Method of conveying network function's event capabilities to network function repositories / subscriber repositories

Abstract

NOT VISIBLE DUE TO STATUS OF PATENT

Description

METHOD OF CONVEYING NETWORK FUNCTION'S EVENT CAPABILITIES TO NETWORK FUNCTION REPOSITORIES / SUBSCRIBER REPOSITORIESRelated Applications

[0001] This application claims the benefit of provisional patent application serial number 63 / 548,908, filed February 2, 2024, as well as provisional patent application serial number 63 / 625,302 filed January 26, 2024, the disclosures of which are hereby incorporated herein by reference in their entireties.Technical Field

[0002] The present disclosure relates to methods and network nodes that can receive, retrieve, and store network function event capabilities to network repositories in a wireless communication system.Background

[0003] In service-based architecture, network function service providers register their supported services in a Network Repository Function. Network function service consumers use the registration information to discover services supported by various network function service producers in the network. In an Internet Protocol (IP) Multimedia Subsystem (IMS) (e.g. TS 23.228) a repository exists for providing subscriber related functionality (e.g. user profiles, subscription data, etc.) and the services they have subscribed to.

[0004] Examples of the repository functions in the Third Generation Partnership Program (3GPP) service-based architecture are:• Unified Data Management (UDM) / Home Subscriber Server (HSS) where the network function provides the instance which serves a certain User Equipment (UE) or a registered subscriber.• Network Repository Function (NRF) where network function service providers register their supported services and capabilities so other network function service consumers can discover and select those services.

[0005] Network function service providers can support subscriptions to expose relevant events to interested consumers. When subscribed events are detected,notifications including relevant event data are sent to subscribed consumers. Such events are often in the context of a UE or in the context of an IMS subscriber.

[0006] A network function service consumer interested in an event sends a request to subscribe to the event. The request includes an event identification and a UE or subscriber identification. A network function service consumer may be interested in an event which is not related to a UE or IMS subscriber. In that case, the request contains an event identification but not UE or subscriber identification.

[0007] Currently in Fifth Generation Core network (5GC), a network function consumer subscribes to the event of interest directly with the Network function producer supporting such an event or via UDM acting as registrar of the Network Function (NF) instance which serves a certain UE. A network function repository receiving such a subscription request needs to:• Find the network function type providing the event identified in the request.• Find the network function provider node instance which serves the UE or subscriber identified in the request.

[0008] The network function type identification is based on the event ID. The network function supporting such an event is known to the consumer due to predetermined assignment of network functions to event identities (see table 4.15.3.1-1 in TS 23.502). For example: Loss of connectivity event is provided by Access and Mobility Management Function (AMF) in a 5G core network.

[0009] The network function service provider node instance which serves the UE or subscriber identified in the subscription request is determined by using prior registration of bindings of UE-s and / or subscriber identities to node instances addresses. This is, in 5GC Exposure Framework defined in 3GPP TS 23.501 and TS 23.502, determined based on the registration of network functions in UDM (e.g. AMF, SMF) for a specific subscriber.Summary

[0010] Various embodiments disclosed herein provide methods for receiving, retrieving, and storing network function event capabilities to network repositories in a wireless communication system. In an embodiment, a registrar function, either a Home Subscriber Server (HSS) or Network Repository Function (NRF), can receive, from a Network Function (NF), a registration request comprising node event capabilityinformation associated with the NF server function. The registrar function can then store the node event capability in a tuple. Then, when a subscription request from a network function service consumer containing an event identification and a subscriber identification is initiated, the network function service consumer or the network function subscriber repository can identify the NF server node instance to configure the event of interest using the node event capability provided to the subscriber repository or to the network function repository.

[0011] In an embodiment, a method of registering network function event capabilities performed by an NRF is provided where the method includes receiving, by the NRF from an NF, a registration request comprising an instance identifier associated with the NF and node event capability information associated with the NF, wherein the node event capability information identifies event identifiers supported by the NF. The method also includes storing, by the NRF, the node event capability information.

[0012] In an embodiment, the registration request comprises node profile information comprising the node event capability information.

[0013] In an embodiment, the node event capability information is stored as a tuple.

[0014] In an embodiment, the node event capability information and tuple are stored by the NRF within the node profile information.

[0015] In an embodiment, the method further includes receiving, from a Home Subscriber Server (HSS), a node profile information request comprising the instance identifier associated with the NF and providing, to the HSS, the node event capability information associated with the NF within the node profile information.

[0016] In an embodiment, the method further includes receiving, from a consumer node, a node profile information request comprising an NF type associated with the NF and providing, to the consumer node via the NRF, the node event capability information associated with the NF within the node profile information.

[0017] In an embodiment, the NF comprises an Internet Protocol (IP) Multimedia Subsystem (IMS) Application Server (IMS AS).

[0018] In an embodiment, a network node configured to implement an NRF is provided, where the network node includes a network interface configured to communicate with other network nodes and processing circuitry configured to receive, by the NRF from an NF, a registration request comprising an instance identifier associated with the NF and node event capability information associated with the NF,wherein the node event capability information identifies event identifiers supported by the NF; and store by the NRF, the node event capability information.

[0019] A method of registering network function event capabilities performed by an NF is provided where the method includes providing to an NRF a registration request comprising an instance identifier associated with the NF and node event capability information associated with the NF, wherein the node event capability information identifies event identifiers supported by the NF. In an embodiment, the NF comprises an IMS AS.

