Message forwarding method, UPF selection method, electronic equipment and storage medium
By establishing a direct communication session link between the UE and UPF in the 5G architecture, the message communication latency problem caused by ePDG devices is solved, achieving more efficient message transmission and secure and reliable communication.
Patent Information
- Application Number
- CN202411158477.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-22
- Publication Date
- 2026-03-03
AI Technical Summary
Under the 5G architecture, message communication transmission latency is relatively high, mainly because the ePDG device, as an intermediate device, undertakes a large amount of information transmission, which leads to increased network transmission latency.
The UE sends a communication capability identifier to the ePDG, indicating support for control plane and media plane separation. The SMF selects a target UPF that supports control plane and media plane separation, and uses the target UPF's address information and SPI to directly establish a communication session link between the UE and the UPF, avoiding message forwarding through the ePDG.
It effectively reduces transmission latency in message communication, improves communication security and reliability, and reduces the forwarding pressure on ePDG.
Smart Images
Figure CN121603891A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of communication technology, and in particular to a message forwarding method, a UPF selection method, an electronic device, and a storage medium. Background Technology
[0002] In 5G architecture, message communication typically begins after the User Equipment (UE) initiates a message communication request. After the Session Management Function (SMF) confirms the matching User Plane Function (UPF) for this message communication, the UE first sends the message information to the Evolved Packet Data Gateway (ePDG). The ePDG then forwards the message information to the UPF for further forwarding, ultimately delivering the message to the target receiver. However, this forwarding method places a heavy burden of information transmission on the ePDG, which, as an intermediary, can lead to higher network latency due to limitations inherent in the ePDG itself, especially as the amount of information increases. Summary of the Invention
[0003] This application provides a message forwarding method, a UPF selection method, an electronic device, and a storage medium, aiming to solve the technical problem of high latency in message communication transmission.
[0004] In a first aspect, embodiments of this application provide a message forwarding method, the method being applied to a user equipment (UE), the method comprising: Send a first message to the evolved packet data gateway (ePDG), the first message carrying the communication capability identifier of the UE, the communication capability identifier being used to characterize that the UE supports control plane and media plane separation; Receive a second message sent by the ePDG, the second message carrying the address information and security parameter index SPI corresponding to the target user plane function UPF, the target UPF supporting control plane and media plane separation; Generate a first target message based on the SPI of the target UPF; Based on the address information of the target UPF, the first target packet is directly forwarded to the target UPF.
[0005] Secondly, embodiments of this application provide a message forwarding method, the method being applied to a UPF, the method comprising: The UE receives a third message sent by the Session Management Function (SMF). The third message carries the UE's address information, SPI, and direct forwarding identifier. The direct forwarding identifier is generated based on the UE's communication capability identifier, which indicates that the UE supports control plane and media plane separation. Generate a second target message based on the UE's SPI; Based on the direct forwarding identifier and the UE's address information, the second target message is directly forwarded to the UE.
[0006] Thirdly, embodiments of this application provide a method for selecting a UPF, the method being applied to an SMF, the method comprising: The system receives a fifth message sent by the ePDG, which carries the UE's address information and a direct forwarding identifier. The direct forwarding identifier is generated based on the UE's communication capability identifier, which indicates that the UE supports control plane and media plane separation. The target UPF that supports control plane and media plane separation is determined based on the direct forwarding identifier, and a third message is sent to the target UPF. The third message carries the UE's address information, SPI, and direct forwarding identifier. The UE's SPI is used to generate a second target message, and the direct forwarding identifier is used to instruct the target UPF to directly forward the second target message to the UE based on the UE's address information.
[0007] Fourthly, embodiments of this application provide an electronic device, including: at least one processor; at least one memory for storing at least one program; and when at least one of the programs is executed by at least one of the processors, implementing the packet forwarding method as described in the first aspect, or the packet forwarding method as described in the second aspect, or the UPF selection method as described in the third aspect.
[0008] Fifthly, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the message forwarding method as described in the first aspect, or the message forwarding method as described in the second aspect, or the UPF selection method as described in the third aspect.
[0009] According to the scheme implemented in this application, when a UE wants to connect to a message communication network, the UE sends a communication capability identifier carrying the UE to the ePDG to indicate that the UE can support control plane and media plane separation. This allows the ePDG to select a target UPF that also supports control plane and media plane separation via the SMF. Furthermore, taking advantage of the characteristic that a UE supporting control plane and media plane separation can modify the address information of the next node in the message information, during the real-time call phase after receiving the address information of the target UPF and the SPI, the UE can further realize the direct transmission of the first target message to the target UPF using the target UPF's address information and the SPI as identifiers. This eliminates the need to forward the message information in the actual call through the ePDG, thereby effectively reducing the transmission latency in message communication. Attached Figure Description
[0010] Figure 1 This is a schematic diagram of the architecture of a 5G system provided in an embodiment of this application.
[0011] Figure 2 This is a schematic diagram of a UE1 access message communication network provided in an embodiment of this application.
[0012] Figure 3 This is a schematic diagram of a UE2 access message communication network provided in an embodiment of this application.
[0013] Figure 4 This is a flowchart of a real-time call between UE1 and UE2 provided in an embodiment of this application.
[0014] Figure 5 This is a flowchart illustrating a message forwarding method applied to a UE, as provided in an embodiment of this application.
[0015] Figure 6 This is a schematic diagram of a data structure for a communication capability identifier provided in an embodiment of this application.
[0016] Figure 7 This is a schematic diagram of the data structure of a direct forwarding identifier and a UE's SPI provided in an embodiment of this application.
[0017] Figure 8 This is a flowchart illustrating a method for selecting UPF messages in SMF, provided in an embodiment of this application.
[0018] Figure 9 This is a flowchart illustrating a message forwarding method applied to UPF provided in an embodiment of this application.
[0019] Figure 10 This is a flowchart illustrating a message forwarding method applied to UPF provided in an embodiment of this application.
