Method and apparatus for adjusting application context relocation in edge computing system

Abstract

The present disclosure relates to a communication technology for fusing a 5G communication system with an IoT technology to support a higher data rate than a 4G system, and a system therefor. The present disclosure may be applied to intelligent services (e.g., smart home, smart building, smart city, smart car or connected car, health care, digital education, retail, security and security-related services, etc.) on the basis of 5G communication technology and IoT-related technology. According to one embodiment of the present disclosure, there is provided a method performed by a source edge enabled server (EES) for application context relocation in a wireless communication system, the method comprising: receiving a user equipment (UE) serving application programming interface (API) context request including an edge enabled client (EEC) context ID and information about a subscription from a target EES; updating the subscription to a network exposure function (NEF) based on the information about the subscription; and sending the UE service API context response to the target EES.

Description

[0001] This application is a divisional application of a patent application for an invention named "Method and Apparatus for Adjusting Application Context Relocation in an Edge Computing System" with an international filing date of December 29, 2020, a Chinese application number of 202080091612.X. Technical Field

[0002] The present disclosure relates to a communication system and a method for enabling a terminal to use low-latency or broadband services. More specifically, the present disclosure relates to mobile edge computing (MEC), in which a terminal establishes a connection with an edge data network located nearby and accesses an edge computing platform operating in an edge enabler server (EES) of the corresponding edge data network or an application server running in an edge hosting environment to use data services. Background Art

[0003] The 4G communication system is now in commercial use, and in order to meet the growing demand for wireless data services, efforts are being made to develop an enhanced 5G communication system or a pre-5G communication system. Therefore, the 5G communication system or the pre-5G communication system is referred to as a super 4G network communication system or a post-LTE system. To achieve high data transmission rates, implementing the 5G communication system in the millimeter wave band (e.g., 60 GHz band) is being considered. To mitigate any path loss of radio waves in the millimeter wave band and increase the transmission distance of radio waves, technologies such as beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large antennas are being discussed for the 5G communication system. In addition, to enhance the network in the 5G communication system, technologies such as innovative small cells, advanced small cells, cloud radio access network (cloud RAN), ultra-dense network, device-to-device communication (D2D), wireless backhaul, mobile network, cooperative communication, coordinated multi-point (CoMP), and interference cancellation are being developed. In addition, hybrid frequency shift keying and quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC) as advanced coding modulation (ACM) methods; and filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as advanced access technologies are being developed for the 5G system.

[0004] Internet innovations have emerged from human - centered connected networks in which humans generate and consume information to the Internet of Things (IoT) networks that send, receive, and process information from and to distributed constituent elements such as things. Internet of Everything (IoE) technologies have emerged in which big data processing technologies connected to cloud servers are combined with IoT technologies. To implement IoT, technical elements such as sensing technologies, wired and wireless communication and network infrastructure, service interface technologies, and security technologies are required; thus, nowadays, research is being conducted on technologies for sensor networks, machine - to - machine (M2M), and machine - type communication (MTC) for connections between things. In the IoT environment, intelligent Internet technology (IT) services can be provided that collect and analyze data generated in connected things to provide new value to human life. Through the integration and complex connection between existing information technology (IT) and various industries, IoT can be applied to fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart appliances, and high - tech medical services.

[0005] Therefore, various attempts are being made to apply 5G communication systems to IoT networks. For example, 5G communication technologies such as sensor networks, machine - to - machine (M2M), and machine - type communication (MTC) have been implemented through technologies such as beamforming, MIMO, and array antennas. The application of cloud RAN, which is the aforementioned big data processing technology, can be an example of the integration of 5G technology and IoT technology. SUMMARY OF THE INVENTION

[0006] TECHNICAL PROBLEM

[0007] The present disclosure provides a method for performing application context relocation between edge access servers (EASs) for service continuity in an edge - computing system. In a case where it is necessary to change the EAS that provides edge - computing services to a terminal, the process of transferring the application context from a source EAS to a target EAS can be triggered by several devices (e.g., an edge - edge server (EES), or an edge - enabler client (EEC) in the terminal, and an application client). However, since the process of transferring the application context may be initiated simultaneously by multiple devices, a method capable of coordinating this process needs to be designed.

[0008] More specifically, in the absence of a method for coordinating the application context relocation process initiated by the simultaneous triggering of multiple devices, the signaling generated due to this process may be repeatedly sent and received between devices, resulting in a load on the system. For example, in the case where a terminal does not recognize that an application context relocation process is being triggered and processed (in-progress) by another device in the network, the terminal triggers the application context relocation process, leading to additional consumption of radio resources. Additionally, in some of the various edge computing deployment scenarios based on the movement of the terminal, in the case where the terminal leaves the service area of the source edge data network, communication with the source EEC and source EAS may be impossible. In such a case, in order for the relocated terminal to receive data services, it is necessary to design a method for initiating the application context relocation process in the source edge data network (which may refer to a network including the source EES and source EAS) and enabling the terminal to know whether the process has been completed.

[0009] In addition, the present disclosure provides a method for obtaining information about a terminal using edge computing services through the Third Generation Partnership Project (3GPP) (e.g., UE service application programming interface (API) acquisition). Specifically, the present disclosure proposes a method for obtaining information about a terminal when the terminal using edge computing services moves. That is, the present disclosure will reduce overhead according to the operation to be performed, so as to obtain the information required for edge computing services through the 3GPP system when the terminal moves, and provide the corresponding information while maintaining continuity. More specifically, the edge computing system can obtain the information required to provide edge computing services to the terminal through the 3GPP system. To this end, the Edge Enablement Server (EES) subscribes to the Network Exposure Function (NEF), which is one of the 3GPP network functions (NFs), and the NEF subscribes to receive information about the target terminal from other 3GPP NFs, so as to receive information about the terminal from the 3GPP system. However, in the case of terminal movement, there may be an overhead in the 3GPP system that should repeat subscription / unsubscription to obtain information. That is, it may be necessary to repeatedly perform subscription / unsubscription configuration between the NF that exposes terminal-related information to the edge computing device (e.g., EES) and the NF that provides terminal-related information. For example, when the terminal moves from the service area of the source EES to the service area of the target EES, the continuity of obtaining terminal-related information (e.g., location information or terminal identification information, etc.) through the 3GPP system is cut off. This is because the EES that subscribes to the NF (e.g., NEF) that exposes the corresponding UE-related information changes according to the movement of the UE. Taking the 5G system as an example, the existing source EES can perform an operation (unsubscription) to cancel the event exposure subscription to the NEF for the corresponding terminal, and the NEF can cancel the subscription to receive relevant information from another 3GPP NF. Therefore, it is necessary to design a method that can solve the problem of repeated subscription and unsubscription configuration between NFs caused by the movement of the terminal.

[0010] Solution to the problem

[0011] To solve the above problems, according to an embodiment of the present disclosure, there is provided a method performed by a source edge enablement server (EES) relocated by application context in a wireless communication system, the method including: receiving, from a target EES, a user equipment (UE) service application programming interface (API) context request including an edge enablement client (EEC) context ID and information about a subscription; updating a subscription to a network exposure function (NEF) based on the information about the subscription; and sending a UE service API context response to the target EES.

[0012] In addition, according to an embodiment of the present disclosure, there is provided a method performed by a target Edge Enablement Server (EES) for application context relocation in a wireless communication system. The method includes: sending a User Equipment (UE) service Application Programming Interface (API) context request including an Edge Enablement Client (EEC) context ID and information about a subscription to a source EES; and receiving a UE service API context response from the source EES, wherein an update of a subscription to a Network Exposure Function (NEF) is performed by the source EES based on the information about the subscription.

[0013] In addition, according to an embodiment of the present disclosure, there is provided a source Edge Enablement Server (EES) for application context relocation in a wireless communication system. The source EES includes: a transceiver; and a controller coupled to the transceiver and configured to: receive a User Equipment (UE) service Application Programming Interface (API) context request including an Edge Enablement Client (EEC) context ID and information about a subscription from a target EES, update a subscription to a Network Exposure Function (NEF) based on the information about the subscription, and send a UE service API context response to the target EES.

[0014] In addition, according to an embodiment of the present disclosure, there is provided a target Edge Enablement Server (EES) for application context relocation in a wireless communication system. The target EES includes: a transceiver; and a controller coupled to the transceiver and configured to: send a User Equipment (UE) service Application Programming Interface (API) context request including an Edge Enablement Client (EEC) context ID and information about a subscription to a source EES, and receive a UE service API context response from the source EES, wherein an update of a subscription to a Network Exposure Function (NEF) is performed by the source EES based on the information about the subscription.

[0015] In addition, according to an embodiment of the present disclosure, there is provided a method for a first server in a wireless communication system. The method for the first server includes: receiving first information about whether an application context relocation process can be initiated from at least one of a terminal or an application server; identifying second information related to the application context relocation process based on the first information; sending the second information to the terminal and the application server; and sending an indication that the application context relocation process is in progress to the terminal and the application server when it is recognized that the application context relocation process is being performed.

[0016] In addition, according to an embodiment of the present disclosure, there is provided a method for a terminal in a wireless communication system. The method for the terminal includes: sending first information about whether an application context relocation process can be initiated to a first server; receiving second information related to the application context relocation process from the first server; and identifying whether to initiate the application context relocation process based on the second information, wherein the second information is identified based on the first information.

[0017] In addition, according to an embodiment of the present disclosure, a first server of a wireless communication system is provided. The first server includes: a transceiver; and a controller configured to control the transceiver to: receive first information regarding whether an application context relocation process can be initiated from at least one of a terminal or an application server, identify second information related to the application context relocation process based on the first information, control the transceiver to send the second information to the terminal and the application server, and control the transceiver to send an indication that the application context relocation process is in progress to the terminal and the application server when it is recognized that the application context relocation process is being executed.

[0018] In addition, according to an embodiment of the present disclosure, a terminal of a wireless communication system is provided. The terminal includes: a transceiver; and a controller configured to: control the transceiver to send first information regarding whether an application context relocation process can be initiated to a first server, control the transceiver to receive second information related to the application context relocation process from the first server, and identify whether to initiate the application context relocation process based on the second information, wherein the second information is identified based on the first information.