[0020] In an embodiment, a network node configured to implement an NF is provided where the network node includes a network interface configured to communicate with other network nodes, and processing circuitry configured to provide to an NRF a registration request comprising an instance identifier associated with the NF and node event capability information associated with the NF, wherein the node event capability information identifies event identifiers supported by the NF.

[0021] A method to retrieve network function event capabilities performed by an HSS is provided where the method includes providing, to an NRF serving as a registrar function, a node profile information request comprising an instance identifier associated with an NF and receiving, from the NRF, node event capability information associated with the NF, wherein the node event capability information identifies event identifiers supported by the NF. In an embodiment, the NF comprises an IMS AS. In an embodiment, the method also includes providing, to the NF, a subscription request based on the node event capability information associated with the NF.

[0022] In an embodiment, a network node configured to implement an HSS is provided where the network node includes a network interface configured to communicate with other network nodes, and processing circuitry configured to provide, to an NRF serving as a registrar function, a node profile information request comprising an instance identifier associated with an NF and receive, from the NRF, node event capability information associated with the NF, wherein the node event capability information identifies event identifiers supported by the NF.

[0023] In an embodiment, a method to retrieve network function event capabilities of an NF performed by a consumer node is provided, where the method includes providing, to an NRF, a node profile information request comprising an NF type associated with the NF; and receiving, from the NRF, the node event capabilityinformation associated with the NF within the node profile information. In an embodiment, the method also includes providing, to the NF, a subscription request based on the node event capability information associated with the NF.

[0024] In an embodiment, a network node configured to implement a consumer node for retrieving network function event capabilities of an NF is provided, where the network node includes a network interface configured to communicate with other network nodes, and processing circuitry configured to provide, to an NRF, a node profile information request comprising an NF type associated with the NF; and receive, from the NRF, the node event capability information associated with the NF.

[0025] Computer-readable mediums are also provided that store computerexecutable instructions that, when executed by a processor, cause the processor to implement a method according to any of the embodiments above.Brief Description of the Drawings

[0026] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.

[0027] Figure 1 illustrates a message sequence chart for a method of registration with a home subscriber service (HSS) as a network registrar function according to one or more embodiments of the present disclosure;

[0028] Figure 2 illustrates a message sequence chart for a method of subscription via HSS signaling flow according to one or more embodiments of the present disclosure;

[0029] Figure 3 illustrates a message sequence chart for a method of direct subscription signaling flow according to one or more embodiments of the present disclosure;

[0030] Figure 4 illustrates a message sequence chart for a method of registration with a network repository function (NRF) as a network registrar function according to one or more embodiments of the present disclosure;

[0031] Figure 5 illustrates a message sequence chart for a method of subscription via HSS signaling flow with the NRF as a registrar according to one or more embodiments of the present disclosure;

[0032] Figure 6 illustrates a message sequence chart for a method of direct subscription signaling flow with the NRF as a registrar according to one or more embodiments of the present disclosure;

[0033] Figure 7 illustrates a wireless communication system represented as a Fifth Generation (5G) network architecture composed of core Network Functions (NFs);

[0034] Figure 8 illustrates a 5G network architecture using service-based interfaces between the NFs in the Control Plane (CP);

[0035] Figure 9 is a schematic block diagram of a network node according to some embodiments of the present disclosure;

[0036] Figure 10 is a schematic block diagram that illustrates a virtualized embodiment of the network node according to some embodiments of the present disclosure; and

[0037] Figure 11 is a schematic block diagram of the network node according to some other embodiments of the present disclosure.Detailed Description

[0038] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject matter disclosed herein, the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.Network Node: As used herein, a "network node" is any type of node in a core network or any node that implements a core network function. Some examples of a core network node include, e.g., a Mobility Management Entity (MME), a Packet Data Network Gateway (P-GW), a Service Capability Exposure Function (SCEF), a Home Subscriber Server (HSS), or the like. Some other examples of a core network node include a node implementing a Home Subscriber Server (HSS) or Network Repository Function (NRF), Internet Protocol (IP) Multimedia Subsystem (IMS) Application Server (AS) network function, Access and Mobility Management Function (AMF), a User Plane Function (UPF), a Session Management Function (SMF), an Authentication Server Function (AUSF), a Network Slice Selection Function (NSSF), a Network ExposureFunction (NEF), a Network Function (NF) Repository Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), or the like.

[0039] Note that the description given herein focuses on a Third Generation Partnership Program (3GPP) cellular communications system and, as such, 3GPP terminology or terminology similar to 3GPP terminology is oftentimes used. However, the concepts disclosed herein are not limited to a 3GPP system.

[0040] There currently exist certain challenge(s).

[0041] The registration of an IMS AS instance serving a registered IMS subscriber in HSS could make use of the Network Function (NF) Type for "IMS_AS" already defined in TS 29.510. However, the IMS AS network function represents multiple types of application servers (for example Multimedia Telephony AS, Service Continuity AS, and others). Multiple IMS AS functions are providing services for the same IMS subscriber simultaneously (AS chaining concept). It is also understood that different IMS AS types will be capable of reporting different types of IMS exposure events.

[0042] When a request from a network function service consumer containing an event identification and an IMS subscriber identification needs to be initiated, the network function consumer can determine the network function provider node instance which serves the IMS subscriber identified in the request using the HSS as an event registrar of such information.

[0043] Since multiple IMS AS network function node instances can serve the same IMS subscriber the network service consumer or the event registrar do not know to which IMS AS node instance to forward the request which can accept the subscription for the requested event, since the IMS AS registration information in HSS does not include information regarding the type of IMS AS (e.g. is it an MMTel AS, SCO AS etc.).

