Switching method and device, storage medium and program product

Abstract

The invention provides a switching method and device, a storage medium and a program product, relates to the technical field of communication, and is used for reducing network interruption duration in a switching process of cross-access network equipment. The method comprises: a source access network device sending a switching request message to a target access network device, the switching request message being used for requesting to switch a first terminal to the target access network device; wherein the first terminal is connected with the source access network equipment through a first path and a second path, the first path is a direct path between the first terminal and the source access network equipment, and the second path is an indirect path through which the first terminal is connected with the source access network equipment through the second terminal; and receiving a switching request response from the target access network equipment.

Description

Technical Field

[0001] The present disclosure relates to the field of communication technology, and in particular to a switching method, device, storage medium and program product. Background Art

[0002] Terminal aggregation (UE Aggregation) is a terminal collaboration technology that allows multiple terminals to share resources through direct links, thereby improving the uplink capability of a single terminal. Among them, the remote terminal (Remote UE) can connect to the base station (gNB) with the help of a relay terminal (Relay UE or Aggregated UE) to access the network. In some scenarios, such as wireless transmission service load adjustment, activation operation and maintenance, equipment failure, terminal movement, etc., the remote terminal may need to switch from one base station to another. However, during the cross-base station switching process of terminal aggregation, network interruption will occur, thereby affecting the continuity of network services. Summary of the invention

[0003] The present disclosure provides a switching method, an apparatus, a storage medium and a program product for reducing the network interruption duration during the switching process of cross-access network devices.

[0004] In order to achieve the above objectives, the present disclosure adopts the following technical solutions:

[0005] In a first aspect, the present disclosure provides a handover method, applied to a source access network device, the method comprising:

[0006] Sending a switching request message to a target access network device, where the switching request information is used to request that the first terminal be switched to the target access network device; wherein the first terminal is connected to the source access network device through a first path and a second path, the first path being a direct path between the first terminal and the source access network device, and the second path being an indirect path connecting the first terminal to the source access network device through the second terminal;

[0007] Receive a handover request response from the target access network device.

[0008] In a second aspect, the present disclosure further provides a switching method, which is applied to a target access network device, and the method includes:

[0009] Receiving handover request information from a source access network device, where the handover request information is used to request handover of the first terminal to a target access network device, and to request maintaining direct path connectivity during the handover process, and / or maintaining indirect path connectivity during the handover process;

[0010] sending a handover request response to the source access network device, where the handover request response includes second indication information, where the second indication information is used to indicate whether to agree to maintain direct path connectivity during the handover process, and /

[0011] Or, whether to agree to keep the indirect path connected.

[0012] In a third aspect, the present disclosure further provides a switching method, applied to a first terminal, the method comprising:

[0013] receiving second indication information from a source access network device, where the second indication information is used to instruct the first terminal to switch to a target access network device, and to maintain at least one path connection between the first terminal and the source access network device during the switching process;

[0014] Based on the second indication information, a connection is established with the target access network device.

[0015] In a fourth aspect, the present disclosure further provides a switching method, applied to a second terminal, the method comprising:

[0016] During the process of the first terminal switching from the source access network device to the target access network device, data transmission on the indirect path between the first terminal and the source access network device is maintained, or data transmission on the indirect path between the first terminal and the target access network device is maintained.

[0017] In a fifth aspect, the present disclosure provides a communication device, applied to a source access network device, the device comprising:

[0018] A sending module, configured to send a switching request message to a target access network device, wherein the switching request message is used to request that the first terminal be switched to the target access network device; wherein the first terminal is connected to the source access network device via a first path and a second path, wherein the first path is a direct path between the first terminal and the source access network device, and the second path is an indirect path between the first terminal and the source access network device via the second terminal;

[0019] The receiving module is used to receive a switching request response from a target access network device.

[0020] In a sixth aspect, the present disclosure further provides a communication device, applied to a target access network device, the device comprising:

[0021] A receiving module, configured to receive switching request information from a source access network device, wherein the switching request information is used to request that the first terminal be switched to a target access network device, and to request that a direct path connection be maintained during the switching process, and / or that an indirect path connection be maintained during the switching process;

[0022] The sending module is used to send a switching request response to the source access network device, where the switching request response includes second indication information, and the second indication information is used to indicate whether to agree to maintain direct path connectivity and / or whether to agree to maintain indirect path connectivity during the switching process.

