WO2025213404A1

WO2025213404A1 - Devices and methods for quality of service monitoring

Info

Publication number: WO2025213404A1
Application number: PCT/CN2024/087099
Authority: WO
Inventors: Chunhui Zhu; Gang Wang
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2024-04-10
Filing date: 2024-04-10
Publication date: 2025-10-16
Anticipated expiration: 2026-10-10

Abstract

Embodiments of the present disclosure provide a solution for Quality of Service (QoS) monitoring. In a solution, a first network device receives, from a second network device, a first message regarding a QoS monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and transmit, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

Description

DEVICES AND METHODS FOR QUALITY OF SERVICE MONITORING

FIELDS

Example embodiments of the present disclosure generally relate to the field of communication techniques and in particular, to devices and methods for Quality of Service (QoS) monitoring.

BACKGROUND

In a communication network, Quality of Service (QoS) monitoring ensures the network provides a required level of performance to meet the expectations of users and applications. An Application Function (AF) in the core network plays a significant role in managing and monitoring QoS for various services and applications. Specifically, the AF continuously monitors the performance of the network in terms of key performance indicators (KPIs) like throughput, latency, packet loss, and error rates. This monitoring helps to ensure that the network is meeting the QoS objectives.

By performing QoS monitoring, the AF in the core network helps to deliver a consistent and high-quality user experience, even under varying network conditions and with diverse application requirements. This is particularly important for time-sensitive applications like video streaming, online gaming, and voice over IP (VoIP) services, which require a stable and high-quality network connection to function effectively.

SUMMARY

In a first aspect, there is provided a first network device comprising: a processor configured to cause the first network device to: receive, from a second network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for a RAN QoS monitoring capability; and transmit, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In a second aspect, there is provided a second network device comprising: a processor configured to cause the second network device to: transmit, to a first network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for a RAN QoS monitoring capability; and receive, from the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In a third aspect, there is provided a communication method performed by a first network device. The method comprises: receiving, from a second network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for a RAN QoS monitoring capability; and transmitting, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In a fourth aspect, there is provided a communication method performed by a second network device. The method comprises: transmitting, to a first network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for a RAN QoS monitoring capability; and receiving, from the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In a fifth aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to the third, or fourth aspect.

Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some example embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

FIG. 1A illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

FIG. 1B illustrates another example communication environment in which example embodiments of the present disclosure can be implemented;

FIG. 2 illustrates a signaling flow of a procedure of QoS monitoring in accordance with some embodiments of the present disclosure;

FIG. 3 illustrates a signaling flow of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure;

FIG. 4 illustrates a signaling flow of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure;

FIG. 5 illustrates a signaling flow of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure;

FIG. 6 illustrates a signaling flow of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure;

FIG. 7 illustrates a signaling flow of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure;

FIG. 8 illustrates a flowchart of a method implemented at a first network device according to some example embodiments of the present disclosure;

FIG. 9 illustrates a flowchart of a method implemented at a second network device according to some example embodiments of the present disclosure;

FIG. 10 illustrates a simplified block diagram of an apparatus that is suitable for implementing example embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

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.

As used herein, the term ‘terminal device’ refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Ultra-reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, devices on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, devices for Integrated Access and Backhaul (IAB) , Space borne vehicles or Air borne vehicles in Non-terrestrial networks (NTN) including Satellites and High Altitude Platforms (HAPs) encompassing Unmanned Aircraft Systems (UAS) , eXtended Reality (XR) devices including different types of realities such as Augmented Reality (AR) , Mixed Reality (MR) and Virtual Reality (VR) , the unmanned aerial vehicle (UAV) commonly known as a drone which is an aircraft without any human pilot, devices on high speed train (HST) , or image capture devices such as digital cameras, sensors, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. The ‘terminal device’ can further has ‘multicast/broadcast’ feature, to support public safety and mission critical, V2X applications, transparent IPv4/IPv6 multicast delivery, IPTV, smart TV, radio services, software delivery over wireless, group communications and IoT applications. It may also incorporate one or multiple Subscriber Identity Module (SIM) as known as Multi-SIM. The term “terminal device” can be used interchangeably with a UE, a mobile station, a subscriber station, a mobile terminal, a user terminal or a wireless device.

The term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a transmission reception point (TRP) , a remote radio unit (RRU) , a radio head (RH) , a remote radio head (RRH) , an IAB node, a low power node such as a femto node, a pico node, a reconfigurable intelligent surface (RIS) , and the like.

The terminal device or the network device may have Artificial intelligence (AI) or Machine learning capability. It generally includes a model which has been trained from numerous collected data for a specific function, and can be used to predict some information.

The terminal or the network device may work on several frequency ranges, e.g., FR1 (e.g., 450 MHz to 6000 MHz) , FR2 (e.g., 24.25GHz to 52.6GHz) , frequency band larger than 100 GHz as well as Tera Hertz (THz) . It can further work on licensed/unlicensed/shared spectrum. The terminal device may have more than one connection with the network devices under Multi-Radio Dual Connectivity (MR-DC) application scenario. The terminal device or the network device can work on full duplex, flexible duplex and cross division duplex modes.

The embodiments of the present disclosure may be performed in test equipment, e.g., signal generator, signal analyzer, spectrum analyzer, network analyzer, test terminal device, test network device, channel emulator. In some embodiments, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In some embodiments, the first network device may be a first RAT device and the second network device may be a second RAT device. In some embodiments, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device or the second network device. In some embodiments, first information may be transmitted to the terminal device from the first network device and second information may be transmitted to the terminal device from the second network device directly or via the first network device. In some embodiments, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

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. The term ‘includes’ and its variants are to be read as open terms that mean ‘includes, but is not limited to. ’ The term ‘based on’ is to be read as ‘at least in part based on. ’ The term ‘one embodiment’ and ‘an embodiment’ are to be read as ‘at least one embodiment. ’ The term ‘another embodiment’ is to be read as ‘at least one other embodiment. ’ The terms ‘first, ’ ‘second, ’ and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as ‘best, ’ ‘lowest, ’ ‘highest, ’ ‘minimum, ’ ‘maximum, ’ or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

As used herein, the term “resource, ” “transmission resource, ” “uplink resource, ” or “downlink resource” may refer to any resource for performing a communication, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resources in other domains.

As used herein, unless stated explicitly, performing a step “in response to A” does not indicate that the step is performed immediately after “A” occurs and one or more intervening steps may be included.

Principles and implementations of the present disclosure will be described in detail below with reference to the figures.

FIG. 1A illustrates an example communication environment 100A in which example embodiments of the present disclosure can be implemented. In the communication environment 100A, a plurality of communication devices, including a terminal device 101, a network device 102, an Access and Mobility Management Function (AMF) device 103, a Service Management Function (SMF) device 104, a Policy Control Function (PCF) device 105 an Application Function (AF) device 106 and a User Plane Function (UPF) device 107.

The terminal device 101 may be a UE and the network device 102 may be a base station serving the UE, e.g., a gNB in a radio access network (RAN) . For purpose of discussion, the network device 102 may be referred to as RAN 102 serving the terminal device 101.

In the context of 5G networks, the terms AMF, SMF, PCF, and AF refer to network functions that play crucial roles in the management and operation of the network. These functions are part of the service-based architecture (SBA) introduced in 5G to facilitate a more flexible, modular, and scalable approach to network services. In embodiments of the present disclosure, a device implementing any of the above network functions may be referred to as the corresponding netwrok function device. For example, the device implementing AMF may be referred to as AMF device 103, the device implementing SMF may be referred to as SMF device 102, the device implementing PCF may be referred to as PCF device 105, and the device implementing AF may be referred to as AF device 106.