[0019] Advantageous Effects of the Invention

[0020] According to an embodiment of the present disclosure, in a wireless communication system, the EES can select an application context relocation mode based on the capabilities of the EEC and the EAS, and thus, the application context relocation process can be performed.

[0021] In addition, according to an embodiment of the present disclosure, a method for preventing multiple devices from repeatedly initiating an application context relocation process is provided, thereby reducing the overhead caused by unnecessary signaling.

[0022] In addition, according to an embodiment of the present disclosure, even in a deployment scenario where communication with the EES and the EAS in the source edge data network is no longer possible due to the movement of the terminal, a method for notifying the terminal that the application context relocation process has been completed is provided; thus, the application context relocation process can be performed more stably.

[0023] In addition, according to an embodiment of the present disclosure, a method for minimizing the operation overhead that occurs between other 3GPP NFs and an NF that provides terminal-related information available through the 3GPP system to an edge computing system according to changes in the EES / EAS for providing edge computing services according to the movement of the terminal is provided. Specifically, a method for minimizing the duplication of subscription / cancellation subscription configurations between a 3GPP NF that can minimize the exposure of terminal-related information to an edge computing device (e.g., the EES) and a 3GPP NF that provides terminal-related information is provided.

[0024] The effects achievable in the present disclosure are not limited to the above effects, and other effects not mentioned will be clearly understood by those of ordinary skill in the art to which the present disclosure pertains from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following description of embodiments of the present disclosure with reference to the accompanying drawings.

[0026] Figure 1 is a diagram showing an example of an implementation scenario of an edge computing system to which embodiments of the present disclosure can be applied.

[0027] Figure 2 is a message flow diagram showing a method for selecting an application context relocation mode among EEC, EES, and EAS in a terminal according to an embodiment of the present disclosure.

[0028] Figure 3 is a message flow diagram showing an embodiment of performing coordination during an application context relocation process according to the present disclosure.

[0029] Figure 4 is a message flow diagram showing an embodiment of performing coordination during an application context relocation process according to the present disclosure.

[0030] Figure 5 is a flowchart showing the operation of a source EES according to an embodiment of the present disclosure.

[0031] Figure 6 is a flowchart showing the operation of a target EES according to an embodiment of the present disclosure.

[0032] Figure 7 is a message flow diagram showing operations that can be performed for coordination during an application context relocation process according to an embodiment of the present disclosure.

[0033] Figure 8 is a message flow diagram showing operations that can be performed for coordination during an application context relocation process according to an embodiment of the present disclosure.

[0034] Figure 9 is a block diagram showing the structure of a server according to the present disclosure.

[0035] Figure 10 is a block diagram showing the structure of a terminal according to the present disclosure.

[0036] Figure 11 is a flowchart showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0037] Figure 12It is a message flow diagram showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0038] Figure 13 It is a message flow diagram showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0039] Figure 14 It is a message flow diagram showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0040] Figure 15 It is a message flow diagram showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0041] Figure 16 It is a message flow diagram showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0042] Figure 17 It is a block diagram showing a method in which a source EES subscribes to a NEF to obtain terminal information according to an embodiment of the present disclosure.

[0043] Figure 18 It is a block diagram showing the structure of a server according to an embodiment of the present disclosure.

[0044] Figure 19 It is a block diagram showing the structure of a terminal according to an embodiment of the present disclosure. Detailed Description of the Invention

[0045] Hereinafter, the operation principle of the present disclosure will be described in detail with reference to the accompanying drawings. The terms to be described later are terms defined in consideration of the functions in the present disclosure. Since this may vary according to the intention or habit of the user or operator, the definition should be determined according to the content of the entire specification.

[0046] For ease of description, terms indicating network entities and entities of an edge computing system, terms indicating messages, and terms indicating identification information used in the present disclosure are illustrated. Therefore, the present disclosure is not limited to the terms described below, and other terms indicating objects having equivalent technical meanings may be used.

[0047] Hereinafter, for convenience, the present disclosure uses terms and names defined in the 5G system standard, but is not limited to these terms and names, and can be equivalently applied to systems conforming to other standards.

[0048] In edge computing services, the UE service API is an API required to obtain and provide terminal-related information necessary for providing edge computing services, and the UE service API context information of the present disclosure may include at least one of the following items.

[0049] - The ID, address, and subscription-related ID of the NF that exposes the corresponding terminal information (e.g., NEF, service capability exposure function (SCEF)), which can be a reference ID that identifies the event of the NF in which the edge computing device is exposed, the S-NSSAI of the slice to which the corresponding NF belongs, the event ID supported by the application function, or the information for NEF discovery (such as the domain name).

[0050] - Information about the terminal: UE ID (e.g., GPSI, external identifier, external group identifier), EEC ID, UE IP address.

[0051] - Application-related information for which the terminal is receiving services: Application ID (application client ID) for receiving edge computing services, EAS ID / address that provides edge computing services, EAS instance ID, or edge computing service provider information.

[0052] In the present disclosure, a term used as a function may represent a device that performs the function.

[0053] In the present disclosure, the source edge enabling server may be referred to as the source EES, S-EES, the first server, etc., and may be referred to by terms having the same or similar meanings. Hereinafter, the source edge enabling server will be referred to as the source EES.

[0054] In the present disclosure, the source edge application server may be referred to as the source EAS, S-EAS, etc., and may be referred to by terms having the same or similar meanings. Hereinafter, the source edge application server will be referred to as the source EAS.

[0055] In the present disclosure, the target edge enabling server may be referred to as the target EES, object EES, T-EES, the second server, etc., and may be referred to by terms having the same or similar meanings. Hereinafter, the target edge enabling server will be referred to as the target EES.

[0056] In the present disclosure, the target edge application server may be referred to as the target EAS, T-EAS, etc., and may be referred to by terms having the same or similar meanings. Hereinafter, the target edge application server will be referred to as the target EAS.

[0057] Furthermore, in the present disclosure, the edge enabling client may be referred to as the EEC, the EEC in the terminal, the terminal, etc., and may be referred to by terms having the same or similar meanings. Hereinafter, the edge enabling client will be referred to as the EEC.

[0058] Figure 1It is a diagram showing an example of an implementation scenario of an edge computing system to which embodiments of the present disclosure can be applied.

[0059] A user plane function (UPF) (or a network entity capable of executing the UPF) can act as a gateway for transmitting packets to be sent and received. To support edge computing services, the EES can be placed close to the UPF. The UPF directly sends data packets to the edge data network without passing through the Internet, enabling low-latency transmission. The UPF can also be connected to a data network connected to the Internet.

[0060] An edge computing system to which the present disclosure can be applied can include an EES, an edge data network configuration server, and an EEC. The EES can build an edge hosting environment (or an edge computing platform) and know information about the EAS running in the edge hosting environment.

[0061] The EES can perform a function of negotiating with the UE to connect the application client of the UE and the EAS in the edge hosting environment. The UE supporting the edge computing system can have a built-in EEC, and the negotiation between the UE and the EES can be performed through the interaction between the EEC and the EES. The layer that performs the interaction (such as negotiation) between the EEC and the EES can be referred to as the edge enabling layer. The UE mentioned in the present disclosure can include all UEs capable of performing wireless communication, such as Internet of Things (IoT) devices, vehicles, drones, robots, and smartphones.

[0062] The edge data network configuration server knows the deployment information of the EES and can perform a function of transmitting configuration information for using edge computing services to the UE. The configuration information can include at least one of edge data network connection information (e.g., data network name, S-NSSAI, etc.), edge data network service area (e.g., cell list, tracking area list, PLMN ID), or EES connection (edge enabling server connection) information (e.g., URI). That is, the UE can identify (or obtain) information about the accessible EES at a specific location. When the edge data network configuration server can know information about the EAS running in the edge hosting environment of a specific EES, the UE can also obtain the corresponding information through the EEC.

[0063] The EAS refers to a third-party application server running in the edge computing system. The EAS is a third-party application server running in the infrastructure provided by the edge hosting environment. Since the EAS can provide services at a location close to the UE, the EAS can provide ultra-low latency services to the UE. In the EAS, information about the upper layer of the service provided to the UE can be referred to as the application context.

[0064] For example, when a user uses a real-time gaming application, all the information required to regenerate the currently displayed screen and the game stage according to the usage of the gaming application can be included in the application context. The application context can be relocated to the EAS to be newly connected, so that the UE can connect to another EAS to seamlessly use the existing services. To perform application context relocation, the EAS that can provide services to the application running in the application client of the UE should be available. The availability of the EAS in the edge data network can be determined based on whether the EAS is driven in the edge hosting environment and the status of the EAS.

[0065] The UE may include an application client, an EEC for enabling the application client to interact with the edge computing service, and a mobile terminal (MT) for accessing the mobile communication system.

[0066] The UE application is an application provided by a third party and may refer to a client application program running in the UE for a specific application service. Several applications can be driven in the UE. At least one of the various applications can use the mobile edge computing (MEC) service.

[0067] The EEC in the UE may refer to a client that performs operations required to use the edge computing service in the UE. The EEC can perform operations to determine which applications can use the edge computing service and connect the network interface, so that the data of the application client in the UE can be sent to the EAS that provides the edge computing service.

[0068] The operation for establishing a data connection to use the edge computing service can be performed by the MT in the UE in the 3rd Generation Partnership Project (3GPP) communication layer. The 3GPP communication layer may refer to a layer that performs operations for using the mobile communication system (e.g., modem operations) and performs at least one of the roles of establishing a wireless connection for data communication, registering the UE in the mobile communication system, establishing a connection for data transmission to the communication system, and sending and receiving data.

[0069] The following will refer to Figure 2 Describe a method for determining (identifying) the requirements for performing application context relocation and a method for determining the target EES or target EAS in the above-mentioned edge computing system.

[0070] Figure 2 Is a message flow diagram showing a method for selecting an application context relocation mode among the EEC, EES, and EAS in the UE according to an embodiment of the present disclosure.

[0071] Refer to Figure 2, in step 1A, the EEC in the UE can notify the EES of the UE's application context relocation initiation UE capability. That is, the EEC can send the EES the capability information on whether the UE can initiate the application context relocation process.

