A session migration method and device, electronic equipment and storage medium
By introducing an emergency SMF mechanism to obtain user information and establish UPF relationships, seamless migration of VoLTE services is achieved, resolving call drop issues caused by SMF failures and ensuring that user experience is not affected.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA MOBILE GROUP SICHUAN
- Filing Date
- 2022-07-13
- Publication Date
- 2026-08-04
AI Technical Summary
In 5G networks, when the Session Management Function (SMF) fails, existing technologies cause users who are using VoLTE services to experience dropped calls, affecting user experience.
By introducing an emergency SMF when an SMF fails, a request is sent to the User Plane Function (UPF) to obtain user information, and a corresponding relationship is established based on the information. Then, a session request is sent to the relevant UPF to achieve session migration, ensuring the continuity of VoLTE services.
In the event of an SMF failure, seamless migration of VoLTE services was achieved, ensuring that the user experience was not affected.
Smart Images
Figure CN117440447B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of communication technology, and specifically relates to a session migration method, apparatus, electronic device and storage medium. Background Technology
[0002] In 5G networks, the control plane / user plane (C / U) is separated. The session management function (SMF) of the control plane and the user plane function (UPF) of the user plane communicate via message communication through the control and user plane separation of EPC nodes (CUPS) protocol on the N4 interface.
[0003] When the SMF fails, it releases all services it carries. The SMF then notifies the Authentication Management Function (AMF), which in turn notifies the terminal to initiate the deregistration process. For data services in use, the terminal re-reports registration and service requests after going offline, and the network quickly notifies the service to go offline. When the data service comes back online, it selects a new SMF, avoiding the failed SMF, and the service experience is not noticeable. However, for Voice over Long-Term Evolution (VoLTE) services that are in a call, when the SMF notifies the deletion of the session, it will directly cause a dropped call, which is noticeable to the customer and affects the user experience. Summary of the Invention
[0004] This application provides a session migration method, apparatus, electronic device, and storage medium that can achieve session migration in the event of an SMF failure, while ensuring that the service experience of users currently using VoLTE services is not affected.
[0005] In a first aspect, embodiments of this application provide a session migration method, comprising: in the event of a failure of a first session management function (SMF), an emergency SMF sends a first request to a first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, the first request is used to obtain first information of a first user, the first user including at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, the first information including user identification information and network service information; establishing a correspondence between the first UPF and the first user based on the first information; when the network service information indicates that the first user is a second user and a target session request is received from the first user, the emergency SMF sends a second request to a second UPF, wherein the second UPF includes at least one of a plurality of first UPFs associated with the first user, the second request is used to obtain target session information related to the first user, the second user including a user who has activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service; and responding to the target session request based on the target session information.
[0006] Secondly, embodiments of this application provide a session migration method, executed by a network storage function (NRF), comprising: receiving a fault reporting message sent by a first session management function (SMF), wherein the fault reporting message includes a first cause indicating a fault in the first SMF and service information carried by the first SMF; and activating an emergency SMF when the first cause indicates a temporary fault in the first SMF, wherein the emergency SMF is used to send a first request to a first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, and the first request is used to obtain first information of a first user, wherein the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, and the plurality of services carried by the first SMF... The corresponding multiple UEs are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is also used to establish a correspondence between the first UPF and the first user based on the first information. The emergency SMF is also used to send a second request to the second UPF when the network service information indicates that the first user is a second user and a target session request of the first user is received. The second UPF includes at least one of a plurality of first UPFs that correspond to the first user. The second request is used to obtain target session information related to the first user. The second user includes users who have activated the Long Term Evolution Voice Bearer (VoLTE) service. The emergency SMF is also used to respond to the target session request based on the target session information.
[0007] Thirdly, embodiments of this application provide a session migration method executed by a User Plane Function (UPF). The UPF includes at least one of a plurality of UPFs associated with a first SMF, where the first SMF is at least one of a plurality of SMFs that have failed. The method includes: sending a first response message and / or a second response message to an emergency SMF. The first response message carries first information of a first user, where the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF. The first information includes user identification information and network service information. The network service information is used to indicate whether the first user has activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service. The second response message carries target session information related to the first user, whereby the target session information is used by the emergency SMF to respond to the first user's target session request.
[0008] Fourthly, embodiments of this application provide a session migration apparatus, comprising: a first request module, configured to, in the event of a failure of a first session management function (SMF), send a first request from an emergency SMF to a first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, and the first request is used to obtain first information of a first user, wherein the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, and the first information includes user identification information and network service information; an establishment module, configured to, based on the first information, establish a correspondence between the first UPF and the first user; a second request module, configured to, when the network service information indicates that the first user is a second user and a target session request is received from the first user, send a second request from the emergency SMF to a second UPF, wherein the second UPF includes at least one of a plurality of first UPFs associated with the first user, and the second request is used to obtain target session information related to the first user, wherein the second user includes a user who has activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service; and a response module, configured to, based on the target session information, have the emergency SMF respond to the target session request.
[0009] Fifthly, this application provides a session migration apparatus applied to a network storage function (NRF), comprising: a receiving module for receiving a fault reporting message sent by a first session management function (SMF), wherein the fault reporting message includes a first cause indicating a fault in the first SMF and service information carried by the first SMF; and a control module for activating an emergency SMF when the first cause indicates a temporary fault in the first SMF, wherein the emergency SMF is used to send a first request to a first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, and the first request is used to obtain first information of a first user, wherein the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF. The multiple UEs corresponding to the multiple services carried are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is also used to establish a correspondence between the first UPF and the first user based on the first information. The emergency SMF is also used to send a second request to the second UPF when the network service information indicates that the first user is a second user and a target session request of the first user is received. The second UPF includes at least one of a plurality of first UPFs that correspond to the first user. The second request is used to obtain target session information related to the first user. The second user includes users who have activated the Long Term Evolution Voice Bearer (VoLTE) service. The emergency SMF is also used to respond to the target session request based on the target session information.