[0020] Figure 11 This is a schematic diagram of a message forwarding process provided in an embodiment of this application.
[0021] Figure 12 This is a flowchart of a UE responding to a switch of AP, provided in an embodiment of this application.
[0022] Figure 13 This is a schematic diagram of an electronic device provided in an embodiment of this application. Detailed Implementation
[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining this application and are not intended to limit this application.
[0024] The 5G system architecture is defined as supporting data connectivity and services, enabling deployments to utilize technologies such as Network Functions Virtualization (NFV) and Software-Defined Networking (SDN).
[0025] Figure 1 This is a schematic diagram of a 5G system architecture. (Example) Figure 1 As shown, the 5G system architecture includes many interconnected functional modules. Among them, the network functions (NFs) related to the Session Management Function (SMF) include: Access and Mobility Management Function (AMF), Unified Data Management (UDM), Policy Control Function (PCF), User Plane Function (UPF), and Evolved Packet Data Gateway (ePDG).
[0026] The AMF (Active Message Provider) is the endpoint for the Non-Access Stratum (NAS) signaling interface (N1) and the Radio Access Network (RAN) signaling interface (N2). It is responsible for NAS message encryption and integrity, as well as registration, access, mobility, authentication, and SMS transmission. Furthermore, when interacting with the Evolved Packet System (EPS) network, the AMF is also responsible for allocating the Evolved Packet System Bearer Identifier (EPS Bearer Id).
[0027] User-defined domain (UDM) is a key network function in the 5G core network, primarily responsible for managing and storing user identity and subscription data. UDM is an important component of the 5G network architecture, inheriting and developing the functions of the Home Subscriber Server (HSS) in 4G networks while adding new features to adapt to the needs of 5G networks.
[0028] PCF is a key network function in the 5G core network. Its main role is to manage and provide policy decisions to control network behavior and resource allocation. PCF is responsible for formulating and implementing a series of policies that determine the Quality of Service (QoS), access control, and data flow processing methods of User Equipment (UE).
[0029] User Provider Function (UPF) is a key network function in the 5G core network, primarily responsible for handling data traffic in the user plane (i.e., the data plane). UPF is an important component of the 5G network architecture, providing a data path between the UE and the Data Network (DN) and performing functions related to data transmission.
[0030] ePDG is a network component, primarily defined in 3GPP standards, used to support interoperability between legacy 3G Universal Mobile Telecommunications System (UMTS) networks and the Evolved Packet Core (EPC). In other words, ePDG acts as a bridge, enabling user equipment in UMTS networks to seamlessly access LTE / EPC networks and enjoy the services provided by the latter. This is particularly important for operators deploying both 3G and 4G networks, as it allows users to move seamlessly between these networks without interrupting ongoing data sessions.
[0031] Message communication is a data transmission method in which message information is encapsulated into one or more complete data packets and sent from the source node to the destination node via the network. These packets contain complete address and control information to ensure accurate data transmission from the sender to the receiver. Based on the 5G architecture described above, the relevant message communication transmission process will be further described below.
[0032] Figure 2 This is a schematic diagram illustrating the process of a UE1 accessing a message communication network according to an embodiment of this application. Figure 2 As shown, based on the aforementioned 5G architecture, in the relevant message communication transmission technology, after UE1 initiates a message communication request, UE1 first establishes an IKE tunnel with ePDG via the IKESA_INIT (IKE Security Association Initialization) message. Specifically, this includes: UE sending an IKE_AUTH Request message to ePDG to authenticate UE1 and confirm its key; and after successful authentication and key confirmation, ePDG sending an IKE_AUTH Response message to UE1 to establish the IKE communication tunnel.
[0033] The IKESA_INIT message is the initial message used in the Internet Key Exchange (IKE) protocol to initialize the IKE Security Association (IKE SA).
[0034] In addition, an IKE tunnel refers to a secure channel established through the IKE protocol for key exchange and security policy negotiation between two endpoints.
[0035] The IKE_AUTH Request message is an important message in the IKE protocol used for authentication and key verification. It typically carries UE1's identity information, authentication data (such as a digital signature or hash value), and key verification information. The IKE_AUTH Response message is a reply confirmation message corresponding to the IKE_AUTH Request message.
[0036] like Figure 2 As shown, after receiving the IKE_AUTH Request message from UE1, the ePDG sends a Diameter Extensible Authentication Protocol (Diameter EAP) message to the Authentication, Authorization, and Accounting (AAA) server to request authentication of UE1's identity information. After successful authentication by the AAA server, the AAA server sends a Diameter EAP_Success message to the ePDG to indicate that the authentication request was successful.
[0037] Next, the ePDG sends a Create Session Request message to the SMF to request the SMF to create a new data session for UE1 so that UE1 can access the message communication network through the ePDG.
[0038] Then, after receiving the Create Session Request message from the ePDG, the SMF and UPF1 establish a session data path between the ePDG and UPF1 through Packet Forwarding Control Protocol Session Establishment (PFCP Session Establishment) information. Specifically, this includes: the SMF sending a PFCP Session Modification Request message to UPF1 to update the data path on the UPF, thereby adapting to the session communication between the UPF and the ePDG; after receiving the PFCP Session Modification Request message from the SMF and modifying the relevant parameters of the data path, UPF1 sends a PFCP Session Modification Response message to the SMF to notify the SMF that the changed parameters in the PFCP Session Modification Request message received from the SMF have been successfully applied.
[0039] After receiving the PFCP Session Modification Response information from UPF1, SMF sends a Create Session Response message to ePDG to confirm that the session link allocated to UE1 has been established.
[0040] After receiving the Create Session Response message from the SMF, the ePDG sends an IKE_AUTHResponse (IKE authentication response) message to UE1 to complete the construction of the IKE communication tunnel, thereby enabling UE1 to access the message communication network.