[0072] When the EEC performs the registration process with the EES (EEC registration process) (which can include the initial registration process and the registration update process), or when the EEC sends a registration request to the EES, the operation of sending the capability information can be performed. That is, the EEC can include and send the capability information in the registration request or in the message sent to the EES during the registration process. Alternatively, the operation of sending the capability information can be performed immediately after the application client is executed through a separate process.

[0073] ● In the operation of sending the capability information, the EEC can identify whether the application client and the MT in the UE can initiate the application context relocation process and send it to the EES. The UE's application context relocation initiation UE capability according to the present disclosure can include at least one of the following information.

[0074] - Whether the application context relocation of the UE can be initiated

[0075] - Information or required information that can be considered when determining whether to initiate the application context relocation process (e.g., the edge data network service area), the required application key performance indicators (or QoS)

[0076] - The estimated time required to perform the application context relocation initiation operation

[0077] In addition, in step 1B, the EAS can notify the EES of the application context relocation initiation EAS capability. That is, the EAS can send the EES the capability information on whether it can initiate the application context relocation process.

[0078] When the EAS performs the registration process with the EES (EAS registration process) (which can include the initial registration process and the registration update process), or when the EAS sends a registration request to the EES, the operation of sending the capability information can be performed. Alternatively, the operation of sending the capability information can be performed as a separate operation after receiving the notification for EEC registration from the EES.

[0079] ● In the operation of sending the capability information, the EAS can identify whether it can initiate the application context relocation process and send it to the EES. The application context relocation initiation EAS capability according to the present disclosure can include at least one of the following information.

[0080] - Whether the EAS can initiate the application context relocation

[0081] - Information or required information that can be considered when determining whether to initiate an application context relocation process

[0082] ■ Whether to subscribe to user plane (UP) management event notifications, or whether it is possible to subscribe to user plane (UP) management event notifications

[0083] ■ Whether it is possible to serve the application client (e.g., whether to initiate application context relocation for load balancing based on load, key performance indicators of the required application (required application KPI) (or QoS))

[0084] - Estimated time required to perform the application context relocation initiation operation

[0085] In step 1A or 1B, in order for the EEC or EAS to delegate the initiation of the application context relocation process rather than the ability to initiate the application context relocation to the EES, the EEC or EAS may send a delegation request for application context relocation initiation to the EES. Once the delegation request is received, the EES may perform pre-operations to determine whether an application context relocation process needs to be initiated. The pre-operations may include the EES sending a subscription request for relevant event notification services to the network exposure function (NEF) to track the UE's location or monitor user plane path management events.

[0086] In step 2, the EES may select (or determine) an application context relocation mode (hereinafter referred to as the relocation mode) based on the application context relocation initiation UE capabilities and application context relocation initiation EAS capabilities received from the EEC and EAS respectively.

[0087] In the present disclosure, the relocation mode may refer to information including information about the entity initiating the application context relocation process and information about the conditions for initiating the application context relocation process, and operate based on this information. That is, the EES, EAS, and EEC can identify whether they can initiate the application context relocation process according to the selected relocation mode, and are configured to operate according to the conditions capable of initiating the process.

[0088] The EES can determine the relocation mode based on a predefined method or information without receiving the capability information of the UE or EAS (e.g., in the case where the EES already knows the capability information of the UE or EAS based on this information). For example, the EES can receive relevant information from the edge data network configuration server without receiving the capability information from the EEC and EAS. To enable the EEC to receive the edge data network configuration information, the EEC can provide the capability information of the EEC while sending an initial provisioning request to the edge data network configuration server, and the edge data network configuration server can send this information to the EES to which the EEC will connect. The corresponding information can be sent before the EEC connects to the EES. This is because the edge data network configuration server can know the EES to which the EEC will connect based on the application client-related information and UE-related information provided by the EEC (e.g., connection information such as a public local mobile network ID, or the location information of the UE).

[0089] In the present disclosure Figure 2 An embodiment is shown in which the EES selects a relocation mode based on the information about the capabilities of the UE received from the EEC and the information about the capabilities of the EAS received from the EAS, but the present disclosure is not limited thereto. That is, the EES can select a relocation mode based on the information about the UE capabilities from the EEC, or can select a relocation mode based on the information about the EAS capabilities received from the EAS.

[0090] The relocation mode can be configured for each UE, for each application (e.g., different modes can be configured for each EAS), or for each EES (therefore, the configuration information about the EAS registered in the EES can be the same). Hereinafter, the method for the EES to select a relocation mode will be described.

[0091] ● The EES can determine which device is allowed to initiate the application context relocation process based on the information about the application context relocation initiation capabilities of the received UE or EAS. However, the device allowed to initiate this process is not limited to one. In this case, when selecting a relocation mode, the EES can consider its application context relocation initiation capabilities to determine.

[0092] ■ Initiation can be allowed from multiple devices. This is to cope with the situation where application context relocation is required according to various circumstances (e.g., it can include the situation where application context relocation is required due to the loss of the service providing capabilities of the EAS and the situation where application context relocation is required due to the location movement of the UE). In this case, to quickly execute the application context relocation process, the EES can select a relocation mode that allows both the UE and the EAS to initiate this process.

[0093] ■The EES can configure the conditions under which each of the UE and the EAS should initiate application context relocation and the initiation conditions of the application context relocation process, as shown in the following examples (however, the present disclosure is not limited to the examples presented below).

[0094] -Example 1) The EEC performs initiation based on leaving the service area, and the EAS performs initiation because application client services cannot be provided according to the load.

[0095] -Example 2) The EEC performs initiation based on leaving the service area, and the EES performs application context relocation due to abnormal termination or abnormality of the EAS. In this case, the EAS can prohibit the initiation.

[0096] -Example 3) The EEC and the EES perform application context relocation based on leaving the service area, and the EAS performs initiation due to service unavailability.

[0097] In step 3, the EES can notify the EEC and the EAS of the configured or coordinated relocation mode. In the case where the relocation mode is configured differently for each UE, the EES can include information capable of identifying the UE or the EEC in the UE (for example, UE ID, UE IP address, or EEC ID). In this case, the relocation mode can be notified as shown in the following examples. However, the following examples are given as examples in the embodiments of the present disclosure, and the present disclosure is not limited thereto. That is, the EES can notify the UE and the EAS of the relocation mode based on various methods.

[0098] ●Example 1) In the case where it is possible to send only whether to allow the initiation of the application context relocation process, it is possible to send regarding whether to allow all of each device (for example, {EEC: O, EES: X, EAS: O}), or it is possible to send whether to allow only the device that receives whether to allow (for example, {O} or {X}) to initiate.

[0099] ●Example 2) It is also possible to send whether to allow the initiation of the application context relocation process and the conditions to be considered (see the examples in step 2).

[0100] In step 4A, the EEC can configure the relocation mode by reflecting the information received from the EES. For example, the EEC can continue or may not perform the operation of comparing the UE's location information with the service area of the EES. Alternatively, the EEC can determine whether to perform monitoring or reporting operations on the relocation requirements from the application client and the modem in the UE (i.e., the conditions considered to initiate the application context relocation process). That is, according to the relocation mode, the EES can identify whether it can initiate the application context relocation process and perform operations accordingly. The EEC can send the configuration information about the relocation mode received from the EES to the application client and the MT in the UE. In this case, the application client and the MT can additionally perform configurations related to the initiation of the application context relocation process.

[0101] In step 4B, the EES can determine which device to send the relocation in - progress indication to. That is, the EES can determine the device to which the relocation in - progress indication is to be sent. The EES can identify the device capable of initiating the application context relocation process based on the configured relocation mode, thereby reducing the transmission of unnecessary relocation in - progress indications.

[0102] That is, the EES sends the relocation in - progress indication to the device capable of initiating the application context relocation process to notify that the process is in progress to prevent redundant operations, and does not send the relocation in - progress indication to the device that cannot initiate the application context relocation process, thereby reducing the signaling overhead caused by sending unnecessary relocation in - progress indications.

[0103] In the case where the EEC newly connects to the target EES, the EEC can provide the information about the relocation mode received from the previous source EES to the target EES. In this case, the detailed description of the relocation in - progress indication is as follows.

[0104] ● Relocation in - progress indication: In the case where multiple devices are allowed to initiate the application context relocation process, the relocation in - progress indication is a message (or indication) to be sent (transmitted) to notify another device that a process for context relocation has been initiated by one device to prevent duplicate processes. The relocation in - progress indication can include information about the device that initiated the relocation process and information indicating that the process for context relocation has been initiated.

[0105] ● The EES can subscribe to or cancel the user - plane path management event notification of the corresponding UE according to the determined relocation mode. In this case, the EES can refer to the newly connected target EES.

[0106] ● In the case where the fact that a new UE has entered the service area of the target EES is recognized according to the determined relocation mode, the target EES may determine whether to notify the source EES to which the UE was previously connected that the UE has moved to its service area. (For example, in the case where the UE is allowed to initiate a relocation process, the target EES may recognize through the EEC registration process that the UE has moved to its service area and notify the source EES of this fact.)

[0107] In step 4C, the EAS may subscribe to or cancel the user plane management event notification for the corresponding UE based on the relocation mode received from the EES.

[0108] Hereinafter, the process of performing the application context relocation process according to the present disclosure based on the above relocation mode will be described.

[0109] Figure 3 is a message flow diagram showing an embodiment of performing coordination in the application context relocation process according to the present disclosure.

[0110] Refer to Figure 3 , Figure 3 is a message flow diagram showing an embodiment of performing the application context relocation process in a deployment scenario where the communication range between the UE and the source EES is restricted to the service area of the source EES.

[0111] This embodiment can be applied to all scenarios where the UE can no longer communicate with the source EES after initiating the application context relocation process based on the source EES.

[0112] For example, in the case where the source EES (or source EAS) initiates the application context relocation process and the UE moves to the service area of the target EES before the process is completed, this embodiment can be applied. It will be described in detail below.

[0113] Refer to Figure 3 ,in step 0, the source EES or source EAS may initiate the application context relocation process. As described above, the UE may move to the service area of the target EES. This embodiment can be applied even in the case where the UE moves at any point in time before the relocation process is completed.

