Communication method, communication device and communication system

Abstract

The invention provides a communication method, a communication device and a communication system, and relates to the technical field of communication. The communication method is applied to a control plane network element, and comprises the following steps: receiving an IP type session establishment request message initiated by a terminal; obtaining subscription information of the VN group corresponding to the terminal and including the identifier of the VN group; creating a group session corresponding to the VN group; sending a layer 2 forwarding identifier and an identifier of the VN group to the user plane network element, wherein the layer 2 forwarding identifier is used for triggering the user plane network element to perform layer 2 forwarding on the Ethernet message received under the session; and sending a session establishment response message comprising a layer 2 forwarding identifier to the terminal, wherein the layer 2 forwarding identifier is used for triggering the terminal to process a message received through the session according to an Ethernet message, or packaging data to be sent through the session into the Ethernet message and then sending the Ethernet message. According to the embodiment of the invention, the terminal is helped to access the VN group in an IP type session mode and carry out layer-2 message transmission with other terminals in the VN group.

Description

Technical Field

[0001] This application relates to the field of communication technology, specifically to a communication method, communication device, and communication system. Background Technology

[0002] A 5G local area network (LAN) is a network formed by grouping terminal users into groups using 5G technology within a 5G mobile communication network. The 3GPP standard defines 5G LAN as supporting two transmission modes: data link layer (Layer 2, L2) and network layer (Layer 3, L3). L2 mode refers to Ethernet packets transmitted to terminals in the 5G network, without requiring the allocation of an Internet Protocol (IP) address. L3 mode refers to IP packets transmitted in the 5G network, requiring the allocation of an IP address to the terminal. Currently, 5G LAN can only be used in a 5G network environment; L2 forwarding of 5G LAN virtual network groups cannot be implemented in 4G networks, which is detrimental to the expansion of 5G LAN services. Summary of the Invention

[0003] This application provides a communication method, communication device, and communication system, which facilitates the transmission of Ethernet packets by a terminal when accessing a virtual network group under an IP-type session. The various aspects involved in the embodiments of this application are described below.

[0004] Firstly, a communication method is provided, applied to a control plane network element, which can be a control plane network element in the core network of a 4G, 5G, 6G, or future communication network. The communication method includes: receiving a session establishment request message from a terminal, wherein the session is an Internet Protocol (IP) type session; obtaining subscription information of a Virtual Network (VN) group corresponding to the terminal, wherein the subscription information of the VN group includes an identifier of the VN group; creating a group session corresponding to the VN group based on the subscription information of the VN group; sending a Layer 2 forwarding identifier and the identifier of the VN group to a user plane network element, wherein the Layer 2 forwarding identifier is used to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets received through the session, and the identifier of the VN group is used to indicate that the session is a session within the VN group; and sending a session establishment response message to the terminal, wherein the session establishment response message includes the Layer 2 forwarding identifier, wherein the Layer 2 forwarding identifier is used to trigger the terminal to process packets received through the session as Ethernet packets, or to encapsulate data to be sent through the session into Ethernet packets before sending.

[0005] In this embodiment, the control plane network element obtains the subscription information of the VN group corresponding to the terminal, and creates a group session corresponding to the VN group based on the subscription information. It sends a Layer 2 forwarding identifier and the VN group identifier to the user plane network element to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets received under the IP type session. It also sends a session establishment response message including the Layer 2 forwarding identifier to the terminal to trigger the terminal to process packets received through the session as Ethernet packets, or to encapsulate data to be sent through the session into Ethernet packets before sending. This embodiment facilitates the terminal's access to the VN group using an IP type session and enables Layer 2 packet transmission with other terminals within the 5G VN group.

[0006] In some possible implementations, the session establishment request message includes the feature identifier of the terminal, and the step of creating a group session corresponding to the VN group based on the subscription information of the VN group includes: if it is determined that the feature identifier of the terminal matches the feature identifier in a preset identifier set, creating a group session corresponding to the VN group based on the subscription information of the VN group, wherein the terminal corresponding to any feature identifier in the preset identifier set supports the transmission of Ethernet packets under IP type session.

[0007] After identifying that the terminal supports the transmission of Ethernet packets under IP type sessions, the group session corresponding to the VN group is created. For terminals that do not support the transmission of Ethernet packets under IP type sessions, this helps to avoid the control plane network element sending invalid group session creation request signaling to the user plane network element, reducing the amount of data exchanged in signaling.

[0008] In some possible implementations, creating a group session corresponding to the VN group based on the subscription information of the VN group includes: sending a Packet Forwarding Control Protocol (PFCP) group session establishment request to the user plane network element, the group session establishment request including the identifier of the VN group; receiving a PFCP group session establishment response, the group session establishment response including the IP information of the Virtual Extended LAN Tunnel Endpoint (VTEP) of the user plane network element and the Virtual Extended LAN Identifier (VNI) corresponding to the terminal, the IP information of the VTEP of the user plane network element and the VNI being used to configure the tunnel of the VN group, the tunnel of the VN group being used by the user plane network element and the terminal to transmit encapsulated Ethernet packets.

[0009] The creation of a group session corresponding to a VN group and the specific interaction steps between control plane network elements and user plane network elements are clarified. The group session establishment response includes the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal. This parameter is used by the user plane network element to configure the tunnel of the VN group so that subsequent transmission of user plane Ethernet packets can be carried out based on this tunnel.

[0010] In some possible implementations, sending the Layer 2 forwarding identifier and the identifier of the VN group to the user plane network element includes: sending a Packet Forwarding Control Protocol (PFCP) user session establishment request to the user plane network element, wherein the PFCP user session establishment request includes the Layer 2 forwarding identifier and the identifier of the VN group, and the PFCP user session is associated with the group session; and receiving a PFCP user session establishment response.

[0011] The specific interaction steps between control plane network elements and user plane network elements for creating a PFCP user session are clarified. The PFCP user session establishment request includes a Layer 2 forwarding identifier and a VN group identifier to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets under IP type sessions.

[0012] In some possible implementations, the session establishment response message further includes: the IP information of the Virtual Extended LAN Tunnel Endpoint (VTEP) of the user plane network element and the Virtual Extended LAN Identifier (VNI) corresponding to the terminal. The IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the VN group. The tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

[0013] The session establishment response message sent to the terminal includes the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal. It is used to configure the tunnel of the VN group on the terminal side so that Ethernet packets can be transmitted based on the tunnel in the future.

[0014] In some possible implementations, obtaining the subscription information of the VN group corresponding to the terminal includes: obtaining the identifier of the shared VN group data corresponding to the terminal; and obtaining the subscription information of the VN group corresponding to the terminal based on the identifier of the shared VN group data.

[0015] First, obtain the identifier of the shared VN group data, and then obtain the VN group's contract information based on the identifier of the shared VN group data.

[0016] In some possible implementations, obtaining the subscription information of the VN group corresponding to the terminal includes: obtaining the subscription information of the VN group corresponding to the terminal from the Unified Data Management (UDM) network element.

[0017] The VN group's contract information is stored in the UDM network element, and the VN group's contract information can be obtained from the UDM network element.

[0018] In some possible implementations, the session establishment request message includes the feature identifier of the terminal, and obtaining the subscription information of the user corresponding to the terminal includes: if it is determined that the feature identifier of the terminal matches the feature identifier in a preset identifier set, obtaining the identifier of the shared VN group data corresponding to the terminal, wherein the terminal corresponding to any feature identifier in the preset identifier set supports the transmission of Ethernet packets under IP type session.

[0019] After identifying that the terminal supports the transmission of Ethernet packets under IP type sessions, the identifier of the corresponding shared VN group data for the terminal is obtained. For terminals that do not support the transmission of Ethernet packets under IP type sessions, this helps to avoid control plane network elements sending invalid request signaling and reduces the amount of data exchanged in signaling.

[0020] In some possible implementations, obtaining the identifier of the shared VN group data corresponding to the terminal includes: sending a subscription information request message to the UDM network element to request the subscription information of the user corresponding to the terminal; and receiving the subscription information of the user from the UDM network element, wherein the user's subscription information includes the identifier of the shared VN group data corresponding to the terminal.

[0021] The specific interaction steps for control plane network elements to obtain identifiers for shared VN group data from UDM network elements were clarified.

[0022] In some possible implementations, obtaining the subscription information of the VN group from the UDM network element includes: sending a request message for VN group subscription information, the request message for VN group subscription information including an identifier of the shared VN group data; and receiving the subscription information of the VN group from the UDM network element.

[0023] The specific interaction steps for control plane network elements to obtain VN group subscription information from UDM network elements based on the identifier of shared VN group data are clarified.

[0024] In some possible implementations, obtaining the subscription information of the VN group corresponding to the terminal includes: obtaining the subscription information of the VN group from the Authentication, Authorization and Accounting (AAA) network element.

[0025] The VN group's contract information is stored in the AAA network element, and this contract information can be retrieved from the AAA network element.

[0026] In some possible implementations, the session establishment request message includes the feature identifier of the terminal, and obtaining the subscription information of the VN group from the AAA network element includes: obtaining the user's subscription information from the AAA network element based on the feature identifier corresponding to the terminal, wherein the user's subscription information includes the subscription information of the VN group.

[0027] The feature identifier can be, for example, a permanent user identifier (SUPI). In some possible implementations, obtaining the subscription information of the VN group from the AAA network element may include: obtaining the user's subscription information from the AAA network element based on the permanent user identifier corresponding to the terminal, wherein the user's subscription information includes the subscription information of the VN group.

[0028] In some possible implementations, obtaining the subscription information of the VN group from the AAA network element includes: sending a request message for VN group subscription information, the request message for VN group subscription information including a permanent user identifier and an access point name; and receiving subscription information of a user from the AAA network element, the user's subscription information including the subscription information of the VN group.

[0029] The specific interaction steps for control plane network elements to obtain VN group subscription information from AAA network elements based on permanent user identifier name and access point name are clarified.

[0030] In some possible implementations, the feature identifier includes at least one of the following: Data Network Name (DNN), General Public User Identifier (GPSI), or Permanent User Identifier (SUPI). This clarifies the specific type of feature identifier representing the terminal.

[0031] In some possible implementations, the control plane network element is a Packet Data Network Gateway Control Plane PGW-C network element, and the user plane network element is a Packet Data Network Gateway User Plane PGW-U network element; or, the control plane network element is a Session Management Function (SMF) network element, and the user plane network element is a User Plane Function (UPF) network element. The specific forms of the control plane network element and the user plane network element are thus clarified.

[0032] Secondly, a communication method is provided for use in a terminal. This terminal can be a terminal itself, or a chip within the terminal (such as a modem chip, also known as a baseband chip, or a system-on-a-chip (SoC) chip containing a modem core, or a system-in-package (SIP) chip), or a logical node, logical module, or software capable of implementing all or part of the terminal's functions. The communication method includes: sending a session establishment request message, wherein the session is an Internet Protocol (IP) type session; receiving the session establishment response message, wherein the session establishment response message includes a Layer 2 forwarding identifier; and, based on the Layer 2 forwarding identifier, the terminal processes packets received through the session as Ethernet packets, or encapsulates data to be sent through the session into Ethernet packets before sending them.

[0033] The session establishment response message received by the terminal includes a Layer 2 forwarding identifier. Based on the Layer 2 forwarding identifier, the terminal initiates the function of transmitting Ethernet packets under IP type session, and can transmit Ethernet packets with user plane network elements under IP type session.

[0034] In some possible implementations, the session establishment response message further includes: the IP information of the Virtual Extended LAN Tunnel Endpoint (VTEP) of the user plane network element and the Virtual Extended LAN Identifier (VNI) corresponding to the terminal. The IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the Virtual Network (VN) group to which the terminal belongs. The tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

[0035] The session establishment response message received by the terminal includes the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal. It is used to configure the tunnel of the VN group on the terminal side so that Ethernet packets can be transmitted based on the tunnel in the future.

[0036] In some possible implementations, the terminal encapsulates the data to be sent through the session into Ethernet packets before sending it, or processes the packets received through the session as Ethernet packets, including: the terminal encapsulates the data to be sent through the session into Ethernet packets and sends Ethernet packets encapsulated based on the Packet Data Convergence Protocol (PDCP); or, the terminal decapsulates the packets received through the session based on PDCP, wherein the received packets are information from the Virtual Network (VN) group to which the terminal belongs.

[0037] The terminal encapsulates Ethernet packets based on the PDCP protocol and sends them. It transmits Ethernet packets based on the GTPU tunnel so that user plane network elements can perform Layer 2 forwarding of Ethernet packets received through IP type sessions based on GTPU. This reduces the number of encapsulation and decapsulation operations on Ethernet packets and the amount of auxiliary data transmitted.

[0038] In some possible implementations, the terminal encapsulates the data to be sent through the session into Ethernet packets before sending it, or processes the packets received through the session as Ethernet packets in the user plane network element, including: the terminal encapsulates the data to be sent through the session into Ethernet packets and sends the Ethernet packets encapsulated based on a first communication protocol; or, the terminal decapsulates the packets received through the session based on the first communication protocol, wherein the received packets are information from the virtual network (VN) group to which the terminal belongs; the first communication protocol includes: L3 network protocol, Virtual Extended Local Area Network (VXLAN) protocol, and Packet Data Convergence Protocol (PDCP).

[0039] The terminal encapsulates Ethernet packets based on the first communication protocol and sends them. During the packet transmission process, if the intermediate network element checks and confirms that the packet transmission meets the requirements of the IP type session, the success rate of normal communication is guaranteed.

[0040] Thirdly, a communication method is provided for use in a terminal. The description of the terminal can be found in the second aspect. The communication method includes: sending a session establishment request message, wherein the session is an Internet Protocol (IP) type session; receiving a session establishment response message; and, based on a pre-configured Layer 2 forwarding identifier, the terminal encapsulates data to be sent through the session into Ethernet packets before sending it, or processes packets received through the session as Ethernet packets.

[0041] Based on a pre-configured Layer 2 forwarding identifier, the terminal can transmit Ethernet packets with user plane network elements in IP-type sessions. This helps reduce the configuration of Layer 2 forwarding identifiers in the session establishment response information sent by control plane network elements, thus reducing the data volume of the session establishment response information.

[0042] The third aspect provides some possible implementation methods and beneficial effects, which can be referred to in the second aspect and will not be elaborated further.

[0043] In some possible implementations, based on a pre-configured Layer 2 forwarding identifier, the IP information of the Virtual Extended LAN Tunnel Endpoint (VTEP) of the user plane network element, and the Virtual Extended LAN Identifier (VNI) corresponding to the terminal, the terminal encapsulates the data to be sent through the session into Ethernet packets before sending it, or processes the packets received through the session as Ethernet packets; the IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the Virtual Network (VN) group to which the terminal belongs, and the tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

[0044] The terminal configures the VN group tunnel based on the pre-configured IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal, so that Ethernet packets can be transmitted based on the VN group tunnel in the future.

[0045] Fourthly, a communication device is provided, which is a control plane network element. The communication device includes modules / units corresponding to each of the methods / operations / steps / actions described in the first aspect or any possible implementation thereof. These modules / units can be hardware circuits, software, or a combination of hardware circuits and software implementation.

[0046] Fifthly, a communication device is provided, which is a terminal. The description of the terminal can refer to the second aspect, and it can also be a logic module or software capable of implementing all or part of a terminal.

[0047] The communication device includes modules / units that perform the methods / operations / steps / actions described in the second aspect or any possible implementation of the second aspect, or the third aspect or any possible implementation of the third aspect. The modules / units can be hardware circuits, software, or a combination of hardware circuits and software.

[0048] Sixthly, a communication device is provided, which can be a control plane network element or a terminal. The description of the terminal is as described in the second aspect and will not be repeated here.

[0049] The communication device includes a processor and a memory, the processor being coupled to the memory, the memory being used to store a program (also referred to as code or instructions), the program being executed by the processor to cause the device to perform a method in either or any possible implementation thereof.

[0050] In some possible implementations, the communication device also includes a memory coupled to the processor.

[0051] In some possible implementations, there are one or more processors, and / or one or more memories.

[0052] In some possible implementations, the memory can be integrated with the processor, or the memory can be set up separately from the processor.

[0053] In a seventh aspect, a processing apparatus is provided, comprising a processor and an input / output interface, for example, applied in a communication device, for implementing the functions or methods involved in any of the preceding aspects, the processing apparatus being, for example, a chip system.

[0054] In one feasible implementation, the chip system further includes a memory for storing program instructions and data necessary to implement the functions of the methods described in any of the above aspects. The chip system in the above aspects can be a System-on-a-Chip (SoC) or a baseband chip, etc., wherein the baseband chip can include a processor, channel encoder, digital signal processor, modem, and interface module, etc.