The AMF device 103 is responsible for managing the access and mobility of user devices (UE) in the network. It handles the procedures for initial network attachment, tracking area updates, and mobility management as the UE moves between different network coverage areas. The AMF device 103 also enforces security policies, manages subscriber profiles, and ensures that the UE is authorized to access network services.

The SMF device 104 manages the establishment, modification, and release of user sessions in the network. It is responsible for session continuity, ensuring that services are maintained even when the user moves or experiences network changes. The SMF device 104 allocates user plane resources and enforces Quality of Service (QoS) policies for each session, working closely with the Policy Control Function (PCF) to optimize resource usage.

The PCF device 105 is responsible for policy control and charging rules in the network. It defines the rules for QoS, charging, and other service-related policies based on subscriber profiles and service plans. The PCF device 105communicates with the SMF and other network functions to enforce these policies, ensuring that the network resources are allocated and charged appropriately. The PCF device 105also communicates with the AMF device 103.

The AF device 106 is responsible for application-specific functions and services. It provides the logic and processing for applications that require network support, such as video streaming, gaming, or IoT services. The AF device 106 interacts with the SMF device 104 to request and negotiate QoS parameters for specific services, ensuring that the network meets the requirements of the applications.

These functions work together to provide a seamless and efficient user experience in the network. The AMF ensures that devices can connect and move within the network, the SMF manages the sessions and maintains service continuity, the PCF enforces policies and controls charging, and the AF provides application-specific services and logic. This modular approach allows for flexibility and adaptability in the network.

It is to be understood that the number of devices and their connections shown in FIG. 1A are only for the purpose of illustration without suggesting any limitation. The communication environment 100A may include any suitable number of devices configured to implementing example embodiments of the present disclosure.

FIG. 1B illustrates a further example communication environment 100B in which embodiments of the present disclosure can be implemented. In the communication environment 100B, a first network device 110 and a second network device 120 can communicate with each other.

In some embodiments, the first network device 110 may be the AMF device 103 and the second network device 120 may the SMF device 104. Alternatively, in some embodiments, the first network device 110 may be the SMF device 104, and the second network device 120 may the PCF device 105. As a further alternative, the first network device 110 may be the PCF device 105, and the second network device 120 may the AF device 106. It is to be understood that these examples are just discussed for illustration rather than suggesting any limitation. In other embodiments of the present disclosure, the first network device 110 and the second network device 120 may be implemented as other suitable device or nodes.

In the following, for the purpose of illustration, some example embodiments are described with the terminal device 101 operating as a UE. The network device 102 may operate as a base station, for example, a gNB in a RAN. In some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

In some example embodiments, if the terminal device 101 is a terminal device and the network device 102 is a network device, a link from the network device 102 to the terminal device 101 is referred to as a downlink (DL) , while a link from the terminal device 101 to the network device 102 is referred to as an uplink (UL) . In DL, the network device 102 is a transmitting (TX) device (or a transmitter) and the terminal device 101 is a receiving (RX) device (or a receiver) . In UL, the terminal device 101 is a TX device (or a transmitter) and the network device 102 is a RX device (or a receiver) .

The communications in the communication environment 100A and/or 100 B may conform to any suitable standards including, but not limited to, Global System for Mobile Communications (GSM) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , New Radio (NR) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , GSM EDGE Radio Access Network (GERAN) , Machine Type Communication (MTC) and the like. The embodiments of the present disclosure may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or the sixth generation (6G) networks.

It is to be understood that the number of devices and their connections shown in FIGS. 1A and 1B are only for the purpose of illustration without suggesting any limitation. The communication environment 100A or 100B may include any suitable number of devices configured to implementing example embodiments of the present disclosure. Although not shown, it is to be understood that one or more additional devices may be located in the cell, and one or more additional cells may be deployed in the communication environment.

Reference is made to FIG. 2, which illustrates a signaling flow 200 of a process of QoS monitoring in accordance with some embodiments of the present disclosure. For the purposes of discussion, the signaling flow 200 will be discussed with reference to FIG. 1B, for example, by using the first network device 110 and the second network device 120.

In the signaling flow 200, the second network device transmits (205) a first message regarding a Quality of Service (QoS) monitoring on a terminal device to the first network device 110. The first message may include a QoS monitoring request, a subscription for the RAN QoS monitoring capability, and/or other suitable information.

The first network device 110 receives (210) the first message from the second network device 120. If the first message includes the QoS monitoring request, the first network device 110 will know that the QoS monitoring is requested to be performed. On the other hand, if the first message includes the subscription for the RAN QoS monitoring capability, the first network device 110 will understand that the second network device 120 would like to know updated information about a change of the RAN QoS monitoring capability and will provide it to the second network device 120 in response to the change.

The first network device 110 transmits (215) , to the second network device 120, a second message indicating the RAN QoS monitoring capability. The second message includes at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability. The cause is a reason why the QoS monitoring cannot be performed. In some embodiments, the cause indicates that the RAN does not support the QoS monitoring.

The second network device 120 receives (220) the second message from the first network device 110. In some cases, the second network device 120 receives (220) the second message including the cause for a failure of the QoS monitoring, it will know that the QoS monitoring request is denied by the first network device 110 and the reason for failing to perform the QoS monitoring is that the RAN does not support the QoS monitoring, which is indicated by the cause included in the second message.

In another case, the first network device 110, upon receiving the QoS monitoring request, transmits information about the RAN QoS monitoring capability directly to the second network device 120. Thus, when the second network device receives (220) the second message including such information, it will know whether the RAN can support the QoS monitoring.

Alternatively, the first message received (210) by the first network device 110 may include the subscription for the RAN QoS monitoring capability. In this case, if there is a change in the RAN QoS monitoring capability, for example, if a previous network device serving the terminal device 101 does not support the QoS monitoring while the current network device serving the terminal device 101 can support the QoS monitoring, the first network device 110 may transmit the updated information about the RAN QoS monitoring capability to the second network device. The updated information indicates the change of the RAN QoS monitoring capability.

In other words, in response to receiving the subscription for the QoS monitoring capability and in response to a change of the RAN QoS monitoring capability, the first network device 110 may transmit, to the second network device 120, the updated information about the RAN QoS monitoring capability.

As discussed with respect to FIG. 1B, in some embodiments, the first network device 110 implements an AMF, and the first network device 110 is also referred to as an AMF device, e.g., the AMF device 103. Meanwhile, the second network device 120 may implement a SMF, and the second network device 120 is also referred to as a SMF device, e.g., the SMF device 104. If the second network device 120, e.g., the SMF device 104 receives a QoS monitoring request from the PCF device 105, it may transmit, to the first network device 110, e.g., the AMF device 103, the first message comprising the QoS monitoring request. The first network device 110 (e.g., the AMF device 103) , upon receiving the first message comprising the QoS monitoring request, may determine whether a RAN serving the terminal device does not support the QoS monitoring.

In some embodiments, information about the RAN QoS monitoring capability is preconfigured at the first network device 110 (e.g., the AMF device) or obtained by the first network device 110 from a management device, for example, an Operation Administration and Maintenance (OAM) device or other suitable device that manages the information about the RAN QoS monitoring capability.

