Communication method and apparatus

Abstract

The present application provides a communication method and apparatus. In the method, sessions established by a user plane network element for a plurality of terminal devices in a group are associated with an address range, and the user plane network element transmits first service data by means of at least two sessions among the plurality of sessions associated with the address range. Therefore, when an x device switches a connection between any two terminal devices in the group, such as switching from connecting to a terminal device 1 to connecting to a terminal device 2, the at least two sessions may comprise sessions established by the user plane network element for the terminal device 1 and the terminal device 2. In this way, regardless of whether the x device is within the signal coverage of the terminal device 1 or within the signal coverage of the terminal device 2, the x device can still receive a downlink service data packet by means of the at least two sessions, thereby improving the service reliability of the x device.

Description

A communication method and apparatus

[0001] This application claims priority to Chinese Patent Application No. 202410918794.3, filed on July 9, 2024, entitled "A Communication Method and Apparatus", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to a communication method and apparatus. Background Technology

[0003] The second device can access the network through the first device. The second device does not have the ability to directly access the network; for example, the second device is device x, such as an Internet of Things (IoT) device. The first device has the ability to access the network; for example, the first device can be user equipment (UE), customer premises equipment (CPE), etc. For instance, the second device can establish a connection with the terminal device through non-3GPP access technology, thereby accessing the network and transmitting service data through the terminal device.

[0004] However, when the second device transmits service data to the network side through the first device, the second device may move out of the signal coverage area of ​​the terminal device. For example, if the second device transmits uplink service data to the network side through the first device 1, and the network side responds by transmitting downlink service data to the first device 1, and the second device moves out of the signal coverage area of ​​the currently connected first device 1, the connection between the second device and the first device 1 will be interrupted, and the second device will be unable to receive the downlink service data. Therefore, the service reliability of the second device may be low. Summary of the Invention

[0005] This application provides a communication method and apparatus to improve the service reliability of a second device.

[0006] A first aspect provides a communication method, comprising: a user plane network element receiving first service data from a data network. If the destination address of the first service data belongs to an address range associated with multiple sessions, the user plane network element transmits the first service data to at least two terminal devices through at least two of the multiple sessions, wherein the at least two terminal devices are in a group, the group includes multiple terminal devices capable of accessing a first network, the multiple sessions are sessions established by the user plane network element for a second device, the second device accesses the first network through the terminal devices, and the address range is the address range used by the service data of the multiple terminal devices in the group.

[0007] Based on the method described in the first aspect, multiple sessions are associated with address ranges. The user plane network element transmits first service data through at least two of these multiple sessions associated with the address range. This means that before the user plane network element receives the first service data, it establishes multiple corresponding sessions for each terminal in the group. That is, one terminal in the group corresponds to one session, which is used to transmit service data for the second device. It should be noted that the aforementioned multiple sessions are Protocol Data Unit (PDU) sessions initiated by the terminal device in the 5G core network (5GC). These sessions are used to transmit service data for the second device and may be shared by multiple second devices. Therefore, they can be understood as sessions established by the user plane network element for the second device. Since one terminal device in the group corresponds to one session, when the second device switches connections between any two terminal devices in the group, such as switching from a connection with terminal device 1 to a connection with terminal device 2, at least two sessions may include those established by the user plane network element for both terminal device 1 and terminal device 2. Therefore, regardless of whether the second device is within the signal coverage area of ​​terminal device 1 or terminal device 2, it can still receive downlink service data packets through at least two sessions, thereby improving the service reliability of the second device. Furthermore, since the second device can promptly receive downlink service data packets when disconnecting from terminal device 1 and moving to the signal coverage area of ​​terminal device 2, the service reliability of the second device is guaranteed. Here, the second device can be an "x device," which is a device that does not support network access via 3rd Generation Partnership Project (3GPP) access technology. The x device can be an IoT device (such as a laptop), and the terminal device can be a mobile phone. The difference between a terminal device and an x ​​device is that a terminal device supports cellular access technology, NAS messaging modules, and SIM cards, thus possessing the ability to access the network. An x device does not support cellular access technology, does not support SIM cards, and supports non-3GPP access technologies, therefore it does not have the ability to directly access the network. However, the x device can establish a connection with the terminal device through non-3GPP access technology and access the network through the terminal device. Non-3GPP access technologies include wireless local area network (WLAN) access, Bluetooth access, wired access, fixed network access, and short-range access technologies. It's important to note that service data packets are the actual data transmitted during communication, while service data is the information carried by these data packets. In other words, service data packets are the carriers of data, while service data is the specific content contained within those data packets.

[0008] Optionally, at least two sessions constitute multiple sessions. That is, for service data packets whose addresses belong to the address range of the group, they are transmitted across multiple sessions. Since multiple sessions are sessions established by multiple terminal devices within the group, when device x switches connections between any two terminal devices within the group, such as switching from terminal device 1 to terminal device 2, it can be understood that device x moves out of the signal coverage area of ​​the currently connected terminal device 1, thus disconnecting from terminal device 1 and moving to the signal coverage area of ​​terminal device 2 to establish a connection with terminal device 2. Therefore, device x can still receive downlink service data packets through the session with terminal device 2, thereby improving the service reliability of device x. Furthermore, since device x can receive downlink service data packets promptly when disconnecting from terminal device 1 and moving to the signal coverage area of ​​terminal device 2, the service reliability of device x is guaranteed.

[0009] The address range and the association between multiple sessions can be determined by the user plane network element itself, or it can be indicated by other network elements.

[0010] Optionally, before the user plane network element receives the first service data from the data network, the communication method further includes: the user plane network element receiving a first message from a session management network element, the first message including indication information for mapping address ranges to multiple sessions. The user plane network element, based on the indication information, saves the mapping relationship between address ranges and multiple sessions, the mapping relationship being used to determine the multiple sessions.

[0011] The first message can be an N4 message. This instruction tells the user plane network element to associate an address range with multiple sessions. Therefore, the user plane network element can store the mapping between the address range and multiple sessions based on the instruction, so that it can subsequently identify the multiple sessions through this mapping.

[0012] Optionally, the indication information may include information on multiple sessions and / or address ranges, instructing the user plane network element to map the address ranges to multiple sessions.

[0013] The information for multiple sessions can be group identification information, which can be information that can uniquely identify the group, such as group identity (group ID), or at least one of data network name (DNN) and slice information. The slice information can be, for example, Network Slice Selection Assistance Information (NSSAI).

[0014] Group identification information can be used to associate multiple sessions. Subsequent user plane network elements can determine the multiple sessions corresponding to a group's identification information by identifying that the destination address of the first service data belongs to an address range associated with that address range. Group identification information can also be used to select the same network element for terminal devices within the same group when establishing a session. For example, when terminal devices 1 and 2 establish a PDU session within the same group, the AMF network element selects the same SMF network element for both terminal devices 1 and 2 based on the group's identification information. Similarly, the SMF network element selects the same UPF network element for both terminal devices 1 and 2 based on the group's identification information.

[0015] Optionally, if the destination address of the first service data belongs to the address range associated with multiple sessions, the user plane network element transmits the first service data to at least two terminal devices through at least two of the multiple sessions. This may include: if the destination address of the first service data belongs to the address range, the user plane network element determines the multiple sessions corresponding to the address range according to the correspondence, and transmits the first service data to at least two terminal devices through at least two of the multiple sessions.

[0016] It is understandable that after the user plane network element stores the correspondence between the address range and multiple sessions, when the user plane network element receives the first service data, it can determine multiple sessions through the correspondence between the address range and multiple sessions, and then send the first service data to at least two terminal devices through at least two sessions corresponding to the address range of the group. The at least two terminal devices may include terminal devices connected to device x, which can reduce the probability of device x losing the first service data and improve the reliability of transmitting the first service data.

[0017] Optionally, the user plane network element transmits the first service data to at least two terminal devices through at least two of the multiple sessions, which may include: the user plane network element copying the first service data into multiple copies, and transmitting one copy of the first service data to the terminal device through each of the multiple sessions.

[0018] In other words, the user plane network element copies the first service data to multiple sessions, and each session transmits a copy of the first service data, further improving the reliability of the user plane network element in transmitting the first service data.

[0019] Secondly, a communication method is provided. This method can be executed by a first device, by a module applied to the first device (e.g., a processor, chip, or chip system), or by a logical node, logical module, or software capable of implementing all or part of the functions of the first device. For ease of description, the following description assumes the method is executed by the first device. The method includes: the first device receiving second service data from a second device. If the address range of a group contains the address of the second service data, the first device sends the second service data to a user plane network element through the session corresponding to the group. The group includes multiple devices capable of accessing a first network, the multiple devices including the first device, and the second device accesses the first network through the devices in the group.

[0020] Based on the second aspect of the method, since the second device accesses the first network through a terminal device in the group, it can also access the first network through the first device. If the address of the second service data falls within the address range of the group, the second service data is sent to the user plane network element through the session corresponding to the group. Thus, by associating the address of the second service data with the address range of the group, and thereby matching the session corresponding to the address range of the group, the first device can match the session related to the second service data, or in other words, match the session related to the service involved in the second service data, thereby improving the reliability of transmitting the second service data.

[0021] The second device can be the aforementioned device x.

[0022] In one possible implementation, the address is the source address; the communication method may further include: a first device receiving first service data from a user plane network element, determining the second device corresponding to the destination address of the first service data based on the correspondence between the source address of the second service data and the second device, and sending the second service data to the second device. Wherein, the source address of the second service data is the same as the destination address of the first service data.

[0023] Optionally, before the first device receives the first service data from the user plane network element, the communication method may further include: the first device storing the correspondence between the source address of the second service data and the second device.

[0024] It is understood that the first device pre-stores the correspondence between the source address of the second service data and the second device. Since the source address of the second service data is the same as the destination address of the first service data, the first device determines that the destination address of the first service data corresponds to the second device, and then sends the second service data to the second device. In this way, when the second device is connected to the data network through the first device, the first service data can be sent to the second device through the first device, ensuring the reliability of the second device's services.

[0025] Optionally, before the first device receives the second service data from the second device, the communication method may further include: the first device receiving a second message from a session management network element, the second message indicating that the session has been successfully established, the second message including the address range of the group corresponding to the session, the first device storing the correspondence between the address range of the session and the group according to the second message, the correspondence between the address range of the session and the group being used to determine the session corresponding to the group.

[0026] The second message can be carried in a downlink NAS transport (DL NAS transport) message and includes the address range of the group corresponding to the session. The second message implicitly instructs the first device to map the session to the group's address range, thus allowing the first device to store this mapping. Subsequently, when the first device receives second service data from the second device, it can determine the session corresponding to the group through the mapping, and then send the second service data to the user plane network element, ensuring the reliability and continuity of the second device's services.

[0027] In one possible implementation, the communication method may further include: upon establishing a connection between the first device and the second device, obtaining an address assigned to the second device by the session management network element from the session management network element. The first device then sends the address assigned to the second device to the second device. The address assigned to the second device by the session management network element includes the address of the second service data.

[0028] The address range of the group includes the address allocated to the second device. In other words, the session management network element allocates an address to the second device from the address range of the group. The address allocated to the second device by the session management network element includes the address of the second service data. That is, the second device subsequently uses the address allocated to it as the source address to encapsulate the second service data and transmit it.

[0029] In this way, the second device always uses the address assigned to it by the session management network element to transmit service data, so that when the data network receives service data, it always recognizes that it is the same device accessing the network, thus ensuring the service continuity between the second device and the data network.

[0030] Thirdly, a communication method is provided, comprising: a user plane network element determining that the address of a first user equipment (User Equipment) is updated from being associated with a first session to being associated with a second session. When the User plane network element receives first data from a data network service, the User plane network element associates the address of the first User Equipment with the second session and transmits the first data to a third User Equipment through the second session. Wherein, the first session is a session of the second User Equipment, the second session is a session of the third User Equipment, the second User Equipment and the third User Equipment are contained in the same group, the User Equipment in the group has the ability to access a first network, the first User Equipment accesses the first network through the User Equipment in the group, and the destination address of the first data is the same as the address of the first User Equipment.

[0031] Based on the third aspect of the method, the user plane network element determines that the address of the first user equipment (User Equipment) is updated from being associated with the first session to being associated with the second session. This means the first User Equipment switches its connection from the second User Equipment to the third User Equipment. Therefore, when the user plane network element receives the first data from the data network, since the service is associated with the address of the first User Equipment (i.e., the destination address of the first data is the address of the first User Equipment), the user plane network element associates the first data with the second session based on the address of the first User Equipment and transmits the first data through the second session. This allows the first User Equipment to move between different terminal devices in the group while maintaining its own address, enabling service data to be transmitted to the terminal device connected to the first User Equipment (i.e., the third User Equipment), and then to the first User Equipment, thus supporting communication between the first User Equipment and the data network and ensuring the service reliability of the first User Equipment.

[0032] In one possible implementation, the user plane network element receives first information sent from a second user equipment and / or a third user equipment, the first information indicating second session information and the address of the first user equipment; the user plane network element determining that the address of the first user equipment is updated from being associated with the first session to being associated with the second session may include: the user plane network element determining, based on the first information, that the address of the first user equipment is updated from being associated with the first session to being associated with the second session.

[0033] It is understandable that the first message can reuse existing signaling for transmission. For example, the first message can be carried in a performance measurement functionality (PMF) request message.

[0034] The first message can also be sent via newly added signaling, decoupled from existing signaling, and is not limited here. The first message indicates the second session information and the address of the first user equipment, that is, it implicitly indicates the association between the address of the second session and the address of the first user equipment.

[0035] Thus, by using the first information from the second user equipment and / or the third user equipment, the user plane network element can more flexibly determine the address of the first user equipment and associate it with the second session. Furthermore, by using the first information, the user plane network element can ensure that the first data is transmitted to the terminal device (i.e., the third user equipment) connected to the first user equipment, thereby guaranteeing the service reliability of the first user equipment.

[0036] Optionally, the association between the service and the address of the first user equipment includes: the destination address of the first data is the same as the address of the first user equipment.

[0037] In another possible implementation, the communication method may further include: the user plane network element receiving second data from a third user equipment and obtaining the source address of the second data. The user plane network element determining that the address of the first user equipment has been updated from association with a first session to association with a second session may further include: the user plane network element determining that the address of the first user equipment has been updated from association with a first session to association with a second session based on the fact that the source address of the second data is the same as the address of the first user equipment.

[0038] It is understandable that the second data can be the uplink data of the service. The source address of the second data is the same as the address of the first user equipment. In other words, the second data is data from the first user equipment. The user plane network element receives the second data from the third user equipment. Therefore, the user plane network element determines that the first user equipment is connected to the third user equipment, that is, the session associated with the address of the first user equipment is changed to the session of the third user equipment (the second session).

