Core network switching method and device and electronic equipment

Abstract

The invention discloses a core network switching method and device and electronic equipment. The method comprises the following steps: a target mobility management network element stores user plane function tunnel information, and the user plane function tunnel information is used for establishing a data transmission path for switching a target device from a first core network to a second core network; and after the service gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element, the target mobility management network element sends a switching request message carrying user plane function tunnel information to the target next-generation wireless access network. According to the method and the device, the technical problems of reduced switching efficiency and network resource waste caused by signaling interaction redundancy in the current 4 / 5G fusion network switching process are solved.

Description

Technical Field

[0001] This application relates to the field of communication technology, and more specifically, to a core network switching method, apparatus, and electronic equipment. Background Technology

[0002] In the current 4G and 5G network architecture, with network evolution and technology convergence, the handover between the Evolved Packet Core (EPC) and the 5G System (5GS) has become one of the key technologies for ensuring the continuity of user experience. Especially when a user device (UE) moves from a 4G network to a 5G network, or switches between a satellite EPC network and a terrestrial 5GC network, the network needs to efficiently and seamlessly handle the transfer of data streams to guarantee Quality of Service (QoS) and user experience. The handover mechanisms in related technologies have the following main problems: During the handover process from EPS to 5GS, especially during the handover between the satellite EPC network and the terrestrial 5G Core Network (5GC), the entities involved in the network need to perform multiple signaling interactions to establish indirect data forwarding tunnels and 5GS direct data forwarding paths respectively. This repeated tunnel establishment and release process leads to unnecessary network resource consumption, which not only increases network latency but also consumes valuable network resources.

[0003] There is currently no effective solution to the above problems. Summary of the Invention

[0004] This application provides a core network handover method, apparatus, and electronic device to at least solve the technical problem that signaling interaction redundancy exists during the current 4 / 5G converged network handover process, leading to reduced handover efficiency and wasted network resources.

[0005] According to one aspect of the embodiments of this application, a core network handover method is provided, comprising: a target mobility management network element storing user plane function tunnel information, wherein the user plane function tunnel information is used to establish a data transmission path for a target device to handover from a first core network to a second core network; after the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element, the target mobility management network element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network.

[0006] Optionally, the target mobility management network element stores user plane function tunnel information, including: during the process of the target device switching from the first core network to the second core network, the target mobility management network element sends a first request message to the session management function network element or the gateway control function network element, wherein the first request message is a session management request message used to update the protocol data unit; the target mobility management network element receives a first response message corresponding to the first request message sent by the session management function network element or the gateway control function network element, and stores the user plane function tunnel information in the first response message.

[0007] Optionally, the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, including: when a first triggering condition is met, the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, wherein the first triggering condition is the expiration of a timer.

[0008] Optionally, the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, including: when a second triggering condition is met, the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, wherein the second triggering condition is the sending condition indicated in the configuration information of the target mobility management network element, and the sending condition is determined based on the service requirements and network conditions of the target device.

[0009] Optionally, after storing the user plane function tunnel information in the first response message, the method further includes: the target mobility management network element sending a relocation response message carrying the user plane function tunnel information to the source mobility management network element.

[0010] Optionally, after the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, the method further includes: the target mobility management network element receiving a handover notification message sent by the target next-generation radio access network, wherein the handover notification message carries first tunnel information and second tunnel information, the first tunnel information is used for indirect forwarding of downlink data transmission of the tunnel, and the second tunnel information is used for downlink data transmission after the target device is switched to the second core network.

[0011] Optionally, after the target mobility management network element receives the handover notification message sent by the target next-generation radio access network, the method further includes: the target mobility management network element sending a second request message to the session management function network element or the gateway control function network element, wherein the second request message is a session management request message carrying the first tunnel information and the second tunnel information for a protocol data unit session update.

[0012] According to another aspect of the embodiments of this application, a core network handover method is also provided, comprising: after the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element, the target next-generation radio access network receives a handover request message carrying user plane function tunnel information sent by the target mobility management network element, wherein the user plane function tunnel information is used to establish a data transmission path for the target device to handover from the first core network to the second core network.

[0013] Optionally, after the target next-generation radio access network receives a handover request message carrying user plane function tunnel information sent by the target mobility management network element, the method further includes: the target next-generation radio access network sending a handover notification message to the target mobility management network element, wherein the handover notification message carries first tunnel information and second tunnel information, the first tunnel information is used for indirect forwarding of downlink data transmission of the tunnel, and the second tunnel information is used for downlink data transmission after the target device is switched to the second core network.

[0014] According to another aspect of the embodiments of this application, a core network handover method is also provided, comprising: during the handover process of a target device from a first core network to a second core network, after a target mobility management network element sends a handover request message carrying user plane function tunnel information to a target next-generation radio access network, a target function network element receives a second request message sent by the target mobility management network element, wherein the target function network element is a session management function network element or a gateway control function network element, and the second request message is a session management request message carrying first tunnel information and second tunnel information for performing session updates on protocol data units, wherein the first tunnel information is used for indirect forwarding of downlink data transmission of the tunnel, and the second tunnel information is used for downlink data transmission after the target device is handed over to the second core network; the target function network element sends an N4 session modification request message carrying first tunnel information and second tunnel information to a user plane function network element, wherein N4 is the interface between the session management function network element and the user plane function network element.