[0114] In step 1, the source EES or source EAS may send an in - relocation indication to each device based on the configured relocation mode. In this case, the relocation mode may be configured according to the above - described method referred to Figure 2 . Alternatively, the relocation mode may be pre - configured for the EES. Alternatively, in the case where the EES or EAS knows the capabilities of each device, the relocation mode may be configured without Figure 2Exchange individual capability information, and the EES or EAS may send an in - relocation indication to the determined device according to the configured relocation mode. For a detailed description, refer to the above description.

[0115] In this case, the source EES or source EAS only sends an in - relocation indication to the devices (e.g., EEC or (multiple) source EAS) that are allowed to initiate the application context relocation process in the relocation mode (e.g., the relocation mode selected (determined) by the source EES), thereby reducing signaling overhead. However, in the case where no relocation mode is configured, the source EES or source EAS may send an in - relocation indication to all devices. In this case, all devices may include the devices (EEC, EAS) belonging to the service area of the source EES or other EESs.

[0116] ● The in - relocation indication may include information indicating that the corresponding application context relocation process is already in progress. In addition, the indication may include information about which application context relocation of the UE is in progress (e.g., application ID or EAS (instance) ID). In addition, the in - relocation indication sent to the source EAS may include information capable of identifying the UE or EEC (e.g., EEC ID, UE ID, UE IP address, or ID assigned from the authentication and authorization function).

[0117] As described above, in the case where the UE is not allowed to initiate the application context relocation process, the EES or EAS does not send the above - mentioned in - relocation indication to the EEC of the corresponding UE, thereby reducing signaling overhead.

[0118] In addition, the source EES may notify other source EASs about the application context relocation process initiated from the source EAS through the in - relocation indication, thereby preventing the initiation of redundant processes.

[0119] In step 2, the EEC in the UE may perform a registration process with the target EES. In the case where the EEC does not perform the registration process, the EEC may notify the target EES of its movement to the target EES service area through separate signaling.

[0120] In step 3, the target EES may send an EEC registration event notification to the source EES. In this case, the target EES may send the EEC registration event notification by including information capable of identifying the UE or the EEC in the UE. The information capable of identifying the UE or the EEC in the UE may refer to, for example, EEC ID, UE ID, UE IP address, or ID assigned from the authentication and authorization function.

[0121] In step 4, the target EES may send an in - relocation indication to the EEC.

[0122] ● That is, to prevent the application context relocation process from being initiated in the UE, the target EES can send a relocation in progress indication to the UE. For example, in the case where the indication is not sent in step 1 according to specific conditions (e.g., when the UE leaves the service area of the source EES before sending the indication), the target EES can send the indication to the UE. Alternatively, regardless of whether the operation in step 1 is performed, the target EES can send the indication to the UE.

[0123] ● The relocation in progress indication can include information indicating that the process is already in progress, and also include information about which application context relocation of the UE is in progress. (e.g., application ID or EAS (instance) ID).

[0124] In operation A, the source EES can determine whether the UE has left its service area based on the EEC registration event notification received from the target EES. In the case where the UE leaves the service area of the source EES, the UE can perform an EEC deregistration operation after the application context relocation process for the UE is completed.

[0125] In operation B, the UE can coordinate the relocation mode.

[0126] Even if the previously configured initiation conditions for the application context relocation process are met, the UE can coordinate the relocation mode based on the relocation in progress indication received from the target EES so as not to initiate the process. The coordination operation can be applied to each application client, or can be applied jointly to all running application clients. This can be determined according to the EAS information and the application included in the relocation in progress indication.

[0127] In operation C, the target EES rather than the source EES can perform AF impact on the traffic routed to the target EAS where the application context relocation for the application data traffic has been completed. This is because the source EES may no longer perform application function requests to affect the UE's traffic routing. Alternatively, the target EES can notify the UE of the completion of the application context relocation process in the EEC and enable the EEC to perform application data traffic rerouting.

[0128] Figure 4 is a message flow diagram showing an embodiment in which coordination is performed during the application context relocation process according to an embodiment of the present disclosure.

[0129] Figure 4 is a message flow diagram showing the process of performing the application context relocation process in a deployment scenario where the communication range between the UE and the source EES is restricted to the service area of the source EES.

[0130] This embodiment can be applied to all scenarios where the UE can no longer communicate with the source EES after the application context relocation process based on the source EES is initiated.

[0131] Specifically, in step 0, the UE or the EEC in the UE can initiate an application context relocation process to send a context relocation request (or context relocation request message, application context relocation request, application context relocation request message) to the source EES. However, before this process is completed, the UE can move to the target EES service area, and in this case, this embodiment can be applied. Even if the UE moves at any point in time before the relocation process is completed, this embodiment can still be applied.

[0132] In step 1, the source EES can send an in - relocation indication to the source EAS that provides services to the UE. Specifically, the source EAS can identify the device (e.g., the source EAS) that sends the indication according to the configured relocation mode. The method of configuring the relocation mode is the same as described above and will be omitted below.

[0133] The in - relocation indication can include information capable of identifying the UE or the EEC in the corresponding UE (e.g., at least one of the EEC ID, UE ID, UE IP address, or the ID assigned from the authentication and authorization function). By receiving a context relocation request (or context relocation request message, application context relocation request, application context relocation request message) from the UE (or EEC), the source EES can recognize that the process has been initiated in the EEC. The context relocation request can be sent from the UE to the source EES before step 0 or 1.

[0134] In step 2, the EEC in the UE can perform a registration process with the target EES. In the case where the EEC does not perform the registration process, the EEC in the UE can notify the target EES through separate signaling that it has moved to the target EES service area.

[0135] Since the EEC has sent a context relocation request to the source EES, the EEC will not immediately perform the same operation (the operation of sending a context relocation request) on the target EES. That is, the EEC can refrain from sending a context relocation request to the target EES until it knows that the application context relocation process has failed or until a predefined timer expires.

[0136] The EEC can send the information about the relocation mode received from the source EES to the target EES through the registration process or a separate process.

[0137] In step 3, the target EES can send an EEC registration event notification to the source EES.

[0138] ● The target EES may include information capable of identifying the UE or the EEC in the UE to send an EEC registration notification to the source EES. For example, the information capable of identifying the EEC may include at least one of an EEC ID, a UE ID, a UE IP address, or an ID assigned from an authentication and authorization function.

[0139] In step 4, the source EES may coordinate the application context relocation process. The coordination of the application context relocation process that may be performed by the source EES is exemplified as follows.

[0140] ● The source EES may identify that the UE has moved to the target EES service area and modify (coordinate) the application context relocation process as follows.

[0141] ■ The source EES may not send an application context relocation completion to the UE (for example, the source EES may modify the context relocation process so as not to send a response message to the EEC for a context relocation request previously received from the EEC). In cases where communication between the source EES and the UE is not possible through such coordination, overhead can be reduced by preventing duplicate signal transmissions.

[0142] In step 5, the target EES may send an application context relocation completion to the EEC. Since communication between the source EES and the UE is not possible, the target EES (instead of the source EES) sends the application context relocation completion to notify the UE of the application context relocation completion.

[0143] The operations of steps 4 and 5 above are summarized as follows.

[0144] ● The source EES may recognize the fact that the UE has moved to the service area of the target EES and modify the application context relocation process as follows.

[0145] ■ The source EES may not send an application context relocation completion to the UE (for example, the source EES may modify the process so as not to send a response message to the EEC for a context relocation request previously received from the EEC). In cases where communication between the source EES and the UE is not possible through such coordination, overhead can be reduced by preventing the transmission of duplicate signaling.

[0146] ■ The target EES rather than the source EES may send the application context relocation completion to the EEC. Therefore, the target EES may perform an application function impact on the service routing to reroute the application data service instead of the UE. This will be described in detail below.

[0147] In step 6, the EEC may receive the application context relocation completion from the target EES instead of the source EES and perform rerouting for the application data service. The UE may recognize that it will receive the application context relocation completion from the target EES via the EEC registration process performed by moving to the service area of the target EES. In the case where the target EES performs rerouting for the application data service, the UE does not perform this operation (the operation of performing rerouting for the application data service).

[0148] Figure 5 is a message flow diagram showing the operation of the source EES according to an embodiment of the present disclosure.

[0149] Reference Figure 5 , the source EES may determine the relocation mode. In addition, the source EES may send the determined relocation mode to the EEC and the EAS. Since the specific method for determining the relocation mode is the same as the above method, it will be omitted below.

[0150] The process of determining the relocation mode may be omitted. In the case where the determination of the relocation mode is omitted (i.e., in the case where the relocation mode is not determined), if the application context relocation process is initiated, the source EES may send a relocation in progress indication to all devices. Alternatively, the relocation mode may be determined by each device, and in this case, the process for sending the relocation mode may also be omitted.

[0151] Thereafter, the source EES may identify whether the application context relocation process is initiated. In addition, the source EES may determine the device that initiates the application context relocation process.

[0152] In the case where the relocation mode is determined, the source EES may determine the device to which the relocation in progress indication is sent based on the determined mode.

[0153] 1. Specifically, the case where the device that initiates the application context relocation process is the source EES will be described.

[0154] In this case, the source EES may send a relocation in progress indication to the determined device. For example, the source EES may send an indication to the EAS and the EEC that do not initiate the application context relocation process.

[0155] The source EES may identify whether an EEC registration notification has been received from the target EES. In the case of receiving the notification, the source EES may perform the EEC deregistration process after completing the application context relocation. In addition, the source EES may not perform an AF impact on the service routing.

[0156] In the case of not receiving a notification, the source EES may perform an AF impact on the service routing after completing the application context relocation. The source EES may perform an EEC deregistration process.

[0157] 2. The case where the device initiating the application context relocation process is the EEC will be described.

[0158] In this case, the source EES may send an in - progress relocation indication to the source EAS. According to the indication, the source EAS may not initiate the application context relocation process.

[0159] The source EES may identify whether it has received an EEC registration notification from the source EES. In the case of receiving the notification, the source EES may coordinate the application context relocation process. That is, the source EES may identify the fact that the UE has moved to the target EES and modify the process so as not to send an application context relocation completion to the UE. Through this coordination, duplicate signaling transmissions can be prevented.

[0160] In the case of not receiving the notification, the source EES may send the result of the application context relocation to the EEC.

[0161] Figure 6 It is a message flow diagram showing the operations of the target EES according to an embodiment of the present disclosure.

[0162] Reference Figure 6 , the target EES may identify whether the EEC registration process has been performed.