[0044] In short, the objective in the disclosure is that for IMS exposure events, such a pre-determined assignment between a network function and the events supported by it can be dynamically discovered, as opposed to be pre-determined and known to the service consumer. Additionally, there is a need to discover the specific node instance serving the IMS subscriber being the subject of the requested event.

[0045] Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned or other challenges.

[0046] Various embodiments disclosed herein provide methods for receiving, retrieving, and storing network function event capabilities to network repositories in awireless communication system. In an embodiment, a registrar function (either a HSS or NRF, can receive, from an IMS AS function, a registration request comprising node event capability information associated with the IMS AS function. The registrar function can then store the node even capability in a tuple. Then, when a subscription request from a network function service consumer containing an event identification and an IMS subscriber identification is initiated, the network function service consumer or the network function subscriber repository can identify the IMS AS node instance to configure the event of interest using the node event capability provided to the subscriber repository or to the network function repository.

[0047] Currently, when a network function registers with a repository it provides either:• a binding between a node instance and the served IMS subscriber (i.e. in the case of HSS).• a binding between a node instance and the supported services and other node capabilities (i.e. in the case of NRF).

[0048] Currently in the Fifth Generation Core network (5GC), when a network function service provider registers with the repository function (i.e., in the case of NRF) a binding between a node instance and the supported services and other node capabilities is provided.

[0049] In IMS (i.e., in the case of HSS) a binding between a node instance and the served IMS subscriber is stored.

[0050] To identify an IMS subscriber an IMS Public User Identity (IMPU) is used. When a bounding is created between an IMS Subscriber and a node instance all the IMPU-s in the Implicit Registration Set (IRS) are bound to the node instance.

[0051] The proposed solution is to provide additional information to the network function event registrar / repository for both of the above options so that as part of this binding, the IMS AS provides information about supported events by the node instance type as well, which represents the node capability information. This additional information will be referred to as node event capability information in the rest of this document. An example of this additional information I node event capability information is; "Telephony_Events" (may be registered by an AS supporting telephony, e.g. MMTel), "Continuity_Events" (may be registered by an AS supporting call continuity, e.g. SCO AS) etc.

[0052] When a subscription request from a network function service consumer containing an event identification and an IMS subscriber identification is initiated, the network function service consumer or the network function subscriber repository can identify the IMS AS node instance to configure the event of interest using the node event capability provided to the subscriber repository or to the network function repository.

[0053] The subscriber identification in the subscription request can be any IMPU from the implicit registration set.

[0054] For example, if two IMS AS (as per NF Type: "IMS_AS" as defined in TS 29.510) node instances are serving the same IMS subscriber, one Multimedia Telephony AS and one Service Continuity AS, and the requested event is for Telephony events then the event registrar chooses the Multimedia Telephony AS node instance from the bindings which contained the Telephony event.

[0055] Certain embodiments may provide one or more of the following technical advantage(s). The advantage of the solution is that it is possible to determine the correct node instance ID for an exposure event monitoring request serving a specific IMS subscriber in a dynamic way without having to specify the association of a given IMS event to a given type of IMS AS and thus be dependent on 3GPP standardization cycles (improving Time To Market etc.).

[0056] While the solution enables de-coupling from the 3GPP standardization cycles it also provides an extensible framework that ensures multi-vendor interoperability. It can if required be extended to provide support for more granular exposure events related to the defined event categories.

[0057] The dynamicity of the solution will also prevent the risk of fragmentation whereby multiple exposure events from multiple NFs (AS types) requiring multiple standardization cycles need to be defined. This in turn may lead to capacity concerns whereby similar events related to the same subscriber is subscribed to and notified from multiple NFs.

[0058] It is also an advantage that when an IMS subscriber is served by many different IMS AS nodes with different event exposure capabilities it is possible to select a single node instance using the event identification from the request and matching it to the registered node event capability, so that the request does not need to be forked to all IMS AS nodes.

[0059] The present disclosure proposes different options for the IMS AS to provide the new node event capability information by the IMS AS node instance.

[0060] At the time IMS AS assigned to an IMS subscriber (either during a 3rd party IMS Registration or session handling for unregistered subscriber) the new node event capability information is provided to HSS acting as subscriber repository.

[0061] At the time of Registration of the IMS AS NF profile in NRF, using NRF as registrar of the new node event capability information.

[0062] Depending on the option, different alternatives exist to retrieve the information and use it to determine the IMS AS node instance supporting a requested IMS event by a consumer.

[0063] Figure 1 illustrates a message sequence chart for a method of registration with a home subscriber service (HSS) as a network registrar function according to one or more embodiments of the present disclosure. It is to be appreciated that in Figure 1, and the subsequent figures, optional steps are drawn with broken lines, while non- optional steps are depicted with solid lines.

[0064] The method can begin at step 110 where the UE 108 registers with an IMS 106. As part of the registration process, the IMS 106 sends a registration (e.g., 3rdparty) message to IMS AS 104 at step 112, and the receives a 200 OK response at step 114. It is to be appreciated that while network node 104 is depicted as an IMS AS, in other embodiments, the network node 104 could be any appropriate or relevant network function (NF) 104 such as a Serving Call Session Control Function (S-CSCF).

[0065] At step 116, the IMS AS 104 executes a registration procedure with the network registrar function (i.e. HSS 102) in the context of the 3rdparty IMS registration. The registration request to the network registrar function / HSS 102 contains the served subscriber identity and the instance identity of the serving IMS AS 104. Additionally, the registration request can also include the new node event capability information. The HSS 102 then becomes the event registrar of this NEW node event capability information. In addition, the IMS AS 104 may also execute this registration procedure whenever it is handling a session for a given subscriber (e.g. session handling for unregistered subscribers).

