Methods, apparatus and systems determined by application examples

Abstract

This application provides a method, apparatus, and system for determining application instances. The method includes: a first network element acquiring the location information of a terminal, determining at least one first MEC application instance based on the location information of the terminal, and sending the address information of at least one first MEC application instance to the terminal, thereby reducing the message transmission delay between the MEC application instance and the terminal and improving the quality of service.

Description

[0001] This application claims priority to two Chinese patent applications filed with the State Intellectual Property Office on December 31, 2019, application number 201911413716.3, entitled "Method, Apparatus and System for Determining Application Examples", and on January 6, 2020, application number 202010011314.7, entitled "Method, Apparatus and System for Determining Application Examples", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to methods, apparatus and systems for determining application examples. Background Technology

[0003] Multi-access edge computing (MEC) provides cloud computing capabilities to users at the edge of the operator's network, close to the mobile user's location. Users can leverage this capability to deploy applications at the network edge. Deploying cloud computing capabilities at the network edge gives telecommunications services the advantages of high performance, low latency, and high bandwidth, accelerating the distribution and download of various content, services, and applications within the network, and providing consumers with a higher quality network experience.

[0004] The European Telecommunications Standards Institute (ETSI) defines a reference architecture for MEC in its specification ETSI GS MEC 003, such as... Figure 1As shown, this architecture mainly consists of two parts: the MEC Host and the MEC Management System. The MEC Host includes the MEC Platform, Virtualization Infrastructure, and MEC Apps. The Virtualization Infrastructure provides virtualized computing, storage, and network resources for MEC Apps, which are deployed on the MEC Host as virtual machines or containers. The MEC Platform primarily includes service registration and discovery functions, as well as some public services such as a Domain Name System (DNS) server or DNS proxy service. The MEC Management System includes a Multi-access Edge Orchestrator, a MEC Platform Manager, and a Virtualization Infrastructure Manager (VIM). The Multi-access Edge Orchestrator maintains an overall view of all mobile edge hosts, available resources, and available MEC services in the MEC system, triggering application instantiation and termination. The MEC Platform Manager manages the MEC Platform, the lifecycle of mobile MEC Apps, and application flow rules and DNS rules. The VIM manages the virtualization resources required by MEC Apps. The Userapp Lifecycle Management proxy allows device apps to request the MEC system to instantiate or terminate MEC applications.

[0005] How to provide the best MEC application instances for the terminal is a problem that needs to be solved. Summary of the Invention

[0006] This application provides a method, apparatus, and system for determining application instances, used to determine the optimal MEC application instance for a terminal.

[0007] In a first aspect, a method for determining an application instance is provided, comprising: a first network element acquiring the location information of a terminal; the first network element determining at least one first MEC application instance based on the location information of the terminal; and the first network element sending the address information of the at least one first MEC application instance to the terminal.

[0008] Based on the above scheme, when a terminal requests an MEC application instance, the first network element determines the MEC application instance with the best distance from the terminal based on the location information obtained by the terminal and the correspondence between the maintained location information and the MEC application instance. This reduces the message transmission delay between the MEC application instance and the terminal and improves the quality of service.

[0009] In one possible implementation, the first network element receives a first message sent by the terminal, the first message including the location information of the terminal.

[0010] In one possible implementation, the first network element receives a second message sent by a core network control plane function network element, the second message including the location information of the terminal.

[0011] In one possible implementation, the first network element stores address information of at least one MEC application instance and location information of the at least one MEC application instance. The first network element determines at least one first MEC application instance based on the location information of the terminal, including: the first network element determines the at least one first MEC application instance from the at least one MEC application instance based on the location information of the terminal and the location information of the at least one MEC application instance.

[0012] Secondly, a method for determining application instances is provided, comprising: a control plane function network element sending a first notification message to a first network element, the first notification message being used to notify the first network element that the user plane path of the terminal has changed; the first network element obtaining the location information of the terminal; the first network element determining at least one first MEC application instance based on the location information of the terminal; and the first network element sending the address information of the at least one first MEC application instance to the terminal.

[0013] Based on the above scheme, when the terminal changes due to the UPF, the current MEC application instance may no longer be optimal. The first network element determines the optimal application instance after switching to the new UPF by using the terminal's location information (destination user plane location), thereby reducing the packet transmission latency between the MEC application instance and the terminal and improving the quality of service.

[0014] In one possible implementation, the first network element obtains the location information of the terminal, including: the first network element receives the first notification information, the first notification information including the location information of the terminal, and the location information of the terminal being the location information of the target user plane function (UPF).

[0015] In one possible implementation, the method further includes: the first network element receiving an MEC application instance change subscription request message sent by the terminal.

[0016] Thirdly, a method for determining application instances is provided, comprising: a first network element obtaining information of at least one first EDN from a session management network element, wherein the at least one first EDN is determined based on the location information of a terminal; the first network element determining at least one first MEC application instance from the at least one first EDN; and the first network element sending the address information of the at least one first MEC application instance to the terminal. The method provided in this third aspect, when a terminal requests an MEC application instance, allows the first network element to request information of at least one first EDN from the session management network element (SMF) to determine at least one first MEC application instance, thereby reducing message transmission latency between the MEC application instance and the terminal and improving service quality.

[0017] In one possible implementation, the first network element obtains information about at least one first EDN from the session management network element, including: the first network element sending a third message to the session management network element, the third message being used to request at least one EDN, the at least one EDN deploying the MEC application instance requested by the terminal; and the first network element receiving the information about the at least one first EDN from the session management network element.

[0018] In one possible implementation, the third message includes information about a candidate EDN, which is determined by the first network element based on the location information of the terminal and the EDN information stored in the first network element.

[0019] In one possible implementation, the third message includes the location information of the terminal.

[0020] In one possible implementation, the information of the first EDN includes: the data network application identifier (DNAI) of the first EDN.

[0021] In one possible implementation, the method further includes: the first network element sending the address information of the EES associated with the at least one first MEC application instance to the terminal, wherein the EES associated with the at least one first MEC application instance is deployed in the at least one first EDN.

[0022] In one possible implementation, the information from the first EDN is used to indicate the communication performance of the communication path between the terminal and the first EDN.

[0023] In one possible implementation, the information of the first EDN further includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0024] In one possible implementation, the method further includes: the first network element sending priority information of the at least one first MEC application instance to the terminal.

[0025] Fourthly, a method for determining an EES is provided, comprising: a first network element obtaining information about at least one first EDN from a session management network element, wherein the at least one first EDN is determined based on the location information of a terminal; the first network element determining at least one first EES from the at least one first EDN; and the first network element sending the address information of the at least one first EES to the terminal. The method provided in the fourth aspect, when a terminal requests an EES, allows the first network element to request information about at least one first EDN from the session management network element (SMF), thereby determining at least one first EES, thus reducing the message transmission latency between the MEC application instance managed by the EES and the terminal, and improving the quality of service.

[0026] In one possible implementation, the first network element obtains information about at least one first EDN from the session management network element, including: the first network element sending a third message to the session management network element, the third message being used to request at least one EDN, the at least one EDN deploying the EES requested by the terminal; and the first network element receiving the information about the at least one first EDN from the session management network element.

[0027] In one possible implementation, the third message includes information about a candidate EDN, which is determined by the first network element based on the location information of the terminal and the EDN information stored in the first network element.

[0028] In one possible implementation, the third message includes the location information of the terminal.

[0029] In one possible implementation, the information of the first EDN includes: the data network application identifier (DNAI) of the first EDN.

[0030] In one possible implementation, the information from the first EDN is used to indicate the communication performance of the communication path between the terminal and the first EDN.

[0031] In one possible implementation, the information of the first EDN further includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0032] In one possible implementation, the method further includes: the first network element sending priority information of the at least one first EES to the terminal.

[0033] Fifthly, a communication method is provided, comprising: a session management network element receiving a third message from a first network element, the third message being used to request at least one EDN; the at least one EDN deploying a MEC application instance requested by a terminal, or the at least one EDN deploying an EES requested by the terminal; the session management network element sending information about at least one first EDN to the first network element according to the third message; when the at least one EDN deploys the MEC application instance requested by the terminal, the first EDN is the EDN deploying the MEC application instance requested by the terminal; when the at least one EDN deploys the EES requested by the terminal, the first EDN is the EDN deploying the EES requested by the terminal. The communication method provided in the fifth aspect, when a terminal requests a MEC application instance, the first network element requests information about at least one first EDN from the SMF, thereby determining at least one first MEC application instance, thereby reducing the message transmission latency between the MEC application instance and the terminal and improving the quality of service. When a terminal requests an EES, the first network element requests information about at least one first EDN from the SMF, thereby determining at least one first EES. This reduces the message transmission latency between MEC application instances managed by the EES and the terminal, and improves the quality of service.

[0034] In one possible implementation, the at least one first EDN is determined based on the location information of the terminal and the information of at least one EDN obtained by the session management network element.

[0035] In one possible implementation, the at least one first EDN is determined based on the location information of the terminal and information of alternative EDNs, the information of the alternative EDNs being carried in the third message.

[0036] In one possible implementation, the location information of the terminal is carried in the third message.

[0037] In one possible implementation, the information of the first EDN includes: the data network application identifier (DNAI) of the first EDN.

[0038] In one possible implementation, the information from the first EDN is used to indicate the communication performance of the communication path between the terminal and the first EDN.

[0039] In one possible implementation, the information of the first EDN further includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0040] Sixthly, a signal transmission method is provided, comprising: a terminal sending a first message, the first message including the location information of the terminal; or, the terminal sending an MEC application instance change subscription request.

[0041] In a seventh aspect, a method for determining an EES is provided, comprising: a first network element obtaining information of at least one first EDN from a second network element, wherein the at least one first EDN is determined based on at least one of the terminal's location information or the terminal's service information, and the second network element is a first session management network element or a NEF; the first network element determining at least one first EES based on the information of the at least one first EDN; and the first network element sending the address information of the at least one first EES to the terminal.

[0042] In one possible implementation, the first network element obtains information about at least one first EDN from the second network element, including: the first network element sending a third message to the second network element, the third message including at least one of information for determining the location of the terminal or service information of the terminal; the first network element receiving the information about the at least one first EDN from the second network element, wherein the first EDN matches at least one of the location information of the terminal or the service information of the terminal.

[0043] In one possible implementation, the information of the first EDN includes at least one DNAI of the first EDN.

[0044] In one possible implementation, the information of the first EDN further includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0045] In one possible implementation, the method further includes: the first network element sending priority information of the at least one first EES to the terminal.

[0046] Eighthly, a communication method is provided, comprising: a second network element receiving a third message from a first network element, the third message including at least one of information for determining the location of a terminal or service information of the terminal, the second network element being a first session management network element or a NEF; the second network element sending at least one first EDN to the first network element according to the third message, the first EDN matching at least one of the location information of the terminal or the service information of the terminal.

[0047] In one possible implementation, the second network element sends at least one first EDN information to the first network element according to the third message, including: the second network element determining a second session management network element based on the location information of the terminal; the second network element sending a request message to the second session management network element, the request message including at least one of location information or service information, the location information including the location information of the terminal, and the service information including the service information of the terminal; the second network element receiving the at least one first EDN information from the second session management network element; and the second network element sending the at least one first EDN information to the first network element.

[0048] In one possible implementation, the second network element is the NEF. The second network element sends at least one first EDN information to the first network element according to the third message, including: the second network element determining the at least one first EDN information based on the terminal's location information and a first correspondence, wherein the first correspondence includes a correspondence between location area information and EDN information; or, the second network element determining the at least one first EDN information based on the terminal's service information and a second correspondence, wherein the second correspondence includes a correspondence between service information and EDN information; or, the second network element determining the at least one first EDN information based on the terminal's location information, service information, and a third correspondence, wherein the third correspondence includes a correspondence between location area information, EDN information, and service information; and the second network element sending the at least one first EDN information to the first network element.

[0049] In one possible implementation, the information of the first EDN includes at least one DNAI of the first EDN.

[0050] In one possible implementation, the information of the first EDN further includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0051] A ninth aspect provides a communication method, comprising: a second session management network element receiving a request message from a second network element, the request message including at least one of location information and service information, the location information including location information of a terminal, and the service information including service information of the terminal, the second network element being a first session management network element or a NEF; wherein, if the request message includes the location information, the second session management network element determines information of at least one first EDN based on the location information and a first correspondence, the first correspondence including a correspondence between location area information and EDN information; or, if the request message includes the service information, the second session management network element determines information of at least one first EDN based on the service information and a second correspondence, the second correspondence including a correspondence between service information and EDN information; or, if the request message includes the location information and the service information, the second session management network element determines information of at least one first EDN based on the location information, the service information, and a third correspondence, the third correspondence including a correspondence between location area information, EDN information, and service information; and the second session management network element sending the information of at least one first EDN to the second network element.

[0052] In a tenth aspect, a communication device is provided, comprising: a functional unit for performing any one of the methods provided in any one of the first to ninth aspects, wherein the action performed by the functional unit is implemented by hardware or by hardware executing corresponding software.

[0053] Eleventhly, a communication device is provided, including a processor and a memory; the memory is used to store computer execution instructions, and when the device is running, the processor executes the computer execution instructions stored in the memory to cause the device to perform any one of the methods provided by any one of the first to ninth aspects above.

[0054] In a twelfth aspect, a terminal device is provided for sending a first message, the first message including the location information; or for sending an MEC application instance change subscription request.

[0055] In a thirteenth aspect, a communication apparatus is provided, comprising units or means for performing various steps in any method provided by any of the first to ninth aspects.

[0056] In a fourteenth aspect, a communication device is provided, comprising a processor and an interface circuit, the processor being configured to communicate with other devices via the interface circuit and to execute any one of the methods provided in any of the first to ninth aspects. The processor may include one or more devices.

[0057] In a fifteenth aspect, a communication device is provided, comprising a processor for connection to a memory, for invoking a program stored in the memory to execute any one of the methods provided in any of the first to ninth aspects. The memory may be located within or outside the device. The processor may include one or more processors.

[0058] In a sixteenth aspect, a computer-readable storage medium is provided, wherein instructions are stored therein, which, when executed on a computer, cause a processor to perform any one of the methods provided in any one of the first to ninth aspects.

[0059] In a seventeenth aspect, a computer program product including instructions is provided, which, when run on a computer, causes the computer to perform any one of the methods provided in any one of the first to ninth aspects.

[0060] Eighteenth aspect, a chip system is provided, comprising: a processor for executing any one of the methods provided in any one of the first to ninth aspects.