[0010] In a sixth aspect, embodiments of this application provide a session migration apparatus applied to a User Plane Function (UPF), wherein the UPF includes at least one of a plurality of UPFs associated with a first SMF, the first SMF being at least one of a plurality of SMFs that have failed, comprising: a sending module, configured to send a first response message and / or a second response message to an emergency SMF, wherein the first response message carries first information of a first user, the first user including at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, the first information including user identification information and network service information, the network service information being used to indicate whether the first user has activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service, and the second response message carrying target session information related to the first user, the target session information being used by the emergency SMF to respond to the target session request of the first user.
[0011] In a seventh aspect, embodiments of this application provide an electronic device including a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps of the session migration method as described in the first, second, or third aspect.
[0012] Eighthly, embodiments of this application provide a readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of the session migration method as described in the first, second, or third aspect.
[0013] Ninthly, embodiments of this application provide a chip, the chip including a processor and a communication interface, the communication interface being coupled to the processor, the processor being used to run programs or instructions to implement the session migration method as described in the first, second, or third aspect.
[0014] In this embodiment, when the first session management function (SMF) fails, the emergency SMF sends a first request to the first user plane function (UPF). The first UPF includes at least one of multiple UPFs associated with the first SMF. The first request is used to obtain first information about a first user, which includes at least one of multiple user terminals (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information. Based on the first information, a correspondence is established between the first UPF and the first user. When the network service information indicates that the first user is a second user and a target session request from the first user is received, the emergency SMF sends a second request to a second UPF. The second UPF includes at least one of multiple first UPFs associated with the first user. The second request is used to obtain target session information related to the first user, which includes users who have activated VoLTE (Voice over LTE) services. Based on the target session information, the emergency SMF responds to the target session request, enabling session migration in the event of an SMF failure while ensuring that the service experience of users currently using VoLTE services is not affected. Attached Figure Description
[0015] Figure 1 This is a flowchart illustrating a session migration method provided in an embodiment of this application;
[0016] Figure 2 This is a flowchart illustrating another session migration method provided in an embodiment of this application;
[0017] Figure 3This is a flowchart illustrating another session migration method provided in an embodiment of this application;
[0018] Figure 4 This is a flowchart illustrating another session migration method provided in an embodiment of this application;
[0019] Figure 5 This is a schematic diagram of the structure of a session migration device provided in an embodiment of this application;
[0020] Figure 6 This is a schematic diagram of another session migration device provided in an embodiment of this application;
[0021] Figure 7 This is a schematic diagram of the structure of another session migration device provided in the embodiments of this application;
[0022] Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation
[0023] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0024] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.
[0025] The following description, in conjunction with the accompanying drawings, details a session migration method, apparatus, electronic device, and storage medium provided in this application through specific embodiments and application scenarios.
[0026] 5G networks implement C / U separation and C / D separation, and the User Plane Filter (UPF) supports various Session and Service Continuity (SSC) modes to ensure high bandwidth, low latency, and large connection requirements in different service application scenarios. However, the analysis of 5G network faults mainly focuses on user plane UPF fault scenarios, such as using multiple UPFs for load balancing to provide hot or cold standby services; for link faults between the campus UPF and 5GC, a kite-like solution is proposed for temporary mitigation. However, for control plane network (SMF) fault scenarios, the current common practice is to promptly take the services carried by the faulty network element offline, forcing the service to interrupt and then re-initiate the request to avoid the faulty network element. In this scenario, for common data services, the brief service interruption is not noticeable, depending only on the speed of network-side service removal. However, for VoLTE services, this will result in voice service interruption, and regardless of the speed of removal, the customer's service experience will be affected. Therefore, a solution is urgently needed to ensure that customers using VoLTE services are not affected when the SMF fails.
[0027] Figure 1 This application illustrates a session migration method provided by an embodiment of the present application, which can be executed by an electronic device. In other words, the method can be executed by software or hardware installed on the electronic device, and includes the following steps:
[0028] S101: In the event of a failure of the first session management function (SMF), the emergency SMF sends a first request to the first user plane function (UPF).
[0029] The first UPF includes at least one of a plurality of UPFs associated with the first SMF, the first request is used to obtain first information of the first user, the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, and the first information includes user identification information and network service information.
[0030] In this embodiment, an emergency SMF is sought through the 5GC network NRF to replace the faulty SMF, and the session data is synchronized by the UPF in reverse notification to the emergency SMF.
[0031] Specifically, this embodiment can establish an N+1 emergency disaster recovery mechanism in the 5GC network by dividing it into SMF POOLs. N represents the number of normally operating SMFs, and 1 represents an emergency SMF whose hardware resource configuration and software parameter configuration are the same as other SMFs in the POOL, but which has not been configured with network infrastructure data (such as interface IP, NF capability, and other software parameter data). Under normal circumstances, the emergency SMF is unavailable. When a normally operating SMF fails, the NRF notifies the emergency SMF to copy the network infrastructure data of the failed SMF. The emergency SMF inherits the NF instantiation data of the failed SMF, sets the failed SMF to be unavailable, and sets the emergency SMF to be suspended. Only user requests with established sessions are sent to the emergency SMF for processing.