[0015] According to another aspect of the embodiments of this application, a core network handover apparatus is also provided, comprising: a storage module for storing user plane function tunnel information in a target mobility management network element, wherein the user plane function tunnel information is used to establish a data transmission path for a target device to handover from a first core network to a second core network; and a sending module for sending a handover request message carrying the user plane function tunnel information to a target next-generation radio access network by the target mobility management network element after the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element.

[0016] According to another aspect of the embodiments of this application, a non-volatile storage medium is also provided, wherein a program is stored in the non-volatile storage medium, and the program controls the device where the non-volatile storage medium is located to execute the above-mentioned core network switching method when it runs.

[0017] According to another aspect of the embodiments of this application, an electronic device is also provided, including: a memory and a processor, the processor being configured to run a program stored in the memory, wherein the program executes the above-described core network switching method during runtime.

[0018] According to another aspect of the embodiments of this application, a computer program product is also provided, including computer instructions, which, when executed by a processor, implement the above-described core network switching method.

[0019] In this embodiment, the target mobility management network element stores user plane function tunnel information, which is used to establish a data transmission path for the target device to switch from the first core network to the second core network. After the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element, the target mobility management network element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network. This method, where the serving gateway sends the indirect forwarding tunnel establishment response message to the source mobility management network element, and then the target mobility management network element sends the handover request message carrying the user plane function tunnel information to the target next-generation radio access network, achieves the goal of the target mobility management network element actively controlling the timing of sending the handover request message carrying the user plane function tunnel information to the target next-generation radio access network. This solves the technical problem of signaling interaction redundancy in the current 4 / 5G converged network handover process, which leads to reduced handover efficiency and wasted network resources. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0021] Figure 1 This is a hardware structure block diagram of a computer terminal for implementing a core network handover method according to an embodiment of this application;

[0022] Figure 2 This is a flowchart of a first core network handover method provided according to an embodiment of this application;

[0023] Figure 3 This is a flowchart of the first EPC to 5GS switch according to the embodiments of this application;

[0024] Figure 4This is a flowchart of the second EPC switching to 5GS according to the embodiments of this application;

[0025] Figure 5 This is a flowchart of a second core network handover method provided according to an embodiment of this application;

[0026] Figure 6 This is a flowchart of a third core network switching method provided according to an embodiment of this application;

[0027] Figure 7 This is a network element interaction diagram provided according to an embodiment of this application;

[0028] Figure 8 This is a schematic diagram of the core network switching device provided according to an embodiment of this application. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0030] The information collected in this application embodiment is information and data authorized by the user or fully authorized by all parties. The collection, storage, use, processing, transmission, provision, disclosure and application of the relevant data all comply with the relevant laws, regulations and standards of the relevant regions, and necessary confidentiality measures have been taken. It does not violate public order and good morals, and provides corresponding operation entry points for users to choose to authorize or reject the automated decision results. If the user chooses to reject, the process will proceed to the expert decision-making process.

[0031] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0032] In related technologies, the handover mechanism suffers from the following main problems: During the handover process from EPS to 5GS, especially between the satellite EPC network and the terrestrial 5G Core Network (5GC), the entities involved in the network need to perform multiple signaling interactions to establish indirect data forwarding tunnels and 5GS direct data forwarding paths, respectively. This repeated tunnel establishment and release process leads to unnecessary network resource consumption, which not only increases network latency but also consumes valuable network resources. Therefore, there is a technical problem in the current 4G / 5G converged network handover process: redundant signaling interactions lead to reduced handover efficiency and wasted network resources. To solve this problem, this application provides a related solution, which is described in detail below.

[0033] According to an embodiment of this application, an embodiment of a core network switching method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0034] The methods and embodiments provided in this application can be executed on a computer terminal or similar computing device. Figure 1 A hardware block diagram of a computer terminal for implementing a core network handover method is shown. Figure 1 As shown, the computer terminal 10 may include one or more processors 102 (shown as 102a, 102b, ..., 102n in the figure) 102 (processor 102 may include, but is not limited to, a microprocessor MCU or a programmable logic device FPGA, etc.), a memory 104 for storing data, and a transmission device 106 for communication functions. In addition, it may also include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of a BUS bus), a network interface, a power supply, and / or a camera. Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the aforementioned electronic device. For example, computer terminal 10 may also include... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown.

[0035] It should be noted that the aforementioned one or more processors 102 and / or other data processing circuits are generally referred to herein as "data processing circuits". These data processing circuits may be embodied, in whole or in part, in software, hardware, firmware, or any other combination thereof. Furthermore, the data processing circuits may be a single, independent processing module, or may be integrated, in whole or in part, into any other element within the computer terminal 10. As involved in the embodiments of this application, the data processing circuits serve as processor control (e.g., selection of a variable resistor termination path connected to an interface).

[0036] The memory 104 can be used to store software programs and modules of application software, such as the program instructions / data storage device corresponding to the core network switching method in this embodiment. The processor 102 executes various functional applications and data processing by running the software programs and modules stored in the memory 104, thereby realizing the aforementioned core network switching method. The memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor 102, and these remote memories can be connected to the computer terminal 10 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0037] The transmission device 106 is used to receive or send data via a network. Specific examples of the network described above may include a wireless network provided by the communication provider of the computer terminal 10. In one example, the transmission device 106 includes a Network Interface Controller (NIC), which can connect to other network devices via a base station to communicate with the Internet. In another example, the transmission device 106 may be a Radio Frequency (RF) module, used for wireless communication with the Internet.