[0061] In a nineteenth aspect, a communication system is provided, comprising: a control plane function network element and a first network element; the control plane function network element is configured to send a first notification message to the first network element, the first notification message being configured to notify the first network element that the user plane path of a terminal has changed; the first network element is configured to obtain the location information of the terminal and determine at least one first MEC application instance based on the location information of the terminal; the first network element is further configured to send the address information of the at least one first MEC application instance to the terminal.

[0062] In a twentieth aspect, a communication system is provided, comprising: any one or more network elements involved in the first to ninth aspects. Attached Figure Description

[0063] Figure 1 This is a schematic diagram of the architecture of an MEC system;

[0064] Figure 2 This is a schematic diagram of a 5G network architecture based on a service-oriented architecture.

[0065] Figure 3 This is a schematic diagram of the architecture of an MEC system;

[0066] Figure 3A This is a schematic diagram of another MEC system architecture;

[0067] Figure 3B This is a schematic diagram of another MEC system architecture;

[0068] Figure 3C This is a schematic diagram of another MEC system architecture;

[0069] Figure 4 This is a diagram illustrating the relationship between terminal locations and MEC application instance locations.

[0070] Figure 5 A flowchart illustrating a method for determining an application instance as provided in an embodiment of this application;

[0071] Figure 6 A flowchart illustrating another application example determination method provided in this application embodiment;

[0072] Figure 6A A flowchart illustrating another application example determination method provided in this application embodiment;

[0073] Figure 6B A flowchart illustrating a method for EES determination provided in an embodiment of this application;

[0074] Figure 6C A schematic diagram showing the locations of an EES and an EDN CS provided in an embodiment of this application;

[0075] Figure 6D A flowchart illustrating a method for EES determination provided in an embodiment of this application;

[0076] Figure 6E A flowchart illustrating a method for obtaining EDN information provided in an embodiment of this application;

[0077] Figure 6F A flowchart illustrating another method for obtaining EDN information provided in an embodiment of this application;

[0078] Figure 6G A schematic diagram illustrating the correspondence between DNAI and EDN provided in an embodiment of this application;

[0079] Figure 7 A schematic diagram of a communication device provided in an embodiment of this application;

[0080] Figure 8 A schematic diagram of another communication device provided in the embodiments of this application;

[0081] Figure 8A A schematic diagram of another communication device provided in the embodiments of this application;

[0082] Figure 8B A schematic diagram of another communication device provided in the embodiments of this application;

[0083] Figure 9This is a schematic diagram of another communication device provided in an embodiment of this application. Detailed Implementation

[0084] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings. The specific operating methods in the method embodiments can also be applied to the device embodiments or system embodiments. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more.

[0085] like Figure 2 The diagram shown is a schematic of the fifth-generation (5G) network architecture based on a service-oriented architecture. Figure 2 The 5G network architecture shown can include three parts, namely the terminal part (i.e. Figure 2 The network consists of the UE (User Equipment), data network (DN), and carrier network. The functions of some of these network elements are briefly described below.

[0086] The operator network may include one or more of the following network elements: authentication server function (AUSF) network elements, network exposure function (NEF) network elements, policy control function (PCF) network elements, unified data management (UDM) network elements, unified data repository (UDR) network elements, network repository function (NRF) network elements, application function (AF) network elements, access and mobility management function (AMF) network elements, session management function (SMF) network elements, radio access network (RAN) network elements, and user plane function (UPF) network elements. The portion of the operator network excluding the radio access network can be referred to as the core network portion.

[0087] A terminal is a device with wireless transceiver capabilities that can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; it can also be deployed on water (such as on ships); and it can be deployed in the air (such as on airplanes, balloons, and satellites). Terminals can also be called user equipment (UE), terminal device, access terminal, user unit, user station, mobile station, remote station, remote terminal, mobile device, user terminal, wireless communication equipment, user agent, or user device. Terminals can be mobile phones, tablets, computers with wireless transceiver capabilities, virtual reality (VR) terminals, augmented reality (AR) terminals, wireless terminals in industrial control, wireless terminals in self-driving vehicles, wireless terminals in remote medical care, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, etc.

[0088] The aforementioned terminals can establish connections with the operator's network through interfaces provided by the operator's network (such as N1), and use data and / or voice services provided by the operator's network. The terminals can also access the DN (Network Provider) through the operator's network, and use operator services deployed on the DN, and / or services provided by third parties. These third parties can be service providers outside of the operator's network and the terminal, and can provide the terminal with other data and / or voice services. The specific form of these third parties can be determined based on the actual application scenario and is not limited here.

[0089] RAN (Access Network Controller) is a subnetwork of a carrier network, serving as the implementation system between service nodes and terminals within the carrier network. For a terminal to access the carrier network, it first passes through the RAN, and then connects to service nodes within the carrier network via the RAN. RAN equipment is a device that provides wireless communication capabilities to terminals; RAN equipment is also known as access network equipment. RAN equipment includes, but is not limited to: next-generation base stations (g node B, gNB) in 5G, evolved node B (eNB), radio network controller (RNC), node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (e.g., home-evolved node B, or home node B, HNB), baseband unit (BBU), transmitting and receiving point (TRP), transmitting point (TP), mobile switching center, etc.

[0090] AMF network elements are responsible for user mobility management, including mobility state management, assigning temporary user identities, authenticating and authorizing users, etc.

[0091] The SMF network element has functions such as session management, execution of PCF-issued control policies, selection of UPF, allocation of terminal Internet Protocol (IP) addresses, establishment, modification and release of bearers, and Quality of Service (QoS) control.

[0092] UPF network elements support functions such as interconnecting Protocol Data Unit (PDU) sessions with data networks, packet routing and forwarding, and packet inspection.

[0093] UDM network elements are mainly responsible for managing contract data, user access authorization, and other functions.

[0094] The User Data Controller (UDC) stores and retrieves contract data, policy data, and public architecture data. It provides relevant data to the User Data Manager (UDM), PCF, and NEF. The UDR must have different data access authentication mechanisms for different data types, such as contract data and policy data, to ensure data access security. The UDR must be able to return a failure response with an appropriate reason value for unauthorized service operations or data access requests.

[0095] The NEF (Network Element Framework) primarily supports network capability exposure, enabling the external release of network capabilities and services. 3GPP (3rd Generation Partnership Project) network functions (NFs) publish functions and events to other NFs through the NEF. The capabilities and events exposed by NFs can be securely exposed to third-party applications. The NEF uses a standardized interface (Nudr) of the Unified Data Repository (UDR) to store and retrieve structured data. It also translates the exchange information between AFs (Analog Functions) and internal network functions.

[0096] An Application Layer (AF) element is used to provide certain application-layer services to terminals. When providing services to terminals, the AF has requirements for QoS and charging policies and needs to notify the network. At the same time, the AF also needs application-related information from the core network.

[0097] The PCF network element is primarily responsible for policy control functions such as billing at the session and service flow levels, QoS bandwidth assurance, mobility management, and terminal policy decisions. In this architecture, the PCFs connected to the AMF and SMF correspond to the AM PCF (PCF for Access and Mobility Control) and SM PCF (PCF for Session Management), respectively, but may not be the same PCF entity in actual deployment scenarios.

[0098] NRF network elements can be used to provide network element discovery functionality, providing network element information corresponding to the network element type based on requests from other network elements. NRF also provides network element management services, such as network element registration, updates, deregistration, and network element status subscription and push.

[0099] AUSF network element: mainly responsible for authenticating users to determine whether to allow users or devices to access the network.

[0100] A Domain Provider (DN) is a network located outside the carrier's network. A carrier's network can connect to multiple DNs, and various services can be deployed on a DN, providing data and / or voice services to terminals. For example, a DN might be the private network of a smart factory. Sensors installed in the workshop can act as terminals, and a control server for these sensors is deployed within the DN. The control server provides services to the sensors. Sensors can communicate with the control server, receive instructions from it, and transmit the collected sensor data back to the control server accordingly. Another example is a DN serving as an internal office network for a company. Employees' mobile phones or computers can act as terminals, accessing information and data resources on the company's internal office network.

[0101] Figure 2Nausf, Nnef, Npcf, Nudm, Naf, Namf, Nsmf, N1, N2, N3, N4, and N6 are interface sequence numbers. The meanings of these interface sequence numbers can be found in the definitions in the 3GPP standard protocols, and are not limited here.

[0102] It is understood that the aforementioned network element or function can be a network component in a hardware device, a software function running on dedicated hardware, or a virtualized function instantiated on a platform (e.g., a cloud platform). Optionally, the aforementioned network element or function can be implemented by one device, multiple devices working together, or a functional module within a single device; this application embodiment does not specifically limit this.

[0103] In the embodiments of this application, the mobility management network element, session management network element, policy control network element, application function network element, access network device, network access function network element, and user plane network element can be respectively... Figure 2 The AMF, SMF, PCF, AF, RAN, NEF, and UPF mentioned here can also refer to network elements in future communications such as 6th generation (6G) networks that have the functions of the aforementioned AMF, SMF, PCF, AF, RAN, NEF, and UPF. This application embodiment does not limit this. For ease of explanation, this application embodiment uses mobility management network elements, session management network elements, policy control network elements, application function network elements, access network equipment, network open function network elements, and user plane network elements as examples to illustrate the aforementioned AMF, SMF, PCF, AF, RAN, NEF, and UPF, respectively.

[0104] like Figure 3 The diagram illustrates the architecture of an MEC system provided in an embodiment of this application. The MEC server is deployed between the radio access network and the core network. The MEC server is a server that has deployed the MEC platform and is managed by the MEC platform. Furthermore, the MEC server can connect to cloud data centers and other networks, such as enterprise networks. Thus, the MEC server utilizes the radio access network to provide services and cloud computing functions to terminals in their vicinity. In this embodiment, the MEC server can be established by an operator, enterprise, virtual operator, or service provider. The MEC server can also integrate... Figure 2 UPF in the middle.

[0105] The method provided in this application embodiment can be applied to the following two MEC architectures.

[0106] The first type: The reference architecture of MEC defined by ETSI in its specification ETSI GS MEC 003, which can be found in [reference needed]. Figure 1 ,about Figure 1 For a detailed description, please refer to the background technology section, which will not be repeated here.

[0107] The second type: as defined by the 3GPP SA6 working group, such as... Figure 3A or Figure 3B The reference architecture of MEC is shown. Among them, Figure 3B and Figure 3A The only difference is that, Figure 3B The system integrates the functionality of the edge enabler client (EEC) and the edge data network configuration client (EDN CC) into a single enabler client that combines the features of both EDN CC and EEC. Figure 3B (Note: This refers to enabling the client). The following is about... Figure 3A and Figure 3B This section provides a brief introduction to the various functional modules and the interfaces between them.

[0108] Edge Data Network (EDN): An EDN provides edge computing services to terminals and can include computing, storage, networking, communication, and routing functions. It typically includes an edge computing management platform (e.g., an edge enabler server (EES) hereinafter referred to as an edge enabler server) and edge application instances (e.g., an edge application server (EAS)). In one understanding, an EDN can be a local data network (i.e., a local DN), representing the access point of the data network physically closest to the user's attachment point (i.e., the access network equipment (e.g., a base station) to which the terminal connects). A data network can have multiple local data networks, which can be identified using a data network name (DNN) and / or a data network application identifier (DNAI). The DNAI identifies the location of the local data network. In another understanding, an EDN is a peer-to-peer concept of a central cloud; that is, an EDN can be understood as a local data center that can support multiple local data networks. Data centers can also be identified using DNAIs.

[0109] EAS: EAS is used to provide application services with edge computing characteristics to application clients. Specifically, it refers to an instance of a server application (e.g., social media software, augmented reality (AR), virtual reality (VR)) deployed and running on an EDN. A MEC application can deploy one or more EAS in one or more EDNs. EAS deployed and running in different EDNs can be considered different EASs. They can share a domain name, use the same IP address, or use different IP addresses. EAS can also be referred to as edge application, application instance, edge application instance, MEC application, MEC application instance, EAS function, etc.

[0110] Application Client: The application client is used by application users to obtain application services from the application server. The application client is the client program of MEC application on the terminal side. The application client can connect to the application server on the cloud to obtain application services, or it can connect to EAS deployed and running in one or more EDNs to obtain application services.

[0111] EES: EES provides edge computing enabling services for EAS and EEC to better support the deployment of MEC applications at the edge. EES supports EAS registration, terminal authentication and authorization, and DNS functionality providing application server IP address information to terminals. EES is deployed within an EDN. Generally, an EAS registers with an EES, or the management system configures EAS information on an EES. This EES is called the EES associated with the EAS, and the EES controls (or manages) the EAS registered (or configured) on that EES.

[0112] EEC: EEC is the peer entity of EES on the terminal side. EEC is used to register EEC information and application client information with EES, perform security authentication and authorization, obtain EAS IP address from EES, and provide edge computing enabling capabilities to application clients, such as returning the EAS IP address to the application client in the EAS discovery service. EEC can also call the service interfaces provided by EDN CC.

[0113] Edge Data Network Configuration Server (EDNCS): The EDNCS is used to configure EDN information for terminals. For example, it provides terminals with EES information within the EDN. Furthermore, the EDNCS can function as a DNS server, possessing EAS domain names, EAS IP addresses, and information about EES registered with EAS. It can also directly provide EAS information to terminals and interact with the DNS server of MEC applications to obtain application server information. The EDN CS can accept EES queries or EAS queries from the EDN CC and provide the corresponding query results. The EDN CS can accept EES registrations to obtain EAS domain names, EAS IP addresses, and information about EES registered with EAS; this information can also be obtained through configuration.

[0114] EDN CC: EDN CC is the peer entity of EDN CS on the endpoint side. EDN CC can obtain EES information from EDN CS. Furthermore, it can also obtain EAS information from EDN CS. EDN CC can also be used to provide edge computing enablement service interfaces to EEC or application clients.

[0115] In this process, application users sign service agreements with MEC application providers to obtain services. Application users communicate with the EAS via an application client on their login terminal. The enabling client (e.g., EEC, EDN CC) is a middleware layer, typically located within the operating system or as middleware between the application client and the operating system. Application clients can obtain edge enabling services from the enabling client using an application programming interface (API).

[0116] Edge-1 (EDGE-1) interface: The interface between EEC and EES, which enables EEC registration, security authentication, EES discovery, and application context migration support.

[0117] Edge-2 (EDGE-2) interface: The interface between EES and 3GPP networks, used for interaction with 3GPP core network elements. It can interface with network elements such as network exposure function (NEF) and policy control function (PCF).