If the first network device 110 determines, based on the information about the RAN QoS monitoring capability, that the RAN does not support the QoS monitoring, it may transmit, to the second network device 120, the second message comprising the cause for the failure of the QoS monitoring. Otherwise, if the first network device 110 determines that the RAN supports the QoS monitoring, it may transmit, to a third network device in the RAN (for example, the gNB 102 shown in FIG. 1A) , a QoS monitoring request comprising a set of parameters for the QoS monitoring. The set of parameters may include, for example, but not limited to, a UL packet delay, a DL packet delay, a round trip packet delay, congestion, data rate, and/or other parameter (s) related to a QoS monitoring policy.

Then, the first network device 110, e.g., the AMF device 103 may receive, from the third network device, e.g., gNB 102, a QoS monitoring response comprising a result of the QoS monitoring and transmit the result of the QoS monitoring to the second network device 120, that is, the SMF device 104.

Accordingly, the second network device 120, that is, the SMF device 104, may receive the second message from the first network device 110. The second message may include the cause for the failure of the QoS monitoring in the case where the RAN serving the terminal device 101 does not support the QoS monitoring. Alternatively, the second message may include a result of the QoS monitoring in the case where the RAN supports the QoS monitoring.

In some embodiments, the first network device 110, e.g., the AMF device 103, may communicate with the PCF device 105 directly. In such a case, the PCF device 105 may transmit, to the AMF device 103, a third message comprising a subscription for the RAN QoS monitoring capability. Thus, the AMF device 103 may receive, from the PCF device 105, the third message comprising the subscription for the RAN QoS monitoring capability. If there is a change of the RAN QoS monitoring capability, the AMF device 103 may transmit, to the PCF device 105, updated information about the RAN QoS monitoring capability. As such, the PCF device 105 may receive, from the AMF device 103, updated information about the RAN QoS monitoring capability.

Alternatively, in some example embodiments, the first network device 110 implements a SMF, for example, it may be the SMF device 104 of FIG. 1A. In this case, the second network device 120 implements a PCF, for example, it may be the PCF device 105 of FIG. 1A. The second network device 120 (e.g., the PCF device 105) , if receiving the QoS monitoring request from an Application Function (AF) device, may transmit the first message comprising the QoS monitoring request to the first network device (e.g., the SMF device 104) . The first network device 110, i.e., the SMF device 104, upon receiving the first message including the QoS monitoring request, may determine whether the information about the RAN QoS monitoring capability (also referred to as capability information for short) is available. For example, it may search in local storage or memory to find whether it has stored the capability information. If the capability information has been stored at the SMF device 104, it may determine that the information about the RAN QoS monitoring capability is available.

In a case where the information about the RAN QoS monitoring capability is unavailable, the SMF device 104 may transmit the QoS monitoring request to the AMF device 103. Then, the SMF device 104 may receive, from the AMF device 103, a result of the QoS monitoring or a cause for the failure of the QoS monitoring, which depends on the implementations at the AMF device 103 and its related nodes. Then, the SMF device 104 may transmit, to the second network device 120 (the PCF device 105 in this case) , the second message comprising the result of the QoS monitoring or the cause for the failure of the QoS monitoring. That is, the second network device 120 (the PCF device 105) may receive, from the first network device 110 (the SMF 104) , the second message comprising a result of the QoS monitoring or the cause for the failure of the QoS monitoring in the case where the information about the RAN QoS monitoring capability is unavailable to the first network device 110.

Additionally, if the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, the first network device 110 (e.g., the SMF device 104) will know that the RAN (gNB) 102 does not support the QoS monitoring and thus may transmits, to the second network device 120 (e.g., the PCF device 105) , the second message comprising the cause for the failure of the QoS monitoring. Specifically, the cause indicates that the RAN does not support the QoS monitoring.

If the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring, the first network device 110 (e.g., the SMF device 104) may transmit the QoS monitoring request to the AMF device 103, receive a result of the QoS monitoring from the AMF device, and transmit the result of the QoS monitoring to the second network device 120.

As a further alternatively, in some example embodiments, the first network device 110 may implement a PCF, e.g., the PCF device 105, and the second network device 120 may implement an AF, e.g., the AF device 106.

In this case, first, the second network device 120 (e.g., the AF device 106) may determine whether the information about the RAN QoS monitoring capability is available. If not, it may transmit the first message comprising the QoS monitoring request to the first network device 110 (e.g., the PCF device 105) . As an alternatively, if the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device supports the QoS monitoring, the second network device 120 (e.g., the AF device 106) also transmits the first message comprising the QoS monitoring request to the first network device 110 (e.g., the PCF device 105) .

The first network device 110 (e.g., the PCF device 105) may, in response to receiving the first message comprising the QoS monitoring request, determine whether the information about the RAN QoS monitoring capability is available. If not, the first netwrok device 110 (e.g., the PCF device 105) transmits the QoS monitoring request to the SMF device 104 and receives, from the SMF device 104, a result of the QoS monitoring or a cause for the failure of the QoS monitoring. Then, the first netwrok device 110 (e.g., the PCF device 105) may transmit (215) the second message to the second network device 120 (e.g., the AF device 106) . In this situation, the second message may include the result of the QoS monitoring or the cause for the failure of the QoS monitoring.

On the other hand, if the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, the first netwrok device 110 (e.g., the PCF device 105) may transmit the second message comprising the cause for the failure of the QoS monitoring to the second network device 120.

Otherwise, if the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring, the first netwrok device 110 (e.g., the PCF device 105) may transmit the QoS monitoring request to the SMF device 104. Upon receiving a result of the QoS monitoring from the SMF device 104, the first netwrok device 110 (e.g., the PCF device 105) may transmit the result of the QoS monitoring to the second network device 120 (e.g., the AF device 106) .

In some cases where the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, the first message comprising the QoS monitoring request may be not transmitted to the first network device 110, e.g., the PCF device 105.

In this way, the RAN QoS monitoring capability can be used by the AMF device 103, the SMF device 104, the PCF device 105 or the AF device 106 to treat the QoS monitoring request to the RAN.

FIG. 3 illustrates a signaling flow 300 of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure. As shown in FIG 3, the signaling flow 300 involves a UE 301, a gNB 302, an AMF device 303, an SMF device 304, a PCF device 305 and an AF device 306.

The UE 301 may be implemented as an example of the terminal device 101 of FIG. 1A. The gNB 302 (also referred to as the RAN 302 for purpose of discussion) may be implemented as an example of the network device 110 in FIG. 1A. The AMF device 303 (also referred to as the AMF 303 for purpose of discussion) may be implemented as an example of the AMF device 103 in FIG. 1A. The SMF device 304 (also referred to as the SMF 304 for purpose of discussion) may be implemented as an example of the SMF device 104 in FIG. 1A. The PCF device 305 (also referred to as the PCF 305 for purpose of discussion) may be implemented as an example of the PCF device 105 in FIG. 1A. The AF device 306 (also referred to as the AF 306 for purpose of discussion) may be implemented as an example of the AF device 106 in FIG. 1A.

In embodiments discussed with reference to FIG. 3, the AMF 303 may treat the QoS monitoring request based on the RAN QoS monitoring capability. In some embodiments, if the RAN supports QoS monitoring, the AMF 303 may proceed with the QoS monitoring and send the policy to RUN. If the RAN does not support QoS monitoring, the AMF rejects the QoS monitoring request and sends the cause to AF via SMF/PCF. The cause may be RAN does not support QoS monitoring.