[0066] At step 118, the HSS 102 stores the served subscriber identity, the instance ID, and the node event capability information as a tuple. When the HSS 102 laterreceives an Event ID and a subscriber ID, the HSS 102 can then determine the corresponding instance ID of the IMS AS 104 instance associated with the event.

[0067] Figure 2 illustrates a message sequence chart for a method of subscription via HSS signaling flow according to one or more embodiments of the present disclosure;

[0068] Later on, the consumer 202 interested in subscribing for event notification (for example: User Call State) from a service producer issues a subscription request at step 204 which contains amongst other information the identification of the requested event and the identification of the subscriber in context of the requested event notification is applicable.

[0069] In one alternative of this embodiment, the subscribe request is received eventually by the HSS 102 also acting as registrar of the NEW node event capability information. Other nodes (e.g. NEF) may also be involved before the HSS 102 receives the request. The registrar identifies, at step 206, the requested network function type and the serving node instance identity using the tuple of [Supported Event ID(s), Subscriber ID, Instance ID] saved during registration at step 118 in Figure 1.

[0070] The registrar (HSS) then subscribes at step 208 to the event in the corresponding IMS AS 104 instance supporting the requested event on behalf of the service Consumer 202. At step 210, the HSS 102 receives the response from the IMS AS 104, and then the HSS 102 responds with confirmation to the subscription to the consumer 202 at step 212. The response at 212 includes identifiers for registered IMS AS (104) instances and node event capability information for each IMS AS instance 104.

[0071] Figure 3 illustrates a message sequence chart for a method of direct subscription signaling flow according to one or more embodiments of the present disclosure.

[0072] In the embodiment in Figure 1, as in the previous Figure 1, the tuple comprising the node event capability information, subscriber ID, and instance ID of the associated IMS AS 104 instance is stored at the HSS 102 in step 118.

[0073] A consumer 202 can then find which IMS AS 104 instances registered for a given IMS user issuing a NEW request to the HSS 102. For this, the present disclosure proposes a NEW Nhss_imsUECM_GET service operation supported by the HSS 102. This service operation, referred to herein as a "IMS UE Request" is provided by the consumer 202 to the HSS 102 at step 302, and at step 304, the HSS 102 includes in theresponse each registered IMS AS 104 instance and for each registered IMS AS 104 instance IDs the node event capabilities previously registered in HSS by the IMS AS 104.

[0074] This allows the consumer 202 to determine at step 306 if any of the registered IMS AS 104 instances support the requested event type and if so, the consumer subscribes to the event directly at step 308 in the corresponding IMS AS 104 instance. The IMS AS 104 can then respond at step 310 with a subscription response message.

[0075] Figure 4 illustrates a message sequence chart for a method of registration with a network repository function (NRF) as a network registrar function according to one or more embodiments of the present disclosure.

[0076] In an alternative embodiment to that depicted in Figure 1, instead of an HSS 102 acting as the registrar function, in the embodiment in Figure 4, an NRF 402 can act as the registrar function.

[0077] This embodiment of the present disclosure proposes that at the time of NF profile registration of the IMS AS 104 in the NRF 402, the IMS AS 104 includes in its Network Function (NF) profile the events supported by the IMS AS 104 as NEW node event capability information. The NRF 402 then becomes the event registrar of this NEW node event capability information when the NRF 402 receives the instance ID of the IMS AS 104 and the NF profile including the node event capability information from the IMS AS 104 at step 404. At step 406, the NRF 402 can then store the tuple comprising the instance ID and NF profile in the NRF 402. The NRF 402 can then send a registration response at step 408 to the IMS AS 104.

[0078] The IMS user will then register in IMS as per steps 410, 412, 414, 416, and 418. For example, at step 410 the UE 108 performs IMS registration with the IMS 106, at step 412, the IMS 106 sends the IMS AS 104 a register request, and receives back a 200 OK message at step 414. At step 416, the IMS AS 104 sends a registration message to the HSS 102, but just includes the instance ID and the subscriber ID and does not include the node event capability information, since this was already shared with the NRF 402.

[0079] Figure 5 illustrates a message sequence chart for a method of subscription via HSS signaling flow with the NRF as a registrar according to one or more embodiments of the present disclosure.

[0080] As described above, at step 406, the NRF 402 stores a tuple with the instance ID and node event capability information, while the HSS 102 stores a tuple comprising the instance ID and the subscriber ID at step 502.

[0081] Later on, the consumer 202 may be interested in subscribing for event notification from a service producer and can issue a subscription request at step 504 which contains amongst other information the identification of the requested event and the identification of the subscriber in context of the requested event. The consumer subscription request is received eventually by the HSS 102. Other nodes (e.g. NEF) may also be involved before the subscriber repository function (HSS 102) receives the request. In this case the HSS 102 acts as subscriber repository function containing the binding of the Subscriber ID with the IMS AS instance ID, while the NRF 402 contains the binding between the IMS AS Instance ID type and the node event capability information for each IMS AS 104 instance. Therefore, the HSS 102 retrieves the NF profiles of the registered IMS AS instance types for the user in a discovery request at step 506 that includes the instance ID. The NF profiles returned by the NRF 402 will include the node event capability information at step 508.