[0041] Figure 3 This is a schematic diagram of the UE2 access message communication network provided in an embodiment of this application. For example... Figure 3 As shown, similar to UE1 connecting to the message communication network, UE2 connects to... Figure 2 Similar steps are taken to establish a session link with UPF2 to access the message communication network.
[0042] Figure 4 This is a flowchart of a real-time call between UE1 and UE2 provided in an embodiment of this application. Based on... Figure 2 , Figure 3As shown, after UE1 and UE2 access the message communication network, UE1 sends and receives voice messages to UPF1 via ePDG, and UE2 sends and receives voice messages to UPF2 via ePDG; then UPF1 and UPF2 interact with voice messages through IMS (IP Multimedia Subsystem) to enable UE1 and UE2 to communicate.
[0043] As mentioned above Figures 2 to 4 In the message communication transmission method described in the related technology, during real-time message communication transmission, all message information sent from the UE needs to be forwarded by the ePDG. This causes the ePDG to bear the message forwarding of a large number of message information in the message communication network, making the ePDG a performance bottleneck in the message communication network. When the number of message information increases, the information transmission delay in the message communication network is likely to increase due to the limitations of the ePDG device itself, thus posing a risk of high information transmission delay in the message communication network.
[0044] In view of this, based on Figure 1 The 5G system architecture shown in this application provides a message forwarding method, a UPF selection method, an electronic device, and a storage medium, aiming to solve the technical problem of high latency in message communication transmission. Since the message forwarding method and UPF selection method provided in this application involve the execution description of multiple application entities in the 5G system architecture, the following will provide a comprehensive description of this solution based on the step flow of multiple execution entities.
[0045] For example, when a UE responds to message forwarding, in order to further improve the transmission efficiency of message communication and reduce the transmission latency during message communication, it is necessary to pre-establish a direct communication session link between the UE and the UPF through the ePDG and SMF. This eliminates the need for message forwarding via the ePDG during the UE's real-time call, effectively reducing the transmission latency during the real-time call. The process of establishing this communication session link will be further described below.
[0046] Figure 5 This is a flowchart illustrating a message forwarding method provided in an embodiment of this application. This method can be applied to a User Equipment (UE) and executed by the UE. Figure 5 As shown, the method includes steps S110 to S140.
[0047] S110, Send the first message to the evolved packet data gateway (ePDG).
[0048] Step S110 will be described further below.
[0049] When a UE needs to access a message communication network, it first sends a first message (i.e., an IKE_AUTH Request message) to the evolved Packet Data Gateway (ePDG) for UE authentication and key confirmation. This first message carries the UE's identity information, authentication data, and key confirmation information, etc., so that the ePDG can authenticate the UE and establish a session link, enabling the UE to access the message communication network. Furthermore, the first message contains an identifier indicating that the UE can support control plane and media plane separation, signifying that the UE can adaptively modify the target address of the next node in the message transmission.
[0050] For example, UE identity information includes UE identification information, such as International Mobile Subscriber Identity (IMSI), International Mobile Equipment Identity (IMES), etc., or it can be UE address information; UE authentication data includes random numbers generated by the UE segment for generating authentication vectors, authentication tokens containing information such as timestamps and serial numbers, etc., or it can be the UE's Security Parameter Index (SPI); UE key confirmation information includes information on whether the key confirmation between the UE and ePDG is within the valid time. It can be understood that an SPI is an identifier used to uniquely identify a security association, which defines the security policy between two endpoints, including encryption algorithms, authentication methods, etc.
[0051] Figure 6 This is a schematic diagram of a data structure for a communication capability identifier provided in an embodiment of this application. For example... Figure 6 As shown, the information element of the communication capability identifier is Control-plane and User-plane Separation (CUSeparate), and the data type of the communication capability identifier is boolean. Its conditions can be adaptively selected as needed in practical applications. This communication capability identifier is used to indicate whether the UE supports control plane and media plane separation.
[0052] Understandably, the UE's control plane is responsible for signaling exchange and session management, such as establishing, modifying, and releasing sessions; the UE's media plane is responsible for actual data transmission, such as voice, video, and data stream transmission. In an architecture where the control plane and media plane are separated, the UE can directly send packets to the target device by modifying the destination address of the next packet.
[0053] Similar to the UE, in an architecture where the control plane and media plane are separated, the UPF can also directly send the message to the target device by modifying the target address of the next message.
[0054] When the ePDG receives the first message from the UE, it generates a Diameter EAP (Authentication Request) message based on the UE's identity information and authentication data, and sends the Diameter EAP message to the AAA server for UE authentication. After the AAA server verifies the Diameter EAP, it sends a DiameterEAP_Success message to the ePDG to indicate that the UE's information authentication was successful.
[0055] For example, after receiving a Diameter EAP message, the AAA server parses the attribute-value pairs (AVPs) in the Diameter EAP message. These AVPs contain the UE's identity information, authentication data, etc. Then, the AAA server checks the integrity of the Diameter EAP message, such as ensuring that the message signature is correct and the source is legitimate. Next, after confirming that everything is correct, the AAA server generates a Diameter EAP_Success message to indicate that the Diameter EAP authentication is successful.
[0056] After the ePDG receives the Diameter EAP_Success from the AAA server, it determines that the UE can support control plane and media plane separation based on the communication capability identifier. Then, it generates a direct forwarding identifier to determine the target User Plane Function (UPF) that supports control plane and media plane separation. It also obtains the UE's SPI, and then generates a fifth message (i.e., a Create Session Request message) based on the direct forwarding identifier, the UE's SPI, and session creation information. This fifth message is sent to the SMF, allowing the SMF to select a target UPF that also supports control plane and media plane separation from multiple UPFs based on the direct forwarding identifier. Finally, it generates link modification parameters for the communication session link between the UE and the UPF based on the session creation information in the fifth message.
[0057] For example, link modification parameters include QoS parameters, UE address information, endpoint identifiers of new communication session links, etc.
