WO2021027599A1

WO2021027599A1 - Method and apparatus for application load and/or overload control

Info

Publication number: WO2021027599A1
Application number: PCT/CN2020/106283
Authority: WO
Inventors: Ting Zhu; Yong Yang; Zhansheng WEI
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2019-08-09
Filing date: 2020-07-31
Publication date: 2021-02-18
Also published as: CN114208254A

Abstract

Embodiments of the present disclosure provide method and apparatus for application load control and/or application overload control. A method at a control plane function comprises receiving application load control information and/or application overload control information from a user plane function. The method further comprises processing the application load control information and/or application overload control information.

Description

METHOD AND APPARATUS FOR APPLICATION LOAD AND/OR OVERLOAD CONTROL

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 application load control and/or application overload control.

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.

As described in 3rd Generation Partnership Project (3GPP) TS 29.244 V16.0.0, the disclosure of which is incorporated by reference herein in its entirety, in CUPS (control and user plane separation) and 5GC (the fifth generation core network) , node level load control in user plane (UP) function is an optional feature defined over Sxa, Sxb, Sxc and N4 reference points. The node level load control enables the UP function to send its node level load information to a peer control plane (CP) function (s) to adaptively balance packet forwarding control protocol (PFCP) session load across the UP functions according to their effective node level load. The node level load information reflects the operating status of the resources of the UP function. The node level load control allows for better balancing of the PFCP session load, so as to attempt to prevent overload in the first place (preventive action) . The node level load control does not trigger overload mitigation actions even if the UP function reports a high load. The UP function may signal its node level load control information by Load Control Information IE (information element) to reflect the operating status of its resources, at the node level, via PFCP Session Establishment Response for the CP function to augment the UP function selection procedures.

Node level overload control is an optional feature which enables a UP function becoming or being overloaded to gracefully reduce its incoming signaling load by instructing its peer CP function (s) to reduce sending traffic according to its available signaling capacity to successfully process the traffic. A UP function is in overload when it operates over its signaling capacity which results in diminished performance (including impacts to handling of incoming and outgoing traffic) . Node level overload control may aim at shedding the incoming traffic as close to the traffic source as possible generally when an overload has occurred (reactive action) , so to avoid spreading the problem inside the network and to avoid using resources of intermediate nodes in the network for signaling that would anyhow be discarded by the overloaded node. Node level overload control information provides guidance to the CP functions to decide actions which may lead to signaling traffic mitigation towards the sender of the information. This may help in preventing severe overload and hence potential breakdown of the UP function. The UP function may signal its node level overload control information by Overload Control Information IE within PFCP Session Establishment Response.

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.

According to 3GPP TS 29.244 V16.0.0, UP function load control information doesn’t involve a service level (such as application type/ID (identifier) or network Instance) yet. In generally, UP function may need to process different application types, such as URLLC (ultra reliable low latency communications) with ultra-reliable of for example 99.999%and low latency of for example 5ms, eMBB (enhanced mobile broadband) with high throughput, and mMTC (massive machine type communications) with massive terminals. Sometimes the node level load control can’t reflect real load information for some services with different QoS (quality of service) requirements. For example, the URLLC service is on a larger scale and under the demanded service level even if the current node level load of UP Function is under control and not overloaded.

In addition, UP function may need to process traffic to different network instance, such as telematics, insurance, or social network. Each network instance may have different demands for service quality, for example, for telematics such as automatic driving, low latency is demanded, while for social network such as WeChat, latency is of low priority.

Moreover, UP function selection may be performed based on UP function dynamic load. If subsequent sessions are still delivered to the UP function whose load is under control, then it may cause further worse for some application types with high priority. In another hand, some application types with low priority (e.g. Water Metering) can be delivered to this UP function even if its current load is very high or overloaded.

Therefore the node level load control and node level overload control are not enough. To overcome or mitigate at least one above mentioned problems or other problems or provide a useful solution, the service/application level load control and service/application level overload control may be desirable.

In some embodiments of the present disclosure, the CP or UP function may initiate a PFCP association setup/update procedure to request to setup/update an PFCP association towards a UP or CP function. The CP function may provision the UP function with a list of features (which may affect the UP-function behavior) the CP function supports. The feature negotiation may be done by including CP functions features IE or UP functions features IE in the PFCP association setup/update request/response message by a CP function or a UP function, where CP functions features IE or UP functions features IE may take the form of a bitmask where each bit set indicates that the corresponding feature is supported. A new bit may represent the support of a new feature which may be called "the support of Application Load Control ( ‘APPL’ ) feature" in CP and UP Function Features. Another new bit may represent the support of another new feature which may be called "the support of Application Overload Control feature (APPOV) " in CP and UP Function Features.

In some embodiments of the present disclosure, once the UP function and CP function have indicated their support of this new feature by setting a corresponding bit to for example "1" in the PFCP association setup/update request/response message, the UP function will activate the application load and/or overload control feature, i.e. to measure the load condition per application type level.

In some embodiments of the present disclosure, an application type may be formed/classified by at least one of a number of applications with similar traffic model, e.g. with similar QoS requirements; a number of network slices, where network slices may differ for supported features and network functions optimizations, or multiple network slices delivering exactly the same features but for different groups of UEs, some typical slice/service type for example as specified in 3GPP TS 23.501 V16.0.2, URLLC, eMBB, V2X (Vehicle-to-everything) and mIoT (Mobile IoT (Internet of Things) ) ; a number of different transport networks, which may be represented by different network instances correspondingly, e.g. a Gigabit Ethernet, a MPLS (Multiprotocol Label Switching) network, etc.

In some embodiments of the present disclosure, an application type for load control monitoring can include one or more application ID (s) , one or more network instance (s) , or other categories. The definition of application type can be dynamically delivered from the CP function to the UP function via a PFCP association setup/update request/response message. The UP function is able to derive the application type to which a PFCP session pertain.

In some embodiments of the present disclosure, the CP function may include the relevant application type, by provisioning a new information element, for example called "application type indication" in the PFCP session establishment request message.

In some embodiments of the present disclosure, the application load and/or overload control information for a specific application type may be included in the PFCP session establishment, modification or delete response, or session report request messages by the UP function if the feature and specific application type is supported, even if the current PFCP session triggering above PFCP signaling messages is not for that application type.