Specifically, in the signaling flow 300, the AMF 303 treats the QoS monitoring request based on the RAN QoS monitoring capability. First, at 310, the UE 301 registers to the network (e.g., the RAN) and establishes a PDU session to access the AF 306.

In some cases, the AF 306 needs to perform the QoS monitoring on the UE 301, for example, monitor UE access and data transmitting QoS status. The AF 306 may send, at 311, a QoS monitoring request to the PCF 305. This request may include the QoS monitoring policy in PCC rule with the following: a UL packet delay, a DL packet delay, a round trip packet delay, congestion, a data rate etc. It is to be understood that the above example parameters are discussed for illustration, rather than suggesting any limitations. Then, the PCF 305 may send, at 312, the QoS monitoring request to the SMF 304.

At 313, the SMF 304 may send the QoS monitoring request to the AMF 303. The AMF 303 may be pre-configured by the operator or may obtain the RAN/gNB QoS monitoring capability, for example from an OAM. Thus, the AMF 303 may receive the QoS monitoring request from SMF 304.

Optionally, in some embodiments, if the RAN supports the QoS monitoring, the AMF 304 may proceed with the QoS monitoring and send the QoS monitoring policy to the gNB 302 (e.g., the RAN) in a QoS monitoring request. Then, the gNB 302 (the RAN) may perform the QoS monitoring on the UE 301 and may transmit, at 315, the result of the QoS monitoring to the AMF 303. In some implementations, the QoS monitoring request may include a UL packet delay, a DL packet delay, a round trip packet delay, a congestion status, a data rate, etc. Correspondingly, the result of the QoS monitoring may indicate measurements or values of the UL packet delay, the DL packet delay, the round trip packet delay, the status of congestion, the data rate, etc..

As such, the AMF 303 may obtain the result of the QoS monitoring from the gNB 302. It is to be understood that steps 314 and 315 are optional and if the RAN does not support QoS monitoring, steps 314 and 315 may be skipped.

In the case where the AMF 303 receives the QoS monitoring result from gNB 302, at 316, it may send the result in a QoS monitoring response to the SMF 304. If the RAN does not support QoS monitoring, the AMF 303 may reject the QoS monitoring request and send the cause to the SMF 304 in the QoS monitoring response at 316. The cause may indicate that RAN does not support QoS monitoring.

At 317, the SMF 304 may send the QoS monitoring response to the PCF 305, which may include the result of the QoS monitoring or the cause for the failure of the QoS monitoring. At 318, the PCF 305 may send the QoS monitoring response to the AF 306 including the response received at 317 from the SMF 304.

FIG. 4 illustrates a signaling flow 400 of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure. As shown in FIG 4, the signaling flow 400 involves a UE 401, a gNB 402, an AMF device 403, an SMF device 404, a PCF device 405 and an AF device 406.

The UE 401 may be implemented as the terminal device 101 of FIG. 1 A. The gNB 402 may be implemented as the network device 110 in FIG. 1 A. The AMF device 403 may be implemented as the AMF device 103 in FIG. 1A. The SMF device 404 may be implemented as the SMF device 104 in FIG. 1A. The PCF device 405 may be implemented as the PCF device 105 in FIG. 1A. The AF device 406 may be implemented as the AF device 106 in FIG. 1A.

In the situation of embodiments of FIG. 4, the SMF 403 treats the QoS monitoring request based on the RAN QoS monitoring capability. Specifically, the SMF 404 subscribes the RAN QoS monitoring capability change to the AMF 403. The AMF 403 may report the RAN QoS monitoring capability change to the SMF 404. When the UE 401 moves to a new RAN node, e.g., a new gNB, the AMF 403 may compare the latest RAN QoS monitoring capability with the previous report to the SMF 404. If the RAN QoS monitoring capability changes, the AMF 403 may report the latest capability to the SMF 404. Otherwise, if it does not change, the AMF 403 does not need to report.

If the RAN supports QoS monitoring, the SMF 404 may proceed with the QoS monitoring and sends the policy to the RAN via the AMF 403. On the other hand, if the RAN does not support the QoS monitoring, the SMF 404 may reject the QoS monitoring request and send the cause to the AF 406 via the PCF 405. The cause may indicate that the RAN does not support QoS monitoring.

In the signaling flow 400, steps 410, 411 and 412 are similar as the steps 310, 311 and 312, and thus related details are not repeated here. At 413, the SMF 404 sends QoS monitoring request to the AMF 403. The request may include the subscription for RAN QoS monitoring capability change, i.e. the SMF 404 subscribes the RAN QoS monitoring capability change to the AMF 403.

Steps 414 to 418 are similar as the steps 314 and 318, and thus related details are not repeated here.

At 419, the UE 401 may connect to a new gNB, for example, due to moving of the UE 401.

At 420, the AMF 403 may compare the latest RAN QoS monitoring capability with the previous one, if it changes, the AMF 403 may report the latest one to the SMF 404, which may be reported via a new message or use an existing message with a new information element. On the other hand, if the RAN QoS monitoring capability does not change, the AMF 403 does not report.

At 421, when the SMF 404 receives the RAN QoS monitoring capability change report, it may send an acknowledgement (ACK) to the AMF 403 to confirm receiving the report which can be a new message or use the existing message with a new information element. The SMF 404 stores the latest RAN QoS monitoring capability.

Then, if the RAN supports QoS monitoring and the SMF 404 further receives a QoS monitoring request, similar to the QoS monitoring request of step 412, it may proceed with the QoS monitoring and send the policy to the gNB 402 (or RAN) via the AMF 403.

Alternatively, if the RAN does not support QoS monitoring, the SMF 404 may reject the following QoS monitoring request when it receives a QoS monitoring request again, and may send the cause to the AF 406 via the PCF 405. The cause may be that the RAN does not support QoS monitoring.

FIG. 5 illustrates a signaling flow 500 of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure. As shown in FIG 5, the signaling flow 500 involves a UE 501, a gNB 502, an AMF device 503, an SMF device 504, a PCF device 505 and an AF device 506.

The UE 501 may be implemented as the terminal device 101 of FIG. 1 A. The gNB 502 may be implemented as the network device 110 in FIG. 1 A. The AMF device 503 may be implemented as the AMF device 103 in FIG. 1A. The SMF device 504 may be implemented as the SMF device 104 in FIG. 1A. The PCF device 505 may be implemented as the PCF device 105 in FIG. 1A. The AF device 506 may be implemented as the AF device 106 in FIG. 1A.

In this case, the PCF 505 treats the QoS monitoring request based on the RAN QoS monitoring capability. Specifically, the PCF 505 subscribes the RAN QoS monitoring capability change to the SMF 504. The SMF 504 obtains the RAN QoS monitoring capability from the AMF 503 as embodiments in FIG. 4 or the existing solution in the draft CRs. The SMF 504 reports the RAN QoS monitoring capability to the PCF 505 in the first time and then reports when the capability changes.

The PCF 505 subscribes the RAN QoS monitoring capability change to the AMF 503 directly. The AMF 503 reports the RAN QoS monitoring capability to the PCF 505 in the first time and then reports when the capability changes. If the RAN supports QoS monitoring, the PCF 505 proceeds with the QoS monitoring and sends the policy to the RAN via the AMF 503/the SMF 504. If the RAN does not support QoS monitoring, the PCF 505 rejects the QoS monitoring request and sends the cause to the AF 506. The cause may be RAN does not support QoS monitoring.

In the signaling flow 500, steps 510 and 511 are similar as steps 310 and 311 discussed above, and thus are not detailed here.