[0032] Meanwhile, through the N4_BASICDATA_GETREQUEST / N4_BASICDATA_GETRESPONSE process between N4 interfaces, the emergency SMF proactively synchronizes session data with the UPF connected to the faulty SMF to obtain the current user's session data, including: basic data such as user IMSI / GUTI, and currently online 5QI bearer information.
[0033] S102: Based on the first information, establish the correspondence between the first UPF and the first user.
[0034] In this step, the emergency SMF can record the correspondence between the current business user and the corresponding UPF, so as to facilitate the subsequent acquisition of the current business user's session information.
[0035] S103: When the network service information indicates that the first user is the second user and the target session request of the first user is received, the emergency SMF sends a second request to the second UPF.
[0036] The second UPF includes at least one of a plurality of first UPFs that correspond to the first user, and the second request is used to obtain target session information related to the first user. The second user includes users who have activated the Long Term Evolution Voice Bearer (VoLTE) service.
[0037] S104: Based on the target session information, the emergency SMF responds to the target session request.
[0038] The emergency SMF first determines the VoLTE user based on the basic data obtained from the UPF: if a session with 5QI=1 or 1&2 has not been established, the user is a non-VoLTE user; if a session with 5QI=1 or 1&2 has been established, the user is a VoLTE user.
[0039] For VoLTE users, the terminal initiates various signaling procedures. For example, after the UE initiates a PDU session modification, the AMF receives the message and sends Nsmf_PDUSession_UpdateSMContext to the emergency SMF to update the terminal session context. The N4_SESSIONDATA_GETREQUEST / N4_BASICDATA_GETRESPONSE procedure between the N4 interfaces is also involved. Based on the user-UPF correspondence obtained by the emergency SMF in the aforementioned steps, the AMF notifies the UPF to obtain session data, N4 session context, and other information from the UPF, completing session-level data continuity. The emergency SMF synchronizes the session data and N4 session context information from the UPF. The emergency SMF responds to the terminal's PDU session update request according to the existing procedure, replying with Nsmf_PDUSession_UpdateSMContextResponse to continue the terminal's signaling procedures and process the terminal-initiated signaling procedures normally, thereby achieving session reconstruction on the N4 interface and ensuring uninterrupted VoLTE service.
[0040] This application provides a session migration method that uses an emergency SMF to screen and identify VoLTE users. For VoLTE user session information, session data is synchronized to the emergency SMF via a UPF to ensure normal service continuity for VoLTE users and unimpeded service experience.
[0041] This application provides a session migration method. When a first Session Management Function (SMF) fails, an emergency SMF sends a first request to a first User Plane Function (UPF). The first UPF includes at least one of multiple UPFs associated with the first SMF. The first request is used to obtain first information about a first user, which includes at least one of multiple User Terminal Equipment (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information. Based on the first information, a correspondence is established between the first UPF and the first user. When the network service information indicates that the first user is a second user and a target session request from the first user is received, the emergency SMF sends a second request to a second UPF. The second UPF includes at least one of multiple first UPFs associated with the first user. The second request is used to obtain target session information related to the first user, which includes users who have activated VoLTE (Voice over LTE) services. Based on the target session information, the emergency SMF responds to the target session request, enabling session migration in the event of an SMF failure while ensuring that the service experience of users currently using VoLTE services is not affected.
[0042] In one implementation, after step S101 above, the method further includes:
[0043] Based on the network configuration data of the first SMF, the emergency SMF configures its own network, wherein the network configuration data is sent by the Network Storage Function (NRF).
[0044] Specifically, the NRF notifies the emergency SMF of the IP address, slicing support information, and other capabilities of the faulty SMF. The emergency SMF then replicates its own network equipment data based on this information to ensure that subsequent signaling sent to the faulty SMF will be carried by the emergency SMF.
[0045] In one implementation, after step S104 above, the method further includes:
[0046] The emergency SMF sends a first message to the authentication management function AMF, wherein the first message is used to notify the AMF to release session resources associated with the first user.
[0047] When a VoLTE session ends, the UPF notifies the emergency SMF to update the 5QI data, and the emergency SMF notifies the AMF to deregister users. This process continues until the number of users on the emergency SMF reaches 0. Then, the NRF is notified to modify the emergency SMF's status, changing it to unavailable and ceasing to process any signaling.
[0048] In one implementation, after step S101 above, the method further includes:
[0049] When the network service information indicates that the first user is a third user, the emergency SMF sends a second message to the authentication management function AMF, wherein the second message is used to notify the AMF to release session resources related to the first user, and the third user includes users who have not activated VoLTE service.
[0050] For terminals without VoLTE service, the existing procedures can be followed to notify the terminals to go offline and re-register with the network, which can reduce the burden on the emergency SMF.
[0051] As can be seen from the above embodiments, in order to achieve session migration in the event of an SMF failure, while ensuring that the service experience of users currently using VoLTE services is not affected, communication and cooperation between various network elements in the network are required. For example, when a normally operating SMF fails, the NRF notifies the emergency SMF to perform configuration replication according to the network equipment data of the failed SMF. The emergency SMF inherits the NF instantiation data of the failed SMF, sets the failed SMF to unavailable, sets the emergency SMF to suspended, and sends user requests for established sessions to the emergency SMF for processing.
[0052] Therefore, another embodiment of this application provides a session migration method, performed by the Network Storage Function (NRF), such as... Figure 2 As shown, the method includes the following steps:
[0053] S201: Receive the fault reporting message sent by the first session management function (SMF).