In some embodiments of the present disclosure, another new feature, for example called "Application Overload Control" may be provided, which has very similar principles as the Application Load Control Information.

In some embodiments of the present disclosure, the Load Control calculation may be UP Function dependency, e.g. static deployment resource for application type or dynamic adjustment source in UP Function.

In some embodiments of the present disclosure, the handle of load control/overload control for application type may be CP function dependency.

In a first aspect of the disclosure, there is provided a method at a control plane function. The method comprises receiving application load control information and/or application overload control information from a user plane function. The method further comprises processing the application load control information and/or application overload control information.

In an embodiment, the method may further comprise sending a control plane function features information element to the user plane function. The method may further comprise receiving a user plane function features information element from the user plane function. The control plane function features information element may include a first indicator indicating whether the application load and/or overload control information is supported in the control plane function. The user plane function features information element may include a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.

In an embodiment, the control plane function may send the control plane function features information element and receive the user plane function features information element during a packet forwarding control protocol (PFCP) association setup or update procedure.

In an embodiment, the first indicator may be a bit and the second indicator may be a bit.

In an embodiment, when the application load and/or overload control information is supported in the control plane function, the control plane function features information element may further include at least one first application type indication each of which indicates whether the application load and/or overload control information of a corresponding first application type is supported in the control plane function. When the application load and/or overload control information is supported in the user plane function, the user plane function features information element may further include at least one second application type indication each of which indicates whether the application load and/or overload control information of a corresponding second application type is supported in the user plane function.

In an embodiment, each of the at least one first application type indication may be a bit and each of the at least one second application type indication may be a bit.

In an embodiment, an application type may be classified by at least one of at least one traffic model; at least one network slice; at least one network instance; at least one application identifier; at least one service data flow identifier; and at least one user equipment category.

In an embodiment, a definition of application type may be preconfigured in the control plane function and the user plane function or dynamically delivered from the control plane function to the user plane function via a packet forwarding control protocol (PFCP) association setup or update procedure.

In an embodiment, an application type indication may be carried in a packet forwarding control protocol (PFCP) session establishment or modification request message.

In an embodiment, the application load control information and/or the application overload control information may be received in a packet forwarding control protocol (PFCP) session establishment response message, a PFCP session modification response message, a PFCP session deletion response message, or a PFCP session report request message.

In an embodiment, the application load control information may include a load control sequence number, at least one application type indication, and a list of load metric matching the at least one application type indication.

In an embodiment, the application overload control information may include an indication indicating whether the application overload control information for a specific application type is included and an application type indication of the specific application type when the application overload control information for the specific application type is included.

In an embodiment, the control plane function may be one of packet data network (PDN) gateway control plane function (PGW-C) , serving gateway control plane function (SGW-C) , traffic detection function control plane function (TDF-C) , and session management function (SMF) . The user plane function may be one of PDN gateway user plane function (PGW-U) , serving gateway user plane function (SGW-U) , traffic detection function user plane function (TDF-U) and user plane function (UPF) .

In a second aspect of the disclosure, there is provided a method at a user plane function. The method comprises generating application load control information and/or application overload control information. The method further comprises sending the application load control information and/or application overload control information to a control plane function.

In an embodiment, the method may further comprise receiving a control plane function features information element from the control plane function. The method may further comprise sending a user plane function features information element to the control plane function. The control plane function features information element may include a first indicator indicating whether the application load and/or overload control information is supported in the control plane function. The user plane function features information element may include a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.

In an embodiment, the user plane function may receive the control plane function features information element and send the user plane function features information element during a packet forwarding control protocol (PFCP) association setup or update procedure.

In an embodiment, the application load control information and/or the application overload control information may be sent in a packet forwarding control protocol (PFCP) session establishment response message, a PFCP session modification response message, a PFCP session deletion response message, or a PFCP session report request message.

In a third aspect of the disclosure, there is provided an apparatus at a control plane function. The apparatus comprises a processor; and a memory coupled to the processor, said memory containing instructions executable by said processor, whereby said apparatus is operative to receive application load control information and/or application overload control information from a user plane function. Said apparatus is further operative to process the application load control information and/or application overload control information.

In a fourth aspect of the disclosure, there is provided an apparatus at a user plane function. The apparatus comprises a processor; and a memory coupled to the processor, said memory containing instructions executable by said processor, whereby said apparatus is operative to generate application load control information and/or application overload control information. Said apparatus is further operative to send the application load control information and/or application overload control information to a control plane function.

In a fifth aspect of the disclosure, there is provided a control plane function. The control plane function comprises a first receiving module configured to receive application load control information and/or application overload control information from a user plane function. The control plane function further comprises a processing module configured to process the application load control information and/or application overload control information.

In an embodiment, the control plane function may further comprise a sending module (optional) configured to send a control plane function features information element to the user plane function. The control plane function features information element includes a first indicator indicating whether the application load and/or overload control information is supported in the control plane function. The control plane function may further comprise a second receiving module (optional) configured to receive a user plane function features information element from the user plane function. The user plane function features information element includes a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.

In a sixth aspect of the disclosure, there is provided a user plane function. The user plane function comprises a generating module configured to generate application load control information and/or application overload control information. The user plane function further comprises a first sending module configured to send the application load control information and/or application overload control information to a control plane function.

In an embodiment, the user plane function may further comprise a receiving module (optional) configured to receive a control plane function features information element from the control plane function. The control plane function features information element includes a first indicator indicating whether the application load and/or overload control information is supported in the control plane function. The user plane function may further comprise a second sending module (optional) configured to send a user plane function features information element to the control plane function. The user plane function features information element includes a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.

In another aspect of the disclosure, there is provided a computer program product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to the first aspect of the disclosure.

In another aspect of the disclosure, there is provided a computer program product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to the second aspect of the disclosure.

In another aspect of the disclosure, there is provided a computer-readable storage medium storing instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to the first aspect of the disclosure.

In another aspect of the disclosure, there is provided a computer-readable storage medium storing instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to the second aspect of the disclosure.

Many advantages may be achieved by applying the proposed solution according to embodiments of the present disclosure. For example, load control information and overload control based on application level can reflect the real service load instead of node level load. After receiving application load control and/or application overload control information, the control plane function can handle subsequent operation, such as select or reselect UP Function for specific application type, adjust the slice resource for application type, etc. to ensure the QoS of application.