[0055] In specific implementation, the input signal received by the input interface can be received and input by, for example, but not limited to, a receiver, and the signal output by the output interface can be output to, for example, but not limited to, a transmitter and transmitted by the transmitter. Furthermore, the input interface and output interface can be integrated into a single interface, which is used as both an input interface and an output interface at different times. This application does not limit the specific implementation methods of the processor and various interfaces.

[0056] Eighthly, a communication system is provided, which includes control plane network elements and user plane network elements.

[0057] A control plane network element is configured to receive a session establishment request message from a terminal, wherein the session is an Internet Protocol (IP) session; obtain the subscription information of the VN group corresponding to the terminal, wherein the subscription information of the VN group includes the identifier of the VN group; create a group session corresponding to the VN group based on the subscription information of the VN group; send a Layer 2 forwarding identifier and the identifier of the VN group to a user plane network element, wherein the Layer 2 forwarding identifier is used to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets received through the session, and the identifier of the VN group is used to indicate that the session is a session in the VN group; send a session establishment response message to the terminal, wherein the session establishment response message includes the Layer 2 forwarding identifier, wherein the Layer 2 forwarding identifier is used to trigger the terminal to process packets received through the session as Ethernet packets, or to encapsulate data to be sent through the session into Ethernet packets before sending; and the user plane network element is configured to receive the Layer 2 forwarding identifier and perform Layer 2 forwarding of Ethernet packets received through the session based on the Layer 2 forwarding identifier.

[0058] In this embodiment, the control plane network element obtains the subscription information of the VN group corresponding to the terminal, and creates a group session corresponding to the VN group based on the subscription information. It sends a Layer 2 forwarding identifier and the VN group identifier to the user plane network element to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets received under the IP type session. It also sends a session establishment response message including the Layer 2 forwarding identifier to the terminal to trigger the terminal to process packets received through the session as Ethernet packets, or to encapsulate data to be sent through the session into Ethernet packets before sending. This embodiment facilitates the terminal's access to the VN group using an IP type session and enables Layer 2 packet transmission with other terminals within the 5G VN group.

[0059] The eighth aspect provides some possible implementation methods and beneficial effects that can be referred to the first aspect, and will not be elaborated further.

[0060] In some possible implementations, the user plane network element is used to perform Layer 2 forwarding of Ethernet packets received through the session according to the Layer 2 forwarding identifier, including: decapsulating the Ethernet packets received through the session based on the General Packet Radio Service Tunneling Protocol User Plane (GTPU) according to the Layer 2 forwarding identifier, obtaining the initial Ethernet packet and the destination Media Access Control (MAC) address, encapsulating the initial Ethernet packet based on GTPU, and forwarding it according to the destination MAC address, wherein the destination MAC address is used to indicate the Layer 2 address of the peer of the terminal, and the received Ethernet packet is information from the VN group to which the terminal belongs.

[0061] User plane network elements perform Layer 2 forwarding of Ethernet packets received through IP type sessions based on GTPU, with fewer encapsulation and decapsulation operations on Ethernet packets and less auxiliary data transmission.

[0062] In some possible implementations, the user plane network element, used to perform Layer 2 forwarding of Ethernet packets received through the session according to the Layer 2 forwarding identifier, includes: decapsulating the Ethernet packets received through the session based on the Layer 2 forwarding identifier and a second communication protocol to obtain the initial Ethernet packet and the destination MAC address; encapsulating the initial Ethernet packet based on the second communication protocol and forwarding it according to the destination MAC address; the destination MAC address is used to indicate the Layer 2 address of the peer of the terminal; the received Ethernet packet is information from the VN group to which the terminal belongs; the second communication protocol includes: Network Layer 3 network protocol, Virtual Extended Local Area Network (VXLAN) protocol, and General Packet Radio Service Tunneling Protocol User Plane (GTPU).

[0063] User plane network elements perform Layer 2 forwarding of Ethernet packets received through IP type sessions based on the second communication protocol. During packet transmission, if intermediate network elements check that the packet transmission requirements under IP type sessions are met, normal communication is guaranteed.

[0064] In a ninth aspect, a communication system is provided, the communication system including communication means (such as control plane network element, terminal device) for performing any aspect of the method.

[0065] In a tenth aspect, a readable storage medium (also referred to as a computer-readable storage medium) is provided, on which a program (also referred to as code, instructions, or a computer program) is stored, which, when the program is run on a device, causes the device to perform the method in any of the foregoing aspects or any possible implementations of any of the foregoing aspects.

[0066] Eleventhly, a program product is provided, comprising: a program (also referred to as code or instructions) that, when run on a device, causes the device to perform the methods of any of the above aspects or any possible implementations of any of the above aspects.

[0067] In a twelfth aspect, a chip is provided, comprising: a processor and a memory, the memory for storing a program (also referred to as code or instructions), the processor for calling and running the program stored in the memory, such that an apparatus or device on which the chip is mounted performs the method of any of the above aspects or any possible implementation thereof. Attached Figure Description

[0068] Figure 1 This is a schematic diagram of a communication system applicable to this application.

[0069] Figure 2 This is a schematic block diagram of a 5G network architecture applicable to this application.

[0070] Figure 3 This is a schematic block diagram of a 4G / 5G network architecture applicable to this application.

[0071] Figure 4 This is a schematic flowchart of a communication method provided in an embodiment of this application.

[0072] Figure 5 yes Figure 4 The flowchart illustrates one possible implementation of the method shown.

[0073] Figure 6 yes Figure 4 The diagram illustrates one possible message encapsulation method for the shown approach.

[0074] Figure 7 yes Figure 4 A schematic diagram of another possible message encapsulation method shown.

[0075] Figure 8 This is a schematic flowchart of a communication method provided in another embodiment of this application.

[0076] Figure 9 yes Figure 4 A flowchart illustrating another possible implementation of the method shown.

[0077] Figure 10 yes Figure 8 The flowchart illustrates one possible implementation of the method shown.

[0078] Figure 11 This is a schematic diagram of a communication device provided in an embodiment of this application.

[0079] Figure 12 This is a schematic structural diagram of a communication device provided in another embodiment of this application.

[0080] Figure 13 This is a schematic diagram of a communication system provided in an embodiment of this application. Detailed Implementation

[0081] The technical solutions of the embodiments of this application will now be described with reference to the accompanying drawings. To facilitate understanding of the embodiments of this application, the application scenarios involved in the embodiments of this application will be introduced first.

[0082] Communication system The technical solutions of this application can be applied to various communication systems, such as: 4th generation (4G) systems, 5th generation (5G) systems, new radio (NR), long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, global system of mobile communication (GSM) systems, general packet radio service (GPRS), universal mobile telecommunication system (UMTS), etc. The methods provided in this application can also be applied to non-terrestrial network (NTN) communication systems, or scenarios where NTN and terrestrial network (TN) are integrated. The NTN system can be an NTN system integrated with 4G, 5G, and any future generation of communication systems, such as NR NTN, Internet of Things (IoT) NTN, etc. NTN communication systems can be, for example, satellite communication systems, or include unmanned aerial vehicles (UAVs), high-altitude platform stations (HAPS), and other airborne access network equipment; this application does not limit this. The technical solutions provided in this application can also be applied to future evolving communication systems.

[0083] To facilitate understanding of the embodiments of this application, firstly, in conjunction with Figure 1 This describes a communication system applicable to embodiments of this application. For example... Figure 1 As shown, the communication system 100 may include a radio access network (RAN) 110, a core network (CN) 120, the Internet 130, and at least one terminal 112 (such as...). Figure 1 112a-112j in the above are collectively referred to as 112. The wireless access network 110 may include at least one access network device (such as...). Figure 1 111a and 111b in the diagram are collectively referred to as 111, or RAN nodes. The radio access network 110 may also include other RAN nodes, such as wireless relay devices and / or wireless backhaul devices. Figure 1(Not shown in the image). Terminal 112 is connected to access network device 111 wirelessly. Access network device 111 is connected to core network 120 wirelessly or via wired connection. The core network device in core network 120 and access network device 111 in wireless access network 110 can be different physical devices, or they can be the same physical device integrating core network logical functions and wireless access network logical functions.

[0084] The radio access network 110 can be a cellular system related to the 3rd generation partnership project (3GPP). For example, 4G, 5G mobile communication systems, non-terrestrial network (NTN) systems, or future-oriented evolution systems (such as 6G mobile communication systems). The radio access network 110 can also be an open RAN (open RAN, O-RAN, or ORAN), a cloud radio access network (CRAN), or a wireless fidelity (WiFi) system, or a communication system integrating two or more of the above systems.

[0085] The term "terminal" in this application embodiment can also refer to a terminal device, which may include user equipment (UE), station, access terminal, user unit, user station, mobile station, mobile station (MS), remote station, remote terminal, mobile terminal (MT), user terminal, terminal device, wireless communication equipment, user agent, or user device, or a device used to provide voice or data connectivity to users, or an Internet of Things (IoT) device. For example, a terminal includes handheld devices with wireless connectivity, vehicle-mounted devices, etc., which are not limited in this application embodiment. For example, a terminal can also be a communication module with satellite communication capabilities, a satellite phone or its components, or a satellite communication terminal, such as a very small aperture terminal (VSAT), portable station, fixed station, vehicle-mounted or airborne satellite communication terminal, etc. It should be understood that a satellite communication terminal can serve as a micro base station to further provide a data interface to the accessed user equipment.

[0086] The terminal in this application embodiment may be a mobile phone, cellular phone, cordless phone, session initiation protocol (SIP) phone, wireless local loop (WLL) station, personal digital assistant (PDA), handheld device with wireless communication function, computing device or other processing device connected to a wireless modem, large screen, vehicle-mounted device (e.g., car, bicycle, electric vehicle, airplane, ship, train, high-speed rail, etc.), wearable device (e.g., smartwatch, smart bracelet, pedometer, smart glasses, etc.), machine type communication (MTC) terminal, terminal in 5G network, or terminal in future evolved public land mobile network (PLMN), etc., and is not limited to this in this application embodiment. The terminal in this application embodiment can also be a tablet computer, laptop computer, handheld computer, mobile internet device (MID), virtual reality (VR) device, augmented reality (AR) device, point of sale (POS) machine, customer-premises equipment (CPE), light UE, reduced capability UE (RedCap UE), wireless terminal in industrial control, smart home device (e.g., refrigerator, television, air conditioner, electricity meter, etc.), smart robot, robotic arm, workshop equipment, wireless terminal in self-driving, wireless terminal in remote medical surgery, wireless terminal in smart grid, wireless terminal in transportation safety, wireless terminal in smart city, wireless terminal in smart home, flying equipment (e.g., smart robot, hot air balloon, drone, airplane), etc. Terminals can also be vehicle devices, such as vehicle units, vehicle modules, vehicle chips, on-board units (OBUs), or telematics boxes (T-BOXs).A terminal can also be other devices with terminal functions. For example, a terminal can also be a device that plays a terminal function in device-to-device (D2D) communication.

[0087] Terminals can be widely used in a variety of scenarios. For example, device-to-device communication, vehicle-to-machine communication, Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, smart cities, etc.

[0088] In some implementations, the terminal can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; it can also be deployed on water (such as on ships); and it can also be deployed in the air (such as on airplanes, balloons, and satellites). In the embodiments of this application, the device for implementing the terminal's functions can be the terminal itself; or it can be a device capable of supporting the terminal in implementing those functions, such as a chip system, which can be installed in the terminal. In the embodiments of this application, the chip system can be composed of chips, or it can include chips and other discrete devices.

[0089] In some implementations, the terminal can act as a base station. Optionally, the terminal can act as a scheduling entity, providing sidelink signals between terminals in vehicle-to-everything (V2X) or device-to-device (D2D) communication. For example, cellular phones and cars can communicate using sidelink signals, or cellular phones and smart home devices can communicate using sidelink signals without relaying communication signals through a base station. In the technical solutions provided in the embodiments of this application, the device for implementing the functions of the terminal is the terminal, and the terminal is a UE, as an example to describe the technical solutions provided in the embodiments of this application.

[0090] In this application, the access network device can refer to a radio access network (RAN) node (or device) that connects a terminal to a wireless network, and can also be called a base station (BS), RAN entity, or access node. A BS can be a device deployed in a radio access network capable of wireless communication with a terminal. For example, the access network device can be a NodeB, an evolved NodeB (eNB), a next-generation NodeB (gNB) in a 5G mobile communication system, a transmission reception point (TRP), an access point (AP), an access network device in a non-terrestrial network (NTN) system (such as a satellite), a base station in a future mobile communication system, an access point (AP) in a WiFi system, a radio controller, relay station, access point, vehicle-mounted equipment, wearable device, or access network device in other future evolved communication systems, etc.

[0091] In this embodiment, the terminal or access network device may include a hardware layer, an operating system layer running on top of the hardware layer, and an application layer running on top of the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and memory (also called main memory). The operating system can be any one or more computer operating systems that implement business processing through processes. The application layer includes applications such as browsers, address books, word processing software, and instant messaging software. Furthermore, this embodiment does not specifically limit the specific structure of the execution entity of the method provided in this embodiment, as long as it can communicate according to the method provided in this embodiment by running a program that records the code of the method provided in this embodiment.

[0092] Communication between access network devices and terminals follows a specific protocol layer structure. This protocol layer may include a control plane protocol layer and a user plane protocol layer. The control plane protocol layer may include at least one of the following: radio resource control (RRC) layer, packet data convergence protocol (PDCP) layer, radio link control (RLC) layer, media access control (MAC) layer, or physical (PHY) layer, etc. The user plane protocol layer may include at least one of the following: service data adaptation protocol (SDAP) layer, PDCP layer, RLC layer, MAC layer, or physical layer, etc.

[0093] In some implementations, multiple radio access network (RAN) nodes can collaborate to assist a terminal in achieving wireless access, with different RAN nodes each implementing some of the base station's functions. For example, a RAN node (i.e., the network device in this application) can be a central unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU), etc. The CU and DU can be configured separately or included in the same network element, such as in a baseband unit (BBU). The RU can be included in radio frequency equipment or radio frequency units, such as in a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

[0094] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. For example, in an open radio access network (ORAN) system, CU can also be called an open CU (open CU, O-CU), DU can also be called an open DU (open DU, O-DU), CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software modules and hardware modules. It should be understood that this application does not limit the specific technology or specific device form used in the network equipment.

[0095] O-RAN aims to achieve an intelligent and open access network. A key feature of the O-RAN architecture is the separation of hardware and software, enabling the virtualization of network functions and the standardization of hardware. Furthermore, O-RAN incorporates artificial intelligence (AI).

[0096] Core network equipment refers to the equipment within the Network Center (CN) that provides service support to terminals. Core network equipment can correspond to different devices in different systems. For example, in 3G, it may correspond to the Serving GPRS Support Node (SGSN) and / or the Gateway GPRS Support Node (GGSN). Core network equipment can be one or more of the following: access and mobility management function (AMF) and network data analytics function (NWDAF). In 4G, it may correspond to the Mobility Management Entity (MME) and / or the Serving Gateway (S-GW). In 5G, it may correspond to the Access and Mobility Management Function (AMF) entity, the Session Management Function (SMF) entity, or the User Plane Function (UPF) entity.

[0097] Clause 23.501 of the 3GPP technical specifications (TS) defines the service-based architecture (SBA) of 5G systems. The 5G system architecture consists of two parts: the access network and the core network. The following section will combine... Figure 2 The diagram shown illustrates the 5G network architecture and explains some core network equipment.

[0098] The main functions of the Access and Mobility Management (AMF) entity include managing user registration, reachability detection, selecting SMF nodes, and managing mobility state transitions. In future communication systems, the Access and Mobility Management entity may still be an AMF entity, or it may have other names; this application does not limit this.

[0099] The main functions of SMF are to control the establishment, modification, and deletion of sessions, and the selection of user plane nodes. In future communication systems, the session management function entity can still be an SMF entity, or it can have other names; this application does not limit this.

[0100] The main function of the policy control function (PCF) entity is the policy decision point, providing rules based on business data flow and application detection, gating, quality of service (QoS), and flow-based billing control.

[0101] The primary function of the authentication server function (AUSF) entity is to provide authentication services.

[0102] The function of the Network Exposure Function (NEF) entity is to securely expose services and capabilities provided by 3GPP network functions, such as third-party, edge computing, and application functions.

[0103] The Network Data Analytics Function (NWDAF) entity provides network data collection and analysis capabilities based on technologies such as big data and artificial intelligence.

[0104] A service communication proxy (SCP) can be used for indirect communication between network functions (NFs). Service requests from NFs can be proxied by the SCP.

