WO2026000213A1 - Data transmission method and apparatus, and device, chip and storage medium - Google Patents

Abstract

Provided in the embodiments of the present application is a data transmission method, which is applied to a first sub-terminal. The method comprises: sending first information to a head node, wherein the first information is used for requesting or indicating the switching of a transmission mode of first data to a target transmission mode, the first data is sent by a first sub-terminal and received by a second sub-terminal, the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal by means of the head node. On the basis of the method in the embodiments of the present application, first information can be used to request or indicate the switching of a transmission mode of first data to a first transmission mode or a second transmission mode, and in the first transmission mode, the first data can be forwarded (or routed) by a head node without needing to go through forwarding by a core network device. Therefore, by switching the transmission mode of the first data, whether the first data needs to be forwarded by the core network device can be flexibly controlled, thereby flexibly controlling a transmission delay of the first data.

Description

A data transmission method, apparatus, device, chip, and storage medium Technical Field

This application relates to the field of communication technology, specifically to a data transmission method, apparatus, device, chip, and storage medium.

Background Technology

Currently, the routing of local service data requires the participation of the core network. For example, for local service data from terminal #1 to terminal #2, the data transmission must pass through: terminal #1, base station (gNB), User Plane Function (UPF), base station (gNB), and terminal #2 in sequence. It is evident that the local service data sent by terminal #1 needs to be forwarded by the UPF, resulting in a relatively long data transmission delay.

Summary of the Invention

This application provides a data transmission method, apparatus, device, chip, and storage medium.

In a first aspect, embodiments of this application provide a data transmission method applied to a first sub-terminal. The method includes: sending first information to a head node, the first information being used to request or indicate switching the transmission mode of first data to a target transmission mode, the first data being sent by the first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

Secondly, embodiments of this application provide a data transmission method applied to a head node. The method includes: receiving first information from a first sub-terminal, the first information being used to request or indicate switching the transmission mode of first data to a target transmission mode, the first data being sent by the first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

Thirdly, embodiments of this application provide a data transmission method applied to a head node. The method includes: sending first information to a first sub-terminal, the first information being used to instruct switching the transmission mode of first data to a target transmission mode, the first data being sent by the first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

Fourthly, embodiments of this application provide a data transmission method applied to a first sub-terminal. The method includes: receiving first information from a head node, the first information indicating that the transmission mode of first data be switched to a target transmission mode, the first data being sent by the first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

Fifthly, embodiments of this application provide a data transmission method applied to a core network device. The method includes: sending first information to a head node, the first information being used to indicate switching the transmission mode of first data to a target transmission mode, the first data being sent by a first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In a sixth aspect, embodiments of this application provide a data transmission method applied to a head node. The method includes: receiving first information from a core network device, the first information being used to indicate switching the transmission mode of first data to a target transmission mode, the first data being sent by a first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In a seventh aspect, embodiments of this application provide a data transmission apparatus, the apparatus comprising: a first communication unit configured to send first information to a head node, the first information being used to request or indicate switching the transmission mode of first data to a target transmission mode, the first data being sent by the apparatus and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

Eighthly, embodiments of this application provide a data transmission apparatus, the apparatus comprising: a second communication unit configured to receive first information from a first sub-terminal, the first information being used to request or indicate switching the transmission mode of first data to a target transmission mode, the first data being sent by the first sub-terminal and received by the second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the apparatus.

Ninthly, embodiments of this application provide a data transmission apparatus, the apparatus comprising: a third communication unit configured to send first information to a first sub-terminal, the first information being used to instruct the switching of the transmission mode of first data to a target transmission mode, the first data being sent by the first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the apparatus.

In a tenth aspect, embodiments of this application provide a data transmission apparatus, the apparatus comprising: a fourth communication unit configured to receive first information from a head node, the first information being used to indicate switching the transmission mode of first data to a target transmission mode, the first data being sent by the apparatus and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

Eleventhly, embodiments of this application provide a data transmission device, the device comprising: a fifth communication unit configured to send first information to a head node, the first information being used to instruct the switching of the transmission mode of first data to a target transmission mode, the first data being sent by a first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In a twelfth aspect, embodiments of this application provide a data transmission apparatus, the apparatus comprising: a sixth communication unit configured to receive first information from a core network device, the first information being used to instruct switching the transmission mode of first data to a target transmission mode, the first data being sent by a first sub-terminal and received by a second sub-terminal; wherein the target transmission mode is a first transmission mode or a second transmission mode, and when the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the apparatus.

In a thirteenth aspect, embodiments of this application provide a communication device, comprising: a memory for storing a computer program; a processor connected to the memory for calling and running the computer program from the memory to implement the method described in any one of the first to sixth aspects; and a transceiver for receiving and sending information during the exchange of information with other devices.

In a fourteenth aspect, embodiments of this application provide a chip. The chip includes: a processor for retrieving and running a computer program from a memory, causing a device on which the chip is installed to perform the method described in any one of the first to sixth aspects; and a transceiver for receiving and sending information during the exchange of information with the device or the chip.

In a fifteenth aspect, embodiments of this application provide a computer-readable storage medium for storing a computer program that causes a computer to perform the method described in any one of the first to sixth aspects.

According to the method in the embodiments of this application, the transmission mode of the first data can be switched to a first transmission mode or a second transmission mode through a first information request or instruction. In the first transmission mode, the first data can be forwarded (or routed) by the head node without needing to be forwarded by the core network equipment. Therefore, by switching the transmission mode of the first data, it is possible to flexibly control whether the first data needs to be forwarded by the core network equipment, thereby flexibly controlling the transmission delay of the first data.

Attached Figure Description

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

Figure 1 is a schematic diagram of an application scenario of an embodiment of this application;

Figure 2 is a schematic diagram of a micro-domain terminal (sub-UE) communicating with a wide area network (macro network) via HP according to an embodiment of this application;

Figure 3 is a schematic diagram of the deployment of WAB technology provided in an embodiment of this application;

Figure 4 is a schematic diagram of an example of a 5G virtual network group provided in an embodiment of this application;

Figure 5 is a schematic diagram of several data forwarding methods of UPF provided in the embodiments of this application;

Figure 6 is an architecture diagram of LIPA or SIPTO provided in the embodiments of this application;

Figure 7 is a schematic flowchart of a data transmission method provided in an embodiment of this application;

Figure 8 is a schematic diagram of two data transmission methods provided in the embodiments of this application;

Figure 9 is a schematic flowchart of a data transmission method provided in an embodiment of this application;

Figure 10 is a schematic flowchart of a data transmission method provided in an embodiment of this application;

Figure 11 is a schematic diagram of a possible implementation flow of the data transmission method provided in an embodiment of this application;

Figure 12 is a schematic diagram of another possible implementation flow of the data transmission method provided in the embodiments of this application;

Figure 13 is a schematic diagram of another possible implementation flow of the data transmission method provided in the embodiments of this application;

Figure 14 is a schematic diagram of the structural composition of the data transmission device provided in an embodiment of this application;

Figure 15 is a schematic diagram of the structure of the data transmission device provided in an embodiment of this application;

Figure 16 is a schematic diagram of the structure of the data transmission device provided in an embodiment of this application;

Figure 17 is a schematic diagram of the structure of the data transmission device provided in the embodiment of this application;

Figure 18 is a schematic diagram of the structure of the data transmission device provided in the embodiment of this application;

Figure 19 is a schematic diagram of the structure of the data transmission device provided in an embodiment of this application;

Figure 20 is a schematic structural diagram of a communication device provided in an embodiment of this application;

Figure 21 is a schematic structural diagram of a chip according to an embodiment of this application;

Figure 22 is a schematic block diagram of a communication system provided in an embodiment of this application.

Detailed Implementation

The technical solutions of the embodiments of this application will now be described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

Figure 1 is a schematic diagram of an application scenario of an embodiment of this application.

As shown in Figure 1, the communication system 100 may include a terminal device 110 and a network device 120. The network device 120 can communicate with the terminal device 110 via an air interface. Multi-service transmission is supported between the terminal device 110 and the network device 120.

It should be understood that the embodiments of this application are only illustrated by way of example with communication system 100, but the embodiments of this application are not limited thereto. That is to say, the technical solutions of the embodiments of this application can be applied to various communication systems, such as: Long Term Evolution (LTE) system, LTE Time Division Duplex (TDD), Universal Mobile Telecommunication System (UMTS), Internet of Things (IoT) system, Narrow Band Internet of Things (NB-IoT) system, enhanced Machine-Type Communications (eMTC) system, 5G communication system (also known as New Radio (NR) communication system), 6G communication system, or future communication systems, etc.

In the communication system 100 shown in Figure 1, network device 120 may be an access network device that communicates with terminal device 110. The access network device can provide communication coverage for a specific geographical area and can communicate with terminal device 110 (e.g., UE) located within that coverage area.

Network device 120 may be an evolved Node B (eNB or eNodeB) in a Long Term Evolution (LTE) system, a Next Generation Radio Access Network (NG RAN) device, a base station (gNB) in an NR system, a base station in a 6G system, a radio controller in a Cloud Radio Access Network (CRAN), or a relay station, access point, vehicle-mounted device, wearable device, hub, switch, bridge, router, or network device in a future evolved Public Land Mobile Network (PLMN), etc.

Terminal device 110 can be any terminal device, including but not limited to terminal devices that are connected to network device 120 or other terminal devices via wired or wireless connections.

For example, the terminal device 110 may refer to an access terminal, user equipment (UE), user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent, or user device. The access terminal may be a cellular phone, cordless phone, Session Initiation Protocol (SIP) phone, IoT device, satellite handheld terminal, Wireless Local Loop (WLL) station, Personal Digital Assistant (PDA), handheld device with wireless communication capabilities, computing device or other processing device connected to a wireless modem, vehicle-mounted device, wearable device, terminal device in a 5G network, terminal device in a 6G network, or terminal device in a future evolved network, etc.

Terminal device 110 can be used for device-to-device (D2D) communication.

The communication system 100 may further include a core network device 130 that communicates with the network device 120. The core network device 130 may be a 5G core network (5G Core, 5GC) device, such as an Access and Mobility Management Function (AMF), an Authentication Server Function (AUSF), a User Plane Function (UPF), or a Session Management Function (SMF). In some embodiments, the core network device 130 may also be an Evolved Packet Core (EPC) device for an LTE network, such as a session management function. This refers to a Session Management Function + Core Packet Gateway (SMF+PGW-C) device. It should be understood that SMF+PGW-C can simultaneously perform the functions of both SMF and PGW-C. During network evolution, the aforementioned core network device may also be called by other names, or new network entities may be formed by dividing the core network functions; this application does not impose any limitations on this.

The various functional units in the communication system 100 can also communicate with each other through a next-generation (NG) interface.

For example, terminal devices establish air interface connections with access network devices through the NR interface for transmitting user plane data and control plane signaling; terminal devices can establish control plane signaling connections with the AMF through NG interface 1 (N1); access network devices, such as next-generation radio access base stations (gNB), can establish user plane data connections with the UPF through NG interface 3 (N3); access network devices can establish control plane signaling connections with the AMF through NG interface 2 (N2); the UPF can establish control plane signaling connections with the SMF through NG interface 4 (N4); the UPF can interact with the data network for user plane data through NG interface 6 (N6); the AMF can establish control plane signaling connections with the SMF through NG interface 11 (N11); and the SMF can establish control plane signaling connections with the PCF through NG interface 7 (N7).

Figure 1 exemplarily illustrates a network device, a core network device, and two terminal devices. Optionally, the communication system 100 may include multiple network devices, and each network device may include other numbers of terminal devices within its coverage area. This application embodiment does not limit this.

It should be noted that Figure 1 is merely an example illustrating the system to which this application applies. Of course, the method shown in the embodiments of this application can also be applied to other systems. Furthermore, the terms "system" and "network" are often used interchangeably in this document. The term "and/or" in this document merely describes the relationship between related objects, indicating that three relationships can exist. For example, A and/or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character "/" in this document generally indicates that the preceding and following related objects have an "or" relationship. It should also be understood that "instruction" mentioned in the embodiments of this application can be a direct instruction, an indirect instruction, or an indication of a related relationship. For example, A instructing B can mean that A directly instructs B, for example, B can be obtained through A; it can also mean that A indirectly instructs B, for example, A instructs C, B can be obtained through C; or it can mean that there is a related relationship between A and B. It should also be understood that "correspondence" mentioned in the embodiments of this application can indicate a direct or indirect correspondence between two things, or an related relationship between two things, or a relationship of instruction and being instructed, configuration and being configured, etc. It should also be understood that the "predefined" or "predefined rules" mentioned in the embodiments of this application can be implemented by pre-storing corresponding codes, tables, or other means that can be used to indicate relevant information in the device (e.g., including terminal devices and network devices), and this application does not limit the specific implementation method. For example, predefined can refer to those defined in a protocol. It should also be understood that in the embodiments of this application, the "protocol" can refer to standard protocols in the field of communication, such as LTE protocol, NR protocol, and related protocols applied to future communication systems, and this application does not limit this.

To facilitate understanding of the technical solutions of the embodiments of this application, the relevant technologies of the embodiments of this application are described below. The following relevant technologies are optional solutions and can be combined with the technical solutions of the embodiments of this application in any way, and they all fall within the protection scope of the embodiments of this application.

1. Local data services and non-local data services

The "IMT-2030+ Vision and Requirements White Paper" mentions potential 6G application scenarios such as immersive experiences, digital twins, and intelligent interaction. Simultaneously, based on traditional performance indicators, it proposes extreme performance requirements such as ultra-high speed, ultra-high transmission reliability, ultra-low latency, ultra-dense connections, and ultra-low power consumption. However, simultaneously supporting these extreme performance requirements across the entire network would significantly increase network load and 6G operating costs, making it impractical. Considering that these specific application scenarios are typically deployed in smaller areas and have strong local data service attributes, deploying and providing localized, high-performance data service support within a small area is an important direction for meeting 6G scenario requirements. Wide-area/micro-domain convergence and subnetwork wireless access network concepts have been successively proposed by the industry in 6G. One approach is to aggregate terminal data within micro-domains, introducing a new cluster head node (HP) for each micro-domain. Micro-domain terminals can interact with the wide area network or other micro-domain terminals through the HP, thereby greatly reducing the load and maintenance costs of the wide area network and improving spectrum resource utilization.

Figure 2 is a schematic diagram of a micro-domain terminal (sub-UE) communicating with a wide area network (macro network) via HP according to an embodiment of this application.

Microdomain terminal/sub-UE service types can be divided into two categories: local services within the microdomain, which are services whose generation, transmission, and processing are all limited to the microdomain itself; and non-local services, which are services generated within the microdomain but processed outside the microdomain, or services generated outside the microdomain but targeted at a specific node within the microdomain. These types of services typically have medium latency requirements in the millisecond range or are latency-insensitive services, and can ultimately be processed via a wide area network.

Microdomain local service transmission includes data transmission between microdomain terminals and microdomain HPs, as well as optional data transmission between microdomain terminals (such as under the control and coordination of microdomain HPs). Compared with traditional WAN transmission, microdomain local service data has a shorter transmission path, making it easier to achieve extreme performance requirements such as ultra-low latency and ultra-high reliability. In a WAN-microdomain converged networking architecture, signaling connections between the microdomain HP (representing the entire microdomain network) and the WAN access network (AN) and WAN core network (CN) are required.

In addition to supporting local service transmission within the microdomain, it is also necessary to support non-local service transmission between microdomain terminals and the wide area network (WAN). This fully utilizes WAN cloud computing resources, balances the load between the microdomain and the WAN, and handles various services from microdomain terminals more effectively and flexibly. Furthermore, non-local microdomain services also include inter-microdomain service transmission, such as information transmission between terminals in one microdomain and terminals in another, or information transmission between two microdomain HPs. For non-local microdomain services, they can be forwarded to the WAN via microdomain HPs using a relay mode.

Currently, technologies that can support local data service processing include 5G Virtual Network (VN) groups, LTE Local IP Access (LIPA)/Selected IP Traffic Offload (SIPTO), and Rel-19 Wireless Access Backhaul (WAB).

2. WAB

Figure 3 is a schematic diagram of the deployment of WAB technology provided in the embodiments of this application.

Currently, research on WAB technology is underway in the Rel-19 phase. Similar to Rel-18 Mobile IAB, WAB is still based on the assumption of single-hop backhaul. In addition to UE functionality (WAB-MT), WAB nodes also possess complete gNB functionality (WAB-gNB). WAB can provide local services to WAB nodes by deploying a local UPF alongside the WAB node with complete gNB functionality; however, whether Rel-19 WAB supports local deployment of UPF functionality on WAB nodes is still under discussion.

3. 5G VN group/5G LAN (Local Area Network)

As shown in Figure 4, the 5G Virtual-Network Group (5G VN Group) is a key concept in 5G networks used to implement 5G LAN-type services. Through 5G VN groups, enterprises or organizations can create a private, isolated network space, enabling member UEs to communicate with each other and access shared resources, similar to a traditional LAN environment. 5G VN groups provide a mechanism that allows a type of data traffic from a specific application or service entering or leaving a terminal to be offloaded near the access network connection point to which the terminal is attached, without affecting other traffic entering or leaving the same terminal. Traffic forwarding within a 5G VN group is implemented through the UPF's internal interface, "5G VN internal," which employs a two-step process of detection and forwarding to ensure that data packets are correctly forwarded from the sender to the receiver. 5G VN groups are identified and distinguished by 5G VN group identities, supporting unicast, broadcast, and multicast communication services, enabling member UEs to enjoy a rich communication experience. Member UEs access 5G VN groups through Protocol Data Unit (PDU) sessions. Each session provides access to only one 5G VN group. UEs do not need to specially mark data packets, thus avoiding impact on UEs and reducing the burden on UE implementation.

In 5G networks, the SMF is responsible for configuring the UPF to apply different traffic forwarding methods, thereby enabling data routing between PDU sessions within a single 5G VN group.

Figure 5 is a schematic diagram of several data forwarding methods of UPF provided in the embodiments of this application. As shown in Figure 5, the data forwarding methods of UPF include: local forwarding, N6-based forwarding, and N19-based forwarding.

1) Local forwarding: If different member UEs within a 5G VN group share the same UPF, traffic can be forwarded locally through that UPF. This means that traffic does not need to be forwarded through an external interface, but is routed directly within the local UPF.

2) N6-based forwarding: In this method, uplink and downlink traffic within the 5G VN group is forwarded to or from the data network via the N6 interface connecting the core network and the data network.

3) N19-based forwarding: When uplink and downlink traffic within a 5G VN group needs to be forwarded between different UPFs, the N19 interface is used. N19 is a shared user plane tunnel connecting UPFs within the same 5G VN group, allowing for efficient traffic forwarding between different sessions within the group.

Overall, the 5G VN group implements a local service forwarding scheme at the UPF level. These local service forwarding methods enable 5G networks to flexibly handle traffic routing needs in different scenarios, whether within the local UPF or through communication with external networks or different UPFs via the N6 or N19 interfaces. This is suitable for 5G application scenarios that require LAN characteristics.

4. LTE LIPA/SIPTO

Local IP Access (LIPA) and Selected IP Traffic Offload (SIPTO) are service flow data management functions proposed in LTE. They have basically the same functions and network architecture, and solve similar problems. They are used to realize service localization and close-range deployment, avoid core network data transmission bottlenecks, and bring low latency and high bandwidth transmission capabilities to the mobile network to meet users' needs for high-speed data access and innovative services.