[0039] In this way, the user plane network element can ensure that the first data is transmitted to the terminal device connected to the first user equipment, thereby guaranteeing the service reliability of the first user equipment.

[0040] Optionally, the user plane network element determines multiple sessions associated with the address range of the group, including the address of the first data, based on the address range of the group, and transmits the first data through at least two of the multiple sessions.

[0041] This avoids data packet loss caused by frequent switching between terminal devices within a group when the first user device moves. For example, if the group includes terminal devices A, B, and C, device x might switch from connecting to terminal device A to terminal device B, and then switch back to terminal device C within a short period (e.g., 2 seconds). When the UPF network element determines that the session corresponding to device x's IP address has been updated (switching from connecting to terminal device A to terminal device B), it detects that device x is moving and transmits data packets across multiple PDU sessions associated with the group, thus preventing data packet loss.

[0042] In another possible implementation, the second user equipment is the master equipment; the communication method may further include: the user plane network element can transmit first data to the second user equipment through a first session, based on the second user equipment being the master equipment.

[0043] A master device can be a group-level device used to manage slave devices within its group, such as establishing connections with slave devices and exchanging signaling information with them. The master device can determine the connection status of each slave device within the group to the first user device in real time; for example, when a slave device connects to the first user device, it reports the address of the first user device to the master device in real time. The master device may also have at least one of the following capabilities: assigning addresses, management addresses, or mappings between management addresses and slave devices to the first user device (such as device x mentioned above).

[0044] Fourthly, a communication method is provided. This method can be executed by a second user equipment, by a module applied to the second user equipment (such as a processor, chip, or chip system), or by a logical node, logical module, or software capable of implementing all or part of the functions of the second user equipment. For ease of description, the following description will take the execution of this method by a second user equipment as an example.

[0045] The method includes: a second user equipment receiving second information from a third user equipment; and, if the second user equipment receives first data from a user plane network element, the second user equipment sending the first data to the third user equipment based on the fact that the address of the first data is the same as the address of the first user equipment. The second information indicates the address of the first user equipment communicatively connected to the third user equipment; the second and third user equipments are contained in the same group; the second user equipment is the master device; the third user equipment is the slave device; user equipment in the group has the ability to access a first network; and the first user equipment accesses the first network through user equipment in the group.

[0046] Based on the method in the fourth aspect, when the third user equipment (slave device) connects to the first user equipment, it sends the address of the connected first user equipment to the second user equipment (master device). This allows the second user equipment to obtain the connection status between the third user equipment and the first user equipment within the group. Since the address of the first data is the same as the address of the first user equipment, the second user equipment can determine that the first data should be sent to the first user equipment. The second user equipment, having obtained from the second information that the device communicating with the first user equipment is the third user equipment, sends the first data to the third user equipment, which then forwards the first data to the first user equipment. This ensures that when the first user equipment moves between different terminal devices within the group, service data can be transmitted to the first user equipment while maintaining its address, supporting communication between the first user equipment and the data network and guaranteeing the service reliability of the first user equipment.

[0047] Optionally, before the second user equipment receives the second information from the third user equipment, the method further includes: the second user equipment receiving a request message, the request message being used to request an address to be allocated to the first user equipment; the second user equipment sending a message to the first user equipment according to the request message to allocate an address to the first user equipment from the address range of the group, the address allocated to the first user equipment including the address of the first user equipment.

[0048] It is understandable that, as the second user equipment (UE) is the primary device, it has the capability to allocate addresses to the first UE. Therefore, after receiving a request message requesting an address to be allocated to the first UE, the second UE allocates an address to the first UE from the address range of the group. The address allocated to the first UE can be any address within the address range of the group. Subsequently, the first UE uses the address allocated to it to send service data, ensuring that the data network always recognizes the first UE as the access point, thus preventing the data network from interrupting the first UE's services.

[0049] Optionally, the request message originates from either the first user equipment (User Equipment) or the third user equipment (User Equipment). The second user equipment directly receives the request message from the first user equipment, requesting an address to be allocated to the first user equipment. Alternatively, the first user equipment sends a request message to the third user equipment. Upon receiving the request message, the third user equipment, being a slave device, does not have the capability to allocate an address to the first user equipment. Therefore, it treats the second user equipment as the master device and forwards the request message to the second user equipment. This ensures that only the second user equipment, acting as the master device, allocates an address to the first user equipment, preventing multiple terminal devices from allocating different addresses to the first user equipment. This also prevents the first user equipment from using different addresses to send service data, thus avoiding disruption to the first user equipment's service continuity.

[0050] Optionally, the communication method may further include: the second user equipment sending first information to the user plane network element, the first information indicating the session information of the third user equipment and the address of the first user equipment, wherein the first information is used to determine that the first address is updated from being associated with a first session to being associated with a second session, the first session being the session of the second user equipment, and the second session being the session of the third user equipment.

[0051] It is understandable that the technical effects of the method in the fourth aspect mentioned above can also be referred to the relevant introduction in the third aspect mentioned above, and will not be repeated here.

[0052] Fifthly, a communication method is provided. This method can be executed by a third user equipment, by a module applied to the third user equipment (such as a processor, chip, or chip system), or by a logical node, logical module, or software capable of implementing all or part of the functions of the third user equipment. For ease of description, the following description will take the execution of this method by a third user equipment as an example.

[0053] The method includes: a third user equipment sending second information to a second user equipment, the second information indicating the address of a first user equipment that has established a connection with the third user equipment; the second user equipment and the third user equipment being contained in the same group; the second user equipment being the master equipment; user equipment in the group having the ability to access a first network; and the first user equipment accessing the first network through user equipment in the group. The third user equipment receives first data from the second user equipment and / or user plane network elements, the destination address of the first data being the same as the address of the first user equipment.

[0054] It is understandable that the third user equipment can directly receive the first data from the user plane network element, or the user plane network element can send the first data to the second user equipment as the master equipment based on the second user equipment, and the second user equipment can send the first data to the third user equipment based on the second information, so that the third user equipment can receive the first data from the second user equipment.

[0055] Optionally, the communication method may further include: a third user equipment sending first data to a first user equipment.

[0056] Optionally, the third user equipment sending the first data to the first user equipment may include: when the third user equipment receives the first data sent by the user plane network element and the first data sent by the second user equipment, performing deduplication processing on the first data. The third user equipment then sends the first data to the first user equipment.

[0057] In other words, the third user equipment receives the same first data from the user plane network element and the second user equipment, such as two identical data packets. Deduplication processing is performed on the first data, such as discarding the duplicate data packet. Alternatively, deduplication can be omitted, and the third user equipment can send all received first data to the first user equipment, which can reduce the first data loss rate.

[0058] Optionally, before the third user equipment sends the second information to the second user equipment, the communication method may further include: the third user equipment receiving a request message from the first user equipment, the request message being used to request the allocation of an address for the first user equipment; and the third user equipment sending the request message to the second user equipment, the second user equipment being the master equipment.

[0059] Since the master device has the ability to allocate an address to the first user equipment, while the slave device does not, the third user equipment sends a request message to the second user equipment, which then allocates an address to the first user equipment.

[0060] It is understandable that the technical effects of the method in the fifth aspect mentioned above can also be referred to the relevant introduction in the fourth aspect mentioned above, and will not be repeated here.

[0061] A sixth aspect provides a communication device. The communication device includes a processor configured to perform the method of any embodiment of the first or second aspect, or to perform the method of any embodiment of the third to fifth aspects.

[0062] In one possible implementation, the communication device described in the sixth aspect may further include a transceiver. The transceiver may be a transceiver circuit or an interface circuit. The transceiver can be used for communication between the communication device described in the sixth aspect and other communication devices.

[0063] In one possible implementation, the communication device described in the sixth aspect may further include a memory. This memory may be integrated with the processor or disposed separately. The memory may be used to store computer programs and / or data involved in the methods of any embodiment of the first or second aspect, or computer programs and / or data involved in the methods of any embodiment of the third to fifth aspects.

[0064] Furthermore, the technical effects of the communication device described in the sixth aspect can be referenced to the technical effects of any embodiment in the first or second aspect, or the technical effects of any embodiment in the third to fifth aspects, which will not be repeated here.

[0065] A seventh aspect provides a communication device. The communication device includes a processor coupled to a memory, the processor being configured to execute a computer program or instructions stored in the memory to cause the communication device to perform the method of any embodiment of the first or second aspect, or to cause the communication device to perform the method of any embodiment of the third to fifth aspects.

[0066] In one possible implementation, the communication device may further include a transceiver. The transceiver may be a transceiver circuit or an interface circuit. The transceiver can be used for communication between the communication device and other communication devices.

[0067] In one possible implementation, the communication device further includes the memory for storing the aforementioned computer program or instructions. Optionally, the memory and processor are integrated together.

[0068] Furthermore, the technical effects of the communication device described in the seventh aspect can be referred to the technical effects of any embodiment in the first or second aspect, or the technical effects of any embodiment in the third to fifth aspects, which will not be repeated here.

[0069] Eighthly, a communication device is provided. This communication device is used to implement the method of any of the embodiments of the second, fourth, or fifth aspects. The communication device may be a terminal device.

[0070] A ninth aspect provides a communication system. The communication system includes: a user plane network element for performing the method described in any embodiment of the first or third aspect, and a first device for performing the second aspect; or, a user plane network element for performing the method described in any embodiment of the first or third aspect, and a second user device for performing the fourth aspect; or, a user plane network element for performing the method described in any embodiment of the first or third aspect, and a third user device for performing the fifth aspect.

[0071] A tenth aspect provides a communication method, the method comprising: a user plane network element performing the method described in any embodiment of the first or third aspect, and a first device performing the method described in the second aspect; or, a user plane network element performing the method described in any embodiment of the first or third aspect, and a second user device performing the method described in the fourth aspect; or, a user plane network element performing the method described in any embodiment of the first or third aspect, and a third user device performing the method described in the fifth aspect.

[0072] Eleventhly, a computer-readable storage medium is provided, comprising: a computer program or instructions; when the computer program or instructions are executed, causing the method of any embodiment of the first or second aspect described above to be implemented, or causing the method of any embodiment of the third to fifth aspects described above to be implemented.

[0073] In a twelfth aspect, a computer program product is provided, comprising a computer program or instructions that, when executed, cause the method of any embodiment of the first or second aspect described above to be implemented, or cause the method of any embodiment of the third to fifth aspects described above to be implemented. Attached Figure Description

[0074] Figure 1 is a schematic diagram of the 5GS architecture;

[0075] Figure 2 is a schematic diagram of the 5GS architecture.

[0076] Figure 3 is a schematic diagram of a family group;

[0077] Figure 4 is a schematic diagram of the communication system provided in an embodiment of this application;

[0078] Figure 5 is a schematic diagram of the network architecture provided in an embodiment of this application;

[0079] Figure 6 is a schematic diagram of the communication method provided in an embodiment of this application;

[0080] Figure 7 is a schematic diagram of the communication method provided in an embodiment of this application (II).

[0081] Figure 8 is a schematic diagram of the communication method provided in the embodiment of this application.

[0082] Figure 9 is a schematic diagram of the communication method provided in the embodiments of this application;

[0083] Figure 10 is a schematic diagram of the communication device provided in an embodiment of this application;

[0084] Figure 11 is a schematic diagram of the structure of the communication device provided in the embodiment of this application. Detailed Implementation

[0085] The technical solutions of this application embodiment can be applied to various communication systems, such as Wireless Fidelity (Wi-Fi) systems, vehicle-to-everything (V2X) communication systems, device-to-device (D2D) communication systems, vehicle-to-everything (V2X) communication systems, fourth-generation (4G) mobile communication systems, such as long-term evolution (LTE) systems, worldwide interoperability for microwave access (WiMAX) communication systems, fifth-generation (5G) mobile communication systems, such as new radio (NR) systems, and future communication systems.

[0086] For ease of understanding, the technical terms involved in the embodiments of this application will be introduced below.

[0087] 1. 5G mobile communication system (abbreviated as 5G system (5GS)):

[0088] Figure 1 is a schematic diagram of the 5GS architecture. As shown in Figure 1, 5GS includes: access network (AN) and CN, and may also include: terminals.

[0089] There may be one or more terminals. A terminal may be a terminal with transceiver functions, or it may be a chip or chip system installed in the terminal. The terminal may also be referred to as UE, access terminal, subscriber unit, user station, mobile station (MS), mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication equipment, user agent, or user equipment. The terminals in the embodiments of this application may be mobile phones, cellular phones, smartphones, tablets, wireless data cards, personal digital assistants (PDAs), wireless modems, handsets, laptop computers, machine-type communication (MTC) terminals, computers with wireless transceiver capabilities, virtual reality (VR) terminals, augmented reality (AR) terminals, smart home devices (e.g., refrigerators, televisions, air conditioners, electricity meters, etc.), intelligent robots, robotic arms, workshop equipment, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical care, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, vehicle-mounted terminals, and roadside units with terminal functions. The terminal in this application can also be an onboard module, onboard unit, onboard component, onboard chip, or onboard unit that is built into a vehicle as one or more components or units. The terminal device can also be other devices with terminal functions; for example, it can be a device that functions as a terminal in D2D communication.

[0090] The embodiments of this application do not limit the device form of the terminal. The device used to implement the functions of the terminal device can be the terminal device itself; it can also be a device that supports the terminal device in implementing the functions, such as a chip system. The device can be installed in the terminal device or used in conjunction with the terminal device. In the embodiments of this application, the chip system can be composed of chips or can include chips and other discrete components.

[0091] The aforementioned AN (Access Network Adapter) is used to implement access-related functions. It can provide network access functionality for authorized users in a specific area and determine transmission links of different quality based on user level and service requirements to transmit user data. The AN forwards control signals and user data between the terminal and the CN (Radio Access Network). The AN may include access network equipment, also known as radio access network (RAN) equipment. The CN is primarily responsible for maintaining the mobile network's subscription data and providing terminals with functions such as session management, mobility management, policy management, and security authentication. The CN mainly includes the following network elements: User Plane Function (UPF) network element, Authentication Server Function (AUSF) network element, Access and Mobility Management Function (AMF) network element, Session Management Function (SMF) network element, Network Slice Selection Function (NSSF) network element, Network Exposure Function (NEF) network element, Network Function Repository Function (NRF) network element, Policy Control Function (PCF) network element, Unified Data Management (UDM) network element, Unified Data Repository (UDR) network element, and Application Function (AF).