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. 1 schematically shows a system according to an embodiment of the present disclosure;

FIG. 2 schematically shows another system according to an embodiment of the present disclosure;

FIG. 3 shows a flowchart of a method according to an embodiment of the present disclosure;

FIG. 4 schematically shows an example for application type definition according to an embodiment of the present disclosure;

FIG. 5 shows a flowchart of a method according to another embodiment of the present disclosure;

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

FIG. 7 shows a flowchart of a method according to another embodiment of the present disclosure;

FIG. 8a illustrate a simplified block diagram of an apparatus according to an embodiment of the present disclosure;

FIG. 8b illustrate a simplified block diagram of an apparatus according to another embodiment of the present disclosure;

FIG. 9 illustrate a simplified block diagram of a control plane function according to an embodiment of the present disclosure; and

FIG. 10 illustrate a simplified block diagram of a user plane function according to an embodiment of the present 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 wireless 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 as may comprise the first generation (1G) , 2G, 3G, 4G, 4.5G, 5G communication protocols, and/or any other protocols either currently known or to be developed in the future.

The term “network device” or “network node” used herein refers to a network device such as a core network device in a communication network. For example, in a wireless communication network such as a 3GPP-type cellular network, the network node may comprise a control plane function (e.g., SMF, PGW-C and SGW-C) and a user plane function (e.g., UPF, PGW-U and SGW-U) , etc., which may offer numerous services to customers who are interconnected by an access network device. Each access network device is connectable to the core network device over a wired or wireless connection.

The term “network function (NF) ” refers to any suitable function which can be implemented in a network node (physical or virtual) such as a core network node of a communication network. For example, the 5G system (5GS) may comprise a plurality of NFs such as AMF (Access and mobility Function) , SMF (Session Management Function) , AUSF (Authentication Service Function) , UDM (Unified Data Management) , PCF (Policy Control Function) , AF (Application Function) , NEF (Network Exposure Function) , UPF (User plane Function) and NRF (NF Repository Function) , RAN (radio access network) , etc. In other embodiments, the network function may comprise different types of NFs for example depending on a specific type of network.

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, 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.

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 FIG. 1 and FIG. 2. For simplicity, the system architectures of FIGs. 1-2 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. 1 schematically shows a system according to an embodiment of the present disclosure. As shown in FIG. 1, the system 100 may comprise a PGW-C 102, a PGW-U 104, a SGW-C 106, a SGW-U 108, a UE 112, an eNodeB (eNB) 122, and a packet data network 114. User plane paths 116, 118 , 120, and 124 may be used by the UE 112 to connect to the packet data network 114. It is noted that the user plane paths 116, 118 and 120 may include any other suitable network devices (not shown in FIG. 1) . The system 100 may be CUPS architecture as defined in 3GPP TS23.214 V16.0.0. With CUPS, Sxb interface is defined between PGW-C and PGW-U, Sxa interface is defined between SGW-C and SGW-U, and S5/S8 control plane interface is defined between PGW-C and SGW-C. This enables flexible network deployment and operation and the independent scaling between control plane and user plane functions while not affecting the functionality of the existing nodes subject to this split. It is noted that there may be multiple UEs though only one UE is shown in the system 100. Each PGW-C may manage/control one or more PGW-Us though only one PGW-U is shown in the system 100. Each SGW-C may manage/control multiple SGW-Us though only one SGW-U is shown in the system 100. Each PGW-C may be connected to one or more SGW-Cs though only one SGW-C is shown in the system 100. Each SGW-C may be connected to one or more PGW-Cs though only one PGW-C is shown in the system 100.

FIG. 2 schematically shows a high level architecture in the next generation network such as 5G. The system architecture of FIG. 2 may comprise some exemplary elements such as AUSF, AMF, DN, NEF, NRF, NSSF, PCF, SMF, UDM, UPF, AF, UE, (R) AN.

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. 2. 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 packet 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. 2, the exemplary system architecture also contains the service-based interfaces such as Nnrf, Nnef, Nausf, Nudm, Npcf, Namf and Nsmf exhibited by NFs such as the NRF, the NEF, the AUSF, the UDM, the PCF, the AMF and the SMF. In addition, FIG. 2 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. 2 may be responsible for functions such as session management, mobility management, authentication, and security. These may be critical for delivering a service in the network. The AUSF, AMF, DN, NEF, NRF, NSSF, PCF, SMF, UDM, UPF, AF, UE, (R) AN may include the functionality for example as defined in clause 6.2 of 3GPP TS23.501 V15.4.0, the disclosure of which is incorporated by reference herein in its entirety. For example, the NEF may act as a gateway which can enable external users to monitor, provision and enforce an application policy for users inside the network. The AUSF may be configured as an authentication server. The UDM can store subscriber data and profiles. The PCF can provide a policy framework incorporating network slicing, roaming and mobility management. The AMF can manage access control and mobility. The SMF can set up and manage sessions according to a network policy. The UPF can be deployed in various configurations and locations according to the service type.

FIG. 3 shows a flowchart of a method according to an embodiment of the present disclosure, which may be performed by an apparatus implemented in/at or communicatively coupled to a control plane function. As such, the apparatus may provide means for accomplishing various parts of the method 300 as well as means for accomplishing other processes in conjunction with other components. The control plane function may be any suitable entity or node which can implement the control plane function. For example, the control plane function may be SGW-C, PGW-C, traffic detection function control plane function (TDF-C) , or SMF, etc.

At block 302, the control plane function sends a control plane function features information element to the user plane function. The control plane function features information element may include a first indicator indicating whether the application load control information and/or application overload control information is supported in the control plane function. The first indicator may take any suitable form such as a bit. The control plane function features information element may further include any other suitable indicator indicating whether other control plane function feature is supported in the control plane function. For example, depending on the specific network, the control plane function may support different control plane function features.

In an embodiment, the control plane function features information element may take any suitable form. For example, the control plane function features information element may take a form of a bitmask where each bit set indicates that the corresponding feature is supported. Table 1 shows an example of the control plane function features information element.