At 512, the PCF 505 sends the QoS monitoring request to the SMF 504, which may include the subscription to subscribe the RAN QoS monitoring capability change from the SMF 504.

At 513, the SMF 504 sends QoS monitoring Request to the AMF 503, which may include the subscription to subscribe the RAN QoS monitoring capability change from the AMF 503.

steps 514 to 518 are similar as steps 314 to 318 discussed above, and thus are not detailed here.

At 519, the UE 501 connects to a new gNB e.g. when the UE 501 moves.

At 520, the AMF 503 compares the latest RAN QoS monitoring capability with the previous one, if it changes, the AMF 503 reports the latest one to the SMF 504, which can be a new message or use the existing message with a new information element; if it does not change, the AMF 503 does not report.

At 521, the SMF 504 obtains the updated RAN QoS monitoring capability from the AMF 503; the SMF 504 reports the updated RAN QoS monitoring capability to the PCF 505.

At 522, the PCF 505 sends RAN QoS monitoring capability update ACK to the SMF 504 to acknowledge receiving.

At 523, the SMF 504 sends RAN QoS monitoring capability update ACK to the AMF 503 to acknowledge receiving.

Then, if the RAN supports QoS monitoring, the PCF 505 proceeds the following QoS monitoring Request with the QoS monitoring and sends the policy to the RAN via the AMF 503/the SMF 504. Otherwise, if the RAN does not support QoS monitoring, the PCF 505 rejects the following QoS monitoring request and sends the cause to the AF 506. The cause can be RAN does not support QoS monitoring.

FIG. 6 illustrates a signaling flow 600 of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure. As shown in FIG 6, the signaling flow 600 involves a UE 601, a gNB 602, an AMF device 603, an SMF device 604, a PCF device 605 and an AF device 606.

The UE 601 may be implemented as the terminal device 101 of FIG. 1 A. The gNB 602 may be implemented as the network device 110 in FIG. 1 A. The AMF device 603 may be implemented as the AMF device 103 in FIG. 1A. The SMF device 604 may be implemented as the SMF device 104 in FIG. 1A. The PCF device 605 may be implemented as the PCF device 105 in FIG. 1A. The AF device 606 may be implemented as the AF device 106 in FIG. 1A.

Different from the embodiments of FIG. 5, in which the subscription from the PCF 505 to the AMF 503 is via the SMF 504, in embodiments of FIG. 6, the subscription from the PCF 605 to the AMF 603 is via the SMF 604.

In the signaling flow 600, steps 610 and 611 are similar as steps 610 and 611 discussed above, and thus are not detailed here.

At 612, the PCF 605 initiates the QoS monitoring procedures, which are similar as those discussed with reference to steps 312 to 317, and thus are not detailed here.

When the PCF 605 receives the QoS monitoring result from the SMF 604, it may send, at 613, the result in the QoS monitoring Response to the AF 606.

At 614, the PCF 605 sends a RAN QoS monitoring capability change subscription to the AMF 603 directly, to subscribe the RAN QoS monitoring capability change.

At 615, the AMF 603 sends RAN QoS monitoring capability change subscription ACK to the PCF 605 to acknowledge accepting the subscription, which may also include the current RAN QoS monitoring capability.

At 616, the UE 601 connects to a new gNB, e.g. when the UE 601 moves.

The AMF 603 compares the latest RAN QoS monitoring capability with the previous one. If it changes, the AMF 603 reports the latest one to the PCF 605 at 617; otherwise, if it does not change, the AMF 603 does not report.

At 618, the PCF 605 sends RAN QoS monitoring capability update ACK to the AMF 603 to acknowledge receiving the update.

Then, if the RAN supports QoS monitoring, the PCF 605 proceeds the following QoS monitoring Request with the QoS monitoring and sends the policy to the RAN via the AMF 603/the SMF 604. On the other hand, if the RAN does not support QoS monitoring, the PCF 605 rejects the following QoS monitoring request and sends the cause to the AF 606. The cause may be that the RAN does not support QoS monitoring.

FIG. 7 illustrates a signaling flow 700 of an example procedure of QoS monitoring in accordance with some embodiments of the present disclosure. As shown in FIG 7, the signaling flow 700 involves a UE 701, a gNB 702, an AMF device 703, an SMF device 704, a PCF device 705 and an AF device 706.

The UE 701 may be implemented as the terminal device 101 of FIG. 1 A. The gNB 702 may be implemented as the network device 110 in FIG. 1 A. The AMF device 703 may be implemented as the AMF device 103 in FIG. 1A. The SMF device 704 may be implemented as the SMF device 104 in FIG. 1A. The PCF device 705 may be implemented as the PCF device 105 in FIG. 1A. The AF device 706 may be implemented as the AF device 106 in FIG. 1A.

In this case, the AF 706 treats the QoS monitoring request based on the RAN QoS monitoring capability. Specifically, the AF 706 subscribes the RAN QoS monitoring capability change to the PCF 705, and the PCF 705 obtains the RAN QoS monitoring capability from the SMF 704 or the AMF 703. The PCF 705 reports the RAN QoS monitoring capability to the AF 706 in the first time and then reports when the capability changes.

If the RAN supports QoS monitoring, the AF 706 proceeds with the QoS monitoring and sends the policy to the RAN via the AMF 703/the SMF 704/the PCF 705; otherwise, if the RAN does not support QoS monitoring, the AF 706 does not send the QoS monitoring request.

In the signaling flow 700, steps 710 and 711 are similar as the steps 310 and 311 and are thus not detailed here.

In some embodiments, in addition to a set of parameters for performing the QoS monitoring, the QoS monitoring request transmitted at 711 may contain the subscription request to the PCF 705 for RAN QoS monitoring capability change.

At 712, the PCF 705 performs QoS monitoring procedures, which are similar as those discussed with reference to steps 312 to 317, and thus are not detailed here.

The PCF 705 subscribes the RAN QoS monitoring capability change event to the SMF 704 or the AMF 703.

At 713, the PCF 705 may send a QoS monitoring response to the AF 706, which includes the QoS monitoring result, RAN QoS monitoring capability and the successful indication of the AF 706 subscription to the RAN QoS monitoring capability change.

At 714, the UE 701 connects to a new gNB, e.g. the UE 701 moves. the PCF 705 obtains the RAN QoS monitoring capability from the SMF 704 or the AMF 703.

At 715, if the RAN QoS monitoring capability changes, the PCF 705 reports the latest RAN QoS monitoring capability to the AF 706.

At 716, the AF 706 sends RAN QoS monitoring capability update ACK to the PCF 705 to acknowledge receiving the update.

Then if the RAN supports QoS monitoring, the AF 706 proceeds with the QoS monitoring and sends the policy to the RAN via the AMF 703/the SMF 704/the PCF 705. Otherwise, if the RAN does not support QoS monitoring, the AF 706 does not send the QoS monitoring request.

In view of the above, to support QoS monitoring, the 5GC NFs (i.e. AMF) may be aware of gNB’s QoS monitoring capability, which may be forwarded to the SMF. Based on gNB’s QoS monitoring capability, the SMF may accept or reject the QoS monitoring service request from the AF.

With the proposed solutions, RAN QoS monitoring capability can be reported to various nodes, such as AMF, SMF, and PCF, and they may treat the above processes as discussed with reference to FIGS. 2 to 7. That is, the proposed solutions introduce the RAN QoS monitoring capability report to the SMF/PCF/AF and are used for the QoS monitoring request treatment.