[0023] In a seventh aspect, the present disclosure further provides a communication device, applied to a first terminal, the device comprising:

[0024] A receiving module, configured to receive second indication information from a source access network device, the second indication information being used to instruct the first terminal to switch to a target access network device, and to maintain at least one path connection between the first terminal and the source access network device during the switching process;

[0025] The processing module is used to establish a connection with the target access network device based on the second indication information.

[0026] In an eighth aspect, the present disclosure further provides a communication device, applied to a second terminal, the device comprising:

[0027] The processing module is used to maintain data transmission on an indirect path between the first terminal and the source access network device during the process of the first terminal switching from the source access network device to the target access network device, or to maintain data transmission on an indirect path between the first terminal and the target access network device.

[0028] In a ninth aspect, a communication device is provided, comprising: a processor and a memory; the memory stores instructions executable by the processor; when the processor is configured to execute the instructions, the communication device implements any one of the methods provided in the first to fourth aspects above.

[0029] In a tenth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer executes any one of the methods provided in the first to fourth aspects.

[0030] In an eleventh aspect, a computer program product comprising computer instructions is provided. When the computer instructions are executed on a computer, the computer executes any one of the methods provided in the first to fourth aspects.

[0031] Based on the technical solution provided by the present disclosure, the source access network device and the target access network device can determine through signaling interaction that the data transmission of the direct path is maintained during the switching process, and / or that the data transmission of the indirect path is maintained during the switching process. Therefore, during the switching process of terminal aggregation across access network devices, the terminal can maintain data transmission with the source access network device in the process of switching to the target access network device based on the switching configuration of the access network device. Compared with completely disconnecting the connection with the source access network device and then switching to the target access network device, this can reduce the network interruption time of the terminal, thereby maintaining business continuity when switching across access network devices, and is also suitable for terminal mobility scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide further understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation on the technical solution of the present disclosure.

[0033] Figure 1 A schematic diagram of the architecture of a communication system provided by an embodiment of the present disclosure;

[0034] Figure 2 A schematic diagram of a connection method provided in an embodiment of the present disclosure;

[0035] Figure 3 A flowchart of a switching method provided by an embodiment of the present disclosure;

[0036] Figure 4 A schematic diagram of another connection method provided in an embodiment of the present disclosure;

[0037] Figure 5 A schematic diagram of another connection method provided in an embodiment of the present disclosure;

[0038] Figure 6 A schematic diagram of another connection method provided in an embodiment of the present disclosure;

[0039] Figure 7 A flowchart of another switching method provided by an embodiment of the present disclosure;

[0040] Figure 8 A flowchart of another switching method provided by an embodiment of the present disclosure;

[0041] Fig. 9 A flowchart of another switching method provided by an embodiment of the present disclosure;

[0042] Fig.10 A schematic diagram of the composition of a communication device provided in an embodiment of the present disclosure;

[0043] Fig.11A schematic diagram of another communication device provided in an embodiment of the present disclosure;

[0044] Fig.12 A schematic diagram of another communication device provided in an embodiment of the present disclosure;

[0045] Fig.13 A schematic diagram of another communication device provided in an embodiment of the present disclosure;

[0046] Fig.14 A schematic diagram of the structure of a communication device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0048] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and other forms thereof, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open, inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0049] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0050] In the embodiments of the present disclosure, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present disclosure should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0051] Additionally, the use of “based on” is meant to be open and inclusive, as a process, step, calculation, or other action “based on” one or more stated conditions or values ​​may, in practice, be based on additional conditions or values ​​beyond those stated.