Table 1

Table 1 is similar to CP Function Features as described in Figure 8.2.58-1 of 3GPP TS 29.244 V16.0.0. The control plane function features may be signalled in this IE. Spare bits may be ignored by the receiver. The same bitmask may be defined for any suitable interface such as PFCP interface between the CP function and the UP function.

The following table 2 specifies the CP features defined on PFCP interfaces and the interfaces on which they apply.

Table 2

Table 2 is similar to CP Function Features as described in Table 8.2.58-1 of 3GPP TS 29.244 V16.0.0 except the underlined content. It is noted that the feature “APPL” and/or “APPOV” may occupy any other suitable Feature Octet/Bit though it occupies Feature Octet/Bit “5/3” and “5/4” as shown in Table 2.

In an embodiment, when the application load and/or overload control information is supported in the control plane function, the control plane function features information element may further include at least one first application type indication each of which may indicate whether the application load and/or overload control information of a corresponding first application type is supported in the control plane function. The first application type indication may take any suitable form such as a bit. For example, the first application type indication may take a form of a bitmask where each bit set indicates that the application type is supported. The following table 3 specifies application type indications supported by the CP function defined on PFCP interfaces and the interfaces on which they apply.

Table 3

The load control for different application type may be marked by Feature Octet/Bit “6/x” , which can be configured standalone for example depending on the CP function such as PGW-C/SMF. For example, for an application type marked by “6/x” , it can be an application ID list involving one or more application ID (s) , or a network Instance list involving one or more network instance (s) , or a service data flow list involving one or more SDF (Service Data Flow) filters, or a slice list involving one or more slice ID (s) , etc.

If “APPL” and/or “APPOV” is enabled, the specific application type can be delivered from the subsequent “6/x” Octet /Bit. If “6/x” Octet/Bit is set, the specific application type is enabled. By default, none of application type is enabled if none of “6/x” Octet/Bit is set.

The control plane function features information element can be sent in any suitable message such as association setup/update request or response message. For example, in CUPS and 5GC, the PFCP association may be set up between the CP function and the UP function prior to establishing PFCP sessions on that UP function. The CP function can provision the UP function with the list of features (which may affect the UP function behavior) the CP function supports. When a PFCP association is established with a CP function, the UP function can update the CP function with the list of features it supports. For the feature of load control and/or overload control and/or application load control, the UP function can update the CP function with its load control information and/or overload control information and/or application load control information and/or application overload control information, if load control and/or overload control and/or application load control is supported by the CP and UP functions. Application load control can be triggered standalone without load control or overload control triggered.

It is noted that the features “APPT1” to “APPT8” may occupy any other suitable Feature Octet/Bit though they occupy Feature Octet/Bit “6/1” to “6/8” as shown in Table 3. In addition, there may be any other number of application type indications though table 3 only shows 8 application type indications. For example, when there are more than 8 application type indications, another one or more Feature Octets may be occupied.

At block 304, the control plane function receives a user plane function features information element from the user plane function. The user plane function features information element may include a second indicator indicating whether the application load and/or overload control information is supported in the user plane function. The second indicator may take any suitable form such as a bit. The user plane function features information element may further include any other suitable indicator indicating whether other user plane function feature is supported in the user plane function. For example, depending on the specific network, the user plane function may support different user plane function features.

In an embodiment, the user plane function features information element may take any suitable form. For example, the user plane function features information element may take a form of a bitmask where each bit set indicates that the corresponding feature is supported. Table 4 shows an example of the user plane function features information element.

Table 4

Table 4 is similar to UP Function Features as described in Figure 8.2.25-1 of 3GPP TS 29.244 V16.0.0. The user plane function features may be signalled in this IE. Spare bits may be ignored by the receiver. The same bitmask may be defined for any suitable interface such as PFCP interface between the CP function and the UP function.

The following table 5 specifies the UP features defined on PFCP interfaces and the interfaces on which they apply.

Table 5

Table 5 is similar to CP Function Features as described in Table 8.2.25-1 of 3GPP TS 29.244 V16.0.0 except the underlined content. It is noted that the feature “APPL” and “APPOV” may occupy any other suitable Feature Octet/Bit though it occupies Feature Octet/Bit “7/5” and “7/6” as shown in Table 5.

In an embodiment, when the application load and/or overload control information is supported in the user plane function, the user plane function features information element may further include at least one second application type indication each of which indicates whether the application load and/or overload control information of a corresponding second application type is supported in the user plane function. The second application type indication may take any suitable form such as a bit. For example, the second application type indication may take a form of a bitmask where each bit set indicates that the application type is supported. The following table 6 specifies application type indications supported by the UP function defined on PFCP interfaces and the interfaces on which they apply.

Table 6

The load control for different application types may be marked by Feature Octet/Bit “8/x” , which can be configured standalone for example depending on the CP function such as PGW-C/SMF. For example, for an application type marked by “8/x” , it can be an application ID list involving one or more application ID (s) , or a Network Instance list involving one or more network instance (s) , or a service data flow list involving one or more SDF (Service Data Flow) -filters, or a slice list involving one or more slice ID (s) , etc.

If “APPL” and/or “APPOV” is enabled, the specific application type can be delivered from the subsequent “8/x” Octet /Bit. If “8/x” Octet/Bit is set, the specific application type is enabled. By default, none of application type is enabled if none of “8/x” Octet/Bit is set.

The user plane function features information element can be received in any suitable message such as association setup/update request or response message. For example, in CUPS and 5GC, the UP function can provision the CP function with the list of features the UP function supports. When a PFCP association is established with a CP function, the UP function can update the CP function with the list of features it supports.

It is noted that the features “APPT1” to “APPT8” may occupy any other suitable feature Octet/Bit though they occupy Feature Octet/Bit “8/1” to “8/8” as shown in Table 6. In addition, there may be any other number of application type indications though table 6 only shows 8 application type indications. For example, when there are more than 8 application type indications, another one or more Feature Octets may be occupied.

In an embodiment, the control plane function may send the control plane function features information element and receive the user plane function features information element during a PFCP association setup or update procedure. For example, when the PFCP association setup or update procedure is initiated by the CP function, the control plane function may first send the control plane function features information element in a PFCP association setup or update request message and then receive the user plane function features information element in a PFCP association setup or update response message. When the PFCP association Setup or update procedure is initiated by the UP function, the control plane function may first receive the user plane function features information element in a PFCP association setup or update request message and then send the control plane function features information element in a PFCP association setup or update response message. In CUPS and 5GC, the PFCP association may be similar to the PFCP Association as described in clause 5.8 of 3GPP TS 29.244 V16.0.0.