[0082] Then the HSS 102 can determine which of the registered IMS AS instances support the requested event and then proceeds to subscribe at step 510 to the event in the corresponding IMS AS 104 instance supporting the requested event on behalf of the Consumer 202. The IMS AS 104 can provide a response at step 512, and then the HSS 102 can respond to the consumer 202 with the subscription response at step 514.

[0083] Figure 6 illustrates a message sequence chart for a method of direct subscription signaling flow with the NRF as a registrar according to one or more embodiments of the present disclosure.

[0084] As described above, at step 406, the NRF 402 stores a tuple with the instance ID and node event capability information, while the HSS 102 stores a tuple comprising the instance ID and the subscriber ID at step 502.

[0085] In another alternative of this embodiment, the consumer 202 first finds out the IMS AS instances type registered for the given IMS user issuing a NEW request to the HSS 102 at steps 602 and 604. The same NEW Nhss_imsUECM_GET service operation as proposed in Figure 2 can be used, except that the response would not include information about the Supported Event types as in this option, the registrar forthis information is the NRF 402 instead. The response includes the IMS AS 104 registered instances.

[0086] For determining whether any of the registered IMS AS instances support the requested event type, the consumer 202 then retrieves their NF profiles from the NRF 402 at step 606. The NF profiles returned by the NRF 402 at step 608 will include the node event capability information.

[0087] Then, the Consumer 202 can determine which of the registered IMS AS 104 instances support the requested event and then proceeds to subscribe to the event in the corresponding IMS AS instance supporting the requested event at step 610 and 612.

[0088] The same concept of registering the supported event types in a registrar (HSS or NRF) instead of pre-defining the event type to a given NF type, may be applied as well to the existing Exposure Framework in 5GC.

[0089] In this case, 5GC NFs may include the list of supported events in the 5GC when they register in UDM or in the NRF and consumers within the 5GC may be able to determine the target NF type within the 5GC responsible for each event via the registrar (UDM or NRF).

[0090] The same concept of registering node event capabilities can be applied to all NF types in the IMS domain not just IMS AS (e.g. CSCF). Therefore, some embodiments described herein might not involve an IMS AS, but rather might more generally involve an NF which may or may not be an IMS AS because other NF types are possible.

[0091] The same concept of registering node event capabilities can be applied to events which are not related to a single subscriber or UE. For example, reporting network level counters.

[0092] As used herein, a "consumer" or a "consumer device" can include any apparatus in a role of "consuming" a service provided by a network node providing the service. Such apparatus can include a consumer product such as a mobile phone for example. However, the apparatus can instead include other products such as a network node for example.

[0093] Figure 7 illustrates a wireless communication system represented as a 5G network architecture composed of core Network Functions (NFs), where interaction between any two NFs is represented by a point-to-point reference point / interface.

[0094] Seen from the access side the 5G network architecture shown in Figure 7 comprises a plurality of UEs 108 connected to either a RAN or an Access Network (AN) as well as an AMF 700. Typically, the R(AN) comprises base stations, e.g. such as eNBs or gNBs or similar. Seen from the core network side, the 5GC NFs shown in Figure 7 include a NSSF 702, an AUSF 704, a UDM 706, the AMF 700, a SMF 708, a PCF 710, and an Application Function (AF) 712.

[0095] Reference point representations of the 5G network architecture are used to develop detailed call flows in the normative standardization. The N1 reference point is defined to carry signaling between the UE 108 and AMF 700. The reference points for connecting between the AN and AMF 700 and between an Access Network (AN) and UPF 714 are defined as N2 and N3, respectively. There is a reference point, Nil, between the AMF 700 and SMF 708, which implies that the SMF 708 is at least partly controlled by the AMF 700. N4 is used by the SMF 708 and UPF 714 so that the UPF 714 can be set using the control signal generated by the SMF 708, and the UPF 714 can report its state to the SMF 708. N9 is the reference point for the connection between different UPFs 714, and N14 is the reference point connecting between different AMFs 700, respectively. N15 and N7 are defined since the PCF 710 applies policy to the AMF 700 and SMF 708, respectively. N12 is required for the AMF 700 to perform authentication of the UE 108. N8 and N10 are defined because the subscription data of the UE 108 is required for the AMF 700 and SMF 708.

[0096] The 5GC network aims at separating UP and CP. The UP carries user traffic while the CP carries signaling in the network. In Figure 7, the UPF 714 is in the UP and all other NFs, i.e., the AMF 700, SMF 708, PCF 710, AF 712, NSSF 702, AUSF 704, and UDM 706, are in the CP. Separating the UP and CP guarantees each plane resource to be scaled independently. It also allows UPFs to be deployed separately from CP functions in a distributed fashion. In this architecture, UPFs may be deployed very close to UEs to shorten the Round Trip Time (RTT) between UEs and data network for some applications requiring low latency.

[0097] The core 5G network architecture is composed of modularized functions. For example, the AMF 700 and SMF 708 are independent functions in the CP. Separated AMF 700 and SMF 708 allow independent evolution and scaling. Other CP functions like the PCF 710 and AUSF 704 can be separated as shown in Figure 7. Modularized function design enables the 5GC network to support various services flexibly.

[0098] Each NF interacts with another NF directly. It is possible to use intermediate functions to route messages from one NF to another NF. In the CP, a set of interactions between two NFs is defined as service so that its reuse is possible. This service enables support for modularity. The UP supports interactions such as forwarding operations between different UPFs.