[0058] Figure 7 This is a schematic diagram of the data structure of a direct forwarding identifier and a UE's SPI provided in an embodiment of this application. Figure 7As shown, the direct forwarding identifier's information element is CUSeparate, and its data type is boolean. Its condition can be adaptively selected as needed in practical applications. This direct forwarding identifier indicates whether the selected UPF supports control plane and media plane separation. Furthermore, the UE's SPI's information element is SPI, and its data type is int. Its condition can be adaptively selected as needed in practical applications. This UE's SPI is used to represent the UE's SPI information.
[0059] For example, after the SMF receives the fifth message from the ePDG, it will execute the Select UPF method. Figure 8 This is a flowchart illustrating a method for selecting UPF messages provided in an embodiment of this application. This method can be applied to the Session Management Function (SMF) and executed by the SMF. Figure 8 As shown, the method includes steps S210 to S220.
[0060] S210, Receive the fifth message sent by ePDG.
[0061] S220. Determine the target UPF that supports control plane and media plane separation based on the direct forwarding identifier, and send a third message to the target UPF.
[0062] Steps S210 to S220 are described in detail below.
[0063] For example, after receiving the fifth message (i.e., the Create Session Request message) sent by the ePDG, the SMF obtains the UE's address information, UE's SPI, direct forwarding identifier, and link modification parameters carried in the fifth message. Next, based on the direct forwarding identifier used to characterize the UPF that needs to support control plane and media plane separation, the SMF selects from multiple UPFs that can support control plane and media plane separation and has available communication resources, i.e., can establish a communication session link with the UE at the current moment, as the target UPF.
[0064] Then, the SMF generates a third message (i.e., the PFCP Session Establishment message) based on the UE's address information, UE's SPI, direct forwarding identifier, and link modification parameters, and sends the third message to the selected target UPF. This allows the target UPF to update the data path according to the link modification parameters in the third message to adapt to the session communication between the UE and the UPF. Based on the direct forwarding identifier, the UPF will send the message information directly to the UE in the subsequent real-time call phase, so as to avoid the message information needing to be forwarded through the ePDG, thereby effectively reducing the transmission latency of message communication in the real-time call phase.
[0065] Figure 9 This is a schematic diagram illustrating the data structure of a direct forwarding identifier, UE address information, port number, and SPI provided in an embodiment of this application. Figure 9 As shown, in the third message, the direct forwarding identifier's information element is `forwardePDGFlg`, and its data type is boolean. Its condition can be adaptively selected as needed in practical applications. This direct forwarding identifier indicates whether the selected UPF supports control plane and media plane separation. Furthermore, the UE's address information's information element is `IP`, and its data type is IPv4 / IPv6 (Internet Protocol version 4 / Internet Protocol version 6). Its condition can be adaptively selected as needed in practical applications. This UE's address information represents its IP address information. The UE's port number's information element is `Port`, and its data type is int. Its condition can be adaptively selected as needed in practical applications. This UE's port number represents its port number information. The UE's SPI's information element is `SPI`, and its data type is int. Its condition can be adaptively selected as needed in practical applications. This UE's SPI represents its SPI information.
[0066] For example, after the SMF sends a third message to the target UPF, the UPF that receives the third message will execute another message forwarding method. Figure 10 This is a flowchart illustrating another message forwarding method provided in an embodiment of this application. This method can be applied to the User Plane Function (UPF) and executed by the UPF. Figure 10 As shown, the method includes steps S310 to S330.
[0067] S310, Receive the third message sent by the Session Management Function (SMF).
[0068] Step S310 will be described in detail below.
[0069] For example, after the SMF sends a third message to the target UPF, the corresponding UPF will receive the third message and then obtain the UE's address information, UE's SPI, direct forwarding identifier, and link modification parameters carried in the third message. Next, it will update and modify the relevant parameters in the UPF's data path according to the link modification parameters to adapt to the session communication between the UE and the UPF.
[0070] After the UPF receives the third message and confirms the update of the relevant parameters of the data path, in order to establish a reliable and secure session communication link between the UE and the UPF, the UPF also needs to perform the following steps S311.
[0071] Step S311: Send the fourth message of the SPI carrying the UPF to the SMF.
[0072] Step S311 will be described in detail below.
[0073] For example, after receiving the third message and confirming, based on the direct forwarding identifier therein, that the UPF needs to establish a reliable and secure session communication link with the UE for direct interaction of message information between the two, and after updating and modifying the relevant parameters in the UPF's data path according to the link modification parameters, the UPF generates a fourth message carrying its own SPI and sends the fourth message (i.e., the PFCP Session Modification Response message) to the SMF to notify the SMF that the link modification parameters in the third message received from the SMF have been successfully applied. Furthermore, the SMF forwards the UPF's SPI to the UE, so that during real-time calls, the UE can use the UPF's SPI as the identifier of the first target message to be sent. Thus, after receiving the first target message, the UPF can clearly identify from the UPF's SPI that the first target message is a secure and reliable message information sent by the UE, thereby improving the reliability and security of the message forwarding method provided in this application.
[0074] After the UPF sends the fourth message to the SMF, in order to establish a reliable and secure session communication link between the UE and the UPF, the SMF also needs to perform the following steps S230 to S240.
[0075] Step S230: Receive the fourth message sent by the target UPF.
[0076] Step S240: Send a sixth message carrying the SPI of the target UPF to the ePDG.
[0077] Steps S230 to S240 are described in detail below.
[0078] For example, after the SMF receives the fourth message carrying the SPI of the target UPF from the target UPF, the SMF confirms from the fourth message that it has successfully applied the link modification parameters from the third message received from the SMF, thereby confirming that the session communication link allocated between the UE and the target UPF has been established. At this time, the SMF generates a sixth message (Create Session Response message) carrying the address information and SPI of the target UPF, and sends the sixth message to the ePDG to confirm to the ePDG that the session communication link allocated between the UE and the target UPF has been established.