[0054] The fault reporting message includes a first reason for the fault in the first SMF and the service information carried by the first SMF.
[0055] For example, the faulty SMF can be reported to the NRF by the faulty SMF itself or by the maintenance personnel. The SMF service deregistration process is then performed on the NRF, and the cause value and the amount of traffic it carries are reported. For example, REASON CODE = 111 indicates that the SMF is temporarily faulty.
[0056] S202: If the first cause indicates that the first SMF has a temporary failure, activate the emergency SMF.
[0057] The emergency SMF is configured to send a first request to a first User Plane Function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF. The first request is configured to obtain first information of a first user, wherein the first user includes at least one of a plurality of User Terminal Equipment (UEs) corresponding to a plurality of services carried by the first SMF. The plurality of UEs corresponding to the plurality of services carried by the first SMF are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is further configured to establish a correspondence between the first UPF and the first user based on the first information. The emergency SMF is further configured to send a second request to a second UPF when the network service information indicates that the first user is a second user and a target session request is received from the first user. The second UPF includes at least one of a plurality of first UPFs associated with the first user. The second request is configured to obtain target session information related to the first user, wherein the second user includes a user who has activated the Long Term Evolution (LTE) Voice Bearer (VoLTE) service. The emergency SMF is further configured to respond to the target session request based on the target session information.
[0058] For example, the NRF modifies the state of the faulty SMF, establishes an emergency SMF, and modifies the state of the emergency SMF: After receiving a request from the SMF with the deregistration reason value REASON CODE=111, the NRF changes the state of the faulty SMF to unavailable and changes the state of the emergency SMF from unavailable to suspended. Subsequently, the emergency SMF executes the various steps of the session migration method in the aforementioned embodiment, which will not be repeated here.
[0059] In one implementation, after step S202 above, the method further includes:
[0060] A third message is sent to the emergency SMF, wherein the third message carries network configuration data of the first SMF, and the network configuration data is used by the emergency SMF to configure its own network.
[0061] For example, the NRF will notify the emergency SMF of the IP address, slicing support information and other capabilities of the faulty SMF. The emergency SMF will then copy its own network equipment data based on the faulty SMF, and the subsequent signaling sent to the faulty SMF will be carried by the emergency SMF.
[0062] This application provides a session migration method executed by a Network Storage Function (NRF). It receives a fault reporting message from a First Session Management Function (SMF), wherein the fault reporting message includes a first cause indicating a fault in the first SMF and service information carried by the first SMF. If the first cause indicates a temporary fault in the first SMF, an emergency SMF is activated. The emergency SMF sends a first request to a First User Plane Function (UPF), wherein the first UPF includes at least one of multiple UPFs associated with the first SMF. The first request is used to obtain first information about a first user, which includes at least one of multiple User Terminal Equipment (UEs) corresponding to multiple services carried by the first SMF. The multiple UEs corresponding to the multiple services carried by the first SMF are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is also used to establish a correspondence between the first UPF and the first user based on the first information. The emergency SMF is also used to send a second request to the second UPF when the network service information indicates that the first user is a second user and a target session request from the first user is received. The second UPF includes at least one of a plurality of first UPFs that correspond to the first user. The second request is used to obtain target session information related to the first user. The second user includes users who have activated the Long Term Evolution Voice Bearer (VoLTE) service. The emergency SMF is also used to respond to the target session request based on the target session information, enabling session migration in the event of an SMF failure, while ensuring that the service experience of users currently using VoLTE services is not affected.
[0063] Another embodiment of this application provides a session migration method executed by a User Plane Function (UPF), wherein the UPF includes at least one of a plurality of UPFs associated with a first SMF, and the first SMF is at least one of a plurality of SMFs that have failed, such as... Figure 3 As shown, the method includes the following steps:
[0064] S301: Send a first response message and / or a second response message to the emergency SMF.
[0065] The first response message carries first information of a first user, which includes at least one of multiple user terminals (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information. The network service information is used to indicate whether the first user has activated the Long Term Evolution Voice Bearer (VoLTE) service. The second response message carries target session information related to the first user. The target session information is used by the emergency SMF to respond to the target session request of the first user.
[0066] The UPF interacts with the SMF via the N4 interface and is directly controlled and managed by the SMF. It executes service flow processing according to various policies published by the SMF. The aforementioned emergency SMF sends a first request to the first UPF, where the first UPF includes at least one of multiple UPFs associated with the first SMF. The first request is used to obtain first information about a first user, where the first user includes at least one of multiple user terminals (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information. The first UPF sends a first response message to the emergency SMF, carrying the first information. The aforementioned emergency SMF then sends a second request to a second UPF, where the second UPF includes at least one of multiple first UPFs corresponding to the first user. The second request is used to obtain target session information related to the first user, where the second user includes users who have activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service. The second UPF sends a second response message to the emergency SMF, carrying the target session information.
[0067] This application provides a session migration method executed by a User Plane Function (UPF). The UPF includes at least one of multiple UPFs associated with a first Service Provider Function (SMF), where the first SMF is at least one of multiple SMFs that have failed. The method involves sending a first response message and / or a second response message to an emergency SMF. The first response message carries first information about a first user, which includes at least one of multiple User Terminals (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information. The network service information is used to indicate whether the first user has activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service. The second response message carries target session information related to the first user. This target session information is used by the emergency SMF to respond to the first user's target session request. This method enables session migration in the event of an SMF failure while ensuring that the service experience of users currently using VoLTE services is not affected.
[0068] Figure 4A schematic flowchart illustrating a session migration method provided in an embodiment of this application, such as... Figure 4 As shown, the method includes the following steps:
[0069] S401: Notify NRF of an SMF failure.