[0099] Figure 8 illustrates a 5G network architecture using service-based interfaces between the NFs in the CP, instead of the point-to-point reference points / interfaces used in the 5G network architecture of Figure 7. However, the NFs described above with reference to Figure 7 correspond to the NFs shown in Figure 8. The service(s) etc. that an NF provides to other authorized NFs can be exposed to the authorized NFs through the service-based interface. In Figure 8 the service based interfaces are indicated by the letter "N" followed by the name of the NF, e.g. Namf for the service based interface of the AMF 700 and Nsmf for the service based interface of the SMF 708, etc. The NEF 800 and the NRF 802 in Figure 8 are not shown in Figure 7 discussed above. However, it should be clarified that all NFs depicted in Figure 7 can interact with the NEF 800 and the NRF 802 of Figure 8 as necessary, though not explicitly indicated in Figure 7.

[0100] Some properties of the NFs shown in Figures 7 and 8 may be described in the following manner. The AMF 700 provides UE-based authentication, authorization, mobility management, etc. A UE 108 even using multiple access technologies is basically connected to a single AMF 700 because the AMF 700 is independent of the access technologies. The SMF 708 is responsible for session management and allocates Internet Protocol (IP) addresses to UEs. It also selects and controls the UPF 714 for data transfer. If a UE 108 has multiple sessions, different SMFs 708 may be allocated to each session to manage them individually and possibly provide different functionalities per session. The AF 712 provides information on the packet flow to the PCF 710 responsible for policy control in order to support QoS. Based on the information, the PCF 710 determines policies about mobility and session management to make the AMF 700 and SMF 708 operate properly. The AUSF 704 supports authentication function for UEs or similar and thus stores data for authentication of UEs or similar while the UDM 706 stores subscription data of the UE 108. The Data Network (DN), not part of the 5GC network, provides Internet access or operator services and similar.

[0101] An NF may 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., a cloud infrastructure.

[0102] Figure 9 is a schematic block diagram of a network node 900 according to some embodiments of the present disclosure. Optional features are represented by dashed boxes. The network node 900 may be, for example, a network node that implements all or part of the functionality of the IMS AS 104, HSS 102, or NRF 402 described herein. As illustrated, the network node 900 includes a control system 902 that includes one or more processors 904 (e.g., Central Processing Units (CPUs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), and / or the like), memory 906, and a network interface 908. The one or more processors 904 are also referred to herein as processing circuitry. The one or more processors 904 operate to provide one or more functions of the network node 900 as described herein. In some embodiments, the function(s) are implemented in software that is stored, e.g., in the memory 906 and executed by the one or more processors 904.

[0103] Figure 10 is a schematic block diagram that illustrates a virtualized embodiment of the network node 900 according to some embodiments of the present disclosure. Again, optional features are represented by dashed boxes. As used herein, a "virtualized" network node is an implementation of the network node 900 in which at least a portion of the functionality of the network node 900 is implemented as a virtual component(s) (e.g., via a virtual machine(s) executing on a physical processing node(s) in a network(s)). The network node 900 includes one or more processing nodes 1000 coupled to or included as part of a networks) 1002. Each processing node 1000 includes one or more processors 1004 (e.g., CPUs, ASICs, FPGAs, and / or the like), memory 1006, and a network interface 1008.

[0104] In this example, IMS AS 104, HSS 102, or NRF 402 of the network node 900 described herein are implemented at the one or more processing nodes 1000 or distributed across the one or more processing nodes 1000 and the control system 902 in any desired manner. In some particular embodiments, some or all of the functions 1010 of the network node 900 described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environment s) hosted by the processing node(s) 1000. As will be appreciated by one of ordinary skillin the art, additional signaling or communication between the processing node(s) 1000 and the control system 902 is used in order to carry out at least some of the desired functions 1010.

[0105] In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of the network node 900 or a node (e.g., a processing node 1000) implementing one or more of the functions 1010 of the network node 900 in a virtual environment according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

[0106] Figure 11 is a schematic block diagram of the network node 900 according to some other embodiments of the present disclosure. The network node 900 includes one or more of IMS AS 104, HSS 102, or NRF 402, each of which is implemented in software. The module(s) 1100 provides the functionality of the network node 900 described herein. This discussion is equally applicable to the processing node 1000 of Figure 10 where the modules 1100 may be implemented at one of the processing nodes 1000 or distributed across multiple processing nodes 1000 and / or distributed across the processing node(s) 1000 and the control system 902.

[0107] Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include Digital Signal Processor (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and / or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitrymay be used to cause the respective functional unit to perform corresponding functions according to one or more embodiments of the present disclosure.

[0108] While processes in the figures may show a particular order of operations performed by certain embodiments of the present disclosure, it should be understood that such order is exemplary (e.g., alternative embodiments may perform the operations in a different order, combine certain operations, overlap certain operations, etc.).

[0109] Some of the embodiments of the present disclosure include

[0110] Embodiment 1: A method of registering network function event capabilities performed by a registrar function (102, 402), the method comprising: receiving (116, 404), by the registrar function (102, 402), from a Network Function, NF, (104) a registration request comprising node event capability information associated with the NF (104); and storing (118, 406), by the registrar function (102, 402), the node event capability information in a tuple.

[0111] Embodiment 2: The method of embodiment 1, wherein the registrar function (102, 402) is a Home Subscriber Server, HSS, (102).

[0112] Embodiment 3: The method of embodiment 2, wherein the tuple also comprises an instance identifier associated with the NF (104) and subscriber information associated with a subscriber identity.

[0113] Embodiment 4: The method of embodiment 1, wherein the registrar function (102, 402) is a Network Repository Function, NRF, (402).

[0114] Embodiment 5: The method of embodiment 4, wherein the tuple also comprises an instance identifier associated with the NF (104).