[0079] For example, after receiving the sixth message, the ePDG confirms from the sixth message that the session communication link allocated between the UE and the target UPF has been established, and extracts the address information and SPI of the target UPF from the sixth message. Next, the ePDG generates a second message (i.e., an IKE_AUTH Response message) carrying the address information and SPI of the target UPF, and sends the second message to the UE to notify the UE that the session communication link between the UE and the target UPF has been established and that direct real-time communication between the UE and the target UPF can be carried out.
[0080] After the ePDG sends the second message to the UE, such as Figure 5 As shown, the UE will further perform the following step S120 to complete the process of building a session communication link between the UE and the target UPF.
[0081] Step S120: Receive the second message sent by ePDG.
[0082] Step S120 will be described in detail below.
[0083] For example, after the UE receives the second message from the ePDG, the UE will confirm from the second message that the session communication link between the UE and the target UPF has been established, and extract the address information and SPI of the target UPF from the second message.
[0084] The process of establishing a session communication link between the UE and the target UPF is completed through steps S110 and S120 executed by the UE, steps S210, S220, S230, and S240 executed by the target UPF, and steps S310, S320, S330, and S311 executed by the SMF. The direct forwarding identifier generated based on the UE's communication capability identifier is successfully sent to the target UPF. Simultaneously, the UE's address information and SPI are sent to the target UPF, and the target UPF's address information and SPI are sent to the UE. This allows the UE and the target UPF to communicate directly and securely in subsequent real-time session communication without relying on ePDG message forwarding. They can directly utilize each other's address information and SPI for secure and reliable message communication. This effectively reduces communication transmission latency while ensuring secure and reliable communication during the message forwarding method and UPF selection method provided in this application.
[0085] For example, after the session communication link between the UE and the target UPF is established, such as Figure 5 As shown, the UE will further execute steps S130 and S140 to achieve information forwarding of the first target message.
[0086] Step S130: Generate the first target message based on the SPI of the target UPF.
[0087] Step S140: Based on the address information of the target UPF, forward the first target packet directly to the target UPF.
[0088] Steps S130 and S140 are described in detail below.
[0089] For example, after the session communication link between the UE and the target UPF is established, the UE responds to the forwarding of the first target information, generates a first target message based on the information content of the first target information and the SPI of the target UPF, and forwards the first target message directly to the target UPF based on the address information of the target UPF without going through the message information forwarding process of the ePDG, so as to effectively reduce the communication transmission delay in the message communication transmission process.
[0090] For example, when the UE generates the first target message based on the information content of the first target information and the SPI of the target UPF, in order to further improve the security of direct communication between the UE and the UPF, the UE will determine the security association used by the target UPF according to the SPI of the target UPF, encrypt the first target information according to the key and encryption algorithm corresponding to the security association, generate the first target message after encryption, and then forward the first target message directly to the target UPF based on the address information of the target UPF.
[0091] For example, the encryption and decryption algorithms corresponding to the security association can be symmetric encryption algorithms, such as the Advanced Encryption Standard (AES) algorithm; or they can be asymmetric encryption algorithms, such as the Rivest-Shamir-Adleman (RSA) algorithm. This embodiment does not impose excessive restrictions on the encryption and decryption algorithms and keys; different keys and encryption / decryption algorithms can be set according to different scenario needs without affecting the implementation of the solution in this application.
[0092] For example, when the UE executes the address information based on the target UPF and directly forwards the first target packet to the target UPF, it performs the following steps S141 to S142.
[0093] S141. Modify the UE's first message sending address according to the target UPF's address information.
[0094] S142. Based on the modified first message sending address, forward the first target message directly to the target UPF.
[0095] Steps S141 to S142 are described in detail below.
[0096] For example, as described in step S110 above, the UE can support the separation of the control plane and the media plane. Therefore, when sending the first target message, the UE can modify the first message sending address (i.e., the next-hop node address after sending the first target message) of the first target message to the address information of the target UPF according to the address information of the target UPF. Then, based on the modified first message sending address, the first target message is directly forwarded to the target UPF through the established session communication link between the UE and the target UPF.
[0097] For example, after receiving the first target message, the UPF corresponding to the target UPF will verify and decrypt the first target message based on the SPI of the target UPF carried in the first target message. That is, after receiving the first target message, the UPF verifies and matches its own SPI based on the SPI of the target UPF carried in the first target message. Only when the SPI of the target UPF carried in the first target message matches its own SPI is it confirmed that the first target message was directly forwarded to the target UPF by the UE. Next, the target UPF will find the corresponding security association through the SPI and use the key and decryption algorithm corresponding to the security association to decode the information of the first message to obtain the first target information, further improving the security and reliability of the message forwarding process.
[0098] For example, similar to the UE, after the session communication link between the UE and the target UPF is established, such as Figure 10 As shown, the UPF corresponding to the target UPF will further execute steps S320 to S330.
[0099] Step S320: Generate a second target message based on the UE's SPI.
[0100] Step S330: Based on the direct forwarding identifier and the UE's address information, the second target message is directly forwarded to the UE.
[0101] Steps S320 to S330 are described in detail below.
[0102] For example, after the session communication link between the UE and the target UPF is established, the UPF corresponding to the target UPF, in response to the forwarding of the second target information, generates a second target message based on the information content of the second target information and the UE's SPI, and forwards the second target message directly to the UE based on the direct forwarding identifier and the UE's address information, without going through the message information forwarding process of ePDG, so as to effectively reduce the communication transmission delay in the message communication transmission process.
[0103] For example, the second target information can be information directly sent by the target interaction terminal communicating with the UE; or it can be information corresponding to the first target information. That is, after the UPF receives the first target message, it forwards the first target message to the target interaction terminal through IMS, and then the target interaction terminal responds to the first target message and sends feedback information, and sends the feedback information back to the second target information obtained by the UPF through IMS.
[0104] For example, the target interaction end can be various devices or systems that receive data or signals, such as personal computers, mobile devices, servers, network devices, Internet of Things devices, and various embedded systems.