LIPA and SIPTO were initially proposed based on home or enterprise network base stations (H(e)NB). Later, SIPTO was extended to apply to macro networks for traffic offloading. LIPA allows UEs in home or enterprise networks to directly access resources within their home/enterprise network via the H(e)NB by deploying a local gateway (L-GW) near the H(e)NB, without requiring the user plane to traverse through any operator network other than the H(e)NB. SIPTO, on the other hand, allows for the offloading of specific services near the location where the UE attaches to the access network, enabling direct internet access via the H(e)NB or macro base station. SIPTO can achieve traffic offloading within the local network by selecting a local gateway deployed alongside the (H)eNB or a separate gateway, or by selecting a gateway geographically or topologically close to the location where the UE attaches to the access network to achieve traffic offloading via the mobile operator's core network packet data network gateway (P-GW).

Figure 6 illustrates a scenario where a local gateway (L-GW) function and a home or enterprise network base station (H(e)NB) are deployed together. Architecture diagram of LIPA or SIPTO.

Overall, LTE LIPA/SIPTO also implements a gateway-level local service forwarding scheme. To better support local service forwarding, LTE LIPA/SIPTO technology requires the gateway to be moved down to the access network side.

The above provides a brief explanation of the relevant technologies/terms involved in this application, which will not be repeated in the following embodiments.

Currently, the routing of local service data requires the participation of the core network. For example, for local service data from terminal #1 to terminal #2, the data transmission must pass through: terminal #1, base station (gNB), User Plane Function (UPF), base station (gNB), and terminal #2 in sequence. It is evident that the local service data sent by terminal #1 needs to be forwarded by the UPF, resulting in a relatively long data transmission delay.

In view of this, this application provides a data transmission method, apparatus, device, chip, and storage medium. In this method, a terminal device may send first information to a head node. The first information is used to request or indicate switching the transmission mode of first data to a target transmission mode. The first data is sent by a first sub-terminal and received by a second sub-terminal. The target transmission mode is either a first transmission mode or a second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

According to the method in the embodiments of this application, the transmission mode of the first data can be switched to a first transmission mode or a second transmission mode through a first information request or instruction. In the first transmission mode, the first data can be forwarded (or routed) by the head node without needing to be forwarded by the core network equipment. Therefore, by switching the transmission mode of the first data, it is possible to flexibly control whether the first data needs to be forwarded by the core network equipment, thereby flexibly controlling the transmission delay of the first data.

To facilitate understanding of the technical solutions of the embodiments of this application, the technical solutions of this application are described in detail below through specific embodiments. The above-mentioned related technologies are optional solutions and can be arbitrarily combined with the technical solutions of the embodiments of this application, all of which fall within the protection scope of the embodiments of this application. The embodiments of this application include at least some of the following contents.

Figure 7 is a schematic flowchart of a data transmission method provided in an embodiment of this application. As shown in Figure 7, the method may include the following steps:

S701, the first sub-terminal sends first information to the head node. The first information is used to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In this embodiment, the first sub-terminal can send first information to the head node, and correspondingly, the head node can receive the first information from the first sub-terminal. The first information can be used to request or instruct switching the transmission mode of the first data to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal.

In other words, the first sub-terminal can request or instruct the head node to switch the transmission mode of the first data to the target transmission mode by sending the first information. The first data can also be understood as data sent from the first sub-terminal (source terminal) to the second sub-terminal (target terminal).

In some embodiments, switching the transmission mode of the first data to the target transmission mode means switching the transmission mode of the first data from the third transmission mode to the target transmission mode. In this case, the first information can be used to request or instruct the switching of the transmission mode of the first data from the third transmission mode to the target transmission mode. One possible scenario is that the third transmission mode is the first transmission mode and the target transmission mode is the second transmission mode; another possible scenario is that the third transmission mode is the second transmission mode and the target transmission mode is the first transmission mode.

In some embodiments, the target transmission method may be a first transmission method or a second transmission method.

In some embodiments, when the first data is transmitted using the first transmission mode, the first data can be sent to the second sub-terminal via the header node. That is, when the first data is transmitted using the first transmission mode, the devices the first data passes through during transmission include: the first sub-terminal, the header node, and the second sub-terminal. Under this transmission mode, the first data may not need to be forwarded by the core network equipment, thereby reducing the transmission latency of the first data. Therefore, by switching the transmission mode of the first data, whether the first data needs to be forwarded by the core network equipment can be flexibly controlled, thereby flexibly controlling the transmission latency of the first data.

For example, when the transmission method of the first data is the first transmission method, the devices that the first data passes through during transmission may include: a first sub-terminal, a head node, and a second sub-terminal. Figure 8(a) illustrates an example of the first transmission method. As shown in Figure 8(a), the first sub-terminal can send the first data to the head node, and then the head node can send it to the second sub-terminal. In some scenarios, the first transmission method may also be referred to as the "local transmission method".

In the embodiments of this application, the head node may be, for example, a base station or a Radio Access Network (RAN) node.

In some embodiments, when the transmission mode of the first data is the second transmission mode, the first data can be sent to the second sub-terminal through the head node and the core network equipment.

For example, when the first data is transmitted using the second transmission method, the devices that the first data passes through during transmission may include: a first sub-terminal, a header node, a core network device, a header node, and a second sub-terminal. Figure 8(b) illustrates an example of the second transmission method. In some scenarios, the second transmission method may also be referred to as a "non-local transmission method".

In some embodiments, the target transmission method is a second transmission method (non-local transmission method).

In some embodiments, when the target transmission mode is the second transmission mode (non-local transmission mode), the first sub-terminal sends first information to the head node, including sending the first information to the head node when a first condition is met. Or, in other words, in If the first condition is met, the first sub-terminal may determine to switch the transmission mode of the first data to the second transmission mode (for example, switch from the first transmission mode to the second transmission mode).

For example, the first condition may include one or more of the following 11) to 18):

11) The upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode.

In other words, if the upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode, the first sub-terminal can send the first information to the head node to request or instruct to switch the transmission mode of the first data to the target transmission mode.

In some embodiments, the granularity indicated by the upper layer (i.e., the granularity of the first data) can be a first granularity. That is, the upper layer can instruct the transmission mode of the first granularity data sent from the first sub-terminal to the second sub-terminal to be switched to the target transmission mode.

As an example, the first granularity can be one of the following:

Service flow granularity, that is, the first data can be a service flow, or correspond to a service flow;

QoS flow granularity, that is, the first data can be a QoS flow, or correspond to a QoS flow;

Service type granularity, that is, the first data can be data corresponding to a certain (or several) service types;

Service granularity, that is, the first data can be data corresponding to a certain (or several) services. In this case, the first data can correspond to the identifier (ID) of that certain (or several) services.

PDU session granularity, that is, the first data can be a PDU session;

The granularity of the connection refers to the fact that the first data can be data transmitted through the first connection, and the first connection can be a connection between the first sub-terminal and the second sub-terminal.

12) The packet delay budget (PDB) of the first data is greater than or equal to the first threshold.

In other words, if the PDB of the first data is greater than or equal to the first threshold, the first sub-terminal can send the first information to the head node to request or instruct the transmission mode of the first data to be switched to the target transmission mode.

Understandably, if the PDB of the first data is large, the transmission latency requirement for the first data can be considered low (i.e., the allowable transmission latency is relatively high). Therefore, it is not necessary to use the first transmission method (local transmission method) to transmit the first data. In this case, switching the transmission method of the first data to the second transmission method (non-local transmission method) helps to reduce the load on the head node.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the second sub-terminal, i.e., the end-to-end PDB (E2E PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment; the PDB of the first data transmitted from the head node to the second sub-terminal, which may be provided by the head node, for example.

In some embodiments, in determining whether the PDB of the first data is greater than or equal to the first threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; bearer granularity; Radio Link Control (RLC) channel granularity; logical channel granularity; packet granularity.

In some embodiments, the determination process can be performed at the Service Data Adaptation Protocol (SDAP)/Packet Data Convergence Protocol (PDCP)/RLC/Media Access Control (MAC) layer.

In some embodiments, the first threshold may be configured by the head node (e.g., via dedicated Radio Resource Control (RRC) signaling or System Information Block (SIB)), pre-configured, defined by the protocol, or indicated by an upper layer.

In some embodiments, the configuration granularity of the first threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data priority level granularity; or Reference Signal Receiving Power (RSRP) level granularity. In some embodiments, the first threshold can be configured uniformly, that is, without distinguishing granularity.

As an example, if the configuration granularity of the first threshold is QoS flow granularity, it means that the first threshold can be used to determine whether the PDB of the first data of the QoS flow granularity is greater than or equal to the first threshold.

As another example, if the configuration granularity of the first threshold is the data priority level granularity, it means that the same first threshold can be applied to data with the same priority. For example, if the first threshold corresponding to data priority #1 is threshold #1, then if the priority of the first data is data priority #1, the first sub-terminal can determine whether the PDB of the first data is greater than or equal to threshold #1. If it is greater than or equal to threshold #1, then the first information can be sent.

As another example, if the configuration granularity of the first threshold is RSRP level granularity, it means that the first data transmitted within the same geographical area corresponding to the same RSRP level can be subject to the same first threshold. For example, if the RSRP level within geographical area #1 is level #1, and the first threshold corresponding to level #1 is threshold #2, then if the first sub-terminal is located within geographical area #1 when sending the first data, the first sub-terminal can determine whether the PDB of the first data is greater than or equal to threshold #2. If it is greater than or equal to threshold #2, then the first information can be sent.

The meanings of the other configuration granularities of the first threshold can be understood by referring to the above examples, and will not be repeated here.

13) The link signal quality between the first sub-terminal and the head node is less than or equal to the second threshold.

In other words, if the link signal quality between the first sub-terminal and the head node is less than or equal to the second threshold, then the first sub-terminal can send a signal to the head node. The node sends a first message to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The link signal quality between the first sub-terminal and the head node can be obtained, for example, from the measurement results of Layer 1 (L1) or Layer 3 (L3).

In some embodiments, the second threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the second threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the second threshold can be configured uniformly, that is, without distinguishing granularity.

14) The link signal quality between the head node and the second sub-terminal is less than or equal to the third threshold.

In other words, if the link signal quality between the head node and the second sub-terminal is less than or equal to the third threshold, the first sub-terminal can send first information to the head node to request or instruct the transmission mode of the first data to be switched to the target transmission mode. The link signal quality between the head node and the second sub-terminal can be obtained, for example, based on measurements from Layer 1 or Layer 3.

In some embodiments, the second threshold and the third threshold may be the same or different.

It is understandable that in some scenarios, the second and third thresholds may differ due to the different uplink and downlink transmission powers (different power control mechanisms) and the different data transmission capabilities of terminal devices (such as the first sub-terminal) and head nodes.

In some embodiments, the third threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the third threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the third threshold can be configured uniformly, that is, without distinguishing granularity.

15) The link signal quality between the first sub-terminal and the second sub-terminal is less than or equal to the fourth threshold.

In other words, if the link signal quality between the first sub-terminal and the second sub-terminal is less than or equal to the fourth threshold, the first sub-terminal can send first information to the head node to request or instruct the transmission mode of the first data to be switched to the target transmission mode. The link signal quality between the first sub-terminal and the second sub-terminal can be obtained, for example, based on measurements from Layer 1 or Layer 3.

In some embodiments, the first sub-terminal can obtain the link signal quality by measuring one or more of the following information sent by the second sub-terminal: data channel information; control channel information; discovery information; synchronization information; and reference signal information.

In some embodiments, the fourth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the fourth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the fourth threshold can be configured uniformly, that is, without distinguishing granularity.

It is understandable that if situations 13), 14), and 15) occur, it means that the distance between the first sub-terminal and the second sub-terminal may be far, or that the first sub-terminal and the second sub-terminal may not belong to the same local business group. In this case, the processing latency requirement for the first data is low (that is, the allowable latency is relatively high). Therefore, it is not necessary to use the first transmission method (local transmission method) to transmit the first data.

16) Within a first duration, a first number of negative feedbacks (such as negative feedbacks of PDCP/RLC/Hybrid Automatic Repeat reQuest, HARQ) are continuously received from the head node and/or the second sub-terminal, and the first number is greater than or equal to the fifth threshold.

For example, if the first sub-terminal receives N consecutive negative feedbacks from the head node within the first time period, and N is greater than or equal to the fifth threshold, then the first sub-terminal may send the first information to the head node.

In another example, if the first sub-terminal receives N consecutive negative feedbacks from the second sub-terminal within the first time period, and N is greater than or equal to the fifth threshold, then the first sub-terminal may send the first information to the head node.

In another example, if the first sub-terminal receives N consecutive negative feedbacks (which may include negative feedbacks from the head node and the second sub-terminal) within the first time period, and N is greater than or equal to the fifth threshold, then the first sub-terminal may send the first information to the head node.

Understandably, if the first sub-terminal receives a large number of negative feedbacks from the head node and/or the second sub-terminal within the first time period, it indicates that the reliability of data transmission using the first transmission mode (local transmission mode) is poor. Therefore, the transmission mode of the first data can be switched to the second transmission mode (non-local transmission mode). Under the second transmission mode, since the first data needs to pass through the core network equipment, the core network equipment can adopt certain strategies to improve the transmission reliability of the first data.

17) The first event occurs on the first sub-terminal.

18) The first event occurs in the second sub-terminal.

In other words, if the first sub-terminal and/or the second sub-terminal experience a first event, the first sub-terminal may send first information to the head node. The first event may include one of the following: Radio Link Failure (RLF), Handover (HO), RRC connection reconstruction, or Beam Failure (BF).

In some embodiments, whether a first event has occurred in the second sub-terminal can be indicated to the first sub-terminal by the head node.

It is understandable that if the first event occurs in the first sub-terminal and/or the second sub-terminal, it indicates that the connection status between the first sub-terminal and/or the second sub-terminal and the head node may change. Therefore, if the first transmission method is used, the first data may not be successfully sent to the second sub-terminal. Thus, the transmission method of the first data can be switched to the second transmission method.

In some embodiments, the target transmission method is the first transmission method (local transmission method).

In some embodiments, when the target transmission mode is the first transmission mode (local transmission mode), the first sub-terminal sends a data to the header terminal. Sending the first information includes, under the condition that the second condition is met, the first sub-terminal sending the first information to the head node. Alternatively, under the condition that the second condition is met, the first sub-terminal may determine to switch the transmission mode of the first data to the first transmission mode (e.g., switch from the second transmission mode to the first transmission mode).

For example, the second condition may include one or more of the following 21) to 26):

21) The upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode.

In other words, if the upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode, the first sub-terminal can send the first information to the head node to request or instruct to switch the transmission mode of the first data to the target transmission mode.

In some embodiments, the granularity indicated by the upper layer (i.e., the granularity of the first data) can be a first granularity. That is, the upper layer can instruct the transmission mode of the first granularity data sent from the first sub-terminal to the second sub-terminal to be switched to the target transmission mode. As an example, the first granularity can be one of the following: service flow granularity; QoS flow granularity; service type granularity; service granularity; PDU session granularity; connection granularity.

22) The PDB of the first data is less than or equal to the sixth threshold.

In other words, if the PDB of the first data is less than or equal to the sixth threshold, the first sub-terminal can send the first information to the head node to request or instruct the transmission mode of the first data to be switched to the target transmission mode.

It is understandable that when the PDB of the first data is small, the transmission latency requirement for the first data is considered to be high (that is, the transmission latency requirement is low). Therefore, the transmission mode of the first data can be switched to the first transmission mode (local transmission mode) to reduce the transmission latency of the first data.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the second sub-terminal, i.e., the end-to-end PDB (E2E PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment; the PDB of the first data transmitted from the head node to the second sub-terminal, which may be provided by the head node, for example.

In some embodiments, in determining whether the PDB of the first data is less than or equal to the sixth threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data packet granularity.

In some embodiments, this determination process can be performed at the SDAP/PDCP/RLC/MAC layer.

In some embodiments, the sixth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB configuration), or pre-configured, or defined by the protocol, or indicated by an upper layer.

In some embodiments, the configuration granularity of the sixth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data priority level granularity; RSRP level granularity. In some embodiments, the sixth threshold can be configured uniformly, that is, without distinguishing granularity.

23) The link signal quality between the first sub-terminal and the head node is greater than or equal to the seventh threshold.

In other words, if the link signal quality between the first sub-terminal and the head node is greater than or equal to the seventh threshold, the first sub-terminal can send first information to the head node to request or instruct the transmission mode of the first data to be switched to the target transmission mode. The link signal quality between the first sub-terminal and the head node can be obtained, for example, based on measurements from Layer 1 or Layer 3.

In some embodiments, the seventh threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the seventh threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the seventh threshold can be configured uniformly, that is, without distinguishing granularity.

24) The link signal quality between the head node and the second sub-terminal is greater than or equal to the eighth threshold.

In other words, if the link signal quality between the head node and the second sub-terminal is greater than or equal to the eighth threshold, the first sub-terminal can send first information to the head node to request or instruct the transmission mode of the first data to be switched to the target transmission mode. The link signal quality between the head node and the second sub-terminal can be obtained, for example, based on measurements from Layer 1 or Layer 3.

In some embodiments, the eighth threshold and the seventh threshold may be the same or different.

In some embodiments, the eighth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the eighth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the eighth threshold can be configured uniformly, that is, without distinguishing granularity.

25) The link signal quality between the first sub-terminal and the second sub-terminal is greater than or equal to the ninth threshold.

In other words, if the link signal quality between the first sub-terminal and the second sub-terminal is greater than or equal to the ninth threshold, the first sub-terminal can send first information to the head node to request or instruct the transmission mode of the first data to be switched to the target transmission mode. The link signal quality between the first sub-terminal and the second sub-terminal can be obtained, for example, based on measurements from Layer 1 or Layer 3.

In some embodiments, the first sub-terminal can obtain the link signal quality by measuring one or more of the following information sent by the second sub-terminal: data channel information; control channel information; discovery information; synchronization information; and reference signal information.

In some embodiments, the ninth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the ninth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the ninth threshold can be configured uniformly, that is, without distinguishing granularity.

Understandably, if situations 23), 24), and 25) occur, it indicates that the distance between the first and second sub-terminals may be relatively short, or that the first and second sub-terminals may belong to the same local service group. In this case, the first data is local service data, thus requiring lower transmission latency. By switching the transmission mode of the first data to the first transmission mode (local transmission mode), the transmission latency of the first data can be reduced.

26) Within a first time period, a first number of positive feedbacks (such as positive feedbacks from PDCP/RLC/HARQ) are continuously received from the head node and/or the first sub-terminal, and the first number is greater than or equal to the tenth threshold.

It is understandable that if the first sub-terminal receives a large number of positive feedbacks from the head node and/or the second sub-terminal within the first time period, it indicates that the reliability of data transmission using the local transmission method is high. Therefore, the transmission method of the first data can be switched to the first transmission method (local transmission method), thereby reducing the transmission latency of the first data while ensuring the transmission reliability of the first data.

In some embodiments, the method further includes: a first sub-terminal receiving second information from a head node. The second information is used to indicate the link signal quality between the head node and the second sub-terminal.