[0115] Embodiment 6: The method of any of embodiments 4 to 5, wherein the registration request comprises node profile information comprising the node event capability information.

[0116] Embodiment 7: The method of embodiment 3, further comprising: receiving (204) a subscription request comprising an event identifier and subscriber information identifying (206) an NF (104) instance based on the subscription request and the tuple; and subscribing (208) to an event at the NF (104) instance.

[0117] Embodiment 8: The method of embodiment 3, further comprising: receiving (302) a user request comprising subscriber information; providing (304) identifiers forregistered NF (104) instances and node event capability information for each NF (104) instance.

[0118] Embodiment 9: The method of embodiment 5, further comprising: receiving (506), from a Home Subscriber Server, HSS, (102) a node profile information request comprising an instance identifier associated with the NF (104); providing (508), to the HSS (102), node event capability information associated with the NF (104).

[0119] Embodiment 10: The method of embodiment 5, further comprising: receiving (606), from a consumer device (202), a node profile information request comprising an instance identifier associated with the NF (104); providing (608), to the consumer device (202) via the registrar function (102, 402), node event capability information associated with the NF (104).

[0120] Embodiment 11: The method of any of embodiments 1 to 10, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

[0121] Embodiment 12: A network node (900) configured to implement a registrar function (102, 402) that registering network function event capabilities, the network node (900) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: receive (116, 404), by the registrar function (102, 402), from a Network Function, NF, (104) a registration request comprising node event capability information associated with the NF (104); and store (118, 406), by the registrar function (102, 402), the node event capability information in a tuple

[0122] Embodiment 13: The network node (900) of embodiment 12, wherein the processing circuitry is further configured to perform the methods of embodiments 2 to 11.

[0123] Embodiment 14: A computer-readable medium that stores computerexecutable instructions, that when executed by a processor, cause the processor to implement a method according to any one of embodiments 1 to 11.

[0124] Embodiment 15: A method of registering network function event capabilities performed by a Network Function, NF, (104) the method comprising: providing (116, 404), to a registrar function, a registration request comprising node event capability information associated with the NF (104).

[0125] Embodiment 16: The method of embodiment 15, wherein the registrar function (102, 402) is one of a Home Subscriber Server, HSS, (102) or a Network Repository Function, NRF (402).

[0126] Embodiment 17: The method of any of embodiments 15 to 16, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

[0127] Embodiment 18: A network node (900) configured to implement a Network Function, NF, (104) for registering network function event capabilities, the network node (900) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: provide (116, 404), to a registrar function (102, 402), a registration request comprising node event capability information associated with the NF (104).

[0128] Embodiment 19: The network node (900) of embodiment 16, wherein the processing circuitry is further configured to perform the method of any one of embodiments 15 to 17.

[0129] Embodiment 20: A computer-readable medium that stores computerexecutable instructions, that when executed by a processor, cause the processor to implement a method according to any one of embodiments 15 to 17.

[0130] Embodiment 21: A method to retrieve network function event capabilities performed by a consumer device (202), the method comprising: providing (204, 302), to a Home Subscriber Server, HSS, (102) a request comprising subscriber information; receiving (212, 304), from the HSS (102), identifiers for registered NF (104) instances and node event capability information for each NF (104) instance.

[0131] Embodiment 22: The method of embodiment 21, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

[0132] Embodiment 23: A consumer device (202) configured to retrieve network function event capabilities, the consumer device (202) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: provide (204, 302), to a Home Subscriber Server, HSS, (102) a request comprising subscriber information; receive (212, 304), from the HSS (102), identifiers for registered NF (104) instances and node event capability information for each NF (104) instance.

[0133] Embodiment 24: A computer-readable medium that stores computerexecutable instructions, that when executed by a processor, cause the processor to implement a method according to any one of embodiments 21 to 22.

[0134] Embodiment 25: A method to retrieve network function event capabilities performed by a Home Subscriber Server, HSS, (102) the method comprising: providing (506), to Network Repository Function, NRF, (402) serving as a registrar function (102, 402), a node profile information request comprising an instance identifier associated with a Network Function, NF, (104); receiving (508), from the NRF (402), node event capability information associated with the NF (104).

[0135] Embodiment 26: The method of embodiment 25, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

[0136] Embodiment 27: A network node (900) configured to implement a Home Subscriber Server, HSS, (102) for retrieving network function event capabilities, the network node (900) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: provide (506), to Network Repository Function, NRF, (402) serving as a registrar function (102, 402), a node profile information request comprising an instance identifier associated with a Network Function, NF, (104); receive (508), from the NRF (402), node event capability information associated with the NF (104).

[0137] Embodiment 28: The network node (900) of embodiment 25, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

[0138] Embodiment 29: A computer-readable medium that stores computerexecutable instructions, that when executed by a processor, cause the processor to implement a method according to any one of embodiments 27 to 28.

Claims

ClaimsWhat is claimed is:

1. A method of registering network function event capabilities performed by a Network Repository Function, NRF, (402), the method comprising: receiving (404), by the NRF (402) from a Network Function, NF, (104), a registration request comprising an instance identifier associated with the NF (104) and node event capability information associated with the NF (104), wherein the node event capability information identifies event identifiers supported by the NF (104); and storing (406), by the NRF (402), the node event capability information.

2. The method of claim 1, wherein the registration request comprises node profile information comprising the node event capability information.

3. The method of any of claims 1 to 2, wherein the node event capability information is stored as a tuple.

4. The method of claim 3, wherein the node event capability information and tuple are stored by the NRF (402) within the node profile information.