In some embodiments, in the procedures e.g. UE Requested PDU Session Establishment, the AMF/SMF/PCF report the RAN QoS monitoring capability to the other NF(SMF/PCF) or AF, and the capability is used for the QoS monitoring request treatment.

FIG. 8 illustrates a flowchart of a communication method 800 implemented at a first network device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 800 will be described from the perspective of the first network device 110 in FIG. 1B.

At block 810, the first network device 110 receives, from a second network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device. The first message comprises at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability.

At block 820, the first network device 110 transmits, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In some example embodiments, the first network device is further caused to: in response to receiving the subscription for the QoS monitoring capability and in response to a change of the RAN QoS monitoring capability, transmit, to the second network device, the updated information about the RAN QoS monitoring capability.

In some example embodiments, the first network device implements an Access and Mobility Management Function (AMF) , and the second network device implements a Session Management Function (SMF) , and wherein the first network device is further caused to: in response to receiving the first message comprising the QoS monitoring request, determine whether a RAN serving the terminal device does not support the QoS monitoring; in accordance with a determination that the RAN does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and in accordance with a determination that the RAN supports the QoS monitoring, transmit, to a third network device in the RAN, a QoS monitoring request comprising a set of parameters for the QoS monitoring, and receive, from the third network device, a QoS monitoring response comprising a result of the QoS monitoring, and transmit, to the second network device, the result of the QoS monitoring.

In some example embodiments, the information about the RAN QoS monitoring capability is preconfigured at the first network device or obtained by the first network device from a management device.

In some example embodiments, the first network device is further caused to: receive, from a Policy Control Function (PCF) device, a third message comprising a subscription for the RAN QoS monitoring capability; and in response to a change of the RAN QoS monitoring capability, transmit, to the PCF device, updated information about the RAN QoS monitoring capability.

In some example embodiments, the first network device implements a Session Management Function (SMF) , and the second network device implements a Policy Control Function (PCF) , and wherein the first network device is further caused to: in response to receiving the first message comprising the QoS monitoring request, determine whether the information about the RAN QoS monitoring capability is available; in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable, transmit the QoS monitoring request to an Access and Mobility Management Function (AMF) device, receive, from the AMF device, a result of the QoS monitoring or a cause for the failure of the QoS monitoring, and transmit, to the second network device, the second message comprising the result of the QoS monitoring or the cause for the failure of the QoS monitoring.

In some example embodiments, the first network device is further caused to: in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring, transmit the QoS monitoring request to the AMF device, receive a result of the QoS monitoring from the AMF device, and transmit the result of the QoS monitoring to the second network device.

In some example embodiments, the first network device implements a Policy Control Function (PCF) , and the second network device implements an Application Function (AF) , and wherein the first network device is further caused to: in response to receiving the first message comprising the QoS monitoring request, determine whether the information about the RAN QoS monitoring capability is available; in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable, transmit the QoS monitoring request to a Session Management Function (SMF) device, receive, from the SMF device, a result of the QoS monitoring or a cause for the failure of the QoS monitoring, and transmit, to the second network device, the second message comprising the result of the QoS monitoring or the cause for the failure of the QoS monitoring.

In some example embodiments, the first network device is further caused to: in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring, transmit the QoS monitoring request to the SMF device, receive a result of the QoS monitoring from the SMF device, and transmit the result of the QoS monitoring to the second network device.

In some example embodiments, the first network device is further caused to: transmit, to an Access and Mobility Management Function (AMF) device, a third message comprising a subscription for the RAN QoS monitoring capability; and receive, from the AMF device, updated information about the RAN QoS monitoring capability.

In some example embodiments, the cause for the failure of the QoS monitoring indicates that the RAN does not support the QoS monitoring.

FIG. 9 illustrates a flowchart of a communication method 900 implemented at a second network device in accordance with some embodiments of the present disclosure. For the purpose of discussion, the method 900 will be described from the perspective of the second network device 120 in FIG. 1B.

At block 910, the second network device 120 transmits, to a first network device 110, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and

At block 920, the second network device 120 receives, from the second network device 120, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In some example embodiments, the subscription for the RAN QoS monitoring capability is transmitted to the first network device, and wherein the second network device is further caused to: receive, from the first network device, updated information about the RAN QoS monitoring capability.

In some example embodiments, the first network device implements an Access and Mobility Management Function (AMF) , and the second network device implements a Session Management Function (SMF) , and wherein the second network device is further caused to: in response to receiving the QoS monitoring request from a Policy Control Function (PCF) device, transmits, to the first network device, the first message comprising the QoS monitoring request; and receive the second message from the first network device, wherein the second message comprises the cause for the failure of the QoS monitoring and a RAN serving the terminal device does not support the QoS monitoring, or wherein the second message comprises a result of the QoS monitoring and the RAN supports the QoS monitoring.

In some example embodiments, the first network device implements a Session Management Function (SMF) , and the second network device implements a Policy Control Function (PCF) , and wherein the first network device is further caused to: in response to receiving the QoS monitoring request from an Application Function (AF) device, transmit the first message comprising the QoS monitoring request to the first network device; and receive, from the first network device, the second message comprising a result of the QoS monitoring or the cause for the failure of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is unavailable to the first network device.

In some example embodiments, the second network device is further caused to: receive, from the first network device, the second message comprising the cause for the failure of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring; or receive, from the first network device, the second message comprising the result of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring.

In some example embodiments, the first network device implements a Policy Control Function (PCF) , and the second network device implements an Application Function (AF) , and wherein the second network device is further caused to: determine whether the information about the RAN QoS monitoring capability is available; in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable, transmit the first message comprising the QoS monitoring request to the first network device; and in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device supports the QoS monitoring, transmit the first message comprising the QoS monitoring request to the first network device.

In some example embodiments, the second network device is further caused to: receive, from the first network device, the second message comprising the cause for the failure of the QoS monitoring, wherein the RAN does not support the QoS monitoring; or receive, from the first network device, the second message comprising a result of the QoS monitoring, wherein the RAN supports the QoS monitoring.

FIG. 10 is a simplified block diagram of a device 1000 that is suitable for implementing embodiments of the present disclosure. The device 1000 can be considered as a further example implementation of any of the devices as shown in FIG. 1 A or 1B. Accordingly, the device 1000 can be implemented at or as at least a part of the first network device 110 or the second network device 120.

As shown, the device 1000 includes a processor 1010, a memory 1020 coupled to the processor 1010, a suitable transceiver 1040 coupled to the processor 1010, and a communication interface coupled to the transceiver 1040. The memory 1020 stores at least a part of a program 1030. The transceiver 1040 may be for bidirectional communications or a unidirectional communication based on requirements. The transceiver 1040 may include at least one of a transmitter 1042 and a receiver 1044. The transmitter 1042 and the receiver 1044 may be functional modules or physical entities. The transceiver 1040 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2/Xn interface for bidirectional communications between eNBs/gNBs, S1/NG interface for communication between a Mobility Management Entity (MME) /Access and Mobility Management Function (AMF) /SGW/UPF and the eNB/gNB, Un interface for communication between the eNB/gNB and a relay node (RN) , or Uu interface for communication between the eNB/gNB and a terminal device.

The program 1030 is assumed to include program instructions that, when executed by the associated processor 1010, enable the device 1000 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to FIGS. 1 to 9. The embodiments herein may be implemented by computer software executable by the processor 1010 of the device 1000, or by hardware, or by a combination of software and hardware. The processor 1010 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 1010 and memory 1020 may form processing means 1050 adapted to implement various embodiments of the present disclosure.