[0092] RAN equipment, also known as access network device, can be one or more. An access network device can be a device with wireless transceiver capabilities, or it can be a chip or chip system located within the device, situated in the access network (AN) of the communication system, to provide access services to terminals. For example, an access network device can be called a radio access network (RAN) device, and it can be part of a future mobile communication system. In future mobile communication systems, access network devices may also have other naming conventions, all of which are covered within the protection scope of the embodiments of this application, and this application does not impose any limitations on them. Alternatively, the access network device may also include 5G, such as a gNB in ​​a new radio (NR) system, or one or a group of antenna panels (including multiple antenna panels) of a 5G base station, or it may be a network node constituting a gNB, a transmission and reception point (TRP) or transmission point (TP), or a transmission measurement function (TMF), such as a central unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU), an RSU with base station functionality, or a wired access gateway, or a 5G core network element, etc. Alternatively, the access network device may also include: an access point (AP) in a wireless fidelity (WiFi) system, a wireless relay node, a wireless backhaul node, various forms of macro base stations, micro base stations (also known as small cells), relay stations, access points, wearable devices, vehicle-mounted equipment, etc.

[0093] In this network, CU and DU can be configured separately or included in the same network element, such as a baseband unit (BBU). RU can be included in radio frequency equipment or radio frequency units, such as remote radio units (RRUs), active antenna units (AAUs), or remote radio heads (RRHs). It is understood that network equipment can be CU nodes, DU nodes, or a combination of CU and DU nodes. Furthermore, CUs can be classified as network equipment in the access network (RAN) or in the core network (CN); there are no restrictions on this classification.

[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 ORAN system, CU can also be called O-CU (open CU), DU can also be called 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. For ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples. 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 and hardware modules.

[0095] UPF network elements are primarily responsible for user data processing (forwarding, receiving, billing, etc.). For example, a UPF network element can receive user data from a data network (DN) and forward that data to the terminal through access network equipment. A UPF network element can also receive user data from the terminal through access network equipment and forward that data to the DN. A DN network element refers to the operator's network that provides data transmission services to users. Examples include Internet Protocol (IP), IP Multimedia Service (IMS), and the Internet. A DN can be an external network of the operator or a network controlled by the operator, used to provide services to terminal devices.

[0096] The AUSF network element is mainly used to perform security authentication for terminals.

[0097] AMF network elements are primarily used for mobility management in mobile networks. Examples include user location updates, user network registration, and user handover.

[0098] SMF network elements are primarily used for session management in mobile networks. This includes functions such as session establishment, modification, and release. Other functions include assigning IP addresses to users and selecting UPF network elements that provide packet forwarding capabilities.

[0099] The PCF network element primarily supports providing a unified policy framework to control network behavior, providing policy rules to the control layer network functions, and is also responsible for acquiring user subscription information related to policy decisions. The PCF network element can provide policies to the AMF and SMF network elements, such as Quality of Service (QoS) policies and slice selection policies.

[0100] NSSF network elements are mainly used to select network slices for terminals.

[0101] NEF network elements are primarily used to support the opening of capabilities and events.

[0102] UDM network elements are mainly used to store user data, such as subscription data and authentication / authorization data.

[0103] UDR network elements are mainly used to store structured data, including contract data, policy data, externally exposed structured data, and application-related data.

[0104] The AF primarily supports interaction with the CN to provide services, such as influencing data routing decisions, policy control functions, or providing third-party services to the network side. Optionally, the AF can provide personal identification number (PIN) services, also known as PIN-AF.

[0105] When the 5GC (5G core network) supports untrusted non-3GPP (N3G) access, the architecture of 5GS is shown in Figure 2. The non-3GPP interworking function (N3IWF) is also called the untrusted non-3GPP access gateway, such as an untrusted WLAN access gateway, to support untrusted WLAN access technology.

[0106] Furthermore, 5GC can also support trusted non-3GPP access and / or wired network access. Trusted non-3GPP networks include trusted WLAN networks, and wired networks include fixed home network access. The network-side architecture is similar to that of untrusted non-3GPP access; for example, N3IWF can be replaced by a trusted non-3GPP gateway function (TNGF) or a wired network access gateway function (W-AGF). Access network equipment between the UE and the aforementioned access gateways (such as TNGF or W-AGF) includes WLAN APs, fixed access network (FAN) equipment, switches, routers, etc.

[0107] N3G access technologies include WLAN access technologies and wired access technologies. WLAN access technologies correspond to WLAN APs deployed in campuses or WLAN AP hotspots deployed in public places, while wired access technologies correspond to wired access deployed in home networks. Furthermore, WLAN access technologies can be divided into trusted WLAN and untrusted WLAN. In summary, non-3GPP access technologies include trusted non-3GPP access, untrusted non-3GPP access, trusted WLAN access, untrusted WLAN access, and wired access, also known as fixed-line access. Regardless of whether it is trusted non-3GPP access or untrusted non-3GPP access, the core network side can support the point-to-point interface protocol shown in Figure 2, or support the service-oriented interface consistently used in the 3GPP access core network architecture shown in Figure 1.

[0108] It should be noted that this application uses a 5G system as an example to introduce the relevant technical solutions, but the application of these technical solutions is not limited to 5G systems. It is understood that these technical solutions may also be applicable to future communication systems.

[0109] 2. Group

[0110] In one possible scenario, for example, Figure 3 is a schematic diagram of a family group.

[0111] To enable 5GC to support home services, operators will deploy home gateways in users' homes, such as customer premises equipment (CPE) as shown in Figure 3.

[0112] As shown in Figure 3(1), a family can deploy multiple 5G CPEs, and each of the multiple 5G CPEs is independent, that is, they can be managed independently. Each 5G CPE accesses the Internet through the family (to home, to H) interconnection private network.

[0113] As shown in Figure 3(2), a household can deploy multiple 5G CPEs, and these 5G CPEs can be cascaded. For example, any one of the multiple 5G CPEs can be configured as the main CPE, which accesses the basic access distribution plane through the toH interconnection private network. Among them, the eUPF in the toH interconnection private network is mainly responsible for home access, that is, the home gateway accesses the 5GC network by connecting to the eUPF. The eUPF is responsible for handling various services related to the home network, such as IPTV (Internet Protocol TV) services, Internet services, and services for mobile phones to remotely access home devices (such as mobile phones accessing home cameras outdoors through the macro network). The UPF in the basic access distribution plane is mainly responsible for large network services, that is, mobile phones access the 5GC through the base station of the macro network and perform various services, such as Internet access and IMS voice services.

[0114] 5G CPE has cellular access capabilities, supports NAS messaging modules, and supports SIM cards. Therefore, when a 5G CPE accesses a 5GC through a cellular base station, its behavior is the same as that of a conventional terminal device. Thus, a 5G CPE can also be defined as a UE. It is understood that the terminal device involved in the embodiments of this application can be a 5G CPE. For ease of explanation, this application will use a UE as an example to describe the relevant solutions.

[0115] Users may need to deploy multiple 5G CPEs in their homes, which means deploying multiple UEs. Since these UEs belong to the same home network, operators want to manage these UEs as a group in a unified manner, such as unified billing management and unified quality of service (QoS) control.

[0116] It should be understood that the term "family group" here does not necessarily refer to members of the group having a family relationship in the conventional sense. A home gateway can be deployed in homes, hotels, cafes, etc. In such scenarios, terminals belonging to the same home network (such as the aforementioned 5G CPE) can be considered to have the same family group attribute.

[0117] 3. X equipment

[0118] The x device can be a terminal device that supports network access via non-3GPP access technologies, or in other words, an x ​​device can be a terminal device that only supports network access via non-3GPP access technologies (i.e., a non-3GPP device), meaning it does not support network access via 3GPP access technologies and is generally not considered a UE in the conventional sense. For example, an x ​​device does not support non-access stratum (NAS) modules and / or does not support SIM cards, thus it is a device that does not have the capability to directly access 5GC.

[0119] The x device typically supports non-3GPP access technologies such as WLAN or wired connections. The x device can also be replaced with other possible terms, such as end device or non-3GPP device, without limitation.

[0120] The x device can be an IoT device (such as a laptop), while the terminal device can be a mobile phone. The difference between the terminal device and the x device lies in their support for cellular access technology, NAS messaging modules, and SIM cards, thus enabling the terminal device to access the network. The x device, on the other hand, does not support cellular access technology, SIM cards, or non-3GPP access technologies, therefore it cannot directly access the network. However, the x device can establish a connection with the terminal device through non-3GPP access technologies and access the network through the terminal device. Non-3GPP access technologies include wireless local area network (WLAN) access technology, Bluetooth access technology, wired access technology, fixed-line access technology, and short-range access technologies.

[0121] Currently, the 5GC network assigns only one IP address or one range of IP addresses (i.e., multiple IP addresses) to a UE's Protocol Data Unit (PDU) session.

[0122] In scenarios where x devices need to access the data network through a UE (such as a CPE), the 5GC network typically allocates an IP address range for the PDU session.

[0123] For example, device x can establish a connection with UE through Wi-Fi, Bluetooth or other short-range wireless communication technologies, and access the network through UE. Then, device x obtains the IP address assigned to it by the network from the IP address range through UE, and uses the IP address to access the target data network.

[0124] The process by which the network side assigns an IP address to device x from the IP address range is as follows:

[0125] S101, when the UE initiates the PDU session establishment process, the SMF obtains the SM subscription data of the PDU session from the UDM.

[0126] The SM contract data includes IP address range information.

[0127] S102, after the UE's PDU session is established, the UE sends a Dynamic Host Configuration Protocol (DHCP) message to the UPF.

[0128] This DHCP message is used to request an IP address to be assigned to device x. The UE receives the DHCP message sent by device x connected to the UE and forwards the message to the UPF.

[0129] S103, the UPF forwards the DHCP message to the SMF, and in turn, the SMF receives the DHCP message from the UPF.

[0130] S104, the SMF selects an IP address from the IP address range corresponding to the PDU session and sends it to the UE via a DHCP message.

[0131] SMF sends the IP address to the UE along with the DHCP response (offer) message.

[0132] S105, the UE forwards the DHCP response message to device x.

[0133] The IP addresses assigned to PDU sessions by the 5GC are typically different, with each PDU session corresponding to a unique IP address to ensure that IP addresses from different PDU sessions do not conflict. Therefore, device x obtains IP address #1 from UE1's PDU session and uses IP address #1 to transmit service data to the data network via the UPF network element. Then, device x moves out of the signal coverage area of ​​UE1, thus disconnecting the connection with UE1 and entering the signal coverage area of ​​UE2, thus switching to UE2. After this, device x typically uses a different IP address (such as IP address #2) to transmit service data to the data network via the UPF network element. This causes the data network to perceive the change in IP address as a different device x, leading the data network to interrupt the IP connection previously established between device x and the data network for IP address #1. This may involve releasing the relevant configuration of that IP connection and negotiating a new IP connection with device x for IP address #2. The data network then uses the new IP connection to re-transmit service data, affecting the service reliability and continuity of device x.

[0134] Based on this, considering that after device x connects to UE2, it still uses IP address #1 for data transmission to avoid data network connection interruption. When the UPF network element receives a downlink data packet from the data network, and the destination address of the downlink data packet is IP address #1, it will still send the downlink data packet to the PDU session of UE1 corresponding to IP address #1 due to the one-to-one correspondence between PDU sessions and IP addresses. Since device x has switched from UE1 to UE2, it is no longer within the coverage area of ​​UE1, thus preventing device x from receiving downlink data packets through UE1, thereby affecting the reliability and continuity of services between device x and the data network.

[0135] To address the aforementioned technical problems, the embodiments of this application propose the following technical solutions.

[0136] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0137] In the embodiments of this application, "instruction" can include direct and indirect instructions, as well as explicit and implicit instructions. The information indicated by a certain piece of information is called the information to be instructed. In the specific implementation process, there are many ways to instruct the information to be instructed, such as, but not limited to, directly instructing the information to be instructed, such as the information to be instructed itself or its index. It can also indirectly instruct the information to be instructed by instructing other information, where there is a correlation between the other information and the information to be instructed. It can also instruct only a part of the information to be instructed, while the other parts are known or pre-agreed upon. For example, the instruction of specific information can be achieved by using a pre-agreed (e.g., protocol-defined) arrangement of various pieces of information, thereby reducing instruction overhead to some extent. At the same time, common parts of various pieces of information can be identified and uniformly indicated to reduce the instruction overhead caused by individually indicating the same information.

[0138] Furthermore, the specific instruction method can also be any existing instruction method, such as, but not limited to, the above-mentioned instruction methods and their various combinations. As described above, for example, when multiple pieces of information of the same type need to be indicated, the instruction methods for different pieces of information may differ. In the specific implementation process, the required instruction method can be selected according to specific needs. This application embodiment does not limit the selected instruction method. Therefore, the instruction methods involved in this application embodiment should be understood to cover various methods that enable the party to be instructed to obtain the information to be indicated.

[0139] It should be understood that the information to be indicated can be sent as a whole or divided into multiple sub-information messages sent separately, and the sending period and / or timing of these sub-information messages can be the same or different. The specific sending method is not limited in this application embodiment. The sending period and / or timing of these sub-information messages can be predefined, for example, according to a protocol, or configured by the sending node device by sending configuration information to the receiving node device.

[0140] In this application, "sending information" can be understood as one device sending information to another device, or it can also be understood as one logical module within a device sending information to another logical module. For example, "network device sending information" can be understood as a network device sending information to another device (such as a terminal or other network device), or it can be understood as logical module 1 in the network device sending information to logical module 2 in the network device.

[0141] In this application, "receiving information" can be understood as one device receiving information from another device, or it can also be understood as a logical module within a device receiving information from another logical module. For example, "network device receiving information" can be understood as a network device receiving information from another device (such as a terminal or other network device), or it can be understood as logical module 1 in the network device receiving information from logical module 2 in the network device.

[0142] In this application, phrases such as "sending information to... (e.g., a terminal)" or related illustrations in the accompanying drawings can be understood as indicating that the destination of the information is a terminal. This can include sending information directly or indirectly to a terminal. Similarly, phrases such as "receiving information from... (e.g., a terminal)," "receiving information from... (e.g., a terminal)," or "receiving information sent by (e.g., a terminal)," or related illustrations in the accompanying drawings, can be understood as indicating that the source of the information is a terminal. This can include receiving information directly or indirectly from a terminal. Information may undergo necessary processing between the source and destination, such as format changes, but the destination can understand the valid information from the source. Similar expressions in this application can be interpreted similarly and will not be elaborated further here.

[0143] "Predefined" or "pre-configured" can be achieved by pre-saving corresponding codes, tables, or other means that can be used to indicate relevant information in the device. This application does not limit the specific implementation method. "Saving" can refer to saving in one or more memories. These memories can be separate installations or integrated into the encoder, decoder, processor, or communication device. Alternatively, some memories can be separately installed, while others are integrated into the decoder, processor, or communication device. The type of memory can be any form of storage medium, and this application does not limit this.

[0144] The “protocol” mentioned in the embodiments of this application may refer to a protocol family in the field of communication, a standard protocol with a similar protocol family frame structure, or a related protocol applied to future communication systems. The embodiments of this application do not specifically limit this.