[0070] That is, the first SMF sends a fault reporting message to the NRF, wherein the fault reporting message includes a first reason for the fault of the first SMF and the service information carried by the first SMF.
[0071] S402: NRF performs faulty SMF status modification and establishes an emergency SMF.
[0072] In the event that the first cause indicates a temporary failure of the first SMF, an emergency SMF is activated. The emergency SMF sends a first request to a first User Plane Function (UPF), where the first UPF includes at least one of multiple UPFs associated with the first SMF. The first request is used to obtain first information about a first user, where the first user includes at least one of multiple User Terminal Equipment (UEs) corresponding to multiple services carried by the first SMF. The multiple UEs corresponding to the multiple services carried by the first SMF are determined based on service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is also used to establish a correspondence between the first UPF and the first user based on the first information. Furthermore, when the network service information indicates that the first user is a second user and a target session request from the first user is received, the emergency SMF sends a second request to a second UPF, where the second UPF includes at least one of multiple first UPFs associated with the first user. The second request is used to obtain target session information related to the first user, where the second user includes a user who has activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service. The emergency SMF is also used to respond to the target session request based on the target session information.
[0073] S403: Obtain basic data, VoLTE user judgment.
[0074] In the event of a failure of the first session management function (SMF), the emergency SMF sends a first request to the first user plane function (UPF). The first UPF includes at least one of a plurality of UPFs associated with the first SMF. The first request is used to obtain first information of the first user. The first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF. The first information includes user identification information and network service information.
[0075] S404: Notify non-VoLTE user terminals to register.
[0076] That is, after the emergency SMF sends the first request to the first user plane function UPF, if the network service information indicates that the first user is a third user, the emergency SMF sends a second message to the authentication management function AMF. The second message is used to notify the AMF to release the session resources associated with the first user. The third user includes users who have not activated VoLTE service.
[0077] S405: VoLTE user reports PDU session modification request.
[0078] In this step, the VoLTE user terminal transmits the PDU session modification request through the 5G base station.
[0079] S406: Request to update session data.
[0080] After receiving the above request, the AMF sends Nsmf_PDUSession_UpdateSMContext to the emergency SMF to update the terminal session context.
[0081] S407: Get session data.
[0082] When the network service information indicates that the first user is the second user and a target session request is received from the first user, the emergency SMF sends a second request to the second UPF, wherein the second UPF includes at least one of a plurality of first UPFs that correspond to the first user, and the second request is used to obtain target session information related to the first user, wherein the second user includes a user who has activated the Long Term Evolution Voice Bearer (VoLTE) service.
[0083] In this step, the N4_SESSIONDATA_GETREQUEST / N4_BASICDATA_GETRESPONSE process between N4 interfaces, based on the user-UPF correspondence obtained by the aforementioned emergency SMF, the SMF notifies the UPF to obtain session data, N4 session context and other information from the UPF, and completes session-level data connection.
[0084] S408: Response session update.
[0085] In this step, the emergency SMF responds to the terminal's PDU session update request according to the existing procedure, replying with Nsmf_PDUSession_UpdateSMContext Response to ensure uninterrupted VoLTE service.
[0086] This application provides a session migration method that seeks an emergency SMF to replace the faulty SMF through the 5GC network NRF, and uses the UPF to notify the emergency SMF to synchronize session data. For terminals without VoLTE service, the existing process is followed to notify the terminal to go offline and re-register to the network, reducing the burden on the new SMF. For terminals with VoLTE service, VoLTE session is restored to achieve session migration, while ensuring that the service experience of users currently using VoLTE service is not affected.
[0087] It should be noted that the session migration method provided in this application embodiment can be executed by a session migration device or a control module within that session migration device for executing the session migration method. This application embodiment uses the execution of the session migration method by a session migration device as an example to illustrate the session migration device provided in this application embodiment.
[0088] Figure 5 This diagram illustrates the structure of a session migration apparatus according to an embodiment of this application. Figure 5 As shown, the session migration device 500 includes: a first request module 510, configured to, in the event of a failure of the first session management function (SMF), send a first request from the emergency SMF to the first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, and the first request is used to obtain first information of a first user, wherein the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, and the first information includes user identification information and network service information; an establishment module 520, configured to, based on the first information, establish a correspondence between the first UPF and the first user; a second request module 530, configured to, when the network service information indicates that the first user is a second user and a target session request of the first user is received, send a second request from the emergency SMF to the second UPF, wherein the second UPF includes at least one of a plurality of first UPFs associated with the first user, and the second request is used to obtain target session information related to the first user, wherein the second user includes a user who has activated the Long Term Evolution (LTE) Voice over LTE (VoLTE) service; and a response module 540, configured to, based on the target session information, have the emergency SMF respond to the target session request.
[0089] This application provides a session migration apparatus, which includes a first request module for sending a first request from an emergency SMF to a first User Plane Function (UPF) when a first Session Management Function (SMF) fails. The first UPF includes at least one of multiple UPFs associated with the first SMF. The first request is used to obtain first information about a first user, including at least one of multiple User Terminal Equipment (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information. A second request module is used to establish a correspondence between the first UPF and the first user based on the first information. A second request module is used for sending a second request from the emergency SMF to a second UPF when the network service information indicates that the first user is a second user and a target session request from the first user is received. The second UPF includes at least one of multiple first UPFs associated with the first user. The second request is used to obtain target session information related to the first user, including users who have activated VoLTE (Voice over LTE) services. A response module is used for responding to the target session request based on the target session information. This allows for session migration in the event of an SMF failure while ensuring that the service experience of users currently using VoLTE services is not affected.
