Communication method and device

Abstract

The invention relates to the technical field of communication, in particular to a communication method and device, which can reduce communication delay. The method comprises: a first communication device (such as an SMF network element) receiving location information of a first device; and sending the information of the first UPF network element, the first UPF network element being determined according to the location information of the first device and the location information of the at least one UPF network element, the first UPF network element belonging to the at least one UPF network element, and the location information of the first UPF network element comprising a cell identifier of a cell associated with the first UPF network element and / or a node identifier of an associated access network node.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a communication method and apparatus. Background Technology

[0002] Currently, the 3rd Generation Partnership Project (3GPP) topology enhancement task group is researching network architectures based on wireless access and backhaul (WAB) nodes and femto nodes for coverage enhancement. The WAB-based architecture can be applied to scenarios such as vehicle-mounted relay (VMR), where WAB nodes can be deployed on vehicles, airplanes, or ships to provide wireless coverage for terminal devices within the vehicle, overcoming the problem of poor wireless signal strength in vehicles. The femto-based architecture can be used for coverage enhancement in indoor scenarios; femto nodes can be home base stations or new radio (NR) cells.

[0003] Furthermore, NR already supports local services, meaning it allows the deployment of user plane function (UPF) network elements providing data services on the radio access network (RAN) side, such as within or near the base station to which the terminal device is connected. However, current UPF network element selection is typically based on the tracking area (TA) where the terminal device is located. In scenarios where WAB nodes or femto nodes provide coverage enhancement, multiple UPF network elements may exist within a single TA, and there are usually UPF network elements associated with that TA on the core network (CN) side as well. Selecting different UPF network elements may introduce different communication latency to the terminal device; therefore, reducing communication latency is an urgent problem to be solved. Summary of the Invention

[0004] This application provides a communication method and apparatus that can reduce communication latency.

[0005] In a first aspect, embodiments of this application provide a communication method, which can be executed by a first communication device, wherein the first communication device can be a session management function (SMF) network element or a network repository function (NRF) network element. The method includes: receiving location information of a first device; and sending information of a first UPF network element, wherein the first UPF network element is determined based on the location information of the first device and the location information of at least one UPF network element, wherein the first UPF network element belongs to at least one UPF network element, and the location information of the first UPF network element includes the cell identifier of the cell associated with the first UPF network element and / or the node identifier of the associated access network node.

[0006] In the above communication method, the first device can be a terminal device or a mobile terminal in a relay node (such as a mobile terminal (MT) in a WAB node).

[0007] The above communication method enables SMF network elements to select local UPF network elements that are closer to the first device after receiving a session request from the first device, based on the location information of the first device and the detailed UPF network element location, including the cell identifier of the associated cell and / or the node identifier of the associated access network node, to provide services for the session, which helps to reduce the communication latency of the first device.

[0008] In one possible design, the first UPF network element is a local UPF network element, which may include at least one of the following: a UPF network element co-located with the first device; a UPF network element co-located with the serving access network node of the first device; a UPF network element deployed near the first device; or a UPF network element deployed near the serving access network node of the first device.

[0009] In this embodiment, the local UPF network element is a UPF network element co-located (or collocated) with the access network node (such as a gNB, WAB node, femto node, or femto gateway (GW)). It may include UPF network elements located alongside the access network node, and / or UPF network elements deployed near the access network node (e.g., UPF network elements whose deployment location is less than or equal to a set distance threshold from the access network node). This design allows the SMF network element to preferentially select the local UPF network element closest to the first device to provide services for the session requested by the first device, thus reducing the communication latency of the first device.

[0010] In one possible design, the method further includes receiving location information of the first UPF network element. Optionally, the location information of the first UPF network element may also include a tracking area identifier of the tracking area associated with the first UPF network element.

[0011] The above design enables local UPF network elements to report more detailed location information, including the cell identifier of the associated cell and / or the node identifier of the associated access network node, to the first communication device after deployment. This allows the first communication device to obtain more detailed location information of the local UPF network elements and more accurately select the UPF network elements that are closer to the first device.

[0012] Secondly, embodiments of this application provide a communication method that can be executed by an SMF network element. The method includes: receiving a session request, the session request being used to request the establishment of a session for transmitting Xn traffic; and establishing a session, wherein the session is provided by a second UPF network element, the second UPF network element being a local UPF network element.

[0013] In this embodiment, the local UPF network element is a UPF network element co-located (or collocated) with an access network node (such as a gNB, WAB node, femto node, or femto GW). For example, the local UPF network element may include one or more of the following: a UPF network element co-located with the second device sending the session request; a UPF network element co-located with the serving access network node of the second device; a UPF network element deployed near the second device sending the session request; or a UPF network element deployed near the serving access network node of the second device. The second device may be a mobile terminal (such as a WAB-MT) in a relay node (such as a WAB node), and Xn traffic may refer to signaling plane data and / or user plane data transmitted through the Xn interface.

[0014] Using the above communication method, when a request is made to establish a session for transmitting Xn traffic, the SMF network element can select a local UPF network element to provide services for the session for transmitting Xn traffic, avoiding Xn traffic from bypassing the UPF network element on the core network side, which helps to reduce communication latency.

[0015] In one possible design, the session request includes first indication information, which is used to indicate the selection of a local UPF network element to provide services for the session.

[0016] With the above design, when sending a session request, the second device can carry the first indication information in the session request to indicate the selection of a local UPF network element to provide services for the session, so that the SMF network element selects a local UPF network element for the session, avoiding Xn traffic from bypassing the UPF network element on the core network side.

[0017] In one possible design, before establishing a session, the method further includes: determining that the data network access identifier (DNAI) corresponding to the session request belongs to a first DNAI set, wherein the first DNAI set includes one or more DNAIs, and the one or more DNAIs are used to indicate the location information of the local UPF network element that can provide Xn traffic services.

[0018] Through the above design, by configuring a set of DNAIs that indicate the location information of local UPF network elements that can provide Xn traffic services, the SMF network element can be instructed to select a local UPF network element to provide services for the sessions corresponding to the DNAIs in the DNAI set, thus avoiding Xn traffic from bypassing the UPF network elements on the core network side.

[0019] In one possible design, the method further includes receiving a first DNAI set from policy control function (PCF) network elements or operations, administration and maintenance (OAM) network elements, etc.

[0020] The above design enables PCF network elements or OAM network elements to configure the first DNAI set for SMF network elements, and flexibly adjusts the strategy for SMF network elements to select UPF network elements.

[0021] Thirdly, embodiments of this application provide a communication method that can be executed by a relay node or a serving access network node of the relay node. The method includes: determining a first channel, wherein the UPF network element associated with the first channel is a local UPF network element; and sending Xn traffic from a first access network node through the first channel, wherein the first access network node is a first relay node, and the first relay node further includes a first mobile terminal.

[0022] In this embodiment, the local UPF network element is a UPF network element co-located (or collocated) with an access network node (such as a gNB, WAB node, femto node, or femto GW). For example, the local UPF network element may include one or more of the following: a UPF network element co-located with a first relay node, a UPF network element co-located with the serving access network node of the first relay node, a UPF network element deployed near the first relay node, or a UPF network element deployed near the serving access network node of the first relay node. The first channel can be a session or a tunnel between the access network node and the UPF network element.

[0023] The above communication method allows relay nodes or their service access network nodes to select the first channel of the corresponding local UPF network element to transmit Xn traffic, which avoids Xn traffic from detouring through the UPF network element on the core network side and helps reduce communication latency.

[0024] In one possible design, the first channel is the first session. Determining the first channel includes: sending a session establishment request, which is used to request the establishment of the first session, and the first session is used to provide backhaul for the first relay node; receiving a session establishment response, which includes second indication information, which indicates that the UPF network element providing services for the first session is a local UPF network element.

[0025] The above design allows SMF network elements to indicate whether the UPF network element serving the session is a local UPF network element when establishing a session. This is beneficial for relay nodes to select sessions served by local UPF network elements for backhauling Xn traffic.

[0026] In one possible design, the first channel is a first tunnel, which is a tunnel established between the serving access network node of the first relay node and the local UPF network element. Determining the first channel includes: obtaining the network address of at least one local UPF network element; and determining that the uplink network address of the first tunnel belongs to the network address of at least one local UPF network element.

[0027] The above design enables relay nodes to select tunnels with uplink network addresses matching the local UPF network element's network address after identifying Xn traffic. This avoids Xn traffic from bypassing the UPF network element on the core network side, which helps reduce communication latency.

[0028] Fourthly, embodiments of this application provide a communication method that can be executed by a UPF network element. The method includes: sending location information of the UPF network element, the location information including the cell identifier of the cell associated with the UPF network element and / or the node identifier of the associated access network node.

[0029] In one possible design, the location information of the UPF network element also includes the tracking area identifier of the tracking area associated with the UPF network element.

[0030] In one possible design, the UPF network element is a local UPF network element.