[0145] In the embodiments of this application, descriptions such as "when," "under the circumstances," "if," and "if" all refer to the device making corresponding processing under certain objective circumstances, and are not limited to a specific time. They do not require the device to make a judgment action during implementation, nor do they imply any other limitations.

[0146] In the description of the embodiments 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 the embodiments of this application is merely a description of 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 the embodiments 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., are not necessarily different. Furthermore, in the embodiments of this application, words such as "exemplary" or "for example" are used to indicate that something is being used as an example, illustration, or description. Any embodiment or implementation described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or implementations. Specifically, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner for ease of understanding.

[0147] The network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0148] To facilitate understanding of the embodiments of this application, the communication system applicable to the embodiments of this application will be described in detail first using the communication system shown in FIG4 as an example. For example, FIG4 is a schematic diagram of the architecture of a communication system to which the method provided in the embodiments of this application applies.

[0149] As shown in Figure 4, this communication system is mainly applicable to the aforementioned 5GS, and primarily includes the UE, user plane network elements, and data network. The UE can be found in the relevant descriptions of 5GS or 5G CPE, and will not be elaborated upon here. The user plane network elements can be the UPF network elements in 5GS, as detailed above, or network elements used in future communication systems to implement corresponding user plane functions; there are no specific limitations on these.

[0150] Optionally, the communication system may further include an x ​​device, which accesses the data network through a UE. The x device can switch connections between UEs, such as switching from a connection with UE1 to a connection with UE2, that is, switching from accessing the data network through UE1 to accessing the data network through UE2.

[0151] For example, Figure 5 is a schematic diagram of the network architecture provided in an embodiment of this application. As shown in Figure 5, UE1 and UE2 (i.e., the terminal devices mentioned above) belong to the same group, and AN1 (or RAN1) and AN2 (or RAN2) are access network devices, which can be the same access network device or different access network devices. UE1 and UE2 access the same 5GC core network. The access network devices can be referred to the relevant description in the above 5GS, and will not be repeated here.

[0152] In this context, a UE is in a group, which may include multiple UEs capable of accessing the first network. A group can be the aforementioned home group, meaning that one or more UEs (group members) in the group belong to the same home network. Alternatively, groups and group members within groups can also be divided based on information such as the UE's service information, the capabilities of the UE, the UE's geographical location, or network location, which is not limited here.

[0153] For example, a group is determined by service information related to the UE. The service information may be a data network name (DNN) and / or slice information. The slice information may be, for example, network slice selection assistance information (NSSAI). That is, a group is uniquely identified by the DNN and / or slice information. Different groups have different DNNs and / or slice information.

[0154] UEs can refer to the relevant introduction of terminal equipment in the 5GS section above, or to the 5G CPE section above, which will not be repeated here.

[0155] To ensure the reliability and continuity of services, the communication system offers two options:

[0156] Option 1: In this communication system, multiple sessions are associated with address ranges. The user plane network element transmits first service data through at least two of the multiple sessions associated with the address range. It can be understood that before the user plane network element receives the first service data, it establishes multiple corresponding sessions for each terminal in the group; that is, one terminal in the group corresponds to one session, which is used to transmit the service data of the second device. Since one terminal device in the group corresponds to one session, when the second device switches connections between any two terminal devices in the group, such as switching from a connection with terminal device 1 to a connection with terminal device 2, at least two sessions may include the sessions established by the user plane network element for both terminal device 1 and terminal device 2. Therefore, regardless of whether the second device is within the signal coverage area of ​​terminal device 1 or terminal device 2, it can still receive downlink service data packets through at least two sessions, thereby improving the service reliability of the second device. Furthermore, since the second device can promptly receive downlink service data packets when disconnecting from terminal device 1 and moving to the signal coverage area of ​​terminal device 2, the service reliability of the second device is guaranteed.

[0157] The second device can be an "x device," which is a device that does not support network access via 3rd Generation Partnership Project (3GPP) access technologies. The x device can be an IoT device (such as a laptop), while the terminal device can be a mobile phone. The difference between the terminal device and the x device is that the terminal device supports cellular access technology, NAS messaging modules, and SIM cards, thus enabling it to access the network. The x device does not support cellular access technology, does not support SIM cards, and supports non-3GPP access technologies, therefore it does not have the ability to directly access the network. However, the x device can establish a connection with the terminal device through non-3GPP access technologies and access the network through the terminal device. Non-3GPP access technologies include wireless local area network (WLAN) access technology, Bluetooth access technology, wired access technology, fixed network access technology, or short-range access technologies, etc.

[0158] Optionally, at least two sessions constitute multiple sessions. That is, for service data packets whose addresses belong to the address range of the group, they are transmitted in multiple sessions. Since multiple sessions are sessions established by multiple terminal devices within the group, when the second device switches connections between any two terminal devices within the group, such as switching from terminal device 1 to terminal device 2, it can be understood that the second device moves out of the signal coverage area of ​​the currently connected terminal device 1, thus disconnecting from terminal device 1 and moving to the signal coverage area of ​​terminal device 2 to establish a connection with terminal device 2. Therefore, the second device can still receive downlink service data packets through the session of terminal device 2, thereby improving the service reliability of the second device. Furthermore, since the second device can receive downlink service data packets in a timely manner when disconnecting from terminal device 1 and moving to the signal coverage area of ​​terminal device 2, the service reliability of the second device is guaranteed.

[0159] The address range can be the address range used by the service data of the terminal devices in the group, that is, the terminal devices in the group share the same address range. The address range can be the IP address range mentioned in 5GS, or it can be an address list. The address range can include multiple addresses, whether non-contiguous or contiguous. For details on multiple terminal devices, please refer to the relevant introduction of terminal devices in 5GS, or the 5G CPE mentioned above. It will not be elaborated here.

[0160] Option 2: In this communication system, the user plane network element determines that the address of the first user equipment is updated from being associated with the first session (the session of UE1) to being associated with the second session (the session of UE2). That is, it determines that the first user equipment is switched from being connected to the second user equipment to being connected to the third user equipment. Therefore, when the user plane network element receives the first data of the service from the data network, since the service is associated with the address of the first user equipment, or in other words, the destination address of the first data of the service is the address of the first user equipment, the user plane network element associates the first user equipment with the second session according to the address of the first user equipment and transmits the first data through the second session.

[0161] In this way, when the first user equipment moves between different terminal equipment in the group, the service data can be transmitted to the terminal equipment (i.e., the third user equipment) connected to the first user equipment while keeping the address of the first user equipment unchanged, and then transmitted to the first user equipment to support communication between the first user equipment and the data network, thereby improving the service reliability of the first user equipment.

[0162] The first user equipment can be the aforementioned device x. The first user equipment does not support 3GPP access technology for network access, or in other words, it lacks the capability for 3GPP access. Alternatively, the first user equipment can support non-3GPP access technology for network access, meaning it has the capability to access the network via non-3GPP access technologies. This network can be a mobile communication network, such as if the first user equipment needs to access the network through a second or third user equipment.

[0163] The first user equipment is not usually understood as a terminal in the conventional sense, or in other words, the first user equipment is a different device from the second / third user equipment mentioned above.

[0164] The second and third user equipment (User Equipment) can be terminal devices included in the same group, where the devices in the group support 3GPP access technology to access the network. That is, the second and third user equipment support 3GPP access technology to access the network. The second and third user equipment can refer to the terminal devices in the aforementioned 5GS, or to UE1 and UE2 in the same group in Figure 5. The group may also include other devices / terminals besides the second and third user equipment; this application does not impose any restrictions on this.

[0165] The interaction process between various network elements / devices in the above-described communication system will be specifically described below with reference to Figures 6-9 through method embodiments. The communication method provided in this application embodiment can be applied to the above-described communication system and specifically applied to various scenarios / processes mentioned in the above-described communication system, which will be described in detail below.

[0166] Option 1:

[0167] Figure 6 is a schematic flowchart of the communication method provided in an embodiment of this application. This communication method is applicable to the aforementioned communication system and mainly involves the interaction between terminal devices, user plane network elements, and data networks. It should be understood that descriptions such as "first" and "second" are used at the granularity of the embodiments. For example, the information referred to by "first device" and "second device" in the embodiments of this application applies to Figures 6-7.

[0168] As shown in Figure 6, the flow of this communication method is as follows:

[0169] S601, the user plane network element receives the first service data from the data network.

[0170] The first service data can be downlink data sent by the data network in response to the uplink data. For example, after the data network receives an uplink data packet with a source IP address of IP address #1, it sends a downlink data packet with a destination IP address of IP address #1 to the user plane network element, so that the user plane network element receives the downlink data packet from the data network.

[0171] S602, if the destination address of the first service data belongs to the address range associated with multiple sessions, the user plane network element transmits the first service data to at least two terminal devices through at least two of the multiple sessions.

[0172] It is understood that, unless otherwise specified, the terminal devices mentioned below can be understood as UEs within the group.

[0173] Multiple sessions can be sessions established by user plane network elements for the second device. The second device accesses the first network through a terminal device, and the first network can be 5GC. The second device can refer to the description of device x above, and will not be repeated here.

[0174] It can be understood that multiple sessions refer to user plane network elements establishing corresponding sessions for multiple terminal devices in a group, used to transmit service data of the second devices. Therefore, these are called sessions established by user plane network elements for the second devices, and multiple sessions may be shared by multiple second devices. For example, the session management network element can select the same user plane network element to establish sessions for multiple terminal devices; see the relevant introduction below for details. In multiple sessions, one terminal device can correspond to at least one session. A session can be a PDU session or any other possible session, such as sessions in future communication networks. Multiple sessions can be identified by the same DNN and / or slice information, or in other words, multiple sessions share the same DNN and / or slice information. Alternatively, multiple sessions can be considered as associated with the same service corresponding to the same DNN and / or slice information; that is, the services associated with multiple sessions can be the same.

[0175] For example, a user plane network element establishes PDU session #1 for UE #1 in the group, PDU session #2 for UE #2 in the group, and PDU session #3 for UE #3 in the group. The DNN and / or slice information of PDU session #1, PDU session #2, and PDU session #3 are the same, that is, the services related to PDU session #1, PDU session #2, and PDU session #3 are the same, so multiple sessions can include PDU session #1, PDU session #2, and PDU session #3.

[0176] When establishing a session, the user plane network element can determine whether the session is for a terminal device within a group. For example, the session management network element sends an N4 message to the user plane network element. The N4 message carries session-related configuration information, which may include group information. Thus, the user plane network element knows that the session is for a terminal device within the group. Ultimately, the user plane network element can identify the multiple sessions associated with the group.

[0177] In addition, when multiple terminal devices establish the aforementioned multiple sessions, they obtain their addresses from the address range of the group. These addresses are used to transmit service data from multiple terminal devices, as detailed below. The session management network element can be the SMF network element in the aforementioned 5GS (refer to the relevant description above), or a network element in a future communication system used to implement session management functions; there are no specific limitations on this.

[0178] It is understood that the aforementioned multiple sessions refer to sessions associated with multiple terminal devices and a group. User plane network elements can also establish other sessions for multiple terminal devices, and this application embodiment does not impose any limitations. For example, if session #1 and session #2 are established for terminal device #1 within the group, and session #3 is established for terminal device #2 within the group, where session #1 and session #3 are sessions with the same DNN and / or slice information as the group, that is, session #1 and session #3 are sessions associated with the group, then the aforementioned multiple sessions may include session #1 and session #3. Unless otherwise specified, the sessions mentioned below can be understood as sessions associated with the group.

[0179] An address range is the range of addresses used by multiple terminal devices in a group for their service data transmission. In other words, multiple terminal devices use addresses within this address range to transmit service data. Alternatively, when establishing multiple sessions, the terminal devices in the group obtain their addresses from this address range; that is, the sessions of multiple terminal devices in the group share the group's address range. The address range can be a range of network addresses or physical addresses, such as IP addresses or media access control (MAC) addresses.

[0180] It should be understood that the address range can be replaced with any possible expression, such as an address segment, without limitation. For ease of explanation, the following text uses an IP address range as an example.

[0181] An IP address range can include at least one Internet Protocol version 4 (IPv4) address and / or an Internet Protocol version 6 (IPv6) address. An IP address range can be expressed as an IP address and a subnet mask; for example, an IPv6 address range can include an IPv6 prefix and / or a subnet mask. For instance, an IPv4 address range might be 192.168.1.0 with a subnet mask of 255.255.255.0. An IP address range can also be a list of IP addresses, which can include multiple IP addresses, whether non-contiguous or contiguous. Other possible representations of an IP address range include IP ranges.

[0182] In this embodiment, the user plane network element receives first service data from the data network and obtains the address of the first service data, wherein the address of the first service data may be a destination address, such as IP address #1. The user plane network element determines that the destination address belongs to the address range of a group, that is, the address range of the group includes the destination address, thereby determining multiple sessions associated with the address range, and transmitting downlink data packets to at least two terminal devices in the group through at least two of the multiple sessions. Optionally, the user plane network element transmits downlink data packets through multiple sessions.

[0183] For example, a UPF network element receives downlink data packets from a data network and obtains the address of the downlink data packet, which can be a destination address, such as IP address #1. The UPF network element determines that IP address #1 belongs to the IP address range of a group, that is, the IP address range of the group includes IP address #1, thereby identifying multiple PDU sessions associated with the IP address range of the group, and transmitting downlink data packets to at least two terminal devices in the group through at least two of the multiple PDU sessions. Optionally, the UPF network element transmits downlink data packets through multiple PDU sessions, that is, the UPF network element transmits downlink data packets through each of the multiple PDU sessions.

[0184] The address range and the association between multiple sessions can be determined by the user plane network element itself, or indicated by other network elements.

[0185] Address ranges can be pre-configured in data management network elements (such as UDM network elements), or in the session management (SM) subscription data of terminal devices. The session management network element obtains the group identifier corresponding to the session and the address range of the group from the subscription data corresponding to the session or terminal device. For example, the SMF network element obtains UE1's SM subscription data from the UDM network element. The SM subscription data contains the identifier information of the group to which UE1 belongs and the group's IP address range. The session management network element then sends the address range to the user plane network element. Thus, the user plane network element can determine the association relationship between the address range and multiple sessions based on the association between sessions established by each terminal device and the address range.

[0186] The session management network element can also indicate to the user plane network element the association between address ranges and multiple sessions. The user plane network element receives a first message from the session management network element, which may include indication information for mapping address ranges to multiple sessions. Based on the indication information, the user plane network element saves the mapping relationship between address ranges and multiple sessions, and the mapping relationship is used to identify multiple sessions.

[0187] The first message can be an N4 message. This information instructs user plane network elements that they need to associate an address range with multiple sessions. The first message can include N4 messages generated by multiple terminal devices within a group when establishing a session.