[0105] Data management (DM) entity: Used to handle user equipment identification, access authentication, registration, and mobility management. In 5G communication systems, data management can be a unified data management (UDM) entity, whose main function is to store user subscription data.

[0106] The primary function of an access network (AN) node is to provide wireless connectivity, and it is located between the UE and the core network node.

[0107] The main function of an application function (AF) entity is to interact with the 3GPP core network to provide services, influencing service flow routing, access network capability opening, policy control, etc.

[0108] The primary function of the User Plane Function (UPF) is to act as an interconnection point between mobile infrastructure (e.g., RAN) and data network (DN), performing functions such as uplink (UP) GTPU protocol encapsulation and decapsulation, packet routing and forwarding, packet inspection, and accounting. It enables packet routing and forwarding, mobility anchoring, and uplink classifiers to support routing traffic to the data network, and branch points to support multi-homed protocol data unit (PDU) sessions. In future communication systems, the User Plane Function entity can still be a UPF entity, or it can have other names; this application does not limit this. Here, GTPU is an abbreviation for General Packet Radio Service (GPRS) Tunneling Protocol User Plane (GTPU).

[0109] Data network (DN): A network used to provide data transmission, such as carrier services, internet access, or third-party services.

[0110] It should be noted that the entities in the embodiments of this application can also be referred to as network elements or functional entities. For example, an AMF entity can also be referred to as an AMF network element or an AMF functional entity, and an SMF entity can also be referred to as an SMF network element or an SMF functional entity, etc.

[0111] Figure 2N1, N2, N3, N4, N6, N9, Nnwdaf, Nnef, Nnrf, Npcf, Nudm, Naf, Nausf, Namf, and Nsmf are interface sequence numbers. The meanings of these interface sequence numbers can be found in the definition of 3GPP TS 23.501.

[0112] In a 5G system, functional units can communicate with each other through next-generation (NG) interfaces. For example, a UE can transmit control plane messages with an AMF network element through NG interface 1 (N1), a RAN can establish a user plane communication connection with a UPF network element through NG interface 3 (N3), an AN / RAN device can establish a control plane signaling connection with an AMF network element through NG interface 2 (N2), a UPF network element can exchange information with an SMF network element through NG interface 4 (N4), and a UPF network element can exchange user plane data with a DN network element through NG interface 6 (N6).

[0113] It should be understood that the network architecture described above for the embodiments of this application is merely illustrative, and the network architecture applicable to the embodiments of this application is not limited thereto. Any network architecture capable of implementing the functions of the above-described network elements is applicable to the embodiments of this application. It should be noted that... Figure 2 The AMF, SMF, UPF, NEF, PCF, UDM, NWDAF, NRF, AUSF, SCP, etc. shown can be understood as network elements in the core network used to implement different functions, such as network slices that can be combined as needed. These core network elements can be independent devices or integrated into the same device to implement different functions. This application does not limit the specific form of the above network elements.

[0114] It should be noted that the aforementioned "network element" can also be referred to as an entity, device, apparatus, or module, etc., and this application does not specifically limit it. In this application, for ease of understanding and explanation, the description of "network element" is omitted in some descriptions. For example, the AMF network element is abbreviated as AMF. In this case, "AMF" should be understood as an AMF network element or an AMF entity. The following omits descriptions of the same or similar cases. The aforementioned network element can be a network component in a hardware device, a software function running on dedicated hardware, or a virtualized function instantiated on a platform (e.g., a cloud platform).

[0115] It should also be understood that the above naming is defined solely for the purpose of distinguishing different functions and should not constitute any limitation on this application. This application does not preclude the possibility of using other naming conventions in 5G networks and other future networks. For example, in 6G networks, some or all of the aforementioned network terminology may be retained from 5G, or other names may be used. Figure 2The interface names between the various network elements are merely examples; in actual implementations, the interface names may differ, and this application does not impose any specific limitations on them. Furthermore, the names of the messages (or signaling) transmitted between the aforementioned network elements are also merely examples and do not constitute any limitation on the function of the messages themselves.

[0116] Figure 2 The network elements in the communication system shown can be shared with or have interactive interfaces opened with network elements in other communication systems to achieve interaction between networks of different standards. Figure 3 This is a schematic diagram of the network architecture for the interaction between 5G and 4G networks applicable to embodiments of this application. The following is in conjunction with… Figure 3 The diagram shown illustrates the network interaction architecture and explains some core network devices of the 4G network.

[0117] The MME is a core network element in the 4G network responsible for UE authentication, authorization, mobility management, and session management. The Evolved Packet System (EPS) bearer identifier (EBI) for the UE's packet data network (PDN) connection in the 4G network can be assigned by this network element.

[0118] Serving Gateway (SGW): The gateway that terminates the RAN user plane interface, performing functions such as lawful monitoring and packet data routing. The interface between the SGW and the MME is the S11 interface, which is responsible for the exchange of session control information between terminals.

[0119] A Packet Data Network Gateway (PGW) is a gateway terminating at the SGi interface of the packet data network. It provides functions such as bearer control, data forwarding, IP address allocation, and access for non-3GPP users. It serves as the anchor point for both 3GPP and non-3GPP access public data networks. The PGW has packet routing and forwarding capabilities and is responsible for policy-based charging enhancements and user-based packet filtering. The PGW connects to the SGW via the S5 interface, transmitting control information such as information establishment, modification, and deletion, as well as packet data routing. The interface between the PGW-U and the data network can be called the SGi interface.

[0120] The 3GPP protocol describes the control and user plane separation (CUPS) configuration in an EPC network architecture. The Service Gateway (SGW) can be split into a Serving Gateway for the User Plane (SGW). U) and the serving gateway for controlplane (SGW) C). PGW can be split into a packet data network gateway for user plane (PGW). U) and the control plane PDN gateway (packet data network gateway for controlplane, PGW) C). Among them, PGW The C-type network element is responsible for terminal session management and bearer control, as well as Internet Protocol (IP) address allocation and billing support. The interface between PGW-C and PGW-U can be called the Sxb interface.

[0121] The home subscriber server (HSS) is a server in the 4G network used to store user subscription information.

[0122] Authentication, authorization, and accounting (AAA) is used to achieve centralized control over user authentication, access permission allocation, and resource usage billing.

[0123] Optionally, 5G networks can share network elements with 4G networks (such as SMF and PGW). C-unit, UPF and PGW U-type co-location, UDM and HSS co-location, etc., and / or opening interactive interfaces (such as opening an N26 interface between AMF and MME) to realize interaction between the two networks.

[0124] The deployment and application of 5G local area networks (LANs) in 5G mobile communication networks are accelerating. A 5G LAN utilizes 5G technology to group terminal users into a single LAN network. While traditional PDU connections solve the data exchange problem between terminals and data networks (DNs), 5G LANs add the concept of groups. Terminals belonging to the same 5G LAN group can exchange data with the data network corresponding to that group, and can also directly exchange data with other terminals within the group through UPF network elements, with terminals in different groups being isolated from each other. Virtual private network (VPN) communication can be achieved through 5G LANs. 5G LANs offer flexible deployment and direct interoperability, demonstrating excellent performance in network deployment, network determinism, and ultra-reliable low-latency communication (URLLC). They promote the deep integration of information technology (IT) and operational technology (OT) in the industrial internet and play a crucial role in supporting the construction of fully connected factories.

[0125] In the Open Systems Interconnection (OSI) seven-layer network model, the data link layer is abbreviated as layer 2 (L2) and uses the Ethernet protocol. The network layer in the OSI seven-layer network model is abbreviated as layer 3 (L3) and uses the Internet Protocol (IP).

[0126] The 3GPP standard defines 5G LANs as supporting both L2 and L3 communication modes. L2 mode refers to the transmission of Ethernet packets to terminals in the 5G network, requiring no IP address allocation for the terminals. L3 mode refers to the transmission of IP packets in the 5G network, requiring IP address allocation for the terminals. In practical applications, L2 mode is primarily used for interoperability within 5G LANs, as it requires minimal modification to existing enterprise networks. While 4G network PDN sessions use an IP version, 5G network PDU sessions include both IP and Ethernet versions.

[0127] When a terminal establishes a PDU session, if the PDU session type is the Ethernet version, the AMF network element selects an SMF network element for the user based on the data network name (DNN) and the slice. The SMF network element obtains the user's subscription information from the UDM network element, including information about the 5G virtual network (VN) group the user has subscribed to. The SMF network element identifies the terminal as a 5G LAN user based on the subscribed 5G VN group. A 5G LAN group session is created based on the VN group, with one group session corresponding to each VN group. Then, a user session is created and associated with the group session of that VN group. The forwarding logic within the 5G VN group may include: broadcast messages within the VN group are copied and distributed to all users within the group; terminals within the group can communicate with each other, but communication between different groups is not allowed.

[0128] 3GPP defines 5G LAN as supporting only 5G network standards and not 2G / 3G / 4G networks. This means that current 5G LAN can only be used in 5G network environments; there are no 5G LAN standards for 4G network scenarios. Users want to use the L2 forwarding mode of 5G LAN, but 5G base station coverage is incomplete, and L2 forwarding cannot be implemented under 4G base stations. This requires increased investment from customers and operators, hindering the expansion of 5G LAN services and making it difficult for terminals to maintain uninterrupted service during 4G / 5G network handover scenarios.

[0129] To address one or more of the aforementioned technical problems, this application proposes a communication method that facilitates the transmission of Ethernet packets when a terminal accesses a VN group under an IP-type session. Figure 4 This is a flowchart illustrating a communication method provided in an embodiment of this application. Figure 4 The communication method S400 shown can be applied to a communication device. This communication device can be a control plane network element in the core network. Alternatively, the communication device can be a component or device (e.g., a processor, chip, or chip system) of a control plane network element. Or, the communication device can be a logic module or software capable of implementing all or part of the functions of the control plane network element. The control plane network element can be a PGW-C network element or an SMF network element in the core network. The PGW-C and SMF network elements can be independent network elements, or they can be shared network elements. This communication method S400 can also be applied to user plane network elements, which can be PGW-U network elements or UPF network elements. The PGW-U and UPF network elements can be independent network elements, or they can be shared network elements. Figure 4 The communication method S400 shown can also be applied to RAN (eNB), UDM network elements, AAA network elements, terminals, etc. The terminal can be any of the terminals mentioned above.

[0130] The following is combined with Figure 3 , Figure 4 The communication method S400 in the embodiments of this application will be described in detail. For example, a 4G network will be used as an example. In the core network of a 4G network, the control plane network element can be a PGW-C network element, and the user plane network element can be a PGW-U network element. Figure 4 The communication method S400 shown can mainly include steps S430 to S480, which are described in detail below.

[0131] It should be noted that the sequence number of each step in the embodiments of this application does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0132] In step S430, the PGW-C network element receives a session establishment request message initiated by the terminal, which is an IP type session.

[0133] The session establishment request message includes the PDN session type information and the terminal's characteristic identifier. The PGW-C network element can determine that the PDN session type is IP. The session establishment request message is also called a session establishment request or a session generation request, and this application does not limit it to these terms.

[0134] In some implementations, the terminal's identifier may include at least one of the following: DNN, generic public subscription identifier (GPSI), or subscription concealed identifier (SUPI). Specifically, the DNN identifies the external data network the user intends to access, the GPSI is used to mark the terminal outside the 3GPP system, and the SUPI is used to mark the terminal within the 3GPP system.

[0135] Specifically, step S430 may include multiple sub-steps, such as steps S431 to S434.

[0136] In step S431, the terminal sends a PDN connection request to the MME network element. Correspondingly, the MME network element receives the PDN connection request.

[0137] In step S432, the MME network element sends a Create Session Request to the SGW-C network element. Correspondingly, the SGW-C network element receives the Create Session Request.

[0138] In step S433, the SGW-C network element sends a corresponding session creation request (Create SessionReq) to the SGW-U network element, and the SGW-U network element sends a corresponding session creation response (Create Session Rsp) to the SGW-C network element.

[0139] In step S434, the SGW-C network element sends a Create Session Request to the PGW-C network element. This request includes the terminal's identifier. Correspondingly, the PGW-C network element receives the Create Session Request.

[0140] In step S450, the PGW-C network element obtains the subscription information of the VN group corresponding to the terminal. The subscription information of the VN group includes the VN group identifier (VN Group ID).

[0141] The subscription information for a Virtual Network Group (VN) can be the subscription information for a 5G VN group. The 5G VN group subscription information is fundamental to 5G LAN services, defining the membership rules for the entire virtual network. The 5G VN group subscription information typically includes: VN group identification information, VN group membership information, VN group communication policies, and VN group data network characteristics. Among these, the VN group identification information can include: the VN Group ID, which is a unique identifier for the virtual network group. The VN Group ID can be considered an external identifier for the VN group, associating it with the network resources, policies, and configurations defined for that VN group. In a 5G network, there are usually multiple VN groups, each corresponding to a different VN Group ID.

[0142] VN group member information may include: a member list, i.e., a list of terminals authorized to access the VN group. The VN group's communication policy defines the communication rules within and outside the group. VN group data network characteristics may include: PDU session type, L2 / L3 forwarding configuration, IP address management, etc. The VN group supports PDU session types of Ethernet or IP. L2 / L3 forwarding configuration: For Ethernet VN groups, MAC address management policies can be configured to define the handling methods for broadcast / multicast / unknown unicast.

[0143] The PGW-C network element obtains the subscription information of the VN group corresponding to the terminal in order to obtain information such as the VN group identifier and the VN group communication policy.

[0144] VN group subscription information is typically stored in UDM or AAA network elements. When a terminal establishes a PDN session, it needs to query this information to verify whether the terminal can join a certain VN group and to determine the attributes and policies of that VN group.

[0145] In step S460, the PGW-C network element creates a group session corresponding to the VN group based on the VN group's subscription information. This group session corresponds to the VN group to which the terminal belongs, and one VN group corresponds to one 5G LAN.

[0146] A terminal can correspond to multiple VN groups, and a VN group includes multiple terminals. Each VN group has a unique VNGroup ID. There is a correspondence between the group session and the VN Group ID; different group sessions can be distinguished by the VN Group ID. Before a terminal joins a VN group for intra-group communication, it needs to create a group session corresponding to the VN group.

[0147] In some implementations, creating the group session corresponding to the VN group in step S460 may specifically include steps S463 to S464.

[0148] In step S463, the PGW-C network element initiates a Packet Forwarding Control Protocol (PFCP) group session establishment request (Session Establishment request) to the PGW-U network element. The group session establishment request includes some or all of the subscription information from the VN group. For example, the group session establishment request includes the VN group identifier, which corresponds to the group session. Correspondingly, the PGW-U network element receives the group session establishment request sent by the PGW-C network element. The interface between the PGW-C network element and the PGW-U is an Sxb interface, which uses the PFCP protocol.

[0149] In step S464, the PGW-U network element sends a PFCP group session establishment response message (SessionEstablishment rsp) to the PGW-C network element.

[0150] The PFCP group session response message may include: the IP information of the Virtual Extended LAN (VXLAN) tunnel endpoint (VTEP) of the PGW-U network element, and the VXLAN network identifier (VNI) corresponding to the terminal. The IP address of the VTEP of the PGW-U network element is used to locate the PGW-U network element and serves as the endpoint for establishing the data tunnel. The VNI is used to identify the virtual extended LAN network corresponding to the terminal, enabling service or slice isolation within the virtual network and identifying the attribution of data frames. The IP information of the VTEP and the VNI of the PGW-U network element are used to configure the tunnel of the VN group, which is used for the transmission of Ethernet packets between the PGW-U network element and the terminal.

[0151] The creation of a group session corresponding to a VN group clarifies the specific interaction steps between control plane network elements and user plane network elements. The group session establishment response includes the IP information of the user plane network element's VTEP and the VNI corresponding to the terminal, used to configure the VN group's tunnel for subsequent user plane data transmission based on this tunnel.

[0152] In step S470, the PGW-C network element sends a Layer 2 forwarding identifier and a VN group identifier to the PGW-U network element. The Layer 2 forwarding identifier is used to trigger the user plane network element (such as the PGW-U network element) to perform Layer 2 forwarding of Ethernet packets received under IP type sessions. Alternatively, the Layer 2 forwarding identifier is used to trigger the user plane network element to receive and forward Ethernet packets under IP type sessions. The VN group identifier is also used to associate with group sessions of the VN group.

[0153] Accordingly, the PGW-U network element receives the Layer 2 forwarding identifier and the VN group identifier. The PGW-U network element can perform Layer 2 forwarding of Ethernet packets received through IP type sessions based on the Layer 2 forwarding identifier.