[0031] Fifthly, embodiments of this application provide a communication method that can be executed by a second device. The method includes: sending a session request, the session request including first indication information, the first indication information being used to indicate the selection of a local UPF network element to provide services for the session, the session request being used to request the establishment of a session for transmitting Xn traffic; receiving the established session, wherein the session is provided by a second UPF network element, the second UPF network element being a local UPF network element, wherein the local UPF network element includes at least one of the following: a UPF network element co-located with the second device that sent the session request, or a UPF network element co-located with the service access network node of the second device.

[0032] The second device can be a mobile terminal (such as WAB-MT) in a relay node (such as a WAB node), and Xn traffic can refer to signaling plane data and / or user plane data transmitted through the Xn interface.

[0033] Sixthly, embodiments of this application provide a communication method that can be executed by an SMF network element. The method includes: receiving a session establishment request, the session establishment request being used to request the establishment of a first session, the first session being used to provide backhaul for a first relay node; and sending a session establishment response, the session establishment response including second indication information, the second indication information indicating that the UPF network element providing services for the first session is a local UPF network element.

[0034] In a seventh aspect, embodiments of this application provide a communication device that has the function of implementing the method of any one of the first to sixth aspects described above, including units, modules, or means for implementing the above methods. The function can be implemented by hardware or by hardware executing corresponding software. The hardware or software includes one or more modules (or units) corresponding to the above functions, such as an interface unit and a processing unit.

[0035] In one possible design, the device can be a chip or an integrated circuit.

[0036] In one possible design, the device includes a memory and a processor, the memory for storing instructions executed by the processor, and when the instructions are executed by the processor, the device can perform the methods of any one of the first to sixth aspects described above.

[0037] Eighthly, embodiments of this application provide a communication device including an interface circuit and a processor, the processor and the interface circuit being coupled to each other. The processor implements the methods of any one of the first to sixth aspects described above through logic circuits or execution instructions. The interface circuit is used to receive signals from other communication devices outside the communication device and transmit them to the processor, or to send signals from the processor to other communication devices outside the communication device. It is understood that the interface circuit can be a transceiver, a transceiver terminal, or an input / output interface.

[0038] Optionally, the communication device may also include a memory for storing instructions executed by the processor, or storing input data required by the processor to execute instructions, or storing data generated after the processor executes instructions. The memory may be a physically independent unit, or it may be coupled to the processor, or the processor may include the memory (i.e., the processor and the memory are integrated together).

[0039] In one possible implementation, the communication device is a chip.

[0040] Ninthly, embodiments of this application provide a communication system, the communication system including a first communication device and a UPF network element, wherein the first communication device can execute the method described in the first aspect, and the UPF network element can execute the method described in the fourth aspect.

[0041] In a tenth aspect, embodiments of this application provide a communication system, which includes an SMF network element and a second device, wherein the SMF network element can execute the method described in the second aspect, and the second device can execute the method described in the fifth aspect.

[0042] Eleventhly, embodiments of this application provide a communication system, the communication system including a relay node or a serving access network node of a relay node and an SMF network element, wherein the relay node or the serving access network node of a relay node can perform the method described in the third aspect above, and the SMF network element can perform the method described in the sixth aspect above.

[0043] In a twelfth aspect, embodiments of this application provide a computer-readable storage medium storing a computer program or instructions that, when executed by a processor, can implement the methods of any one of the first to sixth aspects described above.

[0044] In a thirteenth aspect, embodiments of this application also provide a computer program product, including a computer program or instructions, which, when executed by a processor, can implement the methods of any one of the first to sixth aspects described above.

[0045] In a fourteenth aspect, embodiments of this application also provide a chip system including a processor and an interface. The processor is used to call and execute instructions from the interface. When the processor executes the instructions, it can implement the methods of any one of the first to sixth aspects described above.

[0046] The technical effects that can be achieved by aspects four through fourteen above are the same as those that can be achieved by aspects one through three above, and will not be repeated here. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the architecture of the communication system provided in the embodiments of this application;

[0048] Figure 2 A schematic diagram of the open RAN architecture provided in the embodiments of this application;

[0049] Figure 3 A schematic diagram of a WAB network provided in an embodiment of this application;

[0050] Figure 4 This is a schematic diagram of a network architecture based on femto nodes provided in an embodiment of this application;

[0051] Figure 5 This is a schematic diagram of UPF network element deployment provided in an embodiment of this application;

[0052] Figure 6 , Figure 7 This is a schematic diagram of a UPF network element selection scenario provided in an embodiment of this application;

[0053] Figure 8 , Figure 11 , Figure 14 This is a schematic diagram of a communication method provided in an embodiment of this application;

[0054] Figure 9 , Figure 10 This is a schematic diagram of UPF network element selection provided in an embodiment of this application;

[0055] Figure 12 , Figure 13 , Figure 15 , Figure 16 This is a schematic diagram of the Xn traffic transmission process provided in an embodiment of this application;

[0056] Figure 17 , Figure 18 This is a schematic diagram of the structure of the communication device provided in the embodiments of this application. Detailed Implementation

[0057] This application provides a communication method and apparatus. The method and apparatus are based on the same inventive concept. Since the principles by which the method and apparatus solve problems are similar, their implementations can be mutually referenced, and repeated details will not be repeated.

[0058] Figure 1 A schematic diagram of a possible, non-limiting communication system is shown. (For example...) Figure 1 As shown, the communication system 10 includes a radio access network (RAN) 100 and a core network (CN) 200. RAN 100 includes at least one RAN node (e.g., ...). Figure 1 110a and 110b (collectively referred to as RAN node 110) and at least one terminal device (such as Figure 1 120a-120j in RAN 100 are collectively referred to as terminal equipment 120. RAN 100 may also include other RAN nodes, such as wireless relay equipment and / or wireless backhaul equipment. Figure 1 (Not shown in the image). Terminal device 120 is connected to RAN node 110 wirelessly. RAN node 110 is connected to core network 200 wirelessly or via wired connection. The core network equipment in core network 200 and RAN node 110 in RAN 100 can be different physical devices, or they can be the same physical device integrating core network logical functions and radio access network logical functions.

[0059] RAN 100 can be a cellular system related to the 3rd Generation Partnership Project (3GPP), such as 4G, 5G mobile communication systems, or future-oriented evolution systems (such as 6G mobile communication systems). RAN 100 can also be an open RAN (O-RAN or ORAN) or a cloud radio access network (CRAN). RAN 100 can also be a communication system that integrates two or more of the above systems.

[0060] Understandable, Figure 1 This application only illustrates one possible communication system that can be applied to an embodiment of the present application. In other possible scenarios, the communication system may also include other devices.

[0061] RAN node 110, sometimes also referred to as access network equipment, RAN entity, access network node, network equipment, etc., constitutes part of the communication system and is used to help terminal equipment achieve wireless access. Multiple RAN nodes 110 in communication system 10 can be of the same type or different types. In some scenarios, the roles of RAN node 110 and terminal equipment 120 are relative, for example, Figure 1 Network element 120i can be a helicopter or a drone, and it can be configured as a mobile base station. For terminal devices 120j that access RAN 100 through network element 120i, network element 120i is a base station; however, for base station 110a, network element 120i is a terminal device. RAN node 110 and terminal device 120 are sometimes referred to as communication devices, for example... Figure 1 Network elements 110a and 110b can be understood as communication devices with base station functions, while network elements 120a-120j can be understood as communication devices with terminal equipment functions.

[0062] In one possible scenario, a RAN node can be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next-generation NodeB (gNB), or a next-generation base station in a 6th-generation (6G) mobile communication system, or a base station in a future mobile communication system, etc. A RAN node can also be a macro base station (such as...) Figure 1 110a), micro base stations (such as femto nodes) or indoor stations (such as Figure 1 The RAN node can be a relay node (such as a WAB node) or donor node, or a radio controller in a CRAN scenario. Optionally, the RAN node can also be a server, wearable device, vehicle, or in-vehicle equipment. For example, the access network equipment in vehicle-to-everything (V2X) technology can be a roadside unit (RSU). All or part of the functions of the RAN node in this application can also be implemented through software functions running on hardware, or through virtualization functions instantiated on a platform (such as a cloud platform). The RAN node in this application can also be a logical node, logical module, or software that can implement all or part of the functions of the RAN node.

[0063] In another possible scenario, multiple RAN nodes collaborate to assist terminal devices in achieving wireless access, with different RAN nodes each implementing a portion of the base station's functions. For example, RAN nodes can be central units (CUs), distributed units (DUs), CU-control plane (CPs), CU-user plane (UPs), or radio units (RUs), etc. CUs and DUs can be set up separately or included in the same network element, such as a baseband unit (BBU). RUs 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).

[0064] 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.