[0038] The display can be, for example, a touchscreen liquid crystal display (LCD) that allows the user to interact with the user interface of the computer terminal 10.

[0039] In the above operating environment, this application provides an embodiment of a core network switching method. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Also, although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than that shown here.

[0040] like Figure 2The diagram shown is a flowchart of a core network handover method according to an embodiment of this application, illustrating the process of the target mobility management network element executing the core network handover method of this application embodiment.

[0041] In some embodiments of this application, the first core network is EPC and the second core network is 5GS. Figure 3 This is a flowchart illustrating the first EPC to 5GS handover process according to an embodiment of this application. It demonstrates the EPC to 5GS handover process in related technologies, with the following implementing entities: Source Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Source Mobility Management Entity (MME), which is the core network element responsible for mobility management and session control in 4G LTE networks; Target Access and Mobility Management Function (AMF) element, which, in 5G networks, is responsible for access and mobility management, undertaking most of the functions of the MME in 4G networks, but also introducing new features and efficiency improvements; and Session Management Function / Gateway Control function (SMF / GW-C) element, where GW-C is responsible for control plane session management and data transmission path control in 4G networks. In 5G networks, these responsibilities are transferred to the SMF (Service Data Function), which not only handles session management on the control plane but also introduces more intelligent network resource management and policy control capabilities. The Packet Data Network Gateway User Plane / UserPlane Function (PGW-U / UPF) is the core component for handling user data plane traffic in the 5G network architecture, while the Packet Data Network Gateway User Plane (PGW-U) is the corresponding user data plane entity in the 4G network. The target is the Next Generation Radio Access Network (NG-RAN). The Serving Gateway (SGW) is the bridge between the User Equipment (UE) and the Evolved Packet Core (EPC), responsible for processing and routing user data packets and supporting different types of bearer services. Various implementing entities interact with downlink / uplink user plane data. This includes a preparation phase and an execution phase, with the specific execution process as follows:

[0042] Preparation phase:

[0043] 1-2. When the source E-UTRAN detects that a User Equipment (UE) has entered its coverage area and needs to switch to the 5GS network, the source E-UTRAN initiates a handover request, sending a Handover Required message to the source Mobility Management Element (MME). Handover Required is a control message in mobile communication networks used to trigger a UE to switch from its current serving cell to another cell, including the UE's location information, target cell information, and the UE's service requirements. The source MME refers to the MME in the 4G network. The source MME is responsible for handling all control plane operations related to UE mobility, including but not limited to: handover request processing, target network selection, and signaling interaction.

[0044] 3-4. The source MME selects the target AMF and sends a relocation message (GPRS Tunneling Protocol version 2 - Control, abbreviated as GTPv2-C) to the target AMF.

[0045] 5. When a UE is handing over (whether it is handing over within a 5G network or handing over from 4G to 5G), the target AMF refers to the AMF responsible for access and mobility management after the UE hands over to a new cell or service area. The target AMF sends an Nsmf_PDUSession_UpdateSMContext request to the SMF / GW-C based on each Packet Data Network (PDN) connection. This request includes: the UE EPS PDN Connection on the Evolved Packet Data Network (EPS): In the 4G network, the UE communicates with the external data network through the PDN connection, and the EPS PDN Connection describes the state and attributes of this connection; the initial AMF ID: which refers to the unique identifier of the AMF serving the UE when it first attempts to access the 5G network; data forwarding information: which contains information used to guide how user data packets are forwarded from the source network to the target network during handover, typically including Tunnel Endpoint Identifiers (TEIDs) and IP addresses to achieve continuous data transmission; and the target ID: which refers to the unique identifier of the target network or target node (such as the AMF or RAN) used to correctly locate and contact target network resources during handover.

[0046] In the initial AMF, the address / ID of the SMF / GW-C in the UE context is obtained from step 4. The SMF (in 5G networks) searches for the relevant Packet Data Unit Session (PDU Session) based on the EPS Bearer Context(s). The PDU session is a mechanism in 5G used to describe the data connection between the UE and the data network, equivalent to the role of the EPS bearer in 4G. Based on the configuration and the Direct Forwarding Flag received from the source MME (in 4G networks), the initial AMF determines whether data should be forwarded directly during handover, rather than indirectly via additional hops or entities in the core network. This flag is set by the MME (in 4G networks) and passed to the initial AMF during the handover process. The initial AMF is the AMF that serves the UE when it first attempts to access the 5G network, in order to determine the optimal data forwarding strategy (direct forwarding or indirect forwarding). The initial AMF decides the data forwarding suitability range based on the network configuration and the Direct Forwarding Flag and instructs the SMF whether to perform direct or indirect forwarding.

[0047] 6. SMF / GW-C sends an N4 session modification request to PGW-U / UPF, instructing PGW-U / UPF to allocate a user plane tunnel for a 5G PDUSession.