[0052] Terminal (user equipment, UE) aggregation technology, also known as UE aggregation, Remote UE can be connected to the base station through a direct link and connected to the network through another UE (Relay UE or AggregatedUE) using non-standardized UE-UE interconnection. UE aggregation can provide terminals with applications that require high uplink bit rates. For example, when ordinary UEs at the edge of a cell are limited by the uplink UE transmission power and cannot achieve the required bit rate, this technology can be used to improve it. In addition, UE aggregation can also improve service reliability, stability and reduce latency. When the channel conditions of one terminal deteriorate, another terminal can be used to reduce the unstable traffic performance caused by the change in channel conditions.

[0053] Since the Remote UE and Relay UE need to be under the same gNB, when the Remote UE switches across base stations, the reliability, stability and delay of the service cannot be guaranteed. This problem is particularly prominent in high-demand scenarios such as wireless Internet of Vehicles. Since the terminals in the Internet of Vehicles (such as vehicle terminals) frequently cross the coverage of different base stations during driving, switching occurs frequently. Each switching may bring a long service interruption time, which poses a challenge to the real-time service requirements in the Internet of Vehicles. The service interruption time caused by switching in the actual network is at least 70ms, usually greater than 100ms, and the interruption time is long. Among the current technologies for reducing the switching interruption time, the dual activation protocol stack (DAPS) is an effective method, but this technology has high requirements for the terminal, especially when switching between cells on the same frequency, and its universality is low. UE aggregation technology provides a new idea for solving the mobility problem. By aggregating the resources of multiple UEs (including Remote UE and Relay UE), the requirements for a single UE can be reduced to a certain extent, while improving the overall reliability and stability. During the cross-base station switching process of terminal aggregation, how to reduce network interruption time and improve business continuity is a technical problem that needs to be solved urgently in related fields.

[0054] In view of this, the present disclosure provides a switching method, based on which a source access network device can send a switching request message to a target access network device, and the switching request information is used to request that a first terminal be switched to a target access network device; wherein the first terminal is connected to the source access network device through a first path and a second path, the first path being a direct path between the first terminal and the source access network device, and the second path being an indirect path through which the first terminal is connected to the source access network device through the second terminal; and receiving a switching request response from the target access network device. In this way, the source access network device and the target access network device can determine through signaling interaction that data transmission of a direct path is maintained during the switching process, and / or that data transmission of an indirect path is maintained during the switching process. Thus, in the process of switching of terminal aggregation across access network devices, the terminal can maintain data transmission with the source access network device in the process of switching to the target access network device based on the switching configuration of the access network device, which can reduce the network interruption time of the terminal compared to completely disconnecting the connection with the source access network device and then switching to the target access network device, thereby maintaining service continuity during switching across access network devices, and is also applicable to terminal mobility scenarios.

[0055] The technical solutions provided by the embodiments of the present disclosure can be applied to various mobile communication networks, such as long term evolution (LTE) systems, various versions based on LTE evolution, fifth generation mobile communication technology (5G) systems (including but not limited to new radio (NR) mobile communication system environments, ambient internet of things (Ambient IoT) and other communication systems). In addition, the signal transmission method provided by the embodiments of the present disclosure can also be applied to future-oriented communication systems (such as 6G communication systems) or networks of multiple communication convergence systems, and the embodiments of the present disclosure are not limited to this.

[0056] Figure 1 FIG. 1 is a schematic diagram showing an architecture of a communication system provided by an embodiment of the present disclosure. Figure 1 As shown, the communication system includes one or more terminals 10 and one or more access network devices 20.

[0057] In some embodiments, the terminal 10 may be a device with wireless transceiver function, which may be deployed on land, including indoors or outdoors, handheld, wearable or vehicle-mounted; it may also be deployed on the water surface (such as a ship, etc.); it may also be deployed in the air (such as an airplane, a balloon, and a satellite, etc.). The terminal may be a mobile phone, a tablet computer (Pad), a computer with wireless transceiver function, a virtual reality (VR) terminal, an augmented reality (AR) terminal, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. The embodiments of the present disclosure do not limit the application scenarios. A terminal may sometimes also be referred to as a user, user equipment (UE), access terminal, UE unit, UE station, mobile station, mobile station, remote station, remote terminal, mobile device, UE terminal, wireless communication equipment, UE agent or UE device, etc., but the embodiments of the present disclosure are not limited to this.