[0105] For example, when the UPF generates the second target message based on the information content of the second target information and the UE's SPI, in order to further improve the security of direct communication between the UE and the UPF, the UPF corresponding to the target UPF will determine the security association used by the UE based on the UE's SPI, and encrypt the second target information according to the key and encryption algorithm corresponding to the security association, and generate the second target message after encryption, and then forward the second target message directly to the UE based on the UE's address information.
[0106] For example, when the UPF forwards the second target message directly to the UE based on the direct forwarding identifier and the UE's address information, it performs the following steps S141 to S142.
[0107] S331. Modify the second message sending address of the UPF according to the direct forwarding identifier and the UE address.
[0108] S332. Based on the modified second message sending address, the second target message is directly forwarded to the UE.
[0109] Steps S331 and S332 are described in detail below.
[0110] For example, as described in step S310 above, the UPF corresponding to the target UPF determined by the direct forwarding identifier can support control plane and media plane separation; and based on the meaning of the direct forwarding identifier, the UPF can determine that the second target message needs to be directly forwarded to the UE. Therefore, when sending the second target message, the UPF can modify the second message sending address (i.e., the next-hop node address after sending the second target message) of the second target message to the UE's address information according to the UE's address information. Then, based on the modified second message sending address, the second target message is directly forwarded to the UE through the established session communication link between the UE and the target UPF.
[0111] For example, after the target UPF directly forwards the second target message to the UE, the UE will further perform the following steps S150 and S160 to receive the second target information in the second target message.
[0112] S150, Receive the second target message directly forwarded by the target UPF.
[0113] S160. Verify and decrypt the second target message using the UE's SPI.
[0114] Steps S150 and S160 are described in detail below.
[0115] For example, after receiving the second target message, the UE will verify and decrypt the second target message based on the UE's SPI carried in the second target message. That is, after receiving the second target message, the UE verifies and matches its own SPI based on the UE's SPI carried in the second target message. Only when the UE's SPI carried in the second target message matches its own SPI is the UE confirmed that the second target message was directly forwarded to the UE by the UPF. Next, the UE will find the corresponding security association through the SPI and use the key and decryption algorithm corresponding to the security association to decode the second message information to obtain the second target information, further improving the security and reliability of the message forwarding process.
[0116] Figure 11 This is a schematic diagram illustrating a message forwarding process provided in an embodiment of this application. For example... Figure 11 As shown, the process includes the following steps.
[0117] In step S1100, the UE sends an IKE_AUTH Request message to the ePDG, carrying a control plane / media plane separation support identifier. This invention requires adding a field to carry a capability identifier, which is used by the ePDG to subsequently determine the UE's capabilities (corresponding to step S110 above).
[0118] In step S1200, ePDG sends a Diameter EAP message to AAA to request authentication.
[0119] In step S1300, AAA sends Diameter EAP_Success to ePDG, indicating that the authentication request was successful.
[0120] In step S1400, the ePDG sends a Create Session Request message to the SMF, carrying the UE's IP address and port number. If the UE supports control plane and media plane separation, it carries the identifier that supports direct forwarding of packets via UPF and the UE's SPI (identifier). This invention requires adding a field to carry the capability identifier and the UE's SPI, which is used by the SMF to determine the UE's capabilities (corresponding to step S210 above).
[0121] In step S1500, after selecting a UPF that supports separation capability, the SMF sends a PFCP SessionModification Request to the UPF, carrying the direct forwarding packet identifier, the UE's IP address, port number, and the UE's SPI. This invention requires adding fields to the message for the content needed for packet forwarding (corresponding to steps S220 and S310 above).
[0122] Step S1600: The UPF sends a PFCP Session Modification Response to the SMF, carrying the UPF's SPI. This invention requires adding a field to the message to carry the UPF's SPI, with the same SPI field type as in Table 3 (corresponding to step S230 above), so that PFCP SessionEstablishment information with the UPF can be established through steps 1500 and 1600.
[0123] In step S1700, the SMF sends a Create Session Response to the ePDG, carrying the address of the UPF and the SPI of the UPF. This invention requires adding a field to the message to carry the SPI of the UPF, with the same type as the SPI field in Table 3 (corresponding to step S240 above).
[0124] In step S1800, the ePDG sends an IKE_AUTH Response message to the UE, carrying the UPF address and SPI. This invention requires adding a field to the message to carry the UPF's SPI, with the same type as the address and SPI fields in Table 3 (corresponding to step S120 above). Through steps S1100 and S1800, the UE and ePDG establish an IKE tunnel via the IKESA_INIT message.
[0125] Step S2000: The UE sends the first target message to the UPF. The destination IP is the address of the UPF and the SPI (corresponding to step S140 above).
[0126] In step S2100, the UPF finds the corresponding bearer based on the SPI and forwards the message.
[0127] In step S2200, the UPF sends a second target message to the UE. The destination address is the UE's IP address and port number, and the SPI is the UE's SPI (corresponding to step S330 above).
[0128] At this point, the message information is directly forwarded between the UE and the UPF.
[0129] For example, when a UE communicates via an AP (Access Point), the AP or a router connected to the AP will assign the UE address information, enabling the UE to communicate or access the Internet within the local area network based on the address information, including the aforementioned message communication.
[0130] When the UE switches from the original AP to a new AP during the process of establishing a session communication link with the target UPF through the above steps and conducting direct message communication with the target UPF, the UE will execute the following steps S170 and S180 to continue message communication.
[0131] S170. In response to the switching of access point AP, determine the new address information of UE based on the new access AP.
[0132] S180, Send an address update message to ePDG.
[0133] Steps S170 to S180 are described in detail below.
[0134] For example, when a UE is engaged in direct message communication with a target UPF, in response to a switch of access point (AP), the UE switches from the original AP to the new access AP and determines the new address information assigned to the UE by the new access AP. Next, to ensure that message communication between the UE and the target UPF continues, the UE will send address update information to the ePDG, specifically an IKE_information request message carrying IKEV2_UPDATE_SA_ADDRESSES (IKEv2 update security association address), to instruct the ePDG to send the UE's new address information to the target UPF.