For example, the head node may send second information to the first sub-terminal before receiving first information from the first sub-terminal. Correspondingly, the first sub-terminal may receive second information from the head node before sending the first information to the head node. Thus, the first sub-terminal can determine whether it is necessary to switch the transmission mode of the first data to the target transmission mode based on the link signal quality between the head node and the second sub-terminal.

In some embodiments, the link signal quality between the head node and the second sub-terminal can be measured by the second sub-terminal. The second sub-terminal, provided that the network configuration's measurement reporting conditions are met, can report the measurement results (i.e., the link signal quality between the head node and the second sub-terminal) to the head node. Then, the head node can send second information to the first sub-terminal to indicate the link signal quality between the head node and the second sub-terminal. This second information can be carried, for example, through RRC signaling, a MAC control element (MAC CE), or downlink control information (DCI).

As an example, the above measurement reporting conditions may include: the predetermined time for reporting the measurement result has arrived. For example, if the measurement result is reported periodically, then if the time interval between the last reported measurement result and the last reported measurement result reaches one cycle, the predetermined time for reporting the measurement result can be considered to have arrived, at which point the second sub-terminal can report the measurement result to the head node again.

In another example, the measurement reporting conditions described above may include the triggering of a specific event. That is, if a specific event is triggered, the second sub-terminal may report the measurement results to the head node. In some embodiments, the specific event may be configured by the head node.

In some embodiments, the method may further include: the head node sending fourth information to the core network device.

For example, after receiving the first information from the first sub-terminal, the head node may, in response to the first information, send a fourth information to the core network device. Correspondingly, the core network device may receive the fourth information from the head node. The fourth information may be used to request or indicate switching the transmission mode of the first data to the target transmission mode.

In some embodiments, after receiving the fourth information from the head node, the core network device may, in response to the fourth information, send the fifth information and/or the fourth configuration to the head node. Accordingly, the head node may receive the fifth information and/or the fourth configuration from the core network device.

In some embodiments, the fifth information may be used to indicate switching the transmission mode of the first data to the target transmission mode.

In some embodiments, the fourth configuration can be used by the head node to send first data from the first sub-terminal using the target transmission method.

For example, when the target transmission method is the second transmission method (non-local transmission method), the fourth configuration can be used to configure the non-local path/policy/mapping of the first data. Thus, after the head node receives the first data from the first sub-terminal, it can send (forward) the first data from the first sub-terminal using the non-local transmission method based on the fourth configuration.

For example, when the target transmission mode is the first transmission mode (local transmission mode), the fourth configuration can be used to configure the local path/policy/mapping of the first data. Thus, after the head node receives the first data from the first sub-terminal, it can send (forward) the first data from the first sub-terminal using the local transmission mode based on the fourth configuration.

In some embodiments, the method may further include: the head node sending third information to the first sub-terminal, and correspondingly, the first sub-terminal receiving the third information from the head node. The third information may be used to indicate switching the transmission mode of the first data to the target transmission mode.

In one possible approach, after receiving the first information from the first sub-terminal, the head node can respond to the first information by sending a third information to the first sub-terminal. In this case, the head node may not need to send a fourth information to the core network equipment.

In another possible approach, after receiving the first information from the first sub-terminal, the head node can send the fourth information to the core network device, and after receiving the fifth information and/or the fourth configuration from the core network device, send the third information to the first sub-terminal.

In some embodiments, the method may further include: a head node sending a first configuration to a first sub-terminal, and correspondingly, the first sub-terminal receiving the first configuration from the head node. The first configuration can be used by the first sub-terminal to send first data using a target transmission mode. Thus, after receiving the first configuration from the head node, the first sub-terminal can send the first data using the target transmission mode based on the first configuration.

In some embodiments, the first configuration is related to the fourth configuration. That is, the header node can determine the first configuration based on the fourth configuration from the core network equipment, and then send the first configuration to the first sub-terminal.

In some embodiments, the head node may determine the first configuration on its own. For example, if the core network device does not send the fourth configuration to the head node, the head node may determine the first configuration on its own and send the first configuration to the first sub-terminal.

In some embodiments, the first configuration may include one or more of the following:

Bearer configuration (or reconfiguration);

RLC channel configuration (or reconfiguration);

Logical channel configuration (or reconfiguration);

Configure (or reconfigure) the resource settings (or grant permissions, CG).

Security configuration (or reconfiguration) (such as key configuration/reconfiguration).

In some embodiments, the first information may include one or more of the following 31) to 34):

31) Information about the first data, that is, information about the data that needs to be switched to the target transmission mode.

For example, if the first data is a data stream/QoS stream/bearer/RLC channel/logical channel/data packet/PDU session, the information in the first data can be the information (such as the identifier) of that data stream/QoS stream/bearer/RLC channel/logical channel/data packet/PDU session.

For example, if the first data is data transmitted through the first connection, the information in the first data can be information about the first connection (such as an identifier). The first connection can be a connection between a first sub-terminal and a second sub-terminal.

32) Reason for switching.

For example, if the target transmission mode is the second transmission mode (non-local transmission mode), the reason for switching may include one or more of the reasons in 11) to 18) above.

For example, if the target transmission mode is the first transmission mode (local transmission mode), the reason for switching may include one or more of the reasons in 21) to 28) above.

33) Link signal quality between the first sub-terminal and the head node.

34) Link signal quality between the first sub-terminal and the second sub-terminal.

In some embodiments, the first information is first data, the configuration used by the first sub-terminal when sending the first data, and/or the header information of the first data, used to request or indicate that the transmission mode of the first data be switched to the target transmission mode.

In some embodiments, before receiving the first information from the first sub-terminal, the head node may send a second configuration and a third configuration to the first sub-terminal. Correspondingly, before sending the first information to the head node, the first sub-terminal may receive the second configuration and the third configuration from the head node. The second configuration can be used by the first sub-terminal to send first data using a first transmission method; the third configuration can be used by the first sub-terminal to send first data using a second transmission method.

In other words, the head node can pre-configure the first sub-terminal with a configuration for sending the first data using a first transmission mode and a second transmission mode. Alternatively, the head node can pre-configure the first sub-terminal with a configuration for sending the first data using a local transmission mode and a configuration for sending the first data using a non-local transmission mode. Thus, if the first sub-terminal determines to switch the transmission mode of the first data to the first transmission mode, it can use the second configuration to send the first data (first information) to the head node; if the first sub-terminal determines to switch the transmission mode of the first data to the second transmission mode, it can use the third configuration to send the first data (first information) to the head node. Therefore, the head node can identify whether the transmission mode of the first data has been switched to the target transmission mode based on the configuration used by the first sub-terminal when sending the first data (first information) and/or the packet header information of the first data.

For example, if the first sub-terminal uses the second configuration when sending the first data, the head node can know that the transmission mode of the first data has been switched to the first transmission mode. In other words, the head node can know that the first data (first information) is used to request or indicate that the transmission mode of the first data has been switched to the first transmission mode.

In another example, if the first sub-terminal uses the third configuration when sending the first data, the head node can know that the transmission mode of the first data has been switched to the second transmission mode. In other words, the head node can know that the first data (first information) is used to request or indicate that the transmission mode of the first data has been switched to the second transmission mode.

In some embodiments, when the target transmission mode is the second transmission mode (non-local transmission mode), if the first information is the first data, the header node can send the first data to the core network device.

In other words, if the head node learns that it needs to switch the transmission mode of the first data to a non-local transmission mode, and if the head node receives the first data from the first sub-terminal, it can send the first data to the core network device. For example, after receiving the first data from the first sub-terminal, if a non-local path for the first data already exists (i.e., a path used to transmit the first data from the head node to the core network device in non-local transmission mode), the head node can send the first data to the core network device through this non-local path. In this case, the head node does not need to send the fourth information to the core network device.

In some embodiments, the granularity of the first data can be one of the following:

Service flow granularity, that is, the first data can be a service flow, or correspond to a service flow;

QoS flow granularity, that is, the first data can be a QoS flow, or correspond to a QoS flow;

The granularity of the load, that is, the first data can be the load, or correspond to the load;

Data packet granularity, that is, the first data can be a data packet, or correspond to a data packet;

RLC channel granularity, that is, the first data can be an RLC channel, or correspond to an RLC channel;

Logical channel granularity, that is, the first data can be a logical channel, or correspond to a logical channel;

Service type granularity, that is, the first data can be data corresponding to a certain (or several) service types;

Service granularity, that is, the first data can be data corresponding to a certain (or several) services;

PDU session granularity, that is, the first data can be a PDU session, or correspond to a PDU session;

Connection granularity, that is, the first data can be data transmitted through the first connection, and the first connection can be a connection between the first sub-terminal and the second sub-terminal.

According to the method of this embodiment, a terminal device (such as a first sub-terminal) can switch the transmission mode of the first data to the target transmission mode by sending a first information request or instruction. In other words, the terminal device can decide whether to switch the transmission mode of the first data, thereby enhancing its decision-making power and enabling it to flexibly control the transmission latency of the first data. Furthermore, the terminal device's autonomous determination of whether to switch the transmission mode of the first data also reduces the process of reporting signaling to the head node to a certain extent, thus reducing signaling overhead.

Figure 9 is a schematic flowchart of the data transmission method provided in an embodiment of this application. As shown in Figure 9, the method may include the following steps:

S901, the head node sends first information to the first sub-terminal. The first information is used to indicate that the transmission mode of the first data is switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In this embodiment, the head node can send first information to the first sub-terminal, and correspondingly, the first sub-terminal can receive the first information from the head node. The first information can be used to instruct the transmission mode of the first data to be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal.

In other words, the head node can send first information to the first sub-terminal to instruct it to switch the transmission mode of the first data to the target transmission mode. The first data can also be understood as data sent from the first sub-terminal (source terminal) to the second sub-terminal (target terminal).

In some embodiments, the target transmission method can be a first transmission method (local transmission method) or a second transmission method (non-local transmission method).

In some embodiments, when the first data is transmitted using the first transmission mode, the first data can be sent to the second sub-terminal via the header node. That is, when the first data is transmitted using the first transmission mode, the devices the first data passes through during transmission include: the first sub-terminal, the header node, and the second sub-terminal. Under this transmission mode, the first data may not need to be forwarded by the core network equipment, thereby reducing the transmission latency of the first data. Therefore, by switching the transmission mode of the first data, whether the first data needs to be forwarded by the core network equipment can be flexibly controlled, thereby flexibly controlling the transmission latency of the first data.

In some embodiments, when the transmission mode of the first data is the second transmission mode, the first data can be sent to the second sub-terminal through the head node and the core network equipment.

Further details regarding the first transmission method (local transmission method) and the second transmission method (non-local transmission method) can be found in the relevant descriptions in the brief embodiments, and will not be repeated here.

In some embodiments, the target transmission method is a second transmission method (non-local transmission method).

In some embodiments, when the target transmission mode is the second transmission mode (non-local transmission mode), the head node may determine whether to switch the transmission mode of the first data to the target transmission mode according to one or more of the following 41) to 48) before sending the first information to the first sub-terminal.

41) The first data PDB.

For example, if the PDB of the first data is large (e.g., greater than a certain threshold), the head node can determine to switch the transmission mode of the first data to the target transmission mode.

Understandably, if the PDB of the first data is large, the transmission latency requirement for the first data can be considered low (i.e., the allowable transmission latency is relatively high). Therefore, it is not necessary to use the first transmission method (local transmission method) to transmit the first data. In this case, switching the transmission method of the first data to the second transmission method (non-local transmission method) helps to reduce the load on the head node.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the second sub-terminal (denoted as the first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment (denoted as the second PDB); the PDB of the first data transmitted from the core network equipment to the head node (denoted as the third PDB); and the PDB of the first data transmitted from the head node to the second sub-terminal.

The first PDB and the second PDB may be provided by the first sub-terminal, for example; the third PDB may be provided by the core network equipment, for example.

42) Link signal quality between the first sub-terminal and the head node.

For example, if the link signal quality between the first sub-terminal and the head node is low (e.g., below a certain threshold), the head node can determine to switch the transmission mode of the first data to the target transmission mode.

43) Link signal quality between the head node and the second sub-terminal.

For example, if the link signal quality between the head node and the second sub-terminal is low (e.g., below a certain threshold), the head node can determine to switch the transmission mode of the first data to the target transmission mode.

44) Link signal quality between the first sub-terminal and the second sub-terminal.

For example, if the link signal quality between the first sub-terminal and the second sub-terminal is low (e.g., below a certain threshold), the head node... It can be determined that the transmission mode of the first data will be switched to the target transmission mode.

It is understandable that if the link signal quality between the first sub-terminal and the head node is low, or the link signal quality between the head node and the second sub-terminal is low, or the link signal quality between the first sub-terminal and the second sub-terminal is low, it indicates that the distance between the first sub-terminal and the second sub-terminal may be far, or that the first sub-terminal and the second sub-terminal may not belong to the same local service group. In this case, the processing latency requirement for the first data is low (i.e., the allowable latency is relatively high). Therefore, it is not necessary to use the first transmission method (local transmission method) to transmit the first data.

45) The number of negative feedbacks (such as negative feedbacks of PDCP/RLC/HARQ) continuously received from the first sub-terminal and/or the second sub-terminal within the first time period.

For example, if the head node receives N consecutive negative feedbacks from the first sub-terminal and/or the second sub-terminal within the first time period, it can be determined that the transmission mode of the first data should be switched to the target transmission mode.

Understandably, if the head node receives a large number of negative feedbacks from the first sub-terminal and/or the second sub-terminal within the first time period, it indicates that the reliability of data transmission using the first transmission mode (local transmission mode) is poor. Therefore, the transmission mode of the first data can be switched to the second transmission mode (non-local transmission mode). Under the second transmission mode, since the first data needs to pass through the core network equipment, the core network equipment can adopt certain strategies to improve the transmission reliability of the first data.

46) Load status of the head node.

For example, if the head node has a high load, it can be determined to switch the transmission mode of the first data to the target transmission mode (second transmission mode) to reduce the load on the head node.

47) Whether the first sub-terminal has experienced a first event, the first event includes one of the following: RLF, HO, RRC connection reconstruction, BF.

For example, if the first event occurs in the first sub-terminal, the head node can determine to switch the transmission mode of the first data to the target transmission mode.

48) Whether the second sub-terminal has experienced a first event, the first event including one of the following: RLF, HO, RRC connection reconstruction, BF.

For example, if the first event occurs in the second sub-terminal, the head node can determine to switch the transmission mode of the first data to the target transmission mode.

It is understandable that if the first event occurs in the first sub-terminal and/or the second sub-terminal, it indicates that the connection status between the first sub-terminal and/or the second sub-terminal and the head node may change. Therefore, if the first transmission method is used, the first data may not be successfully sent to the second sub-terminal. Thus, the transmission method of the first data can be switched to the second transmission method.

In some embodiments, when the target transmission mode is the second transmission mode (non-local transmission mode), the method may further include: the head node sending first data from the first sub-terminal to the core network device.

In other words, if the head node determines to switch the transmission mode of the first data to the target transmission mode, then after receiving the first data from the first sub-terminal, the head node can send the first data to the core network device. For example, after receiving the first data from the first sub-terminal, if a non-local path for the first data already exists (that is, a path used to transmit the first data from the head node to the core network device in a non-local transmission mode), then the head node can send the first data to the core network device through this non-local path.

In some embodiments, the target transmission method is the first transmission method (local transmission method).

In some embodiments, when the target transmission mode is the first transmission mode (local transmission mode), the head node may determine whether to switch the transmission mode of the first data to the target transmission mode according to one or more of the following 51) to 56) before sending the first information to the first sub-terminal.

51) The first data PDB.

For example, if the PDB of the first data is small (e.g., less than a certain threshold), the head node can determine to switch the transmission mode of the first data to the target transmission mode.

It is understandable that when the PDB of the first data is small, the transmission latency requirement for the first data is considered to be high (that is, the transmission latency requirement is low). Therefore, the transmission mode of the first data can be switched to the first transmission mode (local transmission mode) to reduce the transmission latency of the first data.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the second sub-terminal (denoted as the first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment (denoted as the second PDB); the PDB of the first data transmitted from the core network equipment to the head node (denoted as the third PDB); and the PDB of the first data transmitted from the head node to the second sub-terminal.

The first PDB and the second PDB may be provided by the first sub-terminal, for example; the third PDB may be provided by the core network equipment, for example.

52) Link signal quality between the first sub-terminal and the head node.

For example, if the link signal quality between the first sub-terminal and the head node is high (e.g., greater than a certain threshold), the head node can determine to switch the transmission mode of the first data to the target transmission mode.

53) Link signal quality between the head node and the second sub-terminal.

For example, if the link signal quality between the head node and the second sub-terminal is high (e.g., greater than a certain threshold), the head node can determine to switch the transmission mode of the first data to the target transmission mode.

54) Link signal quality between the first sub-terminal and the second sub-terminal.

For example, if the link signal quality between the first sub-terminal and the second sub-terminal is high (e.g., greater than a certain threshold), the head node... It can be determined that the transmission mode of the first data will be switched to the target transmission mode.

Understandably, if the link signal quality between the first sub-terminal and the head node is high, or the link signal quality between the head node and the second sub-terminal is high, or the link signal quality between the first sub-terminal and the second sub-terminal is high, it indicates that the distance between the first and second sub-terminals may be relatively short, or that the first and second sub-terminals may belong to the same local service group. In this case, the first data is local service data, and therefore requires lower transmission latency. By switching the transmission mode of the first data to the first transmission mode (local transmission mode), the transmission latency of the first data can be reduced.

55) The number of positive feedbacks (such as positive feedbacks from PDCP/RLC/HARQ) continuously received from the first sub-terminal and/or the second sub-terminal within the first time period;

For example, if the head node receives N consecutive positive feedbacks from the first sub-terminal and/or the second sub-terminal within the first time period, it can be determined to switch the transmission mode of the first data to the target transmission mode.

Understandably, if the head node receives a large number of positive feedbacks from the first sub-terminal and/or the second sub-terminal within the first time period, it indicates that the reliability of data transmission using the local transmission method is high. Therefore, the transmission method of the first data can be switched to the first transmission method (local transmission method), thereby reducing the transmission latency of the first data while ensuring the transmission reliability of the first data.

56) Load status of the head node.

For example, if the load on the head node is small, it can be determined to switch the transmission mode of the first data to the target transmission mode (the first transmission mode) to reduce the transmission latency of the first data.

In some embodiments, the method may further include: the first sub-terminal sending the PDB of the first data to the head node. (For example, the first sub-terminal may send the PDB of the first data before receiving the first information from the head node).

The PDB of the first data may include, for example, the PDB of the first data transmitted from the first sub-terminal to the second sub-terminal (first PDB); and/or, the PDB of the first data transmitted from the first sub-terminal to the core network equipment (second PDB). Therefore, the head node can determine whether to switch the transmission mode of the first data to the target transmission mode based on the PDB of the first data.

In some embodiments, the first sub-terminal may send the PDB of the first data to the head node if a first condition is met.

For example, when the target transmission mode is the second transmission mode (non-local transmission mode), the first condition may include: the PDB of the first data is greater than or equal to a first threshold. That is, if the PDB of the first data is greater than or equal to the first threshold, the first sub-terminal may send the PDB of the first data to the head node.

For example, when the target transmission mode is the first transmission mode (local transmission mode), the first condition may include: the PDB of the first data is less than or equal to a second threshold. That is, if the PDB of the first data is less than or equal to the second threshold, the first sub-terminal may send the PDB of the first data to the head node.