5. The method of any of claims 1 to 4, further comprising: receiving (506), from a Home Subscriber Server, HSS, (102) a node profile information request comprising the instance identifier associated with the NF (104); and providing (508), to the HSS (102), the node event capability information associated with the NF (104) within the node profile information.

6. The method of any of claims 1 to 5, further comprising: receiving (606), from a consumer node (202), a node profile information request comprising an NF type associated with the NF (104); and providing (608), to the consumer node (202) via the NRF (402), the node event capability information associated with the NF (104) within the node profile information.

7. The method of any of claims 1 to 6, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

8. A network node (900) configured to implement a Network Repository Function, NRF, (402) for registering network function event capabilities, the network node (900) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: receive (404), by the NRF (402) from a Network Function, NF, (104), a registration request comprising an instance identifier associated with the NF (104) and node event capability information associated with the NF (104), wherein the node event capability information identifies event identifiers supported by the NF (104); and store (406), by the NRF (402), the node event capability information.

9. The network node (900) of claim 8, wherein the registration request comprises node profile information comprising the node event capability information.

10. The network node (900) of any of claims 8 to 9, wherein the node event capability information is stored as a tuple.

11. The network node of claim 10, wherein the node event capability information and tuple are stored by the NRF (402) within the node profile information.

12. The network node (900) of any of claims 8 to 11, wherein the processing circuitry is further configured to: receive (506), from a Home Subscriber Server, HSS, (102) a node profile information request comprising the instance identifier associated with the NF (104); and provide (508), to the HSS (102), the node event capability information associated with the NF (104) within the node profile information.

13. The network node (900) of any of claims 8 to 12, wherein the processing circuitry is further configured to: receive (606), from a consumer node (202), a node profile information request comprising an NF type associated with the NF (104); andprovide (608), to the consumer node (202) via a registrar function (402), the node event capability information associated with the NF (104) within the node profile information.

14. The network node (900) of any of claims 8 to 13, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

15. A computer-readable medium that stores computer-executable instructions that, when executed by a processor, cause the processor to implement a method according to any one of claims 1 to 7.

16. A method of registering network function event capabilities performed by a Network Function, NF, (104) the method comprising: providing (404), to a Network Repository Function, NRF, (402), a registration request comprising an instance identifier associated with the NF (104) and node event capability information associated with the NF (104), wherein the node event capability information identifies event identifiers supported by the NF (104).

17. The method of claim 16, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

18. A network node (900) configured to implement a Network Function, NF, (104) for registering network function event capabilities, the network node (900) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: provide (404), to a Network Repository Function, NRF, (402), a registration request comprising an instance identifier associated with the NF (104) and node event capability information associated with the NF (104), wherein the node event capability information identifies event identifiers supported by the NF (104).

19. The network node (900) of claim 18, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

20. A computer-readable medium that stores computer-executable instructions that, when executed by a processor, cause the processor to implement a method according to any one of claims 16 to 17.

21. A method to retrieve network function event capabilities performed by a Home Subscriber Server, HSS, (102) the method comprising: providing (506), to Network Repository Function, NRF, (402) serving as a registrar function, a node profile information request comprising an instance identifier associated with a Network Function, NF, (104); and receiving (508), from the NRF (402), node event capability information associated with the NF (104) wherein the node event capability information identifies event identifiers supported by the NF (104).

22. The method of claim 21, further comprising: providing (510), to the NF (104), a subscription request based on the node event capability information associated with the NF (104).

23. The method of any of claims 21 to 22, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

24. A network node (900) configured to implement a Home Subscriber Server, HSS, (102) for retrieving network function event capabilities, the network node (900) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: provide (506), to Network Repository Function, NRF, (402) serving as a registrar function, a node profile information request comprising an instance identifier associated with a Network Function, NF, (104); and receive (508), from the NRF (402), node event capability information associated with the NF (104), wherein the node event capability information identifies event identifiers supported by the NF (104).

25. The network node (900) of claim 24, wherein the processing circuitry is further configured to: provide (510), to the NF (104), a subscription request based on the node event capability information associated with the NF (104).

26. The network node (900) of claim 23, wherein the NF (104) comprises an Internet Protocol, IP, Multimedia Subsystem, IMS, Application Server, AS (104).

27. A computer-readable medium that stores computer-executable instructions that, when executed by a processor, cause the processor to implement a method according to any one of claims 21 to 23.

28. A method to retrieve network function event capabilities of a Network Function, NF, (104) performed by a consumer node (202), the method comprising: providing (606), to a network repository function, NRF, (402), a node profile information request comprising an NF type associated with the NF (104); and receiving (608), from the NRF (402), the node event capability information associated with the NF (104) within node profile information.

29. The method of claim 21, further comprising: providing (610), to the NF (104), a subscription request based on the node event capability information associated with the NF (104).

30. A network node (900) configured to implement a consumer node (202) for retrieving network function event capabilities of a Network Function, NF (104), the network node (900) comprising a network interface configured to communicate with other network nodes, and processing circuitry configured to: provide (606), to a network repository function, NRF, (402), a node profile information request comprising an NF type associated with the NF (104); and receive (608), from the NRF (402), the node event capability information associated with the NF (104).

31. The network node (900) of claim 30, wherein the processing circuitry is further configured to: provide (610), to the NF (104), a subscription request based on the node event capability information associated with the NF (104).

32. A computer-readable medium that stores computer-executable instructions that, when executed by a processor, cause the processor to implement a method according to claims 28 to 29.