[0090] In one implementation, the first request module 510 is further configured to: configure its own network according to the network configuration data of the first SMF, wherein the network configuration data is sent by the Network Storage Function (NRF).
[0091] In one implementation, the response module 540 is further configured to: send a first message to the authentication management function AMF, wherein the first message is used to notify the AMF to release session resources associated with the first user.
[0092] In one implementation, the first request module 510 is further configured to: when the network service information indicates that the first user is a third user, the emergency SMF sends a second message to the authentication management function AMF, wherein the second message is used to notify the AMF to release session resources related to the first user, and the third user includes users who have not activated VoLTE service.
[0093] Figure 6 This diagram illustrates the structure of another session migration apparatus provided in one embodiment of this application. Figure 6As shown, the session migration device 600, applied to the network storage function (NRF), includes: a receiving module 610, configured to receive a fault reporting message sent by a first session management function (SMF), wherein the fault reporting message includes a first cause indicating a fault in the first SMF and service information carried by the first SMF; and a control module 620, configured to activate an emergency SMF when the first cause indicates a temporary fault in the first SMF, wherein the emergency SMF is configured to send a first request to a first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, and the first request is configured to obtain first information of a first user, wherein the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF. The multiple UEs corresponding to multiple services are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is also used to establish a correspondence between the first UPF and the first user based on the first information. The emergency SMF is also used to send a second request to the second UPF when the network service information indicates that the first user is a second user and a target session request of the first user is received. The second UPF includes at least one of a plurality of first UPFs that correspond to the first user. The second request is used to obtain target session information related to the first user. The second user includes users who have activated the Long Term Evolution Voice Bearer (VoLTE) service. The emergency SMF is also used to respond to the target session request based on the target session information.
[0094] In one implementation, the control module 620 is further configured to:
[0095] A third message is sent to the emergency SMF, wherein the third message carries network configuration data of the first SMF, and the network configuration data is used by the emergency SMF to configure its own network.
[0096] Figure 7 This diagram illustrates the structure of yet another session migration apparatus provided in one embodiment of this application. Figure 7As shown, a session migration device 700 is applied to a User Plane Function (UPF). The UPF includes at least one of a plurality of UPFs associated with a first SMF, where the first SMF is at least one of a plurality of SMFs that have failed. The device includes a sending module 710, configured to send a first response message and / or a second response message to an emergency SMF. The first response message carries first information of a first user, where the first user includes at least one of a plurality of User Terminals (UEs) corresponding to a plurality of services carried by the first SMF. The first information includes user identification information and network service information, whereby the network service information is used to indicate whether the first user has activated the Long Term Evolution (LTE) Voice Bearer (VoLTE) service. The second response message carries target session information related to the first user, whereby the target session information is used by the emergency SMF to respond to the target session request of the first user.
[0097] The session migration device in this application embodiment can be a device, or a component, integrated circuit, or chip in a terminal. The device can be a mobile electronic device or a non-mobile electronic device. For example, mobile electronic devices can be mobile phones, tablets, laptops, PDAs, in-vehicle electronic devices, wearable devices, ultra-mobile personal computers (UMPCs), netbooks, or personal digital assistants (PDAs), etc., while non-mobile electronic devices can be servers, network-attached storage (NAS), personal computers (PCs), televisions (TVs), ATMs, or self-service machines, etc. This application embodiment does not impose specific limitations.
[0098] The session migration device in this application embodiment can be a device with an operating system. The operating system can be Android, iOS, or other possible operating systems; this application embodiment does not specifically limit the specific operating system used.
[0099] The session migration device provided in this application embodiment can achieve... Figures 1 to 4 To avoid repetition, the various processes implemented in the method embodiments will not be described again here.
[0100] Optional, such as Figure 8As shown, this application embodiment also provides an electronic device 800, including a processor 801, a memory 802, and a program or instructions stored in the memory 802 and executable on the processor 801. When the program or instructions are executed by the processor 801, the following is implemented: In the event of a failure of the first session management function (SMF), the emergency SMF sends a first request to the first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, the first request is used to obtain first information of a first user, the first user including at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, and the first information includes user identification information and network service information; based on the first information, an association is established between the first UPF and... The first user's correspondence; when the network service information indicates that the first user is the second user and a target session request from the first user is received, the emergency SMF sends a second request to the second UPF, wherein the second UPF includes at least one of a plurality of first UPFs that correspond to the first user, and the second request is used to obtain target session information related to the first user, wherein the second user includes users who have activated the Long Term Evolution Voice Bearer (VoLTE) service; according to the target session information, the emergency SMF responds to the target session request; or receives a fault reporting message sent by the first session management function SMF, wherein the fault reporting message includes a first cause indicating that the first SMF has failed and the service information carried by the first SMF;In the event that the first cause indicates a temporary failure of the first SMF, an emergency SMF is activated. The emergency SMF is used to send a first request to a first User Plane Function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF. The first request is used to obtain first information of a first user, wherein the first user includes at least one of a plurality of User Terminal Equipment (UEs) corresponding to a plurality of services carried by the first SMF. The plurality of UEs corresponding to the plurality of services carried by the first SMF are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is also used to establish a correspondence between the first UPF and the first user based on the first information. Furthermore, if the network service information indicates that the first user is a second user and a target session request from the first user is received, the emergency SMF is used to send a second request to a second UPF. In this context, the second UPF includes at least one of a plurality of first UPFs corresponding to the first user. The second request is used to obtain target session information related to the first user. The second user includes a user who has activated the Long Term Evolution (LTE) Voice Bearer (VoLTE) service. The emergency SMF is further used to respond to the target session request based on the target session information; or to send a first response message and / or a second response message to the emergency SMF. The first response message carries first information of the first user, which includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF. The first information includes user identification information and network service information. The network service information is used to indicate whether the first user has activated the LTE Voice Bearer (VoLTE) service. The second response message carries target session information related to the first user, which is used by the emergency SMF to respond to the target session request of the first user.