In some embodiments, when the first sub-terminal determines whether the PDB of the first data is greater than or equal to a first threshold, and/or when it determines whether the PDB of the first data is less than or equal to a second threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data packet granularity.

In some embodiments, the above determination process can be performed at the SDAP/PDCP/RLC/MAC layer.

In some embodiments, the first threshold/second threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB configuration), or pre-configured, or defined by the protocol, or indicated by the upper layer.

In some embodiments, the configuration granularity of the first threshold/second threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data priority level granularity; RSRP level granularity. In some embodiments, the first threshold/second threshold can be configured uniformly, that is, without distinguishing granularity.

In some embodiments, the method may further include: the first sub-terminal sending the measurement result to the head node (for example, the first sub-terminal may send the measurement result before receiving the first information from the head node).

The measurement results may include, for example, the link signal quality between the first sub-terminal and the head node, and/or the link signal quality between the first sub-terminal and the second sub-terminal. Therefore, the head node can determine, based on the measurement results, whether to switch the transmission mode of the first data to the target transmission mode.

In some embodiments, the first sub-terminal may send the measurement results to the head node if a second condition is met.

In some embodiments, the second condition may include: the predetermined time for reporting the measurement result has arrived. For example, if the measurement result is reported periodically, then if the time interval between the last reported measurement result and the last reported measurement result reaches one cycle, the predetermined time for reporting the measurement result can be considered to have arrived, at which point the first sub-terminal can send the measurement result to the head node again.

In some embodiments, the second condition may include: a specific event being triggered. That is, if a specific event is triggered, the first sub-terminal may send the measurement result to the head node. In some embodiments, the specific event may be configured by the head node.

For example, when the target transmission method is the second transmission method (non-local transmission method), the specific event may include: the measurement result is less than or equal to a third threshold. That is, if the measurement result is less than or equal to the third threshold, the first sub-terminal may send the measurement result to the head node.

For example, when the target transmission method is the first transmission method (local transmission method), this specific event may include: measurement. The result is greater than or equal to the fourth threshold. That is, if the measurement result is greater than or equal to the fourth threshold, the first sub-terminal can send the measurement result to the head node.

In some embodiments, the third/fourth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the third threshold/fourth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the third threshold/fourth threshold can be configured uniformly, that is, without distinguishing granularity.

In some embodiments, the method may further include: the head node receiving one or more of the following 61) to 64) information (e.g., receiving it before sending the first information to the first sub-terminal):

61) The first data PDB.

For example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the second sub-terminal (first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network device (second PDB); and the PDB of the first data transmitted from the core network device to the head node (third PDB). The first and second PDBs may be provided, for example, by the first sub-terminal; and the third PDB may be provided, for example, by the core network device.

62) Link signal quality between the first sub-terminal and the head node. This information may be provided by the first sub-terminal, for example.

63) Link signal quality between the head node and the second sub-terminal. This information may be provided by the second sub-terminal, for example.

64) Link signal quality between the first sub-terminal and the second sub-terminal. This information may be provided by the first sub-terminal, for example.

Furthermore, the head node can determine whether to switch the transmission mode of the first data to the target transmission mode based on one or more of the information in 61) to 64).

In some embodiments, before the head node sends the first information to the first sub-terminal, the method may further include: the head node sending second information to the core network device, and correspondingly, the core network device may receive the second information from the head node. The second information is used to request or indicate switching the transmission mode of the first data to the target transmission mode.

In some embodiments, after receiving the second information from the head node, the core network device may, in response to the second information, send the third information and/or the first configuration to the head node. Accordingly, the head node may receive the third information and/or the first configuration from the core network device.

In some embodiments, the third information may be used to indicate switching the transmission mode of the first data to the target transmission mode.

In some embodiments, the first configuration can be used by the head node to send first data from the first sub-terminal using the target transmission method.

For example, when the target transmission mode is the second transmission mode (non-local transmission mode), the first configuration can be used to configure the non-local path of the first data. Thus, after the head node receives the first data from the first sub-terminal, it can send (forward) the first data from the first sub-terminal using the non-local transmission mode based on the first configuration.

For example, when the target transmission mode is the first transmission mode (local transmission mode), the first configuration can be used to configure the local path of the first data. Thus, after the head node receives the first data from the first sub-terminal, it can send (forward) the first data from the first sub-terminal using the local transmission mode based on the first configuration.

In some embodiments, the method may further include: the head node sending a second configuration to the first sub-terminal, and correspondingly, the first sub-terminal receiving the second configuration from the head node. The second configuration can be used by the first sub-terminal to send first data using a target transmission mode. Thus, after receiving the second configuration from the head node, the first sub-terminal can send the first data using the target transmission mode based on the second configuration.

In some embodiments, the second configuration is related to the first configuration. That is, the header node can determine the second configuration based on the first configuration from the core network equipment, and then send the second configuration to the first sub-terminal.

In some embodiments, the head node may determine the second configuration on its own. For example, if the core network device does not send the first configuration to the head node, the head node may determine the second configuration on its own and send the second configuration to the first sub-terminal.

In some embodiments, the second configuration may include one or more of the following:

Bearer configuration (or reconfiguration);

RLC channel configuration (or reconfiguration);

Logical channel configuration (or reconfiguration);

CG resource configuration (or reconfiguration);

Security configuration (or reconfiguration) (such as key configuration/reconfiguration).

In some embodiments, the method may further include: the head node sending a third configuration and a fourth configuration to the first sub-terminal (e.g., the head node may send the third configuration and the fourth configuration before sending the first information to the first sub-terminal). Accordingly, the first sub-terminal may receive the third configuration and the fourth configuration from the head node (e.g., the terminal device may receive the third configuration and the fourth configuration before receiving the first information from the head node). The third configuration may be used by the first sub-terminal to send first data using a first transmission method; the fourth configuration may be used by the first sub-terminal to send first data using a second transmission method.

In other words, the head node can pre-configure the first sub-terminal with a configuration to send the first data using a first transmission method and a second transmission method. Alternatively, the head node can pre-configure the first sub-terminal with a configuration to send the first data using a local transmission method, and a configuration to send the first data using a non-local transmission method. Configuration for sending the first data.

Furthermore, if the head node determines to switch the transmission mode of the first data to the target transmission mode, it can send the first information to the first sub-terminal to instruct it to switch the transmission mode of the first data to the target transmission mode.

In some embodiments, the first information may include information about the first data. Thus, after receiving the first information, the first sub-terminal can determine, according to the indication of the first information, that the data requiring switching to the target transmission mode is the first data, and can then send the first data using the corresponding configuration (third configuration or fourth configuration).

The information in the first data can be, for example, the identifier (ID) corresponding to the first data.

For example, if the first data is a QoS stream/bearer/logical channel, the information in the first data can be the identifier of that QoS stream/bearer/logical channel.

For example, if the first data is data transmitted through the first connection, the information of the first data can be the identifier of the first connection. The first connection can be a connection between a first sub-terminal and a second sub-terminal.

In some embodiments, the method may further include: a first sub-terminal sending first data to a head node using a target transmission mode. Accordingly, the head node may receive the first data from the first sub-terminal. Further, the head node may send (forward) the first data from the first sub-terminal using the target transmission mode.

In some embodiments, the granularity of the first data can be one of the following:

Service flow granularity, that is, the first data can be a service flow, or correspond to a service flow;

QoS flow granularity, that is, the first data can be a QoS flow, or correspond to a QoS flow;

The granularity of the load, that is, the first data can be the load, or correspond to the load;

Data packet granularity, that is, the first data can be a data packet, or correspond to a data packet;

RLC channel granularity, that is, the first data can be an RLC channel, or correspond to an RLC channel;

Logical channel granularity, that is, the first data can be a logical channel, or correspond to a logical channel;

Service type granularity, that is, the first data can be data corresponding to a certain (or several) service types;

Service granularity, that is, the first data can be data corresponding to a certain (or several) services;

PDU session granularity, that is, the first data can be a PDU session, or correspond to a PDU session;

Connection granularity, that is, the first data can be data transmitted through the first connection, and the first connection can be a connection between the first sub-terminal and the second sub-terminal.

According to the method of this embodiment, the head node can switch the transmission mode of the first data to the target transmission mode by sending a first information indication. In other words, whether to switch the transmission mode of the first data can be determined by the head node. Since the head node, as an intermediate node for data forwarding, can know the status of the two links (the link between the first sub-terminal and the head node, and the link between the head node and the second sub-terminal), it has better control over the Access Stratum (AS) configuration/resources. Therefore, having the head node determine whether to switch the transmission mode of the first data is beneficial to ensuring the overall stability of the communication system.

Figure 10 is a schematic flowchart of the data transmission method provided in this application embodiment. As shown in Figure 10, the method may include the following steps:

S1001, the core network device sends first information to the head node. The first information is used to indicate that the transmission mode of the first data is switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In this embodiment, the core network device can send first information to the head node, and correspondingly, the head node can receive the first information from the core network device. The first information can be used to instruct switching the transmission mode of the first data to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal.

In other words, core network equipment can send first information to the head node to instruct the transmission mode of the first data to be switched to the target transmission mode. The first data can also be understood as data sent from the first sub-terminal (source terminal) to the second sub-terminal (target terminal).

In some embodiments, the target transmission method can be a first transmission method (local transmission method) or a second transmission method (non-local transmission method).

In some embodiments, when the first data is transmitted using the first transmission mode, the first data can be sent to the second sub-terminal via the header node. That is, when the first data is transmitted using the first transmission mode, the devices the first data passes through during transmission include: the first sub-terminal, the header node, and the second sub-terminal. Under this transmission mode, the first data may not need to be forwarded by the core network equipment, thereby reducing the transmission latency of the first data. Therefore, by switching the transmission mode of the first data, whether the first data needs to be forwarded by the core network equipment can be flexibly controlled, thereby flexibly controlling the transmission latency of the first data.

In some embodiments, when the transmission mode of the first data is the second transmission mode, the first data can be sent to the second sub-terminal through the head node and the core network equipment.

Further details regarding the first transmission method (local transmission method) and the second transmission method (non-local transmission method) can be found in the relevant descriptions in the brief embodiments, and will not be repeated here.

In some embodiments, the target transmission method is a second transmission method (non-local transmission method).

In some embodiments, the target transmission method is the first transmission method (local transmission method).

In some embodiments, before sending the first information to the head node, the core network device may determine whether to switch the transmission mode of the first data to the target transmission mode according to one or more of the following 71) to 74).

71) The first data PDB.

For example, if the target transmission mode is the second transmission mode (non-local transmission mode), and the PDB of the first data is large (e.g., greater than a certain threshold), the core network device can determine to switch the transmission mode of the first data to the target transmission mode. As another example, if the target transmission mode is the first transmission mode (local transmission mode), and the PDB of the first data is small (e.g., less than a certain threshold), the core network device can determine to switch the transmission mode of the first data to the target transmission mode.

Understandably, if the PDB of the first data is large, the transmission latency requirement for the first data can be considered low (i.e., the allowable transmission latency is relatively high). Therefore, it is not necessary to use the first transmission method (local transmission method) to transmit the first data. In this case, switching the transmission method of the first data to the second transmission method (non-local transmission method) helps to reduce the load on the head node.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the second sub-terminal (denoted as the first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment (denoted as the second PDB); the PDB of the first data transmitted from the core network equipment to the head node; and the PDB of the first data transmitted from the head node to the second sub-terminal (denoted as the third PDB).

In some embodiments, the method may further include: the core network device receiving the PDB of the first data (e.g., the core network device may receive the PDB of the first data before sending the first information to the head node).

In some embodiments, the first PDB and the second PDB may be provided by the first sub-terminal.

For example, when the target transmission mode is the second transmission mode (non-local transmission mode), the first sub-terminal may send the first PDB and/or the second PDB to the head node if the first PDB and/or the second PDB is greater than or equal to the first threshold.

For example, when the target transmission mode is the first transmission mode (local transmission mode), the first sub-terminal may send the first PDB and/or the second PDB to the head node if the first PDB and/or the second PDB are less than or equal to the second threshold.

In some embodiments, when the first sub-terminal determines whether the first PDB and/or the second PDB is greater than or equal to the first threshold, and/or when it determines whether the first PDB and/or the second PDB is less than or equal to the second threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; packet granularity; PDU session granularity.

In some embodiments, the third PDB may be provided by the header node. For example, the header node may send the PDB (third PDB) of the first data to the core network device before receiving the first information from the core network device.

72) Has the first sub-terminal been switched over?

For example, if the target transmission mode is the second transmission mode (non-local transmission mode), and the first sub-terminal switches, the core network equipment can determine to switch the transmission mode of the first data to the target transmission mode.

73) Has the second sub-terminal been switched over?

For example, if the target transmission mode is the second transmission mode (non-local transmission mode), and the second sub-terminal switches, the core network equipment can determine to switch the transmission mode of the first data to the target transmission mode.

It is understandable that if the first sub-terminal and/or the second sub-terminal switch, it means that the connection status between the first sub-terminal and/or the second sub-terminal and the head node has changed. Therefore, if the first transmission mode (local transmission mode) is used, the first data may not be successfully sent to the second sub-terminal. Thus, the transmission mode of the first data can be switched to the second transmission mode (non-local transmission mode).

74) Load status of core network equipment.

For example, if the target transmission mode is the second transmission mode (non-local transmission mode), and the core network device has a low load, the core network device can determine to switch the transmission mode of the first data to the target transmission mode in order to reduce the load on the head node.

In another example, if the target transmission mode is the first transmission mode (local transmission mode), and the core network device has a high load, the core network device can determine to switch the transmission mode of the first data to the target transmission mode in order to reduce the load of the core network device and reduce the transmission latency of the first data.

In some embodiments, the method may further include: the core network device sending a first configuration to the head node. Accordingly, the head node may receive the first configuration from the core network device. The first configuration may be used by the head node to send first data from the first sub-terminal using a target transmission mode.

For example, when the target transmission mode is the second transmission mode (non-local transmission mode), the first configuration can be used to configure the non-local path of the first data. Thus, after the head node receives the first data from the first sub-terminal, it can send (forward) the first data from the first sub-terminal using the non-local transmission mode based on the first configuration.

For example, when the target transmission mode is the first transmission mode (local transmission mode), the first configuration can be used to configure the local path of the first data. Thus, after the head node receives the first data from the first sub-terminal, it can send (forward) the first data from the first sub-terminal using the local transmission mode based on the first configuration.

In some embodiments, the method may further include: the head node sending second information to the first sub-terminal, and correspondingly, the first sub-terminal may... Receive second information from the head node. This second information can be used to indicate switching the transmission mode of the first data to the target transmission mode.

In some embodiments, the second information may include: information about the first data, such as an identifier corresponding to the first data. The information about the first data can be used to indicate that the data for which the transmission mode needs to be switched is the first data.

In some embodiments, the method may further include: the head node sending a second configuration to the first sub-terminal, and correspondingly, the first sub-terminal receiving the second configuration from the head node. The second configuration can be used by the first sub-terminal to send first data using a target transmission mode. Thus, after receiving the second configuration from the head node, the first sub-terminal can send the first data using the target transmission mode based on the second configuration.

In some embodiments, the second configuration is related to the first configuration. That is, the header node can determine the second configuration based on the first configuration from the core network equipment, and then send the second configuration to the first sub-terminal.

In some embodiments, the head node may determine the second configuration on its own. For example, if the core network device does not send the first configuration to the head node, the head node may determine the second configuration on its own and send the second configuration to the first sub-terminal.

In some embodiments, the second configuration may include one or more of the following:

Bearer configuration (or reconfiguration);

RLC channel configuration (or reconfiguration);

Logical channel configuration (or reconfiguration);

CG resource configuration (or reconfiguration);

Security configuration (or reconfiguration) (such as key configuration/reconfiguration).

In some embodiments, the method may further include: the head node sending a third configuration and a fourth configuration to the first sub-terminal (e.g., the head node may send the third configuration and the fourth configuration before receiving the first information from the core network device). Accordingly, the first sub-terminal may receive the third configuration and the fourth configuration from the head node. The third configuration may be used by the first sub-terminal to send first data using a first transmission method; the fourth configuration may be used by the first sub-terminal to send first data using a second transmission method.

In other words, the head node can pre-configure the first sub-terminal with a configuration to send the first data using a first transmission method and a second transmission method. Alternatively, the head node can pre-configure the first sub-terminal with a configuration to send the first data using a local transmission method and a configuration to send the first data using a non-local transmission method.

Furthermore, if the core network device determines to switch the transmission mode of the first data to the target transmission mode, it can send the first information to the head node to instruct the first data to switch to the target transmission mode.

In some embodiments, the first information may include information about the first data, such as an identifier corresponding to the first data. Thus, after receiving the first information, the head node can determine, based on the indication of the first information, that the data requiring switching to the target transmission mode is the first data.

Furthermore, the head node can send a second message to the first sub-terminal to instruct it to switch the transmission mode of the first data to the target transmission mode. Upon receiving the second message, the first sub-terminal can then determine, based on the instruction in the second message, that it needs to switch the transmission mode of the first data to the target transmission mode, and thus can use the corresponding configuration (third configuration or fourth configuration) to send the first data.

In some embodiments, the granularity of the information in the first data indicated in the first information and the granularity of the information in the first data indicated in the second information may be the same or different.

In some embodiments, the granularity of the first data can be one of the following:

Service flow granularity, that is, the first data can be a service flow, or correspond to a service flow;

QoS flow granularity, that is, the first data can be a QoS flow, or correspond to a QoS flow;

The granularity of the load, that is, the first data can be the load, or correspond to the load;

Data packet granularity, that is, the first data can be a data packet, or correspond to a data packet;

RLC channel granularity, that is, the first data can be an RLC channel, or correspond to an RLC channel;

Logical channel granularity, that is, the first data can be a logical channel, or correspond to a logical channel;

Service type granularity, that is, the first data can be data corresponding to a certain (or several) service types;

Service granularity, that is, the first data can be data corresponding to a certain (or several) services;

PDU session granularity, that is, the first data can be a PDU session, or correspond to a PDU session;

Connection granularity, that is, the first data can be data transmitted through the first connection, and the first connection can be a connection between the first sub-terminal and the second sub-terminal.

According to the method of this embodiment, the core network device can switch the transmission mode of the first data to the target transmission mode by sending a first information instruction. In other words, the core network device can decide whether to switch the transmission mode of the first data. Since data not passing through the core network may raise concerns among various parties regarding data security and traffic billing, having the core network device determine whether to switch the transmission mode of the first data can alleviate these concerns to some extent.

The data transmission method provided in the embodiments of this application has been described above. To facilitate understanding of the embodiments of this application, the following describes possible implementation schemes of the data transmission method applicable to the embodiments of this application, with reference to examples.

Figure 11 is a schematic diagram of a possible implementation flow of the data transmission method provided in an embodiment of this application. As shown in Figure 11, the implementation flow may include the following steps:

S1101, the first sub-terminal sends the first request/indication information to the head node (such as xNB).

The first request/instruction information can be used to request/instruct switching of the transmission mode of data sent from the first sub-terminal to the target terminal. In some embodiments, the first request/instruction information can also be used to request reconfiguration of the header node (RRC reconfiguration). As an example, the first request/instruction information can be RRC signaling, MAC CE, or Uplink Control Information (UCI) information.