[0135] For example, after receiving the address update information, the ePDG sends a Modify Bearer Request message to the SMF, carrying the UE's new address information and port number, to notify the SMF that the UE's address information has changed and that the new address information of the UE needs to be sent to the target UPF, and to adaptively modify the relevant parameters of the target UPF's data path.
[0136] For example, after receiving the Modify Bearer Request message, the SMF generates a PFCP Session Modification Request message based on the UE's new address information in the message. The PFCP Session Modification Request message carries the UE's new address information and port number. Then, the SMF sends the PFCP Session Modification Request message to the target UPF to notify the target UPF that the UE's address information has changed.
[0137] For example, after the target UPF sends a PFCP SessionModification Request message carrying the UE's new address information to the target UPF, the UPF corresponding to the target UPF will execute the following steps S340 and S350 to maintain direct message communication with the UE.
[0138] S340: Receive the new address information of the UE sent by the SMF.
[0139] S350: Based on the UE's new address information, the third target message is directly forwarded to the UE.
[0140] Steps S340 to S350 are described in detail below.
[0141] For example, when the UPF corresponding to the target UPF receives a PFCP Session Modification Request message from the SMF carrying the UE's new address information and port number, it will obtain the UE's new address information and port number from the message and adaptively modify the relevant parameters of the target UPF's data path according to the PFCP Session Modification Request message. Then, the UPF sends a PFCP Session Modification Response message to the SMF to notify the SMF that the changed parameters in the PFCP Session Modification Request message received from the SMF have been successfully applied.
[0142] After receiving the PFCP Session Modification Request information from the UPF corresponding to the target UPF, the SMF sends a Modify Bearer Response message to the ePDG to confirm that the target UPF has adaptively modified the relevant parameters of the target UPF's data path.
[0143] Next, based on the UE's new address information, the target UPF, similar to step 330 above, directly forwards the third target message to the UE and receives the first target message sent by the UE's new address information, thereby ensuring the reliability and stability of the direct message forwarding communication between the UE and the target UPF. It can be understood that the third target message, like the second target message, is a directly forwarded message sent by the target UPF to the UE.
[0144] Figure 12 This is a flowchart illustrating a UE's message forwarding response to AP handover, provided in an embodiment of this application. Figure 12 As shown, the UE communicates via AP1 (such as...) Figure 11 During the process of communicating with the target UPF (as shown in the diagram), the relevant procedures in response to switching to AP2 include the following steps.
[0145] S3100 and UE directly forward the first target message to UPF through AP1. The first message sending address of the first target message is the address information of UPF, and the SPI is the SPI of UPF.
[0146] S3200, UPF and IMS exchange target messages.
[0147] S3300 and UPF send a second target message through AP1, wherein the second message sending address of the second target message is the UE's address information and the SPI is the UE's SPI.
[0148] S3400 and AP1 send a second target message to the UE.
[0149] Then the terminal moves to AP2 and initiates the access point switching process.
[0150] S4100: The UE sends an IKE_information Request message to the ePDG, carrying IKEV2_UPDATE_SA_ADDRESSES, instructing the ePDG to send the UE's new address information to the UPF.
[0151] The S4200 and ePDG send an IKE_information Response message to the UE.
[0152] The S4300 and ePDG send a Modify Bearer Request to the SMF, carrying the new address information and port number of the new UE.
[0153] S4400 and SMF send a PFCP Session Modification Request to UPF, carrying the new address information and port number of the new UE.
[0154] S4500 and UPF send PFCP Session Modification Response to SMF.
[0155] S4600 and SMF send Modify Bearer Response to EPDG.
[0156] S5000 and UE send a first target message to AP2, wherein the first message sending address of the first target message is the address information of UPF and the SPI is the SPI of UPF.
[0157] S5100 and AP2 forward the first destination message to UPF.
[0158] S5200, UPF and IMS exchange target messages.
[0159] S5300 and UPF send a second target message to AP2, wherein the second message sending address of the second target message is the new address information of the UE, and the SPI is the UE's SPI.
[0160] S5400 and AP2 send a second target message to the UE.
[0161] Thus, during the direct message communication between the UE and the UPF, after the AP handover process, the UE sends its new address information to the target UPF via ePDG and SMF, and notifies the target UPF to update the relevant parameters of the communication session link between the UE and the target UPF. This ensures direct message communication between the UE and the target UPF, thereby reducing the transmission latency during the message communication process and improving the reliability of the message forwarding method provided in this application.
[0162] This application embodiment leverages the feature that UEs and UPFs supporting control plane and media plane separation can modify the address information of the next node in the message information. During the construction of the communication session link between the UE and the UPF, the ePDG sends an identifier indicating that the UE supports control plane and media plane separation to the SMF. This allows the SMF to select a target UPF that also supports control plane and media plane separation, and sends the UE's address information and SPI to the target UPF, as well as the target UPF's address information and SPI to the UE. After establishing the communication session link between the UE and the target UPF, the UE can directly forward the first target message to the target UPF based on the UPF's address information and SPI, and the target UPF will then forward it to the target interaction terminal of the first target message. Simultaneously, the target UPF can directly forward the second target message to the UE based on the UE's address information and SPI. Therefore, during the real-time message session transmission of the first and second target messages, there is no need for forwarding through the ePDG, avoiding performance issues caused by message information transmission delays due to limitations of the ePDG device itself, and effectively reducing transmission latency during message transmission.
[0163] This application also provides an electronic device, such as... Figure 13 As shown, the electronic device 1300 includes: One or more processors 1310; The memory 1320 stores one or more programs, which, when executed by one or more processors 1310, enable the one or more processors 1310 to implement the message forwarding method provided in any embodiment of this application.