[0065] Reference Figure 2 The diagram shows an open RAN architecture. RAN node ( Figure 2 Taking a gNB as an example, the RAN node can include a RAN intelligent controller (RIC), gNB-CU, and gNB-DU. The RIC stands for O-RAN Intelligent Controller, which collects network information and performs necessary optimization tasks. It can communicate with gNB-CU and gNB-DU via the E2 interface. The gNB-CU represents a gNB-CU that supports O-RAN functions and can communicate with the RIC via the E2 interface and with the gNB-DU via the F1 interface. The gNB-DU represents a gNB-DU that supports O-RAN functions and can communicate with the RIC via the E2 interface, with the gNB-CU via the F1 interface, and with terminal equipment (…). Figure 2Taking user equipment (UE) as an example, communication occurs through the Uu interface. Additionally, it can be understood that the RAN node can also serve WAB nodes, femto nodes, or base stations serving WAB nodes. The base station serving the WAB node can also be called the WAB node's serving base station or host base station (donor-gNB, or simply donor). Figure 2 gNB-CU can also be replaced by donor-CU, WAB-CU or femto-CU, and gNB-DU can also be replaced by donor-DU, WAB-DU and femto-DU.

[0066] It should be noted that the above gNB-CU represents the CU in gNB, gNB-DU represents the DU in gNB, and similarly, donor-CU represents the CU in donor, WAB-CU represents the CU in WAB node, and femto-CU represents the CU in femto node. Similar descriptions have the same meaning in the following descriptions of this application and will not be explained separately.

[0067] Terminal devices can also be called terminals, user interfaces (UEs), mobile stations, mobile terminals, etc. Terminal devices can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), the Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, smart cities, etc. Terminal devices can be mobile phones, tablets, computers with wireless transceiver capabilities, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, etc. The embodiments of this application do not limit the device form of the terminal device. It is understood that for extended reality (XR) scenarios, the terminal device can be a smartphone, a head-mounted display (HMD), or smart glasses (such as virtual reality (VR) glasses, augmented reality (AR) glasses, etc.). For cloud gaming scenarios, the terminal device can be a smartphone or tablet.

[0068] The CN can include network elements such as network repository function (NRF), policy control function (PCF), access and mobility management function (AMF), session management function (SMF), user plane function (UPF), and service communication proxy (SCP).

[0069] AMF network elements: These are core network elements, primarily responsible for signaling processing, such as access control, mobility management, attach and detach functions, and gateway selection.

[0070] SMF network elements are primarily responsible for user plane network element selection, user plane network element redirection, Internet Protocol (IP) address allocation, bearer establishment, modification and release, and quality of service (QoS) control.

[0071] UPF network elements are primarily responsible for forwarding and receiving user data in terminal devices. They can receive user data from the data network and transmit it to the terminal device through the access network node; UPF network elements can also receive user data from the terminal device through the access network node and forward it to the data network.

[0072] PCF network element: It mainly supports providing a unified policy framework to control network behavior, provides policy rules to the control layer network functions, and is also responsible for obtaining user subscription information related to the policy.

[0073] NRF network elements: Their main functions include service discovery, maintaining the NF text of available network function (NF) instances and the services they support.

[0074] In addition, operation, administration and maintenance (OAM) network elements can be set up in the communication system. OAM network elements are mainly responsible for the management and maintenance of devices (or network elements) in the network, and support operations such as configuration, fault detection, fault isolation and error recovery of devices (or network elements) in the network.

[0075] It is understood that the aforementioned network element or function can be a network component in a hardware device, a software function running on dedicated hardware, or a virtualized function instantiated on a platform (e.g., a cloud platform). Optionally, the aforementioned network element or function can be implemented by one device, multiple devices working together, or a functional module within a single device; this application embodiment does not specifically limit this.

[0076] To facilitate understanding by those skilled in the art, some terms used in this application are explained below.

[0077] 1) WAB.

[0078] The 3GPP topology enhancement project is researching a new architecture for Web Application Base (WAB), primarily for VMR (Virtual Mobile Radio) scenarios. WAB nodes can be deployed on vehicles, airplanes, or ships to provide wireless coverage for terminal devices within these vehicles, overcoming the problem of poor wireless signal strength. WAB nodes can wirelessly backhaul to macro base stations (also known as host base stations), transmitting traffic from terminal devices connected to the WAB node back to the macro base station.

[0079] The WAB architecture is a layer 3 relay network, meaning that WAB nodes have full base station functionality. Figure 3 This is a schematic diagram of a WAB network provided in an embodiment of this application. The Uu interface is the interface between the terminal device (e.g., UE) and the access network node (e.g., gNB); the Xn interface is the interface between the access network node (e.g., gNB) and the access network node (e.g., the host gNB (donor-gNB)); the N2 interface is the interface between the access network node (e.g., gNB) and the AMF network element; the N3 interface is the interface between the access network node (e.g., gNB) and the UPF network element; and the N6 interface is the interface between the UPF network element and the data network. Additionally... Figure 3 The UE_UPF network element and UE_AMF network element can be understood as the UPF network element and AMF network element in the core network registered by the UE, or the UPF network element and AMF network element serving the UE; the mobile terminal (MT)_UPF network element and MT_AMF network element can be understood as the UPF network element and AMF network element in the core network registered by the MT, or the UPF network element and AMF network element serving the MT.

[0080] A WAB node includes gNB functionality (which can also be CU+DU functionality, as the gNB can have a CU and DU separate architecture) and mobile terminal (MT) functionality. That is, a WAB node comprises a gNB part and an MT part. The gNB part of the WAB node can be referred to as the WAB node's gNB, the WAB node's gNB function, or WAB-gNB, while the MT part of the WAB node can be referred to as the WAB node's MT, the WAB node's MT function, or WAB-MT. The WAB-MT accesses the network by connecting to the host gNB (which can be understood as the gNB serving the WAB-MT) to provide Protocol Data Unit (PDU) sessions for data backhaul from the WAB-gNB. The UE accesses the WAB-gNB via the Uu interface. The WAB-MT then encapsulates the UE's control plane or user plane data within the MT's PDU session. This data is transmitted through the MT's Uu interface, via the host gNB, and ultimately to the MT_UPF network element. The MT_UPF network element then removes the header information from the MT-related data packets, exposing the UE-related header information, and routes the data packets to the UE's core network (e.g., the UE_AMF network element or the UE_UPF network element) based on the destination IP address. Logically, a non-access stratum (NAS) connection is established between the UE and the UE_AMF network element for transmitting control plane data; a PDU session is established between the UE and the UE_UPF network element for transmitting data plane data. Both types of UE data are transmitted to the UE's core network within the MT's PDU session. The above example illustrates how a UE communicates with its core network within a WAB network architecture. Interface-level data transmission between the WAB-gNB and the UE's core network (such as the UE_AMF network element) is similar, requiring transmission to the MT_UPF network element via the MT's PDU session, and then routing to the UE_AMF network element. Logically, an N2 connection (also known as an NG connection) is established between the WAB-gNB and the UE_AMF network element, and an N3 tunnel is established between the WAB-gNB and the UE_UPF network element.

[0081] For a WAB-gNB, both the host gNB and its surrounding fixed gNBs can be considered its neighboring stations. A WAB-gNB can establish Xn connections with its neighboring stations, enabling mobility management of the UE. The implementation of Xn connections is similar to that of the N2 interface described above, and can be transmitted through the WAB-MT's PDU session. For example, Xn traffic sent by a WAB-gNB to the host gNB / other gNBs can first be transmitted to the MT_UPF network element via the WAB-MT's PDU session. Then, the MT_UPF network element decrypts the packet header and routes it to the corresponding neighboring station (i.e., the host gNB / other gNB) based on the destination IP address. Xn traffic sent by neighboring stations to the WAB-gNB operates in the same way, but in the opposite direction. Logically, thus, an Xn connection exists between the WAB-gNB and its neighboring stations.

[0082] This application uses a WAB node as a relay node as an example to illustrate the scheme, but the relay node is not limited to the WAB node, and can also be other nodes or network elements with relay functions.

[0083] 2) femto.

[0084] Another research direction in topology enhancement is network architecture based on femto nodes. Femto nodes are used for coverage enhancement in indoor scenarios and can include NR cells. In some implementations, DUs can also serve as femto nodes. Figure 4 This diagram illustrates a network architecture based on femto nodes, as provided in this application embodiment. Femto nodes can be directly connected to the 5G core network, or they can first connect to a femto gateway (GW) and then communicate with the 5G core network through the femto GW. In an architecture with a deployed femto GW, the femto GW acts as a proxy node between the femto node and the 5G core network. That is, the femto GW presents itself as a gNB to the 5G core network, but as the 5G core network to the femto node. The femto node and the core network it serves are not visible to each other. Optionally, the femto node network architecture may also include an Xn GW, used to forward Xn traffic between the femto node and neighboring sites (including other femto nodes and nearby fixed gNBs).

[0085] 3) Local service.