[0048] 7. The SMF / GW-C returns the Nsmf_PDUSession_UpdateSMContext response from step 5 to the target AMF, carrying the mapped UPF / PGW tunnel info1. UPF Tunnel info: In the 5G network, this is tunnel information associated with the UPF (User Plane Function of the 5G network), containing parameters used to determine how data is transmitted on the 5G user plane. PGW Tunnel Info: In the 4G network, this is tunnel information associated with the PGW-U (User Plane Gateway of the 4G network), used to guide how data is transmitted on the 4G user plane. At this point, the resource preparation for establishing 5GS uplink user plane data is complete.

[0049] 8. The target AMF sends a handover request to the target NG-RAN, carrying the UPF / PGW tunnel info1 from step 7.

[0050] 9. The target NG-RAN sends a handover request confirmation message to the target AMF, carrying the radio access network tunnel information (RAN tunnel info1) allocated by the RAN side. This message is used to establish an indirect user data transmission path from UE (User Equipment) to 5GS core network UPF (User Plane Function), that is, to indirectly forward downlink data transmission through the tunnel.

[0051] 10. The target AMF sends an Nsmf_PDUSession_UpdateSMContext request carrying RAN tunnel info1 to the SMF / GW-C for session updates of Protocol Data Units (PDUs) based on each PDN connection. The request also includes the following parameters: UE EPS PDN Connection, initial AMF ID, data Forwarding information, and TargetID.

[0052] 11. The SMF / GW-C sends an N4 session modification request carrying RAN tunnel info1 to the PGW-U / UPF, interacts with the PGW-U / UPF to perform the N4 modification procedure, and requests the PGW-U tunnel info1 allocated by the PGW-U / UPF. This completes the data forwarding path (indirect tunnel) for 5GS downlink user plane data.

[0053] 12. Return the Nsmf_PDUSession_UpdateSMContext response from step 10, carrying UPF / PGW tunnelinfo1. The returned message contains tunnel information (tunnel info1) from the UPF (User Plane Function) or PGW side.

[0054] 5-12. Prepare handover resources at the target end, performing a handover similar to that in 5GC's N2 (the N2 interface is a key control plane interface between the Next Generation Radio Access Network (NG-RAN) and the Access and Mobility Management Function (AMF)). The AMF will notify each affected SMF, and the SMF will provide QoS and UPF tunnel information to the NG-RAN and the target NG-RAN; simultaneously, the target NG-RAN will acknowledge the PDU session information and provide the tunnel information on the target NG-RAN side to the SMF.

[0055] 13. The target AMF returns a (GTPv2-C) relocation response message (carrying UPF / PGW tunnelinfo1) to the source MME. GTPv2-C is used for signaling interaction between the core network and the radio access network.

[0056] 14. The source MME sends an Indirect Data Forwarding Tunnel Request to the SGW (containing addresses and TEIDs for forwarding), along with UPF / PGW tunnel info1. At this point, the uplink indirect tunnel from the SGW to the PGW-U is established.

[0057] 15. SGW Response Step 10: Send an Indirect Forwarding Tunnel Establishment Response (containing the address of the serving gateway and the service tunnel endpoint identifier for forwarding) to the MME, carrying the tunnel information on the SGW side (SGW Tunnel info1).

[0058] During the execution phase:

[0059] 16. The source MME sends a handover command (SGW tunnel info1) to the source E-UTRAN, carrying SGW tunnel info1. At this point, the indirect forwarding tunnel from the source E-UTRAN to the SGW for indirect tunnel EPS downlink user plane data is established. The handover command contains several components, the specific content and purpose of which are as follows: Target-to-Source transparent container: used to encapsulate specific information of the target network (here, the 5G network), including context details of the UE (User Equipment) in the target network, such as the address of the target AMF, the UE's identity information in the target network, and the access technology of the target network. Bearers subject to forwarding and bearers to be released.

[0060] 17-19. The MME sends a handover command to the UE via the source E-UTRAN, and the UE connects to the new cell: 17. The UE receives the handover command from the E-UTRAN, which is an important signal in the handover process, guiding the UE to perform the handover. 18. The UE synchronizes and updates the cell. 19. The UE confirms the handover with the target NG-RAN, that is, the UE completes synchronization with the new cell and informs the NG-RAN that it has successfully handed over. At this point, the user plane establishment of the UE to the NG-RAN is completed.

[0061] 20-24:20. The target NG-RAN sends a handover message (RAN tunnel info2, another radio access network tunnel information allocated by the RAN side; the 2 here, compared to the 1 in RAN tunnel info1 above, is only to distinguish the radio access network tunnel information allocated by the RAN side at different stages. RAN tunnel info2 is the second tunnel information allocated by the target NG-RAN to the UE after the UE successfully hands over to the target NG-RAN; this new tunnel information is used for 5GS downlink data transmission after the handover) to notify the AMF that the handover has been successful. The target AMF notifies each affected SMF of the handover information, and the SMF completes the establishment of the user plane for 5GS downlink data.

[0062] 21. The target AMF sends a (GTPv2-C forwarding relocation completion notification) to the source MME.

[0063] 22. The target AMF sends an Nsmf_PDUSession_UpdateSMContext request (carrying RANtunnel info2) to the SMF / GW-C. This request is used to update the UE's session information in the 5G network.

[0064] 23. The SMF / GW-C sends an N4 session modification request carrying RAN tunnel info2 to the PGW-U / UPF, and interacts with the PGW-U / UPF to perform the N4 session modification procedure. 24. The SMF / GW-C sends the Nsmf_PDUSession_UpdateSMContext response corresponding to step 22 to the target AMF. User plane establishment for 5GS downlink user plane data.