[0118] Edge-3 interface: The interface between EAS and EES, mainly used for EAS to call services provided by EES, such as event subscription and notification, and for EAS to register with EES.

[0119] Edge-4 (EDGE-4) interface: The interface between EDN CS and EDN CC, mainly used by EDN CS to provide EES information to EDN CC, as well as EES discovery, security authorization, etc.

[0120] Edge-5 (EDGE-5) interface: The interface between application clients and EEC, used by application clients to call services provided by EEC, such as EAS discovery, event subscription and notification, context migration, etc.

[0121] Edge-6 (EDGE-6) interface: The interface between EES and EDN CS, mainly used by EES to register EES information with EDN CS, which also includes information of EAS registered on EES.

[0122] Edge-7 (EDGE-7) interface: The interface between EAS and the 3GPP network, used for interaction with 3GPP core network elements, and can interface with network elements such as NEF and PCF.

[0123] Edge-X (EDGE-X) interface: The interface between EEC and EDN CC, which can be used by EDN CC to provide EES information (e.g., identification, address information) to EEC.

[0124] It should be noted that, Figure 3A and Figure 3B The various functional modules and the interfaces between them may have other names, and this application does not impose any restrictions.

[0125] See Figure 3C In practical applications, terminals can communicate with one or more EDNs via mobile communication networks. One or more EESs are deployed within an EDN, and one EES can manage one or more EASs, for example in... Figure 3C In this architecture, EES1 deployed in EDN1 can manage EAS11, EAS12, and EAS13; EES2 deployed in EDN2 can manage EAS21 and EAS22; and EES3 deployed in EDN3 can manage EAS31, EAS32, and EAS33. Each EES can store information about each EAS it manages, including the EAS's identifier (e.g., fully qualified domain name, FQDN) and its address information (e.g., URL or IP address).

[0126] Multiple EES deployed in multiple EDNs can connect to the same EDN CS. The EDN CS can store the address information of each connected EES and the information of the EAS managed by each EES, such as the identifier of the managed EAS, and further, the address information of the managed EAS. For example, in... Figure 3C In the EDN CS, address information of EES1, EES2 and EES3 can be stored, as well as the identifiers and address information of the EAS managed by EES1, EES2 and EES3.

[0127] EAS instances of the same MEC application can be deployed in different EDNs, for example in Figure 3C In the MEC application, the EAS can be EAS11, EAS21, and EAS31; the EAS of MEC application 2 can be EAS12, EAS22, and EAS32; and the EAS of MEC application 3 can be EAS13 and EAS33. To determine whether multiple EASs are different EASs of the same MEC application, this can be done by using the EAS.

[0128] In one interpretation, an EAS registered on an EES can be considered a capability of the EES. For example, if the EAS for MEC application 1 is registered on an EES, it can be assumed that the EES's capabilities include supporting MEC application 1. Since an EAS typically registers with an EES located in the same EDN as that EAS, it can be understood that the EDN optimally located from the terminal (physically closest, with the shortest network connection path, or with the best network connection path) can provide the EES and EAS closest to the terminal.

[0129] In this embodiment of the application, for ease of description, Figure 1 MEC application instances in the architecture shown and Figures 3A to 3C In this context, EAS (Enterprise Application Servers) are collectively referred to as MEC application instances. An MEC application instance is a copy of the same MEC application. MEC application instances are deployed on edge nodes (e.g., EDN). Multiple MEC application instances can also be deployed on the same edge node to achieve load balancing. At any given time, the MEC application installed on a terminal is serviced by a specific MEC application instance on a specific edge node. Generally speaking, the closer the edge node where the MEC application instance is deployed is to the terminal, the lower the packet transmission latency between the MEC application instance and the terminal, and the higher the quality of service. Figure 4As shown, when the terminal is at location 1, MEC application instance 1 located at edge node 1 can be considered the optimal MEC application instance. When the terminal moves to location 2, MEC application instance 2 located at edge node 2 can be considered the optimal MEC application instance. Currently, there is no method to provide the optimal MEC application instance for the terminal's MEC applications.

[0130] based on Figure 2 The network architecture shown, and Figure 1 , Figure 3 , Figure 3A , Figure 3B as well as Figure 3C The MEC architecture shown is Figure 5 This is a schematic diagram of a communication method (also known as a method for determining MEC application instances) provided in an embodiment of this application. Figure 5 The illustrated embodiment uses the discovery process of MEC application instances as an example, including:

[0131] S501, the terminal sends a first message to the first network element, which can be an MEC application instance discovery request message. Correspondingly, the first network element receives the first message from the terminal.

[0132] exist Figure 1 In the MEC architecture shown, the first network element can be a MEC system management plane functional network element, and the specific execution step S501 can be a terminal application.

[0133] exist Figure 3A , Figure 3B and Figure 3C In the MEC architecture shown, the first network element can be either EES or EDN CS. When the first network element is EES, the specific execution step S501 can be performed by the EEC in the terminal; when the first network element is EDN CS, the specific execution step S501 can be performed by the EDN CC or EEC in the terminal.

[0134] In this MEC application instance, the discovery request message originates from the terminal and reaches the first network element through access network devices (e.g., gNB), user plane gateways (e.g., UPF), etc.

[0135] The MEC application instance discovery request message includes one or more of the following information:

[0136] (1) Terminal Identification

[0137] The terminal identifier can be a subscription permanent identifier (SUPI), a generic public subscription identifier (GPSI), a media access control (MAC) address, an IP address, a mobile subscriber international ISDN number (MSISDN), or other identifiers. The terminal identifier can be used to determine the location of the terminal.

[0138] (2) MEC Application Name

[0139] (3) MEC application provider name

[0140] (4) MEC application version

[0141] (5) Identification of MEC applications

[0142] The identification element of a MEC application can include one or more MEC application identifiers. An MEC application identifier can be its FQDN, URL, etc. The MEC application identifier indicates a request to retrieve the address information of the corresponding EAS. For example, if the MEC application identifier is the identifier of MEC application 1, it indicates a request to retrieve the address information of the EAS for MEC application 1. If the first message does not contain an MEC application identifier, it can indicate a request to retrieve the address information of the EAS for all MEC applications.

[0143] (6) Application client information

[0144] The application client information can be used by EAS to identify the terminal. This information can be GPS I, IP address, or an identifier formed by a combination of other characters. The application client information can be used to indicate a request for support for the EAS corresponding to these application clients.

[0145] (7) EEC logo

[0146] The EEC identifier is used to identify the EEC. The EEC identifier can be a GPSI, IP address, or other character combinations used to identify the EEC. The EEC identifier can be used to authenticate and authorize the terminal and obtain the terminal's location information (for example, by determining the terminal's SUPI, GPSI, etc. through the EEC identifier, and thus determining the terminal's location).

[0147] (8) Terminal location information

[0148] The terminal's location information can be any information that can represent the terminal's location, such as the coordinates of the terminal's location, the information of the cell the terminal is in (e.g., the cell identifier), the tracking area information of the tracking area the terminal is in (e.g., the tracking area identifier), or the terminal's data network access point identifier. The terminal's location information can be used to determine the terminal's location.

[0149] S502, the first network element determines at least one first MEC application instance.

[0150] In the specific implementation of step S502, the first network element needs to first obtain the location information of the terminal, and then determine at least one first MEC application instance based on the location information of the terminal.

[0151] Optionally, if the MEC application instance discovery request message received by the first network element contains the terminal's location information, it is considered that the first network element obtains the terminal's location information by receiving the MEC application instance discovery request message. If the MEC application instance discovery request message does not contain the terminal's location information, another optional method is for the first network element to obtain the terminal's location information from a telecom operator's network function, such as a 5G core network control plane function network element (e.g., NEF), based on the terminal identifier. NEF provides an API to expose the capabilities of the telecom network. The first network element sends a location query request including the terminal identifier to the NEF. After receiving the location query request, the NEF calls a core network function, such as the AMF, to obtain the location information. The AMF sends the queried terminal's location information to the caller, i.e., the NEF. The NEF then sends a second message to the first network element, which includes the terminal's location information.

[0152] S503, the first network element sends the address information of the at least one first MEC application instance to the terminal. Correspondingly, the terminal receives the address information of the at least one first MEC application instance from the first network element.

[0153] For example, if the terminal requests a MEC application instance of MEC application 1, the first MEC application instance can be a MEC application instance of MEC application 1.

[0154] In this context, the address information of at least one first MEC application instance can be carried in the MEC application instance discovery response message.

[0155] The address information of an MEC application instance can be its IP address, URL, identifier, port number, or other address connection information that can uniquely connect to the MEC application instance.

[0156] If at least one first MEC application instance is a first MEC application instance, then the first MEC application instance can be the optimal MEC application instance determined by the first network element. In this case, the terminal can use the first MEC application instance as the MEC application instance providing services.

[0157] If at least one first MEC application instance is multiple first MEC application instances, then these multiple first MEC application instances can be the optimal multiple MEC application instances determined by the first network element. In this case, the terminal can select the optimal MEC application instance from them as the MEC application instance to provide services. This application does not limit the method by which the terminal determines which MEC application instance is the optimal MEC application instance.

[0158] Optionally, when at least one first MEC application instance is multiple first MEC application instances, the method further includes: the first network element sending priority information of the at least one first MEC application instance to the terminal. In this case, the terminal can select the MEC application instance with the highest priority as the MEC application instance providing the service. Of course, the terminal can also select other MEC application instances as the MEC application instances providing the service.

[0159] In this embodiment of the application, when a terminal requests an MEC application instance, the first network element determines the MEC application instance that provides services to the terminal based on the obtained location information of the terminal, thereby reducing the message transmission delay between the MEC application instance and the terminal and improving the quality of service.

[0160] Specifically, the first network element is responsible for the lifecycle management of MEC applications, including the selection of MEC application instance deployment locations. The first network element stores information for each MEC application instance, including the MEC application instance identifier, MEC application instance address, MEC application instance deployment location, and the correspondence between these information. Based on the terminal's location information and the MEC application instance's location information, the first network element determines at least one first MEC application instance from the MEC application instances; that is, the first network element determines one or more MEC application instances closest to the location identified by the terminal's location information as the first MEC application instance. The number of first MEC application instances to be determined by the first network element can be predefined, preset, or specified by the protocol; this application does not impose any restrictions.

[0161] For example, if a terminal requests a MEC application instance of MEC application 1, the terminal can access five MEC application instances of MEC application 1, denoted as MEC application instance 1, MEC application instance 2, MEC application instance 3, MEC application instance 4, and MEC application instance 5. Their distances from the terminal, from closest to furthest, are: MEC application instance 3, MEC application instance 2, MEC application instance 1, MEC application instance 4, and MEC application instance 5. If at least one first MEC application instance is a single first MEC application instance, the first network element can determine that MEC application instance 3 is at least one first MEC application instance. If at least one first MEC application instance is three first MEC application instances, the first network element can determine that MEC application instance 3, MEC application instance 2, and MEC application instance 1 are at least one first MEC application instance.

[0162] based on Figure 2 The network architecture shown, and Figure 1 , Figure 3 , Figure 3A , Figure 3B as well as Figure 3C The MEC architecture shown is Figure 6 This is a schematic diagram of another communication method (also known as another method for determining MEC application instances) provided in the embodiments of this application. Figure 6 The illustrated embodiment uses a variation of an MEC application instance as an example; it can also be implemented in... Figure 5 Once the MEC application instance shown is determined, the method of this embodiment will be executed when the MEC application instance needs to be changed. Figure 6 The following are included:

[0163] S601. The first network element subscribes to user plane path change notification events from a core network control plane functional network element, such as NEF, PCF, or SMF. The first network element can subscribe to user plane path change notification events by sending a user plane path change subscription request message. After sending the message, the first network element receives a response message from the core network control plane functional network element.

[0164] exist Figure 1 In the MEC architecture shown, the first network element can be a functional network element of the MEC system management plane. Figure 3A , Figure 3B and Figure 3C In the MEC architecture shown, the first network element can be an EES or an EDN CS.

[0165] In this system, the terminal accesses the application network (e.g., EDN) through a UPF, and different UPFs access application networks at different locations. When the terminal moves to different locations, the core network will switch the user plane path, selecting the optimal UPF to reduce access latency between the terminal and the application network and improve user experience. The process of switching to a new UPF results in a change in the user plane path.

[0166] S602. The terminal sends an MEC application instance change subscription request message to the first network element. The MEC application instance change subscription request message includes at least one of the following: terminal identifier, MEC application name, MEC application provider name, and MEC application version. After sending, the terminal receives a response message from the first network element.

[0167] When the first network element is a specific network element, step S602 can be executed by the terminal application. When the first network element is an EES, step S602 can be executed by the EEC in the terminal. When the first network element is an EDN CS, step S602 can be executed by the EDN CC in the terminal.

[0168] S603. The core network control plane functional network element sends a first notification message to the first network element to notify it that the user plane path of the terminal has changed. This first notification message can be a user plane path change notification message. Specifically, when a terminal moves, the core network control plane functional network element selects the optimal UPF for the terminal at the new location. Upon switching to the new UPF, a user plane handover occurs. The core network control plane functional network element sends a user plane path change notification message to the first network element. This message includes the terminal identifier (such as the terminal's IP address or Universal Subscriber Identity), source user plane location information, and destination user plane location information. The user plane location information can be a DNAI (User ID), and the DNAI corresponds to a cell.

[0169] S604: The first network element determines the source MEC application instance information based on the terminal identifier and the source user plane location information, and determines the destination MEC application instance based on the terminal identifier and the destination user plane location. The determination of a new MEC application instance based on the destination user plane location can also be referenced. Figure 5 Step S502 of the illustrated embodiment. The first network element can obtain the location information of the destination UPF by receiving user plane path change notification information. If there are multiple destination MEC application instances, one MEC application instance is selected. The selection strategy can be random selection or selection of the instance with the lightest load. After determining the new MEC application instance, the first network element instructs the source MEC application instance and the destination MEC application instance to complete the terminal context migration. The determined MEC application instance is the first MEC application instance.

[0170] The first network element sends a response message to the core network control plane functional network element in response to the user plane path change notification, enabling the core network control plane network function to control the user plane to complete the path switching.

[0171] In this embodiment, the destination UPF location information can also be considered as the current location of the terminal, which is a form of the terminal's location information.

[0172] S605. The first network element sends a MEC application instance change notification to the terminal. The MEC application instance change notification includes destination MEC application instance information, such as at least one of the following: MEC application name, MEC application provider name, MEC application version, MEC application instance identifier, and MEC application instance address. After receiving the MEC application instance change notification, the terminal can send a response to the first network element.