[0086] UE user plane data needs to be obtained through a PDU session with the core network. The UE can send a PDU session establishment request to the core network. This request can be carried in a NAS message and passed from the AMF (Advanced Management Function) element of the core network to the SMF (Supply Management Function) element. The SMF element then selects the UPF (Universal Power Filter) element to provide data transmission services for the PDU session based on the network slice associated with the requested PDU session, the data network name (DNN), the UE location information (such as the NR cell global identifier (NGCI) and tracking area identity (TAI) of the UE's serving cell), and the location information of available UPF elements (such as the TAI of the UPF element). (See reference...) Figure 5 The UPF network element deployment diagram shown illustrates that, without considering the deployment of local services, the UPF network element is located within the core network. Figure 5 In PDU session #1), SMF network elements can obtain the location information of available UPFs in the following four ways: 1) OAM network element configuration; 2) UPF network elements send their own location information to SMF network elements through the N4 interface; 3) The information registered by UPF network elements to NRF network elements contains their own location information, which SMF network elements can directly obtain from NRF network elements; 4) The information registered by UPF network elements to NRF network elements contains their own location information, which SMF network elements can obtain from NRF network elements through SCP.

[0087] NR already supports local services, meaning it supports deploying UPF network elements providing data transmission services on the RAN side, such as within the base station connected to the UE or near it. When a UE requests local services, the base station (such as gNB, WAB-gNB, donor, or femto node) indicates the UE's location information to the AMF network element. This UE location information and the PDU session establishment request are then sent by the AMF network element to the SMF network element. The SMF network element determines the corresponding DNAI(s) based on the UE's location information and the application mapping associated with the PDU session, and then selects a local UPF network element to provide data transmission services according to existing UPF network element selection principles. Figure 5 (China PDU Session #2).

[0088] 4) Tracking area (TA).

[0089] Location TA is a concept established for the location management of mobile devices. It can refer to an area consisting of a set of cells that can be used to manage and control the location and mobility of mobile devices (such as UEs).

[0090] 5) Sending / receiving information. 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, "access network node sending information" can be understood as an access network node sending information to another device (such as a terminal device), or it can be understood as logical module 1 in the access network node sending information to logical module 2 in the access network node.

[0091] 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, "access network node receiving information" can be understood as an access network node receiving information from another device (such as a terminal device), or it can be understood as logical module 1 in the access network node receiving information from logical module 2 in the access network node.

[0092] In this application, the phrase "sending information to... (e.g., a terminal device)" or the related illustrations in the accompanying drawings can be understood as the destination of the information being the terminal device. This can include sending information directly or indirectly to the terminal device. Similarly, "receiving information from... (e.g., a terminal device)," "receiving information from... (e.g., a terminal device)," or "receiving information sent (e.g., by a terminal device)," or the related illustrations in the accompanying drawings, can be understood as the source of the information being the terminal device. This can include receiving information directly or indirectly from the terminal device. 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.

[0093] like Figure 6 As shown, in scenarios where WAB nodes or femto nodes provide coverage enhancement, local UPF network elements and RAN nodes are collocated, and multiple UPF network elements may exist within a single TA. Figure 6 Taking TA#1 as an example (containing local UPF network element #1 and local UPF network element #2), since the location of the UPF network element is at the TA granularity, if the distance to the terminal device is selected ( Figure 6 (Taking UE as an example) If a UPF network element is located far away and serves the terminal device, it may result in a longer communication delay. Therefore, how to select UPF network elements in order to bring better communication delay to the terminal device is a question worth considering.

[0094] In addition, such as Figure 7 As shown, for the implementation of WAB-gNB Xn connection, if the WAB-gNB Xn traffic is routed to the neighboring station through the UPF network element deployed on the CN side ( Figure 7(Taking other gNBs as an example) the middle neighbor station may cause a long communication delay. Therefore, how to ensure that the Xn traffic of WAB-gNB can be forwarded to the neighbor station through the local UPF route in order to reduce the communication delay is also a problem worth considering.

[0095] Based on this, embodiments of this application provide a communication method and apparatus to accurately select local UPF network elements to provide local services to terminal devices and reduce communication latency. The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0096] Furthermore, it should be understood that the ordinal numbers such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects, and are not used to limit the size, content, order, timing, priority, or importance of the multiple objects. For example, "first instruction information" and "second instruction information" do not indicate a difference in priority or importance between the two instruction information.

[0097] In this application embodiment, the number of nouns, unless otherwise specified, refers to "singular nouns or plural nouns," that is, "one or more." "At least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship. For example, A / B means: A or B. "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 means: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.

[0098] Figure 8 A schematic diagram of a communication method provided in an embodiment of this application is shown. The method includes:

[0099] S801: The second communication device sends the location information of the first device to the first communication device, and correspondingly, the first communication device receives the location information of the first device.

[0100] In the embodiments of this application, the first device may be a terminal device such as a UE, or a mobile terminal (such as WAB-MT) in a relay node.

[0101] The first communication device can be a session management function (AMF) network element, and the second communication device can be a first device or an access and mobility management function (AMM) network element connected to the first device; or the first communication device can be a network storage function (NRF) network element, and the second communication device can be a session management function (AMF) network element. The access and mobility management function (AMF) network element can be the aforementioned AMF network element, or a network element in a future communication system such as a 6G system that has the aforementioned AMF network element function; the network storage function (NRF) network element can be the aforementioned NRF network element, or a network element in a future communication system such as a 6G system that has the aforementioned NRF network element function; similarly, the session management function (SMF) network element can be the aforementioned SMF network element, or a network element in a future communication system such as a 6G system that has the aforementioned SMF network element function. For ease of explanation, this embodiment uses the example of an access and mobility management function (AMF) network element, a network storage function (NRF) network element, and a session management function (AMF) network element.

[0102] After accessing the communication network, the first device can send a session establishment request (such as a PDU session establishment request) to the SMF network element to request the establishment of a session (such as a PDU session). The session establishment request sent by the first device is transmitted to the SMF network element via the AMF network element. After receiving the session request from the first device, the SMF network element can select the UPF network element to provide services for the session based on the location information of the first device. The location information of the first device can be carried in the session request or provided to the SMF network element by the AMF network element. For example, after receiving the session establishment request from the first device, the AMF network element sends the location information of the first device and the session establishment request to the SMF network element.

[0103] S802: The first communication device sends information about the first UPF network element, and correspondingly, the third communication device receives information about the first UPF network element. The first UPF network element is determined based on the location information of the first device and the location information of at least one UPF network element. The first UPF network element belongs to at least one UPF network element, and the location information of the first UPF network element includes the cell identifier of the cell associated with the first UPF network element and / or the node identifier of the associated access network node.

[0104] In the embodiments of this application, the third communication device may be the same as or different from the second communication device. For example: when the first communication device is an SMF network element and the second communication device is a first device, the third communication device may be different from the second communication device and may be a serving access network node of the first device; when the first communication device is an SMF network element and the second communication device is an AMF network element connected to the first device, the third communication device may be the same as the second communication device and may be an AMF network element connected to the first device, or it may be different from the second communication device and may be a serving access network node of the first device; when the first communication device is an NRF network element and the second communication device is an SMF network element, the third communication device may be the same as the second communication device and may be an SMF network element.

[0105] In one possible implementation, after the local UPF network element (which can also be called a distributed UPF network element) is deployed, it can send registration information, including the location information of the local UPF network element, to the SMF network element. When the first device sends a session request to obtain local services (e.g., the requested application / service (such as video services, data backhaul services, etc. identified by a specific network slice or DNN) is an application / service supported by the local UPF network element), the SMF network element can determine the UPF network element (i.e., the first UPF network element) to provide services for the session based on the location information of the first device and the location information of at least one UPF network element. The local UPF network element is a UPF network element that is co-located (or collocated) with the access network node (such as gNB, WAB node, femto node, or femto GW, etc.), and may include UPF network elements set up together with the access network node and / or UPF network elements deployed near the access network node.

[0106] As an example: Reference Figure 9The diagram illustrating UPF network element selection shows that after deployment, the local UPF network element can send registration information, including its location information, to the SMF network element. This location information may include the cell identifier (e.g., NCGI, or cell identity document ID) of the associated cell and / or the node identifier (e.g., gNB ID, WAB node ID, femto node ID, or femto GW ID) of the associated access network node, as well as the TAI of the associated TA. Alternatively, the OAM network element can send the local UPF network element's location information to the SMF network element after deployment to configure the location information for the SMF network element. Upon receiving a session request for local service, the SMF network element can select a first UPF network element to provide service for the session based on the location information of the first device (e.g., the cell identifier of the serving cell and / or the TAI of the TA to which the serving cell belongs) and the location information of at least one deployed UPF network element. After the SMF network element selects the first UPF network element, the SMF network element can communicate with the first UPF network element in the control plane, and can also provide the information of the first UPF network element (such as IP address) to the service access network node of the first device. The service access network node of the first device can determine the uplink destination IP address of the user plane transmission based on the information of the first UPF network element (such as IP address).

[0107] As an example: An SMF network element receives location information from UPF network elements #1, #2, #3, and #4. UPF network elements #1, #2, and #3 are local UPF network elements, while UPF network element #4 is a UPF network element deployed on the core network side. The location information for UPF network element #1 includes WAB-node ID #1 and TAI #1; the location information for UPF network element #2 includes gNB ID #2 and TAI #1; the location information for UPF network element #3 includes gNB ID #3 and TAI #2; and the location information for UPF network element #4 includes TAI #1. The location information for the first device includes cell ID #1 and TAI #1. After receiving a session request from the first device, the SMF network element can determine that UPF network elements #1, #2, and #4 can provide services for the session based on the location information at the TA granularity (TAI #1) of the first device. Furthermore, the SMF network element can select UPF network element #1 to provide services for the session based on the location information (cell ID#1) at the first device cell / node granularity, where cell ID#1 identifies cell #1 as the cell of WAB-node #1 identified by WAB-node ID#1, and the location information of UPF network element #1 includes the node identifier WAB-node ID#1 of WAB-node #1.