[0154] After creating the PFCP group session corresponding to the VN group, the PGW-C network element sends the Layer 2 forwarding identifier and the VN group identifier to the PGW-U network element so that the PGW-U network element can perform Layer 2 forwarding within the VN group for Ethernet packets received under the IP type session.

[0155] It should be noted that user plane network elements can, based on the identifier of a VN group, allow data transmission between a terminal and other terminals in that VN group, but disallow intra-group data transmission between a terminal and terminals in other VN groups.

[0156] For example, if the Ethernet packet sent by the terminal contains the VXLAN network identifier (i.e., VNI), the PGW-U network element can map the VNI to different VN groups to identify the VN group to which the Ethernet packet belongs. There is a mapping relationship between the VNI and the VN group identifier.

[0157] For example, there is a mapping table between MAC addresses and VN groups, and VN groups are marked based on their identifiers. UPF network elements can identify different VN groups based on MAC addresses, and the VN group to which a terminal belongs can be identified through its source MAC address.

[0158] In some implementations, sending the Layer 2 forwarding identifier and the VN group identifier to the user plane network element in step S470 may specifically include steps S471 to S472.

[0159] In step S471, the PGW-C network element sends a PFCP user session establishment request (SessionEstablishment req) to the PGW-U network element. The PFCP user session establishment request includes a Layer 2 forwarding identifier and a VN group identifier; the PFCP user session is associated with the group session to which the terminal belongs. Accordingly, the PGW-U network element receives the PFCP user session establishment request.

[0160] Alternatively, the PGW-C network element notifies the PGW-U network element that it is required to enable the relevant configuration for Layer 2 forwarding of IP type sessions, so that the PGW-U network element and the terminal can transmit Ethernet packets based on Layer 2 forwarding.

[0161] PFCP user sessions can be associated with the group session to which the terminal belongs based on the VN group identifier. Optionally, the PFCP user session establishment request may also include: the user's requesting IP address. The IP address is the logical identifier of the terminal in the data network. The user's requesting IP address is associated with the forwarding policy of the VN group.

[0162] In step S472, the PGW-U network element sends a PFCP user session establishment response (Session Establishmentreq), and correspondingly, the PGW-C network element receives the PFCP user session establishment response.

[0163] The PGW-U network element configures the forwarding of IP type session lower layer 2 packets according to the layer 2 forwarding identifier and the VN group identifier, and sends a PFCP user session establishment response message to the PGW-C network element to indicate the result of the user session establishment.

[0164] In step S480, the PGW-C network element sends a session establishment response message to the terminal. This message includes a Layer 2 forwarding identifier, which also triggers the terminal to process packets received through the IP type session as Ethernet packets, or to encapsulate data to be sent through the IP type session into Ethernet packets before sending. In other words, it triggers the terminal to receive or send Ethernet packets under the IP type session.

[0165] The aforementioned terminal processes the packets received through the IP type session as Ethernet packets, which may include: if the terminal is a communication endpoint, the terminal decapsulates the packets received through the IP type session as Ethernet packets; if the terminal is a bridging node (such as CPE) or gateway, based on the MAC address table, the terminal can directly forward the Ethernet packets received through the IP type session.

[0166] The session establishment response information can carry protocol configuration options (PCOs). For example, the PCO can be extended to carry a Layer 2 forwarding identifier. The PCO is used to transmit dynamic configuration parameters when establishing a PDN / PDU connection in an LTE / 5G network, and can provide the terminal with additional network-related information.

[0167] In some implementations, the session establishment response information (or in the PCO) can be extended to include: a Layer 2 forwarding identifier, the IP information of the VTEP of the PGW-U network element, and the VNI corresponding to the terminal. The IP information of the VTEP of the PGW-U network element is used to configure the tunnel of the VN group, which is used for the transmission of Ethernet packets between the PGW-U network element and the terminal. The VNI is used to identify the VXLAN network corresponding to the terminal. In VXLAN encapsulation, the VXLAN header of the packet contains the VNI characters to distinguish different virtual network groups.

[0168] The session establishment response message sent to the terminal includes the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal. It is used to configure the tunnel of the VN group on the terminal side so that Ethernet packets can be transmitted based on the tunnel in the future.

[0169] Specifically, the process of sending the response information for establishing the PDN session in step S480 may include steps S481 to S482.

[0170] In step S481, the PGW-C network element sends a PDN session establishment response message to the SGW-C network element. This response message may carry a PCO, which may carry a Layer 2 forwarding identifier. Correspondingly, the SGW-C network element receives the PDN session establishment response message.

[0171] In step S482, the SGW-C network element sends a PDN session establishment response message to the MME network element. This response message may carry a PCO, which may carry a Layer 2 forwarding identifier. Correspondingly, the MME network element receives the PDN session establishment response message.

[0172] In step S483, the MME network element sends a PDN session connection accept (PDN Connectivity Accept) to the terminal, which is equivalent to sending an Activity Default EPS Bearer CONTEXT REQUEST. This session connection accept can carry a PCO, which can carry a Layer 2 forwarding identifier. Correspondingly, the terminal receives the PDN session connection accept.

[0173] Optionally, the PCO may include: a Layer 2 forwarding identifier, the IP information of the VTEP of the PGW-U network element, and the VNI corresponding to the terminal.

[0174] The terminal has the capability to forward Layer 2 packets under IP session type. Upon receiving the Layer 2 forwarding identifier, it initiates the Layer 2 packet forwarding function under IP session type. This facilitates the timely activation of the Layer 2 packet forwarding function under IP session type according to application requirements.

[0175] In some implementations, the session establishment response information may not include the Layer 2 forwarding identifier. The terminal side can pre-configure the Layer 2 forwarding identifier, that is, pre-enable the function of encapsulating data to be sent into Ethernet packets before sending under IP-type sessions, or the function of processing packets received through IP-type sessions as Ethernet packets. In other words, the function of forwarding Layer 2 packets under IP-type sessions is always enabled. Based on the pre-configured Layer 2 forwarding identifier, it helps to reduce the configuration of the Layer 2 forwarding identifier in the session establishment response information sent by PGW-C network elements, thus reducing the amount of information in the session establishment response information.

[0176] Optionally, the terminal side can also pre-configure the Layer 2 forwarding identifier, the IP information of the VTEP of the PGW-U network element, and the VNI corresponding to the terminal, and configure the tunnel of the VN group so that Ethernet packets can be transmitted based on the tunnel in the future.

[0177] Through steps S470 and S480, the PGW-U network element starts the function of forwarding Ethernet packets received under IP type sessions at Layer 2, and the terminal starts receiving or sending Ethernet packets under IP type sessions.

[0178] In this embodiment, the PGW-C network element obtains the subscription information of the VN group corresponding to the terminal, and creates a group session corresponding to the VN group based on the subscription information. It sends a Layer 2 forwarding identifier and the VN group identifier to the user plane network element to trigger the PGW-U network element to perform Layer 2 forwarding of Ethernet packets received under the IP type session. It also sends a session establishment response message including the Layer 2 forwarding identifier to the terminal to trigger the terminal to process packets received through the session as Ethernet packets, or to encapsulate data to be sent through the session into Ethernet packets before sending. This embodiment facilitates the terminal's access to the 4G network via an IP type session, enabling Layer 2 packet transmission with other terminals within the 5G VN group, and access to N6-side services in a Layer 2 manner. N6-side services refer to all data traffic and applications generated by terminals (mobile phones, CPEs, IoT devices, etc.) accessing external data networks through the UPF network element of the 5G core network.

[0179] In some implementations, before step S430, the method S400 of this application embodiment may further include steps S410 to S420.

[0180] In step S410, the PGW-C network element is pre-configured with a preset identifier set. The preset identifier set may include multiple feature identifiers, and the terminal corresponding to any of the multiple feature identifiers supports the transmission of Ethernet packets under IP type sessions.

[0181] The preset identifier set can be a collection of feature identifiers corresponding to multiple terminals in a VN group. Alternatively, the preset identifier set can be a collection of feature identifiers corresponding to multiple terminals in multiple VN groups. The PGW-C network element is pre-configured with the preset identifier set so that in subsequent processes, it can identify whether a terminal is transmitting Ethernet packets under an IP type session based on the terminal's feature identifiers.

[0182] In step S411, the UDM network element pre-configures the user's subscription information.

[0183] A user's subscription information is a complete user service configuration profile stored in the operator's network database (such as UDM). UDM network elements can identify the user's identity through the International Mobile Subscriber Identity (IMSI), authorize the user to access the network, and provide corresponding services based on the subscription information bound to the IMSI. The IMSI is a permanent and unique identifier for a mobile user. In 5G networks, the identifier corresponding to the IMSI is SUPI.

[0184] For example, for a 4G network, a user's subscription information may include: IMSI1, Access Point Name (APN) / DNN is APN1, and PDN session type is IP. For a 5G network, a user's subscription information may include: SUPI1, APN / DNN is APN1, PDU session type is IP or Ethernet, and VN group is **cde. It should be noted that a terminal can join multiple VN groups.

[0185] In step S420, the terminal completes the user registration process.

[0186] The general registration and network access process for terminals can be simply described as follows: The terminal sends a registration request to the MME network element through the access network device. The MME network element obtains the subscription data from the specific HSS network element based on the terminal's user identifier. After a series of authentication and authorization operations, the network side finally confirms that the terminal is allowed to access the network. At this time, the MME network element responds to the terminal's registration request and sends relevant policy information to the terminal, and the terminal completes network registration and residency. The MME network element maintains the terminal's registration and network access information and performs mobility management for the terminal.

[0187] In some implementations, obtaining the subscription information of the VN group corresponding to the terminal in step S450 above may include: the PGW-C network element obtaining the identifier of the shared VN group data corresponding to the terminal; and obtaining the subscription information of the VN group corresponding to the terminal based on the identifier of the shared VN group data. Alternatively, before obtaining the subscription information of the VN group corresponding to the terminal in step S450, the method of this application embodiment may further include step S440.

[0188] In step S440, the PGW-C network element obtains the identifier (shareVnGroupDataIds) of the shared VN group data corresponding to the terminal.

[0189] Under a 4G network, a terminal can simulate 5G access to obtain the user's 5G subscription information from the UDM network element. The user's 5G subscription information may include information such as `shareVnGroupDataIds`. `shareVnGroupDataIds` is a mapping (a list of key-value pairs, where the Group ID is the key) of 5G shared VN group data identifiers. `shareVnGroupDataIds` is the VN group identifier within the UDM, indicating the VN group to which the terminal belongs, and typically does not contain network policies or resource configurations. There is a mapping relationship between the VN Group ID and `shareVnGroupDataIds`.

[0190] When a terminal establishes a PDN session, it needs to query this information to verify whether the terminal can join a certain VN group.

[0191] Optionally, obtaining the identifier of the shared VN group data corresponding to the user in step S440 may include: obtaining the user's 5G subscription information, whereby the user's 5G subscription information includes the identifier of the shared VN group data corresponding to the user. Specifically, the process of obtaining the user's 5G subscription information (or step S440) may include steps S441 to S442.

[0192] In step S443, the PGW-C network element sends a request message (Nudm_SDM_GetUESession managementSubscriptionData_Request) to the UDM network element to obtain the user's 5G subscription information (or subscription data).

[0193] In step S443, the UDM network element sends a response message (Nudm_SDM_GetUESession managementSubscriptionData_Response) to the PGW-C network element to obtain the terminal subscription information, i.e., returns the user's 5G subscription information. The user's 5G subscription information may include: the subscribed PDU type and the identifier of the 5G shared VN group data. The PDU type can be Ethernet or IP. The identifier of the shared VN group data is used to obtain the subscription information of the VN group corresponding to the terminal. If the user has not subscribed to the services related to that VN group, the returned 5G subscription information will not include the identifier of the 5G shared VN group data.

[0194] In 4G networks, during the establishment of a PDN session, the MME network element typically obtains the user's subscription information from the HSS network element. Unlike the process in 4G networks, in this embodiment, the PGW-C network element obtains the user's 5G subscription information from the UDM network element.

[0195] The session establishment request message received by the PGW-C network element includes the terminal's identifier. Based on this identifier, the PGW-C network element can determine whether the terminal supports Ethernet packet forwarding under IP type sessions.

[0196] In some implementations, obtaining the identifier of the shared VN group data corresponding to the terminal in step S440 may include: obtaining the identifier of the shared VN group data corresponding to the terminal when it is determined that the feature identifier of the terminal matches the feature identifier in a preset identifier set. Wherein, the terminal corresponding to any feature identifier in the preset identifier set supports the transmission of Ethernet packets under IP type sessions.

[0197] Only when the terminal has the ability to transmit Ethernet packets under IP type sessions can the function of transmitting Ethernet packets be enabled under IP type sessions, which can simulate 5G network access to obtain the user's 5G VN group subscription information.

[0198] After identifying that the terminal supports the transmission of Ethernet packets under IP type sessions, the identifier of the shared VN group data corresponding to the terminal is obtained. For terminals that do not support Layer 2 forwarding, this helps to avoid PGW-C network elements sending invalid request signaling to UDM network elements, reducing the amount of data exchanged in signaling.

[0199] Optionally, before the PGW-C network element receives the identifier of the shared VN group data corresponding to the terminal in step S440, or before the PGW-C network element sends a request message to the UDM network element to obtain the terminal subscription information in step S443, the method S400 of this application embodiment may further include step S441.

[0200] In step S441, it is determined that the feature identifier of the terminal matches a feature identifier in a preset identifier set.

[0201] By comparing the terminal's characteristic identifier with a preset identifier set, it quickly identifies whether the terminal supports the transmission of Ethernet packets under IP type sessions. For terminals that do not support the transmission of Ethernet packets under IP type sessions, it avoids the PGW-C network element sending invalid request signaling to the UDM network element, reducing the amount of data exchanged in signaling.

[0202] In some implementations, obtaining the subscription information of the VN group corresponding to the terminal in step S450 may include: the PGW-C network element receiving the subscription information of the VN group from the UDM network element; or, receiving the subscription information of the VN group from the AAA network element.

[0203] The subscription information for 5G VN groups is stored in the UDM network element and can be obtained from the UDM network element; the subscription information for 5G VN groups is stored in the AAA network element and can be obtained from the AAA network element.

[0204] Optionally, the PGW-C network element receives VN group subscription information from the UDM network element. Specifically, this may include: the PGW-C network element sending a VN group subscription information request message to the UDM network element, the VN group subscription information request message including an identifier for shared VN group data. After receiving the VN group subscription information request message, the UDM network element finds the VN group subscription information corresponding to the identifier of the shared VN group data, and sends the terminal's corresponding VN group subscription information to the PGW-C network element. Correspondingly, the PGW-C network element receives the terminal's corresponding VN group subscription information.

[0205] The specific interaction steps for the PGW-C network element to obtain the 5G VN group subscription information from the UDM network element based on the identifier of the 5G shared VN group data are clarified.

[0206] Optionally, the PGW-C network element receives the VN group subscription information sent by the AAA network element. Specifically, this may include: the PGW-C network element sending a request message for VN group subscription information to the AAA network element, which includes SUPI and APN. After receiving the VN group subscription information request message, the AAA network element sends the user's subscription information corresponding to the terminal to the PGW-C network element according to the SUPI and APN in the request message. The user's subscription information includes the VN group subscription information. Correspondingly, the PGW-C network element receives the VN group subscription information corresponding to the terminal. For example, during session establishment, the PGW-C network element sends an authentication request (Access Request) message (i.e., a VN group subscription information request message) to the AAA network element. After successful user authentication, the AAA network element returns the user's subscription information in its response message, which includes the 5G VN group subscription information.

[0207] The specific interaction steps for control plane network elements to obtain VN group subscription information from AAA network elements based on SUPI and APN are clarified.

[0208] In some implementations, step S460, which involves creating a group session corresponding to a VN group based on the VN group's subscription information, may include: if it is determined that the terminal's feature identifier matches a feature identifier in a preset identifier set, then creating a group session corresponding to the VN group based on the VN group's subscription information. Wherein, any terminal corresponding to any feature identifier in the preset identifier set supports transmitting Ethernet packets under IP type sessions.

[0209] After identifying that the terminal supports the transmission of Ethernet packets under IP type sessions, the group session corresponding to the VN group is created. For terminals that do not support Layer 2 forwarding, the PGW-C network element is prevented from sending invalid group session creation request signaling to the PGW-U network element, thereby reducing the amount of data exchanged in the signaling.

[0210] Optionally, before creating the group session corresponding to the VN group in step S460, or before the PGW-C network element initiates a request to the PGW-U network element to establish a PFCP group session in step S463, the method S400 of this application embodiment may further include step S461.