[0173] The terminal will then switch to using the new MEC application instance, i.e. the target MEC application instance.

[0174] In this embodiment, when the terminal changes due to a UPF change, the current MEC application instance may no longer be optimal. The first network element determines the optimal MEC application instance after switching to the new UPF by using the terminal's location information (destination user plane location), thereby reducing the packet transmission latency between the MEC application instance and the terminal and improving the quality of service.

[0175] based on Figure 2 The network architecture shown, and Figure 3 , Figure 3A , Figure 3B as well as Figure 3C The MEC architecture shown is Figure 6A This is a schematic diagram of a communication method (also known as a method for determining an application instance) provided in an embodiment of this application. Figure 6A The illustrated embodiment uses the discovery process of MEC application instances as an example, including:

[0176] S601A: The terminal sends a first message to the first network element. Correspondingly, the first network element receives the first message from the terminal.

[0177] The first message requests the address information of the MEC application instance, which is used by the terminal to connect to that MEC application instance. The first message can also be a discovery request message for the MEC application instance.

[0178] exist Figure 3A , Figure 3B and Figure 3CIn the MEC architecture shown, the first network element can be either EES or EDN CS. When the first network element is EES, the specific entity executing step S601A can be the EEC in the terminal; when the first network element is EDN CS, the specific entity executing step S601A can be either the EDN CC or the EEC in the terminal.

[0179] In this MEC application instance, the discovery request message originates from the terminal and reaches the first network element through access network devices (e.g., gNB), user plane gateways (e.g., UPF), etc.

[0180] Figure 6A The information included in the MEC application instance discovery request message in the illustrated embodiment is the same as described above. Figure 5 The information contained in the MEC application instance discovery request message in the illustrated embodiment is similar and will not be repeated here.

[0181] S602A: The first network element obtains information about at least one first EDN from the SMF, and the at least one first EDN is determined based on the location information of the terminal.

[0182] S603A, the first network element determines at least one first MEC application instance in at least one first EDN.

[0183] S604A: The first network element sends the address information of at least one first MEC application instance to the terminal.

[0184] For example, if the terminal requests a MEC application instance of MEC application 1, the first MEC application instance can be a MEC application instance of MEC application 1.

[0185] In this context, the address information of at least one first MEC application instance can be carried in the MEC application instance discovery response message.

[0186] The address information of an MEC application instance can be its IP address, URL, or other address connection information that can uniquely connect to the MEC application instance.

[0187] Optionally, when there are multiple first MEC application instances, the method further includes: the first network element sending priority information of at least one first MEC application instance to the terminal. In this case, the terminal can select the MEC application instance with the highest priority as the MEC application instance providing the service. Of course, the terminal can also select other MEC application instances as the MEC application instances providing the service.

[0188] In this embodiment of the application, when a terminal requests an MEC application instance, the first network element requests information of at least one first EDN from the SMF, thereby determining at least one first MEC application instance, thereby reducing the message transmission delay between the MEC application instance and the terminal and improving the quality of service.

[0189] Optionally, step S602A may include the following in its specific implementation:

[0190] 11) The first network element sends a third message to the SMF, the third message being used to request the deployment of at least one EDN of the MEC application instance with the terminal request. Correspondingly, the SMF receives the third message from the first network element.

[0191] 12) The SMF sends information about at least one first EDN to the first network element based on the third message. The first EDN is the EDN that deploys the MEC application instance requested by the terminal. Correspondingly, the first network element receives a response message from the SMF for the third message.

[0192] Information from at least one of the first EDNs can be carried in the response message of the third message.

[0193] For example, the third message can be a user plane management event notification message subscribed to by the first network element from the SMF, and the response message of the third message can be a user plane management event notification sent by the SMF to the first network element. Specifically, the response message of the third message can be a notification message sent by the SMF to the first network element immediately after receiving the subscription message. This notification message contains information about the EDN corresponding to the terminal's current location, such as the terminal's current user plane location information (DNAI).

[0194] The third message requests at least one EDN for the MEC application instance requested by the terminal. This can be understood as a request for an EDN that meets specific filtering conditions, which describe the conditions that the requested MEC application instance must satisfy. These specific filtering conditions can be sent by the terminal to the first network element in the first message, or generated independently by the first network element. For example, the third request message may also carry a filter to indicate the EDN information that meets the filter. For instance, if the filter is a MEC application instance that has deployed MEC application X, then the request indicates a request for the EDN of the MEC application instance that has deployed MEC application X.

[0195] Optionally, the information from the first EDN is used to indicate the performance of the communication path between the terminal and the first EDN. Since the EES and MEC application instances are deployed in the EDN, the information from the first EDN can also be considered to further indicate: the performance of the communication path between the terminal and the EES in the first EDN, and / or the performance of the communication path between the terminal and the MEC application instances in the first EDN.

[0196] The performance of a communication path can include performance indicators such as the network topology distance of the communication path, the latency of the communication path, and the bandwidth of the communication path.

[0197] Wherein, at least one first EDN and the information of at least one EDN can be any of the following:

[0198] Type 1: At least one first EDN is the EDN of all MEC application instances deployed with terminal requests. The information of the first EDN (denoted as the first information of the first EDN) includes any one or more of the following: the number of UPFs between the terminal and the first EDN, the mobile network intra-communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the mobile network intra-communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0199] Specifically, the first information of the first EDN can also be considered to include any one or more of the following: the number of UPFs between the terminal and the EES in the first EDN, the intra-mobile network communication latency between the terminal and the EES in the first EDN, the end-to-end communication latency between the terminal and the EES in the first EDN, the intra-mobile network communication bandwidth between the terminal and the EES in the first EDN, and the priority information of the communication path between the terminal and the EES in the first EDN. Alternatively, the first information of the first EDN can also be considered to include any one or more of the following: the number of UPFs between the terminal and the MEC application instances in the first EDN, the intra-mobile network communication latency between the terminal and the MEC application instances in the first EDN, the end-to-end communication latency between the terminal and the MEC application instances in the first EDN, the intra-mobile network communication bandwidth between the terminal and the MEC application instances in the first EDN, and the priority information of the communication path between the terminal and the MEC application instances in the first EDN.

[0200] For ease of description, the EDN on which the MEC application instance requested by the terminal is deployed will be referred to as the target EDN. Optionally, the third message includes information indicating the MEC application corresponding to the MEC application instance requested by the terminal (e.g., the identifier of the MEC application). The SMF can determine the MEC application corresponding to the MEC application instance requested by the terminal based on this information, and thus determine the EDN on which the MEC application instance is deployed as the target EDN.

[0201] In the first type, SMF does not need to select from all target EDNs; it only needs to use all target EDNs as at least one first EDN.

[0202] In the first type, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0203] The second method: at least one first EDN is the entire target EDN, and the information of a first EDN (denoted as the second information of the first EDN) is the DNAI of that first EDN.

[0204] In the second approach, SMF does not need to select from all target EDNs; it only needs to use all target EDNs as at least one first EDN.

[0205] In the second case, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0206] The third type: at least one first EDN is the target EDN of all, and the information of a first EDN is the identifier of the first EDN and the priority information of the first EDN.

[0207] In the third type, SMF does not need to select from all target EDNs; it only needs to determine the priority of all target EDNs.

[0208] The fourth type: At least one first EDN is a partial target EDN. The information of a first EDN is the first information of the first EDN.

[0209] In the fourth type, SMF can select a subset of target EDNs from all target EDNs as at least one first EDN.

[0210] In the fourth type, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0211] Type 5: At least one EDN is a partial target EDN, and the information of a first EDN is the DNAI of that first EDN.

[0212] In the fifth type, SMF can select a subset of target EDNs from all target EDNs as at least one first EDN.

[0213] In the fifth type, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0214] The sixth type: at least one first EDN is a partial target EDN, and the information of a first EDN is the identifier of the first EDN and the priority information of the first EDN.

[0215] In the sixth type, SMF can select a subset of target EDNs from all target EDNs as at least one first EDN.

[0216] In methods 4 to 6, SMF selects a subset of target EDNs from all target EDNs as at least one first EDN. This can be achieved through any one of the following methods 1 to 3.

[0217] Method 1

[0218] SMF can determine, based on the terminal's location information and the target EDN's location information, one or more target EDNs that are closest to the terminal's location as at least one first EDN. The closer the target EDN is to the terminal, the better the communication performance with the terminal is considered to be.

[0219] The terminal's location information can be carried in a third message or determined by the SMF based on the terminal's identifier. The EDN's location information can be determined based on the EDN's DNAI. "Closest to the target EDN and the terminal" means that the target EDN and the terminal have the shortest network connection distance.

[0220] For example, based on Figure 3C In the example shown, if the terminal requests a MEC application instance of MEC application 1, then all target EDNs can be EDN1, EDN2, and EDN3. If at least one first EDN is two EDNs, and the distances between the three EDNs and the terminal from closest to furthest are EDN2, EDN1, and EDN3, then SMF can determine that EDN2 and EDN1 are at least one first EDN.

[0221] Method 2

[0222] SMF can determine, based on the first information of the target EDN, one or more target EDNs with the best communication performance with the terminal among all target EDNs as at least one first EDN.

[0223] The communication performance between an EDN and a terminal can be characterized by one or more parameters among the following: the number of UPFs between the terminal and the EDN; the intra-mobile network communication latency between the terminal and the EDN; the end-to-end communication latency between the terminal and the EDN; the intra-mobile network communication bandwidth between the terminal and the EDN; and the performance indicators of other communication paths.

[0224] Depending on the parameters characterizing the communication performance between the EDN and the terminal, the at least one first EDN determined by the SMF may also be different. For example, if the communication performance between the EDN and the terminal is characterized by the end-to-end communication latency between the terminal and the EDN, and if at least one first EDN consists of three first EDNs, then the SMF can select the three target EDNs with the smallest end-to-end communication latency with the terminal from all target EDNs as at least one first EDN.

[0225] Method 3

[0226] SMF can determine at least one first EDN based on the terminal's location information and the information of the alternative EDNs.

[0227] Specifically, the SMF can determine at least one first EDN based on the terminal's location information, the information of the candidate EDNs, and the first information of the candidate or all EDNs. The candidate EDNs may or may not be the target EDNs; this application does not impose any restrictions.

[0228] For example, if the candidate EDN is a candidate target EDN, the SMF can determine one or more target EDNs among the candidate target EDNs that have the best communication performance with the terminal as at least one first EDN. As another example, the SMF can determine one or more target EDNs among the candidate target EDNs that have the best communication performance with the terminal, and one or more target EDNs among the non-candidate target EDNs that have the best communication performance with the terminal as at least one first EDN.

[0229] Optionally, the information of the candidate EDN is carried in the third message. The candidate EDN is determined by the first network element based on the terminal's location information and the EDN information stored in the first network element. There can be one or more candidate EDNs. The first network element can determine one or more EDNs (or target EDNs) closest to the terminal as candidate EDNs (or target EDNs) based on the terminal's location information. In this case, the first network element can be an EDN CS. Optionally, the SMF can determine the MEC application corresponding to the MEC application instance requested by the terminal based on the information in the first message indicating the MEC application instance corresponding to the MEC application requested by the terminal (e.g., the MEC application identifier), and then determine the EDN of the MEC application instance deployed with that MEC application as the target EDN.

[0230] In options 1 through 6, the priority of at least one first EDN can optionally be determined based on the distance between the at least one first EDN and the terminal, or based on the communication performance between the at least one first EDN and the terminal. For example, SMF can assign a higher priority to the first EDN that is closer to the terminal, or assign a higher priority to the first EDN that has better communication performance with the terminal.

[0231] It should be noted that, when the response message of the third message includes the priority of at least one first EDN, in specific implementation of step 12), the first network element can determine the MEC application instance requested by the terminal in some or all of the target EDNs in at least one first EDN as at least one first MEC application instance. In the above-described methods 1, 2, 4, and 5, if the response message of the third message does not include the priority of at least one first EDN, in specific implementation of step 12), the first network element can determine the priority of at least one first EDN based on the information of at least one first EDN, and then determine the MEC application instance requested by the terminal in some or all of the first EDNs as at least one first MEC application instance.

[0232] The method by which the first network element determines the priority of at least one first EDN is the same as that of SMF, as detailed above, and will not be repeated here.

[0233] Of course, the first network element can also use other methods to determine at least one first MEC application instance. For example, after receiving information from at least one first EDN, the first network element can combine the load of at least one first EDN to determine one or more first EDNs with smaller loads, and determine the MEC application instance requested by the terminal in one or more first EDNs with smaller loads as at least one first MEC application instance.

[0234] In this embodiment, if the first network element is an EDN CS, after determining at least one first MEC application instance, the first network element can also determine the EES associated with the at least one first MEC application instance, and the EES associated with the at least one first MEC application instance is deployed in at least one first EDN. Optionally, in this case, the above method further includes: the first network element sending the address information of the EES associated with the at least one first MEC application instance to the terminal. After receiving this information, the terminal can first access the EES, and then access the first MEC application instance managed by the EES.

[0235] based on Figure 2 The network architecture shown, and Figure 3 , Figure 3A , Figure 3B as well as Figure 3C The MEC architecture shown is Figure 6B This is a schematic diagram of a communication method (also known as an EES determination method) provided in an embodiment of this application. Figure 6B The illustrated embodiment uses the discovery process of EES as an example, including:

[0236] S601B: The terminal sends a first message to the first network element. Correspondingly, the first network element receives the first message from the terminal.

[0237] The first message can be used to request the address information of the EES, which is used to connect to the EES. The first message can be an EES discovery request message.

[0238] The first network element can be EDN CS, and the specific execution step S601B can be EDN CC or EEC in the terminal.

[0239] The EES discovery request message originates from the terminal and travels through access network devices (e.g., gNB), user plane gateways (e.g., UPF), etc., to the first network element.

[0240] The information included in the EES discovery request message is the same as described above. Figure 5 The MEC application instance discovery request message in the illustrated embodiment is similar, except that the MEC application instance information in the MEC application instance discovery request message serves the purpose of instructing the MEC application instance to obtain the address information of the EES of the MEC application instance that manages it.

[0241] S602B: The first network element obtains information about at least one first EDN from the SMF, and the at least one first EDN is determined based on the terminal's location information.

[0242] S603B, the first network element determines at least one first EES in at least one first EDN.

[0243] S604B: The first network element sends address information of at least one first EES to the terminal. Correspondingly, the terminal receives address information of at least one first EES from the first network element.