For ease of explanation, the data sent from the first sub-terminal to the target terminal will be referred to as the first data in the following text. In the embodiments of this application, the target terminal may be, for example, a second sub-terminal.

In some embodiments, the first request/instruction information can be used to request/instruct switching the transmission mode of the first data to the target transmission mode.

In one implementation (denoted as implementation #11), the target transmission mode is a non-local transmission mode. That is, the first request/instruction information can be used to request/instruct switching the transmission mode of the first data to a non-local transmission mode (e.g., switching from a local transmission mode to a non-local transmission mode).

In another implementation (denoted as implementation #12), the target transmission mode is the local transmission mode. That is, the first request/instruction information can be used to request/instruct switching the transmission mode of the first data to the local transmission mode (e.g., switching from a non-local transmission mode to a local transmission mode).

It should be understood that the descriptions of local and non-local transmission methods can be found in the foregoing embodiments, and will not be repeated here.

In some embodiments, the first information may include one or more of the following a1) to a3):

a1) Information about the first data, that is, information about the data that needs to be switched.

For example, information about the data stream/QoS stream/bearer/RLC channel/logical channel/data packet/PDU session/link that needs to be switched. Among these, the information about the connection that needs to be switched is specifically the information about the connection used to transmit the first data.

a2) Reason for switching.

a3) Measurement report.

Measurement reports may include, for example, the link signal quality from the first sub-terminal to the head node, and/or the link signal quality from the first sub-terminal to the target terminal.

For implementation #11, the first sub-terminal may send a first request/indication message to the head node if a first condition is met. Exemplarily, the first condition may include one or more of the following b1) to b8):

b1) The upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode.

In other words, if the upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode, the first sub-terminal can send the first request/instruction information to the head node.

In some embodiments, the granularity indicated by the upper layer (i.e., the granularity of the first data) can be the first granularity. That is, the upper layer can instruct the transmission mode of the first granularity data sent from the first sub-terminal to the target terminal to be switched to the target transmission mode.

As an example, the first granularity can be one of the following: service flow granularity; QoS flow granularity; service type granularity; service granularity (that is, the data to be switched corresponds to the service ID); PDU session granularity; connection granularity (that is, the data to be switched corresponds to the connection between the first sub-terminal and the target terminal, or in other words, the data to be switched is the data transmitted through that connection).

b2) The PDB of the first data is greater than or equal to the first threshold.

In other words, if the PDB of the first data is greater than or equal to the first threshold, the first sub-terminal can send the first request/indication information to the head node.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the target terminal (E2E PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment; and the PDB of the first data transmitted from the head node to the target terminal.

In some embodiments, in determining whether the PDB of the first data is greater than or equal to the first threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; packet granularity.

In some embodiments, this determination process can be performed at the SDAP/PDCP/RLC/MAC layer.

In some embodiments, the first threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB), pre-configured, defined by the protocol, or indicated by an upper layer.

In some embodiments, the configuration granularity of the first threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data priority level granularity; RSRP level granularity. In some embodiments, the first threshold can be configured uniformly, that is, without distinguishing granularity.

b3) The link signal quality from the first sub-terminal to the head node is less than or equal to the second threshold.

In other words, if the link signal quality from the first sub-terminal to the head node is less than or equal to the second threshold, the first sub-terminal may send a first request/indication message to the head node. The link signal quality from the first sub-terminal to the head node can be determined, for example, based on Layer 1 (L1) or Layer 3 (L3). The measurement results were obtained.

In some embodiments, the second threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the second threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the second threshold can be configured uniformly, that is, without distinguishing granularity.

b4) The link signal quality from the head node to the target terminal is less than or equal to the third threshold.

In other words, if the link signal quality from the head node to the target terminal is less than or equal to the third threshold, the first sub-terminal can send a first request/indication message to the head node. The link signal quality from the head node to the target terminal can be obtained, for example, based on the measurement results of layer 1 (L1) or layer 3 (L3).

In some embodiments, the second threshold and the third threshold may be the same or different.

It is understandable that in some scenarios, the second and third thresholds may differ due to the different uplink and downlink transmission powers (different power control mechanisms) and the different data transmission capabilities of terminal devices (such as the first sub-terminal) and head nodes.

In some embodiments, the third threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the third threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the third threshold can be configured uniformly, that is, without distinguishing granularity.

In some embodiments, the link signal quality from the head node to the target terminal can be measured by the target terminal. The target terminal can report the measurement results to the head node if the network-configured measurement reporting conditions are met. The head node then instructs the first sub-terminal (e.g., via RRC signaling, MAC CE, or DCI signaling). The measurement reporting conditions may include, for example, periodic reporting or event-based reporting.

b5) The link signal quality from the first sub-terminal to the target terminal is less than or equal to the fourth threshold.

In other words, if the link signal quality from the first sub-terminal to the target terminal is less than or equal to the fourth threshold, the first sub-terminal may send a first request/indication message to the head node. The link signal quality from the first sub-terminal to the target terminal can be obtained, for example, based on the measurement results of layer 1 (L1) or layer 3 (L3).

In some embodiments, the first sub-terminal can obtain the link signal quality by measuring one or more of the following information sent by the target terminal: data channel information; control channel information; discovery information; synchronization information; and reference signal information.

In some embodiments, the fourth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the fourth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the fourth threshold can be configured uniformly, that is, without distinguishing granularity.

b6) The first sub-terminal experiences RLF, HO, RRC connection reconstruction or BF.

In other words, if the first sub-terminal experiences RLF, HO, RRC connection reconstruction, or BF, the first sub-terminal can send a first request/indication message to the head node. That is, in the event of RLF, HO, RRC connection reconstruction, or BF in the first sub-terminal, the transmission mode of the first data can default to the non-local transmission mode.

b7) The target terminal experiences RLF, HO, RRC connection reconstruction or BF.

In other words, if the target terminal experiences RLF, HO, RRC connection reconstruction, or BF, the first sub-terminal can send a first request/indication message to the head node. That is, in the event of RLF, HO, RRC connection reconstruction, or BF at the target terminal, the transmission mode of the first data can default to a non-local transmission mode.

In some embodiments, whether the target terminal has experienced RLF, HO, RRC connection reconstruction or BF can be indicated to the first sub-terminal by the head node.

b8) Within a certain time period, the first sub-terminal receives N consecutive negative feedbacks from the head node and/or the target terminal via PDCP/RLC/HARQ.

For implementation #12, the first sub-terminal may send a first request/indication message to the head node if the second condition is met. Exemplarily, the second condition may include one or more of the following c1) to c6):

c1) The upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode.

In other words, if the upper layer of the first sub-terminal instructs to switch the transmission mode of the first data to the target transmission mode, the first sub-terminal can send the first request/instruction information to the head node.

In some embodiments, the granularity indicated by the upper layer (i.e., the granularity of the first data) can be the first granularity. That is, the upper layer can instruct the transmission mode of the first granularity data sent from the first sub-terminal to the target terminal to be switched to the target transmission mode.

As an example, the first granularity can be one of the following: service flow granularity; QoS flow granularity; service type granularity; service granularity (that is, the data to be switched corresponds to the service ID); PDU session granularity; connection granularity (that is, the data to be switched corresponds to the connection between the first sub-terminal and the target terminal, or in other words, the data to be switched is the data transmitted through that connection).

c2) The PDB of the first data is less than or equal to the sixth threshold.

In other words, if the PDB of the first data is less than or equal to the sixth threshold, the first sub-terminal can send the first request/indication information to the head node.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the target terminal (E2E PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment; and the PDB of the first data transmitted from the head node to the target terminal.

In some embodiments, in determining whether the PDB of the first data is less than or equal to the sixth threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data packet granularity.

In some embodiments, this determination process can be performed at the SDAP/PDCP/RLC/MAC layer.

In some embodiments, the sixth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB configuration), or pre-configured, or defined by the protocol, or indicated by an upper layer.

In some embodiments, the configuration granularity of the sixth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data priority level granularity; RSRP level granularity. In some embodiments, the sixth threshold can be configured uniformly, that is, without distinguishing granularity.

c3) The link signal quality from the first sub-terminal to the head node is greater than or equal to the seventh threshold.

In other words, if the link signal quality from the first sub-terminal to the head node is greater than or equal to the seventh threshold, the first sub-terminal may send a first request/indication message to the head node. The link signal quality from the first sub-terminal to the head node can be obtained, for example, based on measurements from Layer 1 or Layer 3.

In some embodiments, the seventh threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the seventh threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the seventh threshold can be configured uniformly, that is, without distinguishing granularity.

c4) The link signal quality from the head node to the target terminal is greater than or equal to the eighth threshold.

In other words, if the link signal quality from the head node to the target terminal is greater than or equal to the eighth threshold, the first sub-terminal can send a first request/indication message to the head node. The link signal quality from the head node to the target terminal can be obtained, for example, based on measurements from Layer 1 or Layer 3.

In some embodiments, the seventh threshold and the eighth threshold may be the same or different.

Understandably, in some scenarios, the seventh and eighth thresholds may differ due to differences in uplink and downlink transmission power (different power control mechanisms) and the different data transmission capabilities of terminal devices (such as the first sub-terminal) and head nodes.

In some embodiments, the eighth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the eighth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the eighth threshold can be configured uniformly, that is, without distinguishing granularity.

In some embodiments, the link signal quality from the head node to the target terminal can be measured by the target terminal. The target terminal can report the measurement results to the head node if the network-configured measurement reporting conditions are met. The head node then instructs the first sub-terminal (e.g., via RRC signaling, MAC CE, or DCI signaling). The measurement reporting conditions may include, for example, periodic reporting or event-based reporting.

c5) The link signal quality from the first sub-terminal to the target terminal is greater than or equal to the ninth threshold.

In other words, if the link signal quality from the first sub-terminal to the target terminal is greater than or equal to the ninth threshold, the first sub-terminal may send a first request/indication message to the head node. The link signal quality from the first sub-terminal to the target terminal can be obtained, for example, based on the measurement results of Layer 1 (L1) or Layer 3 (L3).

In some embodiments, the first sub-terminal can obtain the link signal quality by measuring one or more of the following information sent by the target terminal: data channel information; control channel information; discovery information; synchronization information; and reference signal information.

In some embodiments, the ninth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the ninth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the ninth threshold can be configured uniformly, that is, without distinguishing granularity.

c6) Within a certain time period, the first sub-terminal receives N consecutive positive feedbacks from the head node and/or the target terminal via PDCP/RLC/HARQ.

S1102, the header node sends a second request/instruction message to the core network equipment.

After receiving the first request/instruction information from the first sub-terminal, the head node can send a second request/instruction information to the core network equipment. The second request/instruction information can be used to request/instruct switching the transmission mode of the first data to the target transmission mode.

In some embodiments, for implementation #11, if a non-local path exists for the first data (i.e., a path for transmitting the first data from the head node to the core network device in a non-local transmission mode), the head node, after receiving the first data from the first sub-terminal, can send the first data to the core network device through this non-local path. In this case, the head node does not need to send the second request/indication information to the core network device, that is, it does not need to execute S1102. Correspondingly, if a non-local path for the first data does not exist, the head node needs to send the second request/indication information to the core network device.

S1103, the core network equipment sends third indication information and/or first configuration to the head node.

The third indication information can be used to instruct the transmission mode of the first data to be switched to the target transmission mode. The first configuration can be used by the head node to send (forward) the first data from the first sub-terminal using the target transmission mode.

For example, in implementation #11, the first configuration can be used to configure the non-local path/policy/mapping of the first data, so that the head node can send (forward) the first data from the first sub-terminal using a non-local transmission method based on the first configuration.

For example, in implementation #12, the first configuration can be used to configure the local path/policy/mapping of the first data, so that the head node can send (forward) the first data from the first sub-terminal using the local transmission method based on the first configuration.

S1104, the head node sends the fourth indication information and/or the second configuration to the first sub-terminal.

In this step, the head node may send a fourth indication message and/or a second configuration (reconfiguration message) to the first sub-terminal.

The fourth instruction information can be used to instruct the first data transmission mode to be switched to the target transmission mode. The second configuration can be used by the first sub-terminal to send the first data using the target transmission mode.

In some embodiments, the header node may determine the second configuration based on the first configuration, or, if the core network device does not send the first configuration, the header node may determine the second configuration on its own.

In some embodiments, the second configuration may configure (or reconfigure) one or more of the following for the transmission of the first data:

Bearer configuration (reconfiguration);

RLC channel configuration (reconfiguration);

Logical channel configuration (reconfiguration);

CG resource configuration (reconfiguration);

Security configuration (reconfiguration) (such as key configuration/reconfiguration).

S1105, the first sub-terminal sends the first data using the target transmission method.

In this step, the first sub-terminal can send the first data using the target transmission method based on the second configuration.

It should be noted that in some embodiments, steps S1102 and S1103 can be omitted (not executed). That is, after receiving the first request/indication information, the head node may not need to send the second request/indication information to the core network device. Correspondingly, the core network device may not need to send the third indication information and/or the first configuration to the head node. In this case, after receiving the first request/indication information, the head node may, in response to the first request/indication information, send the fourth indication information and/or the second configuration to the first sub-terminal.

In some embodiments, the head node can pre-configure the first sub-terminal with configurations for sending the first data in both local and non-local transmission modes. For example, before the first sub-terminal sends the first request/instruction information, the head node has already configured the first sub-terminal with a configuration for sending the first data in local transmission mode (denoted as the third configuration) and a configuration for sending the first data in non-local transmission mode (denoted as the fourth configuration). In this case, the first sub-terminal does not need to wait for the head node to send the second configuration. If the first condition is met, the first sub-terminal can directly use the fourth configuration to send the first data; if the second condition is met, the first sub-terminal can directly use the third configuration to send the first data. Thus, the head node can identify whether the transmission mode of the first data has been switched based on the configuration used by the first sub-terminal when sending the first data and/or the header of the first data packet. For example, if the head node identifies that the first sub-terminal is using the third configuration when sending the first data, it can know that the transmission mode of the first data has switched to local transmission mode; or, for example, if the head node identifies that the first sub-terminal is using the fourth configuration when sending the first data, it can know that the transmission mode of the first data has switched to non-local transmission mode.

According to the method of this embodiment, the terminal device (such as the first sub-terminal) can decide whether to switch the transmission mode of the first data based on certain conditions (such as the first condition/second condition), thereby increasing the decision-making power of the terminal device. In addition, the terminal device's autonomous determination of whether to switch the transmission mode of the first data based on certain conditions also reduces the process of reporting signaling to the head node to a certain extent.

Figure 12 is a schematic diagram of another possible implementation flow of the data transmission method provided in the embodiments of this application. As shown in Figure 12, this implementation flow may include the following steps:

S1201, the first sub-terminal and/or core network equipment sends a report to the head node.

In some embodiments, the report sent by the first sub-terminal to the head node may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the target terminal (denoted as the first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network device (denoted as the second PDB); the link signal quality from the first sub-terminal to the head node; and the link signal quality from the first sub-terminal to the target terminal.

In some embodiments, the report sent by the core network device to the head node may include, for example, a first data PDB transmitted from the core network device to the head node.

In some embodiments, S1201 may be omitted (not performed).

S1202, the head node determines whether the transmission mode of the first data needs to be switched to the target transmission mode.

In one implementation (referred to as implementation #21), the target transmission method is a non-local transmission method.

In another implementation (referred to as implementation #22), the target transmission method is the local transmission method.

For implementation #21, the head node can determine whether it is necessary to switch the transmission mode of the first data to the target transmission mode (non-local transmission mode) based on one or more of the following d1) to d7).

d1) The PDB of the first data.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the target terminal (first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment (second PDB); the PDB of the first data transmitted from the core network equipment to the head node; and the PDB of the first data transmitted from the head node to the target terminal.

In some embodiments, the first PDB and/or the second PDB may be sent to the head node by the first sub-terminal via a report in S1201.

In some embodiments, the first sub-terminal may send the first PDB and/or the second PDB to the head node if the first PDB and/or the second PDB are greater than or equal to the first threshold.

In some embodiments, when the first sub-terminal determines whether the first PDB and/or the second PDB are greater than or equal to the first threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data packet granularity.

In some embodiments, this determination process can be performed at the SDAP/PDCP/RLC/MAC layer.

In some embodiments, the first threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB configuration), or pre-configured, or defined by the protocol, or indicated by an upper layer.

In some embodiments, the configuration granularity of the first threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data priority level granularity; RSRP level granularity. In some embodiments, the first threshold can be configured uniformly, that is, without distinguishing granularity.

In some embodiments, the first data transmitted from the core network device to the head node's PDB can be sent to the head node by the core network device via a report in S1201.

d2) Link signal quality from the first sub-terminal to the head node.

In some embodiments, the link signal quality from the first sub-terminal to the head node can be reported by the first sub-terminal to the head node in S1201.

In some embodiments, the first sub-terminal may report the measurement result (i.e., the link signal quality from the first sub-terminal to the head node) to the head node when measurement reporting conditions are met (such as periodic reporting or event-based reporting). This measurement result can be a Layer 1 or Layer 3 measurement result. In some embodiments, the event may be configured by the head node. For example, the event may include: the measurement result is less than or equal to a second threshold. That is, if the measurement result is less than or equal to the second threshold, the first sub-terminal may report the measurement result to the head node.

In some embodiments, the second threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the second threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the second threshold can be configured uniformly, that is, without distinguishing granularity.

d3) Link signal quality from the first sub-terminal to the target terminal.

In some embodiments, the link signal quality from the first sub-terminal to the target terminal can be reported by the first sub-terminal to the head node in S1201.

In some embodiments, the first sub-terminal may report the measurement result (i.e., the link signal quality from the first sub-terminal to the target terminal) to the head node when measurement reporting conditions are met (such as periodic reporting or event-based reporting). This measurement result can be a Layer 1 or Layer 3 measurement result. In some embodiments, the event may be configured by the head node. For example, the event may include: the measurement result is less than or equal to a third threshold. That is, if the measurement result is less than or equal to the third threshold, the first sub-terminal may report the measurement result to the head node.

In some embodiments, the third threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the third threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the third threshold can be configured uniformly, that is, without distinguishing granularity.

d4) Link signal quality from the head node to the target terminal.

In some embodiments, the link signal quality from the head node to the target terminal can be reported by the target terminal to the head node.

In some embodiments, the target terminal may report the measurement result (i.e., the link signal quality from the head node to the target terminal) to the head node when the measurement reporting conditions are met (such as periodic reporting or event-based reporting). This measurement result can be a Layer 1 or Layer 3 measurement result. In some embodiments, the event can be configured by the head node. For example, the event may include: the measurement result is less than or equal to a fourth threshold. That is, if the measurement result is less than or equal to the fourth threshold, the target terminal may report the measurement result to the head node.

In some embodiments, the fourth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the fourth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the fourth threshold can be configured uniformly, that is, without distinguishing granularity.

d5) Whether the first sub-terminal and/or the target terminal experienced RLF, HO, RRC connection rebuild or BF.

For example, if the first sub-terminal and/or the target terminal experience RLF, HO, RRC connection reconstruction or BF, the head node can determine that the transmission mode of the first data needs to be switched to the target transmission mode (non-local transmission mode).

d6) The number of times the head node receives consecutive negative feedback from the first sub-terminal and/or the target terminal within a certain time period.