[0211] In step S461, it is determined that the feature identifier of the terminal matches a feature identifier in a preset identifier set.

[0212] The system compares the terminal's characteristic identifier with a preset identifier set to determine whether the terminal supports transmitting Ethernet packets under IP type sessions. For terminals that do not support Layer 2 forwarding, it prevents PGW-C network elements from sending invalid group session creation request signaling to PGW-U network elements.

[0213] Through steps S410 to S480, the PGW-C network element completes session negotiation with the PGW-U network element and the terminal, respectively. Specifically, the PGW-C network element determines that the terminal is a member of the VN group and that the terminal supports Ethernet packet transmission under IP type sessions. The PGW-C network element sends a user session establishment request to the PGW-U network element, which includes a Layer 2 forwarding identifier. The PGW-C network element then sends a session establishment response to the terminal, which also includes a Layer 2 forwarding identifier. Based on the Layer 2 forwarding identifier, the PGW-U network element initiates Layer 2 forwarding of Ethernet packets received through IP type sessions, and the terminal initiates the function of transmitting Ethernet packets under IP type sessions, enabling subsequent Ethernet packet transmission within the VN group during sessions.

[0214] After the PGW-C network element, PGW-U network element, and terminal complete the session negotiation regarding Layer 2 forwarding under IP type session, the terminal and PGW-U network element can perform Layer 2 forwarding under IP type session. The specific explanation is as follows.

[0215] In some implementations, such as Figure 5 As shown, the method S400 of this application embodiment may further include steps S490 to S494, which will be described in detail below.

[0216] In step S490, under an IP type session, terminal 1 encapsulates the data to be sent into an Ethernet packet.

[0217] Ethernet packets can include an Ethernet header (or Ethernet frame header) and a payload. The Ethernet header can include the destination MAC address, source MAC address, Ethernet type, VNI (optional), etc.

[0218] In step S491, terminal 1 sends an encapsulated Ethernet packet to the PGW-U network element. That is, the terminal encapsulates the data to be sent via an IP-type session into an Ethernet packet before sending it. Correspondingly, the PGW-U network element receives the Ethernet packet.

[0219] In step S492, the PGW-U network element decapsulates the received Ethernet packet to obtain the initial Ethernet packet and the destination MAC address. The destination MAC address indicates the Layer 2 address of the peer terminal (or destination terminal), and the Ethernet packet received by the PGW-U network element can be information from terminal 1.

[0220] In some embodiments, the Ethernet packets received by the PGW-U network element are information from the VN group to which terminal 1 belongs. For example, the Ethernet packets received by the PGW-U network element can be information about terminal 2 in the VN group to which terminal 1 belongs, or they can be broadcast / multicast information from the 5G LAN.

[0221] In step S493, the PGW-U network element encapsulates the initial Ethernet packet and forwards it according to the destination MAC address. If the destination MAC address indicates terminal 2, the encapsulated Ethernet packet is sent to terminal 2. That is, the PGW-U network element performs Layer 2 forwarding of Ethernet packets received through IP type sessions.

[0222] For example, the PGW-U network element forwards the Ethernet packet to terminal 2 in the 5G VN group. Terminal 2 is a terminal different from terminal 1 among the multiple members of the VN group to which terminal 1 belongs; terminal 2 can be the peer (destination terminal) of terminal 1. As another example, the PGW-U network element forwards the Ethernet protocol packet to the server of the 5G LAN, and the 5G LAN server forwards the Ethernet protocol packet to terminal 2.

[0223] In some embodiments, if the destination MAC address of the Ethernet packet received by the PGW-U network element indicates terminal 1, then the encapsulated Ethernet packet is sent to terminal 1.

[0224] In step S494, terminal 2 processes the received Ethernet protocol messages.

[0225] The terminal processes packets received through an IP-type session as Ethernet packets. If the terminal is a communication endpoint, it decapsulates and recapsulates packets received through that IP-type session as Ethernet packets; if the terminal is a bridging node (such as a CPE), based on the MAC address table, it can directly forward Ethernet packets received through that IP-type session.

[0226] In some implementations, the step S491 above, where the terminal encapsulates the data to be sent via an IP type session into an Ethernet packet before sending it, may include: the terminal encapsulating the data to be sent via an IP type session into an Ethernet packet and sending the Ethernet packet encapsulated based on the Packet Data Convergence Protocol (PDCP). Step S494, processing the packets received through the session as Ethernet packets, may include: decapsulating the packets received through the session based on PDCP; the received packets are information from the VN group to which the terminal belongs.

[0227] The PGW-U network element's Layer 2 forwarding of Ethernet packets received through IP-type sessions in steps S492 to S493 can include: decapsulating the Ethernet packets received through the session based on GTPU to obtain the initial Ethernet packet and destination MAC address; encapsulating the initial Ethernet packet based on GTPU; and forwarding it according to the destination MAC address. GTPU is the N3 interface protocol, i.e., the protocol between the RAN and user plane network elements.

[0228] The terminal encapsulates Ethernet packets based on the PDCP protocol and sends them. Layer 2 packets are transmitted based on the GTPU tunnel. The PGW-U network element forwards Ethernet packets received through IP type sessions based on GTPU. There are fewer encapsulation and decapsulation operations for Ethernet packets and less auxiliary data is transmitted.

[0229] For example, taking a CPE as an example, the CPE is mainly used to convert the 4G / 5G network or wired broadband signal provided by the operator into a WiFi signal, so that the terminal can access the network, that is, to realize the connection between the terminal and the network side through the WiFi signal.

[0230] like Figure 6 As shown, for the RAN, the protocols in the left column are downlink protocols, and the protocols in the right column are uplink protocols. CPE and PGW-U network elements forward according to Layer 2. Specifically, for uplink packets: the CPE can encapsulate the Ethernet packet to be sent with PDCP, adding a PDCP header to the initial Ethernet packet. The RAN (eNB) and PGW-U network elements have a GTPU tunnel. The RAN decapsulates the received packet, removes the PDCP header, adds a GTPU header, and then sends it through the GTPU tunnel. Intermediate network elements, such as SGW-U network elements, forward according to the GTPU tunnel, unaware of whether the inner packet is in IP or Ethernet format. The PGW-U network element decapsulates the received packet using the GTPU protocol to obtain the initial Ethernet packet and the destination MAC address. Based on the destination MAC address, it performs Layer 2 forwarding. For example, this Ethernet packet is forwarded to terminal 2 within the 5G VN group.

[0231] Downlink packets: PGW-U network elements can encapsulate forwarded Ethernet packets using the GTPU protocol. The Ethernet packet to be forwarded can be information from another terminal within the VN group. During GTPU tunnel transmission, intermediate network elements such as SGW-U network elements forward packets according to the tunnel protocol, unaware of whether the inner packet is in IP or Ethernet format. The RAN decapsulates the received packet, removes the GTPU header, adds a PDCP header, and then forwards it to the CPE. The CPE decapsulates the received packet using the PDCP protocol to obtain the Ethernet packet; alternatively, the CPE forwards the received packet.

[0232] In some implementations, step S491, where the terminal encapsulates the data to be sent via the IP type session into an Ethernet packet before sending it, may include: the terminal encapsulating the data to be sent via the session into an Ethernet packet and sending the Ethernet packet encapsulated based on the first communication protocol. Step S494, processing the packets received via the session as Ethernet packets, may include: decapsulating the packets received via the session based on the first communication protocol; the received packets are information from the VN group to which the terminal belongs. The first communication protocol includes: a network layer network protocol, a VXLAN protocol, and a PDCP protocol. The network layer network protocol may include IP, UDP, etc., and the IP protocol may be IPv4, IPv6, etc. The packet encapsulation order from the inside out is PDCP protocol, network layer network protocol, and VXLAN protocol.

[0233] The PGW-U network element's Layer 2 forwarding of Ethernet packets received through IP-type sessions in steps S492 and S493 can include: decapsulating the Ethernet packets received through the session based on a second communication protocol to obtain the initial Ethernet packet and destination MAC address; encapsulating the initial Ethernet packet based on the second communication protocol; and forwarding it according to the destination MAC address. The second communication protocol includes: network layer network protocols, VXLAN protocol, and GTPU protocol.

[0234] The terminal encapsulates Ethernet packets based on the first communication protocol and sends them. The PGW-U network element forwards the Ethernet packets received through the IP-type session using the second communication protocol at Layer 2. During packet transmission, if an intermediate network element checks and confirms that the packet transmission meets the requirements of the IP-type session, normal communication is guaranteed. It should be noted that before packet transmission, the session establishment response message received by the terminal includes: a Layer 2 forwarding identifier, the IP information of the PGW-U network element's VTEP, and the terminal's corresponding VNI. This data transmission method corresponds to the technical solution described above where the session establishment response message includes a Layer 2 forwarding identifier, the IP information of the PGW-U network element's VTEP, and the terminal's corresponding VNI.

[0235] Taking the first communication protocol, which includes IP and VXLAN protocols, and the terminal as a CPE, as an example. Figure 7As shown, for the RAN, the protocols in the left column are downlink protocols, and the protocols in the right column are uplink protocols. CPE and PGW-U network elements add IP / UDP and VXLAN encapsulation, simulating Layer 3 forwarding. Specifically, for uplink packets: the CPE can encapsulate the Ethernet packet to be sent with PDCP, IP / UDP, and VXLAN, adding VXLAN header, UDP header, IP header, and PDCP header sequentially from the inside out. The VXLAN header may include, but is not limited to, VNI, which can be used to distinguish whether the packet belongs to different VN groups. There is a GTPU tunnel between the RAN and PGW-U network elements. The RAN decapsulates the received packet, removes the PDCP header, adds a GTPU header, leaving the internal IP, UDP, and VXLAN headers unchanged, and then sends it through the GTPU tunnel. Intermediate network elements such as SGW-U are unaware of whether the inner packet is in IP or Ethernet format. The PGW-U network element decapsulates the received packet, removing the GTPU, IP, UDP, and VXLAN headers to obtain the initial Ethernet packet and destination MAC address. Based on the destination MAC address, perform Layer 2 forwarding. For example, forward this Ethernet packet to Terminal 2 within the 5G VN group.

[0236] Downlink packets: PGW-U network elements can encapsulate forwarded Ethernet packets using GTPU, IP / UDP, and VXLAN protocols, adding VXLAN, UDP, IP, and GTPU headers in sequence. The Ethernet packet to be forwarded can be information from another terminal within the 5G VN group. During transmission, intermediate network elements such as SGW-U network elements forward packets via tunnels, unaware of whether the inner packet is in IP or Ethernet format. The RAN decapsulates the received packet, removing the GTPU header and adding a PDCP header, while leaving the internal UDP, IP, and VXLAN headers unchanged, before forwarding it to the CPE. The CPE decapsulates the received packet using PDCP, IP / UDP, and VXLAN protocols to obtain the Ethernet packet; alternatively, the CPE forwards the received packet.

[0237] The previous section introduced the communication method for Ethernet packet forwarding when a terminal accesses a 5G VN group using an IP-type session in a 4G network. The following section explains the communication method for Ethernet packet forwarding when a terminal accesses a VN group using an IP-type session in a 5G network.

[0238] The following is combined with Figure 3 , Figure 8 The communication method S800 in the embodiments of this application will be described in detail. In the core network of a 5G network, the control plane network element can be an SMF network element, and the user plane network element can be a UPF network element. Figure 8 The communication method S800 shown can mainly include steps S830 to S880, which are described in detail below.

[0239] In step S830, the UPF network element receives a session establishment request message initiated by the terminal, which is an IP type session.

[0240] The session establishment request message includes PDU session type information and the terminal's identifier. The terminal's identifier can include at least one of the following: DNN, GPSI, or SUPI. For details on the same technical terms such as identifier, please refer to the preceding description.

[0241] Specifically, step S830 may include multiple sub-steps, such as steps S831 to S832.

[0242] In step S831, the terminal sends a PDU session establishment request (PDUestablishment request) to the AMF network element. Correspondingly, the AMF network element receives the PDU session establishment request.

[0243] In step S832, the AMF network element sends a PDU session generation context request (Nsmf_PDUSession_CreateSMContext Req) to the SMF network element. Correspondingly, the SMF network element receives the session generation context request.

[0244] In step S850, the SMF network element obtains the subscription information of the VN group corresponding to the terminal. The subscription information of the VN group includes the identifier of the VN group (VN Group ID).

[0245] The subscription information for a 5G VN group typically includes: the VN group identifier, the VN group member list, the VN group communication policy, and the VN group data network characteristics. The VN Group ID is associated with the network resources, policies, and configurations defined for that VN group. Multiple VN groups usually exist in a 5G network, each corresponding to a different VN Group ID. The SMF network element obtains the subscription information of the 5G VN group corresponding to the terminal in order to retrieve information such as the VN group identifier and communication policy.

[0246] VN group subscription information is typically stored in UDM or AAA network elements. When a terminal establishes a PDU session, the SMF network element needs to query this information to verify whether the terminal can join a certain VN group and to determine the attributes and policies of that VN group.

[0247] In step S860, the SMF network element creates a group session corresponding to the VN group based on the subscription information of the VN group. This group session corresponds to the VN group to which the terminal belongs. One VN group corresponds to one 5G LAN, and each VN group has a unique VN group identifier.

[0248] This group session has a corresponding identifier for the VN group, and different group sessions can be distinguished by the VN group identifier. Before a terminal joins a VN group for intra-group communication, it needs to create the group session corresponding to the VN group.

[0249] In some implementations, creating the group session corresponding to the VN group in step S860 may specifically include steps S863 to S864.

[0250] In step S863, the SMF network element initiates a PFCP group session establishment request (SessionEstablishment request) to the UPF network element. The group session establishment request includes some or all of the information from the VN group's subscription information. For example, the group session establishment request includes the VN group's identifier, which corresponds to the group session. Accordingly, the UPF network element receives the group session establishment request.

[0251] In step S864, the UPF network element sends a PFCP group session establishment response message (SessionEstablishment rsp) to the SMF network element.

[0252] The PFCP group session response message may include: the IP information of the VTEP of the UPF network element and the VNI corresponding to the terminal. The IP information and VNI of the VTEP of the UPF network element are used to configure the tunnel of the VN group, which is used for the transmission of Ethernet packets between the UPF network element and the terminal. The VNI is used to identify the virtual extended LAN network corresponding to the terminal.

[0253] The creation of group sessions corresponding to VN groups and the specific interaction steps between control plane network elements and user plane network elements have been clarified.

[0254] In step S870, the SMF network element sends a Layer 2 forwarding identifier and a VN group identifier to the UPF network element. The Layer 2 forwarding identifier is used to trigger the UPF network element to perform Layer 2 forwarding of Ethernet packets received under IP type sessions. Alternatively, the Layer 2 forwarding identifier is used to trigger the user plane network element to receive and forward Ethernet packets under IP type sessions. The VN group identifier is used to associate with the group session of the VN group.

[0255] Accordingly, the UPF network element receives the Layer 2 forwarding identifier and the VN group identifier. The UPF network element can perform Layer 2 forwarding of Ethernet packets received through IP type sessions based on the Layer 2 forwarding identifier.

[0256] After creating the PFCP group session corresponding to the VN group, the SMF network element sends the Layer 2 forwarding identifier and the VN group identifier to the UPF network element so that the UPF network element can initiate Layer 2 forwarding of Ethernet packets received under the IP type session.

[0257] UPF network elements can use the identifier of a VN group to allow data transmission between a terminal and other terminals in that VN group, but prohibit intra-group data transmission between a terminal and terminals in other VN groups. For example, if an Ethernet packet sent by a terminal contains a VNI, and the VNI has a mapping relationship with the VN group identifier, the UPF network element can identify the VN group to which the Ethernet packet belongs based on the VNI.

[0258] Optionally, the UPF network element can identify different VN groups based on MAC addresses. A mapping table exists between MAC addresses and VN groups; the VN group to which the terminal belongs can be identified through the source MAC address, and the VN group is marked based on its identifier. Specific methods for identifying and controlling packets within and outside VN groups can be found in the relevant 3GPP specifications, and will not be detailed further.

[0259] In some implementations, sending the Layer 2 forwarding identifier and the VN group identifier to the UPF network element in step S870 may specifically include steps S871 to S872.

[0260] In step S871, the SMF network element sends a PFCP user session establishment request (SessionEstablishment req) to the UPF network element. The PFCP user session establishment request includes a Layer 2 forwarding identifier and a VN group identifier. The PFCP user session can be associated with the group session to which the terminal belongs based on the VN group identifier. Accordingly, the UPF network element receives the PFCP user session establishment request.