[0244] For example, if a terminal requests an EES for managing the MEC application instance of MEC application 1, the first EES can be the EES for managing the MEC application instance of MEC application 1.

[0245] In this context, the address information of at least one first EES can be carried in the response message of the first message, and the response message of the first message can be in the EES discovery response message.

[0246] The address information of an EES can be its IP address, URL, or other address connection information that can uniquely connect to the EES.

[0247] Optionally, if at least one first EES is multiple first EESs, the method further includes: the first network element sending priority information of at least one first EES to the terminal. In this case, the terminal can select the EES with the highest priority as the EES providing the service. Of course, the terminal can also select other EES as the EES providing the service.

[0248] In this embodiment of the application, when a terminal requests an EES, the first network element requests information of at least one first EDN from the SMF, thereby determining at least one first EES, thereby reducing the message transmission delay between the MEC application instance managed by the EES and the terminal, and improving the quality of service.

[0249] Optionally, step S602B may include the following in a specific implementation:

[0250] 21) The first network element sends a third message to the SMF, the third message being used to request the deployment of at least one EDN of the EES with the terminal request. Correspondingly, the SMF receives the third message from the first network element.

[0251] 22) The SMF sends information about at least one first EDN to the first network element based on the third message. The first EDN is the EDN of the EES that has been deployed with the terminal request. Correspondingly, the first network element receives a response message from the SMF for the third message.

[0252] Information from at least one of the first EDNs can be carried in the response message of the third message.

[0253] For example, the third message can be a user plane management event notification message subscribed to by the first network element from the SMF, and the response message of the third message can be a user plane management event notification sent by the SMF to the first network element. Specifically, the response message of the third message can be a notification message sent by the SMF to the first network element immediately after receiving the subscription message. This notification message contains information about the EDN corresponding to the terminal's current location, such as the terminal's current user plane location information (DNAI).

[0254] The third message requests at least one EDN from which the EES requested by the terminal is deployed. This can be understood as a request for an EDN that meets specific filtering conditions, which describe the conditions that the EES requested by the terminal must satisfy. These specific filtering conditions can be sent by the terminal to the first network element in the first message, or generated independently by the first network element. For example, the third request message may also carry a filter to indicate the EDN information requested that meets the filter. For instance, if the filter is an EES that manages the MEC application instance of MEC application X, then it indicates a request for an EDN from which the EES that manages the MEC application instance of MEC application X is deployed.

[0255] Optionally, the information from the first EDN is used to indicate the communication performance of the communication path between the terminal and the first EDN. Since the EES and MEC application instances are deployed in the EDN, the information from the first EDN can also be considered to indicate: the communication performance of the communication path between the terminal and the EES in the first EDN, and / or the communication performance of the communication path between the terminal and the MEC application instances in the first EDN.

[0256] The performance of a communication path can include performance indicators such as the network topology distance of the communication path, the latency of the communication path, and the bandwidth of the communication path.

[0257] Wherein, at least one first EDN and the information of at least one EDN can be any of the following:

[0258] Type 1: At least one first EDN is the EDN of all EES deployed with terminal requests. The information of the first EDN (denoted as the first information of the first EDN) includes any one or more of the following: the number of UPFs between the terminal and the first EDN, the mobile network intra-communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the mobile network intra-communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0259] Specifically, the first information of the first EDN can also be considered to include any one or more of the following: the number of UPFs between the terminal and the EES in the first EDN, the intra-mobile network communication latency between the terminal and the EES in the first EDN, the end-to-end communication latency between the terminal and the EES in the first EDN, the intra-mobile network communication bandwidth between the terminal and the EES in the first EDN, and the priority information of the communication path between the terminal and the EES in the first EDN. Alternatively, the first information of the first EDN can also be considered to include any one or more of the following: the number of UPFs between the terminal and the MEC application instances in the first EDN, the intra-mobile network communication latency between the terminal and the MEC application instances in the first EDN, the end-to-end communication latency between the terminal and the MEC application instances in the first EDN, the intra-mobile network communication bandwidth between the terminal and the MEC application instances in the first EDN, and the priority information of the communication path between the terminal and the MEC application instances in the first EDN.

[0260] For ease of description, the EDN that deploys the EES requested by the terminal will be referred to as the target EDN in the following text. Optionally, the third message includes information indicating the EES requested by the terminal. The SMF can determine the EES requested by the terminal based on this information, and thus determine the EDN that deploys the EES as the target EDN.

[0261] In the first type, SMF does not need to select from all target EDNs; it only needs to use all target EDNs as at least one first EDN.

[0262] In the first type, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0263] The second method: at least one first EDN is the entire target EDN, and the information of a first EDN (denoted as the second information of the first EDN) is the DNAI of that first EDN.

[0264] In the second approach, SMF does not need to select from all target EDNs; it only needs to use all target EDNs as at least one first EDN.

[0265] In the second case, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0266] The third type: at least one first EDN is the target EDN of all, and the information of a first EDN is the identifier of the first EDN and the priority information of the first EDN.

[0267] In the third type, SMF does not need to select from all target EDNs; it only needs to determine the priority of all target EDNs.

[0268] The fourth type: At least one first EDN is a partial target EDN. The information of a first EDN is the first information of the first EDN.

[0269] In the fourth type, SMF can select a subset of target EDNs from all target EDNs as at least one first EDN.

[0270] In the fourth type, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0271] Type 5: At least one EDN is a partial target EDN, and the information of a first EDN is the DNAI of that first EDN.

[0272] In the fifth type, SMF can select a subset of target EDNs from all target EDNs as at least one first EDN.

[0273] In the fifth type, optionally, the response message of the third message sent by the SMF to the first network element includes priority information of at least one first EDN.

[0274] The sixth type: at least one first EDN is a partial target EDN, and the information of a first EDN is the identifier of the first EDN and the priority information of the first EDN.

[0275] In the sixth type, SMF can select a subset of target EDNs from all target EDNs as at least one first EDN.

[0276] In methods 4 to 6, SMF selects a subset of target EDNs from all target EDNs as at least one first EDN. This can be achieved through any one of the following methods 1 to 3.

[0277] Method 1

[0278] SMF can determine, based on the terminal's location information and the target EDN's location information, one or more target EDNs that are closest to the terminal's location as at least one first EDN. The closer the target EDN is to the terminal, the better the communication performance with the terminal is considered to be.

[0279] The terminal's location information can be carried in a third message or determined by the SMF based on the terminal's identifier. The EDN's location information can be determined based on the EDN's DNAI. "Closest to the target EDN and the terminal" means that the target EDN and the terminal have the shortest network connection distance.

[0280] For example, based on Figure 3C In the example shown, if the terminal requests the EES to manage the MEC application instance of MEC application 1, then all target EDNs can be EDN1, EDN2, and EDN3. If at least one first EDN is two EDNs, and the distances between the three EDNs and the terminal from closest to furthest are EDN2, EDN1, and EDN3, then the SMF can determine that EDN2 and EDN1 are at least one first EDN.

[0281] Method 2

[0282] SMF can determine, based on the first information of the target EDN, one or more target EDNs with the best communication performance with the terminal among all target EDNs as at least one first EDN.

[0283] The communication performance between an EDN and a terminal can be characterized by one or more parameters among the following: the number of UPFs between the terminal and the EDN; the intra-mobile network communication latency between the terminal and the EDN; the end-to-end communication latency between the terminal and the EDN; the intra-mobile network communication bandwidth between the terminal and the EDN; and the performance indicators of other communication paths.

[0284] Depending on the parameters characterizing the communication performance between the EDN and the terminal, the at least one first EDN determined by the SMF may also be different. For example, if the communication performance between the EDN and the terminal is characterized by the end-to-end communication latency between the terminal and the EDN, and if at least one first EDN consists of three first EDNs, then the SMF can select the three target EDNs with the smallest end-to-end communication latency with the terminal from all target EDNs as at least one first EDN.

[0285] Method 3

[0286] SMF can determine at least one first EDN based on the terminal's location information and the information of the alternative EDNs.

[0287] Specifically, the SMF can determine at least one first EDN based on the terminal's location information, the information of the candidate EDNs, and the first information of the candidate or all EDNs. The candidate EDNs may or may not be the target EDNs; this application does not impose any restrictions.

[0288] For example, if the candidate EDN is a candidate target EDN, the SMF can determine one or more target EDNs among the candidate target EDNs that have the best communication performance with the terminal as at least one first EDN. As another example, the SMF can determine one or more target EDNs among the candidate target EDNs that have the best communication performance with the terminal, and one or more target EDNs among the non-candidate target EDNs that have the best communication performance with the terminal as at least one first EDN.

[0289] Optionally, the information of the candidate EDN is carried in the third message. The candidate EDN is determined by the first network element based on the terminal's location information and the EDN information stored in the first network element. There can be one or more candidate EDNs. The first network element can determine one or more EDNs (or target EDNs) closest to the terminal as candidate EDNs (or target EDNs) based on the terminal's location information. In this case, the first network element can be an EDN CS. Optionally, the SMF can determine the MEC application corresponding to the MEC application instance requested by the terminal based on the information in the first message indicating the MEC application instance corresponding to the MEC application requested by the terminal (e.g., the MEC application identifier), and then determine the EDN of the EES that deploys the MEC application instance managing the MEC application as the target EDN.

[0290] In options 1 through 6, the priority of at least one first EDN can optionally be determined based on the distance between the at least one first EDN and the terminal, or based on the communication performance between the at least one first EDN and the terminal. For example, SMF can assign a higher priority to the first EDN that is closer to the terminal, or assign a higher priority to the first EDN that has better communication performance with the terminal.

[0291] It should be noted that, when the response message of the third message includes the priority of at least one first EDN, in specific implementation of step 22), the first network element can determine the EES requested by the terminal in some or all of the target EDNs in at least one first EDN as at least one first EES. In the above-described methods 1, 2, 4, and 5, if the response message of the third message does not include the priority of at least one first EDN, in specific implementation of step 22), the first network element can determine the priority of at least one first EDN based on the information of at least one first EDN, and then determine the EES requested by the terminal in some or all of the first EDNs as at least one first EES.

[0292] The method by which the first network element determines the priority of at least one first EDN is the same as that of SMF, as detailed above, and will not be repeated here.

[0293] Of course, the first network element can also use other methods to determine at least one first EES. For example, after receiving information from at least one first EDN, the first network element can combine the load of at least one first EDN to determine one or more first EDNs with smaller loads, and determine the EES requested by the terminals in one or more first EDNs with smaller loads as at least one first EES.

[0294] exist Figure 6A as well as Figure 6B In the embodiments shown, the actions performed by the SMF can also be performed by the network management system, and this application does not impose any restrictions.

[0295] It should be noted that, as Figure 6G As shown, a PLMN#A can set local egress points DNAI#A1, DNAI#A2, and DNAI#A3 at its network edge, and a PLMN#B can set local egress points DNAI#B1, DNAI#B2, and DNAI#B3 at its network edge. DNAI#A1 and DNAI#A2 correspond to EDN#1, and DNAI#A3 corresponds to EDN#2. This can also be understood as the (optimal) service area corresponding to EDN#1 being the area identified by DNAI#A1 and DNAI#A2, and the (optimal) service area corresponding to EDN#2 being the area identified by DNAI#A3. Similarly, DNAI#B1 corresponds to EDN#3, and DNAI#B2 and DNAI#B3 correspond to EDN#4. This can also be understood as the (optimal) service area corresponding to EDN#3 being the area identified by DNAI#B1, and the (optimal) service area corresponding to EDN#4 being the area identified by DNAI#B2 and DNAI#B3.

[0296] It should be noted that an EDN can correspond to one or more DNAIs, and these one or more DNAIs can all be used by the terminal to access the EDN (specifically, they can be EES or EAS in the EDN, etc.). In the above embodiments, the DNAI of a first EDN may include at least one DNAI corresponding to the first EDN.

[0297] The above Figure 6B In the scheme shown, the first network element can be either an EDN CS or an EES that manages other EESs.

[0298] See Figure 6C (a) or Figure 6C In (b) of this example, the EDN CS and EES can reside in the same DN. In this case, the EDN CS and EES can be associated with the same SMF (see [reference]). Figure 6C (a) in the text can also be associated with different SMFs (see [link]). Figure 6C (b)). EDN CS and EES can also be located in different DNs (see (b)). Figure 6C In (c) of this case, EDN CS and EES are associated with different SMFs.

[0299] A terminal can establish a PDU session to access the DN to which the EES belongs, and it can also establish a PDU session to access the DN to which the EDN CS belongs. When the EES and EDN CS are located in the same DN, the terminal can establish one PDU session to access both the EES and the EDN CS; alternatively, the terminal can establish two separate PDU sessions, one for accessing the EDN CS and the other for accessing the EES. The SMF associated with the EDN CS is used by the terminal to access the EDN CS session. The SMF associated with the EDN CS is generally a centralized (or remote) SMF, or it can be understood as the SMF located close to the EDN CS, or it can be understood as the SMF associated with the EDN CS being unrelated to the terminal's current location. The SMF associated with the EES is used by the terminal to access the EES session. The SMF associated with the EES is generally the SMF closest to the EES, or it can be understood as being close to the terminal's current location. Figure 6C (b) or Figure 6C In (c), SMF1 is the SMF associated with EDN CS, and SMF2 is the SMF associated with EES. Generally, EES or EDN CS can communicate with its associated SMF.

[0300] based on Figure 6C (a) Figure 6C (b) or Figure 6C In section (c), this application provides the following communication method (also referred to as an EES determination method), such as... Figure 6D As shown, it includes: S601D, whereby a first network element obtains information about at least one first EDN from a second network element. The at least one first EDN is determined based on at least one of the terminal's location information or the terminal's service information.

[0301] The second network element is either the first SMF or NEF. The first network element can be an EDN CS or an EES that manages other EESs. The first SMF can be an SMF associated with the first network element, or it can be any other SMF that can communicate with the first network element.

[0302] Optionally, in one scenario, before step S601D, the method further includes step S601B as described above. For a description of step S601B, please refer to the above text; it will not be repeated here. In another scenario, optionally, before step S601D, the source EES sends a request for the target EES to the first network element. Of course, step S601D can also be triggered under other circumstances or events.

[0303] S602D: The first network element determines at least one first EES based on information from at least one first EDN. A description of step S602D is provided in S602B above and will not be repeated here.

[0304] S603D: The first network element sends the address information of at least one first EES to the terminal. The relevant description of step S603D is given in S603B above and will not be repeated here.