For example, if the head node receives consecutive PDCP/RLC/HARQ negations from the first sub-terminal and/or the target terminal within a certain time period. If feedback is received N times, it can be determined that the transmission mode of the first data needs to be switched to the target transmission mode (non-local transmission mode).

d7) Local transmission load of the head node.

For example, if the local transmission load of the head node is large, it can be determined that the transmission mode of the first data needs to be switched to the target transmission mode (non-local transmission mode).

For implementation #22, the head node can determine whether it is necessary to switch the transmission mode of the first data to the target transmission mode (local transmission mode) based on one or more of the following e1) to e7).

e1) The first data PDB.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the target terminal (first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment (second PDB); the PDB of the first data transmitted from the core network equipment to the head node; and the PDB of the first data transmitted from the head node to the target terminal.

In some embodiments, the first PDB and/or the second PDB may be sent to the head node by the first sub-terminal via a report in S1201.

In some embodiments, the first sub-terminal may send the first PDB and/or the second PDB to the head node if the first PDB and/or the second PDB are less than or equal to a fifth threshold.

In some embodiments, when the first sub-terminal determines whether the first PDB and/or the second PDB are less than or equal to the fifth threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data packet granularity.

In some embodiments, this determination process can be performed at the SDAP/PDCP/RLC/MAC layer.

In some embodiments, the fifth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB configuration), or pre-configured, or defined by the protocol, or indicated by an upper layer.

In some embodiments, the configuration granularity of the fifth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; data priority level granularity; RSRP level granularity. In some embodiments, the fifth threshold can be configured uniformly, that is, without distinguishing granularity.

e2) Link signal quality from the first sub-terminal to the head node.

In some embodiments, the link signal quality from the first sub-terminal to the head node can be reported by the first sub-terminal to the head node in S1201.

In some embodiments, the first sub-terminal may report the measurement result (i.e., the link signal quality from the first sub-terminal to the head node) to the head node when the measurement reporting conditions are met (such as periodic reporting or event-based reporting). This measurement result can be a Layer 1 or Layer 3 measurement result. In some embodiments, the event may be configured by the head node. For example, the event may include: the measurement result is greater than or equal to a sixth threshold. That is, if the measurement result is greater than or equal to the sixth threshold, the first sub-terminal may report the measurement result to the head node.

In some embodiments, the sixth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the sixth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the sixth threshold can be configured uniformly, that is, without distinguishing granularity.

e3) Link signal quality from the first sub-terminal to the target terminal.

In some embodiments, the link signal quality from the first sub-terminal to the target terminal can be reported by the first sub-terminal to the head node in S1201.

In some embodiments, the first sub-terminal may report the measurement result (i.e., the link signal quality from the first sub-terminal to the target terminal) to the head node when the measurement reporting conditions are met (such as periodic reporting or event-based reporting). This measurement result can be a Layer 1 or Layer 3 measurement result. In some embodiments, the event can be configured by the head node. For example, the event may include: the measurement result is greater than or equal to a seventh threshold. That is, if the measurement result is greater than or equal to the seventh threshold, the first sub-terminal may report the measurement result to the head node.

In some embodiments, the seventh threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the seventh threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the seventh threshold can be configured uniformly, that is, without distinguishing granularity.

e4) Link signal quality from the head node to the target terminal.

In some embodiments, the link signal quality from the head node to the target terminal can be reported by the target terminal to the head node.

In some embodiments, the target terminal may report the measurement result (i.e., the link signal quality from the head node to the target terminal) to the head node when the measurement reporting conditions are met (such as periodic reporting or event-based reporting). This measurement result can be a Layer 1 or Layer 3 measurement result. In some embodiments, the event can be configured by the head node. For example, the event may include: the measurement result is greater than or equal to an eighth threshold. That is, if the measurement result is greater than or equal to the eighth threshold, the target terminal may report the measurement result to the head node.

In some embodiments, the eighth threshold may be configured by the head node (e.g., via dedicated RRC signaling or SIB) or pre-configured.

In some embodiments, the configuration granularity of the eighth threshold can be one of the following: QoS flow granularity; bearer granularity; RLC channel granularity; logical channel granularity; service priority level granularity. In some embodiments, the eighth threshold can be configured uniformly, that is, without distinguishing granularity.

e5) Within a certain time period, the head node receives continuous positive feedback from the first sub-terminal and/or the target terminal via PDCP/RLC/HARQ. The number of times.

For example, if the head node receives N consecutive positive feedbacks of PDCP/RLC/HARQ from the first sub-terminal and/or the target terminal within a certain time period, it can be determined that the transmission mode of the first data needs to be switched to the target transmission mode (local transmission mode).

e6) Local transmission load of the head node.

For example, if the local transmission load of the head node is low, it can be determined that the transmission mode of the first data needs to be switched to the target transmission mode (local transmission mode).

S1203, the header node sends a second request/instruction message to the core network equipment.

If the head node determines that the transmission mode of the first data needs to be switched to the target transmission mode, it can send a second request/instruction message to the core network equipment. This second request/instruction message can be used to request/instruct the switching of the transmission mode of the first data to the target transmission mode.

In some embodiments, when the head node determines that the transmission mode of the first data needs to be switched to a non-local transmission mode, if a non-local path for the first data exists (i.e., a path used to transmit the first data from the head node to the core network device in the non-local transmission mode), the head node, after receiving the first data from the first sub-terminal, can send the first data to the core network device through this non-local path. In this case, the head node does not need to send the second request/indication information to the core network device, that is, it does not need to execute S1203. Correspondingly, if a non-local path for the first data does not exist, the head node needs to send the second request/indication information to the core network device.

S1204, the core network equipment sends third indication information and/or first configuration to the head node.

The third indication information can be used to instruct the transmission mode of the first data to be switched to the target transmission mode. The first configuration can be used by the head node to send (forward) the first data from the first sub-terminal using the target transmission mode.

For example, in implementation #21, the first configuration can be used to configure a non-local path for the first data, so that the head node can send (forward) the first data from the first sub-terminal using a non-local transmission method based on the first configuration.

For example, in implementation #22, the first configuration can be used to configure the local path for the first data, so that the head node can send (forward) the first data from the first sub-terminal using the local transmission method based on the first configuration.

S1205, the head node sends the fourth indication information and/or the second configuration to the first sub-terminal.

In this step, the head node may send a fourth indication message and/or a second configuration (reconfiguration message) to the first sub-terminal.

The fourth instruction information can be used to instruct the first data transmission mode to be switched to the target transmission mode. The second configuration can be used by the first sub-terminal to send the first data using the target transmission mode.

As an example, the fourth instruction information can be sent via RRC signaling, MAC CE, or DCI signaling; the second configuration can be sent via RRC signaling, for example.

In some embodiments, the header node may determine the second configuration based on the first configuration, or, if the core network device does not send the first configuration, the header node may determine the second configuration on its own.

In some embodiments, the second configuration may configure (or reconfigure) one or more of the following for the transmission of the first data:

Bearer configuration (reconfiguration);

RLC channel configuration (reconfiguration);

Logical channel configuration (reconfiguration);

CG resource configuration (reconfiguration);

Security configuration (reconfiguration) (such as key configuration/reconfiguration).

S1206, the first sub-terminal sends the first data using the target transmission method.

In this step, the first sub-terminal can send the first data using the target transmission method based on the second configuration.

It should be noted that in some embodiments, steps S1203 and S1204 can be omitted (not executed). That is, if the head node determines that the transmission mode of the first data needs to be switched to the target transmission mode, it may not need to send the second request/indication information to the core network device. Accordingly, the core network device may not need to send the third indication information and/or the first configuration to the head node.

In some embodiments, the head node can pre-configure for the terminal device a configuration for sending the first data in a local transmission mode (denoted as the third configuration) and a configuration for sending the first data in a non-local transmission mode (denoted as the fourth configuration). Thus, when the head node determines that the transmission mode of the first data needs to be switched to the target transmission mode, it can indicate the information of the first data (i.e., the data to be switched) to the first sub-terminal via MAC CE or DCI information. For example, it can indicate the ID corresponding to the first data (such as QoS flow ID/bearer ID/logical channel (LCH) ID/connection ID, etc.). Upon receiving this indication, the first sub-terminal can then send the first data using the configuration corresponding to the other transmission mode (i.e., the target transmission mode).

According to the method of this embodiment, since local transmission is performed by the head node for data forwarding, the head node, as an intermediate node, can know the status of the two links (the link between the first sub-terminal and the head node, and the link between the head node and the target terminal), and has better control over AS configuration/resources. Therefore, having the head node determine whether to switch the data transmission mode is beneficial to ensuring the overall stability of the communication system.

Figure 13 is a schematic diagram of another possible implementation flow of the data transmission method provided in the embodiments of this application. As shown in Figure 13, this implementation flow may include the following steps:

S1301, the first sub-terminal and/or head node sends a report to the core network equipment.

In some embodiments, the report sent by the first sub-terminal to the core network device may include one or more of the following: a PDB of first data transmitted from the first sub-terminal to the target terminal (denoted as the first PDB); and a PDB of first data transmitted from the first sub-terminal to the core network device (denoted as the second PDB).

In some embodiments, the report sent by the head node to the core network device may include: a first data PDB transmitted from the head node to the target terminal.

In some embodiments, S1301 may be omitted (not executed).

S1302, the core network equipment determines whether it is necessary to switch the transmission mode of the first data to the target transmission mode.

In one implementation (referred to as implementation #31), the target transmission method is a non-local transmission method.

In another implementation (referred to as implementation #32), the target transmission method is the local transmission method.

In some embodiments, the head node may determine whether it is necessary to switch the transmission mode of the first data to the target transmission mode based on one or more of the following f1) to f3).

f1) The PDB of the first data.

As an example, the PDB of the first data may include one or more of the following: the PDB of the first data transmitted from the first sub-terminal to the target terminal (first PDB); the PDB of the first data transmitted from the first sub-terminal to the core network equipment (second PDB); the PDB of the first data transmitted from the core network equipment to the head node; and the PDB of the first data transmitted from the head node to the target terminal.

In some embodiments, the first PDB and/or the second PDB may be sent to the core network equipment by the first sub-terminal via a report in S1301.

In some embodiments, for implementation #31, the first sub-terminal may send the first PDB and/or the second PDB to the head node if the first PDB and/or the second PDB are greater than or equal to the first threshold.

In some embodiments, for implementation #32, the first sub-terminal may send the first PDB and/or the second PDB to the head node if the first PDB and/or the second PDB are less than or equal to the second threshold.

In some embodiments, when the first sub-terminal determines whether the first PDB and/or the second PDB is greater than or equal to the first threshold, and/or when it determines whether the first PDB and/or the second PDB is less than or equal to the second threshold, the granularity of the determination (i.e., the granularity of the first data) can be one of the following: QoS flow granularity; packet granularity; PDU session granularity.

In some embodiments, the first data transmitted from the head node to the PDB of the target terminal can be sent by the head node to the core network device via a report in S1301.

f2) Whether the first sub-terminal and/or the target terminal has an HO.

For example, if the first sub-terminal and/or the target terminal experiences a HO (Ho) event, the core network equipment can determine that the transmission mode of the first data needs to be switched to a non-local transmission mode.

f3) Load status of core network equipment.

For example, if the core network equipment is under heavy load, it can be determined that the transmission mode of the first data needs to be switched to the local transmission mode.

For example, if the load on the core network equipment is low, it can be determined that the transmission mode of the first data needs to be switched to a non-local transmission mode.

S1303, the core network device sends the first indication information and/or the first configuration to the head node.

The first indication information can be used to indicate that the transmission mode of the first data be switched to the target transmission mode. The first configuration can be used by the head node to send (forward) the first data from the first sub-terminal using the target transmission mode.

For example, if the core network equipment determines that the transmission mode of the first data needs to be switched to a non-local transmission mode, the first configuration can be used to configure the non-local path of the first data. Thus, the head node can send (forward) the first data from the first sub-terminal using the non-local transmission mode based on the first configuration.

For example, when the core network equipment determines that the transmission mode of the first data needs to be switched to the local transmission mode, the first configuration can be used to configure the local path of the first data. Thus, the head node can send (forward) the first data from the first sub-terminal using the local transmission mode based on the first configuration.

S1304, the head node sends the second indication information and/or the second configuration to the first sub-terminal.

In this step, the head node may send second indication information and/or second configuration (reconfiguration information) to the first sub-terminal.

The second indication information can be used to instruct the first data transmission mode to be switched to the target transmission mode. The second configuration can be used by the first sub-terminal to send the first data using the target transmission mode. The second configuration can be determined based on the first configuration, or it can be determined by the head node itself.

As an example, the second indication information may be sent via RRC signaling, MAC CE, or DCI signaling; the second configuration may be sent via RRC signaling.

In some embodiments, the second configuration may configure (or reconfigure) one or more of the following for the transmission of the first data:

Bearer configuration (reconfiguration);

RLC channel configuration (reconfiguration);

Logical channel configuration (reconfiguration);

CG resource configuration (reconfiguration);

Security configuration (reconfiguration) (such as key configuration/reconfiguration).

S1305, the first sub-terminal sends the first data using the target transmission method.

In this step, the first sub-terminal can send the first data using the target transmission method based on the second configuration.

In some embodiments, the head node can pre-configure for the terminal device a configuration for sending the first data in a local transmission mode (denoted as the third configuration) and a configuration for sending the first data in a non-local transmission mode (denoted as the fourth configuration). Thus, when the core network device determines that it needs to switch the transmission mode of the first data to the target transmission mode, it can indicate the information of the first data (i.e., the data to be switched) to the head node, which then indicates the information of the first data to the first sub-terminal via MAC CE or DCI information. For example, it can indicate the ID corresponding to the first data (such as QoS flow ID/bearer ID/LCH ID/connection ID, etc.). Upon receiving this indication, the first sub-terminal can then send the first data using the configuration corresponding to the other transmission mode (i.e., the target transmission mode).

According to the method of this embodiment, since data not passing through the core network may cause some concerns among all parties regarding data security and traffic billing, the core network equipment can determine whether to switch the data transmission mode, which can alleviate the above concerns to a certain extent.

Currently, support for local services requires the participation of the core network, meaning routing and forwarding must be performed at the UPF level. This makes it impossible to meet the requirements of lower latency, massive connectivity, and flexible deployment in 6G. Therefore, this application's embodiments consider local service processing based on Radio Access Network (RAN) nodes (base stations). Furthermore, considering the participation of RAN nodes in local service processing, this application's embodiments provide a scheme for switching data transmission methods, thereby enabling flexible control over the transmission latency of the first data.

In the embodiments of this application, terminal devices (such as the first sub-terminal), head nodes (such as base stations), and core network devices are considered as the triggers for data transmission mode switching, and the triggering conditions and corresponding signaling interaction processes under each triggering mode are considered. Specifically, the terminal device-triggered switching scheme further enhances the decision-making role of the terminal device in the network and improves its flexibility; the head node-triggered switching scheme can adjust the transmission scheme in a timely manner according to the AS status within the network, allowing services to be processed differently under different conditions to achieve the best performance; and the core network device-triggered switching scheme can enhance the core network's control over services.

It should be noted that in some scenarios, the above method can be implemented on the header node based on the subnet networking concept. In this case, all child UEs associated with the header node can constitute a local service group. That is, the header node can be the header node in a subnet. In this case, the first child terminal and the target terminal (second child terminal) can be two child terminal devices associated with the header node, wherein the header node, the first child terminal, and the target terminal belong to the same subnet, and the first child terminal and the target terminal can constitute a local service group.

In some scenarios, the above methods can be implemented without being based on the subnetwork networking concept, but rather applied to general base stations (gNBs). In other words, the head node mentioned above can be a general base station. In this case, pairing relationships/group relationships (such as the group relationship of a local service group) can be maintained by the network.

The preferred embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solutions of this application, and these simple modifications all fall within the protection scope of this application. For example, the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this application will not describe the various possible combinations separately. Furthermore, various different embodiments of this application can also be arbitrarily combined, as long as they do not violate the spirit of this application, they should also be considered as the content disclosed in this application. Moreover, without conflict, the various embodiments and/or the technical features in the various embodiments described in this application can be arbitrarily combined with the prior art, and the resulting technical solutions should also fall within the protection scope of this application.

It should also be understood that in the various method embodiments of this application, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. Furthermore, in the embodiments of this application, the terms "downlink," "uplink," and "sidelink" are used to indicate the transmission direction of signals or data. "Downlink" indicates that the transmission direction of signals or data is a first direction from the site to the user equipment in the cell; "uplink" indicates that the transmission direction of signals or data is a second direction from the user equipment in the cell to the site; and "sidelink" indicates that the transmission direction of signals or data is a third direction from user equipment 1 to user equipment 2. For example, "downlink signal" indicates that the transmission direction of the signal is the first direction. Additionally, in the embodiments of this application, the term "and/or" is merely a description of the association relationship between related objects, indicating that three relationships can exist. Specifically, A and/or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, the character "/" in this document generally indicates that the preceding and following related objects have an "or" relationship.

Based on the foregoing embodiments, this application provides a corresponding data transmission device.

Figure 14 is a schematic diagram of the structure of a data transmission device provided in an embodiment of this application, applied to a first sub-terminal. As shown in Figure 14, the data transmission device 1400 (hereinafter referred to as device 1400) includes:

The first communication unit 1401 is configured to send first information to the head node. The first information is used to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The first data is sent by the device 1400 and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In some embodiments, the target transmission mode is the second transmission mode. When the transmission mode of the first data is the second transmission mode, the first data is sent to the second sub-terminal through the head node and the core network device.

In some embodiments, the first communication unit 1401 is further configured to: send the first information to the head node when a first condition is met, the first condition including one or more of the following: the upper layer of the device 1400 instructs to switch the transmission mode of the first data to the target transmission mode; the packet delay budget (PDB) of the first data is greater than or equal to a first threshold; the link signal quality between the device 1400 and the head node is less than or equal to a second threshold; the link signal quality between the head node and the second sub-terminal is less than or equal to a third threshold; the link signal quality between the device 1400 and the second sub-terminal is less than or equal to a fourth threshold; within a first duration, a first number of negative feedbacks are continuously received from the head node and/or the second sub-terminal, and the first number is greater than or equal to a fifth threshold; a first event occurs in the device 1400; a first event occurs in the second sub-terminal; wherein the first event includes one of the following: Radio Link Failure (RLF), Handover (HO), Radio Resource Control (RRC) Connection Re-establishment, and Beam Failure (BF).

In some embodiments, the target transmission method is the first transmission method.

In some embodiments, the first communication unit 1401 is further configured to: send the first information to the head node when a second condition is met, the second condition including one or more of the following: the upper layer of the device 1400 instructs to switch the transmission mode of the first data to the target transmission mode; the PDB of the first data is less than or equal to a sixth threshold; the link signal quality between the device 1400 and the head node is greater than or equal to a seventh threshold; the link signal quality between the head node and the second sub-terminal is greater than or equal to an eighth threshold; the link signal quality between the device 1400 and the second sub-terminal is greater than or equal to a ninth threshold; and within a first duration, a first number of positive feedbacks are continuously received from the head node and/or the device 1400, and the first number is greater than or equal to a tenth threshold.

In some embodiments, the first communication unit 1401 is further configured to: receive second information from the head node before sending the first information to the head node, the second information being used to indicate the link signal quality between the head node and the second sub-terminal.