[0065] 25. The UE synchronizes to the new cell and performs a simplified mobility registration process.

[0066] 26. The source MME sends a UE context release command to the source E-UTRAN to release indirect tunnel resources and E-UTRAN resources.

[0067] 27. SGW and source MME delete indirect forwarding tunnel.

[0068] Steps 1-27 above illustrate the complete EPC to 5GS handover process in related technologies. It can be seen that during the handover process between 4G / 5G converged networks (EPC to 5GS handover), for the 5GC RAN side, due to the establishment of indirect tunnels and 5GS tunnels with PGW-U / UPF, the information provided in the above steps indicates redundancy in the establishment of user plane data paths between NG-RAN, SMF, and GW-U / UPF. In particular, when switching from the satellite EPC network to the terrestrial 5GC network, internal interaction redundancy occurs within the EPC network, reducing handover efficiency. In summary, whether for handover of a single 4G / 5G converged network element or handover of two networks (satellite and terrestrial), related technologies suffer from redundant signaling interaction and low efficiency between NG-RAN, SMF, and GW-U / UPF. Based on the above problems, the method in this application proposes a core network handover method to solve these problems and improve interaction efficiency. The following details the process. Figure 2 The core network switching method is shown.

[0069] exist Figure 2 In step S202, the target mobility management network element stores user plane function tunnel information.

[0070] In the technical solution provided in step S202, the target mobility management network element is specifically the target access and mobility management function network element, namely the target AMF. The user plane function tunnel information is used to establish the data transmission path for the target device to switch from the first core network to the second core network.

[0071] There are several ways to implement the storage of user plane function tunnel information by the target mobility management network element. For example, during the handover process of the target device from the first core network to the second core network, the target mobility management network element sends a first request message to the session management function network element or the gateway control function network element. The first request message is a session management request message used to update the Protocol Data Unit (PDU) (i.e., the aforementioned...). Figure 3 The request in step 5 updates the UE's PDU session management context to prepare the handover path for user plane data. This is an important protocol message used for session management and context updates in 5G networks. The target mobility management network element receives the first response message corresponding to the first request message sent by the session management function network element or gateway control function network element (SMF / GW-C), and stores the user plane function tunnel information in the first response message. The first response message is the one described above. Figure 3The Nsmf_PDUSession_UpdateSMContext response in step 7, as a response to the aforementioned first request message, contains updated PDU session management context information. This includes crucial User Plane Function Tunnel information (UPF Tunnel info), specifically UPF / PGW tunnelinfo1 in step 7. UPF tunnel information defines the transmission path of user data packets in the network, including tunnel endpoint identifiers (TEIDs), IP addresses, etc., ensuring efficient data transmission between the correct user plane nodes. The mapped User Plane Function Tunnel information (UPF Tunnel info) is stored.

[0072] Step S204: The Serving Gateway (SGW) sends an Indirect Forwarding Tunnel Establishment Response Message (i.e., ...) to the source Mobility Management Network Element. Figure 3 Following the message in step 15, the target mobility management element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network (target NG-RAN). The source mobility management element refers to the source MME.

[0073] In the technical solution provided in step S204, there are multiple ways to implement the target mobility management network element sending a handover request message carrying user plane function tunnel information to the target next-generation radio access network. For example, when a first triggering condition is met, the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, wherein the first triggering condition is the expiration of a timer. When a second triggering condition is met, the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, wherein the second triggering condition is the fulfillment of the sending conditions indicated in the configuration information of the target mobility management network element, and the sending conditions are determined based on the service requirements and network conditions of the target device. These are described in detail below.

[0074] Step S204 is to perform the above Figure 3 The improvement to step 8 in the related technology process is that in step 8, the target AMF sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network (target NG-RAN). However, the solution of this application embodiment does not perform step 8, but instead performs it after the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element (i.e., the above). Figure 3The handover request message is sent only after step 15. In the original technical process, the target AMF immediately sends a handover request to the target NG-RAN (step 8) after updating the user plane function tunnel information (step 7). This means that there is a large amount of signaling interaction in the preparation phase before the handover, which not only increases the network load but may also cause handover delays. The improved process postpones step 8 to after step 15, reducing the signaling interaction in the early stage. Since the establishment and confirmation of the indirect tunnel have been completed, the target AMF no longer needs to interact with the target NG-RAN with UPF tunnel information in advance, thereby reducing the signaling load in the handover preparation phase.

[0075] After the serving gateway sends a relocation response message carrying user plane function tunnel information to the source mobility management network (MME), the timing for the target mobility management network element (AMF) to send a handover request message carrying user plane function tunnel information to the target next-generation radio access network (NGR) in this application is initiated by the target AMF. There are several ways to determine when the target AMF sends this handover message, including at least the following two: Under the condition of satisfying a first triggering condition, the target AMF sends a handover request message carrying user plane function tunnel information to the target NRG. The first triggering condition is the expiration of a timer. The timer's start time can be set after receiving the first response message corresponding to the first request message sent by the session management function network element (SMF) or gateway control function network element (GW-C). The timer expiration serves as a triggering condition, allowing the target AMF to actively initiate the sending of a handover request message according to a pre-set time interval (set based on different network environments and UE movement speeds) after completing preliminary preparations (such as interaction with the source MME, acquisition and storage of tunnel information). This mechanism considers the timeliness and stability of network handover, ensuring that the next operation is performed at an appropriate time, avoiding handover attempts that are too early or too late.