[0058] In some embodiments, the access network device 20 is used to provide wireless access services for multiple terminals, which can be a base station. Specifically, a base station provides a service coverage area (also called a cell). Terminals entering the area can communicate with the base station through wireless signals to receive the wireless access services provided by the base station.

[0059] In some embodiments, the access network device 20 can be a base station or an evolved base station (eNB or eNodeB) in long term evolution (LTE), long term evolution advanced (LTEA), a base station device in a 5G network, or a base station in a future communication system, etc. The base station may include various macro base stations, micro base stations, home base stations, wireless remote stations, reconfigurable intelligent surfaces (RIS), routers, wireless fidelity (WIFI) devices, and other network side devices.

[0060] In some embodiments, the one or more terminals 10 may include a Remote UE and a multi-purpose relay user equipment (MP Relay UE). Figure 2 As shown, by using UE aggregation technology, the Remote UE can be indirectly connected to the access network device 20 through the MP Relay UE of non-standardized UE-UE interconnection (path 2), and directly connected to the access network device 20 through the Uu interface (path 1).

[0061] It should be noted that Figure 1 This is just an exemplary architecture diagram. Figure 1 The number of devices included in the Figure 1 In addition to the devices shown, the communication system may also include other devices, such as core network devices.

[0062] The application scenarios of the embodiments of the present disclosure are not limited. The system architecture and business scenarios described in the embodiments of the present disclosure are intended to more clearly illustrate the technical solutions of the embodiments of the present disclosure, and do not constitute a limitation on the technical solutions provided by the embodiments of the present disclosure. It is known to those skilled in the art that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided by the embodiments of the present disclosure are also applicable to similar technical problems.

[0063] The embodiments provided by the present disclosure are described in detail below in conjunction with the accompanying drawings.

[0064] like Figure 3 As shown, an embodiment of the present disclosure provides a switching method, the method comprising:

[0065] S101. A source access network device sends a switching request message to a target access network device.

[0066] The switching request information is used to request that the first terminal be switched to a target access network device.

[0067] In some embodiments, the first terminal is connected to the source access network device through a first path and a second path, the first path is a direct path between the first terminal and the source access network device, and the second path is an indirect path connecting the first terminal to the source access network device through the second terminal. Figure 2 For example, the first path here is Figure 2 Path 1 in the second path is Figure 2 In path 2, the first terminal is the RemoteUE and the second terminal is the MP Relay UE.

[0068] In some embodiments, the handover request message is further used to request to maintain data transmission on a direct path during the handover process, and / or to maintain data transmission on an indirect path during the handover process.

[0069] In some embodiments, during the cross-access network device handover process of terminal aggregation, the Remote UE first switches to the target access network device, and then the Relay UE switches to the target access network device. Alternatively, the Relay UE first switches to the target access network device, and then the Remote UE switches to the target access network device.

[0070] S102: The target access network device sends a switching request response to the source access network device.

[0071] In some embodiments, the handover request response includes first indication information, where the first indication information is used to indicate whether to agree to maintain data transmission on a direct path and / or whether to agree to maintain data transmission on an indirect path during the handover process.

[0072] S103. The source access network device sends second indication information to the first terminal.

[0073] The second indication information is used to instruct the first terminal to switch to the target access network device, and to keep the first terminal connected to the source access network device during the switching process.

[0074] In some embodiments, the second indication information includes at least one of the following: target cell information, indication information of whether to maintain direct path connectivity during the handover process, and indication information of whether to maintain indirect path connectivity.

[0075] The target cell information includes relevant information of the target cell to which the first terminal is to switch, such as the identifier of the target cell, where the target cell refers to the cell-radio network temporary identifier (C-RNTI) allocated to the first terminal, the switching timer (T304), and the random access resource configuration. T304 is used to control the time of the terminal during the switching process.

[0076] Exemplarily, when the source access network device receives a switching request response from the source access network device, it can send switching-related configuration information, i.e., second indication information, to the first terminal via a radio resource control (RRC) reconfiguration message, so that the first terminal switches to the target access network device based on the second indication information.