In some embodiments, the first communication unit 1401 is further configured to receive third information from the head node, the third information being used to indicate switching the transmission mode of the first data to the target transmission mode.

In some embodiments, the first communication unit 1401 is further configured to receive a first configuration from the head node, the first configuration being used by the device 1400 to send the first data using the target transmission method.

In some embodiments, the first configuration includes one or more of the following: bearer configuration; radio link control channel configuration; logical channel configuration; configuration of authorized resources; and security configuration.

In some embodiments, the first information includes one or more of the following: information about the first data; the reason for the switching; the link signal quality between the device 1400 and the head node; and the link signal quality between the device 1400 and the second sub-terminal.

In some embodiments, the first information is the first data, the configuration used by the device 1400 when sending the first data, and/or the header information of the first data, used to request or indicate that the transmission mode of the first data be switched to the target transmission mode.

In some embodiments, the first communication unit 1401 is further configured to: receive a second configuration and a third configuration from the head node before sending the first information to the head node; the second configuration is used by the device 1400 to send the first data using the first transmission method; the third configuration is used by the device 1400 to send the first data using the second transmission method.

In some embodiments, the granularity of the first data is one of the following: service flow granularity; quality of service flow granularity; bearer granularity; data packet granularity; radio link control channel granularity; logical channel granularity; service type granularity; service granularity; protocol data unit session granularity; connection granularity.

Figure 15 is a schematic diagram of the structure of the data transmission device provided in this embodiment of the application, applied to the head node. As shown in Figure 1500, the data transmission device 1500 (hereinafter referred to as device 1500) includes:

The second communication unit 1501 is configured to receive first information from the first sub-terminal. The first information is used to request or indicate that the transmission mode of the first data be switched to a target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the device 1500.

In some embodiments, the target transmission mode is the second transmission mode. When the transmission mode of the first data is the second transmission mode, the first data is sent to the second sub-terminal through the device 1500 and the core network equipment.

In some embodiments, the target transmission method is the first transmission method.

In some embodiments, the second communication unit 1501 is further configured to send second information to the first sub-terminal before receiving the first information from the first sub-terminal, the second information being used to indicate the link signal quality between the device 1500 and the second sub-terminal.

In some embodiments, the second communication unit 1501 is further configured to send fourth information to the core network device, the fourth information being used to request or indicate that the transmission mode of the first data be switched to the target transmission mode.

In some embodiments, the second communication unit 1501 is further configured to: receive fifth information and/or fourth configuration from the core network device; the fifth information is used to indicate switching the transmission mode of the first data to the target transmission mode; the fourth configuration is used by the device 1500 to send the first data from the first sub-terminal using the target transmission mode.

In some embodiments, the second communication unit 1501 is further configured to send a first configuration to the first sub-terminal, the first configuration being used by the first sub-terminal to send the first data using the target transmission method, the first configuration being related to the fourth configuration.

In some embodiments, the second communication unit 1501 is further configured to send a first configuration to the first sub-terminal, the first configuration being used by the first sub-terminal to send the first data using the target transmission method.

In some embodiments, the first configuration includes one or more of the following: bearer configuration; radio link control channel configuration; logical channel configuration; configuration of authorized resources; and security configuration.

In some embodiments, the second communication unit 1501 is further configured to send third information to the first sub-terminal, the third information being used to indicate that the transmission mode of the first data be switched to the target transmission mode.

In some embodiments, the first information includes one or more of the following: information about the first data; the reason for the switching; the link signal quality between the first sub-terminal and the device 1500; and the link signal quality between the first sub-terminal and the second sub-terminal.

In some embodiments, the first information is the first data, the configuration used by the first sub-terminal when sending the first data, and/or the header information of the first data, used to request or indicate that the transmission mode of the first data be switched to the target transmission mode.

In some embodiments, the second communication unit 1501 is further configured to: send a second configuration and a third configuration to the first sub-terminal before receiving the first information from the first sub-terminal; the second configuration is used for the first sub-terminal to send the first data using the first transmission method; the third configuration is used for the first sub-terminal to send the first data using the second transmission method.

In some embodiments, the first information is the first data, and the second communication unit 1501 is further configured to send the first data to the core network device.

In some embodiments, the granularity of the first data is one of the following: service flow granularity; quality of service flow granularity; bearer granularity; data packet granularity; radio link control channel granularity; logical channel granularity; service type granularity; service granularity; protocol data unit session granularity; connection granularity.

Figure 16 is a schematic diagram of the structure of the data transmission device provided in this application embodiment, applied to the head node. As shown in Figure 16, the data transmission device 1600 (hereinafter referred to as device 1600) includes:

The third communication unit 1601 is configured to send first information to the first sub-terminal. The first information is used to instruct the transmission mode of the first data to be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the device 1600.

In some embodiments, the target transmission method is the second transmission method. When the transmission method of the first data is the second transmission method, the first data is sent to the second sub-terminal through the device 1600 and the core network equipment.

In some embodiments, the device 1600 further includes: a processing unit configured to determine, before sending the first information to the first sub-terminal, whether to switch the transmission mode of the first data to the target transmission mode based on one or more of the following: packet delay budget (PDB) of the first data; link signal quality between the first sub-terminal and the device 1600; link signal quality between the device 1600 and the second sub-terminal; link signal quality between the first sub-terminal and the second sub-terminal; the number of consecutive negative feedbacks received from the first sub-terminal and/or the second sub-terminal within a first duration; the load status of the device 1600; whether a first event has occurred at the first sub-terminal; whether a first event has occurred at the second sub-terminal; wherein the first event includes one of the following: radio link failure (RLF), handover (HO), radio resource control (RRC) connection re-establishment, and beam failure (BF).

In some embodiments, the third communication unit 1601 is further configured to send the first data from the first sub-terminal to the core network device.

In some embodiments, the target transmission method is the first transmission method.

In some embodiments, the device 1600 further includes: a processing unit configured to determine, before sending the first information to the first sub-terminal, whether to switch the transmission mode of the first data to the target transmission mode based on one or more of the following: the PDB of the first data; the link signal quality between the first sub-terminal and the device 1600; the link signal quality between the device 1600 and the second sub-terminal; the link signal quality between the first sub-terminal and the second sub-terminal; the number of consecutive positive feedbacks received from the first sub-terminal and/or the second sub-terminal within a first duration; and the load status of the device 1600.

In some embodiments, the third communication unit 1601 is further configured to receive one or more of the following information before sending the first information to the first sub-terminal: the PDB of the first data; the link signal quality between the first sub-terminal and the device 1600; the link signal quality between the device 1600 and the second sub-terminal; and the link signal quality between the first sub-terminal and the second sub-terminal.

In some embodiments, the third communication unit 1601 is further configured to send second information to the core network device before sending the first information to the first sub-terminal, the second information being used to request or indicate that the transmission mode of the first data be switched to the target transmission mode.

In some embodiments, the third communication unit 1601 is further configured to: receive third information and/or a first configuration from the core network device; the third information is used to indicate switching the transmission mode of the first data to the target transmission mode; the first configuration is used for The device 1600 uses the target transmission method to send the first data from the first sub-terminal.

In some embodiments, the third communication unit 1601 is further configured to send a second configuration to the first sub-terminal, the second configuration being used by the first sub-terminal to send the first data using the target transmission method, the second configuration being related to the first configuration.

In some embodiments, the third communication unit 1601 is further configured to send a second configuration to the first sub-terminal, the second configuration being used by the first sub-terminal to send the first data using the target transmission method.

In some embodiments, the second configuration includes one or more of the following: bearer configuration; radio link control channel configuration; logical channel configuration; configuration of authorized resources; and security configuration.

In some embodiments, the third communication unit 1601 is further configured to: send a third configuration and a fourth configuration to the first sub-terminal before sending the first information to the first sub-terminal; the third configuration is used for the first sub-terminal to send the first data using the first transmission method; the fourth configuration is used for the first sub-terminal to send the first data using the second transmission method.

In some embodiments, the first information includes: information about the first data.

In some embodiments, the third communication unit 1601 is further configured to receive the first data from the first sub-terminal, wherein the transmission mode of the first data is the target transmission mode.

In some embodiments, the granularity of the first data is one of the following: service flow granularity; quality of service flow granularity; bearer granularity; data packet granularity; radio link control channel granularity; logical channel granularity; service type granularity; service granularity; protocol data unit session granularity; connection granularity.

Figure 17 is a schematic diagram of the structure of the data transmission device provided in this application embodiment, applied to a first sub-terminal. As shown in Figure 17, the data transmission device 1700 (hereinafter referred to as device 1700) includes:

The fourth communication unit 1701 is configured to receive first information from the head node. The first information is used to indicate that the transmission mode of the first data is switched to the target transmission mode. The first data is sent by the device 1700 and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In some embodiments, the target transmission mode is the second transmission mode. When the transmission mode of the first data is the second transmission mode, the first data is sent to the second sub-terminal through the head node and the core network device.

In some embodiments, the target transmission method is the first transmission method.

In some embodiments, the fourth communication unit 1701 is further configured to: send the packet delay budget (PDB) of the first data to the head node before receiving the first information from the head node; or, send the PDB of the first data to the head node if a first condition is met.

In some embodiments, the fourth communication unit 1701 is further configured to: send a measurement result to the head node before receiving the first information from the head node; or, send the measurement result to the head node when a second condition is met; wherein the measurement result includes: the link signal quality between the device 1700 and the head node, and/or, the link signal quality between the device 1700 and the second sub-terminal.

In some embodiments, the fourth communication unit 1701 is further configured to receive a second configuration from the head node, the second configuration being used by the device 1700 to send the first data using the target transmission method.

In some embodiments, the second configuration includes one or more of the following: bearer configuration; radio link control channel configuration; logical channel configuration; configuration of authorized resources; and security configuration.

In some embodiments, the fourth communication unit 1701 is further configured to: receive a third configuration and a fourth configuration from the head node before receiving the first information from the head node; the third configuration is used by the device 1700 to send the first data using the first transmission method; and the fourth configuration is used by the device 1700 to send the first data using the second transmission method.

In some embodiments, the first information includes: information about the first data.

In some embodiments, the fourth communication unit 1701 is further configured to send the first data to the head node using the target transmission method.

In some embodiments, the granularity of the first data is one of the following: service flow granularity; quality of service flow granularity; bearer granularity; data packet granularity; radio link control channel granularity; logical channel granularity; service type granularity; service granularity; protocol data unit session granularity; connection granularity.

Figure 18 is a schematic diagram of the structure of the data transmission device provided in this embodiment of the application, which is applied to core network equipment. As shown in Figure 18, the data transmission device 1800 (hereinafter referred to as device 1800) includes:

The fifth communication unit 1801 is configured to send first information to the head node. The first information is used to indicate that the transmission mode of the first data is switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the head node.

In some embodiments, the target transmission method is the second transmission method, and the transmission method of the first data is the second transmission method. In the transmission mode, the first data is sent to the second sub-terminal through the header node and device 1800.

In some embodiments, the target transmission method is the first transmission method.

In some embodiments, the apparatus 1800 further includes a processing unit configured to determine, before sending the first information to the head node, whether to switch the transmission mode of the first data to the target transmission mode based on one or more of the following: the packet delay budget (PDB) of the first data; whether the first sub-terminal has been switched; whether the second sub-terminal has been switched; and the load status of the apparatus 1800.

In some embodiments, the fifth communication unit 1801 is further configured to receive the PDB of the first data before sending the first information to the head node.

In some embodiments, the fifth communication unit 1801 is further configured to send a first configuration to the head node, the first configuration being used by the head node to send the first data from the first sub-terminal using the target transmission method.

In some embodiments, the first information includes: information about the first data.

In some embodiments, the granularity of the first data is one of the following: service flow granularity; quality of service flow granularity; bearer granularity; data packet granularity; radio link control channel granularity; logical channel granularity; service type granularity; service granularity; protocol data unit session granularity; connection granularity.

Figure 19 is a schematic diagram of the structure of the data transmission device provided in an embodiment of this application. Applied to the head node, as shown in Figure 19, the data transmission device 1900 (hereinafter referred to as device 1900) includes:

The sixth communication unit 1901 is configured to receive first information from the core network device. The first information is used to instruct the transmission mode of the first data to be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission mode is either the first transmission mode or the second transmission mode. When the transmission mode of the first data is the first transmission mode, the first data is sent to the second sub-terminal through the device.

In some embodiments, the target transmission mode is the second transmission mode. When the transmission mode of the first data is the second transmission mode, the first data is sent to the second sub-terminal through the device 1900 and the core network device.

In some embodiments, the target transmission method is the first transmission method.

In some embodiments, the sixth communication unit 1901 is further configured to send the PDB of the first data to the core network device before receiving the first information from the core network device.

In some embodiments, the sixth communication unit 1901 is further configured to receive a first configuration from the core network device, the first configuration being used by the device 1900 to send the first data from the first sub-terminal using the target transmission method.

In some embodiments, the sixth communication unit 1901 is further configured to send a second configuration to the first sub-terminal, the second configuration being used by the first sub-terminal to send the first data using the target transmission method, the second configuration being related to the first configuration.

In some embodiments, the sixth communication unit 1901 is further configured to send a second configuration to the first sub-terminal, the second configuration being used by the first sub-terminal to send the first data using the target transmission method.

In some embodiments, the second configuration includes one or more of the following: bearer configuration; radio link control channel configuration; logical channel configuration; configuration of authorized resources; and security configuration.

In some embodiments, the sixth communication unit 1901 is further configured to: send a third configuration and a fourth configuration to the first sub-terminal before receiving the first information from the core network device; the third configuration is used for the first sub-terminal to send the first data using the first transmission method; the fourth configuration is used for the first sub-terminal to send the first data using the second transmission method.

In some embodiments, the sixth communication unit 1901 is further configured to send second information to the first sub-terminal, the second information being used to instruct the transmission mode of the first data to be switched to the target transmission mode.

In some embodiments, the second information includes information about the first data.

In some embodiments, the first information includes: information about the first data.

In some embodiments, the granularity of the first data is one of the following: service flow granularity; quality of service flow granularity; bearer granularity; data packet granularity; radio link control channel granularity; logical channel granularity; service type granularity; service granularity; protocol data unit session granularity; connection granularity.

Those skilled in the art should understand that the description of the data transmission device in the embodiments of this application can be understood with reference to the description of the data transmission method in the embodiments of this application.

Figure 20 is a schematic structural diagram of a communication device provided in an embodiment of this application. This communication device may be a first sub-terminal, a head node, or a core network device. The communication device 2000 shown in Figure 20 includes a processor 2010, which can call and run computer programs from memory to implement the methods in the embodiments of this application.

Optionally, as shown in FIG20, the communication device 2000 may further include a memory 2020. The processor 2010 may retrieve and run computer programs from the memory 2020 to implement the methods in the embodiments of this application.

The memory 2020 can be a separate device independent of the processor 2010, or it can be integrated into the processor 2010.

Optionally, as shown in FIG20, the communication device 2000 may further include a transceiver 2030, and the processor 2010 may control the transceiver 2030 to communicate with other devices. Specifically, it may send information or data to other devices or receive information or data sent by other devices.

The transceiver 2030 may include a transmitter and a receiver. The transceiver 2030 may further include an antenna, and the number of antennas may be one or more.

Optionally, the communication device 2000 may specifically be the first sub-terminal in the embodiments of this application, and the communication device 2000 may implement the corresponding processes implemented by the first sub-terminal in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the communication device 2000 may specifically be the head node of the embodiments of this application, and the communication device 2000 may implement the corresponding processes implemented by the head node in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the communication device 2000 may specifically be the core network device in the embodiments of this application, and the communication device 2000 may implement the corresponding processes implemented by the core network device in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Figure 21 is a schematic structural diagram of a chip according to an embodiment of this application. The chip 2100 shown in Figure 21 includes a processor 2110, which can call and run computer programs from memory to implement the methods in the embodiments of this application.

Optionally, as shown in FIG21, chip 2100 may further include memory 2120. Processor 2110 may retrieve and run computer programs from memory 2120 to implement the methods in the embodiments of this application.

The memory 2120 can be a separate device independent of the processor 2110, or it can be integrated into the processor 2110.

Optionally, the chip 2100 may also include an input interface 2130. The processor 2110 can control the input interface 2130 to communicate with other devices or chips; specifically, it can acquire information or data sent by other devices or chips.

Optionally, the chip 2100 may also include an output interface 2140. The processor 2110 can control the output interface 2140 to communicate with other devices or chips, specifically, to output information or data to other devices or chips.

Optionally, the chip can be applied to the first sub-terminal in the embodiments of this application, and the chip can implement the corresponding processes implemented by the first sub-terminal in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the chip can be applied to the head node in the embodiments of this application, and the chip can implement the corresponding processes implemented by the head node in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

This application also provides a computer storage medium storing one or more programs, which can be executed by one or more processors to implement the methods in this application.

Figure 22 is a schematic block diagram of a communication system 2200 provided in an embodiment of this application. As shown in Figure 22, the communication system 2200 includes a first sub-terminal 2210, a head node 2220, and a core network device 2230.

The first sub-terminal 2210 can be used to implement the corresponding functions implemented by the first sub-terminal in the above method, the head node 2220 can be used to implement the corresponding functions implemented by the head node in the above method, and the core network device 2230 can be used to implement the corresponding functions implemented by the core network device in the above method. For the sake of brevity, these will not be elaborated further here.

It should be understood that the processor in the embodiments of this application may be an integrated circuit chip with signal processing capabilities. In implementation, the steps of the above method embodiments can be completed by integrated logic circuits in the processor's hardware or by instructions in software form. The processor described above may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in the memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps of the above method.

It is understood that the memory in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDR SDRAM), Enhanced Synchronous DRAM (ESDRAM), Synchlink DRAM (SLDRAM), and Direct Rambus RAM (DR RAM). It should be noted that the memory used in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

It should be understood that the above-described memory is exemplary but not restrictive. For example, the memory in the embodiments of this application may also be static random access memory (SRAM), dynamic random access memory (DRAM), or synchronous dynamic random access memory. Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced synchronous SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct memory bus RAM (DR RAM), etc. In other words, the memory in the embodiments of this application is intended to include, but is not limited to, these and any other suitable types of memory.

This application also provides a computer-readable storage medium for storing computer programs.

Optionally, the computer-readable storage medium can be applied to the first sub-terminal in the embodiments of this application, and the computer program causes the computer to execute the corresponding processes implemented by the first sub-terminal in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the computer-readable storage medium can be applied to the head node in the embodiments of this application, and the computer program causes the computer to execute the corresponding processes implemented by the head node in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the computer-readable storage medium can be applied to the core network device in the embodiments of this application, and the computer program causes the computer to execute the corresponding processes implemented by the core network device in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

This application also provides a computer program product, including computer program instructions.

Optionally, the computer program product can be applied to the first sub-terminal in the embodiments of this application, and the computer program instructions cause the computer to execute the corresponding processes implemented by the first sub-terminal in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the computer program product can be applied to the head node in the embodiments of this application, and the computer program instructions cause the computer to execute the corresponding processes implemented by the head node in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the computer program product can be applied to the core network device in the embodiments of this application, and the computer program instructions cause the computer to execute the corresponding processes implemented by the core network device in the various methods of the embodiments of this application. For the sake of brevity, they will not be described in detail here.

This application also provides a computer program.

