), in which:.

The "number of UE(s) per network slice" quota status indicates 'no quota available' if the number of UEs per S-NSSAI_1 exceeds the max number of UEs per S-NSSAI_1 quota. The "number of UE(s) per network slice" quota status indicates `quota available' if the number of UEs per S-NSSAI_1 does not exceed the max number of UEs per S-NSSAI_1 quota.

In case there is a Node_Id but no UE_Id(s) and the update_flag is set to "decrement" in the Nnsq/nssf_NetworkSliceQuota_Update Request message, the NSQ/NSSF decrements the number of registered UE(s) in the NSQ <NUM> /NSSF <NUM> which are associated with the Node_Id.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota Subscribe/Unsubscribe to the NSQ <NUM> (Model <NUM>), in which:
step <NUM>). The CAM <NUM> sends the Nnsq/ nssf_NetworkSliceQuota_Subscribe/Unsubscribe (S-NSSAI(s), type of NSQ service = "number UEs per network slice" quota, type of NSQ service = "number of PDU sessions per network slice" quota) to the NSQ <NUM>, a new parameter "notification parameter" for indicating the triggers for the Notification, for example, periodic notification, threshold based notification, and event based notification and etc., can be included as parameters.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota Availability check to the NSQ <NUM> (Model <NUM>), in which:.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota update to the NSQ <NUM> (Model <NUM>), in which:.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota notify to the OAM <NUM> (Model <NUM>), in which:
step <NUM>). Nnsq/nssf_NetworkSliceQuota_Notify (S-NSSAI(s), NSQ quota status = "number of UEs per network slice" quota status, NSQ quota status = "number of PDU sessions per network slice" quota status) - The NSQ <NUM> /NSSF <NUM> sends a notification about the network slice quota status (NSQ quota status). The NSQ <NUM> /NSSF <NUM> includes as a parameter S-NSSAI(s) for which the reported quota status is applicable, e.g. the S-NSSAI_1 along with the available quota, e.g. "number of UEs per network slice" quota status (NSQ quota status). The notification could be triggered periodically or triggered by an event or threshold based on the notification subscription by the OAM <NUM>.

<FIG> illustrates schematically an exemplary architecture for Network Slice Quota management during roaming by the AF <NUM> via the NEF <NUM>. Third party AFs (e.g. AF1 and AF2) have respective associations with the NSQ <NUM> in each PLMN via the NEF <NUM>. The global quota is counted by the AF <NUM> via interworking with the NEF <NUM> in each PLMN.

<FIG> illustrate in detail UEs per network slice quota management and enforcement in the vPLMN. The Service Provider (e.g. AF) allocates quota for each vPLMN(s) including the hPLMN. The global quota is updated in the AF <NUM> by interrogating to the associated NSQs <NUM> via the NEF <NUM> in each PLMNs.

In case there is a Node_Id but no UE_Id(s) and the update_flag is set to "decrement" in the Nnsq/nssf_NetworkSliceQuota_Update Request message, the NSQ <NUM> /NSSF <NUM> decrements the number of registered UE(s) in the NSQ <NUM> /NSSF <NUM> which are associated with the Node_Id.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota information subscription by the AF <NUM> via the NEF <NUM> (Model <NUM>), in which:.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota availability check by the AF <NUM> via the NEF <NUM> (Model <NUM>), in which:.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota update by the AF <NUM> via the NEF <NUM> (Model <NUM>), in which:.

<FIG> illustrates schematically an exemplary procedure for Network Slice Quota Notification to the AF <NUM> via the NEF <NUM> (Model <NUM>), in which:.

Beneficially, the above described example aspects include, although they are not limited to, one or more of the following functionalities:.

Number of UEs per network slice monitoring, update and enforcement in roaming by the vPLMN. The global quota is distributed between all PLMNs (hPLMN and vPLMNs). The quota in roaming is managed by the vNSQ separately by the rest of the quotas (i.e. managed pervPLMN). The quota in the vPLMN may optionally be regularly notified to the hPLMN.

In order to provide these functionalities, the above example aspects describe exemplary methods comprising (at least some of) the following steps.

Number of UEs per network slice monitoring, update and enforcement in roaming by the Service Provider's Application (AF). The AF subscribes for Network Slice Quota services of quota availability check, quota update and quota notification with the NSQ and accesses these services via the NEF.