The application type may be classified based on any suitable parameter (s) . For example, the application type can be “URLLC” , “mIoT” or “eMBB” , etc. In an embodiment, the application type may be classified by at least one of at least one traffic model; at least one network slice; at least one network instance; at least one application identifier; at least one service data flow identifier; and at least one user equipment category.

FIG. 4 schematically shows an example for application type definition according to an embodiment of the present disclosure. The application type definition may be delivered in any suitable message such as PFCP association setup/update request or response message. As shown in FIG. 4, there are three application types URLLC, MIOT and EMBB. The application type URLLC corresponds to application ID 1, application ID 2 and application ID 3 which may have a QoS Class Identifier (QCI) “a” . The application type MIOT corresponds to SDF filters 4 and SDF filters 5, which may have the QCI “b/c” . The application type EMBB corresponds to network instance 1, network instance 2 and network instance 3 which may have the QCI “d/e” . It is noted that the application type definition as shown in FIG. 4 is only for the purpose of illustration, and there may be any other suitable application type definition in other embodiments. For example, the application type may be defined by at least one of at least one traffic model; at least one network slice; at least one network instance; at least one application identifier; at least one service data flow identifier; and at least one user equipment category.

The application type definition information element may be defined for example when the application type definition may be required to be delivered for example from the CP function to the UP function. The application type definition information element may take any suitable form. For example table 7 shows an example of the application type definition information element.

Table 7

“Application Type Association” is used as an enumeration type, which may include one or more parameters corresponding to the Application Type Association, for example, the Network Instance=0, Application ID=1, SDF ID=2, Slice ID=3, UE Category=4, etc. The “APPL” , “OVRL” , “LOAD” , “APPT1” and “APPT2” may be similar to the corresponding parameters as described above. It is noted that the Application Type Association as shown in table 7 is only for the purpose of illustration, and there may be any other suitable Application Type Association in other embodiments.

In an embodiment, the definition of application type may be preconfigured in the control plane function and the user plane function or dynamically delivered from the control plane function to the user plane function via a PFCP association setup or update procedure. In addition, when the definition of application type is changed or updated, the definition of application type may be reconfigured in the control plane function and the user plane function or dynamically delivered from the control plane function to the user plane function via the PFCP association setup or update procedure.

In an embodiment, the application type indication may be carried in a PFCP session establishment or modification request message. For example, the application type indications can be delivered to the UP Function in PFCP session establishment/modification procedure for example when the application type definition is not supported in the UP function.

In an embodiment, Application Type Indications information element may be added in information elements in a PFCP Session Establishment Request. For example, Table 7.5.2.1-1 of 3GPP TS 29.244 V16.0.0 may be added the underlined content as following.

In an embodiment, Application Type Indications information element may be added in information elements in a PFCP Session Modification Request. For example, Table 7.5.4.1-1 of 3GPP TS 29.244 V16.0.0 may be added the underlined content as following.

FIG. 5 shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in/at or communicatively coupled to a control plane function. As such, the apparatus may provide means for accomplishing various parts of the method 500 as well as means for accomplishing other processes in conjunction with other components. The control plane function may be any suitable entity or node which can implement the control plane function. For example, the control plane function may be SGW-C, PGW-C, TDF-C, or SMF, etc. It is noted that before the control plane function performs the method 500, it may perform the method 300.

At block 502, the control plane function receives application load control information and/or application overload control information from the user plane function. The application load control information and/or application overload control information can be received in any suitable message. For example, the load and/or overload control information of one or more specific application types may be received in a PFCP session establishment or modification or delete response, or PFCP session report request. It is noted that the load and/or overload control information of one or more specific application types may be received in any PFCP session establishment or modification or delete response, or PFCP session report request even if the involved application type (such as classified by application ID) is not hit by these messages.

In an embodiment, the application load and/or overload control information may be added in information elements in a PFCP Session Establishment Response. For example, Table 7.5.3.1-1 of 3GPP TS 29.244 V16.0.0 may be added the underlined content as following.

In an embodiment, the application load and/or overload control information may be added in information elements in a PFCP Session Modification Response. For example, Table 7.5.5.1-1 of 3GPP TS 29.244 V16.0.0 may be added the underlined content as following.

In an embodiment, the application load and/or overload control information may be added in information elements in a PFCP Session Deletion Response. For example, Table 7.5.7.1-1 of 3GPP TS 29.244 V16.0.0 may be added the underlined content as following.

In an embodiment, the application load and/or overload control information may be added in information elements in a PFCF Session Report Request. For example, Table 7.5.8-1 of 3GPP TS 29.244 V16.0.0 may be added the underlined content as following.

The application load control information may include at least one load parameter indicating a current load level for at least one application type. The computation of the current load level for a specific application type may use any suitable approaches and the present disclosure has no limit on it. For example, the computation may consider various aspects, such as the used capacity allocated for the specific application type.

In an embodiment, the application load control information may include a load control sequence number, at least one application type indication, and a list of load metric matching the at least one application type indication. For example, table 8 shows an example of application load control information.

Table 8

The Load Control Sequence number may contain a value that indicates the sequence number associated with the Application Load Control Information IE. This sequence number shall be used to differentiate any two Application Load Control Information IEs generated at two different instances by the same UP function. The Load Control Sequence Number shall be supported (if application load control information is supported) and shall always be present in the Application Load Control Information IE.

The UP function generating Application Load Control Information IE shall increment the Load Control Sequence Number whenever modifying some information in the Application Load Control Information IE. The Load Control Sequence Number shall not be incremented otherwise. The UP function may use the time, represented in an unsigned integer format, of the generation of the Application Load Control Information IE to populate the Load Control Sequence Number.

This parameter shall be used by the receiver of the Application Load Control Information IE to properly collate out-of-order application load control information, e.g. due to PFCP retransmissions. This parameter shall also be used by the receiver of the Application Load Control Information IE to determine whether the newly received Application Load Control Information has changed compared to application load control information previously received from the same node earlier.