[0077] In some embodiments, the second indication information is indication information with a terminal as the granularity. Alternatively, the second indication information is indication information with a data radio bearer (DRB) as the granularity. That is, the first indication information may be configured per UE or per DRB.

[0078] S104. The first terminal establishes a connection with the target access network device based on the second indication information.

[0079] In one example, when the Remote UE switches to the target access network device first and then the Relay UE switches to the target access network device, the second indication information can be specifically used to instruct the first terminal to stop data transmission on the first path and maintain data transmission on the second path, and connect to the target access network device via a third path. The third path is a path for the first terminal to directly connect to the target access network device.

[0080] For example, Figure 4 As shown, based on the second indication information, the Remote UE can stop data transmission on path 1 and maintain data transmission between path 2 and the source access network device (source gNB), and connect to the target access network device (target gNB) through path 3 (ie, the third path), and path 3 includes: first terminal <-> target access network device.

[0081] In another example, when the Remote UE switches to the target access network device first and then the Relay UE switches to the target access network device, the second indication information can be specifically used to indicate to stop the data transmission of the first path and maintain the data transmission of the second path, and access the target access network device through an indirect path. Exemplarily, the path of the first terminal to the target access network device can be: first terminal <-> second terminal <-> source access network device <-> target access network device. Since the second terminal has not yet switched to the target access network device, it is connected to the source access network device, and the data transmission can be forwarded through the source access network device.

[0082] In another example, when the Relay UE is first switched to the target access network device and then the Remote UE is switched to the target access network device, the second indication information can be specifically used to instruct the first terminal to maintain data transmission on the first path and to connect to the target access network device through a fourth path, where the fourth path is a path for the first terminal to connect to the target access network device through the target terminal. The target terminal includes an aggregated terminal that has been switched to the target access network device, and the target terminal may also be a second terminal or other possible terminals.

[0083] For example, Figure 5As shown, the Relay UE has switched to the target access network device, and path 2 is disconnected at this time. Based on the second indication information, the Remote UE can maintain the data transmission between path 1 and the source access network device. In addition, the Remote UE can also connect to the target access network device through path 4 (i.e., the fourth path), and path 4 includes: first terminal <-> target terminal <-> target access network device.

[0084] In another example, when the Relay UE switches to the target access network device first and then the Remote UE switches to the target access network device, the second indication information is specifically used to instruct the first terminal to stop data transmission on the first path, maintain data transmission with the source access network device through the fifth path, and connect to the target access network device through the third path. The fifth path is a path for the first terminal to indirectly connect to the source access network device through the target terminal and the target access network device. The target terminal includes an aggregated terminal that has been switched to the target access network device, and the target terminal may also be a second terminal or other possible terminals.

[0085] For example, Figure 6 As shown, the Relay UE has switched to the target access network device, and path 2 is disconnected at this time. Based on the second indication information, the Remote UE can stop the data transmission between path 1 and the source access network device. In addition, the Remote UE can also connect to the source access network device through path 5 (that is, the fifth path), and connect to the target access network device through path 3. Among them, path 5 includes: first terminal <-> target terminal <-> target access network device <-> source access network device. Path 3 includes: first terminal <-> target access network device.

[0086] Based on the technical solution provided by the present disclosure, the source access network device and the target access network device can determine through signaling interaction that the data transmission of the direct path is maintained during the switching process, and / or that the data transmission of the indirect path is maintained during the switching process. Therefore, during the switching process of terminal aggregation across access network devices, the terminal can maintain data transmission with the source access network device in the process of switching to the target access network device based on the switching configuration of the access network device. Compared with completely disconnecting the connection with the source access network device and then switching to the target access network device, this can reduce the network interruption time of the terminal, thereby maintaining business continuity when switching across access network devices, and is also suitable for terminal mobility scenarios.

[0087] In the case where the Remote UE is first switched to the target access network device, and then the Relay UE is switched to the target access network device, such as Figure 7 As shown, the present disclosure also provides another switching method, including:

[0088] S201. The first terminal sends a measurement report to a source access network device.