[0108] In some implementations, the applications of different UPF network elements may differ. SMF network elements can also select the UPF network element (i.e., the first UPF network element) to provide services for the session based on the application requested in the session establishment request.

[0109] As an example: taking the first device as the UE as an example, refer to... Figure 6As shown, two femto nodes (i.e., two RAN nodes) are deployed within TA#1. Each femto node deploys a local UPF network element. After the UE accesses femto node #1, it requests local services (such as the applications supported by local UPF network element #1 and local UPF network element #2). The AMF network element sends the UE location information (TAI#1 and NCGI#1, and optionally, the identifier femto node ID#1 of femto node #1 (i.e., RAN node #1)) and the PDU session request associated with the local service (such as application A) to the SMF network element. Based on local services (such as application A), the UE's location information (TAI#1), and the location information (TAI#1) of available UPF network elements (such as UPF network elements supporting application A), the network element discovers that both local UPF network element #1 and local UPF network element #2 within TA#1 can meet the requirements for session services. Furthermore, the SMF network element can compare cell / node granularity and select the local UPF network element #1 deployed in NCGI#1 or femto node #1 to provide data transmission services for the UE based on the UE's cell / node granularity location information (NCGI#1 or femto node ID#1). For example, the UE can be replaced with a WAB-MT, and the UE's core network can be replaced with the WAB-MT's core network, thus enabling the selection of a local UPF network element to provide data transmission services for the WAB-MT's backhaul PDU sessions.

[0110] In another possible implementation, after the local UPF network element is deployed, it can send registration information, including the location information of the local UPF network element, to the NRF network element. When the first device sends a session request to obtain local services (e.g., the requested application / service (such as video service, data backhaul service, etc. identified by a specific network slice or DNN) is an application / service supported by the local UPF network element), the SMF network element can determine the UPF network element (i.e., the first UPF network element) that provides services for the session through the NRF network element.

[0111] As an example: Reference Figure 10As shown, after deployment, the local UPF network element can send its location information to the NRF network element. This location information may include the cell identifier (e.g., NCGI, or cell ID) of the associated cell and / or the node identifier (e.g., gNB ID, WAB node ID, femto node ID, or femto GW ID) of the associated access network node, and may also include the TAI of the associated TA. Alternatively, the OAM network element can send the local UPF network element's location information to the NRF network element after deployment to configure the SMF network element's location information. Upon receiving a session establishment request, the SMF network element can send a request message containing the location information of the first device to the NRF network element / SCP, requesting UPF information. The request message may also carry information about the application requested in the session establishment request. Then, the NRF network element / SCP determines the UPF network element (i.e., the first UPF network element) to provide services for the session based on the location information of the first device and the location information of at least one UPF network element, and replies to the SMF network element with response information including information of the first UPF network element (such as one or more of the information such as IP address or identification).

[0112] For the case where the UPF network element (i.e., the first UPF network element) is determined by the SMF network element to provide services for the session through the NRF network element, the following possible implementation methods are possible.

[0113] Implementation Method 1: The SMF network element can send a request message containing the location information of the first device to the NRF network element. This request message can also carry information about the application requested for the session establishment request. Based on the location information of the first device and the location information of at least one UPF network element, the NRF network element determines the local UPF network element (i.e., the first UPF network element) to provide services for the session and replies to the SMF network element with a response message including information about the first UPF network element (such as its IP address). The SMF network element can directly communicate with this first UPF network element in the control plane and can also provide the IP address of the first UPF network element to the first device's serving access network node as the uplink destination IP address for user plane transmission.

[0114] Implementation Method 2: The SMF network element can send a request message containing the location information of the first device to the NRF network element, requesting UPF information. The request message can also carry information about the application requested for the session establishment request. Based on the location information of the first device and the location information of at least one UPF network element, the NRF network element determines the local UPF network element (i.e., the first UPF network element) to provide services for the session and replies to the SMF network element with a response message including information about the first UPF network element (such as its IP address). The SMF network element can communicate with the first UPF network element via SCP for control plane communication, and can also provide the IP address of the first UPF network element to the first device's serving access network node as the uplink destination IP address for user plane transmission.

[0115] Implementation Method 3: The SMF network element can send a request message to the SCP, including the location information of the first device. This request message can also carry information about the application requested for the session establishment request. The SCP then forwards the request message to the NRF network element. Based on the location information of the first device and at least one UPF network element, the NRF network element determines the local UPF network element (i.e., the first UPF network element) to provide services for the session and replies to the SCP with a response including information about the first UPF network element (such as its IP address). The SCP then returns the information of the first UPF network element to the SMF network element. The SMF network element can communicate with this first UPF network element via the SCP in the control plane and can also provide the IP address of the first UPF network element to the first device's serving access network node as the uplink destination IP address for user plane transmission.

[0116] The implementation of NRF network element determining the first UPF network element can be referred to the implementation of SMF network element determining the first UPF network element, and will not be elaborated further.

[0117] The above method allows for the selection of local UPF network elements that are close to the first device (such as a UE or a mobile terminal in a relay node) to provide session services, which helps reduce the communication latency of the first device. For example, when the first device is a UE, UPF network elements co-located with the UE's serving access network node or deployed near the UE's serving access network node can be selected to provide session services, thereby reducing the UE's communication latency. When the UE is a WAB-MT, UPF network elements co-located with the WAB, deployed near the WAB, co-located with the WAB-MT's serving access network node, or deployed near the WAB-MT's serving access network node can be selected to provide session services, thereby reducing the WAB-MT's communication latency.

[0118] In some implementations, Xn traffic from relay nodes can also be routed to neighboring stations via local UPF network elements to reduce communication latency for Xn traffic. Xn traffic can refer to signaling plane data and / or user plane data transmitted through the Xn interface.

[0119] Figure 11 This is a schematic diagram of another communication method provided in an embodiment of this application. The method includes:

[0120] S1101: The second device sends a session request (such as a PDU session establishment request) to the SMF network element, and the SMF network element receives the session request accordingly. This session request is used to request the establishment of a session (such as a PDU session) for transmitting Xn traffic.

[0121] S1102: The SMF network element establishes a session. The session is provided by the second UPF network element, which is a local UPF network element.

[0122] In this embodiment, the second device may be a mobile terminal (such as WAB-MT) in a relay node (such as a WAB node). The local UPF network element is a UPF network element that is co-located (or collocated) with the access network node (such as a gNB, WAB node, etc.), including UPF network elements set up together with the access network node and / or UPF network elements deployed near the access network node.

[0123] In one possible implementation, the SMF network element can identify the purpose of the session or the corresponding service. For sessions used to transmit Xn traffic (e.g., the session request carries indication information for transmitting Xn traffic, or the session request contains network slice information or DNN information for Xn traffic, etc.), the SMF network element can, by default, select a local UPF network element to provide services for the requested session based on the location information of the second device (e.g., the NCGI of the serving cell and the TAI of the TA). Taking the second device as a mobile terminal in a relay node as an example, it can choose a UPF network element co-located with the relay node, or a UPF network element deployed near the relay node, or a UPF network element co-located with the serving access network node (e.g., the host gNB) of the mobile terminal in the relay node, or a UPF network element deployed near the serving access network node of the mobile terminal in the relay node to serve the session and provide data transmission services to the access network node in the relay node.

[0124] In another possible implementation, the second device may carry first indication information in the session request used to transmit Xn traffic. The first indication information is used to indicate the selection of a local UPF network element to provide services for the session. The SMF network element can select the local UPF network element to provide services for the session based on the first indication information. Xn traffic can be sent to the local UPF network element through the session established by the second device, and then routed to the neighboring station (i.e., the adjacent access network node) by the local UPF network element.

[0125] Reference Figure 12 As shown, taking the second device as WAB-MT, the session as a PDU session, and the session establishment request as a PDU session establishment request as an example, Figure 12 This is a schematic diagram of an Xn traffic transmission process provided in an embodiment of this application. The process includes:

[0126] S1201: The WAB-MT sends a PDU session establishment request to the SMF network element, and the SMF network element receives the PDU session establishment request accordingly. The PDU session establishment request is used to request the establishment of a PDU session for transmitting Xn traffic, and the PDU session establishment request carries first indication information for indicating the selection of a local UPF network element to provide services for the PDU session.

[0127] As an example: WAB-MT can send a PDU session establishment request to the WAB-MT core network via NAS messages, requesting the establishment of a PDU session for transmitting Xn traffic of WAB-gNB. The PDU session establishment request can carry first indication information to indicate the selection of the local UPF as the service provider for this PDU session. This PDU session establishment request message is sent from the AMF network element on the core network side to the SMF network element.