If the receiving entity has already received and stored application load control information from the peer UP function, the receiving CP function shall update its application load control information only if the Load Control Sequence Number received in the new application load control information is higher than the stored value of the Load Control Sequence Number associated with the peer UP function. However due to roll-over of the Load Control Sequence Number or restart of the node, the Load Control Sequence Number may be reset to an appropriate base value by the peer UP function, hence the receiving entity shall be prepared to receive (and process) a Load Control Sequence Number parameter whose value is less than the previous value.

The metric information element may take any suitable form. For example, table 9 shows an example of metric information element. The metric information element may indicate a percentage and may take binary coded integer values form. The percentage can be within the range of 0 (including) to 100 (including) , where 0 means no or 0%load for a corresponding application type and 100 means maximum or 100%load reached for a corresponding application type.

Table 9

The load metric may be supported (if application load control is supported) . The load metric shall always be included in the application load control information.

Considering the processing requirement of the receiver of the application load control information (e.g. handling of the new application load control information, tuning the node selection algorithm to take the new application load control information into account) , the sender of the application load control information may refrain from advertising every small variation (e.g. with the granularity of 1 or 2) , in the load metric which does not result in useful improvement in node selection logic at the receiver. During the typical operating condition of the sender, a larger variation in the load metric, e.g. 5 or more units, may be considered as reasonable enough for advertising the new application load control information and thus justifying the processing requirement (to handle the new application load control information) of the receiver.

NOTE: The range of the load metric, i.e. 0 to 100, does not mandate the sender to collect application load control information at every increment/decrement and hence to advertise the change of load metric with a granularity of for example 1%. Based on various implementation specific criteria, such as: the architecture, session and signalling capacity, the current load and so on, the sender is free to define its own logic and periodicity with which application load control information is collected.

In an embodiment, the application overload control information may include an indication indicating whether the application overload control information for a specific application type is included and an application type indication of the specific application type when the application overload control information for the specific application type is included. The application overload control information can take any suitable form. For example, table 10 shows an example of the application overload control information. In “Overload Control Information Flags” IE, bit 2 flag or other bit flag of octet 5 may be set for application type. Table 10 is similar to Figure 8.2.76-1 of 3GPP TS 29.244 V16.0.0 except the underlined content.

Table 10

The following flags may be coded within Octet 5:

- Bit 1 –AOCI: Associate OCI with Node ID

- Bit 2 –OCIAPP: Associate OCI with Application Type: The UP function shall set this flag to 1 if it has included the "Overload Control Information" and if this information is to be associated with the specific Application Type (i.e. APPT1 defined in “Application Type Indications” ) of the serving UP function. This flag shall be set to 1 by the UP function, if the "Overload Control Information" is included in the PFCP Session Establishment Response and the Cause IE is set to a rejection cause value for specific Application Type.

- Bit 3 to 8: Spare, for future use and set to 0.

Note1: The Octet 6 is referred to “Application Type Indications” if Octet 5/Bit 2 for ‘OCIAPP’ is set as 1

Note2: only one Bit is enabled at the same time in Overload Control Information IE within PFCP Session Establishment/Modification since always the first Overload Threshold reached to report.

In an embodiment, the application overload control information may include a Application Overload Control Sequence Number, an application type indication, Application Overload Reduction Metric, Period of Validity, Application Overload Control Information Flags. For example, table 11 shows an example of application load control information.

Table 11

The application overload control may enable a UP function becoming or being overloaded for a specific application type to gracefully reduce its incoming signalling load for the specific application type by instructing its peer CP functions to reduce sending traffic for the specific application type according to its available signalling capacity for the specific application type to successfully process the traffic for the specific application type. A UP function is in overload for the specific application type when it operates over its signalling capacity for the specific application type which results in diminished performance (including impacts to handling of incoming and outgoing traffic for the specific application type) .

Application overload control may aim at shedding the incoming traffic for a specific application type as close to the traffic source as possible generally when an overload for the specific application type has occurred (reactive action) , so to avoid spreading the problem inside the network and to avoid using resources of intermediate nodes in the network for signalling for the specific application type that would anyhow be discarded by the overloaded node.

Application load control and application overload control may be supported and activated independently in the network, based on operator′s policy.

At block 504, the control plane function processes the application load control information and/or application overload control information. For example, the control plane function may store or update the application load control information and/or application overload control information. The selection of the UP function may be performed by the CP function such as SMF by considering the application load control information. Message throttling can be based on the application overload control information. For example, as part of the overload mitigation, a CP function shall reduce the total number of messages, which would have been sent otherwise, towards the overloaded peer based on the information received within the application Overload Control Information. This shall be achieved by discarding a fraction of the messages in proportion to the overload level of the target peer..

In various embodiments, the control plane function may be one of PGW-C, SGW-C, TDF-C, and SMF, and the user plane function may be one of PDN gateway user plane function (PGW-U) , serving gateway user plane function (SGW-U) , traffic detection function user plane function (TDF-U) and user plane function (UPF) .

FIG. 6 shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in/at a user plane function or communicatively coupled to a user plane function. As such, the apparatus may provide means for accomplishing various parts of the method 600 as well as means for accomplishing other processes in conjunction with other components. The user plane function may be any suitable node or entity (physical or virtual) which can implement the user plane function. For example, the user plane function may be SGW-U, PGW-U, TDF-U, or UPF, etc. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity.

At block 602, the user plane function receives a control plane function features information element from a control plane function. The control plane function features information element may include a first indicator indicating whether the application load and/or overload control information is supported in the control plane function The control plane function may be SGW-C, PGW-C, TDF-C, or SMF, etc. For example, the control plane function may send the control plane function features information element as described in block 304 of FIG. 3, then the user plane function may receive the control plane function features information element from the control plane function. The control plane function features information element may be received in any suitable message.

At block 604, the user plane function sends a user plane function features information element to the control plane function. The user plane function features information element may be sent in any suitable message.

In an embodiment, the user plane function may receive the control plane function features information element and send the user plane function features information element during a PFCP association setup or update procedure.

The first indicator and the second indicator may take any suitable form as described above. In an embodiment, the first indicator is a bit and the second indicator is a bit.

In an embodiment, when the application load and/or overload control information is supported in the control plane function, the control plane function features information element may further include at least one first application type indication each of which indicates whether the application load and/or overload control information of a corresponding first application type is supported in the control plane function.