[0164] Memory 1320, as a non-transitory network system, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory 1320 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory 1320 may optionally include remotely located memories 1320 relative to processor 1310, which can be connected to processor 1310 via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.
[0165] The memory 1320 can be implemented as a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 1320 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 1320 and is called and executed by the processor 1310 using the message forwarding method of the embodiments of this application.
[0166] The processor 1310 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application.
[0167] In some embodiments, the electronic device further includes: Input / output interfaces are used to implement information input and output; The communication interface is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). The bus transmits information between various components of the device (e.g., processor 1310, memory 1320, input / output interfaces, and communication interfaces); The processor 1310, memory 1320, input / output interface, and communication interface can communicate with each other within the device via a bus.
[0168] An embodiment of this application also provides a computer-readable storage medium storing computer-executable instructions for executing a message forwarding method provided in any embodiment of this application.
[0169] An embodiment of this application also provides a computer program product, including a computer program or computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer program or computer instructions from the computer-readable storage medium and executes the computer program or computer instructions, causing the computer device to perform a message forwarding method that implements any embodiment of this application.
[0170] The system architecture and application scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. Those skilled in the art will know that as the system architecture evolves and new application scenarios emerge, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.
[0171] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.
[0172] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.
[0173] It should be understood that in the description of the embodiments of this application, the use of terms such as "first" and "second" is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features indicated, or implicitly indicating the order of the technical features indicated. "At least one" means one or more, and "more" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can indicate the existence of A alone, the simultaneous existence of A and B, or the existence of B alone. A and B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship. "At least one of the following" and similar expressions refer to any group of these items, including any group of singular or plural items. For example, at least one of a, b, and c can mean: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.
[0174] Furthermore, the technical features involved in the various embodiments described in this application can be combined with each other as long as they do not conflict with each other.
[0175] The above description, with reference to the accompanying drawings, illustrates some embodiments of this application, but does not limit the scope of the invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and spirit of this invention should be considered within the scope of this application.
Claims
1. A message forwarding method, characterized in that, The method is applied to a user equipment (UE), and the method includes: Send a first message to the evolved packet data gateway (ePDG), the first message carrying the communication capability identifier of the UE, the communication capability identifier being used to characterize that the UE supports control plane and media plane separation; Receive a second message sent by the ePDG, the second message carrying the address information and security parameter index SPI corresponding to the target user plane function UPF, the target UPF supporting control plane and media plane separation; Generate a first target message based on the SPI of the target UPF; Based on the address information of the target UPF, the first target packet is directly forwarded to the target UPF.
2. The message forwarding method according to claim 1, characterized in that, The step of directly forwarding the first target packet to the target UPF based on the address information of the target UPF includes: Modify the first message sending address of the UE according to the address information of the target UPF; Based on the modified first message sending address, the first target message is directly forwarded to the target UPF.
3. The message forwarding method according to claim 1, characterized in that, After forwarding the first target message directly to the target UPF, the method further includes: Receive the second target message directly forwarded by the target UPF, the second target message carrying the UE's SPI; The second target message is verified and decrypted using the UE's SPI.
4. The message forwarding method according to claim 1, characterized in that, After forwarding the target message directly to the target UPF, the method further includes: In response to switching access points (APs), the new address information of the UE is determined based on the new access AP; An address update message is sent to the ePDG, which instructs the ePDG to send the new address information of the UE to the target UPF.
5. A message forwarding method, characterized in that, The method is applied to a UPF, and the method includes: The UE receives a third message sent by the Session Management Function (SMF). The third message carries the UE's address information, SPI, and direct forwarding identifier. The direct forwarding identifier is generated based on the UE's communication capability identifier, which indicates that the UE supports control plane and media plane separation. Generate a second target message based on the UE's SPI; Based on the direct forwarding identifier and the UE's address information, the second target message is directly forwarded to the UE.
6. The message forwarding method according to claim 5, characterized in that, After receiving the third message sent by the Session Management Function (SMF), the method further includes: Send a fourth message carrying the SPI of the UPF to the SMF.
7. The message forwarding method according to claim 5, characterized in that, The step of directly forwarding the second target packet to the UE based on the direct forwarding identifier and the UE's address information includes: Modify the second message sending address of the UPF according to the direct forwarding identifier and the UE address; Based on the modified second message sending address, the second target message is directly forwarded to the UE.
8. The message forwarding method according to claim 5, characterized in that, After forwarding the second target message directly to the UE, the method further includes: The system receives the new address information of the UE sent by the SMF, wherein the new address information of the UE is obtained by the UE in response to the handover of the access point (AP); Based on the UE's new address information, the third target message is directly forwarded to the UE.
9. A method for selecting UPF, characterized in that, The method is applied to SMF, and the method includes: The system receives a fifth message sent by the ePDG, which carries the UE's address information and a direct forwarding identifier. The direct forwarding identifier is generated based on the UE's communication capability identifier, which indicates that the UE supports control plane and media plane separation. The target UPF that supports control plane and media plane separation is determined based on the direct forwarding identifier, and a third message is sent to the target UPF. The third message carries the UE's address information, SPI, and direct forwarding identifier. The UE's SPI is used to generate a second target message, and the direct forwarding identifier is used to instruct the target UPF to directly forward the second target message to the UE based on the UE's address information.
10. The method for selecting UPF according to claim 9, characterized in that, After determining the target UPF that supports control plane and media plane separation based on the direct forwarding identifier, and sending a third message to the target UPF, the method further includes: Receive a fourth message sent by the target UPF, the fourth message including the SPI of the target UPF; Send a sixth message to the ePDG carrying the SPI of the target UPF.
11. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the message forwarding method according to any one of claims 1 to 4, or the message forwarding method according to any one of claims 5 to 8, or the UPF selection method according to any one of claims 9 to 10.
12. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the message forwarding method according to any one of claims 1 to 4, or the message forwarding method according to any one of claims 5 to 8, or the UPF selection method according to any one of claims 9 to 10.