Optionally, the computer program can be applied to the first sub-terminal in the embodiments of this application. When the computer program is run on the computer, it causes the computer to execute the corresponding processes implemented by the first sub-terminal in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the computer program can be applied to the head node in the embodiments of this application. When the computer program is run on a computer, it causes the computer to execute the corresponding processes implemented by the head node in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

Optionally, the computer program can be applied to the core network device in the embodiments of this application. When the computer program is run on a computer, it causes the computer to execute the corresponding processes implemented by the core network device in the various methods of the embodiments of this application. For the sake of brevity, it will not be described in detail here.

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

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

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

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

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

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

The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims (85)

A data transmission method, applied to a first sub-terminal, the method comprising: Send first information to the head node. The first information is used to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. According to the method of claim 1, wherein, The target transmission mode is the second transmission mode. When the transmission mode of the first data is the second transmission mode, the first data is sent to the second sub-terminal through the head node and the core network device. According to the method of claim 2, wherein sending the first information to the head node includes: If a first condition is met, the first information is sent to the head node, wherein the first condition includes one or more of the following: The upper layer of the first sub-terminal instructs the transmission mode of the first data to be switched to the target transmission mode; The packet delay budget (PDB) of the first data is greater than or equal to the first threshold. The link signal quality between the first sub-terminal and the head node is less than or equal to the second threshold. The link signal quality between the head node and the second sub-terminal is less than or equal to a third threshold. The link signal quality between the first sub-terminal and the second sub-terminal is less than or equal to the fourth threshold. Within a first time period, a first number of negative feedbacks are continuously received from the head node and/or the second sub-terminal, and the first number is greater than or equal to a fifth threshold. The first event occurs in the first sub-terminal; The second sub-terminal experiences the first event; The first event includes one of the following: Radio Link Failure (RLF), Handover (HO), Radio Resource Control (RRC) Connection Re-establishment, and Beam Failure (BF). According to the method of claim 1, wherein, The target transmission method is the first transmission method. According to the method of claim 4, wherein sending the first information to the head node includes: If the second condition is met, the first information is sent to the head node, where the second condition includes one or more of the following: The upper layer of the first sub-terminal instructs the transmission mode of the first data to be switched to the target transmission mode; The PDB of the first data is less than or equal to the sixth threshold; The link signal quality between the first sub-terminal and the head node is greater than or equal to the seventh threshold. The link signal quality between the head node and the second sub-terminal is greater than or equal to the eighth threshold. The link signal quality between the first sub-terminal and the second sub-terminal is greater than or equal to the ninth threshold. Within a first time period, a first number of positive feedbacks are continuously received from the head node and/or the first sub-terminal, and the first number is greater than or equal to the tenth threshold. The method according to any one of claims 1 to 5, wherein, before sending the first information to the head node, the method further comprises: Receive second information from the head node, the second information being used to indicate the link signal quality between the head node and the second sub-terminal. The method according to any one of claims 1 to 6, wherein the method further comprises: Receive third information from the head node, the third information being used to indicate switching the transmission mode of the first data to the target transmission mode. The method according to any one of claims 1 to 7, wherein the method further comprises: Receive a first configuration from the head node, the first configuration being used by the first sub-terminal to send the first data using the target transmission method. The method according to claim 8, wherein, The first configuration includes one or more of the following: Bearer configuration; Wireless link control channel configuration; Logical channel configuration; Configure authorized resources; Security configuration. The method according to any one of claims 1 to 9, wherein, The first information includes one or more of the following: Information from the first data; Reason for switching; The link signal quality between the first sub-terminal and the head node; The link signal quality between the first sub-terminal and the second sub-terminal. The method according to any one of claims 1 to 6, wherein, The first information is the first data, the configuration used by the first sub-terminal when sending the first data, and/or the header information of the first data, used to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The method according to claim 11, wherein, before sending the first information to the head node, the method further comprises: Receive the second and third configurations from the head node; The second configuration is used for the first sub-terminal to send the first data using the first transmission method; The third configuration is used by the first sub-terminal to send the first data using the second transmission method. The method according to any one of claims 1 to 12, wherein, The granularity of the first data is one of the following: Service flow granularity; Service quality flow granularity; Bearing particle size; Data packet granularity; Wireless link control channel granularity; Logical channel granularity; Service type granularity; Service granularity; Protocol data unit session granularity; Connection granularity. A data transmission method applied to a head node, the method comprising: Receive first information from the first sub-terminal, the first information being used to request or instruct switching the transmission mode of the first data to the target transmission mode, the first data being sent by the first sub-terminal and received by the second sub-terminal; The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. The method according to claim 14, wherein, The target transmission mode is the second transmission mode. When the transmission mode of the first data is the second transmission mode, the first data is sent to the second sub-terminal through the head node and the core network equipment. The method according to claim 14, wherein, The target transmission method is the first transmission method. The method according to any one of claims 14 to 16, wherein, before receiving the first information from the first sub-terminal, the method further comprises: Send a second message to the first sub-terminal, the second message being used to indicate the link signal quality between the head node and the second sub-terminal. The method according to any one of claims 14 to 17, wherein the method further comprises: Send a fourth message to the core network equipment, the fourth message being used to request or instruct the transmission mode of the first data to be switched to the target transmission mode. The method according to claim 18, wherein the method further comprises: Receive fifth information and/or fourth configuration from the core network device; The fifth piece of information is used to indicate that the transmission mode of the first data be switched to the target transmission mode; the fourth configuration is used by the head node to send the first data from the first sub-terminal using the target transmission mode. The method according to claim 19, wherein the method further comprises: Send a first configuration to the first sub-terminal. The first configuration is used by the first sub-terminal to send the first data using the target transmission method. The first configuration is related to the fourth configuration. The method according to any one of claims 14 to 20, wherein the method further comprises: Send a first configuration to the first sub-terminal, the first configuration being used by the first sub-terminal to send the first data using the target transmission method. The method according to claim 20 or 21, wherein, The first configuration includes one or more of the following: Bearer configuration; Wireless link control channel configuration; Logical channel configuration; Configure authorized resources; Security configuration. The method according to any one of claims 14 to 22, wherein the method further comprises: Send a third message to the first sub-terminal, the third message being used to instruct the transmission mode of the first data to be switched to the target transmission mode. The method according to any one of claims 14 to 23, wherein, The first information includes one or more of the following: Information from the first data; Reason for switching; The link signal quality between the first sub-terminal and the head node; The link signal quality between the first sub-terminal and the second sub-terminal. The method according to any one of claims 14 to 19, wherein, The first information is the first data, the configuration used by the first sub-terminal when sending the first data, and/or the header information of the first data, used to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The method according to claim 25, wherein, before receiving the first information from the first sub-terminal, the method further comprises: Send the second and third configurations to the first sub-terminal; The second configuration is used for the first sub-terminal to send the first data using the first transmission method; The third configuration is used by the first sub-terminal to send the first data using the second transmission method. According to the method of claim 15, wherein the first information is the first data, the method further includes: The first data is sent to the core network device. The method according to any one of claims 14 to 27, wherein, The granularity of the first data is one of the following: Service flow granularity; Service quality flow granularity; Bearing particle size; Data packet granularity; Wireless link control channel granularity; Logical channel granularity; Service type granularity; Service granularity; Protocol data unit session granularity; Connection granularity. A data transmission method applied to a head node, the method comprising: Send first information to the first sub-terminal. The first information is used to instruct the transmission mode of the first data to be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. The method according to claim 29, wherein, The target transmission method is the second transmission method. When the transmission method of the first data is the second transmission method, the first data is sent to the second sub-terminal through the header node and the core network device. According to the method of claim 30, before sending the first information to the first sub-terminal, the method further includes: Determine whether to switch the transmission mode of the first data to the target transmission mode based on one or more of the following: The packet latency budget (PDB) of the first data; The link signal quality between the first sub-terminal and the head node; The link signal quality between the head node and the second sub-terminal; The link signal quality between the first sub-terminal and the second sub-terminal; The number of negative feedbacks continuously received from the first sub-terminal and/or the second sub-terminal within a first time period; The load status of the head node; Whether the first event occurred at the first sub-terminal; Did the first event occur in the second sub-terminal? The first event includes one of the following: Radio Link Failure (RLF), Handover (HO), Radio Resource Control (RRC) Connection Re-establishment, and Beam Failure (BF). The method according to claim 30 or 31, wherein the method further comprises: The first data from the first sub-terminal is sent to the core network device. The method according to claim 29, wherein, The target transmission method is the first transmission method. According to the method of claim 33, before sending the first information to the first sub-terminal, the method further includes: Determine whether to switch the transmission mode of the first data to the target transmission mode based on one or more of the following: The first data's PDB; The link signal quality between the first sub-terminal and the head node; The link signal quality between the head node and the second sub-terminal; The link signal quality between the first sub-terminal and the second sub-terminal; The number of positive feedbacks continuously received from the first sub-terminal and/or the second sub-terminal within a first time period; The load status of the head node. The method according to any one of claims 29 to 34, wherein, before sending the first information to the first sub-terminal, the method further comprises: Receive one or more of the following information: The first data's PDB; The link signal quality between the first sub-terminal and the head node; The link signal quality between the head node and the second sub-terminal; The link signal quality between the first sub-terminal and the second sub-terminal. The method according to any one of claims 29 to 35, wherein, before sending the first information to the first sub-terminal, the method further comprises: Send a second message to the core network equipment, the second message being used to request or instruct the transmission mode of the first data to be switched to the target transmission mode. The method according to claim 36, wherein the method further comprises: Receive third information and/or first configuration from the core network device; The third information is used to indicate that the transmission mode of the first data be switched to the target transmission mode; the first configuration is used by the head node to send the first data from the first sub-terminal using the target transmission mode. The method according to claim 37, wherein the method further comprises: Send a second configuration to the first sub-terminal. The second configuration is used by the first sub-terminal to send the first data using the target transmission method. The second configuration is related to the first configuration. The method according to claims 29 to 37, wherein the method further comprises: Send a second configuration to the first sub-terminal, the second configuration being used by the first sub-terminal to send the first data using the target transmission method. The method according to claim 38 or 39, wherein, The second configuration includes one or more of the following: Bearer configuration; Wireless link control channel configuration; Logical channel configuration; Configure authorized resources; Security configuration. The method according to any one of claims 29 to 37, wherein, before sending the first information to the first sub-terminal, the method further comprises: Send the third and fourth configurations to the first sub-terminal; The third configuration is used by the first sub-terminal to send the first data using the first transmission method; The fourth configuration is used by the first sub-terminal to send the first data using the second transmission method. The method according to any one of claims 29 to 41, wherein, The first information includes: information about the first data. The method according to any one of claims 29 to 42, wherein the method further comprises: The first data is received from the first sub-terminal, and the transmission mode of the first data is the target transmission mode. The method according to any one of claims 29 to 43, wherein, The granularity of the first data is one of the following: Service flow granularity; Service quality flow granularity; Bearing particle size; Data packet granularity; Wireless link control channel granularity; Logical channel granularity; Service type granularity; Service granularity; Protocol data unit session granularity; Connection granularity. A data transmission method, applied to a first sub-terminal, the method comprising: Receive first information from the head node, the first information being used to indicate switching the transmission mode of the first data to the target transmission mode, the first data being sent by the first sub-terminal and received by the second sub-terminal; The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. The method according to claim 45, wherein, The target transmission mode is the second transmission mode. When the transmission mode of the first data is the second transmission mode, the first data is sent to the second sub-terminal through the head node and the core network device. The method according to claim 45, wherein, The target transmission method is the first transmission method. The method according to any one of claims 45 to 47, wherein, before receiving the first information from the head node, the method further comprises: Send the packet delay budget (PDB) of the first data to the head node; or, If the first condition is met, the PDB of the first data is sent to the head node. The method according to any one of claims 45 to 48, wherein, before receiving the first information from the head node, the method further comprises: Send the measurement results to the head node; or, If the second condition is met, the measurement result is sent to the head node; The measurement results include: the link signal quality between the first sub-terminal and the head node, and/or, the link signal quality between the first sub-terminal and the second sub-terminal. The method according to any one of claims 45 to 49, wherein the method further comprises: The first sub-terminal receives a second configuration from the head node, the second configuration being used by the first sub-terminal to send the first data using the target transmission method. The method according to claim 50, wherein, The second configuration includes one or more of the following: Bearer configuration; Wireless link control channel configuration; Logical channel configuration; Configure authorized resources; Security configuration. The method according to any one of claims 45 to 49, wherein, before receiving the first information from the head node, the method further comprises: Receive the third and fourth configurations from the head node; The third configuration is used by the first sub-terminal to send the first data using the first transmission method; The fourth configuration is used by the first sub-terminal to send the first data using the second transmission method. The method according to any one of claims 45 to 52, wherein, The first information includes: information about the first data. The method according to any one of claims 45 to 53, wherein the method further comprises: The first data is sent to the head node using the target transmission method. The method according to any one of claims 45 to 54, wherein, The granularity of the first data is one of the following: Service flow granularity; Service quality flow granularity; Bearing particle size; Data packet granularity; Wireless link control channel granularity; Logical channel granularity; Service type granularity; Service granularity; Protocol data unit session granularity; Connection granularity. A data transmission method, applied to a core network device, the method comprising: Send first information to the head node. The first information is used to indicate that the transmission mode of the first data be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. The method according to claim 56, wherein, The target transmission method is the second transmission method. When the transmission method of the first data is the second transmission method, the first data is sent to the second sub-terminal through the header node and the core network device. The method according to claim 56, wherein, The target transmission method is the first transmission method. The method according to any one of claims 56 to 58, wherein, before sending the first information to the head node, the method further comprises: Determine whether to switch the transmission mode of the first data to the target transmission mode based on one or more of the following: The packet latency budget (PDB) of the first data; Has the first sub-terminal been switched over? Has the second sub-terminal been switched over? The load status of the core network equipment. The method according to any one of claims 56 to 59, wherein, before sending the first information to the head node, the method further comprises: Receive the PDB of the first data. The method according to any one of claims 56 to 60, wherein the method further comprises: Send a first configuration to the head node, the first configuration being used by the head node to send the first data from the first sub-terminal using the target transmission method. The method according to any one of claims 56 to 61, wherein, The first information includes: information about the first data. The method according to any one of claims 56 to 62, wherein, The granularity of the first data is one of the following: Service flow granularity; Service quality flow granularity; Bearing particle size; Data packet granularity; Wireless link control channel granularity; Logical channel granularity; Service type granularity; Service granularity; Protocol data unit session granularity; Connection granularity. A data transmission method applied to a head node, the method comprising: Receive first information from the core network device, the first information being used to instruct the switching of the transmission mode of the first data to the target transmission mode, the first data being sent by the first sub-terminal and received by the second sub-terminal; The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. The method according to claim 64, wherein, The target transmission method is the second transmission method. When the transmission method of the first data is the second transmission method, the first data is sent to the second sub-terminal through the network device and the core network device. The method according to claim 64, wherein, The target transmission method is the first transmission method. The method according to any one of claims 64 to 66, wherein, before receiving the first information from the core network device, the method further comprises: The PDB of the first data is sent to the core network equipment. The method according to any one of claims 64 to 67, wherein the method further comprises: The head node receives a first configuration from the core network device, the first configuration being used by the head node to send the first data from the first sub-terminal using the target transmission method. The method according to claim 68, wherein the method further comprises: Send a second configuration to the first sub-terminal. The second configuration is used by the first sub-terminal to send the first data using the target transmission method. The second configuration is related to the first configuration. The method according to any one of claims 64 to 68, wherein the method further comprises: Send a second configuration to the first sub-terminal, the second configuration being used by the first sub-terminal to send the first data using the target transmission method. The method according to claim 69 or 70, wherein, The second configuration includes one or more of the following: Bearer configuration; Wireless link control channel configuration; Logical channel configuration; Configure authorized resources; Security configuration. The method according to any one of claims 64 to 68, wherein, before receiving the first information from the core network device, the method further comprises: Send the third and fourth configurations to the first sub-terminal; The third configuration is used by the first sub-terminal to send the first data using the first transmission method; The fourth configuration is used by the first sub-terminal to send the first data using the second transmission method. The method according to any one of claims 64 to 72, wherein the method further comprises: Send a second message to the first sub-terminal, the second message being used to instruct the transmission mode of the first data to be switched to the target transmission mode. The method according to claim 73, wherein, The second information includes: information about the first data. The method according to any one of claims 64 to 74, wherein, The first information includes: information about the first data. The method according to any one of claims 64 to 75, wherein, The granularity of the first data is one of the following: Service flow granularity; Service quality flow granularity; Bearing particle size; Data packet granularity; Wireless link control channel granularity; Logical channel granularity; Service type granularity; Service granularity; Protocol data unit session granularity; Connection granularity. A data transmission apparatus, the apparatus comprising: The first communication unit is configured to send first information to the head node. The first information is used to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The first data is sent by the device and received by the second sub-terminal. The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. A data transmission apparatus, the apparatus comprising: The second communication unit is configured to receive first information from the first sub-terminal. The first information is used to request or indicate that the transmission mode of the first data be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission method is either a first transmission method or a second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the device. A data transmission apparatus, the apparatus comprising: The third communication unit is configured to send first information to the first sub-terminal. The first information is used to instruct the transmission mode of the first data to be switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission method is either a first transmission method or a second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the device. A data transmission apparatus, the apparatus comprising: The fourth communication unit is configured to receive first information from the head node, the first information being used to indicate switching the transmission mode of the first data to the target transmission mode, the first data being sent by the device and received by the second sub-terminal; The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. A data transmission apparatus, the apparatus comprising: The fifth communication unit is configured to send first information to the head node. The first information is used to indicate that the transmission mode of the first data is switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission method is either the first transmission method or the second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the head node. A data transmission apparatus, the apparatus comprising: The sixth communication unit is configured to receive first information from the core network device. The first information is used to indicate that the transmission mode of the first data is switched to the target transmission mode. The first data is sent by the first sub-terminal and received by the second sub-terminal. The target transmission method is either a first transmission method or a second transmission method. When the transmission method of the first data is the first transmission method, the first data is sent to the second sub-terminal through the device. A communication device, the communication device comprising: Memory, used to store computer programs; A processor, connected to the memory, is configured to call and run the computer program from the memory to implement the method as described in any one of claims 1 to 13, or the method as described in any one of claims 14 to 28, or the method as described in any one of claims 29 to 44, or the method as described in any one of claims 45 to 55, or the method as described in any one of claims 56 to 63, or the method as described in any one of claims 64 to 76; A transceiver is used to receive and send information when exchanging information with other devices. A chip, the chip comprising: A processor for retrieving and running a computer program from memory, causing a device having the chip mounted to perform the method as claimed in any one of claims 1 to 13, or the method as claimed in any one of claims 14 to 28, or the method as claimed in any one of claims 29 to 44, or the method as claimed in any one of claims 45 to 55, or the method as claimed in any one of claims 56 to 63, or the method as claimed in any one of claims 64 to 76; A transceiver is used to receive and send information during the exchange of information with a device or chip. A computer-readable storage medium for storing a computer program that causes a computer to perform the method as claimed in any one of claims 1 to 13, or the method as claimed in any one of claims 14 to 28, or the method as claimed in any one of claims 29 to 44, or the method as claimed in any one of claims 45 to 55, or the method as claimed in any one of claims 56 to 63, or the method as claimed in any one of claims 64 to 76.