In an embodiment, when the application load and/or overload control information is supported in the user plane function, the user plane function features information element may further include at least one second application type indication each of which indicates whether the application load and/or overload control information of a corresponding second application type is supported in the user plane function.

The at least one first application type indication and the at least one second application type indication may take any suitable form as described above. In an embodiment, each of the at least one first application type indication is a bit and each of the at least one second application type indication is a bit.

In an embodiment, an application type is classified by at least one of at least one traffic model; at least one network slice; at least one network instance; at least one application identifier; at least one service data flow identifier; and at least one user equipment category.

FIG. 7 shows a flowchart of a method according to another embodiment of the present disclosure, which may be performed by an apparatus implemented in/at a user plane function or communicatively coupled to a user plane function. As such, the apparatus may provide means for accomplishing various parts of the method 700 as well as means for accomplishing other processes in conjunction with other components. The user plane function may be any suitable node or entity (physical or virtual) which can implement the user plane function. For example, the user plane function may be SGW-U, PGW-U, TDF-U, or UPF, etc. For some parts which have been described in the above embodiments, the description thereof is omitted here for brevity. It is noted that before the user plane function performs the method 700, it may perform the method 600.

At block 702, the user plane function generates application load control information and/or application overload control information. For example, the user plane function may be free to define its own logic and periodicity with which application load control information and/or application overload control information is collected for example based on various implementation specific criteria, such as the architecture, session and signalling capacity, the current load and so on.

At block 704, the user plane function sends the application load control information and/or application overload control information to the control plane function. How often or when the user plane function sends the application load control information and/or application overload control information may be implementation specific. The user plane function may ensure that new/updated application load control information and/or application overload control information is propagated to the control plane function with an acceptable delay, such that the purpose of the information, (i.e. the effective application overload control protection) is achieved. The following are some of the potential approaches that the user plane function sends the application load control information and/or application overload control information to the control plane function:

- the user plane function may send the application load control information and/or application overload control information only when the new/changed value has not already been provided to the control plane function;

- the user plane function may send the application load control information and/or application overload control information in a subset of the messages towards the control plane function;

- the user plane function may send the application load control information and/or application overload control information periodically.

The user plane function may also implement a combination of one or more of the above approaches. Besides, the user plane function may also include the application load control information and/or application overload control information only in a subset of the applicable PFCP messages.

The control plane function may be prepared to receive the application load control information and/or application overload control information received in any of the PFCP messages extended with the application load control information and/or application overload control information and upon such reception, shall be able act upon the received information.

In an embodiment, the application load control information and/or the application overload control information may be sent in a PFCP session establishment response message, a PFCP session modification response message, a PFCP session deletion response message, or a PFCP session report request message.

FIG. 8a illustrates a simplified block diagram of an apparatus 810 that may be embodied in/as a control plane function according to an embodiment of the present disclosure. FIG. 8b illustrates an apparatus 820 that may be embodied in/as a user plane function according to an embodiment of the present disclosure.

The apparatus 810 may comprise at least one processor 811, such as a data processor (DP) and at least one memory (MEM) 812 coupled to the processor 811. The apparatus 810 may further comprise a transmitter TX and receiver RX 813 coupled to the processor 811. The MEM 812 stores a program (PROG) 814. The PROG 814 may include instructions that, when executed on the associated processor 811, enable the apparatus 810 to operate in accordance with the embodiments of the present disclosure, for example to perform the methods related to the control plane function as described above. A combination of the at least one processor 811 and the at least one MEM 812 may form processing means 815 adapted to implement various embodiments of the present disclosure.

The apparatus 820 comprises at least one processor 821, such as a DP, and at least one MEM 822 coupled to the processor 821. The apparatus 820 may further comprise a transmitter TX and receiver RX 823 coupled to the processor 821. The MEM 822 stores a PROG 824. The PROG 824 may include instructions that, when executed on the associated processor 821, enable the apparatus 820 to operate in accordance with the embodiments of the present disclosure, for example to perform the methods related to the user plane function as described above. A combination of the at least one processor 821 and the at least one MEM 822 may form processing means 825 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

processors

811 and 821, software, firmware, hardware or in a combination thereof.

The

MEMs

812 and 822 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 memory and removable memory, as non-limiting examples.

The

processors

811 and 821 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.

FIG. 9 illustrates a simplified block diagram of a control plane function according to an embodiment of the present disclosure. The control plane function may be one of PGW-C, SGW-C, TDF-C, and SMF. The control plane function 900 comprises a first receiving module 902 configured to receive application load control information and/or application overload control information from a user plane function. The control plane function 900 further comprises a processing module 904 configured to process the application load control information and/or application overload control information.

In an embodiment, the control plane function 900 may further comprise a sending module (optional) 906 configured to send a control plane function features information element to the user plane function. The control plane function features information element includes a first indicator indicating whether the application load and/or overload control information is supported in the control plane function. The control plane function 900 may further comprise a second receiving module (optional) 908 configured to receive a user plane function features information element from the user plane function. The user plane function features information element includes a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.

FIG. 10 illustrates a simplified block diagram of a user plane function according to an embodiment of the present disclosure. The user plane function may be one of PGW-U, SGW-U, TDF-U, and UPF. The user plane function 1000 comprises a generating module 1002 configured to generate application load control information and/or application overload control information. The user plane function 1000 further comprises a first sending module 1004 configured to send the application load control information and/or application overload control information to a control plane function.

In an embodiment, the user plane function 1000 may further comprise a receiving module (optional) 1006 configured to receive a control plane function features information element from the control plane function. The control plane function features information element includes a first indicator indicating whether the application load and/or overload control information is supported in the control plane function. The user plane function 1000 may further comprise a second sending module (optional) 1008 configured to send a user plane function features information element to the control plane function. The user plane function features information element includes a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.