[0305] For details regarding the first EES and its address information, please refer to the above text, which will not be repeated here.

[0306] Optionally, if at least one first EES is multiple first EES, the method further includes: the first network element sending priority information of at least one first EES to the terminal. A description of this optional method can be found above. Figure 6B The relevant descriptions in the illustrated scheme will not be repeated here.

[0307] In this embodiment of the application, when a terminal requests an EES, the first network element requests information of at least one first EDN from the second network element, thereby determining at least one first EES, thereby reducing the message transmission delay between the MEC application instance managed by the EES and the terminal, and improving the quality of service.

[0308] Optionally, the above step S601D may include the following in its specific implementation:

[0309] 31) The first network element sends a third message to the second network element. The third message includes at least one of the following: information for determining the location of the terminal or service information of the terminal. The third message is used to request information from at least one EDN, which has deployed an EES matching the terminal request. Specifically, the third message can also be understood as requesting the DNAI of at least one EDN matching the information in the third message. The second network element receives the third message from the first network element.

[0310] 32) The second network element sends at least one piece of information about a first EDN to the first network element according to the third message. Correspondingly, the first network element receives at least one piece of information about a first EDN from the second network element. The information about at least one first EDN may be carried in the response message of the third message.

[0311] The information used to determine the terminal's location can be the terminal's location information itself, such as network location (e.g., cell ID of the cell the terminal is in), TA information (e.g., tracking area identity (TAI) of the tracking area (TA) the terminal is in, or other geographical or administrative location information. Alternatively, the information used to determine the terminal's location can be the terminal's identifier (UE ID), EEC identifier, or application user identifier, etc., based on which the terminal's location information can be determined. The terminal's location information can indicate the terminal's current location.

[0312] Service information may include network information and / or application information. Network information may be a data network name (DNN), or DNN and slice information. Slice information may be, for example, single network slice selection assistance information (S-NSSAI). Application information includes application identifiers or application client identifiers. Application identifiers may be application identifiers, application triples, etc. The DNN and slice information may differ from the DNN and slice information of the EDN CS corresponding to the current terminal's connection to the EDN CS session; that is, this information may be the DNN and slice information corresponding to EES, such as the DNN of an Edge-dedicated DN. The terminal's service information may include service information corresponding to applications installed on the terminal, service information corresponding to applications currently running on the terminal, service information of applications the terminal is about to access, or service information of applications the terminal is interested in. Applications may be mobile apps or web applications, etc.

[0313] For example, the third message can be a UE network location request or a DNAI request. The response message to the third message can be a UE network location response or a DNAI response. Both the third message and its response can be service-based APIs. Further descriptions of the third message can be found above. Figure 6B The relevant descriptions in the illustrated scheme will not be repeated here.

[0314] If the third message includes the terminal's location information, the second network element directly determines the terminal's location information based on the third message. If the third message includes the terminal's identifier, the EEC's identifier, or the application user's identifier, the second network element determines the terminal's location information based on these identifiers.

[0315] Optionally, the information of the first EDN includes at least one DNAI corresponding to the first EDN. Optionally, the information of the first EDN also includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN. Further descriptions of the information of the first EDN can be found above. Figure 6B The relevant descriptions in the illustrated scheme will not be repeated here.

[0316] For a description of determining at least one first EES, please refer to the above. Figure 6B The relevant descriptions in the illustrated scheme will not be repeated here.

[0317] In the first scenario, the SMF may include a mapping relationship between at least two of the following: location area (e.g., cell, TA) information, EDN information (e.g., DNAI) information, and service information. For example, the SMF may contain a mapping relationship between cell (or TA) and DNAI, and a mapping relationship between DNAI and service. In this case, the second network element can determine the SMF that matches the service area of ​​the terminal with the location area (e.g., cell, TA) where the terminal is located based on the terminal's location information, and request information from the SMF to obtain at least one first EDN.

[0318] In the first case, optionally, step 32) above may include the following in its implementation:

[0319] 41) The second network element determines the second SMF based on the terminal's location information. For example, the second network element can determine the location area (e.g., cell, TA) of the terminal based on the terminal's location information, and then determine the SMF that matches the service area with the location area of ​​the terminal as the second SMF. Alternatively, the second network element can request the SMF that matches the service area with the location area of ​​the terminal from the NRF. The NRF determines the SMF that matches the service area with the location area of ​​the terminal and returns the information of the SMF that matches the service area with the location area of ​​the terminal to the second network element. The second network element obtains the information of the SMF that matches the service area with the location area of ​​the terminal from the NRF and determines the second SMF based on this information.

[0320] 42) The second network element sends a request message to the second SMF. The request message includes at least one of location information or service information, wherein the location information includes the location information of the terminal, and the service information includes the service information of the terminal. Correspondingly, the second SMF receives the request message from the second network element. The request message is used to obtain EDN information that matches at least one of the location information or service information.

[0321] 43) When the request message includes location information, the second SMF determines at least one piece of information about the first EDN based on the location information and the first correspondence, wherein the first correspondence includes the correspondence between location area information and EDN information; or,

[0322] When the request message includes business information, the second SMF determines at least one piece of information about the first EDN based on the business information and the second correspondence, wherein the second correspondence includes the correspondence between the business information and the EDN information; or...

[0323] When the request message includes location information and service information, the second SMF determines at least one piece of information of the first EDN based on the location information, service information, and a third correspondence. The third correspondence includes the correspondence between location area information, EDN information, and service information.

[0324] 44) The second SMF sends at least one piece of information about the first EDN to the second network element. Correspondingly, the second network element receives at least one piece of information about the first EDN from the second SMF.

[0325] 45) The second network element sends at least one piece of information about the first EDN to the first network element.

[0326] The location area information in the correspondence (first correspondence or third correspondence) stored in the second SMF can be the location area information served by the second SMF.

[0327] Step 43) In a specific implementation, when the request message includes location information, the second SMF uses the information of the EDN corresponding to the location information as information of at least one first EDN. For example, assuming the first correspondence is as shown in Table 1, if the location information is cell 1, the second SMF can determine that DNAI1 is information of at least one first EDN. If the location information is cell 2, the second SMF can determine that DNAI2 and DNAI3 are information of at least one first EDN.

[0328] Table 1

[0329]

[0330]

[0331] Step 43) In a specific implementation, when the request message includes business information, the second SMF uses the information of the EDN corresponding to the business information as information of at least one first EDN. For example, assuming the second correspondence is as shown in Table 2, if the business information is DNN1, then the second SMF can determine that DNAI1 is information of at least one first EDN. If the business information is DNN2, then the second SMF can determine that DNAI2 and DNAI3 are information of at least one first EDN.

[0332] Table 2

[0333]

[0334] Step 43) In specific implementation, when the request message includes location information and service information, the second SMF will use the information of the EDN corresponding to both the location information and the service information as information of at least one first EDN. For example, assuming the third correspondence is as shown in Table 3, if the location area is cell 2 and the service information is DNN1, then the second SMF can determine that DNAI2 is information of at least one first EDN.

[0335] Table 3

[0336]

[0337] In the second case, the NEF may include a correspondence between at least two of the following: location area (e.g., cell, TA) information, EDN information (e.g., DNAI) and service information. In this case, the second network element can be the NEF, and the second network element can determine at least one first EDN information based on at least one of the terminal's location information or service information.

[0338] In the second case, optionally, step 32) above may include the following in its implementation:

[0339] 51) The second network element determines at least one piece of information about the first EDN based on the terminal's location information and the first correspondence relationship, wherein the first correspondence relationship includes the correspondence between location area information and EDN information; or,

[0340] The second network element determines at least one piece of information about the first EDN based on the terminal's service information and the second correspondence, wherein the second correspondence includes the correspondence between the service information and the EDN information; or...

[0341] The second network element determines at least one piece of information about the first EDN based on the terminal's location information, service information, and a third correspondence. The third correspondence includes the correspondence between location area information, EDN information, and service information.

[0342] 52) The second network element sends at least one piece of information about the first EDN to the first network element.

[0343] The NEF can store at least one of the aforementioned first, second, and third correspondences. The location area information in the correspondences stored in the NEF can be information on all location areas. The specific implementation process of step 51) is similar to that of step 43) above, except that it is executed by the second network element here.

[0344] In the specific implementation of step 32) above, if at least one first EDN is determined based on the terminal's location information and the first correspondence, the determined first EDN information can be optimal (physically closest to the terminal, with the shortest network connection path, or with the optimal network connection path), and fast data transmission for the terminal can be guaranteed. If at least one first EDN is determined based on the terminal's service information and the second correspondence, the determined first EDN information can meet the terminal's service requirements. If at least one first EDN is determined based on the terminal's location information, service information, and the third correspondence, the determined first EDN information can be optimal and meet the terminal's service requirements, and fast data transmission for the terminal can be guaranteed.

[0345] See Figure 6C ,exist Figure 6C In (a), the EES and EDN CS reside in the same DN. If the EDN CS provides service information to the SMF, the SMF can determine which DNAI should be fed back to the EDN CS based on the service information. Figure 6C In (b) of the above, when the EES and EDN CS are located in the same DN but use different sessions, and these different sessions are managed by different SMFs, when the EDN CS requests the corresponding DNAI for the terminal from SMF1, DNAI2 should be the optimal DNAI, but SMF1 may not be able to provide DNAI2. Figure 6C In step (c), the EES and EDN CS reside in different DNs and use different sessions, which are managed by different SMFs. When the EDN CS requests a DNAI from SMF1 for a terminal, DNAI2 should be the optimal DNAI, but SMF1 may not be able to provide DNAI2. In the specific implementation of step 32), the NEF or the first SMF sends a request message to the second SMF, enabling the second SMF to send the optimal DNAI to the NEF or the first SMF, thus allowing the first network element to obtain the optimal DNAI. Alternatively, the NEF can determine the optimal DNAI by storing the above correspondence, thereby enabling the first network element to obtain the optimal DNAI.

[0346] Furthermore, if a terminal requests an EES but there is no specific service yet, there is no corresponding EES or EAS managed by the EES. In this case, the corresponding DNAI cannot be obtained through the existing mechanism of subscribing to user plane path management events (UP pathmanagementevent NOTI). This application provides a session-independent method for determining the DNAI for a terminal. The platform corresponding to this DNAI supports the service the terminal wants to access, and the optimal DNAI corresponding to the service accessed by the terminal can be obtained.

[0347] In order to make the above Figure 6D The method shown is clearer, and the following will explain it more clearly. Figure 6E and Figure 6F For the first and second scenarios mentioned above, Figure 6D The process of the first network element in the method shown to obtain information of at least one first EDN is illustrated by way of example.

[0348] In the first case, see Figure 6E , Figure 6E The process of the method shown includes:

[0349] S601E: The first network element sends a third message to the second network element, the third message including at least one of information for determining the location of the terminal or service information of the terminal. Correspondingly, the second network element receives the third message from the first network element.

[0350] After receiving the third message, the second network element can determine the location information of the terminal based on the information in the third message used to determine the location of the terminal. For details, please refer to the description above, which will not be repeated here.

[0351] The third message can be a UE network location request or a DNAI request.

[0352] S602E, the second network element determines the second SMF based on the terminal's location information.

[0353] In the specific implementation of step S602E, if the second network element includes the topology information of the SMF, the second network element determines the SMF that matches the service area and the location area of ​​the terminal based on the terminal's location information as the second SMF.

[0354] If the second network element does not include the topology information of the SMF, the second network element and the NRF interact to determine the second SMF. Specifically, the second network element sends an SMF request message (e.g., an NF request) to the NRF. The SMF request message requests information about an SMF whose service area matches the location area of ​​the terminal. The SMF request message includes the terminal's location information and, optionally, the NF type, which is the SMF type. The NRF uses the information in the SMF request message and network information (DNN and slice information) to find the second SMF information for the NEF and returns the second SMF information to the NEF. The second SMF information can be carried in the SMF request response (e.g., an NF response).

[0355] S603E: The second network element sends a request message to the second SMF, the request message including at least one of location information or service information. Correspondingly, the second SMF receives the request message from the second network element.

[0356] For example, the request message can be a UE network location request or a DNAI request.

[0357] S604E, the second SMF determines at least one piece of information about the first EDN based on the information and correspondence (first correspondence, second correspondence, or third correspondence) in the request message.

[0358] The relevant description of step S604E can be found above and will not be repeated here.

[0359] S605E and the second SMF send at least one piece of information from the first EDN to the second network element.

[0360] For example, information from at least one first EDN may be carried in the UE networklocation response or DNAI response sent by the second SMF to the second network element.

[0361] S606E: The second network element sends at least one piece of information about the first EDN to the first network element.

[0362] For example, information from at least one first EDN may be carried in a UE network location response or DNAI response sent by the second network element to the first network element.

[0363] In the second case, see Figure 6F The second network element is NEF. Figure 6F The process of the method shown includes:

[0364] S601F is the same as step S601E.

[0365] S602F and the second network element determine at least one EDN information based on at least one of the terminal's location information or service information, and the corresponding relationship (first corresponding relationship, second corresponding relationship, or third corresponding relationship).

[0366] The implementation process of step S602F can be found in the above process and will not be repeated here.

[0367] S603F: The second network element sends at least one piece of information about the first EDN to the first network element.

[0368] For example, information from at least one first EDN can be carried in the UE networklocation response or DNAI response sent by the second network element to the first network element. (The above...) Figure 6D , Figure 6E and Figure 6F The actions performed by NEF in the illustrated scheme can also be performed by NRF, UDR, etc., and this application does not impose any restrictions.

[0369] In the above embodiments, EDN CS can also be referred to as edge configuration server (ECS).

[0370] The above mainly describes the solution provided in this application from the perspective of interaction between various network elements. It is understood that, in order to achieve the above functions, each network element includes corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0371] It is understood that in the above method embodiments, the steps or operations corresponding to those implemented by the terminal, the first network element, and the SMF can also be implemented by components (such as chips or circuits) configured in the terminal, the first network element, and the SMF.

[0372] This application also provides an apparatus for implementing any of the above methods. For example, an apparatus is provided that includes a unit (or means) for implementing the various steps performed by the first network element in any of the above methods.

[0373] refer to Figure 7 This is a schematic diagram of a communication device provided in an embodiment of this application. The device is used to implement the various steps performed by the corresponding first network element in the above method embodiments, such as... Figure 7 As shown, the device 700 includes a transmitting unit 710, a receiving unit 720, and a processing unit 730.

[0374] The receiving unit 720 is used to receive the first message sent by the terminal to the first network element. The first message may be an MEC application instance discovery request message.