[0188] For example, when UE1 establishes a PDU session within the group, the UPF network element receives N4 message #1 from the SMF network element. N4 message #1 includes information indicating that the address range corresponds to UE1's session. When UE2 establishes a PDU session within the group, the UPF network element receives N4 message #2 from the SMF network element. N4 message #2 includes information indicating that the address range corresponds to UE2's session. The first message is N4 message #1 and / or N4 message #2, and the multiple sessions include UE1's session and UE2's session.

[0189] Optionally, the indication information may include information on multiple sessions and / or address ranges, instructing the user plane network element to map the address ranges to multiple sessions.

[0190] Optionally, the indication information may also include group identification information, which may be information that can uniquely identify the group, such as a group identifier, or at least one of DNN and slice information, wherein the slice information may be, for example, NSSAI.

[0191] The group identification information can be used to select the same session management network element and user plane network element for terminal devices in the same group when establishing a session. For example, when UE1 and UE2 establish a PDU session in the group, the AMF network element selects the same SMF network element for UE1 and UE2 based on the group identification information.

[0192] Similarly, the SMF network element selects the same UPF network element for UE1 and UE2 based on the group identification information. The group identification information can also be used to associate multiple sessions. Subsequently, user plane network elements can determine the multiple sessions corresponding to the group identification information by knowing that the destination address of the first service data belongs to an address range and that the address range is associated with the group identification information.

[0193] If the destination address of the first service data falls within the address range, the user plane network element determines multiple sessions corresponding to the address range based on the correspondence, and transmits the first service data to the terminal device through at least two of the multiple sessions.

[0194] After the user plane network element stores the mapping between address ranges and multiple sessions, when the user plane network element receives the first service data, it can determine multiple sessions through the mapping between address ranges and multiple sessions. Then, it can send the first service data to at least two terminal devices through at least two sessions corresponding to the address ranges of the group. Therefore, when device x switches connections between any two terminal devices in the group, such as switching from a connection with terminal device 1 to a connection with terminal device 2, the at least two sessions may include the sessions established by the user plane network element for terminal device 1 and terminal device 2. Therefore, regardless of whether device x is within the signal coverage area of ​​terminal device 1 or terminal device 2, it can still receive downlink service data packets through at least two sessions, thereby improving the service reliability of device x.

[0195] Furthermore, since device x can receive downlink service data packets in a timely manner when it disconnects from terminal device 1 and moves to the signal coverage area of ​​terminal device 2, the service reliability of device x is guaranteed.

[0196] Optionally, the user plane network element transmits the first service data to at least two terminal devices through at least two of the multiple sessions. This can include: the user plane network element replicating the first service data into multiple copies, and transmitting one copy of the first service data to the terminal device through each of the multiple sessions. In other words, the user plane network element replicates the first service data into multiple sessions, and one copy of the first service data is transmitted in each of the multiple sessions. As a result, at least one copy of the first service data will be transmitted to the terminal device connected to device x through the session, and can then be sent to device x, ensuring service reliability.

[0197] In summary, the user plane network element establishes sessions with address ranges for multiple terminal devices in a group. The user plane network element transmits first service data through at least two of these sessions associated with the address range. Since one terminal device corresponds to one session in the group, when device x switches connections between any two terminal devices in the group, such as switching from connection to terminal device 1 to connection to terminal device 2, at least two sessions may include those established by the user plane network element for both terminal device 1 and terminal device 2. Therefore, regardless of whether device x is within the signal coverage area of ​​terminal device 1 or terminal device 2, it can still receive downlink service data packets through at least two sessions, thereby improving the service reliability of device x. Furthermore, since device x can receive downlink service data packets promptly when it disconnects from terminal device 1 and moves to the signal coverage area of ​​terminal device 2, the service reliability of device x is also guaranteed.

[0198] If a copy of the first service data is transmitted in each of multiple sessions, at least one copy of the first service data will be transmitted to the terminal device connected to device x through the session, and then sent to device x, ensuring the service reliability of device x.

[0199] The following describes the process of transmitting downlink data by terminal devices in a group.

[0200] In one possible implementation, the communication method may further include: a first device receiving first service data from a user plane network element, determining the second device corresponding to the destination address of the first service data based on the correspondence between the source address of the second service data and the second device, and sending the first service data to the second device. Wherein, the source address of the second service data is the same as the destination address of the first service data.

[0201] The first device can be a terminal device in a group, which includes multiple devices capable of accessing the first network, and these multiple devices include the first device, meaning the first device has the capability to access the first network. The second device accesses the first network through a device in the group, that is, through a terminal device capable of accessing the first network, such as the aforementioned device x.

[0202] The second service data can be uplink data involving the same service as the first service data. For example, the second service data is an uplink data packet from device x, and the first service data is a downlink data packet involving the same service as the second service data.

[0203] For example, the first device pre-stores the correspondence between the source address of the second service data and the second device. Since the source address of the second service data is the same as the destination address of the first service data, the first device determines that the first service data corresponds to the second device, and then sends the second service data to the second device.

[0204] For example, UE1 receives an uplink data packet from device x, where the source address of the uplink data packet is device x's IP address #1. UE1 stores the mapping between device x and IP address #1. Subsequently, when UE1 receives a downlink data packet from a UPF network element, since the destination address of the downlink data packet is IP address #1, UE1 can look up the mapping between device x and IP address #1 to find the device x corresponding to IP address #1, and then send the downlink data packet to device x.

[0205] In this way, when the second device is connected to the data network through the first device, the second device can receive the first service data through the first device, thus ensuring the reliability of the service between the second device and the network side.

[0206] The following is optional. For the sovereign implementation, the behavior of the user plane network element and its supporting network element is mandatory, while the terminal device sending uplink data is optional.

[0207] The above describes the downlink data transmission process. The following describes the uplink data transmission process of terminal devices in the group. S1-S2 are optional steps.

[0208] S1, the first device receives second service data from the second device.

[0209] S2, if the address range of the group includes the address of the second service data, the first device sends the second service data to the user plane network element through the session corresponding to the group.

[0210] The address of the second service data can be the source address of the second service data, such as the source IP address. The first device obtains the source address of the second service data and determines whether the source address belongs to the address range of the group. If so, the first device sends the second service data to the user plane network element through the session corresponding to the group. The session corresponding to the group can be at least one of multiple sessions corresponding to the address range of the group, and the session is the session of the first device.

[0211] The correspondence between the address range of the group and the session can be referenced in S602, where the correspondence between the address range and multiple sessions is used. The session in S2 can be one or more sessions of the first device among the multiple sessions mentioned above.

[0212] It is understandable that by associating the address of the second service data with the address range of the group, the session corresponding to the address range of the group can be matched. In this way, the first device can match the session related to the second service data, or in other words, match the session related to the service involved in the second service data, thus ensuring the reliability of the first device in transmitting the second service data.

[0213] S1-S2 can be executed before or after S601. If S1-S2 can be executed before S601, the first business data can be the response data to the second business data.

[0214] Optionally, before the first device receives the second service data from the second device, the communication method may further include: the first device receiving a second message from a session management network element, the second message indicating that the session has been successfully established, the second message including the address range of the group corresponding to the session, the first device storing the correspondence between the address range of the session and the group according to the second message, the correspondence between the address range of the session and the group being used to determine the session corresponding to the group.

[0215] The second message can be a message indicating successful session establishment received when the first device establishes a session, such as a PDU session establishment success response message sent by the SMF network element in response to the PDU session establishment request.

[0216] The second message can also be received through the access and mobility management network element. That is, the session management network element sends the second message to the access and mobility management network element, and then the access and mobility management network element forwards the second message to the first device, so that the first device receives the second message.

[0217] The access and mobility management network element can be the AMF network element in the aforementioned 5GS, as detailed in the above introduction, or a network element used in future communication systems to implement the corresponding functions of access and mobility management, without any limitation.

[0218] The second message can be carried in the downlink NAS transmission message, carrying the address range of the group corresponding to the session, such as the PDU session of UE1 corresponding to the IP address range of the group to which UE1 belongs.

[0219] The second message implicitly instructs the first device to map the address range of the session to the address range of the group. Alternatively, the second message may also contain instruction information for indicating that the address range of the session to the address range of the group be mapped, for explicitly instructing the first device to associate and store the address range of the session to the address range of the group, so that the first device stores the mapping relationship between the address range of the session and the group according to the second message.

[0220] For example, the SMF network element sends a PDU session establishment success response message to the AMF network element, and then the AMF network element sends a downlink NAS transmission message to UE1. This downlink NAS transmission message carries the PDU session establishment success response message. UE1 belongs to group #1, and UE1 stores the IP address range information of group #1 corresponding to PDU session #1.

[0221] In this way, the first device stores the correspondence between the address range of the session and the group according to the second message. When the first device receives the second service data from the second device, it can determine the session corresponding to the group through the correspondence between the address range of the session and the group, and send the second service data to the user plane network element, thus ensuring the reliability and continuity of the second device's service.

[0222] The following describes the process by which the session management network element assigns an address to the second device in the implementation of this application.

[0223] In one possible implementation, the communication method may further include: when the first device establishes a connection with the second device, the first device obtains the address assigned to the second device from the session management network element and sends the address assigned to the second device by the session management network element to the second device.

[0224] The address range of the group includes the addresses allocated to the second device by the session management network element. In other words, the session management network element allocates addresses to the second device from the address range of the group. The address allocated to the second device includes the address of the second service data. That is, the second device subsequently uses the address allocated to it by the session management network element as the source address for encapsulating the second service data and transmitting it.

[0225] In this way, the second device always uses the address assigned to it by the session management network element to transmit service data, so that when the data network receives service data, it always recognizes that it is the same device accessing the network, thus avoiding data network connection interruption and ensuring service continuity between the second device and the data network.

[0226] Optionally, when the first device receives a request message from the second device, it obtains the address assigned to the second device from the session management network element. The request message may be a DHCP request message, used to request the network side to assign an address to the second device.

[0227] The overall flow of the communication method of Scheme 1 provided in the embodiments of this application has been illustrated above with reference to Figure 6. The specific flow of the communication method of Scheme 1 provided in the embodiments of this application in a specific scenario is described below with reference to Figure 7.

[0228] Figure 7 is a schematic flowchart of the communication method provided in this embodiment. This communication method is applicable to the above-mentioned communication system and specifically involves the interaction between UPF network elements (i.e., user plane network elements), UE1 and UE2 (i.e., terminal devices in the group), x device (i.e., second device), AMF / SMF network elements, and UDM network elements.

[0229] After the UPF network element receives downlink data packets from the data network, if the destination address of the downlink data packet belongs to an address range associated with multiple sessions, the UPF network element transmits the downlink data packet to the terminal devices in the group through multiple sessions. This allows the x device to move between different terminal devices in the group, transmitting downlink data packets through multiple sessions associated with the address range. This ensures that the downlink data packet can be transmitted to the terminal devices connected to the x device while keeping the address used by the x device unchanged, and then to the x device itself. This supports communication between the x device and the data network, thereby maintaining the service reliability of the x device.

[0230] Specifically, as shown in Figure 7, the communication method flow is as follows:

[0231] S700, UDM network element extends UE session subscription data.

[0232] Session subscription data can be SM subscription data. The UDM network element adds group identifier information and group IP address range information to the UE's SM subscription data. The group identifier information indicates the group to which this session belongs. The group identifier information can be a group identifier, or at least one of a data network name (DNN) and slice information. The slice information can be, for example, NSSAI, meaning a group is uniquely identified using a DNN and / or slice information. Different groups have different DNNs and / or slice information.

[0233] The IP address range information for the group can be found in the description in S602, and will not be repeated here.

[0234] S701, UE1 initiates the registration process to 5GC.

[0235] UE1 sends a registration request message to the access network device, which forwards the message to the AMF network element. The AMF network element obtains UE1's subscription data and performs authentication on UE1 based on the subscription data.

[0236] S702, UE1 sends a first session establishment request message to the SMF network element through the AMF network element.

[0237] The first session establishment request message is used to request the establishment of PDU session #1. The first establishment request message can be carried in an uplink NAS transport (UL NAS transport) message, that is, UE1 sends an uplink NAS transport message to the AMF network element, which carries the first session establishment request message. The AMF forwards the first session establishment request message to the SMF network element.

[0238] S703, the SMF network element obtains the subscription data corresponding to PDU session #1 from the UDM network element.

[0239] The subscription data corresponding to PDU session #1 can be the subscription data corresponding to the DNN and / or slice information of PDU session #1, that is, the SM subscription data of UE1.

[0240] The SMF network element sends a subscription data request message to the UDM network element. This message requests UE1's SM subscription data and may include UE1's subscription permanent identifier (SUPI). The UDM network element can then query UE1's SM subscription data based on UE1's SUPI and send this data to the SMF network element. UE1's SM subscription data includes at least one of the following: group identifier information for PDU session #1, group IP address range information, and UE1's SUPI information.

[0241] Optionally, UE1's SM subscription data includes an address sharing indication. This indication is used to specify that a group IP address range is shared by UEs within the group. Specifically, when UEs in the group establish a PDU session with the same DNN and / or slice information, their IP address is obtained from this IP address range. For example, when UE1 in the group establishes PDU session #1 with slice information NSSAI#1, its IP address #2 is obtained from this IP address range. Similarly, when UE2 in the group establishes PDU session #2 with slice information NSSAI#1, its IP address #3 is obtained from this IP address range.

[0242] S704, the SMF network element sends a second session establishment request message to the UPF network element.

[0243] The Second Session Establishment Request message is used to request the establishment of a Packet Forwarding Control Protocol (PFCP) session between an SMF network element and a UPF network element. This message can be carried within an N4 message; that is, the SMF network element sends an N4 message to the UPF network element, which includes the Second Session Establishment Request message. The Second Session Establishment Request message may contain group identification information and IP address range information. Optionally, it may also contain an address sharing indication.

[0244] S705, UPF network element storage first correspondence.

[0245] The UPF network element stores the correspondence between PDU session #1 and the IP address range information of the group as the first correspondence. When a UE in the group establishes a PDU session with the same DNN and / or slice information as PDU session #1, the UPF network element adds a new PDU session corresponding to the IP address range information in the first correspondence.

[0246] For example, UE2 in the group establishes PDU session #2 with the same DNN and / or slice information as PDU session #1. The UPF network element adds the IP address range information corresponding to PDU session #1 and PDU session #2 in the first correspondence. That is to say, the correspondence between multiple PDU sessions in the group and the IP address range of the group is the first correspondence. Among them, multiple PDU sessions in the group can be PDU sessions of multiple UEs in the group, such as PDU session #1 of UE1, PDU session #2 of UE2, etc.

[0247] S706, the UPF network element sends a second session establishment response message to the SMF network element.

[0248] The second session can be a PFCP session, meaning the response message for establishing the second session can be a message indicating that the PFCP session has been successfully established.