[0261] Optionally, the PFCP user session establishment request may also include: the requesting IP address of the terminal user. The IP address is the logical identifier of the terminal in the DN, and the user's requesting IP address is associated with the forwarding policy of the VN group.

[0262] In step S872, the UPF network element sends a PFCP user session establishment response (Session Establishmentreq), and correspondingly, the SMF network element receives the PFCP user session establishment response.

[0263] The UPF network element, based on the Layer 2 forwarding identifier and the VN group identifier, performs the relevant configuration for Layer 2 packet forwarding under IP type sessions, and sends a PFCP user session establishment response message to the SMF network element to indicate the result of the user session establishment. The specific interaction steps between the control plane network element and the user plane network element for creating a PFCP user session are clarified.

[0264] In step S880, the SMF network element sends a session establishment response message to the terminal. This message includes a Layer 2 forwarding identifier, which is also used to trigger the terminal to process packets received through the IP type session as Ethernet packets, or to encapsulate data to be sent through the IP type session into Ethernet packets before sending. In other words, it triggers the terminal to receive or send Ethernet packets under an IP type session.

[0265] The aforementioned terminal processes the packets received through the IP type session as Ethernet packets, which may include: if the terminal is a communication endpoint, the terminal decapsulates the packets received through the IP type session as Ethernet packets; if the terminal is a bridging node (such as CPE) or gateway, based on the MAC address table, the terminal can directly forward the Ethernet packets received through the IP type session.

[0266] The session establishment response message can carry a PCO. For example, the PCO can be extended to carry a Layer 2 forwarding identifier.

[0267] In some implementations, the session establishment response information (or in the PCO) may carry: a Layer 2 forwarding identifier, the IP information of the VTEP of the UPF network element, and the VNI corresponding to the terminal. The IP information of the VTEP of the UPF network element is used to configure the tunnel of the VN group, and the tunnel of the VN group is used for the transmission of Ethernet packets between the UPF network element and the terminal. The VNI is used to identify the VXLAN network corresponding to the terminal. In VXLAN encapsulation, the VXLAN header of the packet contains the VNI characters to distinguish different virtual network groups.

[0268] The session establishment response message sent to the terminal includes the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal. It is used to configure the tunnel of the VN group on the terminal side so that Ethernet packets can be transmitted based on the tunnel in the future.

[0269] Specifically, the process of sending the response information for establishing the PDN session in step S880 may include steps S881 to S882.

[0270] In step S881, the SMF network element sends a PDU session establishment response message to the AMF network element. This response message may carry a PCO, and the PCO may carry a Layer 2 forwarding identifier. Correspondingly, the AMF network element receives the PDU session establishment response message.

[0271] In step S882, the AMF network element sends a PDU session establishment accept to the terminal. This session establishment accept may carry a PCO, which may carry a Layer 2 forwarding identifier. Accordingly, the terminal receives the PDU session establishment accept.

[0272] Optionally, the PCO may carry: a Layer 2 forwarding identifier, the IP information of the VTEP of the UPF network element, and the VNI corresponding to the terminal.

[0273] The terminal has the capability to forward Layer 2 packets under IP session type. Upon receiving the Layer 2 forwarding identifier, it initiates the Layer 2 packet forwarding function under IP session type. This facilitates the timely activation of the Layer 2 packet forwarding function under IP session type according to application requirements.

[0274] In some implementations, the session establishment response information may not include the Layer 2 forwarding identifier. The terminal can pre-configure the Layer 2 forwarding identifier, that is, pre-enable the function of encapsulating data to be sent into Ethernet packets before sending under IP-type sessions, or the function of processing packets received through IP-type sessions as Ethernet packets. In other words, the Layer 2 forwarding function under IP-type sessions is kept always on. Based on the pre-configured Layer 2 forwarding identifier, the terminal can encapsulate data to be sent through IP-type sessions into Ethernet packets before sending, or process packets received through IP-type sessions as Ethernet packets. This helps reduce the configuration of the Layer 2 forwarding identifier in the session establishment response information sent by SMF network elements, thus reducing the amount of information in the session establishment response information.

[0275] Optionally, the terminal side can pre-configure the Layer 2 forwarding identifier, the IP information of the VTEP of the UPF network element, and the VNI corresponding to the terminal.

[0276] Through steps S870 and S880, the UPF network element starts the function of forwarding Ethernet packets received under IP type sessions at Layer 2, and the terminal starts receiving or sending Ethernet packets under IP type sessions.

[0277] In this embodiment, the SMF network element obtains the subscription information of the VN group corresponding to the terminal, and creates a group session corresponding to the VN group based on the subscription information. It sends a Layer 2 forwarding identifier and the VN group identifier to the UPF network element to trigger the UPF network element to perform Layer 2 forwarding of Ethernet packets received under the IP type session. The SMF network element sends a session establishment response message including the Layer 2 forwarding identifier to the terminal to trigger the terminal to process packets received through the session as Ethernet packets, or to encapsulate data to be sent through the session into Ethernet packets before sending. This embodiment helps the terminal access the 5G network using an IP type session and perform Layer 2 transmission with other terminals within the 5G VN group, accessing N6-side services in a Layer 2 manner. It also helps the terminal maintain uninterrupted service during 4G / 5G network handover scenarios based on Layer 2 forwarding.

[0278] In some implementations, before receiving the session establishment request information from the receiving terminal in step S830, the method S800 of this application embodiment may further include steps S810 to S820.

[0279] In step S810, the SMF network element configures a preset identifier set. The preset identifier set may include multiple feature identifiers, and the terminal corresponding to any of the multiple feature identifiers supports the transmission of Ethernet packets under IP type sessions.

[0280] The preset identifier set can be a collection of feature identifiers corresponding to multiple terminals in a VN group. Alternatively, it can be a collection of feature identifiers corresponding to multiple terminals in multiple VNs. The SMF network element pre-configures the preset identifier set so that, in subsequent processes, it can identify whether a terminal supports transmitting Ethernet packets under IP type sessions based on the terminal's feature identifiers.

[0281] In step S811, the UDM network element pre-configures the user's subscription information.

[0282] For example, for a 5G network, a user's subscription information may include: APN / DNN is APN1, PDU session type is IP type or ethernet type, and VN group is **cde.

[0283] In step S820, the terminal completes the user registration process. The general registration and network access process for terminals can be found in the relevant 3GPP technical specifications, and will not be detailed further.

[0284] In some implementations, obtaining the subscription information of the VN group corresponding to the terminal in step S850 above may include: the SMF network element obtaining the identifier of the shared VN group data corresponding to the terminal; and obtaining the subscription information of the VN group corresponding to the terminal based on the identifier of the shared VN group data. Alternatively, before obtaining the subscription information of the VN group corresponding to the terminal in step S850, the method of this application embodiment may further include step S840.

[0285] In step S840, the SMF network element obtains the identifier (shareVnGroupDataIds) of the shared VN group data corresponding to the terminal.

[0286] The terminal can obtain the user's 5G subscription information from the UDM network element. The user's 5G subscription information may include information such as shareVnGroupDataIds, and there is a mapping relationship between VN Group ID and shareVnGroupDataIds. When the terminal establishes a PDU session, it needs to query this information to verify whether the terminal can join a certain VN group.

[0287] Optionally, obtaining the identifier of the shared VN group data corresponding to the user in step S840 may include: obtaining the user's 5G subscription information, whereby the user's 5G subscription information includes the identifier of the shared VN group data corresponding to the user. Specifically, the process of obtaining the user's 5G subscription information (or step S840) may include steps S841 to S842.

[0288] In step S841, the SMF network element sends a request message (Nudm_SDM_GetUESession managementSubscriptionData_Request) to the UDM network element to obtain the user's 5G subscription information. This request information may include SUPI, PLMN, singleNssai, and DNN standard information elements.

[0289] Among them, IMSI is used to uniquely identify a user (Subscriber), PLMN is used to specify the operator network where the current user is located, and singleNssai is used to specify the network slice associated with the request (single network slice selection assistance info, S-NSSAI).

[0290] In step S842, the UDM network element sends a response message (Nudm_SDM_GetUESession managementSubscriptionData_Response) to the SMF network element to obtain the terminal subscription information, i.e., returns the user's 5G subscription information. The user's 5G subscription information may include: the subscribed PDU type and the identifier of the shared VN group data. The PDU type can be Ethernet or IP. The identifier of the shared VN group data is used to obtain the subscription information of the VN group corresponding to the terminal, and there is a mapping relationship between the identifier of the shared VN group data and the identifier of the VN group.

[0291] In some implementations, obtaining the subscription information of the VN group corresponding to the terminal in step S850 may include: the SMF network element receiving the subscription information of the VN group from the UDM network element; or, receiving the subscription information of the VN group from the AAA network element.

[0292] The subscription information for 5G VN groups is stored in the UDM network element and can be obtained from the UDM network element; the subscription information for 5G VN groups is stored in the AAA network element and can be obtained from the AAA network element.

[0293] Optionally, the SMF network element receives VN group subscription information from the UDM network element. Specifically, this may include: the SMF network element sending a VN group subscription information request message to the UDM network element, the VN group subscription information request message including an identifier for shared VN group data. After receiving the VN group subscription information request message, the UDM network element finds the VN group subscription information corresponding to the identifier of the shared VN group data and sends the VN group subscription information corresponding to the terminal to the SMF network element. Correspondingly, the SMF network element receives the VN group subscription information corresponding to the terminal. That is, the SMF network element obtains the 5G VN group subscription information from the UDM network element through the identifier of the shared VN group data.

[0294] Optionally, the SMF network element receives the VN group subscription information sent by the AAA network element. Specifically, this may include: the SMF network element sending a request message for VN group subscription information to the AAA network element, which includes SUPI and APN. After receiving the VN group subscription information request message, the AAA network element sends the user's subscription information corresponding to the terminal to the SMF network element according to the SUPI and APN in the request message. The user's subscription information includes the VN group subscription information. Correspondingly, the SMF network element receives the VN group subscription information corresponding to the terminal. For example, during session establishment, the SMF network element sends an AccessRequest message (i.e., a request message for VN group subscription information) to the AAA network element, and the AAA network element can return the 5G VN group subscription information in the response message.

[0295] The session establishment request message received by the SMF network element includes the terminal's identifier. The SMF network element can determine whether the terminal supports Ethernet packet forwarding under IP type sessions based on the terminal's identifier.

[0296] In some implementations, step S860, which involves creating a group session corresponding to a VN group based on the VN group's subscription information, may include: if it is determined that the terminal's feature identifier matches a feature identifier in a preset identifier set, then creating a group session corresponding to the VN group based on the VN group's subscription information. Wherein, any terminal corresponding to any feature identifier in the preset identifier set supports transmitting Ethernet packets under IP type sessions.

[0297] After identifying that the terminal supports the transmission of Ethernet packets under IP type sessions, the group session corresponding to the VN group is created. For terminals that do not support Layer 2 forwarding, the SMF network element is prevented from sending invalid group session creation request signaling to the UPF network element, thereby reducing the amount of data exchanged by the signaling.

[0298] Optionally, before creating the group session corresponding to the VN group in step S860, or before the SMF network element initiates a request to the UPF network element to establish a PFCP group session in step S863, the method S800 of this application embodiment may further include step S861.

[0299] In step S861, it is determined that the feature identifier of the terminal matches a feature identifier in a preset identifier set.

[0300] The system compares the terminal's characteristic identifier with a preset identifier set to determine whether the terminal supports transmitting Ethernet packets under IP type sessions. For terminals that do not support Layer 2 forwarding, it avoids the SMF network element sending invalid group session creation request signaling to the UPF network element.

[0301] Through steps S810 to S880, the SMF network element completes session negotiation with the UPF network element and the terminal, respectively. Specifically, the SMF network element determines that the terminal is a member of the VN group and that the terminal supports Ethernet packet transmission under IP type sessions. The SMF network element sends a user session establishment request to the UPF network element, which includes a Layer 2 forwarding identifier. The SMF network element sends a session establishment response to the terminal, which also includes a Layer 2 forwarding identifier. Based on the Layer 2 forwarding identifier, the UPF network element initiates Layer 2 forwarding of Ethernet packets received through IP type sessions, and the terminal initiates the function of transmitting Ethernet packets under IP type sessions, enabling subsequent Ethernet packet transmission within the VN group during sessions.

[0302] After the SMF network element, UPF network element, and terminal complete the session negotiation regarding Layer 2 forwarding of IP type sessions, the terminal and UPF network element can perform Layer 2 packet forwarding under IP type sessions. The specific explanation is as follows.

[0303] In some implementations, the method S800 of this application embodiment may further include steps S890 to S894, which will be described in detail below.

[0304] In step S890, under an IP type session, the terminal encapsulates the data to be sent into an Ethernet packet.

[0305] Ethernet packets can include an Ethernet header (Ethernet frame header) and a payload. The Ethernet frame header can include: destination MAC address, source MAC address, Ethernet type, VNI (optional), etc.

[0306] In step S891, the terminal sends an encapsulated Ethernet packet to the UPF network element. That is, the terminal encapsulates the data to be sent via an IP-type session into an Ethernet packet before sending it. Correspondingly, the UPF network element receives the Ethernet packet.

[0307] In step S892, the UPF network element decapsulates the received Ethernet packet to obtain the initial Ethernet packet and the destination MAC address. The destination MAC address indicates the Layer 2 address of the peer terminal, and the Ethernet packet received by the UPF network element is information from the VN group to which the terminal belongs.

[0308] In some embodiments, the Ethernet packets received by the UPF network element may also be information about another terminal in the VN group to which the terminal belongs, or broadcast / multicast information of the VN group.

[0309] In step S893, the UPF network element encapsulates the initial Ethernet packet and forwards it according to the destination MAC address. If the destination MAC address indicates UE2, the encapsulated Ethernet packet is sent to UE2. That is, the PGW-U network element performs Layer 2 forwarding of Ethernet packets received through IP type sessions.

[0310] In some embodiments, if the destination MAC address of the Ethernet packet received by the UPF network element indicates the terminal, then the encapsulated Ethernet packet is sent to the terminal.

[0311] In step S894, the terminal processes the received Ethernet protocol messages.

[0312] The terminal processes packets received through an IP-type session as Ethernet packets. If the terminal is a communication endpoint, it decapsulates and recapsulates packets received through that IP-type session as Ethernet packets; if the terminal is a bridging node (such as a CPE), based on the MAC address table, it can directly forward Ethernet packets received through that IP-type session.

[0313] In some implementations, the step S891 above, where the terminal encapsulates the data to be sent through the session into an Ethernet packet before sending it, may include: the terminal encapsulating the data to be sent through an IP-type session into an Ethernet packet and sending the PDCP-encapsulated Ethernet packet. Step S894, where the terminal processes the packets received through the session as Ethernet packets, may include: the terminal decapsulating the packets received through the session based on the PDCP protocol; the received packets are information from the VN group to which the terminal belongs.

[0314] The UPF network element in steps S892 to S893 above performs Layer 2 forwarding of Ethernet packets received through IP type sessions, which may include: the UPF network element decapsulates the Ethernet packets received through the session based on the GTPU protocol to obtain the initial Ethernet packet and the destination MAC address, encapsulates the initial Ethernet packet based on the GTPU protocol, and forwards it according to the destination MAC address.

[0315] The terminal sends Ethernet packets encapsulated with PDCP. The UPF network element performs Layer 2 forwarding of the Ethernet packets received through the IP type session based on GTPU. There are fewer encapsulation and decapsulation operations for the Ethernet packets and less auxiliary data is transmitted.

[0316] Taking the terminal as a CPE as an example. Figure 6 As shown, for the RAN, the protocols in the left column are downlink protocols, and the protocols in the right column are uplink protocols. CPE and UPF network elements forward according to Layer 2. Specifically, for uplink packets: the CPE can encapsulate the Ethernet packet to be sent with PDCP, adding a PDCP header to the initial Ethernet packet. There is a GTPU tunnel between the RAN (such as gNB) and the UPF network elements. The RAN decapsulates the received packet, removes the PDCP header, adds a GTPU header, and then sends it through the GTPU tunnel. Intermediate network elements, such as I-UPF network elements, forward according to the GTPU tunnel, unaware of whether the inner packet is in IP or Ethernet format. The UPF network element decapsulates the received packet using the GTPU protocol to obtain the initial Ethernet packet and the destination MAC address. Based on the destination MAC address, it performs Layer 2 forwarding. For example, this Ethernet packet is forwarded to terminal 2 within the 5G VN group.