[0375] The processing unit 730 is used to determine at least one first MEC application instance, specifically by obtaining the location information of the terminal and then determining at least one first MEC application instance based on the location information.

[0376] In one possible implementation, if the MEC application instance discovery request message received by the first network element contains the terminal's location information, it is considered that the first network element obtains the terminal's location information by receiving the MEC application instance discovery request message. If the MEC application instance discovery request message does not contain the terminal's location information, another optional method is that the first network element obtains the terminal's location information from the telecom operator's network functions, such as the 5G core network control plane network functions (e.g., NEF), based on the terminal identifier. NEF provides an API, opening up the capabilities of the telecom network. The first network element sends a location query request including the terminal identifier to NEF. After receiving the location query request, NEF calls the core network functions, such as AMF, to obtain the location information. AMF sends the queried terminal's location information to the caller, i.e., NEF. NEF then sends a second message to the first network element, which includes the terminal's location information.

[0377] The sending unit 710 is configured to send an MEC application instance discovery response message to the terminal. The MEC application instance discovery response message includes information about at least one identified first MEC application instance.

[0378] It is understandable that the above-mentioned units can also be called modules or circuits, and the above-mentioned units can be set up independently or integrated in whole or in part.

[0379] In some possible implementations, the aforementioned transmitting unit 710 and receiving unit 720 can also be implemented as a transceiver unit, or in other words, the transmitting unit 710 and receiving unit 720 can be collectively referred to as a transceiver unit, and can be implemented through a communication interface. The aforementioned processing unit 730 can be implemented through a processor.

[0380] Optionally, the communication device 700 may further include a storage unit for storing data or instructions (also referred to as code or programs). The various units described above can interact with or be coupled to the storage unit to implement corresponding methods or functions. For example, the processing unit can read data or instructions from the storage unit, enabling the communication device to implement the methods described in the above embodiments.

[0381] refer to Figure 8 This is a schematic diagram of a communication device provided in an embodiment of this application. This device is used to implement the various steps executed by the corresponding control plane functional network element or terminal device in the above method embodiments, such as... Figure 8 As shown, the device 800 includes a transmitting unit 810 and a receiving unit 820, and optionally a processing unit 830. The transmitting unit 810 can be used to perform transmitting-related steps, such as sending information, messages, or requests, to the corresponding control plane function network element or terminal device in the above method embodiments. The receiving unit 820 can be used to perform receiving-related steps, such as receiving information, messages, or responses, to the corresponding control plane function network element or terminal device in the above method embodiments. Optionally, the processing unit 830 is used to process information or related information or messages.

[0382] This application also provides a communication system, which may include the first network element and the control plane function network element described in the above method embodiments. It may further include edge nodes equipped with MEC application instances, or may further include terminal devices.

[0383] When using integrated units, Figure 8A A possible structural schematic diagram of the communication device (referred to as communication device 80A) involved in the above embodiments is shown. The communication device 80A includes a processing unit 801A and a communication unit 802A, and may also include a storage unit 803A. Figure 8A The structural diagram shown can be used to illustrate the structure of the first network element or SMF involved in the above embodiments.

[0384] when Figure 8A The structural diagram shown is used to illustrate the structure of the first network element involved in the above embodiments. In one implementation:

[0385] Communication unit 802A is used to obtain information of at least one first EDN from SMF, wherein the at least one first EDN is determined according to the location information of the terminal;

[0386] Processing unit 801A is configured to determine at least one first MEC application instance in the at least one first EDN;

[0387] The communication unit 802A is also used to send the address information of the at least one first MEC application instance to the terminal.

[0388] Optionally, the communication unit 802A is specifically configured to: send a third message to the SMF, the third message being used to request at least one EDN, the at least one EDN deploying the MEC application instance requested by the terminal; and receive a response message from the SMF for the third message, the response message including information about the at least one first EDN.

[0389] Optionally, the third message includes information about alternative EDNs, which are determined by the first network element based on the location information of the terminal and the EDN information stored in the first network element.

[0390] Optionally, the third message may include the location information of the terminal.

[0391] Optionally, the information of the first EDN includes: the DNAI of the first EDN.

[0392] Optionally, the communication unit 802A is also configured to send the address information of the EES associated with the at least one first MEC application instance to the terminal.

[0393] Optionally, the information from the first EDN is used to indicate the communication performance of the communication path between the terminal and the first EDN.

[0394] Optionally, the information of the first EDN may also include at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0395] Optionally, the communication unit 802A is also used to send priority information of the at least one first MEC application instance to the terminal.

[0396] In another implementation:

[0397] Communication unit 802A is used to obtain information of at least one first EDN from SMF, wherein the at least one first EDN is determined according to the location information of the terminal;

[0398] Processing unit 801A is configured to determine at least one first EES in the at least one first EDN;

[0399] The communication unit 802A is also used to send the address information of the at least one first EES to the terminal.

[0400] Optionally, the communication unit 802A is specifically configured to: send a third message to the SMF, the third message being used to request at least one EDN, the at least one EDN deploying the EES requested by the terminal; and receive a response message from the SMF for the third message, the response message including information about the at least one first EDN.

[0401] Optionally, the third message includes information about alternative EDNs, which are determined by the first network element based on the location information of the terminal and the EDN information stored in the first network element.

[0402] Optionally, the third message may include the location information of the terminal.

[0403] Optionally, the information of the first EDN includes: the DNAI of the first EDN.

[0404] Optionally, the information from the first EDN is used to indicate the communication performance of the communication path between the terminal and the first EDN.

[0405] Optionally, the information of the first EDN may also include at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0406] Optionally, the communication unit 802A is also configured to send priority information of the at least one first EES to the terminal.

[0407] when Figure 8A The structural diagram shown is used to illustrate the structure of the SMF involved in the above embodiments:

[0408] Processing unit 801A is configured to receive a third message from a first network element via communication unit 802A, the third message being used to request at least one EDN; the at least one EDN deploys a MEC application instance requested by the terminal, or the at least one EDN deploys an EES requested by the terminal;

[0409] The processing unit 801A is further configured to send a response message of the third message to the first network element through the communication unit 802A according to the third message, wherein the response message includes information of at least one first EDN;

[0410] When at least one EDN deploys the MEC application instance requested by the terminal, the first EDN is the EDN that deploys the MEC application instance requested by the terminal; when at least one EDN deploys the EES requested by the terminal, the first EDN is the EDN that deploys the EES requested by the terminal.

[0411] Optionally, the at least one first EDN is determined based on the location information of the terminal and the information of at least one EDN obtained by the SMF.

[0412] Optionally, the at least one first EDN is determined based on the location information of the terminal and the information of the alternative EDNs, and the information of the alternative EDNs is carried in the third message.

[0413] Optionally, the location information of the terminal is carried in the third message.

[0414] Optionally, the information of the first EDN includes: the DNAI of the first EDN.

[0415] Optionally, the information from the first EDN is used to indicate the communication performance of the communication path between the terminal and the first EDN.

[0416] Optionally, the information of the first EDN may also include at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0417] The communication unit can also be called a transceiver unit. The antenna and control circuit with transceiver functions in the communication device 80A can be considered as the communication unit 802A of the communication device 80A, and the processor with processing functions can be considered as the processing unit 801A of the communication device 80A. Optionally, the device in the communication unit 802A used to implement the receiving function can be considered as a receiving unit. The receiving unit is used to execute the receiving steps in the embodiments of this application, and the receiving unit can be a receiver, a receiver circuit, etc. The device in the communication unit 802A used to implement the transmitting function can be considered as a transmitting unit. The transmitting unit is used to execute the transmitting steps in the embodiments of this application, and the transmitting unit can be a transmitter, a transmitter, a transmitting circuit, etc.

[0418] When using integrated units, Figure 8BA possible structural schematic diagram of the communication device (referred to as communication device 80B) involved in the above embodiments is shown. The communication device 80B includes a processing unit 801B and a communication unit 802B, and may also include a storage unit 803B. Figure 8B The structural diagram shown can be used to illustrate the structure of the first network element, the second network element, or the second SMF involved in the above embodiments.

[0419] when Figure 8B The structural diagram shown is used to illustrate the structure of the first network element involved in the above embodiments:

[0420] The communication unit 802B is used to obtain information of at least one first EDN from the second network element. The at least one first EDN is determined based on at least one of the terminal's location information or the terminal's service information. The second network element is a first session management network element or a NEF.

[0421] The processing unit 801B is configured to determine at least one first EES based on the information of the at least one first EDN.

[0422] The communication unit 802B is also used to send the address information of the at least one first EES to the terminal.

[0423] Optionally, the communication unit 802B is specifically used for:

[0424] Send a third message to the second network element, the third message including at least one of information for determining the location of the terminal or service information of the terminal;

[0425] The information of at least one first EDN is received from the second network element, wherein the first EDN matches at least one of the terminal's location information or the terminal's service information.

[0426] Optionally, the information of the first EDN includes: at least one DNAI of the first EDN.

[0427] Optionally, the information of the first EDN may also include at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0428] Optionally, the communication unit 802B is further configured to send priority information of the at least one first EES to the terminal.

[0429] when Figure 8B The structural diagram shown is used to illustrate the structure of the second network element involved in the above embodiments:

[0430] The processing unit 801B is configured to receive a third message from a first network element via the communication unit 802B. The third message includes at least one of information for determining the location of the terminal or service information of the terminal. The second network element is a first session management network element or a NEF.

[0431] The processing unit 801B is further configured to send at least one first EDN information to the first network element through the communication unit 802B according to the third message, wherein the first EDN matches at least one of the terminal's location information or the terminal's service information.

[0432] Optionally, the processing unit 801B is specifically used for:

[0433] The second session management network element is determined based on the location information of the terminal;

[0434] The communication unit 802B sends a request message to the second session management network element. The request message includes at least one of location information or service information. The location information includes the location information of the terminal, and the service information includes the service information of the terminal.

[0435] The communication unit 802B receives information from the at least one first EDN from the second session management network element;

[0436] The communication unit 802B sends the information of at least one first EDN to the first network element.

[0437] Optionally, the second network element is the NEF, and the processing unit 801B is specifically used for:

[0438] The information of the at least one first EDN is determined based on the location information of the terminal and a first correspondence relationship, wherein the first correspondence relationship includes the correspondence between location area information and EDN information; or...

[0439] The information of the at least one first EDN is determined based on the service information of the terminal and a second correspondence, wherein the second correspondence includes the correspondence between the service information and the EDN information; or...

[0440] The information of the at least one first EDN is determined based on the location information and service information of the terminal and a third correspondence relationship, wherein the third correspondence relationship includes the correspondence relationship between location area information, EDN information and service information;

[0441] The communication unit 802B sends the information of at least one first EDN to the first network element.

[0442] Optionally, the information of the first EDN includes: at least one DNAI of the first EDN.

[0443] Optionally, the information of the first EDN may also include at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

[0444] when Figure 8B The structural diagram shown is used to illustrate the structure of the second SMF involved in the above embodiments:

[0445] The communication unit 802B is used to receive a request message from a second network element. The request message includes at least one of location information and service information. The location information includes the location information of the terminal, and the service information includes the service information of the terminal. The second network element is a first session management network element or a NEF.

[0446] When the request message includes the location information, the processing unit 801B is configured to determine the information of the at least one first EDN based on the location information and a first correspondence relationship, wherein the first correspondence relationship includes the correspondence relationship between location area information and EDN information; or...

[0447] When the request message includes the service information, the processing unit 801B is configured to determine the information of the at least one first EDN based on the service information and a second correspondence, wherein the second correspondence includes the correspondence between the service information and the EDN information; or...

[0448] When the request message includes the location information and the service information, the processing unit 801B is configured to determine the information of the at least one first EDN based on the location information, the service information, and a third correspondence relationship, wherein the third correspondence relationship includes the correspondence relationship between location area information, EDN information, and service information.

[0449] The communication unit 802B is also used to send information about the at least one first EDN to the second network element.

[0450] The communication unit can also be called a transceiver unit. The antenna and control circuit with transceiver functions in the communication device 80B can be considered as the communication unit 802B of the communication device 80B, and the processor with processing functions can be considered as the processing unit 801B of the communication device 80B. Optionally, the device in the communication unit 802B used to implement the receiving function can be considered as a receiving unit. The receiving unit is used to execute the receiving steps in the embodiments of this application, and the receiving unit can be a receiver, a receiver circuit, etc. The device in the communication unit 802B used to implement the transmitting function can be considered as a transmitting unit. The transmitting unit is used to execute the transmitting steps in the embodiments of this application, and the transmitting unit can be a transmitter, a transmitter, a transmitting circuit, etc.

[0451] It should be understood that the division of units in the above device is merely a logical functional division. In actual implementation, they can be fully or partially integrated into a single physical entity, or they can be physically separated. Furthermore, all units in the device can be implemented entirely through software calls from processing elements; all units can be implemented entirely in hardware; or some units can be implemented through software calls from processing elements, and others in hardware. For example, each unit can be a separate processing element, or it can be integrated into a chip within the device. Alternatively, it can be stored as a program in memory, called and executed by a processing element of the device. Moreover, these units can be fully or partially integrated together, or implemented independently. The processing element mentioned here can also be called a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above units can be implemented through integrated logic circuits in the processor element or through software calls from processing elements.

[0452] In one example, a unit in any of the above devices can be one or more integrated circuits configured to implement the methods described above, such as: one or more application-specific integrated circuits (ASICs), or one or more digital signal processors (DSPs), or one or more field-programmable gate arrays (FPGAs), or a combination of at least two of these forms of integrated circuits. As another example, when a unit in the device can be implemented in the form of a processing element scheduler, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processor capable of calling programs. Furthermore, these units can be integrated together to implement a system-on-a-chip (SOC).

[0453] The receiving unit described above (e.g., a receiving unit) is an interface circuit of the device used to receive signals from other devices. For example, when the device is implemented as a chip, the receiving unit is an interface circuit for the chip to receive signals from other chips or devices. The transmitting unit described above (e.g., a transmitting unit) is an interface circuit of the device used to transmit signals to other devices. For example, when the device is implemented as a chip, the transmitting unit is an interface circuit for the chip to transmit signals to other chips or devices.

[0454] refer to Figure 9 This is a schematic diagram of the structure of a communication device (such as a terminal, a first network element, an SMF, a second network element, or a second SMF) provided in an embodiment of this application, used to implement the operation of the communication device in the above embodiments. Figure 9 As shown, the communication device includes a processor 910 and an interface 930, and optionally, a memory 920. The interface 930 is used to enable communication with other devices.