[0076] When the second triggering condition is met, the target mobility management network element (AMF) sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network (NG-RAN). The second triggering condition is the fulfillment of the transmission conditions indicated in the target AMF's configuration information. These transmission conditions are determined based on the target device's service requirements (e.g., the target AMF monitors the UE's service requirements, identifies the type of service the UE is using (e.g., video streaming, data download, etc.) and associated QoS configuration), and network conditions (including the target NG-RAN's resource usage, link quality, signal strength, etc.). When the UE's service requirements change or reach a certain threshold (e.g., increased real-time requirements or bandwidth exceeding the current network capacity) and the target NG-RAN's network conditions meet the handover conditions (e.g., sufficient resources, stable signal), the target AMF, based on the results output by the service requirement analysis module in the configuration information, decides to immediately send a handover request. Furthermore, possible variations besides the two methods described above should also be included within the scope of this application. Delaying the timing of the target AMF sending the handover request allows for a one-time, efficient transmission after all necessary context and tunnel information are ready. In the traditional process, sending a handover request in advance may result in the target NG-RAN not being ready to receive or process tunnel information, leading to unnecessary waiting or additional signaling round trips. The improved process ensures that all relevant network elements (such as SMF, UPF, SGW, and the target NG-RAN) are synchronized and ready, thereby accelerating the establishment of data forwarding paths during the actual handover process and improving the overall efficiency of the handover.

[0077] After storing the user plane function tunnel information in the first response message, another improvement to the method in this application embodiment is that after the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, the target mobility management network element receives a handover notification message sent by the target next-generation radio access network (corresponding to the above). Figure 3 Step 20), wherein the handover notification message sent by the target next-generation radio access network carries first tunnel information (i.e., the aforementioned RAN tunnel info1) and second tunnel information (i.e., the aforementioned RAN tunnel info2). The first tunnel information is used for indirectly forwarding downlink data transmission of the tunnel, and the second tunnel information is used for downlink data transmission after the target device is switched to the second core network. Figure 3As can be seen, the handover notification message in step 20 of the related technology only carries RAN tunnel info2, while the handover request message of this application contains two types of tunnel information. Compared with the related technology where the target NG-RAN only carries a single RAN tunnel info2 in the handover notification message, the improvement of this application lies in enhancing the handover notification message to carry both sets of tunnel information simultaneously. This avoids the risk of data transmission interruption during handover and simplifies the UE's rapid access in the new network, improving overall handover efficiency and data transmission quality.

[0078] After receiving the handover notification message from the target next-generation radio access network, the target mobility management network element sends a second request message (corresponding to the above) to the session management function (SMF) or gateway control function (GW-C) network element. Figure 3 The message in step 22), wherein the second request message is a session management request message for updating the protocol data unit session, carrying the first tunnel information and the second tunnel information. Figure 3 It is known that the session management request message for protocol data unit session update in step 20 of the related technology only carries RAN tunnel info2, while the second request message of this application contains two types of tunnel information.

[0079] Figure 4 This is a flowchart illustrating the second EPC to 5GS switch according to the embodiments of this application. Figure 2 The complete process of the core network handover method shown is as follows: Figure 4 Same as 1-7 in Figure 3 In steps 1-7, after receiving the response from the SMF / GW-C in step 7, the target AMF saves its mapped user plane function tunnel information (i.e., the target mobility management network element stores user plane function tunnel information). The rest is omitted. Figure 3 Steps 8-12 in the previous steps are directly followed by step 13, which sends a relocation response to the source MME based on the UPF tunnel info1 saved in step 7. Step 8 is performed after the serving gateway sends the establishment of indirect forwarding tunnel response message to the source mobility management network element, specifically after step 19 (corresponding to the above-mentioned handover request message carrying user plane function tunnel information to the target next-generation radio access network after the serving gateway sends the establishment of indirect forwarding tunnel response message to the source mobility management network element). Figure 4 14-19 in the same Figure 3 14-19 in the middle. Figure 4 Step 20 in the middle is relative to Figure 3Step 20 in the process includes RAN tunnel info1 (i.e., the first tunnel information (i.e., the RAN tunnel info1 mentioned above) and the second tunnel information (i.e., the RAN tunnel info2 mentioned above) carried in the handover notification message sent by the target next-generation radio access network), with the addition of RAN tunnel info1. Figure 4 Step 21 is the same as in Figure 3 Step 21 in the process. Figure 4 Steps 22 and 23 in the middle are relative to Figure 3 Steps 22 and 23 both added RAN tunnel info1.

[0080] Figure 5 This is a flowchart of a second core network handover method provided according to an embodiment of this application, including:

[0081] In step S502, after the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element, the target next-generation radio access network receives a handover request message carrying user plane function tunnel information sent by the target mobility management network element. The user plane function tunnel information is used to establish a data transmission path for the target device to handover from the first core network to the second core network.