[0163] In the case of having performed the EEC registration process, the target EES may send an EEC registration notification to the source EES.

[0164] The target EES may identify the device initiating the application context relocation process. In the case where the device is the EEC, the target EES may send an application context relocation completion notification message to the EEC after completing the application context relocation. In the case where the UE cannot communicate with the source EES according to the movement of the UE, the target EES instead of the source EES may send an application context relocation completion notification message to the UE, thereby preventing duplicate signaling transmissions.

[0165] In the case where the device initiating the application context relocation process is the source EES or the source EAS, the target EES may perform an AF request to impact the service routing after the application context relocation process is completed.

[0166] In addition to the deployment scenarios of the above - mentioned embodiments, embodiments of the case of ensuring communication between the UE and the source EES outside the service area of the source EES are as follows.

[0167] ● In the case where the source EES initiates the application context relocation process, the source EES may send an in-relocation indication to all source EASs that provide services to the UE's EEC and the UE. The source EES may select the device to which the in-relocation indication is sent according to the relocation mode pre-determined by the source EES before sending the in-relocation indication. Therefore, there is no need to send an indication (in-relocation indication) to a device that will not perform the application context relocation process according to the conditions of the mode. Since the detailed description of the relocation mode is the same as that described above, its description will be omitted below.

[0168] In addition, the in-relocation indication sent to the EEC may include information capable of identifying which application context relocation client of the UE is in progress. The in-relocation indication sent to the source EAS may include information capable of identifying the UE or the EEC in the UE (e.g., EEC ID, UE ID, UE IP address, or an ID assigned from the authentication and authorization function). However, the identifier may not be included in the in-relocation indication.

[0169] ● In the case where the source EAS that provides services to the UE initiates the application context relocation process, the source EES may send an in-relocation indication to another source EAS that provides services to the UE's EEC and the UE. The in-relocation indication sent to the EEC may include information capable of identifying which application context relocation client of the UE is in progress.

[0170] The in-relocation indication sent to the source EAS may include information capable of identifying the UE or the EEC (e.g., EEC ID, UE ID, UE IP address, or an ID assigned from the authentication and authorization function, etc.).

[0171] ● In the case where the UE initiates the application context relocation process and the source EES receives a context relocation request from the UE, the source EES may send an in-relocation indication to the source EAS that provides services to the UE.

[0172] Figure 7 is a message flow diagram showing operations that can be performed for coordination in the application context relocation process according to the present disclosure.

[0173] Figure 7 An embodiment of the specific operations of the application context relocation process based on the source EES (the process in which a device in the source edge data network initiates the application context relocation process) according to the above embodiment is shown.

[0174] In step 0, the source EES may determine the relocation mode and send the relocation mode to the EEC and the source EAS. Its detailed description is the same as that described above and will be omitted below. In addition, according to an embodiment, step 0 may be omitted.

[0175] In step 1, an application context relocation process can be initiated. The application context relocation process can be initiated (or triggered) in the EEC, the source EAS, and the source EES respectively.

[0176] In the case where the application context relocation process is initiated or triggered in the EEC or the source EAS, the source EES can receive a context relocation request from the EEC (step 2A), or can receive a context relocation request from the source EAS (step 2B). In addition, the source EES can directly perform the operation of initiating the application context relocation process. Thus, in the case where the source EES receives a context relocation request, or in the case where the source EES directly initiates the application context relocation process, the source EES can send a relocation in progress indication to another device. In this case, the source EES can determine the device (EEC or source EAS) to which the relocation in progress indication is sent based on the determined relocation mode. Alternatively, in the case where the relocation mode is not determined, the source EES can send an indication to all devices.

[0177] The source EES can obtain the target EES information in step 3 and send an application context relocation request to the target EES in step 4.

[0178] After receiving the application context relocation request from the source EES (after step 4), when performing the EEC registration process, the target EES can send an EEC registration notification to the source EES. The notification can include information capable of identifying the UE or the EEC in the UE.

[0179] Once the EEC registration notification is received, the source EES can modify the ongoing application context relocation process. Specifically, the source EES can identify that communication with the EEC is no longer possible, and can refrain from performing the sending of application context relocation completion and the AF impact on service routing.

[0180] The operations of the source EES can be performed by the target EES, or some operations (application data service rerouting) can be performed by the EEC in the UE.

[0181] Specifically, in step 12B, the target EES can send an application context relocation completion (or response) to the UE. In the case where the source EES does not receive an EEC registration notification from the target EES, in step 12A, the source EES can send an application context relocation completion (or response) to the EEC.

[0182] In addition, in step 13B or 13C, the source EES or the target EES can trigger an AF request to affect service routing. Its detailed description is the same as that described above and will be omitted below.

[0183] Figure 8 It is a message flow diagram showing operations that can be performed for coordination during an application context relocation process according to the present disclosure.

[0184] Figure 8 An embodiment showing the detailed operations of the above-described embodiment of the application context relocation process based on the target EES (a process initiated by the EEC, application client, or MT in the UE and sending an application context relocation request to the target EES).

[0185] In step 1, the EEC can determine whether to initiate an application context relocation process, and in the case of determining to initiate the application context relocation process, in step 2, the EEC can send an application context relocation request to the target EES. In this case, the application context relocation request can include at least one of UE information (e.g., UE ID or IP address), S-EAS information, application information, or the EEC registration context ID. In addition, the application context request can also include information about the relocation mode. However, this information can be omitted.

[0186] After the target EES receives the application context relocation request from the EEC (after step 2), the target EES can send an in-relocation indication to the source EES to which the corresponding UE is connected.

[0187] As described above, the EEC can provide the target EES with information about the relocation mode received from the source EES, and the target EES can use this information (information about the relocation mode) to determine the device to which the in-relocation indication is sent (e.g., the target EES can use this information to determine whether to send an indication to the source EES). For example, according to the corresponding mode, in the case where only the UE can initiate the application context relocation process, the target EES may not send an in-relocation indication to the source EES.

[0188] The in-relocation indication can include information capable of identifying the UE or the EEC in the corresponding UE (e.g., EEC ID, UE ID, UE IP address, or ID assigned from the authentication and authorization function, etc.). The source EES can send the corresponding in-relocation indication to the source EAS that provides services to the UE.

[0189] As another embodiment, the in-relocation indication can be included in Figure 8 the application context relocation request in steps 5 and 6 to be sent to the source EES and the source EAS. As in the above-described embodiment, it can be determined whether to include and send the corresponding indication according to the information about the relocation mode provided by the EEC.

[0190] Figure 9is a block diagram showing the structure of a server according to the present disclosure.

[0191] Referring Figure 9 , the server may include a transceiver 910, a controller 920, and a storage unit 930. In the present disclosure, the controller may be defined as a circuit, an application specific integrated circuit, or at least one processor.

[0192] In this case, the server may correspond to at least one of an EES, an EAS, or an edge data network configuration server.

[0193] The transceiver 910 may send signals to other network entities and receive signals from other network entities. The transceiver 910 may send information to and receive information from, for example, another server through a specific interface.

[0194] According to an embodiment proposed in the present disclosure, the controller 920 may control the overall operation of the server. For example, the controller 920 may control the signal flow between blocks in order to perform the operations according to the above flowchart.

[0195] The storage unit 930 may store at least one of the information sent and received through the transceiver 910 or the information generated through the controller 920.

[0196] Figure 10 is a block diagram showing the structure of a UE according to the present disclosure.

[0197] Referring Figure 10 , the UE may include a transceiver 1010, a controller 1020, and a storage unit 1030. In the present disclosure, the controller may be defined as a circuit, an application specific integrated circuit, or at least one processor.

[0198] The transceiver 1010 may send signals to other network entities and receive signals from other network entities.

[0199] According to an embodiment proposed in the present disclosure, the controller 1020 may control the overall operation of the server. For example, the controller 1020 may control the signal flow between blocks in order to perform the operations according to the above flowchart.

[0200] The storage unit 1030 may store at least one of the information sent and received through the transceiver 1010 or the information generated through the controller 1020.

[0201] The present disclosure proposes a method for performing coordination during an application context relocation process that can be initiated from multiple devices, thereby enabling selection of an optimal device to initiate the application context relocation process and reducing signaling overhead.

[0202] For the above purposes, the present disclosure provides a coordinated method for performing an application context relocation process among a UE (or an EEC in the UE), an EAS, and an EEC.

[0203] In addition, the present disclosure proposes a method for notifying each of an EAS and a UE (or an EEC in the UE) of the ability to initiate an application context relocation process to the EAS (application context relocation initiation ability).

[0204] In addition, the present disclosure proposes a method for notifying another device (e.g., an EEC, an EES, an EAS, etc.) of information on the progress of an application context relocation process initiated in one device.

[0205] The above-mentioned edge computing system can obtain the information required to provide edge computing services to a UE through a 3GPP system. For this purpose, an EES subscribes to a network exposure function (NEF) which is one of the 3GPP network functions (NFs), and the NEF subscribes to receive information about the target UE from other 3GPP NFs, so as to receive information about the UE from the 3GPP system. In the case where the UE moves, there may be an overhead of repeating subscription / cancellation of subscription in the 3GPP system in order to obtain information. Hereinafter, to solve the overhead problem, a method for minimizing the repetition of subscription / cancellation configuration between the 3GPP NF that exposes UE-related information to an edge computing device (e.g., an EES) and the 3GPP NF that provides UE-related information will be described.

[0206] Figure 11 It is a flowchart showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0207] When performing the registration process to the EEC of the UE, if source EES-related information is provided from the UE, the target EES may determine that it is necessary to transmit UE service API context information.

[0208] The source EES information (or source server information) provided by the UE through the EEC registration process may include only the identifier of the source server (source EES) or the address information of the source server (source EES). In addition, the source server information may include the identifier of the source server and the address information of the source server, and include at least one of various information required for data transmission and reception between the source server and the UE (e.g., source EAS information (identifier and address information) that has provided services to the application client in the UE, the application client identifier and related information that has received edge computing services, and UE service API information required to provide edge computing services to the application client).

[0209] If only the identifier is provided, the target EES shall receive the address information of the source EES from the edge data network configuration server.