[0317] Downlink packets: UPF network elements can encapsulate forwarded Ethernet packets using the GTPU protocol. The Ethernet packet to be forwarded can be information sent from another terminal within the VN group. During transmission through the GTPU tunnel, intermediate network elements such as I-UPF network elements forward packets according to the tunnel protocol, unaware of whether the inner packet is in IP or Ethernet format. The RAN decapsulates the received packet, removes the GTPU header, adds a PDCP header, and then forwards it to the CPE. The CPE decapsulates the received packet using the PDCP protocol to obtain the Ethernet packet; alternatively, the CPE forwards the received packet.

[0318] In other implementations, the process of the terminal encapsulating the data to be sent through the session into Ethernet packets in steps S890 to S891 can include: the terminal encapsulating the data to be sent through an IP-type session into Ethernet packets and sending the Ethernet packets encapsulated based on the first communication protocol. The processing of packets received through the session as Ethernet packets in step S894 can include: decapsulating the packets received through the session based on the first communication protocol; the received packets are information from the VN group to which the terminal belongs. The first communication protocol includes: network layer network protocol, VXLAN protocol, and PDCP protocol. The network layer network protocol can include IP, UDP, etc., and the IP protocol can be IPv4, IPv6, etc. The encapsulation order of the packets from the inside out is PDCP protocol, network layer network protocol, and VXLAN protocol.

[0319] The UPF network element in steps S892 to S893 above performs Layer 2 forwarding of Ethernet packets received through IP type sessions, which may include: decapsulating the Ethernet packets received through the session based on a second communication protocol to obtain the initial Ethernet packet and the destination Media Access Control (MAC) address; encapsulating the initial Ethernet packet based on the second communication protocol; and forwarding it according to the destination MAC address. The second communication protocol includes: network layer network protocols, VXLAN protocol, and GTPU protocol.

[0320] The terminal sends Ethernet packets encapsulated based on the first communication protocol. The UPF network element forwards the Ethernet packets received through the IP type session at Layer 2 based on the second communication protocol. If the intermediate network element checks the packet format, it can meet the IP packet transmission requirements under the IP type session. It should be noted that this data transmission method corresponds to the technical solution described above for the session establishment response message, which includes the Layer 2 forwarding identifier, the IP information of the UPF network element's VTEP, and the VNI corresponding to the terminal.

[0321] Taking the first communication protocol, which includes IP and VXLAN protocols, and the terminal as a CPE, as an example. Figure 7 As shown, for the RAN, the protocols in the left column are downlink protocols, and the protocols in the right column are uplink protocols. CPE and UPF network elements add IP / UDP and VXLAN encapsulation, simulating Layer 3 forwarding. Specifically, for uplink packets: the CPE can encapsulate the Ethernet packet to be sent with PDCP, IP / UDP, and VXLAN, adding VXLAN header, UDP header, IP header, and PDCP header sequentially from the inside out. The VXLAN header may include, but is not limited to, VNI, which can be used to distinguish whether the packet belongs to different VN groups. There is a GTPU tunnel between the RAN and UPF network elements. The RAN decapsulates the received packet, removes the PDCP header, adds a GTPU header, leaving the internal VXLAN, UDP, and IP headers unchanged, and then sends it through the GTPU tunnel. Intermediate network elements such as I-UPF are unaware of whether the inner packet is in IP or Ethernet format. The UPF network element decapsulates the received packet with VXLAN, IP / UDP, and GTPU, removing the GTPU header, IP header, UDP header, and VXLAN header to obtain the initial Ethernet packet and destination MAC address. Based on the destination MAC address, perform Layer 2 forwarding. For example, forward this Ethernet packet to Terminal 2 within the 5G VN group.

[0322] Downlink packets: PGW-U network elements can encapsulate forwarded Ethernet packets using GTPU, IP / UDP, and VXLAN protocols, adding VXLAN, UDP, IP, and GTPU headers in sequence. The Ethernet packet to be forwarded can be information sent from another terminal within the 5G VN group. During tunnel transmission, intermediate network elements such as SGW-U network elements forward packets according to tunnel protocols, unaware of whether the inner packet is in IP or Ethernet format. The RAN decapsulates the received packet, removes the GTPU header, adds a PDCP header, leaving the internal IP, UDP, and VXLAN headers unchanged, and then forwards it to the CPE. The CPE decapsulates the received packet using PDCP, IP / UDP, and VXLAN protocols to obtain the Ethernet packet; alternatively, the CPE forwards the received packet.

[0323] The preceding text introduced a communication method for layer 2 forwarding of terminal access to VN groups via IP-type sessions in 4G and 5G networks. The following describes the application of embodiments of this application in access network handover scenarios.

[0324] Figure 9 This refers to a 4G network access network handover scenario. For example... Figure 9 As shown, in the 4G access network handover scenario, the communication method of this application embodiment may further include steps S910 to S950, which will be described in detail below.

[0325] In step S910, the terminal accesses the 4G RAN and establishes a PDN session. For detailed implementation information, please refer to the above text. Figure 4 As shown.

[0326] If the handover is within the 4G network, i.e., both the source RAN (S-RAN) and the destination RAN (T-RAN) are 4G base stations, then proceed to step S920.

[0327] In step S920, the source RAN is switched to the destination RAN. The process for switching from the source RAN to the destination RAN is the same as the 3GPP standard process and will not be described in detail here.

[0328] It should be noted that the control plane anchor point PGW-C and data plane anchor point PGW-U for the terminal must remain unchanged. This ensures that the PGW-U's support for Layer 2 forwarding under IP type sessions remains unchanged, and the terminal's support for receiving / sending Ethernet packets under IP type sessions remains unchanged. If the control plane anchor point PGW-C or the data plane anchor point PGW-U for the terminal changes, then it is necessary to... Figure 4 The method shown involves accessing the VN group through the destination RAN, which may cause interruptions to Layer 2 forwarding services.

[0329] In step S930, the PGW-C network element sends a session modification request (N4 SessionModification req) to the PGW-U network element. Correspondingly, the PGW-U network element receives the session modification request, sends a session modification response to the PGW-C network element, and updates the data plane tunnel information. The N4 session modification process can be referenced from the 3GPP standard process and will not be detailed further.

[0330] If the terminal switches from a 4G network to a 5G network, that is, the source RAN is a 4G base station and the destination RAN is a 5G base station, then proceed to step S940.

[0331] In step S940, the source RAN is switched to the destination RAN. The process of switching from 4G source RAN to 5G destination RAN can refer to the 3GPP standard process and will not be described in detail here.

[0332] It should be noted that the control plane anchor points PGW-C and SMF network elements corresponding to the terminal must remain unchanged; these PGW-C and SMF network elements can be shared network elements. Similarly, the data plane anchor points PGW-U and UPF network elements must remain unchanged; these PGW-U and UPF network elements can be shared network elements. This ensures that the PGW-U and UPF network elements maintain their support for Layer 2 forwarding under IP type sessions, and that the terminal maintains its support for receiving / sending Ethernet packets under IP type sessions. If the control plane anchor point or data plane anchor point corresponding to the terminal changes, it is necessary to... Figure 8 The method shown accesses the VN group via the 5G destination RAN, which may cause interruptions to Layer 2 forwarding services.

[0333] In step S950, the SMF network element sends a session modification request (N4 Session Modificationreq) to the UPF network element. Correspondingly, the UPF network element receives the session modification request, sends a session modification response to the SMF network element, and updates the data plane tunnel information.

[0334] In this embodiment of the application, in a 4G network, it helps the terminal to access the 5G LAN via IP and conduct L2 communication with other terminal users in the VN group, and access N6 side services via L2. It also helps the terminal maintain uninterrupted L2 forwarding services under IP type sessions in 4G network handover scenarios and 4G / 5G network handover scenarios, thereby improving the user experience.

[0335] Figure 10 This is a scenario for access network handover in 5G networks. For example... Figure 10 As shown, in the 5G access network handover scenario, the communication method of this application embodiment may further include steps S1010 to S1050, which will be described in detail below.

[0336] In step S1010, the terminal accesses the 5G RAN and creates a PDU session. For detailed implementation information, please refer to the description above. Figure 8 .

[0337] If the handover is within the 5G network, meaning both the source RAN and the destination RAN are 5G base stations, then proceed to step S1020.

[0338] In step S1020, the source RAN is switched to the destination RAN. The process for switching from the source RAN to the destination RAN is the same as the 3GPP standard process and will not be described in detail here.

[0339] It should be noted that the control plane anchor point (SMF) and data plane anchor point (UPF) of the terminal must remain unchanged. This ensures that the UPF's support for Layer 2 forwarding under IP type sessions remains unchanged, and the terminal's support for receiving / sending Ethernet packets under IP type sessions remains unchanged. If the control plane anchor point (SMF) or data plane anchor point (UPF) of the terminal changes, it is necessary to... Figure 8 The method shown involves accessing the VN group through the destination RAN, which may cause interruptions to Layer 2 forwarding services.

[0340] In step S1030, the SMF network element sends a session modification request (N4 SessionModification req) to the UPF network element. Correspondingly, the UPF network element receives the session modification request, sends a session modification response to the UPF network element, and updates the data plane tunnel information. The N4 session modification process can be referenced from the 3GPP standard process and will not be detailed further.

[0341] If the terminal switches from a 5G network to a 4G network, that is, the source RAN is a 5G base station and the destination RAN to which it switches is a 4G base station, then proceed to step S1040.

[0342] In step S1040, the source RAN is switched to the destination RAN. The process of switching from 5G source RAN to 4G destination RAN can refer to the 3GPP standard process and will not be described in detail here.

[0343] It should be noted that the control plane anchor points PGW-C and SMF network elements corresponding to the terminal must remain unchanged; these PGW-C and SMF network elements can be shared network elements. Similarly, the data plane anchor points PGW-U and UPF network elements must remain unchanged; these PGW-U and UPF network elements can be shared network elements. This ensures that the PGW-U and UPF network elements maintain their support for Layer 2 forwarding under IP type sessions, and that the terminal maintains its support for receiving / sending Ethernet packets under IP type sessions. If the control plane anchor point or data plane anchor point corresponding to the terminal changes, it is necessary to... Figure 4 The method shown accesses the VN group via the 4G destination RAN, which will cause interruptions to Layer 2 forwarding services.

[0344] In step S1050, the PGW-C network element sends a session modification request (N4 SessionModification req) to the PGW-U network element. Correspondingly, the PGW-U network element receives the session modification request, sends a session modification response to the PGW-C network element, and updates the data plane tunnel information.

[0345] The embodiments of this application help terminals access 5G LAN and other terminal users in the VN group via IP to conduct L2 mutual access and access N6 side services via L2; it also helps terminals maintain uninterrupted L2 forwarding services under IP type sessions in 5G network handover scenarios and 5G / 4G network handover scenarios, thereby improving the user experience.

[0346] The above text combined Figures 1 to 10 The method embodiments of this application are described in detail below, in conjunction with... Figures 11 to 13 The present application provides a detailed description of the apparatus embodiments. It should be understood that the descriptions of the apparatus embodiments correspond to the descriptions of the method embodiments; therefore, any parts not described in detail can be found in the foregoing method embodiments.

[0347] Figure 11 This is a schematic structural diagram of a communication device provided in an embodiment of this application. Figure 11 The communication device 1100 shown can be a control plane network element, which can be a PGW-C or SMF network element, or a combined PGW-C and SMF network element. The communication device 1100 may include: a receiving module 1110, a transmitting module 1120, and a processing module 1130.

[0348] The receiving module 1110 is used to receive a session establishment request message from the terminal, the session being an IP type session; and to obtain the subscription information of the VN group corresponding to the terminal, the subscription information of the VN group including the identifier of the VN group.

[0349] The processing module 1130 is used to create a group session corresponding to the VN group based on the VN group's subscription information.

[0350] The sending module 1120 is used to send a Layer 2 forwarding identifier and a VN group identifier to the user plane network element. The Layer 2 forwarding identifier is used to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets received through the session, and the VN group identifier is used to indicate that the session is a session in a VN group. The sending module 1120 is also used to send a session establishment response message to the terminal. The session establishment response message includes a Layer 2 forwarding identifier, which is used to trigger the terminal to process packets received through the session as Ethernet packets, or to encapsulate data to be sent through the session into Ethernet packets before sending them.

[0351] Optionally, the session establishment request message includes the terminal's feature identifier. The receiving module 1110, used to obtain the identifier of the shared VN group data corresponding to the terminal, may include: obtaining the identifier of the shared VN group data corresponding to the terminal when it is determined that the terminal's feature identifier matches the feature identifier in a preset identifier set, wherein the terminal corresponding to any feature identifier in the preset identifier set supports the transmission of Ethernet packets under IP type session.

[0352] Optionally, the session establishment request message includes the terminal's feature identifier. The receiving module 1110 is configured to create a group session corresponding to the VN group based on the VN group's subscription information, including: if it is determined that the terminal's feature identifier matches a feature identifier in a preset identifier set, creating a group session corresponding to the VN group based on the VN group's subscription information, wherein the terminal corresponding to any feature identifier in the preset identifier set supports transmitting Ethernet packets under IP type sessions.

[0353] Optionally, the processing module 1130 is used to create a group session corresponding to the VN group based on the subscription information of the VN group, including: the notification sending module 1120 sending a PFCP group session establishment request to the user plane network element, the group session establishment request including some or all of the information in the subscription information of the VN group; the control receiving module 1110 receiving the PFCP group session establishment response, the group session establishment response including the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal, the IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the VN group, and the tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

[0354] Optionally, the sending module 1120 is used to send a Layer 2 forwarding identifier and a VN group identifier to the user plane network element, including: sending a PFCP user session establishment request to the user plane network element, wherein the PFCP user session establishment request includes a Layer 2 forwarding identifier and a VN group identifier, and the user session is associated with a group session; and receiving a PFCP user session establishment response.

[0355] Optionally, the session establishment response message may also include: the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal. The IP information and VNI of the VTEP of the user plane network element are used to configure the tunnel of the VN group. The tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

[0356] Optionally, the receiving module 1110 is used to obtain the subscription information of the VN group corresponding to the terminal, including: receiving the subscription information of the VN group from the UDM network element; or, receiving the subscription information of the VN group from the AAA network element.

[0357] Optionally, the feature identifier may include at least one of the following: DNN, GPSI, or SUPI.

[0358] Optionally, the control plane network element is a PGW-C network element and the user plane network element is a PGW-U network element; or, the control plane network element is an SMF network element and the user plane network element is a UPF network element.

[0359] Figure 11 The communication device 1100 shown can also be a terminal, a chip in the terminal (such as a modem chip, or a SoC chip or SIP chip containing a modem core), or a logic module or software that can implement all or part of the terminal.

[0360] When the communication device 1100 is a terminal, it includes two technical solutions. In the first technical solution, the sending module 1120 is used to send a session establishment request message, which is an IP type session. The receiving module 1110 is used to receive a session establishment response message, which includes a Layer 2 forwarding identifier. The processing module 1130 is used to process the packets received through the session as Ethernet packets based on the Layer 2 forwarding identifier, or to encapsulate the data to be sent through the session into Ethernet packets before sending them.

[0361] Optionally, the session establishment response message may also include: the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal. The IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the VN group to which the terminal belongs. The tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

[0362] In the second technical solution, the sending module 1120 is used to send a session establishment request message, where the session is an IP type session. The receiving module 1110 is used to receive a session establishment response message. The processing module 1130 is used to encapsulate the data to be sent through the session into Ethernet packets based on a pre-configured Layer 2 forwarding identifier before sending it, or to process packets received through the session as Ethernet packets.

[0363] In any of the above technical solutions of the terminal, optionally, the processing module 1130 is used to process the packets received through the session as Ethernet packets based on the Layer 2 forwarding identifier, or to encapsulate the data to be sent through the session into Ethernet packets and then send them, including: encapsulating the data to be sent through the session into Ethernet packets and sending the Ethernet packets encapsulated based on PDCP; or, decapsulating the packets received through the session based on PDCP, wherein the received packets are information from the VN group to which the terminal belongs.

[0364] Optionally, the processing module 1130 is used to process the packets received through the session as Ethernet packets based on the Layer 2 forwarding identifier, or to encapsulate the data to be sent through the session into Ethernet packets before sending them, including: encapsulating the data to be sent through the session into Ethernet packets and sending the Ethernet packets encapsulated based on the first communication protocol; or, decapsulating the packets received through the session based on the first communication protocol, wherein the received packets are information from the VN group to which the terminal belongs; the first communication protocol includes: network layer network protocol, VXLAN protocol, and PDCP.

[0365] Figure 12 This is a schematic structural diagram of a communication device provided in another embodiment of this application. Figure 12 The dashed lines indicate that the unit or module is optional. The communication device 1200 can be used to implement the method described in the above method embodiments. The communication device 1200 can be a chip or a communication device. The communication device 1200 can be a control plane network element, which can be a PGW-C network element, an SMF network element, or a combined PGW-C and SMF network element. The communication device 1200 can also be a terminal.