[0101] In one implementation, when the above program or instructions are executed by the processor 801, the emergency SMF configures its own network according to the network configuration data of the first SMF, wherein the network configuration data is sent by the network storage function NRF.
[0102] In one implementation, when the above program or instruction is executed by the processor 801, the emergency SMF sends a first message to the authentication management function AMF, wherein the first message is used to notify the AMF to release session resources associated with the first user.
[0103] In one implementation, when the above program or instruction is executed by the processor 801, the following is implemented: when the network service information indicates that the first user is a third user, the emergency SMF sends a second message to the authentication management function AMF, wherein the second message is used to notify the AMF to release session resources related to the first user, and the third user includes users who have not activated VoLTE service.
[0104] In one implementation, when the above program or instruction is executed by the processor 801, it performs the following: sending a third message to the emergency SMF, wherein the third message carries network configuration data of the first SMF, and the network configuration data is used by the emergency SMF to configure its own network.
[0105] The specific execution steps described above can be found in the various steps of the above-described session migration method embodiment, and can achieve the same technical effect. To avoid repetition, they will not be repeated here.
[0106] It should be noted that the electronic devices in the embodiments of this application include: servers, terminal devices, or other devices besides terminal devices.
[0107] The above electronic device structure does not constitute a limitation on the electronic device. An electronic device may include more or fewer components than illustrated, or combine certain components, or arrange them differently. For example, an input unit may include a Graphics Processing Unit (GPU) and a microphone, and a display unit may use a liquid crystal display (LCD), organic light-emitting diode (OLED), or other similar display panels. User input units include at least one of a touch panel and other input devices. A touch panel is also called a touchscreen. Other input devices may include, but are not limited to, physical keyboards, function keys (such as volume control buttons, power buttons, etc.), trackballs, mice, and joysticks, which will not be elaborated further here.
[0108] Memory can be used to store software programs and various data. Memory can primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area can store the operating system, application programs or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, memory can include volatile memory or non-volatile memory, or both. Non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SynchlinkDRAM, SLDRAM), and direct memory bus RAM (DRRAM).
[0109] The processor may include one or more processing units; optionally, the processor integrates an application processor and a modem processor, wherein the application processor mainly handles operations related to the operating system, user interface, and applications, while the modem processor mainly handles wireless communication signals, such as a baseband processor. It is understood that the aforementioned modem processor may also not be integrated into the processor.
[0110] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the various processes of the above-described session migration method embodiments and achieve the same technical effect. To avoid repetition, they will not be described again here.
[0111] The processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.
[0112] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above-described session migration method embodiments and can achieve the same technical effect. To avoid repetition, it will not be described again here.
[0113] It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.
[0114] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.
[0115] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.
[0116] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.
Claims
1. A session migration method, characterized in that, The method includes: In the event of a failure of the first session management function (SMF), the emergency SMF sends a first request to the first user plane function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF, and the first request is used to obtain first information of the first user, wherein the first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF, and the first information includes user identification information and network service information. Based on the first information, establish the correspondence between the first UPF and the first user; When the network service information indicates that the first user is the second user and a target session request is received from the first user, the emergency SMF sends a second request to the second UPF, wherein the second UPF includes at least one of a plurality of first UPFs that correspond to the first user, and the second request is used to obtain target session information related to the first user, wherein the second user includes a user who has activated the Long Term Evolution Voice Bearer (VoLTE) service. Based on the target session information, the emergency SMF responds to the target session request; When the network service information indicates that the first user is a third user, the emergency SMF sends a second message to the authentication management function AMF, wherein the second message is used to notify the AMF to release session resources related to the first user, and the third user includes users who have not activated VoLTE service.
2. The method according to claim 1, characterized in that, After the emergency SMF sends the first request to the first user plane function UPF, the method further includes: Based on the network configuration data of the first SMF, the emergency SMF configures its own network, wherein the network configuration data is sent by the Network Storage Function (NRF).
3. The method according to claim 1, characterized in that, After the emergency SMF responds to the target session request, the method further includes: The emergency SMF sends a first message to the authentication management function AMF, wherein the first message is used to notify the AMF to release session resources associated with the first user.
4. A session migration method, characterized in that, Performed by the Network Storage Function (NRF), the method includes: Receive a fault reporting message sent by the first session management function (SMF), wherein the fault reporting message includes a first cause of the fault in the first SMF and service information carried by the first SMF; In the event that the first cause indicates a temporary failure of the first SMF, an emergency SMF is activated. The emergency SMF is used to send a first request to a first User Plane Function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF. The first request is used to obtain first information of a first user, wherein the first user includes at least one of a plurality of User Terminal Equipment (UEs) corresponding to a plurality of services carried by the first SMF. The plurality of UEs corresponding to the plurality of services carried by the first SMF are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is also used to establish a correspondence between the first UPF and the first user based on the first information. The emergency SMF is also used to obtain the network service information... If the network service information indicates that the first user is the second user and a target session request from the first user is received, a second request is sent to the second UPF, wherein the second UPF includes at least one of a plurality of first UPFs that correspond to the first user. The second request is used to obtain target session information related to the first user, and the second user includes users who have activated VoLTE service. The emergency SMF is also used to respond to the target session request according to the target session information. The emergency SMF is also used to send a second message to the authentication management function AMF if the network service information indicates that the first user is the third user. The second message is used to notify the AMF to release session resources related to the first user, and the third user includes users who have not activated VoLTE service.