[0089] Exemplarily, the connection between the first terminal and the source access network device can refer to Figure 2 The examples shown are not repeated here. In the process of the first terminal and its aggregated terminal (second terminal) gradually moving away from the source access network device to the target access network device, if the first terminal or the second terminal triggers a measurement report, the first terminal or the second terminal can perform a measurement and send the obtained measurement report to the source access network device. The measurement report may include the measurement results of the serving cell, the measurement results of the candidate cell, etc. Furthermore, after receiving the measurement report, the source access network device can determine whether to switch the terminal (the first terminal and the second terminal).

[0090] S202: The source access network device sends a switching request message to the target access network device.

[0091] For a detailed description of step S202, reference may be made to the description of step S101 above.

[0092] Exemplarily, when the source access network device determines to switch the first terminal, a handover request message (HANDOVER REQUEST) may be sent to the target access network device. In order to retain the data transmission of the original direct path (first path) or the original indirect path (second path) during the handover process, the source access network device may add indication information of whether to retain the path on the source access network device side in the handover request message, such as at least one of the following: indication information of retaining the direct path (directPathMaintain), indication information of retaining the indirect path (indirectPathMaintain).

[0093] In the case where the Remote UE switches to the target access network device first and then the Relay UE switches to the target access network device, the indication information may include indication information for retaining the indirect path. At this time, the first terminal is configured to stop data transmission on the second path, and / or the second terminal has been configured to switch to the target access network device.

[0094] In some embodiments, the information in the above-mentioned handover request message (indication information on whether to retain the path on the device side of the source access network) is indication information with terminal as the granularity, or indication information with data radio bearer as the granularity. That is, the indication information on whether to retain the path on the device side of the source access network can be configured per UE or per DRB. For example, in the case where the information in the handover request message is indication information with terminal as the granularity, all bearers of the terminal involving direct paths or indirect paths apply the indication information. In the case where the information in the handover request message is indication information with DPB as the granularity, only the relevant DRB applies the indication information.

[0095] S203: The target access network device sends a switching request response to the source access network device.

[0096] The detailed description of step S203 may refer to the description of step S102 above.

[0097] Exemplarily, the target access network device receives the switching request message and may perform access control on the first terminal to determine whether to allow it to access the network, that is, whether to allow the first terminal to switch from the source access network device to the target access network device.

[0098] In the case where the target access network device allows the first terminal to switch, a handover request response (HANDOVER REQUEST ACKNOWLEDGE) may be sent to the source access network device. In addition, the target access network device may agree to retain part of the data transmission carried on the original direct path or indirect path. Thus, the handover request response sent by the target access network device to the source access network device may include indication information of whether to retain the source access network device's measured path (that is, the first indication information in the present disclosure), and the indication information includes at least one of the following: indication information of agreeing to maintain data transmission on the direct path, indication information of disagreeing to maintain data transmission on the direct path, indication information of agreeing to maintain data transmission on the indirect path, and indication information of disagreeing to maintain data transmission on the indirect path.

[0099] In the case where the Remote UE is first switched to the target access network device and then the Relay UE is switched to the target access network device, the indication information may include indication information of not agreeing to maintain data transmission over a direct path and indication information of agreeing to maintain data transmission over an indirect path.

[0100] In some embodiments, the first indication information is indication information with a terminal as the granularity, or indication information with a data radio bearer as the granularity. That is, the first indication information may be configured per UE or per DRB. In some embodiments, the source access network device and the target access network device may also negotiate to establish an Xn interface tunnel for forwarding the second terminal data during the relevant handover signaling interaction process.

[0101] S204. The source access network device sends second indication information to the first terminal.

[0102] The detailed description of step S204 may refer to the description of step S102 above.

[0103] In some embodiments, the source access network device may send switching-related configuration information (ie, second indication information) to the first terminal via an RRC reconfiguration message, including at least one of target cell information and indication information for maintaining indirect path connectivity during the switching process.

[0104] The target cell information includes relevant information of the target cell to which the first terminal is to switch, such as the identifier of the target cell, where the target cell refers to the cell-radio network temporary identifier (C-RNTI) allocated to the first terminal, the switching timer (T304), and the random access resource configuration. T304 is used to control the time of the terminal during the switching process.