The above described example aspects allow for monitoring and control of the number of the UEs registered in a Network Slices in roaming. The example aspects also allow enforcing access and service restrictions in a network slice for roaming UEs when the maximum number of UEs per network slice quota is reached.

<FIG> schematically illustrates a mobile (cellular or wireless) telecommunication system <NUM> to which the above example aspects are applicable.

In this network, users of mobile devices <NUM> (UEs) can communicate with each other and other users via respective base stations <NUM> and a core network <NUM> using an appropriate 3GPP radio access technology (RAT), for example, an E-UTRA and/or <NUM> RAT. It will be appreciated that a number of base stations <NUM> form a (radio) access network or (R)AN. As those skilled in the art will appreciate, whilst one mobile device <NUM> and one base station <NUM> (RAN) are shown in <FIG> for illustration purposes, the system, when implemented, will typically include other base stations and mobile devices (UEs).

Each base station <NUM> controls one or more associated cells (either directly or via other nodes such as home base stations, relays, remote radio heads, distributed units, and/or the like). A base station <NUM> that supports E-UTRA/<NUM> protocols may be referred to as an 'eNB' and a base station <NUM> that supports Next Generation/<NUM> protocols may be referred to as a 'gNBs'. It will be appreciated that some base stations <NUM> may be configured to support both <NUM> and <NUM>, and/or any other 3GPP or non-3GPP communication protocols.

The mobile device <NUM> and its serving base station <NUM> are connected via an appropriate air interface (for example the so-called 'Uu' interface and/or the like). Neighbouring base stations <NUM> are connected to each other via an appropriate base station to base station interface (such as the so-called 'X2' interface, 'Xn' interface and/or the like). The base station <NUM> is also connected to the core network nodes via an appropriate interface (such as the so-called `S1', 'N2', 'N3' interface, and/or the like). Non-Access-Stratum (NAS) interface (such as the so-called `N1' interface, and/or the like) is connected between the mobile device <NUM> and the core network node via the base station <NUM>.

The core network <NUM> typically includes logical nodes (or 'functions') for supporting communication in the telecommunication system <NUM>. Typically, for example, the core network <NUM> of a `Next Generation' / <NUM> system will include, amongst other functions, control plane functions (CPFs) and user plane functions (UPFs). It will be appreciated that the core network <NUM> may also include, amongst others: a Network Exposure Function (NEF) <NUM>, an Access and Mobility Management Function (AMF) <NUM>; a Network Slice Quota (NSQ) <NUM> / Network Slice Selection Function (NSSF) <NUM>; and a Unified Data Management (UDM) function <NUM>. The core network <NUM> is also couple to at least one Application Function (AF) <NUM> and an Operations and Maintenance (OAM) entity <NUM>. From the core network <NUM>, connection to an external IP network / data network <NUM> (such as the Internet) is also provided.

The components of this system <NUM> are configured to perform one or more of the above described example aspects.

<FIG> is a block diagram illustrating the main components of the UE (mobile device <NUM>) shown in <FIG>. As shown, the UE includes a transceiver circuit <NUM> which is operable to transmit signals to and to receive signals from the connected node(s) via one or more antenna <NUM>. Although not necessarily shown in <FIG>, the UE will of course have all the usual functionality of a conventional mobile device (such as a user interface <NUM>) and this may be provided by any one or any combination of hardware, software and firmware, as appropriate. A controller <NUM> controls the operation of the UE in accordance with software stored in a memory <NUM>. The software may be pre-installed in the memory <NUM> and/or may be downloaded via the telecommunication network <NUM> or from a removable data storage device (RMD), for example. The software includes, among other things, an operating system <NUM> and a communications control module <NUM>. The communications control module <NUM> is responsible for handling (generating/sending/receiving) signaling messages and uplink/downlink data packets between the UE <NUM> and other nodes, including (R)AN nodes <NUM>, application functions, and core network nodes. Such signaling includes appropriately formatted requests and responses relating to network slice quota management.