[0128] The first indication information can be direct indication information, such as a 1-bit indication field. When the 1-bit indication field is 1, it indicates that the local UPF network element is selected to provide services for the PDU session. When the 1-bit indication field is 0, it does not restrict whether the local UPF network element or the core network side UPF network element is selected to provide services for the PDU session.

[0129] The first indication information can also be indirect indication information, such as one or more of the following: UE route selection policy (URSP) rules for Xn traffic (which indicate that Xn traffic of WAB-gNB is regarded as WAB-MT application), network slicing information for Xn traffic, or DNN information for Xn traffic. When the SMF network element carries one or more of the above information (such as carrying DNN information for Xn traffic) in the PDU session request, it can determine and indicate the selection of the local UPF network element to provide services for the PDU session.

[0130] 1202: The SMF network element sends a PDU session establishment accept message to the WAB-MT, and the WAB-MT receives the PDU session establishment accept message accordingly.

[0131] Based on the first instruction information, the SMF network element can select a local UPF network element (i.e., the second UPF network element) close to the WAB-MT location for the requested PDU session, based on the WAB-MT's location information (TAI and / or NCGI of the serving cell of the WAB-MT). For example, it can select a UPF network element deployed on the WAB node or on the host gNB of the WAB node to provide service for the PDU session. It can also send the selected local UPF network element (i.e., the second UPF network element) information (such as its IP address) to the host gNB of the WAB-MT (i.e., the gNB serving the WAB-MT) via a PDU session resource establishment request message.

[0132] 1203: WAB-MT sends Xn traffic from WAB-gNB to the local UPF network element via PDU session.

[0133] After the PDU session for transmitting Xn traffic is established, the WAB-MT sends the Xn traffic from the WAB-gNB to the local UPF network element through the PDU session for transmitting Xn traffic, and then the local UPF network element routes it to the neighboring station. Figure 12 (Taking a neighboring site as an example, other gNBs can also be the host gNB of a WAB, etc.)

[0134] Additionally, due to the movement of WAB nodes, WAB-MT may undergo a handover, which may also cause changes to the local UPF network elements surrounding WAB-MT. In some implementations, the SMF network element of WAB-MT can continue to prioritize the selection of local UPF network elements for providing services for PDU sessions used to transmit Xn traffic, based on the previous context information of WAB-MT. If no suitable local UPF network element is found (such as a local UPF network element deployed within the TA where WAB-MT is located), then the SMF network element needs to select a UPF network element deployed in the core network to provide services for PDU sessions used to transmit Xn traffic.

[0135] In another possible implementation, a first DNAI set (DNSI(s)) can be added for Xn traffic. This first DNAI set includes one or more DNAIs, which can be used to indicate the location information of local UPF network elements capable of providing Xn traffic services. When the DNAI corresponding to a session request belongs to the first DNAI set, the SMF network element selects the local UPF network element to provide services for the session. This first DNAI set can be configured by PCF network elements or OAM network elements, for example, by the PCF network element or OAM network element sending a control policy (such as a policy and charging control (PCC) rule) to the SMF network element to configure the first DNAI set.

[0136] Reference Figure 13 As shown, taking the second device as WAB-MT, the session as PDU session, the session establishment request as PDU session establishment request, and the first DNAI set configured by the PCF network element as an example. Figure 13 This is a schematic diagram of an Xn traffic transmission process provided in an embodiment of this application. The process includes:

[0137] S1301: The PCF network element sends a control policy to the SMF network element, and the SMF network element receives the control policy accordingly. The control policy indicates the first DNAI set.

[0138] In one possible implementation, the PCF network element can determine one or more DNAIs that indicate the location information of local UPF network elements that can provide Xn traffic services, based on the location information of local UPF network elements deployed near the WAB node (such as the location information of local UPF network elements deployed within the TA where the WAB node is located, or the location information of local UPF network elements whose distance from the WAB node is less than a set distance threshold) and the rule that treats the Xn traffic of WAB-gNB as a local service (that is, treats the Xn traffic of WAB-gNB as an application of WAB-MT, which can be provided by the local UPF network element for data transmission services), and send a control policy to the SMF network element that can be used to indicate a first DNAI set including the one or more DNAIs.

[0139] S1302: The WAB-MT sends a PDU session request to the SMF network element, and the SMF network element receives the session establishment request accordingly. This PDU session establishment request is used to request the establishment of a PDU session for transmitting Xn traffic.

[0140] As an example: WAB-MT can send a PDU session establishment request to the WAB-MT core network via NAS messages, requesting the establishment of a PDU session for transmitting Xn traffic of WAB-gNB. This PDU session establishment request message is sent from the AMF network element on the core network side to the SMF network element.

[0141] 1303: The SMF network element sends a PDU session establishment accept message to the WAB-MT, and the WAB-MT receives the PDU session establishment accept message accordingly.

[0142] After receiving a PDU session establishment request, the SMF network element can determine the corresponding DNAI based on the application (Xn traffic) requested by the WAB-MT and the location of the WAB-MT. This DNAI belongs to the first DNAI set. The SMF network element can select a local UPF network element (i.e., the second UPF network element) to provide services for the session and establish a PDU session based on this DNAI (such as the location information of the local UPF network element that can provide Xn traffic services indicated by the DNAI). It can then send the information (such as the IP address) of the selected local UPF network element (i.e., the second UPF network element) to the host gNB of the WAB-MT via a PDU session resource establishment request message.

[0143] 1304: WAB-MT sends Xn traffic from WAB-gNB to the local UPF network element via PDU session.

[0144] After the PDU session for transmitting Xn traffic is established, the WAB-MT sends the Xn traffic from the WAB-gNB to the local UPF network element through the PDU session for transmitting Xn traffic, and then the local UPF network element routes it to the neighboring station. Figure 13 (Taking a neighboring site as an example, other gNBs can also be the host gNB of a WAB, etc.)

[0145] Additionally, due to the movement of WAB nodes, WAB-MT may undergo a handover, which may also cause changes to the local UPF network elements surrounding WAB-MT. In some implementations, the SMF network element of WAB-MT can continue to prioritize the selection of a local UPF network element for providing services for PDU sessions used to transmit Xn traffic, based on the previous context information of WAB-MT. If no suitable local UPF network element is found (such as a local UPF network element deployed within the TA where WAB-MT is located), then the SMF network element needs to select a UPF deployed in the core network to provide services for PDU sessions used to transmit Xn traffic.

[0146] Understandably, in Figures 11-13 In the communication method shown, when the SMF network element selects a local UPF network element to provide services for a session, the selection can be based on the location information at the TA granularity of the local UPF network element, or it can be based on more fine-grained location information of the local UPF network element. For example, using... Figure 8 The method shown selects local UPF network elements based on location information including the cell identifier of the associated cell and / or the node identifier of the associated access network node. Figures 11-13 In the communication method shown, there is no limitation on the selection of the local UPF network element mode for the SMF network element in the session.

[0147] In some implementations, the Xn traffic of the relay node can also be routed to neighboring stations by the mobile terminal in the relay node or the serving access network node of the relay node, so as to reduce the communication latency of the Xn traffic.

[0148] Figure 14 This is a schematic diagram of another communication method provided in an embodiment of this application. The method includes:

[0149] S1401: The fourth communication device determines the first channel. The UPF network element associated with the first channel is the local UPF network element.

[0150] In this embodiment, the fourth communication device can be the first mobile terminal (such as WAB-MT) in the first relay node or the serving access network node of the first relay node (such as the host gNB of WAB). The local UPF network element is a UPF network element co-located (or collocated) with the access network node (such as gNB, WAB node, etc.), including the UPF network element co-located with the first relay node, or the UPF network element co-located with the serving access network node of the first relay node.

[0151] S1402: The fourth communication device transmits Xn traffic from the first access network node through the first channel. The first access network node is a first relay node, which also includes the first mobile terminal.

[0152] In one possible implementation, the fourth communication device can be the first mobile terminal in the first relay node, the channel can be a session (such as a PDU session), the fourth communication device can establish one or more sessions, select the associated UPF network element as the local UPF network element session as the first session, and send Xn traffic through the first session.

[0153] For example: A first mobile terminal in a first relay node can send a session establishment request to an SMF network element to request the establishment of a session for providing backhaul to the first relay node, and receive a session establishment response from the SMF network element. If the session established by the SMF network element is serviced by a local UPF network element, the SMF network element can carry second indication information in the session establishment response indicating that the UPF network element providing service for the session is the local UPF network element. When sending Xn traffic, the first mobile terminal in the first relay node can choose to send Xn traffic to a session where the UPF network element providing service for the session is the local UPF network element.

[0154] Reference Figure 15 As shown, taking the fourth communication device as the first mobile terminal in the first relay node, the first relay node as WAB, the first mobile terminal in the first relay node as WAB-MT, the first access network node in the first relay node as WAB-gNB, and the session as a PDU session as an example. Figure 15 This is a schematic diagram of an Xn traffic transmission process provided in an embodiment of this application. The process includes:

[0155] S1501: The WAB-MT sends a PDU session establishment request to the SMF network element, and the SMF network element receives the PDU session establishment request accordingly. This PDU session establishment request is used to request the establishment of a PDU session for providing backhaul (BH).