The memory 1020 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 1020 is shown in the device 1000, there may be several physically distinct memory modules in the device 1000. The processor 1010 may be of any type suitable to the local technical network, 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. The device 1000 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

According to embodiments of the present disclosure, a first network device comprising a circuitry is provided. The circuitry is configured to: receive, from a second network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and transmit, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the first network device as discussed above.

According to embodiments of the present disclosure, a second network device comprising a circuitry is provided. The circuitry is configured to: transmit, to a first network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and receive, from the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability. According to embodiments of the present disclosure, the circuitry may be configured to perform any method implemented by the second network device as discussed above.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

According to embodiments of the present disclosure, a first network apparatus is provided. The first network apparatus comprises means for receiving, from a second network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and means for transmitting, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: means for a cause for a failure of the QoS monitoring, means for information about the RAN QoS monitoring capability, or means for updated information about the RAN QoS monitoring capability. In some embodiments, the first apparatus may comprise means for performing the respective operations of the method 800. In some example embodiments, the first apparatus may further comprise means for performing other operations in some example embodiments of the method 800. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

According to embodiments of the present disclosure, a second network apparatus is provided. The second network apparatus comprises means for transmitting, to a first network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and means for receiving, from the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: means for a cause for a failure of the QoS monitoring, means for information about the RAN QoS monitoring capability, or means for updated information about the RAN QoS monitoring capability. In some embodiments, the second apparatus may comprise means for performing the respective operations of the method 900. In some example embodiments, the second apparatus may further comprise means for performing other operations in some example embodiments of the method 900. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In summary, embodiments of the present disclosure provide the following aspects.

In an aspect, it is proposed a first network device comprising: a processor configured to cause the first network device to: receive, from a second network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and transmit, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In some embodiments, the first network device is further caused to: in response to receiving the subscription for the QoS monitoring capability and in response to a change of the RAN QoS monitoring capability, transmit, to the second network device, the updated information about the RAN QoS monitoring capability.

In some embodiments, the first network device implements an Access and Mobility Management Function (AMF) , and the second network device implements a Session Management Function (SMF) , and wherein the first network device is further caused to: in response to receiving the first message comprising the QoS monitoring request, determine whether a RAN serving the terminal device does not support the QoS monitoring; in accordance with a determination that the RAN does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and in accordance with a determination that the RAN supports the QoS monitoring, transmit, to a third network device in the RAN, a QoS monitoring request comprising a set of parameters for the QoS monitoring, and receive, from the third network device, a QoS monitoring response comprising a result of the QoS monitoring, and transmit, to the second network device, the result of the QoS monitoring.

In some embodiments, the information about the RAN QoS monitoring capability is preconfigured at the first network device or obtained by the first network device from a management device.

In some embodiments, the first network device is further caused to: receive, from a Policy Control Function (PCF) device, a third message comprising a subscription for the RAN QoS monitoring capability; and in response to a change of the RAN QoS monitoring capability, transmit, to the PCF device, updated information about the RAN QoS monitoring capability.

In some embodiments, the first network device implements a Session Management Function (SMF) , and the second network device implements a Policy Control Function (PCF) , and wherein the first network device is further caused to: in response to receiving the first message comprising the QoS monitoring request, determine whether the information about the RAN QoS monitoring capability is available; in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable, transmit the QoS monitoring request to an Access and Mobility Management Function (AMF) device, receive, from the AMF device, a result of the QoS monitoring or a cause for the failure of the QoS monitoring, and transmit, to the second network device, the second message comprising the result of the QoS monitoring or the cause for the failure of the QoS monitoring.

In some embodiments, the first network device is further caused to: in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring, transmit the QoS monitoring request to the AMF device, receive a result of the QoS monitoring from the AMF device, and transmit the result of the QoS monitoring to the second network device.

In some embodiments, the first network device implements a Policy Control Function (PCF) , and the second network device implements an Application Function (AF) , and wherein the first network device is further caused to: in response to receiving the first message comprising the QoS monitoring request, determine whether the information about the RAN QoS monitoring capability is available; in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable, transmit the QoS monitoring request to a Session Management Function (SMF) device, receive, from the SMF device, a result of the QoS monitoring or a cause for the failure of the QoS monitoring, and transmit, to the second network device, the second message comprising the result of the QoS monitoring or the cause for the failure of the QoS monitoring.

In some embodiments, the first network device is further caused to: in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring, transmit the QoS monitoring request to the SMF device, receive a result of the QoS monitoring from the SMF device, and transmit the result of the QoS monitoring to the second network device.

In some embodiments, the first network device is further caused to: transmit, to an Access and Mobility Management Function (AMF) device, a third message comprising a subscription for the RAN QoS monitoring capability; and receive, from the AMF device, updated information about the RAN QoS monitoring capability.

In some embodiments, the cause for the failure of the QoS monitoring indicates that the RAN does not support the QoS monitoring.

In an aspect, it is proposed a second network device comprising: a processor configured to cause the second network device to: transmit, to a first network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for the RAN QoS monitoring capability; and receive, from the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of: a cause for a failure of the QoS monitoring, information about the RAN QoS monitoring capability, or updated information about the RAN QoS monitoring capability.

In some embodiments, the subscription for the RAN QoS monitoring capability is transmitted to the first network device, and wherein the second network device is further caused to: receive, from the first network device, updated information about the RAN QoS monitoring capability.

In some embodiments, the first network device implements an Access and Mobility Management Function (AMF) , and the second network device implements a Session Management Function (SMF) , and wherein the second network device is further caused to: in response to receiving the QoS monitoring request from a Policy Control Function (PCF) device, transmits, to the first network device, the first message comprising the QoS monitoring request; and receive the second message from the first network device, wherein the second message comprises the cause for the failure of the QoS monitoring and a RAN serving the terminal device does not support the QoS monitoring, or wherein the second message comprises a result of the QoS monitoring and the RAN supports the QoS monitoring.

In some embodiments, the first network device implements a Session Management Function (SMF) , and the second network device implements a Policy Control Function (PCF) , and wherein the first network device is further caused to: in response to receiving the QoS monitoring request from an Application Function (AF) device, transmit the first message comprising the QoS monitoring request to the first network device; and receive, from the first network device, the second message comprising a result of the QoS monitoring or the cause for the failure of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is unavailable to the first network device.

In some embodiments, the second network device is further caused to: receive, from the first network device, the second message comprising the cause for the failure of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring; or receive, from the first network device, the second message comprising the result of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring.

In some embodiments, the first network device implements a Policy Control Function (PCF) , and the second network device implements an Application Function (AF) , and wherein the second network device is further caused to: determine whether the information about the RAN QoS monitoring capability is available; in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable, transmit the first message comprising the QoS monitoring request to the first network device; and in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device supports the QoS monitoring, transmit the first message comprising the QoS monitoring request to the first network device.

In some embodiments, the second network device is further caused to: receive, from the first network device, the second message comprising the cause for the failure of the QoS monitoring, wherein the RAN does not support the QoS monitoring; or receive, from the first network device, the second message comprising a result of the QoS monitoring, wherein the RAN supports the QoS monitoring.

In an aspect, a first network device comprises: at least one processor; and at least one memory coupled to the at least one processor and storing instructions thereon, the instructions, when executed by the at least one processor, causing the device to perform the method implemented by the first network device discussed above.