[0210] Accordingly, the target EES can determine the characteristics of the application provided to the UE. Specifically, the target EES can identify whether the UE is using a stateful application service. In this case, a stateful application service may refer to an application service that requires continuous operation state information of the client and the server to provide a seamless service, and includes, for example, the above-mentioned real-time interactive game application. That is, the target EES can identify whether the application context relocation process is executed (or whether it is necessary). This can be determined based on whether the target EES has received an application context relocation request from the source server. However, the embodiments of the present disclosure are not limited thereto, and specific examples will be described later.

[0211] In the case where the UE is using a stateless application service, an independent process of various embodiments of the UE service API context transfer method to be described later can be executed. Figure 12 of the UE service API context transfer method to be described later can be executed.

[0212] Since the UE is receiving a stateful application service, in the case where the application context relocation process needs to be executed, the application context relocation process can be applied as one of various embodiments of the UE service API context transfer method. Detailed descriptions of various embodiments will be described later.

[0213] Specific examples of the UE determining the characteristics of the received application service (stateful or stateless) are as follows.

[0214] - The UE (EEC) can determine the application service characteristics based on the EAS service profile information providing the requested service, or

[0215] - The UE can determine the application service characteristics based on the provided source EAS information, or

[0216] - The UE can determine the application service characteristics according to whether an application context relocation request is received.

[0217] However, the embodiments of the present disclosure are not limited thereto, and various methods for determining the characteristics of the application service can be used.

[0218] The scope of the present disclosure is not limited to the above embodiments. That is, when the conditions for performing the operations according to each embodiment are satisfied without a process of determining the applied characteristics, the target server may perform the corresponding operations. For example, after performing the registration process of the UE, the target server may perform the processes corresponding to various embodiments of the present disclosure. As another example, in the case of performing the application context relocation process, the target server may perform the processes corresponding to various embodiments of the present disclosure.

[0219] Figure 12 is a message flow diagram showing a method of transmitting a UE service API context according to an embodiment of the present disclosure.

[0220] Reference Figure 12 , the EEC of the UE may perform an EEC registration process (step 0) with the target EES to which the UE has moved. When performing the registration process, the UE may provide at least one of the source EES ID or address information (e.g., fully qualified domain name (FQDN), IP address, etc.) of the source EES. This is to enable the target EES to identify the source EES and send a UE service API context request.

[0221] The target EES may perform an operation of looking up the address of the source EES based on the information received from the EEC of the UE. For example, the target EES may query the edge data network configuration server to receive the address of the source EES. Alternatively, information about the address of the source EES may be stored in the target EES, and the target EES may look up the address of the source EES based on the information received from the UE.

[0222] The target EES may send a UE service API context request to the identified source EES (step 1).

[0223] The UE service API context request may include at least one of the following information.

[0224] - The EEC ID of the UE that has performed the registration process on itself: This identifier may be an identifier provided by the authentication and authorization function when the UE performs authentication / authorization, or an ID (EEC registration context ID) given by the source EES during the EEC registration process. In addition, at least one of the identifiers that can identify the UE other than the EEC ID (e.g., identifier information such as a generic public subscription identifier (GPSI)) or the UE IP address may be sent together, or at least one of the identifier or UE IP address that can identify the UE instead of the EEC ID may be sent.

[0225] - Target EES information: It may include at least one of a target EES FQDN, a target EES IP address, a target EES ID, or edge computing service provider information (e.g., ECSPID).

[0226] - EAS information (application ID, EAS ID, EAS category, etc.) that the target EES has provided services to the UE.

[0227] The source EES can identify UE-related information provided by the EAS that has already provided services to the UE and the 3GPP system based on the information received from the target EES. The source EES can send information about the 3GPP NF (e.g., NEF or SCEF) that has exposed UE-related information based on the identified information to the target EES. The source EES can send a response message (UE service API context response) including relevant UE service API context information to the target EES (step 2).

[0228] UE service API context information may include at least one of information such as NEF ID / address, subscription-related ID, or notification-related ID.

[0229] The subscription-related ID is an identifier for subscription information between a consumer NF and a provider NF (e.g., information about which UE, what information is provided, the subscription between what devices, and information about the NF related to the provided information). The subscription-related ID can be used to specify the subscription to be modified. An event provider NF (e.g., NEF) can provide the subscription-related ID to a consumer NF (e.g., EES or EAS).

[0230] The subscription-related ID is needed to find the NEF that should perform the subscription using the NEF ID / address and identify the subscription performed between the NEF and the source EES for the UE. After identifying the NEF and modifying the target subscription, the target EES can modify the subscription between the NEF and the source EES by performing a subscription operation on the target NEF.

[0231] The target EES can perform the following operations based on the UE service API context information received from the source EES (step 3).

[0232] - Case 1: If the NEF subscribed by the source EES is a NEF that the target EES can subscribe to (determined based on the NEF ID / address received from the source EES)

[0233] ◆ Subscribe to the target NEF based on at least one of the subscription ID, notification target address (target EES information), or notification-related ID received from the source EES.

[0234] ◆ The NEF identifies subscription-related information of the existing source EES based on the subscription-related ID included in the subscription request message of the target EES. The NEF can change the notification target address from the source EES address to the target EES address. That is, the NEF can maintain the southbound interface-related configuration between the NEF and NFs (such as Access and Mobility Management Function (AMF), Session Management Function (SMF), and Policy Control Function (PCF)) in the 3GPP system, and change the northbound API configuration exposed to the higher application layer (such as EES as an application function in the 3GPP system). The northbound API refers to the interface exposed by the NEF to the application functions (such as EES, EAS) in the upper layer (application layer). The southbound interface refers to the lower layer (lower than the application layer) interface between the NEF and NFs (such as AMF, SMF, PCF, etc.) in the 3GPP system.

[0235] - Case 2: If the NEF subscribed by the source EES is a NEF that the target EES cannot subscribe to (determined based on the NEF ID / address received from the source EES)

[0236] ◆ The target EES performs a new subscription to the NEF it subscribes to and links to.

[0237] ● The target EES can provide UE identification information to the NEF to specify the UE. The UE identification information can be GPSI, external ID, UE IP address, etc.

[0238] The target EES can send a subscription result (subscription indication) to the source EES according to Step 3 (Step 4). Once the subscription is successful (Step 3, Case 1), the source EES can delete the UE service API context-related information stored locally and perform deregistration on the UE (EEC). In addition, the source EES can not perform an unsubscribe request to the NEF (Step 5).

[0239] Once the subscription fails (Step 3, Case 2), the source EES can perform an unsubscribe request to the NEF.

[0240] The detailed operations of Step 5 are as follows.

[0241] Case 1: The target EES successfully subscribes to the NEF

[0242] ◆ Delete the UE service API context information stored in the source EES.

[0243] ◆ Perform the EEC deregistration process.

[0244] ◆ Do not perform an unsubscribe operation on the NEF.

[0245] Case 2: The target EES fails to subscribe to the NEF sent by the source EES.

[0246] ◆ The source EES performs an unsubscribe operation to the NEF for the corresponding UE.

[0247] Figure 13 It is a message flow diagram showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0248] Refer to Figure 13 , the EEC of the UE can perform an EEC registration process to the target EES that the UE has moved to (step 0). When performing the registration process, the UE can provide at least one of the source EES ID or address information (e.g., FQDN, IP address, etc.) of the source EES. This is to enable the target EES to identify the source EES and send a UE service API context request.

[0249] The target EES can perform an operation to find the address of the source EES based on the information received from the EEC of the UE. For example, the target EES can query the source EES address received from the edge data network configuration server. Alternatively, information about the address of the source EES can be stored in the target EES, and the address of the source EES can be found based on the information received from the UE.

[0250] The target EES can send a UE service API context request to the identified source EES (step 1).

[0251] The UE service API context request can include at least one of the following information.

[0252] - The EEC ID of the UE that has performed the registration process on itself: This identifier can be an identifier provided by the authentication and authorization function when the UE performs authentication / authorization, or an ID given by the source EES during the EEC registration process (EEC registration context ID). In addition, at least one of the identifiers that can identify the UE other than the EEC ID (e.g., identifier information such as a general public subscription identifier (GPSI)) or the UE IP address can be sent together, or the UE IP address or at least one of the identifiers that can identify the UE instead of the EEC ID can be sent.

[0253] - Target EES information: It can include at least one of the target EES FQDN, target EES IP address, target EES ID, or edge computing service provider information (e.g., ECSPID). In this case, the target EES address information that can be used as the notification target address of the NEF in the 3GPP system can be included.

[0254] - EAS information (application ID, EAS ID, EAS category, etc.) that the target EES has provided services to the UE.

[0255] - NEF information subscribed by the target EES or NEF information that the target EES can use (NEF ID / address)

[0256] After that, the source EES can identify whether the NEF that the target EES can use is the NEF it subscribed for the corresponding UE based on the information received from the target EES (step 2).

[0257] - In the case where the NEF is the NEF subscribed and already used by the source EES, the source EES can identify the UE-related information provided by the EAS and the 3GPP system that has already provided services to the UE, and look up the relevant subscription-related ID. The source EES can modify the subscription of the 3GPP NF (e.g., NEF or SCEF) that has already exposed the information related to the corresponding UE based on the identified information. In addition, the source EES can modify the notification target address to the target EES address and store the relevant notification-related ID.

[0258] - If the NEF is not the NEF subscribed and already used by the source EES, the source EES sends a modification failure message to the target EES through the following step 3.

[0259] The source EES can send a response message (UE service API context response) including the UE service API context information to the target EES (step 3). The UE service API context information can include information about the modified subscription. The response message can include an indication that can represent the subscription modification result.

[0260] The UE service API context information can include at least one of information such as NEF ID / address, subscription-related ID, notification-related ID, notification target address, or event ID. The subscription-related ID is necessary to support management operations such as modification and deletion of the corresponding subscription, and the event provider NF (e.g., NEF) can be provided to the consumer NF (e.g., EES or EAS).

[0261] The target EES can perform the following operations based on the UE service API context information and the subscription modification result received from the source EES.

[0262] Case 1: Successful subscription modification (when the NEF subscribed by the source EES is the NEF that the target EES can subscribe)

[0263] ◆ Store the UE service API context information received from the source EES (e.g., at least one of subscription ID, notification target address (target EES information), or notification-related ID).