[0156] S1502: The SMF network element sends a PDU session establishment accept message to the WAB-MT, and correspondingly, the WAB-MT receives the PDU session establishment accept message.

[0157] After receiving a PDU session establishment request, the SMF network element selects a UPF network element to establish the session. If the selected local UPF network element provides services for the PDU session, the SMF network element can carry a second indication information in the PDU session establishment acceptance message. The second indication information indicates that the UPF network element providing services for the PDU session is a local UPF network element. That is, it indicates that the WAB-MT provides local services for the PDU session, or it indicates that the UPF network element providing data transmission services for the PDU session is a local UPF network element.

[0158] S1503: WAB-MT received Xn traffic from WAB-gNB.

[0159] S1504: WAB-MT determines the first PDU session. The first PDU session is provided by the local UPF network element.

[0160] S1505: WAB-MT sends Xn traffic through the first PDU session.

[0161] After receiving Xn traffic from WAB-gNB, WAB-MT can select the first PDU session provided by the local UPF network element to transmit the Xn traffic, which can then be routed to neighboring stations (such as other gNBs) by the local UPF network element.

[0162] In some implementations, WAB-MT can also instruct SMF network elements that PDU sessions (such as the first PDU session) served by local UPF network elements are used to transmit Xn traffic. Thus, after a WAB node moves, the SMF network element of WAB-MT can continue to prioritize local UPF network elements for serving PDU sessions used to transmit Xn traffic based on the previous context information of WAB-MT. If no suitable local UPF network element is found (such as a local UPF network element deployed in the TA where WAB-MT is located), then the SMF network element needs to select a UPF network element deployed in the core network to serve PDU sessions used to transmit Xn traffic.

[0163] In one possible implementation, the fourth communication device can be the serving access network node of the first relay node, and the channel can be a tunnel (such as the N3 tunnel between the serving access network node of the first relay node and the UPF network element). The fourth communication device can select the associated UPF network element as the tunnel of the local UPF network element as the first tunnel, and send Xn traffic through the first tunnel.

[0164] For example, WAB-MT can establish one or more sessions, each session including a tunnel (such as an N3 tunnel) between the host gNB and a UPF network element. Different tunnels can correspond to different UPF network elements and different uplink network addresses (such as IP addresses). The serving access network node of the first relay node can obtain the network address of at least one local UPF network element. When sending Xn traffic, the serving access network node of the first relay node can select a tunnel whose uplink network address belongs to the network address of at least one local UPF network element to send Xn traffic.

[0165] Reference Figure 16 As shown, taking the serving access network node of the first relay node as the host gNB, the first relay node as WAB, the first mobile terminal in the first relay node as WAB-MT, and the first access network node in the first relay node as WAB-gNB as an example. Figure 16 This is a schematic diagram of an Xn traffic transmission process provided in an embodiment of this application. The process includes:

[0166] S1601: The host gNB obtains the network address of at least one local UPF network element.

[0167] When a local UPF network element is deployed near the WAB node, the host gNB can obtain the network address (e.g., IP address) of at least one local UPF network element deployed near the WAB node. Specifically, the host gNB can obtain the network address of at least one local UPF network element deployed near the WAB node from the OAM network element, RIC, or the local UPF network element. Alternatively, if the local UPF network element is deployed within the WAB node, the host gNB can obtain the network address of the local UPF network element from the WAB node. Furthermore, if the session established by WAB-MT is serviced by a local UPF network element, the SMF network element can also send the network address of the local UPF network element to the host gNB via the AMF network element.

[0168] S1602: WAB-MT sends Xn traffic from WAB-gNB to the host gNB.

[0169] For example: After receiving Xn traffic from WAB-gNB, WAB-MT can send it to the host gNB through the data radio bearer (DRB) associated with the WAB-MT's backhaul PDU session.

[0170] S1603: The host gNB confirms the first tunnel.

[0171] WAB-MT can establish one or more PDU sessions, where each PDU session includes a tunnel (such as an N3 tunnel) between the host gNB and the UPF network element. After the host gNB recognizes the Xn traffic of WAB-gNB, it can determine the tunnel whose uplink network address (such as an uplink IP address) is the network address of the local UPF network element based on the network address (such as an IP address) of at least one local UPF network element.

[0172] 1604: The host gNB sends Xn traffic through the first tunnel.

[0173] The Xn traffic of the WAB-gNB is transmitted to the local UPF network element through the first tunnel between the host gNB and the local UPF network element, and can be routed to neighboring stations (such as other gNBs) by the local UPF network element.

[0174] In some implementations, WAB-MT can also indicate to the SMF network element that the PDU session belonging to the tunnel with the uplink network address of the local UPF network element (such as the first tunnel) is used to transmit Xn traffic. Thus, after the WAB node moves, the SMF network element of WAB-MT can continue to prioritize the local UPF network element for providing services for the PDU session used to transmit Xn traffic based on the previous context information of WAB-MT. If no suitable local UPF network element is found (such as the local UPF network element deployed in the TA where WAB-MT is located), then the SMF network element needs to select the UPF deployed in the core network to provide services for the PDU session used to transmit Xn traffic.

[0175] In some implementations, to enable the SMF network element to select the local UPF network element to provide Xn traffic data transmission services for mobile terminals (taking WAB-MT as an example) in the relay node, the following methods can also be used:

[0176] Method A: The location information of local UPF network elements can be pre-configured to the WAB node through methods such as access network node broadcasting and factory pre-configuration. When the WAB-MT wants to join the network, it can select a cell with local UPF network elements to initiate access based on the location information of local UPF network elements and the cell location information broadcast. For example, if the pre-configured location information of local UPF network elements includes TAI#1 and / or NCGI#1, the WAB-MT will prioritize accessing the cell broadcasting TAI#1 and / or NCGI#1 when joining the network; or, the WAB's serving access network node can add indication information to the cell broadcast to indicate whether there is a local UPF network element in the cell, so that the WAB-MT will prioritize accessing the cell with local UPF network elements.

[0177] Method B: If the SMF network element of WAB-MT cannot select a local UPF network element to provide service for the session requested by WAB-MT, it can instruct the AMF network element to redirect the WAB-MT pair based on the location information of the available local UPF network elements, redirecting it to an access network node that has (or is nearby to) a local UPF network element. For example, the AMF network element can send the frequency point information contained in the access network node with the local UPF network element to the serving access network node of WAB-MT, so that the serving access network node of WAB-MT can instruct WAB-MT to reselect to a nearby cell with a local UPF network element.

[0178] Method C: Considering the switching of WAB-MT, the establishment / update message of the Xn interface can be supplemented with an indication of whether a local UPF network element is deployed. In this way, when the source access network node determines the target access network node, it can prioritize the access network node with a local UPF network element deployed as the target access network node based on the information exchanged by Xn.

[0179] It is understood that, in order to achieve the functions in the above embodiments, the first communication device, the second communication device, the third communication device, the fourth communication device, or the SMF network element, etc., include hardware structures and / or software modules corresponding to perform each function. Those skilled in the art should readily recognize that, based on the units and method steps of the various examples described in conjunction with the embodiments disclosed in this application, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application scenario and design constraints of the technical solution.

[0180] Figure 17 and Figure 18 The diagram illustrates the possible communication devices provided in the embodiments of this application. These communication devices can be used to implement the functions of the first communication device, second communication device, third communication device, fourth communication device, or SMF network element in the above method embodiments, and thus can also achieve the beneficial effects of the above method embodiments.

[0181] like Figure 17 As shown, the communication device 1700 includes a processing unit 1710 and an interface unit 1720. The processing unit 1710 can be a processor or a processing circuit, and the interface unit 1720 can be a transceiver unit, an input / output interface, or a transceiver, etc. The communication device 1700 can be used to implement the steps executed by the first communication device, the second communication device, the third communication device, the fourth communication device, or the SMF network element in the above embodiments.

[0182] When the communication device 1700 is used to implement the steps performed by the first communication device in the above embodiments:

[0183] Interface unit 1720 is used to receive the location information of the first device;

[0184] The processing unit 1710 is configured to determine the first UPF network element based on the location information of the first device and the location information of at least one UPF network element, wherein the first UPF network element belongs to at least one UPF network element, and the location information of the first UPF network element includes the cell identifier of the cell associated with the first UPF network element and / or the node identifier of the associated access network node.

[0185] Interface unit 1720 is also used to send information about the first user plane function (UPF) network element.

[0186] In one possible design, the interface unit 1720 is also used to receive the location information of the first UPF network element.

[0187] In one possible design, the location information of the first device includes the cell identifier of the serving cell of the first device and / or the tracking area identifier of the tracking area to which the serving cell belongs.

[0188] In one possible design, the location information of the first UPF network element also includes the tracking area identifier of the tracking area associated with the first UPF network element.