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 the method related to the control plane function 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 the method related to the user plane function 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 perform the method related to the control plane function 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 perform the method related to the user plane function 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 (500) at a control plane function, comprising:

receiving (502) application load control information and/or application overload control information from a user plane function; and

processing (504) the application load control information and/or application overload control information.
The method according to claim 1, further comprising:

sending (302) a control plane function features information element to the user plane function;

receiving (304) a user plane function features information element from the user plane function,

wherein the control plane function features information element includes a first indicator indicating whether the application load and/or overload control information is supported in the control plane function, and

wherein the user plane function features information element includes a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.
The method according to claim 2, wherein the control plane function sends the control plane function features information element and receives the user plane function features information element during a packet forwarding control protocol (PFCP) association setup or update procedure.
The method according to any of claims 2-3, wherein the first indicator is a bit and the second indicator is a bit.
The method according to any of claims 2-4, wherein

when the application load and/or overload control information is supported in the control plane function, the control plane function features information element further includes at least one first application type indication each of which indicates whether the application load and/or overload control information of a corresponding first application type is supported in the control plane function, and

when the application load and/or overload control information is supported in the user plane function, the user plane function features information element further includes at least one second application type indication each of which indicates whether the application load and/or overload control information of a corresponding second application type is supported in the user plane function.
The method according to claim 5, wherein each of the at least one first application type indication is a bit and each of the at least one second application type indication is a bit.
The method according to any of claims 5-6, wherein an application type is classified by at least one of

at least one traffic model;

at least one network slice;

at least one network instance;

at least one application identifier;

at least one service data flow identifier; and

at least one user equipment category.
The method according to any of claims 5-7, wherein a definition of application type is preconfigured in the control plane function and the user plane function or dynamically delivered from the control plane function to the user plane function via a packet forwarding control protocol (PFCP) association setup or update procedure.
The method according to any of claims 5-8, wherein an application type indication is carried in a packet forwarding control protocol (PFCP) session establishment or modification request message.
The method according to any of claims 1-9, wherein the application load control information and/or the application overload control information is received in a packet forwarding control protocol (PFCP) session establishment response message, a PFCP session modification response message, a PFCP session deletion response message, or a PFCP session report request message.
The method according to any of claims 1-10, wherein the application load control information includes a load control sequence number, at least one application type indication, and a list of load metric matching the at least one application type indication.
The method according to any of claims 1-11, wherein the application overload control information includes an indication indicating whether the application overload control information for a specific application type is included and an application type indication of the specific application type when the application overload control information for the specific application type is included.
The method according to any of claims 1-12, wherein the control plane function is one of packet data network (PDN) gateway control plane function (PGW-C) , serving gateway control plane function (SGW-C) , traffic detection function control plane function (TDF-C) , and session management function (SMF) , and the user plane function is one of PDN gateway user plane function (PGW-U) , serving gateway user plane function (SGW-U) , traffic detection function user plane function (TDF-U) and user plane function (UPF) .
A method (700) at a user plane function, comprising:

generating (702) application load control information and/or application overload control information; and

sending (704) the application load control information and/or application overload control information to a control plane function.
The method according to claim 14, further comprising:

receiving (602) a control plane function features information element from the control plane function;

sending (604) a user plane function features information element to the control plane function,

wherein the control plane function features information element includes a first indicator indicating whether the application load and/or overload control information is supported in the control plane function, and

wherein the user plane function features information element includes a second indicator indicating whether the application load and/or overload control information is supported in the user plane function.
The method according to claim 15, wherein the user plane function receives the control plane function features information element and sends the user plane function features information element during a packet forwarding control protocol (PFCP) association setup or update procedure.
The method according to any of claims 15-16, wherein the first indicator is a bit and the second indicator is a bit.
The method according to any of claims 15-17, wherein

when the application load and/or overload control information is supported in the control plane function, the control plane function features information element further includes at least one first application type indication each of which indicates whether the application load and/or overload control information of a corresponding first application type is supported in the control plane function, and

when the application load and/or overload control information is supported in the user plane function, the user plane function features information element further includes at least one second application type indication each of which indicates whether the application load and/or overload control information of a corresponding second application type is supported in the user plane function.
The method according to claim 18, wherein each of the at least one first application type indication is a bit and each of the at least one second application type indication is a bit.
The method according to any of claims 18-19, wherein an application type is classified by at least one of

at least one traffic model;

at least one network slice;

at least one network instance;

at least one application identifier;

at least one service data flow identifier; and

at least one user equipment category.
The method according to any of claims 18-20, wherein a definition of application type is preconfigured in the control plane function and the user plane function or dynamically delivered from the control plane function to the user plane function via a packet forwarding control protocol (PFCP) association setup or update procedure.
The method according to any of claims 18-21, wherein an application type indication is carried in a packet forwarding control protocol (PFCP) session establishment or modification request message.
The method according to any of claims 14-22, wherein the application load control information and/or the application overload control information is sent in a packet forwarding control protocol (PFCP) session establishment response message, a PFCP session modification response message, a PFCP session deletion response message, or a PFCP session report request message.
The method according to any of claims 14-23, wherein the application load control information includes a load control sequence number, at least one application type indication, and a list of load metric matching the at least one application type indication.
The method according to any of claims 14-24, wherein the application overload control information includes an indication indicating whether the application overload control information for a specific application type is included and an application type indication of the specific application type when the application overload control information for the specific application type is included.
The method according to any of claims 14-25, wherein the control plane function is one of packet data network (PDN) gateway control plane function (PGW-C) , serving gateway control plane function (SGW-C) , traffic detection function control plane function (TDF-C) , and session management function (SMF) , and the user plane function is one of PDN gateway user plane function (PGW-U) , serving gateway user plane function (SGW-U) , traffic detection function user plane function (TDF-U) and user plane function (UPF) .
An apparatus (810) at a control plane function, comprising:

a processor (811) ; and

a memory (812) coupled to the processor (811) , said memory (812) containing instructions executable by said processor (811) , whereby said apparatus (810) is operative to:

receive application load control information and/or application overload control information from a user plane function; and

process the application load control information and/or application overload control information.
The apparatus according to claim 27, wherein the apparatus is further operative to perform the method of any one of claims 2 to 13.
An apparatus (820) at a user plane function, comprising:

a processor (821) ; and

a memory (822) coupled to the processor (821) , said memory (822) containing instructions executable by said processor (821) , whereby said apparatus (820) is operative to:

generate application load control information and/or application overload control information; and

send the application load control information and/or application overload control information to a control plane function.
The apparatus according to claim 29, wherein the apparatus is further operative to perform the method of any one of claims 15 to 26.
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 26.
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 of claims 1 to 26.