[0082] In the technical solution provided in step S502, after the target next-generation radio access network receives the handover request message carrying user plane function tunnel information sent by the target mobility management network element, the target next-generation radio access network sends a handover notification message to the target mobility management network element. The handover notification message carries first tunnel information (i.e., the aforementioned RANtunnel info1) and second tunnel information (i.e., the aforementioned RAN tunnel info2). The first tunnel information is used to indirectly forward downlink data transmission of the tunnel, and the second tunnel information is used to transmit downlink data after the target device is switched to the second core network.

[0083] It should be noted that, Figure 5 The flowchart shown is for illustrating the second core network handover method. Figure 2 The first core network switching method shown and Figure 4 The second EPC switchover to 5GS flowchart shown represents an improvement on the target next-generation radio access network (target NG-RAN) side, therefore... Figure 2 In the first core network switching method, steps S202-S204 and... Figure 4 The relevant explanations also apply to this second core network switching method, and will not be repeated here.

[0084] Figure 6This is a flowchart of a third core network handover method provided according to an embodiment of this application, including:

[0085] In step S602, during the handover process from the first core network to the second core network by the target mobility management network element, after the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, the target function network element receives a second request message sent by the target mobility management network element. This second request message is the same message as the second request message that appears in steps S202-S204.

[0086] In the technical solution provided in step S602, the target functional network element is a session management functional network element or a gateway control functional network element. The second request message is a session management request message carrying the above-mentioned RAN tunnel info1 and the second tunnel information (i.e., the above-mentioned RAN tunnel info2) for updating the protocol data unit. The first tunnel information is used to indirectly forward the downlink data transmission of the tunnel, and the second tunnel information is used to switch the target device to the downlink data transmission after switching to the second core network.

[0087] In step S604, the target functional network element sends an N4 session modification request message carrying the first tunnel information and the second tunnel information to the user plane functional network element, wherein N4 is the interface between the session management functional network element and the user plane functional network element.

[0088] It should be noted that, Figure 6 The flowchart shown is for demonstrating the third core network switching method. Figure 2 The first core network switching method shown and Figure 4 The second EPC to 5GS switchover flowchart shown is an improvement on the target functional network element (SMF / GW-C) side, therefore... Figure 2 Steps S202-S204 of the first core network switching method shown are as follows: Figure 4 The relevant explanations also apply to this third core network switching method, and will not be repeated here.

[0089] Figure 7 This is a network element interaction diagram provided according to an embodiment of this application. 1 and 2 represent the identifiers of network function modules; 1 represents the user plane, and 2 represents the control plane. Green link: E-UTRAN, SGW, PGW-U / UPF, NG-RAN indicates that the service data of 4G user equipment originates from the 4G base station, is forwarded through the SGW to PGW-U, and finally accesses NG-RAN. Red link: NG-RAN to PGW-U / UPF indicates that the service data of 5G users accesses the UPF of the 5G core network for processing, or is then forwarded by the UPF to an external data network.

[0090] Figure 8 This is a schematic diagram of the core network switching device according to an embodiment of this application, including:

[0091] Storage module 802 is used by the target mobility management network element to store user plane function tunnel information, wherein the user plane function tunnel information is used to establish the data transmission path for the target device to switch from the first core network to the second core network.

[0092] The storage module 802 is also used to send a first request message to the session management function network element or the gateway control function network element during the process of the target device switching from the first core network to the second core network. The first request message is a session management request message used to update the protocol data unit. The target mobility management network element receives the first response message corresponding to the first request message sent by the session management function network element or the gateway control function network element, and stores the user plane function tunnel information in the first response message.

[0093] The sending module 804 is used to send a handover request message carrying user plane function tunnel information to the target next-generation radio access network after the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element.

[0094] The sending module 804 is further configured to, upon meeting a first triggering condition, send a handover request message carrying user plane function tunnel information to the target next-generation radio access network, wherein the first triggering condition is the expiration of a timer. Upon meeting a second triggering condition, the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, wherein the second triggering condition is meeting the sending conditions indicated in the configuration information of the target mobility management network element, and the sending conditions are determined based on the service requirements and network conditions of the target device.

[0095] The sending module 804 is also used to store the user plane function tunnel information in the first response message, and then send a relocation response message carrying the user plane function tunnel information to the source mobility management element.

[0096] The sending module 804 is further configured to, after the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, receive a handover notification message sent by the target next-generation radio access network. The handover notification message carries first tunnel information and second tunnel information. The first tunnel information is used to indirectly forward downlink data transmission of the tunnel, and the second tunnel information is used to transmit downlink data after the target device is switched to the second core network.

[0097] The sending module 804 is also used to send a second request message to the session management function network element or the gateway control function network element, wherein the second request message is a session management request message carrying the first tunnel information and the second tunnel information for a protocol data unit session update.

[0098] It should be noted that, Figure 8 The core network switching device shown is used to perform... Figure 2 The core network switching method shown is therefore Figure 2 The explanations and descriptions in the core network switching method also apply to the switching device of this core network, and will not be repeated here.

[0099] It should be noted that the modules in the switching device of the core network can be program modules (e.g., a set of program instructions to implement a specific function) or hardware modules. For the latter, they can be in the following forms, but are not limited to these: each of the above modules is in the form of a processor, or the functions of each of the above modules are implemented by a processor.