In an aspect, a second network device comprises: at least one processor; and at least one memory coupled to the at least one processor and storing instructions thereon, the instructions, when executed by the at least one processor, causing the device to perform the method implemented by the second network device discussed above.

In an aspect, a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the first network device discussed above.

In an aspect, a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the second network device discussed above.

In an aspect, a computer program comprising instructions, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the first network device discussed above.

In an aspect, a computer program comprising instructions, the instructions, when executed on at least one processor, causing the at least one processor to perform the method implemented by the second network device discussed above.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to FIGS. 1 to 10. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

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 present disclosure, 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.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A first network device comprising:

a processor configured to cause the first network device to:

receive, from a second network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for a RAN QoS monitoring capability; and

transmit, to the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of:

a cause for a failure of the QoS monitoring,

information about the RAN QoS monitoring capability, or

updated information about the RAN QoS monitoring capability.
The device of claim 1, wherein the first network device is further caused to:

in response to receiving the subscription for the QoS monitoring capability and in response to a change of the RAN QoS monitoring capability, transmit, to the second network device, the updated information about the RAN QoS monitoring capability.
The device of claim 1 or 2, wherein the first network device implements an Access and Mobility Management Function (AMF) , and the second network device implements a Session Management Function (SMF) , and wherein the first network device is further caused to:

in response to receiving the first message comprising the QoS monitoring request, determine whether a RAN serving the terminal device does not support the QoS monitoring;

in accordance with a determination that the RAN does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and

in accordance with a determination that the RAN supports the QoS monitoring,

transmit, to a third network device in the RAN, a QoS monitoring request comprising a set of parameters for the QoS monitoring, and

receive, from the third network device, a QoS monitoring response comprising a result of the QoS monitoring, and

transmit, to the second network device, the result of the QoS monitoring.
The device of claim 3, wherein the information about the RAN QoS monitoring capability is preconfigured at the first network device or obtained by the first network device from a management device.
The device of claim 3 or 4, wherein the first network device is further caused to:

receive, from a Policy Control Function (PCF) device, a third message comprising a subscription for the RAN QoS monitoring capability; and

in response to a change of the RAN QoS monitoring capability, transmit, to the PCF device, updated information about the RAN QoS monitoring capability.
The device of claim 1 or 2, wherein the first network device implements a Session Management Function (SMF) , and the second network device implements a Policy Control Function (PCF) , and wherein the first network device is further caused to:

in response to receiving the first message comprising the QoS monitoring request, determine whether the information about the RAN QoS monitoring capability is available;

in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable,

transmit the QoS monitoring request to an Access and Mobility Management Function (AMF) device,

receive, from the AMF device, a result of the QoS monitoring or a cause for the failure of the QoS monitoring, and

transmit, to the second network device, the second message comprising the result of the QoS monitoring or the cause for the failure of the QoS monitoring.
The device of claim 6, wherein the first network device is further caused to:

in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and

in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring,

transmit the QoS monitoring request to the AMF device,

receive a result of the QoS monitoring from the AMF device, and

transmit the result of the QoS monitoring to the second network device.
The device of claim 1 or 2, wherein the first network device implements a Policy Control Function (PCF) , and the second network device implements an Application Function (AF) , and wherein the first network device is further caused to:

in response to receiving the first message comprising the QoS monitoring request, determine whether the information about the RAN QoS monitoring capability is available;

in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable,

transmit the QoS monitoring request to a Session Management Function (SMF) device,

receive, from the SMF device, a result of the QoS monitoring or a cause for the failure of the QoS monitoring, and

transmit, to the second network device, the second message comprising the result of the QoS monitoring or the cause for the failure of the QoS monitoring.
The device of claim 8, wherein the first network device is further caused to:

in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring, transmit, to the second network device, the second message comprising the cause for the failure of the QoS monitoring; and

in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring,

transmit the QoS monitoring request to the SMF device,

receive a result of the QoS monitoring from the SMF device, and

transmit the result of the QoS monitoring to the second network device.
The device of claim 8 or 9, wherein the first network device is further caused to:

transmit, to an Access and Mobility Management Function (AMF) device, a third message comprising a subscription for the RAN QoS monitoring capability; and

receive, from the AMF device, updated information about the RAN QoS monitoring capability.
The device of any of claims 1 to 10, wherein the cause for the failure of the QoS monitoring indicates that the RAN does not support the QoS monitoring.
A second network device comprising:

a processor configured to cause the second network device to:

transmit, to a first network device, a first message regarding a Quality of Service (QoS) monitoring on a terminal device, the first message comprising at least one of: a QoS monitoring request, or a subscription for a RAN QoS monitoring capability; and

receive, from the second network device, a second message indicating the RAN QoS monitoring capability, the second message comprising at least one of:

a cause for a failure of the QoS monitoring,

information about the RAN QoS monitoring capability, or

updated information about the RAN QoS monitoring capability.
The device of claim 12, wherein the subscription for the RAN QoS monitoring capability is transmitted to the first network device, and wherein the second network device is further caused to:

receive, from the first network device, updated information about the RAN QoS monitoring capability.
The device of claim 12 or 13, wherein the first network device implements an Access and Mobility Management Function (AMF) , and the second network device implements a Session Management Function (SMF) , and wherein the second network device is further caused to:

in response to receiving the QoS monitoring request from a Policy Control Function (PCF) device, transmits, to the first network device, the first message comprising the QoS monitoring request; and

receive the second message from the first network device,

wherein the second message comprises the cause for the failure of the QoS monitoring and a RAN serving the terminal device does not support the QoS monitoring, or

wherein the second message comprises a result of the QoS monitoring and the RAN supports the QoS monitoring.
The device of claim 14, wherein the information about the RAN QoS monitoring capability is preconfigured at the first network device or obtained by the first network device from a management device.
The device of claim 11 or 12, wherein the first network device implements a Session Management Function (SMF) , and the second network device implements a Policy Control Function (PCF) , and wherein the first network device is further caused to:

in response to receiving the QoS monitoring request from an Application Function (AF) device, transmit the first message comprising the QoS monitoring request to the first network device; and

receive, from the first network device, the second message comprising a result of the QoS monitoring or the cause for the failure of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is unavailable to the first network device.
The device of claim 16, wherein the second network device is further caused to:

receive, from the first network device, the second message comprising the cause for the failure of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device does not support the QoS monitoring; or

receive, from the first network device, the second message comprising the result of the QoS monitoring, wherein the information about the RAN QoS monitoring capability is available and the information indicates that the RAN supports the QoS monitoring.
The device of claim 12 or 13, wherein the first network device implements a Policy Control Function (PCF) , and the second network device implements an Application Function (AF) , and wherein the second network device is further caused to:

determine whether the information about the RAN QoS monitoring capability is available;

in accordance with a determination that the information about the RAN QoS monitoring capability is unavailable, transmit the first message comprising the QoS monitoring request to the first network device; and

in accordance with a determination that the information about the RAN QoS monitoring capability is available and the information indicates that a RAN serving the terminal device supports the QoS monitoring, transmit the first message comprising the QoS monitoring request to the first network device.
The device of claim 18, wherein the second network device is further caused to:

receive, from the first network device, the second message comprising the cause for the failure of the QoS monitoring, wherein the RAN does not support the QoS monitoring; or

receive, from the first network device, the second message comprising a result of the QoS monitoring, wherein the RAN supports the QoS monitoring.
The device of any of claims 12 to 19, wherein the cause for the failure of the QoS monitoring indicates that the RAN does not support the QoS monitoring.