[0189] In one possible design, the first device is a terminal device or a mobile terminal in a relay node.

[0190] In one possible design, the first UPF network element is a local UPF network element, which includes at least one of the following: a UPF network element co-located with the first device; or a UPF network element co-located with the service access network node of the first device.

[0191] When the communication device 1700 is used to implement the steps performed by the SMF network element in the above embodiments:

[0192] Interface unit 1720 is used to receive session requests, which are used to request the establishment of a session for transmitting Xn traffic;

[0193] Processing unit 1710 is used to establish a session, wherein the session is provided by a second UPF network element, the second UPF network element being a local UPF network element, wherein the local UPF network element includes at least one of the following: a UPF network element co-located with the second device that sent the session request, or a UPF network element co-located with the service access network node of the second device.

[0194] In one possible design, the session request includes first indication information, which is used to indicate the selection of a local UPF network element to provide services for the session.

[0195] In one possible design, before establishing a session, the processing unit 1710 is further configured to determine that the DNAI corresponding to the session request belongs to a first DNAI set, wherein the first DNAI set includes one or more DNAIs, and the one or more DNAIs are used to indicate the location information of the local UPF network element that can provide Xn traffic services.

[0196] In one possible design, the interface unit 1720 is also used to receive the first DNAI set.

[0197] When the communication device 1700 is used to implement the steps performed by the fourth communication device in the above embodiments:

[0198] Processing unit 1710 is used to determine a first channel, wherein the UPF network element associated with the first channel is a local UPF network element, wherein the local UPF network element includes at least one of the following: a UPF network element co-located with the first relay node, or a UPF network element co-located with the serving access network node of the first relay node.

[0199] Interface unit 1720 is used to send Xn traffic from a first access network node through a first channel, wherein the first access network node is a first relay node, and the first relay node also includes a first mobile terminal.

[0200] In one possible design, the first channel is the first session. When the processing unit 1710 determines the first channel, it is specifically used to send a session establishment request through the interface unit 1720. The session establishment request is used to request the establishment of the first session, which is used to provide backhaul for the first relay node. The processing unit 1710 also receives a session establishment response, which includes second indication information. The second indication information indicates that the UPF network element providing services for the first session is a local UPF network element.

[0201] In one possible design, the first channel is the first tunnel, which is a tunnel established between the serving access network node of the first relay node and the local UPF network element. When the processing unit 1710 determines the first channel, it is specifically used to obtain the network address of at least one local UPF network element; and to determine that the uplink network address of the first tunnel belongs to the network address of at least one local UPF network element.

[0202] like Figure 18As shown, this application also provides a communication device 1800, including a processor 1810 and potentially a communication interface 1820. The processor 1810 and the communication interface 1820 are coupled to each other. It is understood that the communication interface 1820 can be a transceiver, input / output interface, input interface, output interface, interface circuit, etc. Optionally, the communication device 1800 may further include a memory 1830 for storing instructions executed by the processor 1810, or storing input data required by the processor 1810 to execute instructions, or storing data generated after the processor 1810 executes instructions. The memory 1830 can be a physically independent unit coupled to the processor 1810, or the processor 1810 and the memory 1830 can be integrated together.

[0203] When the communication device 1800 is used to implement the steps executed by the first communication device, second communication device, third communication device, fourth communication device, or SMF network element in the above embodiments, the processor 1810 can be used to implement the function of the processing unit 1710, and the communication interface 1820 can be used to implement the function of the interface unit 1720.

[0204] It is understood that the processor in the embodiments of this application can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), logic circuits, field-programmable gate arrays (FPGAs), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor can be a microprocessor or any conventional processor.

[0205] The method steps in the embodiments of this application can be implemented in hardware or by a processor executing software instructions. The software instructions can consist of corresponding software modules, which can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, portable hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Additionally, the ASIC can reside in a network device or terminal device. Alternatively, the processor and storage medium can exist as discrete components in the network device or terminal device.

[0206] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are performed entirely or partially. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user equipment, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions can be transferred from one network device, terminal, computer, server, or data center to another network device, terminal, computer, server, or data center via wired or wireless 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 integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a digital video optical disc; or it can be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both types of storage media.

[0207] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of different embodiments are consistent and can be referenced by each other. The technical features of different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0208] Additionally, it should be understood that in the embodiments of this application, the term "exemplary" is used to indicate that it is an example, illustration, or description. Any embodiment or design scheme described as "exemplary" in this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of the term "exemplary" is intended to present the concept in a concrete manner.

[0209] It is understood that the various numerical designations used in the embodiments of this application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application. The order of the process numbers described above does not imply the order of execution; the execution order of each process should be determined by its function and internal logic.

Claims

1. A communication method, characterized in that, include: Receive the location information of the first device; Send information about the first User Plane Function (UPF) network element, which is determined based on the location information of the first device and the location information of at least one UPF network element. The first UPF network element belongs to the at least one UPF network element, and the location information of the first UPF network element includes the cell identifier of the cell associated with the first UPF network element and / or the node identifier of the associated access network node.

2. The method as described in claim 1, characterized in that, The method further includes: Receive the location information from the first UPF network element.

3. The method as described in claim 1 or 2, characterized in that, The location information of the first device includes the cell identifier of the serving cell of the first device and / or the tracking area identifier of the tracking area to which the serving cell belongs.

4. The method as described in claim 3, characterized in that, The location information of the first UPF network element also includes the tracking area identifier of the tracking area associated with the first UPF network element.

5. The method according to any one of claims 1-4, characterized in that, The first device is a terminal device or a mobile terminal in a relay node.

6. The method according to any one of claims 1-5, characterized in that, The first UPF network element is a local UPF network element, and the local UPF network element includes at least one of the following: A UPF network element co-located with the first device; or, A UPF network element co-located with the service access network node of the first device.

7. A communication method, characterized in that, include: Receive a session request, which is used to request the establishment of a session for transmitting Xn traffic; The session is established, wherein the session is provided by a second user plane function UPF network element, the second UPF network element being a local UPF network element, wherein the local UPF network element includes at least one of the following: a UPF network element co-located with the second device that sent the session request, or a UPF network element co-located with the service access network node of the second device.

8. The method as described in claim 7, characterized in that, The session request includes first indication information, which is used to indicate the selection of a local UPF network element to provide services for the session.

9. The method as described in claim 7 or 8, characterized in that, Before establishing the session, the method further includes: The data network access identifier (DNAI) corresponding to the session request is determined to belong to a first DNAI set, wherein the first DNAI set includes one or more DNAIs, and the one or more DNAIs are used to indicate the location information of the local UPF network element that can provide Xn traffic services.

10. The method as described in claim 9, characterized in that, The method further includes: Receive the first DNAI set.

11. A communication method, characterized in that, include: A first channel is determined, wherein the user plane function UPF network element associated with the first channel is a local UPF network element, wherein the local UPF network element includes at least one of the following: a UPF network element co-located with the first relay node, or a UPF network element co-located with the service access network node of the first relay node. Xn traffic from a first access network node is sent through the first channel, wherein the first access network node is a first relay node, and the first relay node further includes a first mobile terminal.

12. The method as described in claim 11, characterized in that, The first channel is the first session, and determining the first channel includes: Send a session establishment request, the session establishment request being used to request the establishment of the first session, the first session being used to provide backhaul to the first relay node; A session establishment response is received, the session establishment response including second indication information, the second indication information indicating that the UPF network element providing services for the first session is a local UPF network element.

13. The method as described in claim 11, characterized in that, The first channel is a first tunnel, which is a tunnel established between the serving access network node of the first relay node and the local UPF network element. Determining the first channel includes: Obtain the network address of at least one local UPF network element; It is determined that the uplink network address of the first tunnel belongs to the network address of the at least one local UPF network element.

14. A communication device, characterized in that, It includes units for performing the method as described in any one of claims 1-6, or the method as described in any one of claims 7-10, or the method as described in any one of claims 11-13.

15. A communication device, characterized in that, The device includes a processor and an interface circuit. The interface circuit is used to receive signals from other communication devices besides the communication device and transmit them to the processor, or to send signals from the processor to other communication devices besides the communication device. The processor is used to implement the method as described in any one of claims 1-6, or the method as described in any one of claims 7-10, or the method as described in any one of claims 11-13 through logic circuits or execution instructions.

16. A computer program product, characterized in that, It includes a computer program or instructions that, when executed by a processor, cause the method of any one of claims 1-6, or the method of any one of claims 7-10, or the method of any one of claims 11-13 to be implemented.

17. A chip system, characterized in that, The chip system includes: A processor and an interface, the processor being configured to invoke and execute instructions from the interface, wherein, when the processor executes the instructions, it implements the method as described in any one of claims 1-6, or the method as described in any one of claims 7-10, or the method as described in any one of claims 11-13.

18. A computer-readable storage medium, characterized in that, The storage medium stores a computer program or instructions that, when executed by a processor, cause the method as described in any one of claims 1-6, or the method as described in any one of claims 7-10, or the method as described in any one of claims 11-13 to be implemented.

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