[0264] Case 2: Subscription modification failure (when the NEF subscribed by the source EES is the NEF that the target EES cannot subscribe)

[0265] ◆ The target EES performs a new subscription to the NEF it subscribes to and links to.

[0266] ● The target EES may provide UE identification information to the NEF to specify the UE. The UE identification information may be GPSI, external ID, UE IP address, etc.

[0267] Figure 14 It is a message flow diagram showing a method for transmitting a UE service API context according to various embodiments of the present disclosure.

[0268] Figure 14 It shows an application context relocation process based on the source EES.

[0269] To support a UE using a stateful application service through the corresponding process, the source EES sends the application context information stored in the source EAS that provides services to the UE to the target EAS.

[0270] In the above process, the source EES may send an application context relocation request to the target EES. The present disclosure proposes a method for performing UE service context API transmission without performing a separate process by sending UE service API context information together when sending an application context relocation request. Figures 11 to 13 The specific method is as follows. Figure 14 The process can be executed according to the above Figure 11 process, or can be executed when performing a process for supporting a UE using a stateful application service.

[0271] Since the detailed description of steps 1 to 3 is the same as the above description, it will be omitted here.

[0272] By adding at least one of the following information to the application context relocation request, the source EES can send the application context relocation request.

[0273] ◆ At least one of NEF ID / address, subscription-related ID (a reference ID that can specify the source EES's subscription to the NEF for the target UE), EEC ID, or EEC registration context ID

[0274] Thereafter, the target EES may send an application context relocation request to the target EAS in step 5 and receive an application context relocation response in step 6.

[0275] The target EES may subscribe to the NEF in operation A (subscribe to the NEF)

[0276] ◆ If the NEF indicated by the source EES is a NEF that the target EES can subscribe to, the target EES can modify the subscription between the NEF and the source EES by performing a subscription using the subscription - related ID.

[0277] ◆ If the NEF indicated by the source EES is a NEF that the target EES cannot subscribe to, the target EES performs a new subscription operation for the target UE to the NEF subscribed by the target EES. The target EES can provide at least one of the GPSI, external ID, or UE IP address to the NEF to specify the target UE.

[0278] In step 7, the target EES can send an application context relocation response to the source EES. The subscription result of the NEF (the result of operation A: whether the target EES can subscribe to the NEF connected to the source EES) can be included in the application context relocation response.

[0279] Accordingly, in operation B, the source EES can perform the following operations according to the subscription indication of the target EES.

[0280] ◆ Case 1: The target EES successfully subscribes to the NEF indicated by the source EES.

[0281] ● Delete the UE service API context information stored in the source EES.

[0282] ● Perform an EEC deregistration process.

[0283] ● Do not perform an unsubscribe operation on the NEF.

[0284] ◆ Case 2: The target EES fails to subscribe to the NEF indicated by the source EES.

[0285] ● The source EES performs an unsubscribe operation to the NEF for the corresponding UE.

[0286] Figure 15 It is a message flow diagram showing a method for transmitting a UE service API context according to an embodiment of the present disclosure.

[0287] Steps 1 to 4 are processes in which the target EES receives an application context relocation request from the UE's EEC and accordingly sends and receives an application context relocation request to and from the target EAS, and their detailed descriptions will be omitted.

[0288] In step 5, the target EES may send an application context relocation request to the source EES. In this case, the target EES may include and send a UE service API context request in the application context relocation request. The target EES may search for the address of the source EES based on the information received from the UE's EEC to send the request message. Alternatively, the target EES may query the edge data network configuration server to receive the address of the source EES. The UE service API context request may include at least one of the following information.

[0289] ● Information capable of identifying the UE or EEC for which the registration process has been performed on itself

[0290] - EEC ID: The corresponding identifier may be the identifier provided by the authentication and authorization function when the UE performs authentication / authorization, or the ID given during the EEC registration process in the source EES (EEC registration context ID).

[0291] - At least one of the information such as the GPSI, external ID, or UE IP address that can identify the UE may be sent together, or at least one of the UE IP address or the identifier that can identify the UE instead of the EEC ID may be sent.

[0292] ● Target EES information: At least one of the target EES FQDN, target EES IP address, target EES ID, or edge computing service provider information (e.g., ECSPID).

[0293] ● EAS information (application ID, EAS ID, EAS category, etc.) that the target EES has provided services to the UE

[0294] Thereafter, the source EES may send an application context relocation request to the source EAS in step 6 and receive an application context relocation response in step 7.

[0295] In step 8, the source EES may send an application context relocation response to the target EES. In this case, the source EES may include and send UE service API context information in the application context relocation response.

[0296] The source EES may identify UE-related information provided by the EAS that has provided services to the UE and the 3GPP system based on the information received from the target EES. The source EES may transmit information about the 3GPP NF (e.g., NEF or SCEF) that has exposed information related to the corresponding UE based on the identified information. The source EES may send a response message including the relevant UE service API context information to the target EES.

[0297] UE service API context information may include at least one of information such as NEF ID / address, subscription-related ID, or notification-related ID.

[0298] The target EES may subscribe to the NEF (subscribe to the NEF service) in operation A. In this case, the target EES may operate based on the UE service API context information received in step 8. The specific operations are as follows.

[0299] Case 1: If the NEF subscribed by the source EES is a NEF that the target EES can subscribe to (determined based on the NEF ID / address received by the source EES)

[0300] ◆ Subscribe to the NEF that includes at least one of the subscription ID received by the source EES or the notification target address (target EES information). In addition, the notification-related ID may be included.

[0301] ◆ The NEF may identify the subscription-related information of the existing source EES based on the subscription-related ID in the subscription request of the target EES. The NEF may change the notification target address from the source EES address to the target EES address. That is, the NEF may maintain the southbound configuration (interface) and change the northbound API configuration (interface).

[0302] Case 2: If the NEF subscribed by the source EES is a NEF that the target EES cannot subscribe to (determined based on the NEF ID / address received by the source EES)

[0303] ◆ The target EES performs a new subscription to the NEF it subscribes to and links to.

[0304] ● The target EES may provide UE identification information to the NEF to specify the UE. The UE identification information may be GPSI, external ID, UE IP address, etc.

[0305] The target EES may send the result of operation A in step 9 to the source EES.

[0306] When the subscription to the NEF notified to the source EES is successful (Case 1), the target EES deletes the UE service API context-related information stored locally and performs the UE (EEC) deregistration process. In addition, the source EES does not send an unsubscribe request to the NEF.

[0307] When the subscription to the NEF notified to the source EES fails (Case 2), the source EES sends an unsubscribe request for the UE related to the NEF.

[0308] Its detailed description can be summarized as operation B below.

[0309] In operation B, the source EES may perform the following operation scenarios based on the subscription indication of the target EES: Scenario 1: The target EES successfully subscribes to the NEF indicated by the source EES.

[0310] ◆ Delete the UE service API context information stored in the source EES.

[0311] ◆ Perform an EEC deregistration process.

[0312] ◆ Do not perform an unsubscribe operation on the NEF.

[0313] Scenario 2: The target EES fails to subscribe to the NEF sent by the source EES.

[0314] ◆ The source EES performs an unsubscribe operation to the NEF for the corresponding UE.

[0315] Figure 16 It is a message flow diagram showing a method for transmitting UE service API context according to an embodiment of the present disclosure.

[0316] Reference Figure 16 , in step 0, when performing the EEC registration process to the target EES, the EEC in the UE may provide the source EES ID and address information (e.g., FQDN, IP address, etc.) of the source EES. This enables the target EES to identify the source EES to send a UE service API context request.

[0317] The target EES may perform an operation to find the address of the source EES based on the information received from the EEC in the UE (the target EES may obtain the address of the source EES by querying the edge data network configuration server). Thereafter, in step 1, the target EES may send a UE service API context request to the source EES. The UE service API context request may include the following information.

[0318] ● The EEC ID of the UE that has performed the registration process on itself: This identifier may be the identifier provided by the authentication and authorization function when the UE performs authentication / authorization, or the ID given by the source EES during the EEC registration process (EEC registration context ID).

[0319] - In addition to the EEC ID, identifier information such as GPSI or UE IP address that can identify the UE may be sent.

[0320] ● Target EES information: It may include target EES FQDN, target EES IP address, target EES ID, edge computing service provider information (e.g., ECSPID), etc. The target EES information may include the target EES address information, which may be used as the notification target address of the NEF in the 3GPP system.

[0321] ● Provide EAS information (application ID, EAS ID, EAS category, etc.) of the EAS that serves the UE connected to the target EES

[0322] ● Service API-related information provided by the target EES for the UE to the EAS

[0323] ● NEF information subscribed by the target EES or NEF information that the target EES can use (NEF ID / address)

[0324] In step 2, the source EES can identify whether the NEF that the target EES can use, based on the information received from the target EES, is the NEF that it has already subscribed for the corresponding UE.

[0325] ● In the case where the NEF is the NEF subscribed and already used by the source EES, the source EES can identify the UE-related information received from the target UE, the EAS that has already served the corresponding UE, and the 3GPP system, and look up (identify) the relevant subscription-related ID. The source EES can modify the subscription of the 3GPP NF (e.g., NEF or SCEF) that has already exposed the information related to the corresponding UE based on the identified information. The source EES can change the notification target address to the target EES address and store the relevant notification-related ID.

[0326] ● If the NEF is not the NEF subscribed and already used by the source EES, the source EES sends a modification failure message to the target EES through the following step 3.

[0327] In step 3, the source EES can include the UE service API context information related to the subscription modification performed by itself in the response message (UE service API context response) and send the response message to the target EES. The response message can include an indication that can represent the subscription modification result. The information transmitted through the response message can be NEF ID / address, subscription-related ID, notification-related ID, notification target address, event ID, etc. The subscription-related ID is the information required to support management operations such as modification and deletion of the corresponding subscription. In addition to the subscription-related ID, the response message can include information for specifying the service-related transaction of the subscription and is transmitted (e.g., transaction reference ID, AF transaction ID, etc.). Regardless of whether the subscription modification is successful, the list of capability exposure services (the list of services provided by the source EES to the source EAS for the corresponding UE) and the information (address and ID) about the NEF linked to provide the exposure service can be provided to the target EES together.