[0366] The communication device 1200 may include one or more processors 1210. The processor 1210 may support the communication device 1200 in implementing the methods described in the preceding method embodiments. The processor 1210 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may also be other general-purpose processors, microprocessor units (MPUs), microcontroller units (MCUs), graphics processing units (GPUs), artificial intelligence processors (AI processors) or neural processing units (NPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0367] The communication device 1200 may further include one or more memories 1220. The memories 1220 store a program that can be executed by the processor 1210, causing the communication device 1200 to perform the methods described in the preceding method embodiments. The memories 1220 may be independent of the processor 1210 or integrated into the processor 1210.

[0368] In this embodiment, the memory 1220 may include, but is not limited to, a cache, a read-only memory (ROM), a random access memory (RAM), a synchronous dynamic random access memory (SDRAM), a hard disk drive (HDD) or a solid-state drive (SSD), an erasable programmable read-only memory (EPROM), or a compact disc read-only memory (CD-ROM), etc.

[0369] The communication device 1200 may also include a transceiver 1230. The processor 1210 can communicate with other devices or chips via the transceiver 1230. For example, the processor 1210 can send and receive data with other devices or chips via the transceiver 1230.

[0370] It should be noted that the information interaction and execution process between the above-mentioned devices / units are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, and they will not be repeated here.

[0371] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments 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. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0372] Figure 13 This is a schematic diagram of a communication system provided in an embodiment of this application. The communication system 1300 can be a core network or a communication system including a core network. The communication system 1300 may include: a control plane network element 1310 and a user plane network element 1320.

[0373] Control plane network element 1310 is used to receive a session establishment request message from a terminal, which is an IP type session; obtain the identifier of the shared VN group data corresponding to the terminal; obtain the subscription information of the VN group corresponding to the terminal based on the identifier of the shared VN group data, the subscription information of the VN group includes the identifier of the VN group; create a group session corresponding to the VN group based on the subscription information of the VN group; send a Layer 2 forwarding identifier and the identifier of the VN group to the user plane network element, the Layer 2 forwarding identifier is used to trigger the user plane network element 1320 to perform Layer 2 forwarding of Ethernet packets received through the session, and the identifier of the VN group is used to indicate that the session is a session in the VN group; send a session establishment response message to the terminal, the session establishment response message includes the Layer 2 forwarding identifier, the Layer 2 forwarding identifier is used to trigger the terminal to process the packets received through the session as Ethernet packets, or to encapsulate the data to be sent through the session into Ethernet packets before sending. User plane network element 1320 is used to receive Layer 2 forwarding identifiers and perform Layer 2 forwarding on Ethernet packets received through the session based on the Layer 2 forwarding identifiers.

[0374] Optionally, the control plane network element 1310 is used to create a group session corresponding to the VN group based on the subscription information of the VN group. This may include: sending a PFCP group session establishment request to the user plane network element 1320, wherein the group session establishment request includes some or all of the information in the subscription information of the VN group; receiving a PFCP group session establishment response, wherein the group session establishment response includes the IP information of the VTEP of the user plane network element and the VNI corresponding to the terminal, wherein the IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the VN group, and the tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

[0375] Optionally, the control plane network element 1310, used to send a Layer 2 forwarding identifier and a VN group identifier to the user plane network element, may include: sending a PFCP user session establishment request to the user plane network element 1320, wherein the PFCP user session establishment request includes a Layer 2 forwarding identifier and a VN group identifier, and the user session is associated with a group session; and receiving a PFCP user session establishment response.

[0376] Optionally, the control plane network element 1310, used to perform Layer 2 forwarding of Ethernet packets received through a session according to a Layer 2 forwarding identifier, may include: decapsulating the Ethernet packets received through the session based on the Layer 2 forwarding identifier and GTPU to obtain the initial Ethernet packet and the destination MAC address; encapsulating the initial Ethernet packet based on GTPU and forwarding it according to the destination MAC address, wherein the destination MAC address is used to indicate the Layer 2 address of the peer of the terminal; and the received Ethernet packet is information from the VN group to which the terminal belongs.

[0377] Optionally, the control plane network element 1310, used to perform Layer 2 forwarding of Ethernet packets received through a session according to a Layer 2 forwarding identifier, may include: decapsulating the Ethernet packets received through the session according to the Layer 2 forwarding identifier and a second communication protocol to obtain the initial Ethernet packet and the destination MAC address; encapsulating the initial Ethernet packet according to the second communication protocol and forwarding it according to the destination MAC address, wherein the destination MAC address is used to indicate the Layer 2 address of the peer of the terminal; and the received Ethernet packets are information from the VN group to which the terminal belongs; the second communication protocol includes: network layer network protocol, VXLAN protocol, and GTPU.

[0378] Optionally, the user plane network element 1320 is also configured to allow data transmission between the terminal and other terminals in the VN group based on the identifier of the VN group.

[0379] It should be noted that any of the method embodiments described above can be used to support or be applied to the communication system 1300.

[0380] This application also provides a readable storage medium (also called a computer-readable storage medium) that stores a program (also called code, instructions, or a computer program) that, when run on a device, causes the device to perform the steps described in the various method embodiments above.

[0381] This application also provides a program product, which includes a program that, when run on a device, causes the device to perform the steps described in the various method embodiments above.

[0382] This application also provides a chip, which includes a processor and a memory. The memory is used to store a program, and the processor is used to call and run the program stored in the memory, so that a device or equipment (such as a communication device) with the chip installed performs the steps in the above-described method embodiments.

[0383] 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 readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The program includes program code, which can be in the form of source code, object code, executable file, or some intermediate form. The readable storage medium can include at least: any entity or device capable of carrying program code to a device / app, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media. Examples include USB flash drives, portable hard drives, magnetic disks, or optical disks. In certain jurisdictions, depending on legislation and patent practice, the readable storage medium may not be an electrical carrier signal or a telecommunication signal.

[0384] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0385] In the description of this application, unless otherwise stated, " / " indicates that the objects before and after are in an "or" relationship. For example, A / B can represent A or B. "And / or" in this application merely describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. Furthermore, in the description of this application, unless otherwise stated, "multiple" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple. Additionally, to facilitate a clear description of the technical solutions of the embodiments of this application, the terms "first" and "second" are used in the embodiments of this application to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first," "second," etc., do not limit the quantity or order of execution, and that "first," "second," etc., do not necessarily imply that they are different. It should be understood that in this application, descriptions such as "in the case of," "if," "when," "if," etc., can be used interchangeably.

[0386] Furthermore, various aspects or features of this application can be implemented as methods, apparatus, or articles of manufacture using standard programming and / or engineering techniques. The term "article of manufacture" as used herein encompasses a computer program accessible from any computer-readable device, carrier, or medium. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disks, floppy disks, or magnetic tapes), optical discs (e.g., compact discs (CDs), digital versatile discs (DVDs), etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memory (EPROMs), cards, sticks, or key drives, etc.). Additionally, the various storage media described herein may represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media capable of storing, containing, and / or carrying instructions and / or data.

[0387] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0388] In the embodiments provided in this application, it should be understood that the disclosed apparatus / devices and methods can be implemented in other ways. For example, the apparatus / device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0389] 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 network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0390] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A communication method, characterized in that, Applied to control plane network elements, the method includes: Receive a session establishment request message from the terminal, wherein the session is an Internet Protocol (IP) type session; Obtain the subscription information of the virtual network (VN) group corresponding to the terminal, wherein the subscription information of the VN group includes the identifier of the VN group; Based on the subscription information of the VN group, create a group session corresponding to the VN group; Send a Layer 2 forwarding identifier and the identifier of the VN group to the user plane network element. The Layer 2 forwarding identifier is used to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets received through the session. The identifier of the VN group is used to indicate that the session is a session in the VN group. A session establishment response message is sent to the terminal. The session establishment response message includes the Layer 2 forwarding identifier. The Layer 2 forwarding identifier is used to trigger the terminal to process the packets received through the session as Ethernet packets, or to encapsulate the data to be sent through the session into Ethernet packets before sending them.

2. The method according to claim 1, characterized in that, The session establishment request message includes the terminal's feature identifier, and the step of creating a group session corresponding to the VN group based on the VN group's subscription information includes: If the feature identifier of the terminal is determined to match the feature identifier in the preset identifier set, a group session corresponding to the VN group is created according to the subscription information of the VN group, wherein the terminal corresponding to any feature identifier in the preset identifier set supports the transmission of Ethernet packets under IP type session.

3. The method according to any one of claims 1-2, characterized in that, The step of creating a group session corresponding to the VN group based on the VN group's subscription information includes: Send a Packet Forwarding Control Protocol (PFCP) group session establishment request to the user plane network element, wherein the group session establishment request includes some or all of the subscription information of the VN group; The system receives a PFCP group session establishment response, which includes the IP information of the Virtual Extended LAN Tunnel Endpoint (VTEP) of the user plane network element and the Virtual Extended LAN Identifier (VNI) corresponding to the terminal. The IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the VN group. The tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

4. The method according to any one of claims 1-3, characterized in that, The step of sending the Layer 2 forwarding identifier and the identifier of the VN group to the user plane network element includes: Sends a Packet Forwarding Control Protocol (PFCP) User Session Establishment Request to the user plane network element. The PFCP User Session Establishment Request includes the Layer 2 forwarding identifier and the identifier of the VN group. The user session is associated with the group session. Receive PFCP user session establishment response.

5. The method according to any one of claims 1-4, characterized in that, The step of obtaining the subscription information of the VN group corresponding to the terminal includes: Obtain the identifier of the shared VN group data corresponding to the terminal from the Unified Data Management (UDM) network element; Based on the identifier of the shared VN group data, the subscription information of the VN group corresponding to the terminal is obtained from the UDM network element.

6. The method according to claim 5, characterized in that, The session establishment request message includes the terminal's feature identifier, and the identifier for obtaining the shared VN group data corresponding to the terminal includes: If it is determined that the feature identifier of the terminal matches the feature identifier in the preset identifier set, the identifier of the shared VN group data corresponding to the terminal is obtained, wherein the terminal corresponding to any feature identifier in the preset identifier set supports the transmission of Ethernet packets under IP type session.

7. The method according to any one of claims 1-4, characterized in that, The step of obtaining the subscription information of the VN group corresponding to the terminal includes: Obtain the subscription information of the VN group from the Authentication, Authorization and Accounting (AAA) network element.

8. The method according to any one of claims 1-7, characterized in that, The session establishment response message also includes: the IP information of the Virtual Extended LAN Tunnel Endpoint (VTEP) of the user plane network element and the Virtual Extended LAN Identifier (VNI) corresponding to the terminal. The IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the VN group. The tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

9. The method according to any one of claims 2-8, characterized in that, The feature identifier includes at least one of the following: Data Network Name (DNN), General Public User Identifier (GPSI), and Permanent User Identifier (SUPI).

10. The method according to any one of claims 1-9, characterized in that, The control plane network element is a Packet Data Network Gateway Control Plane PGW-C network element, and the user plane network element is a Packet Data Network Gateway User Plane PGW-U network element; or, the control plane network element is a Session Management Function (SMF) network element, and the user plane network element is a User Plane Function (UPF) network element.

11. A communication method, characterized in that, Applied to a terminal, the method includes: Send a session establishment request message, wherein the session is an Internet Protocol (IP) type session; Receive the session establishment response message, which includes a Layer 2 forwarding identifier; Based on the Layer 2 forwarding identifier, the terminal processes the packets received through the session as Ethernet packets, or encapsulates the data to be sent through the session into Ethernet packets before sending them.

12. The method according to claim 11, characterized in that, The session establishment response message also includes: the IP information of the Virtual Extended LAN Tunnel Endpoint (VTEP) of the user plane network element and the Virtual Extended LAN Identifier (VNI) corresponding to the terminal. The IP information of the VTEP of the user plane network element and the VNI are used to configure the tunnel of the Virtual Network (VN) group to which the terminal belongs. The tunnel of the VN group is used for the user plane network element and the terminal to transmit Ethernet packets.

13. A communication method, characterized in that, Applied to a terminal, the method includes: Send a session establishment request message, wherein the session is an Internet Protocol (IP) type session; Receive session establishment response message; Based on a pre-configured Layer 2 forwarding identifier, the terminal encapsulates the data to be sent through the session into an Ethernet packet before sending it, or processes the packets received through the session as Ethernet packets.

14. The method according to any one of claims 11-13, characterized in that, The terminal encapsulates the data to be sent through the session into Ethernet packets before sending it, or processes packets received through the session as Ethernet packets, including: The terminal encapsulates the data to be sent through the session into Ethernet packets and sends the Ethernet packets encapsulated based on the Packet Data Convergence Protocol (PDCP); or... The packets received through the session are decapsulated based on the PDCP, and the received packets are information from the Virtual Network (VN) group to which the terminal belongs.

15. The method according to any one of claims 11-13, characterized in that, The terminal encapsulates the data to be sent through the session into Ethernet packets before sending it, or processes the packets received through the session as Ethernet packets. User plane network elements include: The terminal encapsulates the data to be sent through the session into an Ethernet packet and sends the Ethernet packet encapsulated based on the first communication protocol; or... The received messages are decapsulated based on the first communication protocol, and the received messages are information from the virtual network (VN) group to which the terminal belongs; The first communication protocol includes: L3 network protocol, Virtual Extended Local Area Network (VXLAN) protocol, and Packet Data Convergence Protocol (PDCP).

16. A communication system, characterized in that, Including control plane network elements and user plane network elements, The control plane network element is configured to receive a session establishment request message from a terminal, wherein the session is an Internet Protocol (IP) session; obtain the subscription information of the VN group corresponding to the terminal, wherein the subscription information of the VN group includes the identifier of the VN group; create a group session corresponding to the VN group based on the subscription information of the VN group; send a Layer 2 forwarding identifier and the identifier of the VN group to the user plane network element, wherein the Layer 2 forwarding identifier is used to trigger the user plane network element to perform Layer 2 forwarding of Ethernet packets received through the session, and the identifier of the VN group is used to indicate that the session is a session in the VN group; and send a session establishment response message to the terminal, wherein the session establishment response message includes the Layer 2 forwarding identifier, wherein the Layer 2 forwarding identifier is used to trigger the terminal to process the packets received through the session as Ethernet packets, or to encapsulate the data to be sent through the session into Ethernet packets before sending. The user plane network element is used to receive the Layer 2 forwarding identifier and perform Layer 2 forwarding on the Ethernet packets received through the session according to the Layer 2 forwarding identifier.

17. The communication system according to claim 16, characterized in that, The user plane network element is configured to perform Layer 2 forwarding of Ethernet packets received through the session according to the Layer 2 forwarding identifier, including: Based on the Layer 2 forwarding identifier, the Ethernet packets received through the session are decapsulated using the General Packet Radio Service Tunneling Protocol User Plane (GTPU) to obtain the initial Ethernet packet and the destination Media Access Control (MAC) address. The initial Ethernet packet is then encapsulated using GTPU and forwarded according to the destination MAC address. The destination MAC address is used to indicate the Layer 2 address of the peer of the terminal. The received Ethernet packets are information from the VN group to which the terminal belongs.

18. The communication system according to claim 16, characterized in that, The user plane network element is used to perform Layer 2 forwarding of Ethernet packets received through the session according to the Layer 2 forwarding identifier, including: According to the Layer 2 forwarding identifier, the Ethernet packets received through the session are decapsulated based on the second communication protocol to obtain the initial Ethernet packet and the destination MAC address. The initial Ethernet packet is then encapsulated based on the second communication protocol and forwarded according to the destination MAC address. The destination MAC address is used to indicate the Layer 2 address of the peer of the terminal. The received Ethernet packet is information from the VN group to which the terminal belongs. The second communication protocol includes: L3 network protocol, Virtual Extended Local Area Network (VXLAN) protocol, and General Packet Radio Service Tunneling Protocol User Plane (GTPU).

19. The communication system according to any one of claims 16-18, characterized in that, The user plane network element is also used to allow data transmission between the terminal and other terminals in the VN group based on the identifier of the VN group.

20. A communication device, characterized in that, include: A module or unit for performing the communication method as described in any one of claims 1 to 10, or a module or unit for performing the communication method as described in any one of claims 11 to 15.

21. A readable storage medium, characterized in that, The readable storage medium stores a program that, when run on the device, causes the device to perform the communication method as described in any one of claims 1 to 15.

22. A program product, characterized in that, Includes: a program that, when run on a device, causes the device to perform the communication method as described in any one of claims 1 to 15.

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