<FIG> is a block diagram illustrating the main components of an exemplary (R)AN node <NUM> (base station) shown in <FIG>. As shown, the (R)AN node <NUM> includes a transceiver circuit <NUM> which is operable to transmit signals to and to receive signals from connected UE(s) <NUM> via one or more antenna <NUM> and to transmit signals to and to receive signals from other network nodes (either directly or indirectly) via a network interface <NUM>. The network interface <NUM> typically includes an appropriate base station - base station interface (such as X2/Xn) and an appropriate base station - core network interface (such as S1/N2/N3). A controller <NUM> controls the operation of the (R)AN node <NUM> in accordance with software stored in a memory <NUM>. The software may be pre-installed in the memory <NUM> and/or may be downloaded via the telecommunication network <NUM> or from a removable data storage device (RMD), for example. The software includes, among other things, an operating system <NUM> and a communications control module <NUM>. The communications control module <NUM> is responsible for handling (generating/sending/ receiving) signaling between the (R)AN node <NUM> and other nodes, such as the UE <NUM>, the AF <NUM>, the CAM <NUM>, and the core network nodes. Such signaling includes appropriately formatted requests and responses relating to network slice quota management.

<FIG> is a block diagram illustrating the main components of a generic core network node (or function) shown in <FIG>, for example, the NEF <NUM>, the AMF <NUM>, the NSQ/NSSF <NUM>/<NUM>, and the UDM <NUM>. It will be appreciated that the same block diagram may be applicable to the AF <NUM>, and the CAM entity <NUM>. As shown, the core network node includes a transceiver circuit <NUM> which is operable to transmit signals to and to receive signals from other nodes (including the UE <NUM> and the (R)AN node <NUM>) via a network interface <NUM>. A controller <NUM> controls the operation of the core network node in accordance with software stored in a memory <NUM>. The software may be pre-installed in the memory <NUM> and/or may be downloaded via the telecommunication network <NUM> or from a removable data storage device (RMD), for example. The software includes, among other things, an operating system <NUM> and at least a communications control module <NUM>. The communications control module <NUM> is responsible for handling (generating/sending/ receiving) signaling between the core network node and other nodes, such as the UE <NUM>, (R)AN node <NUM>, and other core network nodes. Such signaling includes appropriately formatted requests and responses relating to network slice quota management.

Detailed example aspects have been described above. As those skilled in the art will appreciate, a number of modifications and alternatives can be made to the above example aspects whilst still benefiting from the disclosure embodied therein. By way of illustration only a number of these alternatives and modifications will now be described.

In the above description, the UE, the (R)AN node, and the core network node are described for ease of understanding as having a number of discrete modules (such as the communication control modules). Whilst these modules may be provided in this way for certain applications, for example where an existing system has been modified to implement the above example aspects, in other applications, for example in systems designed with the inventive features in mind from the outset, these modules may be built into the overall operating system or code and so these modules may not be discernible as discrete entities. These modules may also be implemented in software, hardware, firmware or a mix of these.

Each controller may comprise any suitable form of processing circuitry including (but not limited to), for example: one or more hardware implemented computer processors; microprocessors; central processing units (CPUs); arithmetic logic units (ALUs); input/output (IO) circuits; internal memories / caches (program and/or data); processing registers; communication buses (e.g. control, data and/or address buses); direct memory access (DMA) functions; hardware or software implemented counters, pointers and/or timers; and/or the like.

In the above example aspects, a number of software modules were described. As those skilled in the art will appreciate, the software modules may be provided in compiled or un-compiled form and may be supplied to the UE, the (R)AN node, and the core network node as a signal over a computer network, or on a recording medium. Further, the functionality performed by part or all of this software may be performed using one or more dedicated hardware circuits. However, the use of software modules is preferred as it facilitates the updating of the UE, the (R)AN node, and the core network node in order to update their functionalities.

The above example aspects are also applicable to 'non-mobile' or generally stationary user equipment.

Various other modifications will be apparent to those skilled in the art and will not be described in further detail here.

Claim 1:
A Network Function node for network slice quota, comprising:
means for managing a number of user equipment (<NUM>), UE, registered in a network slice;
means for receiving a first request, from a core network node in a core network (<NUM>), for checking availability of the network slice, including information indicating the network slice;
means for checking the availability of the network slice in accordance with the number of UE (<NUM>) registered in the network slice; and
means for sending, to the core network node, a first response to the first request, indicating the availability,
wherein the first response causes the core network node to reject a registration procedure for UE (<NUM>) based on the number of UE registered in the network slice,
wherein, the core network node is included in a visited Public Land Mobile Network, PLMN,
wherein the means for receiving are configured to receive an update flag, from the core network node, indicating that the number of UE (<NUM>) registered in the network slice is to be decreased, and
wherein the Network Function node further comprising means for decreasing the number of UE (<NUM>) registered in the network slice based on the update flag.