[0100] This application also provides a non-volatile storage medium, which includes a stored program, wherein, when the program is running, it controls the device where the non-volatile storage medium is located to execute the core network switching method in any of the above embodiments.

[0101] This application also provides an electronic device, which includes a processor for running a program, wherein the core network switching method of any of the above embodiments is executed during program execution.

[0102] According to another aspect of the embodiments of this application, a computer program product is also provided, including a computer program that, when executed by a processor, implements the core network switching method in any of the above embodiments.

[0103] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0104] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0105] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0106] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0107] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to related technologies, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0108] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A core network switching method, characterized in that, include: The target mobility management network element stores user plane function tunnel information, wherein the user plane function tunnel information is used to establish a data transmission path for the target device to switch from the first core network to the second core network; After the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management element, the target mobility management element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network.

2. The method according to claim 1, characterized in that, The target mobility management network element stores user plane function tunnel information, including: During the process of the target device switching from the first core network to the second core network, the target mobility management network element sends a first request message to the session management function network element or the gateway control function network element, wherein the first request message is a session management request message for performing session updates on protocol data units; The target mobility management network element receives a first response message corresponding to the first request message sent by the session management function network element or the gateway control function network element, and stores the user plane function tunnel information in the first response message.

3. The method according to claim 1, characterized in that, The target mobility management network element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network, including: When a first triggering condition is met, the target mobility management network element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network, wherein the first triggering condition is the expiration of a timer.

4. The method according to claim 1, characterized in that, The target mobility management network element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network, including: When the second triggering condition is met, the target mobility management network element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network. The second triggering condition is the fulfillment of the sending condition indicated in the configuration information of the target mobility management network element, and the sending condition is determined based on the service requirements and network conditions of the target device.

5. The method according to claim 2, characterized in that, After storing the user plane function tunnel information from the first response message, the method further includes: The target mobility management network element sends a relocation response message carrying the user plane function tunnel information to the source mobility management network element.

6. The method according to claim 2, characterized in that, After the target mobility management network element sends a handover request message carrying the user plane function tunnel information to the target next-generation radio access network, the method further includes: The target mobility management network element receives a handover notification message sent by the target next-generation radio access network. The handover notification message carries first tunnel information and second tunnel information. The first tunnel information is used to indirectly forward downlink data transmission through the tunnel, and the second tunnel information is used to transmit downlink data after the target device is switched to the second core network.

7. The method according to claim 6, characterized in that, After the target mobility management network element receives the handover notification message sent by the target next-generation radio access network, the method further includes: The target mobility management network element sends a second request message to the session management function network element or the gateway control function network element, wherein the second request message is a session management request message carrying the first tunnel information and the second tunnel information for a protocol data unit session update.

8. A core network switching method, characterized in that, include: After the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management network element, the target next-generation radio access network receives a handover request message carrying user plane function tunnel information sent by the target mobility management network element. The user plane function tunnel information is used to establish a data transmission path for the target device to handover from the first core network to the second core network.

9. The method according to claim 8, characterized in that, After the target next-generation radio access network receives a handover request message carrying user plane function tunnel information sent by a target mobility management network element, the method further includes: The target next-generation radio access network sends a handover notification message to the target mobility management network element. The handover notification message carries first tunnel information and second tunnel information. The first tunnel information is used to indirectly forward downlink data transmission through the tunnel, and the second tunnel information is used to handle downlink data transmission after the target device is switched to the second core network.

10. A core network switching method, characterized in that, include: During the process of the target device switching from the first core network to the second core network, after the target mobility management network element sends a handover request message carrying user plane function tunnel information to the target next-generation radio access network, the target function network element receives a second request message sent by the target mobility management network element. The target function network element is a session management function network element or a gateway control function network element. The second request message is a session management request message carrying first tunnel information and second tunnel information for updating the protocol data unit. The first tunnel information is used for indirect forwarding of downlink data transmission of the tunnel, and the second tunnel information is used for downlink data transmission after the target device is switched to the second core network. The target function network element sends an N4 session modification request message carrying the first tunnel information and the second tunnel information to the user plane function network element, wherein N4 is the interface between the session management function network element and the user plane function network element.

11. A core network switching device, characterized in that, include: The storage module is used by the target mobility management network element to store user plane function tunnel information, wherein the user plane function tunnel information is used to establish a data transmission path for the target device to switch from the first core network to the second core network; The sending module is configured to, after the serving gateway sends an indirect forwarding tunnel establishment response message to the source mobility management element, send a handover request message carrying the user plane function tunnel information to the target next-generation radio access network.

12. A non-volatile storage medium, characterized in that, The non-volatile storage medium stores a program, wherein when the program runs, it controls the device where the non-volatile storage medium is located to execute the core network switching method according to any one of claims 1 to 7, or the core network switching method according to any one of claims 8 to 9, or the core network switching method according to claim 10.

13. An electronic device, characterized in that, include: A memory and a processor, the processor being configured to run a program stored in the memory, wherein the program, when running, executes the core network switching method according to any one of claims 1 to 7, or executes the core network switching method according to any one of claims 8 to 9, or executes the core network switching method according to claim 10.

14. A computer program product comprising computer instructions, characterized in that, When the computer instructions are executed by the processor, they implement the core network switching method of any one of claims 1 to 7, or implement the core network switching method of any one of claims 8 to 9, or implement the core network switching method of claim 10.

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