[0328] In step 4, the target EES can perform the following operations based on the subscription modification result and the UE service API context information received from the source EES.

[0329] - Case 1: Subscription modification is successful (if the NEF subscribed by the source EES is a NEF that the target EES can subscribe to)

[0330] ◆ Store the UE service API context information received from the source EES (store the subscription ID, notification target address (target EES information), and notification correlation ID).

[0331] - Case 2: Subscription modification fails (if the NEF subscribed by the source EES is a NEF that the target EES cannot subscribe to)

[0332] ◆ The target EES performs a new subscription to the NEF to which it is subscribed and linked.

[0333] ● The target EES can provide UE identification information to the NEF to specify the UE. In this case, the UE identification information can be GPSI, external ID, UE IP address, etc.

[0334] Figure 17 is a block diagram showing a method in which a source EES subscribes to a NEF to obtain UE information according to an embodiment of the present disclosure.

[0335] Reference Figure 17 , when the source EES of the present disclosure subscribes to an event exposure service for a UE, the source EES can identify the EES that can be connected to it as the notification target and subscribe to the event exposure service on behalf of the EES.

[0336] That is, the source EES can subscribe to the 3GPP event exposure service from the NEF on behalf of the adjacent EES and EAS, map the IDs of the events corresponding to each of the EES and EAS and the notification target addresses, and store them as context information.

[0337] Thereafter, in the case where the UE moves to the service area of the target EES, the source EES can identify whether the target EES exists in the list of EESs for which a pre-subscription is to be performed instead. In the case where the target EES is an EES that has been previously subscribed to in the source EES, the source EES can identify the notification target address and notification correlation ID corresponding to the target EES.

[0338] The source EES can configure the notification target address of future-occurring events as the target EES address based on the identified notification target address and notification correlation ID.

[0339] Reference Figure 17 The described embodiments can be applied to the above embodiments, and the source EES of the present disclosure can know the events to be modified, the notification target address, the subscription correlation ID, etc. through the method described in Figure 17 .

[0340] Figure 18 is a block diagram showing the structure of a server according to an embodiment of the present disclosure.

[0341] Referring to Figure 18 , the server may include a transceiver 1810, a controller 1820, and a storage unit 1830. In the present disclosure, the controller may be defined as a circuit, an application specific integrated circuit, or at least one processor.

[0342] In this case, the server may correspond to at least one of an EES, an EAS, or an edge data network configuration server.

[0343] The transceiver 1810 may send signals to other network entities and receive signals from other network entities. The transceiver 1810 may send information to and receive information from, for example, another server through a specific interface.

[0344] According to an embodiment proposed in the present disclosure, the controller 1820 may control the overall operation of the server. For example, the controller 1820 may control the signal flow between blocks to perform the operations according to the above flowchart.

[0345] The storage unit 1830 may store at least one of the information sent and received through the transceiver 1810 or the information generated through the controller 1820.

[0346] Figure 19 is a block diagram showing the structure of a UE according to an embodiment of the present disclosure.

[0347] Referring to Figure 19 , the UE may include a transceiver 1910, a controller 1920, and a storage unit 1930. In the present disclosure, the controller may be defined as a circuit, an application specific integrated circuit, or at least one processor.

[0348] The transceiver 1910 may send signals to other network entities and receive signals from other network entities.

[0349] According to an embodiment proposed in the present disclosure, the controller 1920 may control the overall operation of the UE. For example, the controller 1920 may control the signal flow between blocks to perform the operations according to the above flowchart.

[0350] The storage unit 1930 may store at least one of the information sent and received through the transceiver 1910 or the information generated through the controller 1920.

[0351] The above embodiments are prepared by focusing on operations that interact with the NEF, which is a network exposure function of the 3GPP 5G system. However, network functions that expose UE service APIs to provide UE-related information in the 3GPP system are not limited to the NEF. That is, in the above operations, a device that executes a network function (such as a PCF or an SMF) can directly perform exposure to an edge computing system. In an edge computing service provisioning scenario through the 3GPP 4G system, the SCEF can be an application target of the present disclosure.

[0352] In addition, the device that directly receives exposure information in edge computing is not limited to the EES. The EAS or an edge data network configuration server can also directly obtain and use UE-related information exposed through the 3GPP system. That is, the operation subject of the present disclosure can be the EAS and the edge data network configuration server in addition to the EES, and these can be collectively referred to as servers. Therefore, the exchange of UE service API context information can be performed not only between EESs, but also between various devices (for example, the present disclosure can be applied to exchanges between EES <-> EAS and edge data network configuration server <-> EES, exchanges between EESs, exchanges between EASs, or exchanges between edge data network configuration servers).

[0353] The information that can be obtained through the UE service API mentioned in the present disclosure can include all UE-related information that can be provided by the 3GPP system. For example, information about the NF serving the UE and at least one of information such as the communication service quality (QoS) provided to the UE, the policy applied to the UE, and the location and UE identifier of the UE used in the 3GPP system can be provided to the edge computing service through the UE service API.

[0354] In the present disclosure, the UE service API context information is not limited to information related to the NF subscribed by the existing source EES. The UE service API context information can include all information required to find the 3GPP system network function that can provide the information required for edge computing services (for example, at least one of information for NEF discovery such as an S-NSSAI, event IDs supported by the application function, external identifiers, external group identifiers, or domain names). In addition, the UE service API is not limited to a specific single UE, and includes an API for obtaining information about a group composed of specific UEs. Considering this, the UE service API context information can also include information about the group composed of UEs. In this case, the information about the UE group included in the UE service API context can include a group ID.

[0355] The present disclosure provides a method for obtaining information about a UE using edge computing services in a 3GPP system (e.g., providing a UE service API). Specifically, the present disclosure proposes a method for obtaining information about a UE in the case where the UE using edge computing services moves (i.e., a method that supports mobility in the method for obtaining information about a UE).

[0356] In addition, the present disclosure proposes a method for sending and receiving UE service API context information for obtaining UE-related information provided from a 3GPP system between EESs.

[0357] In addition, the present disclosure proposes a method for an EES or an EAS to modify a subscription to a 3GPP network function based on the provided UE service API context information. This involves subscribing to the northbound API of the 3GPP network function.

[0358] In addition, the present disclosure proposes a method for maintaining a subscription made by a 3GPP network function (such as a NEF) that provides a northbound API for edge computing services to other 3GPP network functions regardless of the mobility of the UE. The corresponding subscription is a subscription between 3GPP network functions and is established to provide the above UE service API.

[0359] In the drawings used to describe the method of the present disclosure, the described order does not necessarily correspond to the execution order, and the precedence relationship may change or may be executed in parallel.

[0360] Alternatively, within the scope not impairing the essence of the present disclosure, some components may be omitted, and only some components may be included in the drawings showing the method of the present disclosure.

[0361] In addition, within the scope not impairing the essence of the present disclosure, the method of the present disclosure may be implemented in a combination including some or all of the contents included in each embodiment.

[0362] In addition, the information included in the messages in the present disclosure is used to describe examples of the present disclosure, and some information may be omitted or additional information may be included.

[0363] In the detailed description of the present disclosure, specific embodiments have been described, but various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments and should be defined not only by the following claims but also by equivalents of these claims.

Claims

1. A method performed by a source Edge Enablement Server (EES) for application context relocation in a wireless communication system, the method comprises: receiving, from a target EES, a User Equipment (UE) service Application Programming Interface (API) context request comprising an Edge Enablement Client (EEC) context ID and information about a subscription; updating a subscription to a Network Exposure Function (NEF) based on the information about the subscription; and sending a UE service API context response to the target EES.

2. The method according to claim 1, wherein the UE service API context request further comprises at least one of a target EES ID, an Edge Application Server (EAS) ID, or an EEC ID.

3. The method according to claim 1, wherein the information about the subscription comprises a subscription-related ID or a notification target address.

4. The method according to claim 3, wherein updating the subscription to the NEF is performed based on the subscription-related ID.

5. A method performed by a target Edge Enablement Server (EES) for application context relocation in a wireless communication system, the method comprises: sending, to a source EES, a User Equipment (UE) service Application Programming Interface (API) context request comprising an Edge Enablement Client (EEC) context ID and information about a subscription; and receiving, from the source EES, a UE service API context response, wherein updating a subscription to a Network Exposure Function (NEF) is performed by the source EES based on the information about the subscription.

6. The method according to claim 5, wherein the UE service API context request further comprises at least one of a target EES ID, an Edge Application Server (EAS) ID, or an EEC ID.

7. The method according to claim 5, wherein the information about the subscription comprises a subscription-related ID or a notification target address.

8. The method according to claim 7, wherein updating the subscription to the NEF is performed based on the subscription-related ID.

9. A source Edge Enablement Server (EES) for application context relocation in a wireless communication system, the source EES comprises: a transceiver; and a controller coupled to the transceiver and configured to: receive, from a target EES, a User Equipment (UE) service Application Programming Interface (API) context request comprising an Edge Enablement Client (EEC) context ID and information about a subscription, update a subscription to a Network Exposure Function (NEF) based on the information about the subscription, and send a UE service API context response to the target EES.

10. The source EES according to claim 9, wherein the UE service API context request further comprises at least one of a target EES ID, an Edge Application Server (EAS) ID, or an EEC ID.

11. The source EES according to claim 9, wherein the information about the subscription comprises a subscription-related ID or a notification target address.

12. The source EES according to claim 11, wherein updating the subscription to the NEF is performed based on the subscription-related ID.

13. A target Edge Enablement Server (EES) for applying context relocation in a wireless communication system, the target EES comprises: a transceiver; and a controller, coupled to the transceiver and configured to: send a User Equipment (UE) service Application Programming Interface (API) context request including an Edge Enablement Client (EEC) context ID and information about a subscription to a source EES, and receive a UE service API context response from the source EES, wherein an update of the subscription to the Network Exposure Function (NEF) is performed by the source EES based on the information about the subscription.

14. The target EES according to claim 13, wherein the UE service API context request further includes at least one of a target EES ID, an Edge Application Server (EAS) ID, or an EEC ID.

15. The target EES according to claim 13, wherein the information about the subscription includes a subscription-related ID or a notification target address.

16. The target EES according to claim 15, wherein the update of the subscription to the NEF is performed based on the subscription-related ID.

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