[0249] S707, the SMF network element sends a PDU session #1 establishment success response message to the AMF network element.

[0250] The PDU session establishment success response message contains the IP address range information of the group corresponding to PDU session #1.

[0251] S708, the AMF network element sends a PDU session #1 establishment success response message to UE1.

[0252] The AMF network element sends a downlink NAS transmission message to UE1, which carries a PDU session #1 establishment success response message. At this point, the PDU session #1 establishment process for UE1 is complete. In addition, UE1 stores the IP address range information corresponding to PDU session #1.

[0253] The above describes the registration process and PDU session establishment process for UE1 to register with the network side. The registration process and PDU session establishment process for other UEs in the group can refer to the registration process and PDU session establishment process for UE1. For example, if UE2 in the group registers with the network side and establishes a PDU session #2 with the same DNN and / or slice information as UE1 (not shown in Figure 7), the specific process can be referred to S701 to S706, which will not be elaborated here.

[0254] The following is the process for the network side to assign an IP address to device x.

[0255] S709, device x sends a DHCP request message to UE1.

[0256] The DHCP request message is used to request an IP address to be assigned to device x by the network side.

[0257] It is understandable that when device x connects to UE1, device x sends a DHCP request message to UE1, that is, device x initiates the process of obtaining an IP address.

[0258] Device X may initiate the IP address acquisition process when it first connects to the terminal device (UE1), or it may initiate the IP address acquisition process when it first connects to the terminal device within a preset time period. In other words, device X initiates the IP address acquisition process when it first connects to the terminal device (UE1) for a certain service. That is to say, UE1 is the terminal device that device X connects to first. If device X connects to UE2 before UE1, device X will send a DHCP request message to UE2.

[0259] Alternatively, device x could initiate an IP address acquisition process when it needs to access the data network through a terminal device.

[0260] In summary, device x can send a DHCP request message to UE1 to request an IP address assigned by the network side even if it has not obtained an IP address.

[0261] S710, UE1 sends a DHCP message to the UPF network element.

[0262] S711, the UPF network element forwards DHCP messages to the SMF network element.

[0263] DHCP messages can be carried within N4 messages. In other words, when a UPF network element sends an N4 message to an SMF network element, the N4 message carries the DHCP message.

[0264] S712, SMF network element selects IP address #1.

[0265] The SMF network element assigns an IP address to device x. The SMF network element selects an IP address from the IP address range of the group corresponding to PDU session #1, such as selecting IP address #1 to assign to device x.

[0266] S713, the SMF network element sends a DHCP response message to the UPF network element.

[0267] DHCP response messages can be carried within N4 messages. A DHCP reply message contains the IP address #1 assigned to device x by the SMF network element.

[0268] S714, the UPF network element sends a DHCP response message to UE1.

[0269] S715, UE1 sends a DHCP response message to device x, and device x receives the DHCP response message accordingly.

[0270] Device x obtains IP address #1 assigned by the network side from the DHCP response message. Subsequently, device x uses IP address #1 as the source IP address to encapsulate uplink data packets.

[0271] S716, UE1 stores the second correspondence.

[0272] The second mapping is the mapping between IP address #1 and device x. UE1 can obtain the IP address #1 assigned to device x by the SMF network element by parsing the DHCP response message and save the mapping between IP address #1 and device x. Alternatively, UE1 can obtain the IP address #1 corresponding to device x from the source IP address of the uplink data packets subsequently sent by device x and store the mapping between IP address #1 and device x.

[0273] The execution order of S716 and S715 is not limited; that is, S716 can be executed before or after S715. If UE1 obtains the IP address #1 corresponding to device x from the source IP address of the uplink data packet subsequently sent by device x, and stores the correspondence between IP address #1 and device x, then S716 will be executed after S715.

[0274] The following describes the service process after device x switches from connecting to UE1 to connecting to UE2.

[0275] After the S717x device switches from connecting to UE1 to connecting to UE2, it sends uplink data packets to UE2.

[0276] Device x continues to use the previous IP address #1 to send uplink data packets.

[0277] S718, UE2 stores the second correspondence.

[0278] UE2 obtains the IP address #1 corresponding to device x from the source IP address of the uplink data packet and stores the correspondence between IP address #1 and device x.

[0279] S719, UE2 sends uplink data packets to the UPF network element, and correspondingly, the UPF network element receives uplink data packets from UE2.

[0280] UE2 stores the mapping between the group's IP address range and PDU session #2. Specifically, refer to S706 where UE1 stores the mapping between the group's IP address range and PDU session #1. That is, during the PDU session establishment process of UE2, UE2 stores the mapping between the group's IP address range and UE2's PDU session #2. Therefore, based on the source IP address of the uplink data packet being IP address #1, and IP address #1 belonging to the group's IP address range, UE2 determines the PDU session #2 corresponding to the IP address range. In other words, the PDU session corresponding to this uplink data packet is PDU session #2, and then sends the uplink data packet to the UPF network element through this PDU session #2.

[0281] The execution order of S719 and S718 is not limited; that is, S719 can be executed before or after S718.

[0282] In the S720, the UPF network element sends uplink data packets to the data network.

[0283] S721, the data network sends downlink data packets to the UPF network element, and correspondingly, the UPF network element receives downlink data packets from the data network.

[0284] A downlink data packet can be a downlink data packet sent by the data network in response to an uplink data packet, and the destination IP address of the downlink data packet is IP address #1.

[0285] In S722, the UPF network element transmits downlink data packets through multiple PDU sessions corresponding to the IP address range of the group.

[0286] UPF obtains the destination IP address of the downlink data packet, i.e., IP address #1. UPF determines that the destination IP address belongs to the IP address range of the group, and then determines multiple PDU sessions corresponding to the IP address range of the group through a first mapping relationship, which can be referred to in S704. For example, multiple PDU sessions may include PDU session #1 and PDU session #2 corresponding to the IP address range of the group, or they may include all PDU sessions corresponding to the IP address range of the group.

[0287] The UPF network element transmits downlink data packets across multiple PDU sessions corresponding to the IP address range of the group. For example, the UPF network element copies downlink data packets to all PDU sessions corresponding to the IP address range of the group and transmits the downlink data packets in each PDU session. Therefore, UEs corresponding to multiple PDU sessions, such as UE1 and UE2, will both receive downlink data packets with a destination IP address of IP address #1.

[0288] It is understandable that S721-S722 can be executed before S717. In other words, S721-S722 can be executed before device x switches from being connected to UE1 to being connected to UE2. That is, regardless of whether device x switches or which UE in the group is connected to device x, the steps of executing S721-S722 can send downlink data packets to the UE connected to device x through multiple PDU sessions corresponding to the IP address range of the group, thereby sending them to device x.

[0289] S723, after UE1 receives a downlink data packet from the UPF network element, it discards the downlink data packet.

[0290] Since device x has switched from connecting to UE1 to connecting to UE2, UE1 cannot send downlink data packets to device x, therefore, the downlink data packets are discarded.

[0291] S724, after UE2 receives the downlink data packet from the UPF network element, it determines the x device corresponding to the downlink data packet.

[0292] UE2 receives a downlink data packet with a destination IP address of IP address #1 and determines the x device corresponding to IP address #1 based on the correspondence. The correspondence can be referred to in S718, where UE2 stores the correspondence between IP address #1 and x device, and will not be elaborated here.

[0293] S725, UE2 sends downlink data packets to device x, and correspondingly, device x receives downlink data packets from UE2.

[0294] Thus, after the UPF network element receives downlink data packets from the data network, if the destination address of the downlink data packet belongs to an address range associated with multiple sessions, the UPF network element transmits the downlink data packet to the terminal devices in the group through multiple sessions. This allows the x device to move between different terminal devices in the group, transmitting downlink data packets through multiple sessions associated with the address range. This ensures that the downlink data packet can be transmitted to the terminal devices connected to the x device while keeping the address used by the x device unchanged, and then to the x device itself. This supports communication between the x device and the data network, thereby maintaining the service reliability of the x device.

[0295] Option 2:

[0296] Figure 8 is a schematic flowchart of the communication method provided in an embodiment of this application. This communication method is applicable to the above-mentioned communication system and mainly involves the interaction between terminal equipment, user plane network elements, and data network.

[0297] As shown in Figure 8, the flow of this communication method is as follows:

[0298] S801, the user plane network element determines that the address of the first user equipment is updated from being associated with the first session to being associated with the second session.

[0299] The first session is a session for the second user device, and the second session is a session for the third user device. The second user device and the third user device are included in the same group. There can be one or more first sessions and one or more second sessions, which is not limited here.

[0300] The terminal devices in the group have the ability to access the first network, which can be 5GC. In other words, the second and third user devices have the ability to access 5GC.

[0301] The first user equipment (UE) accesses the first network through devices in the group. This first UE is the same as the second device in S601-S602, for example, it could be an x ​​device or an end device. The second and third UEs can be referred to as the end devices in S601-S602, i.e., the UE. The group can be referred to in the description in S601-S602, and will not be repeated here.

[0302] S802, when the user plane network element receives the first data from the data network, the user plane network element associates with the second session based on the address of the first user equipment, and transmits the first data to the third user equipment through the second session.

[0303] In this context, the aforementioned service is associated with the address of the first user equipment (User Equipment), or in other words, the first data of the service is associated with the address of the first User Equipment (User Equipment). For example, the destination address of the first data of the service is the address of the first User Equipment (User Equipment). The address of the first User Equipment (User Equipment) can be an address allocated to the first User Equipment (User Equipment) from the address range of the group by the second User Equipment (User Equipment) or a user plane network element. The specific allocation method is described below and will not be elaborated further.

[0304] The S801 will be described in detail below.

[0305] The user plane network element determines that the address of the first user equipment, which was originally associated with the session of the second user equipment (first session), has been updated to be associated with the session of the third user equipment (second session). In other words, the user plane network element determines that the first user equipment has switched from being connected to the second user equipment to being connected to the third user equipment.

[0306] The following describes two specific methods for user plane network elements to determine the session update associated with the address of the first user equipment.

[0307] Method 1:

[0308] In one possible implementation, the user plane network element receives first information sent from a second user equipment and / or a third user equipment, the first information indicating second session information and the address of the first user equipment; S801 may include: the user plane network element determining, based on the first information, that the address of the first user equipment is updated from being associated with the first session to being associated with the second session.

[0309] The first information can be sent using existing signaling. For example, the first information can be carried in a PMF request message. For instance, the UPF network element receives a PMF request message from UE1 (second user equipment) and / or UE2 (third user equipment). The PMF request message includes the session information of UE2 and the IP address #1 of device x, thereby the UPF network element determines that device x, which was originally connected to UE1, will switch to establish a connection with UE2. The first information can also be sent by adding new signaling, decoupling it from existing signaling, which is not limited here.

[0310] The first information indicates the second session (the session of the third user equipment) information and the address of the first user equipment, which implicitly indicates that the second session is associated with the address of the first user equipment, that is, the third user equipment establishes a connection with the first user equipment.

[0311] Optionally, the first information is also used to indicate the correspondence between the second session information and the address of the first user equipment. The second session information may be identification information of the second session, such as DNN, NSSAI, or other information that uniquely identifies the second session, or it may be the identification of the third user equipment, such as the UE S1 application protocol identity (UE S1AP ID), international mobile subscriber identity (IMSI), SUPI, etc., without limitation.

[0312] The first information may be information reported in real time by the second user equipment and / or the third user equipment. For example, when the second user equipment connects to the first user equipment, the second user equipment sends the first information to the user plane network element. Or, when the second user equipment connects to the first user equipment, the second user equipment reports the address of the first user equipment to the third user equipment, thereby the first user equipment reports the first information to the user plane network element.

[0313] Furthermore, if a user plane network element receives first information sent from a third user equipment, the first information may only indicate the address of the first user equipment without indicating the second session information, thus implicitly indicating that the second session is associated with the address of the first user equipment, that is, the third user equipment is connected to the first user equipment.

[0314] Optionally, the user plane network element stores the correspondence between the address of the first user equipment and the second session based on the first information.

[0315] As can be seen, in Method 1, if the second user equipment sends uplink data to the user plane network element while connected to the first user equipment, and then the first user equipment switches to connect to the third user equipment before the user plane network element receives downlink data from the data network in response to the uplink data, the user plane network element can determine the address of the first user equipment and its association with the second session through the first information. In this way, the user plane network element can promptly determine the update status of the address association session of the first user equipment, so that the user plane network element can transmit the first data on the accurate path (second session) and ensure the reliability of the first user equipment's services.

[0316] Method 2:

[0317] In another possible implementation, the communication method may further include: the user plane network element receiving second data from a third user equipment and obtaining the source address of the second data. S801 may further include: the user plane network element determining, based on the fact that the source address of the second data is the same as the address of the first user equipment, that the address of the first user equipment is updated from being associated with a first session to being associated with a second session.

[0318] It is understandable that the second data can be the uplink data of the service. The source address of the second data is the same as the address of the first user equipment. In other words, the second data is data from the first user equipment. The user plane network element receives the second data from the third user equipment. Therefore, the user plane network element determines that the first user equipment is connected to the third user equipment, that is, the session associated with the address of the first user equipment is changed to the session of the third user equipment (the second session).

[0319] Optionally, the user plane network element stores the correspondence between the address of the first user equipment and the second session, based on the fact that the source address of the second data is the same as the address of the first user equipment.

[0320] For example, device x moves from UE1 (second user equipment) to UE2 (third user equipment) and sends an uplink data packet with source IP address #1 to UE2. UE2 forwards the uplink data packet to the UPF network element. The UPF network element receives the uplink data packet from UE2 and identifies the source IP address of the uplink data packet as IP address #1. The UPF network element determines the association between IP address #1 and UE2's PDU session and stores the mapping relationship between IP address #1 and UE2's PDU session.

[0321] The following describes two other methods for transmitting the first data, besides the user plane network element transmitting the first data through the second session.

[0322] In one possible implementation, the communication method may further include: the user plane network element determining multiple sessions associated with the address range of the group, including the address of the first data, based on the address range of the group, and transmitting the first data through at least two of the multiple sessions.

[0323] The address range of the group and multiple sessions can be found in the description in S602, and will not be repeated here.

[0324] It can be seen that the user plane network element transmits the first data through at least two of the multiple sessions associated with the address range of the group, which is similar to the way the first service data is transmitted in Scheme 1. That is, Scheme 1 and Scheme 2 can be used in combination. The user plane network element can change the session associated with the address of the first user equipment to the second session and transmit the first data in the second session, or it can transmit the first data through at least two sessions associated with the address range of the group.

[0325] Optionally, the user plane network element transmits the first data in at least two sessions within a preset time period. The preset time period can be a time period set according to actual conditions and needs, or it can be a time period configured locally by the user plane network element, such as 2s, 5s, etc.