5. The method according to claim 4, characterized in that, After activating the emergency SMF, the method further includes: A third message is sent to the emergency SMF, wherein the third message carries network configuration data of the first SMF, and the network configuration data is used by the emergency SMF to configure its own network.
6. A session migration method, characterized in that, Performed by a User Plane Function (UPF), the UPF comprising at least one of a plurality of UPFs associated with a first SMF, wherein the first SMF is at least one of a plurality of SMFs that have failed, the method comprising: Send a first response message to the emergency SMF; In response to a second request sent by the emergency SMF when network service information indicates that the first user is the second user and a target session request from the first user is received, a second response message is sent to the emergency SMF. The first response message carries first information about the first user, who includes at least one of multiple user terminals (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information, which is used to indicate whether the first user has activated the Long Term Evolution (LTE) Voice Bearer (VoLTE) service. The second response message carries target session information related to the first user, which is used by the emergency SMF to respond to the first user's target session request. The second user includes users who have activated the LTE Voice Bearer (VoLTE) service. The emergency SMF is used to establish a correspondence between the UPF and the first user based on the first information; The emergency SMF is also used to send a second message to the authentication management function AMF when the network service information indicates that the first user is a third user. The second message is used to notify the AMF to release session resources related to the first user. The third user includes users who have not activated VoLTE service.
7. A session migration device, characterized in that, The device includes: The first request module is used to send a first request from the emergency SMF to the first user plane function UPF in the event of a failure of the first session management function (SMF). The first UPF includes at least one of a plurality of UPFs associated with the first SMF. The first request is used to obtain first information of the first user. The first user includes at least one of a plurality of user terminals (UEs) corresponding to a plurality of services carried by the first SMF. The first information includes user identification information and network service information. A module is established to establish a correspondence between the first UPF and the first user based on the first information; The second request module is used to send a second request to a second UPF when the network service information indicates that the first user is the second user and a target session request from the first user is received. The second UPF includes at least one of a plurality of first UPFs that correspond to the first user. The second request is used to obtain target session information related to the first user. The second user includes a user who has activated the Long Term Evolution Voice Bearer (VoLTE) service. The response module is used to respond to the target session request by the emergency SMF based on the target session information; The first request module is further configured to, when the network service information indicates that the first user is a third user, send a second message to the authentication management function AMF, wherein the second message is used to notify the AMF to release session resources related to the first user, and the third user includes users who have not activated VoLTE service.
8. A session migration device, characterized in that, The device, applied to network storage function (NRF), includes: The receiving module is used to receive a fault reporting message sent by the first session management function (SMF), wherein the fault reporting message includes a first cause of a fault in the first SMF and service information carried by the first SMF. The control module is configured to activate an emergency SMF when the first cause indicates a temporary failure of the first SMF. The emergency SMF is configured to send a first request to a first User Plane Function (UPF), wherein the first UPF includes at least one of a plurality of UPFs associated with the first SMF. The first request is configured to obtain first information of a first user, wherein the first user includes at least one of a plurality of User Terminal Equipment (UEs) corresponding to a plurality of services carried by the first SMF. The plurality of UEs corresponding to the plurality of services carried by the first SMF are determined based on the service information carried by the first SMF. The first information includes user identification information and network service information. The emergency SMF is further configured to establish a correspondence between the first UPF and the first user based on the first information. The emergency SMF is also configured to... If the service information indicates that the first user is the second user and a target session request from the first user is received, a second request is sent to the second UPF. The second UPF includes at least one of a plurality of first UPFs that correspond to the first user. The second request is used to obtain target session information related to the first user. The second user includes users who have activated the VoLTE service. The emergency SMF is also used to respond to the target session request based on the target session information. The emergency SMF is also used to send a second message to the authentication management function AMF if the network service information indicates that the first user is the third user. The second message is used to notify the AMF to release session resources related to the first user. The third user includes users who have not activated the VoLTE service.
9. A session migration device, characterized in that, An apparatus for use with a User Plane Function (UPF), the UPF comprising at least one of a plurality of UPFs associated with a first SMF, the first SMF being at least one of a plurality of SMFs that have failed, the apparatus comprising: The sending module is used to send the first response message to the emergency SMF; The sending module is further configured to respond to a second request sent by the emergency SMF when the network service information indicates that the first user is the second user and a target session request from the first user is received, by sending a second response message to the emergency SMF. The first response message carries first information about the first user, where the first user includes at least one of multiple user terminals (UEs) corresponding to multiple services carried by the first SMF. The first information includes user identification information and network service information, where the network service information is used to indicate whether the first user has activated the Long Term Evolution (LTE) Voice on Bearer (VoLTE) service. The second response message carries target session information related to the first user, where the target session information is used by the emergency SMF to respond to the target session request from the first user. The second user includes users who have activated the LTE Voice on Bearer (VoLTE) service. The emergency SMF is used to establish a correspondence between the UPF and the first user based on the first information; The emergency SMF is also used to send a second message to the authentication management function AMF when the network service information indicates that the first user is a third user. The second message is used to notify the AMF to release session resources related to the first user. The third user includes users who have not activated VoLTE service.