[0455] The methods executed by the communication device in the above embodiments can be implemented by the processor 910 calling a program stored in memory (which can be memory 920 in the communication device or external memory). That is, the device for the communication device can include the processor 910, which executes the methods executed by the communication device in the above method embodiments by calling a program in memory. The processor here can be an integrated circuit with signal processing capabilities, such as a CPU. The device for the communication device can be implemented by one or more integrated circuits configured to implement the above methods. For example: one or more ASICs, or one or more microprocessors (DSPs), or one or more FPGAs, or a combination of at least two of these integrated circuit forms. Alternatively, the above implementation methods can be combined.

[0456] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0457] The various illustrative logic units and circuits described in the embodiments of this application can be implemented or operate the described functions using a general-purpose processor, digital signal processor, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. The general-purpose processor can be a microprocessor; alternatively, it can also be any conventional processor, controller, microcontroller, or state machine. The processor can also be implemented using a combination of computing devices, such as a digital signal processor and a microprocessor, multiple microprocessors, one or more microprocessors combined with a digital signal processor core, or any other similar configuration.

[0458] In one or more exemplary designs, the functions described herein can be implemented in hardware, software, firmware, or any combination of these three. If implemented in software, these functions can be stored on a computer-readable medium or transmitted on a computer-readable medium in the form of one or more instructions or code. Computer-readable media includes computer storage media and communication media that facilitate the transfer of computer programs from one location to another. Storage media can be any available media accessible to a general-purpose or special-purpose computer. For example, such computer-readable media can include, but is not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage devices, or any other medium that can be used to carry or store program code in the form of instructions or data structures and other formats readable by a general-purpose or special-purpose computer or processor. Furthermore, any connection can be suitably defined as a computer-readable medium, for example, if the software is transmitted from a website, server, or other remote resource via a coaxial cable, fiber optic computer, twisted pair, digital subscriber line (DSL), or wirelessly, such as infrared, wireless, and microwave, it is also included in the definition of a computer-readable medium. The disks and discs mentioned include compressed disks, laser discs, optical discs, Digital Versatile Discs (DVDs), floppy disks, and Blu-ray discs. Disks typically copy data magnetically, while discs typically copy data optically using lasers. Combinations of these can also be contained in computer-readable media.

[0459] Those skilled in the art will understand that the various numerical designations, such as "first," "second," etc., used in this application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application, nor do they indicate a sequential order. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one" refers to one or more. "At least two" refers to two or more. "At least one," "any one," or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple. "Multiple" refers to two or more, and other quantifiers are similar.

[0460] Those skilled in the art will recognize that, in one or more of the examples above, the functions described in this application can be implemented using hardware, software, firmware, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of a computer program from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer.

[0461] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, or improvements made based on the technical solution of this application should be included within the scope of protection of this application. The above description in this application specification allows for the utilization or implementation of the content of this application by anyone skilled in the art. Any modifications based on the disclosed content should be considered obvious in the art. The basic principles described in this application can be applied to other variations without departing from the inventive nature and scope of this application. Therefore, the content disclosed in this application is not limited to the described embodiments and designs but can be extended to the maximum extent consistent with the principles and novel features disclosed in this application.

[0462] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely illustrative descriptions of the application as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Thus, if such modifications and modifications fall within the scope of the claims and their equivalents, this application is also intended to include such modifications and modifications.

Claims

1. A method for determining application instances, characterized in that, include: The first network element obtains information about at least one first edge data network (EDN) from the session management network element, wherein the at least one first EDN is determined based on the location information of the terminal. The first network element determines at least one first multi-access edge computing (MEC) application instance in the at least one first EDN; The first network element sends the address information of the at least one first MEC application instance to the terminal; The first network element obtains at least one piece of information about a first EDN from the session management network element, including: The first network element sends a third message to the session management network element, the third message being used to request at least one EDN, the at least one EDN having deployed the MEC application instance requested by the terminal; The first network element receives information from the session management network element regarding the at least one first EDN.

2. The method according to claim 1, characterized in that, The third message includes information about alternative EDNs, which are determined by the first network element based on the location information of the terminal and the EDN information stored in the first network element.

3. The method according to claim 1 or 2, characterized in that, The information of the first EDN includes: the Data Network Application Identifier (DNAI) of the first EDN.

4. The method according to claim 1 or 2, characterized in that, The method further includes: The first network element sends the address information of the edge enable server (EES) associated with the at least one first MEC application instance to the terminal, and the EES associated with the at least one first MEC application instance is deployed in the at least one first EDN.

5. The method according to claim 1 or 2, characterized in that, The information of the first EDN also includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

6. The method according to claim 1 or 2, characterized in that, The method further includes: The first network element sends priority information of the at least one first MEC application instance to the terminal.

7. A method for determining an Edge Enabled Server (EES), characterized in that, include: The first network element obtains information about at least one first edge data network (EDN) from the session management network element, wherein the at least one first EDN is determined based on the location information of the terminal. The first network element determines at least one first EES in the at least one first EDN; The first network element sends the address information of the at least one first EES to the terminal; The first network element obtains at least one piece of information about a first EDN from the session management network element, including: The first network element sends a third message to the session management network element. The third message is used to request at least one EDN. The at least one EDN is deployed with the EES requested by the terminal. The EES manages MEC application instances. The first network element receives information from the session management network element regarding the at least one first EDN.

8. The method according to claim 7, characterized in that, The third message includes information about alternative EDNs, which are determined by the first network element based on the location information of the terminal and the EDN information stored in the first network element.

9. The method according to claim 7 or 8, characterized in that, The information of the first EDN includes: the Data Network Application Identifier (DNAI) of the first EDN.

10. The method according to claim 7 or 8, characterized in that, The information of the first EDN also includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

11. The method according to claim 7 or 8, characterized in that, The method further includes: The first network element sends the priority information of the at least one first EES to the terminal.

12. A communication method, characterized in that, include: The session management network element receives a third message from the first network element, the third message being used to request at least one edge data network (EDN); The at least one EDN is deployed with a multi-access edge computing (MEC) application instance requested by the terminal, or the at least one EDN is deployed with an edge enable server (EES) requested by the terminal, and the EES manages the MEC application instance; The session management network element sends at least one first EDN information to the first network element according to the third message. The at least one first EDN information is used to determine the address information of at least one first MEC application instance, or the at least one first EDN information is used to determine the address information of at least one first EES. When at least one EDN deploys the MEC application instance requested by the terminal, the first EDN is the EDN that deploys the MEC application instance requested by the terminal; when at least one EDN deploys the EES requested by the terminal, the first EDN is the EDN that deploys the EES requested by the terminal.

13. The method according to claim 12, characterized in that, The at least one first EDN is determined based on the location information of the terminal and the information of at least one EDN obtained by the session management network element.

14. The method according to claim 12, characterized in that, The at least one first EDN is determined based on the location information of the terminal and the information of the candidate EDNs, and the information of the candidate EDNs is carried in the third message.

15. The method according to any one of claims 12-14, characterized in that, The information of the first EDN includes: the Data Network Application Identifier (DNAI) of the first EDN.

16. The method according to any one of claims 12-14, characterized in that, The information of the first EDN also includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

17. A method for determining an Edge Enabled Server (EES), characterized in that, include: The first network element obtains information about at least one first edge data network (EDN) from the second network element. The at least one first EDN is determined based on the terminal's service information. The second network element is a network open function (NEF). The first network element determines at least one first EES based on the information of the at least one first EDN; The first network element sends the address information of the at least one first EES to the terminal; The first network element obtains at least one piece of information about the first EDN from the second network element, including: The first network element sends a third message to the second network element, the third message including the service information of the terminal; the third message is used to request information from at least one first EDN, the at least one first EDN is deployed with an EES that matches the terminal request, and the EES manages MEC application instances; The first network element receives information from the second network element regarding the at least one first EDN, and the first EDN is matched with the service information of the terminal.

18. The method according to claim 17, characterized in that, The information of the first EDN includes: at least one data network application identifier (DNAI) of the first EDN.

19. The method according to claim 17 or 18, characterized in that, The information of the first EDN also includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

20. The method according to claim 17 or 18, characterized in that, The method further includes: The first network element sends the priority information of the at least one first EES to the terminal.

21. A communication method, characterized in that, include: The second network element receives a third message from the first network element. The third message includes the terminal's service information. The second network element is a Network Open Function (NEF). The third message is used to request information from at least one first edge data network (EDN), wherein the at least one first EDN is deployed with an EES that matches the terminal request, and the EES manages MEC application instances; the second network element sends the information from the at least one first EDN to the first network element according to the third message, wherein the first EDN matches the service information of the terminal, and the information from the at least one first EDN is used to determine the address information of at least one first EES.

22. The method according to claim 21, characterized in that, The second network element sends at least one piece of information about a first EDN to the first network element according to the third message, including: The second network element sends a request message to the second session management network element. The request message includes service information, which includes the service information of the terminal. The second network element receives information from the at least one first EDN from the second session management network element; The second network element sends the information of the at least one first EDN to the first network element.

23. The method according to claim 21, characterized in that, The second network element is the NEF, and the second network element sends at least one piece of information about a first EDN to the first network element according to the third message, including: The second network element determines the information of the at least one first EDN based on the service information of the terminal and the second correspondence relationship, wherein the second correspondence relationship includes the correspondence relationship between the service information and the EDN information; The second network element sends the information of the at least one first EDN to the first network element.

24. The method according to any one of claims 21-23, characterized in that, The information of the first EDN includes: at least one data network application identifier (DNAI) of the first EDN.

25. The method according to any one of claims 21-23, characterized in that, The information of the first EDN also includes at least one of the following: the number of user plane network elements between the terminal and the first EDN, the intra-mobile network communication latency between the terminal and the first EDN, the end-to-end communication latency between the terminal and the first EDN, the intra-mobile network communication bandwidth between the terminal and the first EDN, and the priority information of the communication path between the terminal and the first EDN.

26. A communication device, characterized in that, include: A functional unit for performing the method as described in any one of claims 1-6, or a functional unit for performing the method as described in any one of claims 7-11, or a functional unit for performing the method as described in any one of claims 12-16, or a functional unit for performing the method as described in any one of claims 17-20, or a functional unit for performing the method as described in any one of claims 21-25; The actions performed by the functional unit are implemented through hardware or through hardware executing corresponding software.

27. A communication device, characterized in that, include: processor; The processor is connected to a memory that stores computer execution instructions. The processor executes the computer execution instructions stored in the memory to cause the communication device to perform the following: Information about at least one first edge data network (EDN) is obtained from the session management network element, wherein the at least one first EDN is determined based on the terminal's location information; At least one first multi-access edge computing (MEC) application instance is determined in the at least one first EDN; Send the address information of the at least one first MEC application instance to the terminal; The step of obtaining information about at least one first edge data network (EDN) from the session management network element includes: A third message is sent to the session management network element, the third message being used to request at least one EDN, the at least one EDN having deployed the MEC application instance requested by the terminal; Receive information from at least one first EDN from the session management network element.

28. A communication device, characterized in that, include: processor; The processor is connected to a memory that stores computer execution instructions. The processor executes the computer execution instructions stored in the memory to cause the communication device to perform the following: Information about at least one first edge data network (EDN) is obtained from the session management network element, wherein the at least one first EDN is determined based on the terminal's location information; At least one first EES is determined in the at least one first EDN; Send the address information of the at least one first EES to the terminal; The step of obtaining information about at least one first edge data network (EDN) from the session management network element includes: A third message is sent to the session management network element, the third message being used to request at least one EDN, the at least one EDN deploying the EES requested by the terminal, the EES managing MEC application instances; Receive information from at least one first EDN from the session management network element.

29. A communication device, characterized in that, include: processor; The processor is connected to a memory that stores computer execution instructions. The processor executes the computer execution instructions stored in the memory to cause the communication device to perform the following: A third message is received from the first network element, the third message being used to request at least one edge data network (EDN); the at least one EDN is deployed with a multi-access edge computing (MEC) application instance requested by the terminal, or the at least one EDN is deployed with an edge enable server (EES) requested by the terminal, the EES managing the MEC application instance; According to the third message, at least one first EDN information is sent to the first network element, and the at least one first EDN information is used to determine the address information of at least one first MEC application instance, or the at least one first EDN information is used to determine the address information of at least one first EES. When at least one EDN deploys the MEC application instance requested by the terminal, the first EDN is the EDN that deploys the MEC application instance requested by the terminal; when at least one EDN deploys the EES requested by the terminal, the first EDN is the EDN that deploys the EES requested by the terminal.

30. A communication device, characterized in that, include: processor; The processor is connected to a memory that stores computer execution instructions. The processor executes the computer execution instructions stored in the memory to cause the communication device to perform the following: Information about at least one first edge data network (EDN) is obtained from the second network element, wherein the at least one first EDN is determined based on the terminal's service information, and the second network element is a network open function (NEF). At least one first EES is determined based on the information of the at least one first EDN; Send the address information of the at least one first EES to the terminal; The step of obtaining information about at least one first edge data network (EDN) from the second network element includes: A third message is sent to the second network element, the third message including the service information of the terminal; the third message is used to request information from the at least one first EDN, the at least one first EDN is deployed with an EES that matches the terminal request, and the EES manages MEC application instances; The terminal receives information from at least one first EDN from the second network element, wherein the first EDN is matched with the service information of the terminal.

31. A communication device, characterized in that, include: processor; The processor is connected to a memory that stores computer execution instructions. The processor executes the computer execution instructions stored in the memory to cause the communication device to perform the following: The third message is received from the first network element. The third message includes the terminal's service information. The communication device is a Network Open Function (NEF). The third message is used to request information from at least one first edge data network (EDN). The at least one first EDN is deployed with an EES that matches the terminal's request. The EES manages MEC application instances. The information of at least one first EDN is sent to the first network element according to the third message. The first EDN is matched with the service information of the terminal. The information of the at least one first EDN is used to determine the address information of at least one first EES.

32. A computer-readable storage medium, characterized in that, The method includes instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1-6, or the method as described in any one of claims 7-11, or the method as described in any one of claims 12-16, or the method as described in any one of claims 17-20, or the method as described in any one of claims 21-25.

33. A computer program product containing instructions, characterized in that, When the instructions are executed on a computer, the computer performs the method as described in any one of claims 1-6, or performs the method as described in any one of claims 7-11, or performs the method as described in any one of claims 12-16, or performs the method as described in any one of claims 17-20, or performs the method as described in any one of claims 21-25.

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