[0326] For example, if the UPF network element determines that the IP address #1 of device x has switched from the session of UE1 to the session of UE2, that is, it senses that device x is moving, then it will transmit the downlink data packet in at least two PDU sessions among the multiple PDU sessions of the terminal devices in the group within 2 seconds.

[0327] This avoids data packet loss caused by frequent switching between terminal devices within the group when the first user equipment moves. For example, if the group includes UE1, UE2, and UE3, device x might switch from connecting to UE1 to UE2, and then switch back to UE3 within a short period (e.g., 2 seconds). When the UPF network element determines that the session corresponding to device x's IP address has been updated (switching from connecting to UE1 to UE2), it detects that device x is moving and transmits data packets across multiple PDU sessions associated with the group, thus preventing data packet loss.

[0328] In another possible implementation, the second user equipment is the master equipment; the communication method may further include: the user plane network element can transmit first data to the second user equipment through a first session, based on the second user equipment being the master equipment.

[0329] A master device can be a group-level device used to manage slave devices in the group to which the master device belongs, such as establishing connections with slave devices and exchanging signaling between them.

[0330] The master device has at least one of the following capabilities: assigning addresses, managing addresses, or a mapping between management addresses and slave devices. The master device can determine the connection status of each slave device in the group to the first user device in real time. For example, when each slave device in the group connects to the first user device, it reports the address of the first user device to the master device in real time. The master device may also have the ability to assign addresses to the first user device (such as device x mentioned above).

[0331] The distinction between master and slave devices among multiple terminal devices in a group can be determined through the interaction between the terminal devices. This application does not restrict how master and slave devices are negotiated.

[0332] Optionally, a connection is established between multiple terminal devices within the group, and the master and slave devices are negotiated.

[0333] For example, in a group containing UE1 and UE2, UE1 sends a message to UE2 carrying a master device indication, requesting that UE1 be designated as the master device. UE2 then sends a response message to UE1, which includes information agreeing to UE1 being designated as the master device.

[0334] For example, a group may contain UE1 and UE2. UE2 sends a message to UE1, carrying UE1's identifier and master device indication, requesting that UE1 be designated as the master device. UE1 sends a response message to UE2, which includes information agreeing to UE1 being the master device. Of course, other negotiation methods are possible, or the network side may designate the master and slave devices; this is not limited here.

[0335] Optionally, the subscription data of the second user equipment includes a master device indication. During the session establishment process of the second user equipment, the session management network element obtains the subscription data of the second user equipment and sends the master device indication to the user plane network element. Thus, the user plane network element can obtain information that the second user equipment is the master device.

[0336] Optionally, the third user equipment is a slave device. The user plane network element transmits the first data through the first session, which is also the session of the second user equipment. Since the second user equipment is the master device, it can know that the third user equipment is connected to the first user equipment, and thus forwards the first data to the third user equipment. This ensures that the first user equipment can receive the first data, guaranteeing the reliability of its services.

[0337] The interaction between user plane network elements and terminal devices (second user equipment and third user equipment) within the group has been described above. The interaction between the second user equipment and the third user equipment is described below through S11-S13, which are optional steps.

[0338] S11, the third user equipment sends the second information to the second user equipment, and correspondingly, the second user equipment receives the second information from the third user equipment.

[0339] The second information indicates the address of the first user equipment that is connected to the third user equipment for communication. The second user equipment and the third user equipment are included in the same group. The second user equipment is the master device and the third user equipment is the slave device. The group can be referred to the description in S601-S602, which will not be repeated here.

[0340] In other words, when a slave device connects to the first user equipment, it sends the address of the first user equipment to the master device, so that the master device can obtain the connection status between the slave device and the first user equipment in the group. For example, the slave device UE2 in the group reports the IP address #1 of the x device connected to UE2 to the master device UE1 in real time.

[0341] Optionally, prior to S11, the communication method may further include: a second user equipment receiving a request message, the request message being used to request the allocation of an address for a first user equipment. The second user equipment then instructs the first user equipment, based on the request message, on an address to be allocated to the first user equipment from an address range within a group, the address allocated to the first user equipment including the address of the first user equipment.

[0342] It is understandable that, since the second user equipment is the primary equipment, it has the capability to allocate addresses to the first user equipment. Therefore, after receiving a request message requesting an address to be allocated to the first user equipment, the second user equipment allocates an address to the first user equipment from the address range of the group. The address allocated to the first user equipment can be any address within the address range of the group. Subsequently, the first user equipment uses the address allocated to it to send service data. In other words, the address allocated to the first user equipment can be the address of the first user equipment mentioned above, and the service data is the second data of the aforementioned service.

[0343] Optionally, the request message originates from either the first user equipment or the third user equipment. The second user equipment directly receives the request message from the first user equipment, which is used to request an address to be allocated to the first user equipment. Alternatively, the first user equipment sends a request message to the third user equipment. Upon receiving the request message, the third user equipment, since it is a slave device and does not have the capability to allocate an address to the first user equipment, forwards the request message to the second user equipment as if it were the master device.

[0344] For example, UE1 is the master device in the group, and UE2 is the slave device. UE2 does not assign an IP address to device x. Instead, it forwards the received DHCP message to UE1, which then assigns an IP address to device x. In this way, only the second user device, acting as the master device, assigns an address to the first user device, avoiding multiple terminal devices assigning different addresses to the first user device. This also prevents the first user device from using different addresses to send service data, thus avoiding disruption to the service continuity of the first user device.

[0345] S12, when the second user equipment receives the first data of the service from the user plane network element, the second user equipment sends the first data to the third user equipment according to the address of the first data being the same as the address of the first user equipment.

[0346] The address of the first data can be the destination address of the first data. Since the destination address of the first data is the same as the address of the first user equipment, the second user equipment can determine that the first data should be sent to the first user equipment. The second user equipment obtains from the second information that the device communicating with the first user equipment is the third user equipment. Therefore, the second user equipment sends the first data to the third user equipment, so that the third user equipment can forward the first data to the first user equipment.

[0347] S13, the third user equipment receives the first data of the service from the second user equipment and / or user plane network elements.

[0348] The third user equipment can directly receive the first data from the user plane network element, or the user plane network element can send the first data to the second user equipment as the master equipment based on the second user equipment, and the second user equipment can send the first data to the third user equipment based on the second information, so that the third user equipment can receive the first data from the second user equipment.

[0349] Optionally, the communication method may further include: a third user equipment sending first data to a first user equipment.

[0350] Optionally, the third user equipment sending the first data to the first user equipment may include: after the third user equipment receives the first data sent by the user plane network element and the first data sent by the second user equipment, performing deduplication processing on the first data and sending the first data to the first user equipment.

[0351] In other words, the third user equipment receives the same first data from the user plane network element and the second user equipment, such as two identical data packets. The first data is then deduplicated, for example, by discarding the duplicate data packet. Alternatively, deduplication can be omitted, and the third user equipment can send all the received first data back to the first user equipment.

[0352] Optionally, the communication method may further include: before the third user equipment sends the second information to the second user equipment, the communication method may further include: the third user equipment receiving a request message from the first user equipment, the request message being used to request an address to be allocated to the first user equipment; the third user equipment sending the request message to the second user equipment based on the second user equipment being the master device. Since the master device has the ability to allocate an address to the first user equipment, while the slave device does not have the ability to allocate an address to the first user equipment, the third user equipment sends the request message to the second user equipment, and the second user equipment allocates an address to the first user equipment.

[0353] It can be seen that Solution 1 is mainly for ensuring the service reliability of device x when terminal devices within a group have the same status and there is no distinction between master and slave devices. Solution 2 is mainly for ensuring the service reliability of device x when terminal devices within a group are distinguished as master and slave devices. Of course, Solution 2 can be used in combination with Solution 1, and Solution 1 can also be used in scenarios where terminal devices within a group are distinguished as master and slave devices, while Solution 2 can also be used in scenarios where terminal devices within a group are not distinguished as master and slave devices.

[0354] The overall flow of the communication method of Scheme 2 provided in the embodiments of this application has been illustrated above with reference to Figure 8. The specific flow of the communication method of Scheme 2 provided in the embodiments of this application in a specific scenario is described below with reference to Figure 9.

[0355] Figure 9 is a schematic flowchart of the communication method provided in this embodiment. This communication method is applicable to the above-mentioned communication system and specifically involves the interaction between UPF network elements (i.e., user plane network elements), UE1 (i.e., second user equipment), UE2 (i.e., third user equipment), x device (i.e., first user equipment), AMF / SMF network elements, and UDM network elements.

[0356] The UPF network element determines that the session associated with the IP address of device x is updated to the session of UE2, thus confirming the connection between device x and UE2. Therefore, when the UPF network element receives downlink data from the data network, since the service is associated with the address of device x (or the destination address of the downlink data is the IP address of device x), the UPF network element transmits the downlink data through UE2's session based on the session association between device x's IP address and UE2. This allows downlink data to be transmitted to the connected terminal device (UE2) and then to device x, while maintaining the address of device x, even when device x moves between different terminal devices in the group. This supports communication between device x and the data network, thereby maintaining the service reliability of device x.

[0357] Specifically, as shown in Figure 9, the flow of this communication method is as follows:

[0358] S900, UDM network element extends UE session subscription data.

[0359] Optionally, the session subscription data may include master device indication information.

[0360] S901, UE1 initiates the registration process to 5GC.

[0361] S902, UE1 sends a first session establishment request message to the SMF network element through the AMF network element.

[0362] S903, the SMF network element obtains the subscription data corresponding to PDU session #1 from the UDM network element.

[0363] Optionally, UE1 is the master device, and the subscription data corresponding to PDU session #1 contains master device indication information.

[0364] S904, the SMF network element sends a second session establishment request message to the UPF network element.

[0365] S905, UPF network element storage first correspondence.

[0366] S906, the UPF network element sends a second session establishment response message to the SMF network element.

[0367] S907, the SMF network element sends a PDU session #1 establishment success response message to the AMF network element.

[0368] S908, the AMF network element sends a PDU session #1 establishment success response message to UE1.

[0369] The specific procedures for S900-S908 can be referenced from S700 to S708, and will not be elaborated further. The UE2 registration procedure and session establishment procedure can be referenced from UE1, and will not be elaborated further.

[0370] The following is the process by which UE1 assigns an IP address to device x.

[0371] S909, the x device sends a DHCP request message to UE1 or UE2.

[0372] The DHCP request message can be found in the description in S708, and will not be repeated here.

[0373] S910, UE2 forwards DHCP messages to UE1.

[0374] S910 is an optional step. UE2 establishes a local connection with UE1, such as an L2 connection. If device x sends a DHCP request message to UE2, then UE2, based on UE1 being the master device, sends a DHCP request message to UE1. That is, the slave device UE2 does not assign an IP address to device x, but forwards the DHCP message to the master device UE1, which then assigns an IP address to device x.

[0375] S911, UE1 selects IP address #1.

[0376] UE1 selects an IP address from the IP address range of the group corresponding to PDU session #1, such as selecting IP address #1 to assign to device x.

[0377] S912, UE1 sends a DHCP response message to device x.

[0378] The DHCP response message includes IP address #1.

[0379] S913, UE1 sends a DHCP response message to UE2.

[0380] S914, UE2 sends a DHCP response message to device x.

[0381] S914 and S913 are optional steps. If S910 is executed, then S913 and S914 will be executed.

[0382] S915, UE2 sends IP information to UE1.

[0383] UE2 reports IP information to UE1 in real time. The IP information (IP report) may include the IP address #1 of the x device connected to UE2. When UE2 establishes a connection with the x device, UE2 reports the IP address #1 of the x device to UE1 based on UE1 being the master device.

[0384] S916, UE1 sends a response message containing IP information to UE2.

[0385] S917, UE1 sends a PMF request message to the UPF network element.

[0386] S917 is an optional step. The PMF request message contains the mapping between the session information of slave device UE2 and IP address #1. This is because master device UE1 can obtain the IP address information reported by slave device UE2 in real time from S914. The UPF network element stores the mapping between UE2's session information and IP address #1. UE2's session information can be UE2's session identifier, UE2's identifier, etc.

[0387] The execution order of S909-S914 and S915-S917 is not limited. That is, S909-S914 can be executed before or after S915-S917.

[0388] The following describes the service process after device x switches from connecting to UE1 to connecting to UE2.

[0389] S918, after the x device switches from connecting to UE1 to connecting to UE2, it sends an uplink data packet to UE2.

[0390] S919, UE2 sends uplink data packets to the UPF network element, and correspondingly, the UPF network element receives uplink data packets from UE2.

[0391] S920, the UPF identifies the source IP address of the uplink data packet as IP address #1, and stores the correspondence between IP address #1 and UE2's PDU session #2.

[0392] S921, the UPF network element sends uplink data packets to the data network.

[0393] The execution order of S920 and S921 is not limited; that is, S921 can be executed before or after S920.

[0394] S922, the data network sends downlink data packets to the UPF network element, and correspondingly, the UPF network element receives downlink data packets from the data network.

[0395] Downlink data packets can be downlink data packets sent by the data network in response to uplink data packets, and the destination IP address of the downlink data packets is IP address #1.

[0396] S923, the UPF network element transmits downlink data packets to UE2 through UE2's PDU session #2.

[0397] The UPF obtains the destination IP address of the downlink data packet, i.e., IP address #1. The UPF stores the mapping between IP address #1 and UE2's PDU session #2. Therefore, it determines the UE2's PDU session #2 corresponding to IP address #1.

[0398] S924, the UPF network element sends downlink data packets to UE1.

[0399] S925, UE1 sends downlink data packets to UE2.

[0400] S924 and S925 are optional steps. Based on the IP information reported by UE2, UE1 determines that IP address #1 is associated with UE2, and then forwards downlink data packets to UE2.

[0401] S926, when UE2 receives downlink data packets from the UPF network element and UE1, it performs deduplication processing on the downlink data packets.

[0402] S926 is an optional step; deduplication can be omitted, and all received downlink data packets can be sent to device x.

[0403] S927, the UPF network element transmits downlink data packets through multiple PDU sessions corresponding to the IP address range of the group.

[0404] S927 is an optional step, and the solution of S722 can be referenced. That is, this solution can be used in combination with the solutions of S700-S725.

[0405] When a UPF network element detects that device x is moving, such as when the UPF learns that IP address #1 has switched from a session of UE1 to a session of UE2, it will transmit downlink data packets in all PDU sessions of the group within a certain time period (based on the time period value configured locally by the UPF, such as 2s or 5s).

[0406] S928, UE2 sends downlink data packets to device x.

[0407] UE2 matches the corresponding x device based on IP address #1, as described in S723, and will not be repeated here. It should be noted that UE1 and UE2 store the mapping relationship between IP address #1 and x device (not shown in Figure 9).

[0408] In this way, the UPF network element determines that the session associated with the IP address of device x is updated to the session of UE2, that is, it determines that device x is connected to UE2. Therefore, when the UPF network element receives downlink data from the data network, since the service is associated with the address of device x, or in other words, the destination address of the downlink data is the IP address of device x, the UPF network element transmits the downlink data through the session of UE2 based on the session association between the IP address of device x. In this way, when device x moves between different terminal devices in the group, downlink data can be transmitted to the terminal device (i.e., UE2) connected to device x while keeping the address of device x unchanged, and then to device x, to support communication between device x and the data network, thereby maintaining the service reliability of device x.

[0409] The method provided by the embodiments of this application has been described in detail above with reference to Figures 6-9. The communication apparatus used to perform the communication method provided by the embodiments of this application is described in detail below with reference to Figures 10-11.

[0410] Figure 10 is a schematic diagram of the structure of a communication device provided in an embodiment of this application. Exemplarily, as shown in Figure 10, the communication device 1000 includes a transceiver module 1001 and a processing module 1002. For ease of explanation, Figure 10 only shows the main components of the communication device.

[0411] The transceiver module 1001 is used to perform the transceiver function of the method shown in Figure 6 above, and the processing module 1002 is used to perform other functions of the method shown in Figure 7 above besides the transceiver function.

[0412] Optionally, the transceiver module 1001 may include a transmitting module (not shown in FIG10) and a receiving module (not shown in FIG10). The transmitting module is used to implement the transmitting function of the communication device 1000, and the receiving module is used to implement the receiving function of the communication device 1000.

[0413] Optionally, the communication device 1000 may further include a storage module (not shown in FIG10) that stores programs or instructions. When the processing module 1002 executes the program or instructions, the communication device 1000 can perform the functions of the terminal or network device in the method shown in FIG6 above.

[0414] It is understood that the communication device 1000 may be a terminal or network device, or a chip (system) or other component or assembly that can be set in the terminal or network device, or a device that includes the terminal or network device. This application does not limit it in this respect.

[0415] Furthermore, the technical effects of the communication device 1000 can be referred to the technical effects of the communication method shown in Figure 6, and will not be repeated here.

[0416] Figure 11 is a second schematic diagram of the structure of the communication device provided in an embodiment of this application. Exemplarily, the communication device can be a terminal, or a chip (system) or other component or assembly that can be disposed in the terminal. As shown in Figure 11, the communication device 1100 may include a processor 1101. Optionally, the communication device 1100 may also include a memory 1102 and / or a transceiver 1103. The processor 1101 is coupled to the memory 1102 and / or the transceiver 1103, for example, by means of a communication bus, an internal chip interface, or other communication lines. Optionally, the memory 1102 may be integrated with the processor 1101.

[0417] The following is a detailed description of each component of the communication device 1100 with reference to Figure 11:

[0418] The processor 1101 is the control center of the communication device 1100. It can be a single processor or a collective term for multiple processing elements. For example, the processor 1101 can be one or more central processing units (CPUs), application-specific integrated circuits (ASICs), or one or more integrated circuits configured to implement the embodiments of this application, such as one or more digital signal processors (DSPs), or one or more field-programmable gate arrays (FPGAs).

[0419] Optionally, the processor 1101 can perform various functions of the communication device 1100 by running or executing software programs stored in the memory 1102 and calling data stored in the memory 1102, such as performing the communication method shown in FIG7 above.

[0420] In a specific implementation, as one embodiment, processor 1101 may include one or more CPUs, such as CPU0 and CPU1 shown in FIG11.

[0421] In a specific implementation, as one embodiment, the communication device 1100 may also include multiple processors, such as processors 1101 and 1104 shown in FIG. 11. Each of these processors may be a single-core processor (single-CPU) or a multi-core processor (multi-CPU). Here, a processor may refer to one or more devices, circuits, and / or processing cores used to process data (e.g., computer program instructions).

[0422] The memory 1102 is used to store the software program that executes the solution of this application, and is controlled by the processor 1101 to execute it. The specific implementation method can be referred to the above method embodiment, and will not be repeated here.

[0423] Optionally, the memory 1102 may be a read-only memory (ROM) or other type of static storage device capable of storing static information and instructions, random access memory (RAM) or other type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited thereto. The memory 1102 may be integrated with the processor 1101 or may exist independently and be coupled to the processor 1101 through the interface circuit of the communication device 1100 (not shown in FIG. 11). This application embodiment does not specifically limit this.

[0424] Transceiver 1103 is used for communication with other communication devices. For example, if communication device 1100 is a terminal, transceiver 1103 can be used to communicate with a network device or with another terminal device. As another example, if communication device 1100 is a network device, transceiver 1103 can be used to communicate with a terminal or with another network device.

[0425] Optionally, transceiver 1103 may include a receiver and a transmitter (not shown separately in Figure 11). The receiver is used to implement the receiving function, and the transmitter is used to implement the transmitting function.

[0426] Optionally, the transceiver 1103 can be integrated with the processor 1101 or exist independently and be coupled to the processor 1101 through the interface circuit of the communication device 1100 (not shown in FIG11). This application embodiment does not specifically limit this.

[0427] It is understood that the structure of the communication device 1100 shown in Figure 11 does not constitute a limitation on the communication device. Actual communication devices may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0428] Furthermore, the technical effects of the communication device 1100 can be referred to the technical effects of the method described in the above method embodiments, and will not be repeated here.

[0429] It should be understood that the processor in the embodiments of this application can be a central processing unit (CPU), or it can be other general-purpose processors, DSPs, ASICs, FPGAs, or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0430] It should also be understood that the memory in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Non-volatile memory can be ROM, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), EEPROM, or flash memory. Volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM).

[0431] The above embodiments can be implemented, in whole or in part, by software, hardware (such as circuits), firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive.

[0432] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. Additionally, the character " / " in this article generally indicates an "or" relationship between the preceding and following related objects, but it can also represent an "and / or" relationship. Please refer to the context for a more accurate understanding.

[0433] In this application, "at least one" means one or more, and "more than one" means 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 multiple items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0434] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes 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.

[0435] 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.

[0436] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0437] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of 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.

[0438] 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.

[0439] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0440] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes all the various possible memories described above.

Claims

1. A communication method, characterized in that, include: The user plane network element receives the first service data from the data network; If the destination address of the first service data belongs to the address range associated with multiple sessions, the user plane network element transmits the first service data to at least two terminal devices through at least two of the multiple sessions. The at least two terminal devices are in a group, which includes multiple terminal devices capable of accessing the first network. The multiple sessions are sessions established by the user plane network element for a second device. The second device accesses the first network through the terminal devices. The address range is the address range used by the service data of the multiple terminal devices in the group.

2. The method according to claim 1, characterized in that, Before the user plane network element receives the first service data from the data network, the method further includes: The user plane network element receives a first message from the session management network element, the first message including indication information for indicating that the address range corresponds to multiple sessions; The user plane network element saves the correspondence between the address range and the multiple sessions according to the instruction information, and the correspondence is used to determine the multiple sessions.

3. The method according to claim 2, characterized in that, The indication information includes information about the multiple sessions and / or the address range.

4. The method according to claim 2 or 3, characterized in that, If the destination address of the first service data belongs to an address range associated with multiple sessions, then the user plane network element transmits the first service data to at least two terminal devices through at least two of the multiple sessions, including: If the destination address of the first service data belongs to the address range, the user plane network element determines the multiple sessions corresponding to the address range according to the correspondence; The user plane network element transmits the first service data to the at least two terminal devices through at least two of the multiple sessions.

5. The method according to any one of claims 1 to 4, characterized in that, The user plane network element transmits the first service data to at least two terminal devices through at least two of the plurality of sessions, including: The user plane network element replicates the first service data and transmits the first service data to the at least two terminal devices through each of the plurality of sessions.

6. A communication method, characterized in that, include: The first device receives second service data from the second device; If the address range of the group includes the address of the second service data, the first device sends the second service data to the user plane network element through the session corresponding to the group; the group includes multiple devices with the ability to access the first network, the multiple devices include the first device, and the second device accesses the first network through the first device.

7. The method according to claim 6, characterized in that, The address is the source address; the method further includes: The first device receives first service data from the user plane network element; The first device determines the second device corresponding to the destination address of the second service data based on the correspondence between the source address of the second service data and the second device, wherein the source address of the second service data is the same as the destination address of the first service data; The first device sends the first service data to the second device.

8. The method according to claim 7, characterized in that, Before the first device receives the first service data from the user plane network element, the method further includes: The first device stores the correspondence between the source address of the second service data and the second device.

9. The method according to any one of claims 6 to 8, characterized in that, Before the first device receives the second service data from the second device, the method further includes: The first device receives a second message from the session management network element, the second message indicating that the session was successfully established, and the second message includes the address range of the group corresponding to the session; The first device stores the correspondence between the address range of the session and the address range of the group according to the second message. The correspondence between the address range of the session and the address range of the group is used to determine the session corresponding to the group.

10. The method according to any one of claims 6 to 9, characterized in that, The method further includes: When the first device establishes a connection with the second device, the first device obtains the address assigned to the second device from the session management network element; the address range of the group includes the address assigned to the second device; The first device sends an address assigned to the second device; the address assigned to the second device includes the address of the second service data.

11. A communication method, characterized in that, include: The user plane network element determines that the address of the first user equipment is updated from being associated with the first session to being associated with the second session. The first session is the session of the second user equipment, the second session is the session of the third user equipment, the second user equipment and the third user equipment are included in the same group, the user equipment in the group has the ability to access the first network, and the first user equipment accesses the first network through the user equipment in the group; When the user plane network element receives the first data from the data network, the user plane network element associates the first data with the second session based on the address of the first user equipment, and transmits the first data to the third user equipment through the second session; The destination address of the first data is the same as the address of the first user equipment.

12. The method according to claim 11, characterized in that, The method further includes: The user plane network element receives first information sent from the second user equipment and / or the third user equipment, wherein the first information indicates the second session information and the address of the first user equipment; The user plane network element determines that the address of the first user equipment is updated from being associated with the first session to being associated with the second session, including: The user plane network element determines, based on the first information, that the address of the first user equipment is updated from being associated with the first session to being associated with the second session.

13. The method according to claim 11, characterized in that, The method further includes: The user plane network element receives the second data of the service from the third user equipment; The user plane network element obtains the source address of the second data; The user plane network element determines that the address of the first user equipment is updated from being associated with the first session to being associated with the second session, including: The user plane network element determines that the address of the first user equipment is updated from being associated with the first session to being associated with the second session, based on the fact that the source address of the second data is the same as the address of the first user equipment.

14. The method according to claim 11, characterized in that, After the user plane network element determines that the address of the first user equipment has been updated from being associated with the first session to being associated with the second session, the method further includes: The user plane network element determines multiple sessions associated with the address range of the group, including the address of the first data, based on the address range of the group; the multiple sessions are sessions established by the user plane network element for terminal devices in the group, and the address range is the address range used by the service data of the terminal devices in the group; The user plane network element transmits the first data through at least two of the plurality of sessions.

15. The method according to any one of claims 11 to 14, characterized in that, The second user equipment is the master equipment; the method further includes: The user plane network element transmits the first data to the second user equipment through the first session based on the second user equipment being the master device.

16. A communication method, characterized in that, include: The second user equipment receives second information from the third user equipment, the second information indicating the address of the first user equipment that is communicatively connected to the third user equipment, the second user equipment and the third user equipment are included in the same group, the second user equipment is the master device and the third user equipment is the slave device, the user equipment in the group has the ability to access the first network, and the first user equipment accesses the first network through the user equipment in the group. When the second user equipment receives first data from a user plane network element, the second user equipment sends the first data to the third user equipment based on the fact that the address of the first data is the same as the address of the first user equipment.

17. The method according to claim 16, characterized in that, Before the second user equipment receives the second information from the third user equipment, the method further includes: The second user equipment receives a request message, which is used to request an address to be allocated to the first user equipment; The second user equipment sends an address allocated to the first user equipment from the address range of the group according to the request message, wherein the address allocated to the first user equipment includes the address of the first user equipment.

18. The method according to claim 17, characterized in that, The request message originates from either the first user equipment or the third user equipment.

19. The method according to any one of claims 16 to 18, characterized in that, The method further includes: The second user equipment sends first information to the user plane network element, the first information indicating the session information of the third user equipment and the address of the first user equipment; the first information is used to determine that the first address is updated from being associated with the first session to being associated with the second session, the first session being the session of the second user equipment, and the second session being the session of the third user equipment.

20. The method according to any one of claims 1 to 19, characterized in that, The session is a Protocol Data Unit (PDU) session.

21. A communication method, characterized in that, include: The third user equipment sends second information to the second user equipment, the second information indicating the address of the first user equipment that has established a connection with the third user equipment. The second user equipment and the third user equipment are included in the same group. The second user equipment is the master equipment. The user equipment in the group has the ability to access the first network. The first user equipment accesses the first network through the user equipment in the group. The third user equipment receives first data from the second user equipment and / or user plane network elements, wherein the destination address of the first data is the same as the address of the first user equipment.

22. The method according to claim 21, characterized in that, The method further includes: The third user equipment sends the first data to the first user equipment.

23. The method according to claim 22, characterized in that, The third user equipment sends the first data to the first user equipment, including: When the third user equipment receives the first data sent by the user plane network element and the first data sent by the second user equipment, it performs deduplication processing on the first data; The third user equipment sends the first data to the first user equipment.

24. The method according to any one of claims 21 to 23, characterized in that, Before the third user equipment sends the second information to the second user equipment, the method further includes: The third user equipment receives a request message from the first user equipment, the request message being used to request that an address be allocated to the first user equipment; The third user equipment sends the request message to the second user equipment, where the second user equipment is the master equipment.

25. A communication device, characterized in that, The apparatus includes: a module for performing the method as described in any one of claims 1-10, or a module for performing the method as described in any one of claims 11-24.

26. A communication device, characterized in that, The communication device includes a processor and a memory; the memory is used to store computer instructions, which, when executed by the processor, cause the method as described in any one of claims 1-10 to be performed, or cause the method as described in any one of claims 11-24 to be performed.

27. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a computer program or instructions that, when executed on a computer, cause the computer to perform the method as claimed in any one of claims 1-10, or cause the computer to perform the method as claimed in any one of claims 11-24.

28. A computer program product, characterized in that, The computer program product includes a computer program or instructions that, when executed on a computer, cause the method as described in any one of claims 1-10 to be performed, or cause the method as described in any one of claims 11-24 to be performed.

29. A chip, characterized in that, The device includes a processor connected to a memory for storing a computer program, the processor for executing the computer program stored in the memory to cause the method as described in any one of claims 1-10 to be performed, or to cause the method as described in any one of claims 11-24 to be performed.

Images