[0105] Exemplarily, when the source access network device receives the handover request response from the target access network device, it can send an RRC reconfiguration message to the first terminal to reconfigure the RRC layer of the first terminal so that it adapts to the new network environment and the requirements of the target access network device. Thus, the source access network device can send the second indication information to the first terminal through the RRC reconfiguration message.

[0106] At this time, the second indication information can be specifically used to instruct the first terminal to stop data transmission on the first path and maintain data transmission on the second path, and connect to the target access network device through a third path, wherein the third path is a path for direct connection between the first terminal and the target access network device.

[0107] After receiving the second indication information, the first terminal may stop sending and receiving data on the Uu port with the source access network device (first path). In the case where the second indication information includes indication information for maintaining connectivity of the indirect path, the first terminal may continue to send and receive data on the N3C indirect path (second path) during the switching. Exemplary, uplink (UL) data transmission path: first terminal->second terminal->source access network device->UPF. Downlink (DL) data transmission path: 1) UPF->source access network device->second terminal->first terminal, 2) UPF->source access network device->target access network device. At this time, after the source access network device receives the downlink data from the UPF, on the one hand, it can continue to send the data to the first terminal through the indirect path (second path) on the source access network device, and on the other hand, it can forward the data to the target access network device.

[0108] In some embodiments, the first terminal may further maintain independent security contexts and robust header compression (ROHC) contexts for data transmission over the second path and the third path, respectively, and maintain a common packet data convergence protocol (PDCP) sequence number allocation.

[0109] Exemplarily, during the handover execution, the first terminal may also maintain separate security contexts and robust header compression (ROHC) header compressor contexts for uplink transmissions to the source access network device and the target access network device, respectively. The first terminal may also maintain a common uplink packet data convergence protocol (PDCP) sequence number allocation. Thus, the first terminal may receive downlink data sent by the source access network device or the target access network device using the security context and ROHC header decompression function associated with the source access network device or the target access network device, respectively. In addition, the first terminal may also simultaneously maintain the general functions of reordering, duplicate detection and discarding, and transmitting the PDCP service data unit (SDU) to the upper layer in sequence.

[0110] S205. The first terminal sends an RRC reconfiguration completion message to the target access network device.

[0111] Exemplarily, after the first terminal successfully accesses the target access network device, it can send an RRC reconfiguration completion message to the target access network device.

[0112] In some embodiments, when connected to the target access network device through the third path, the uplink data of the first terminal can also be switched from being transmitted to the source access network device to being transmitted to the target access network device.

[0113] Exemplarily, the first terminal may no longer send uplink data through the indirect path (second path) on the source access network device side, and transfer the uplink data transmission to the target access network device. At this time, since the uplink data of the first terminal is transferred from the source access network device to the target access network device, lossless transmission of the uplink data needs to be considered. Based on UE aggregation, it is assumed that the first terminal can determine the data packets that the second terminal has successfully / unsuccessfully sent to the source access network device (for example, by receiving the radio link control protocol RLC confirmation response ack / negative response nack from the Uu port) according to the N3C ideal interface, so that the first terminal can start transmitting to the target access network device from the first data packet confirmed to be received by the source access network device RLC, thereby realizing the transfer of uplink data transmission to the target access network device.

[0114] S206: The target access network device sends a switching success indication message to the source access network device.

[0115] Exemplarily, after the target access network device receives the RRC reconfiguration completion message from the first terminal, it may send handover success indication information (HANDOVER SUCCESS) to the source access network device.

[0116] Furthermore, after receiving the switching success indication information, the source access network device can stop sending downlink data on the indirect path (second path) on the source access network device side, receive downlink data from the UPF and forward it to the target access network device. In addition, the source access network device stops sending uplink data packets of the first terminal to the UPF, but forwards the uplink data packets to the target access network device.

[0117] In some embodiments, the source access network device sends a sequence number (SN) state transfer to the target access network device.

[0118] In the process of transferring downlink data from the source access network device to the target access network device, lossless transmission of downlink data also needs to be considered. Based on UE aggregation, assuming that the downlink data successfully sent by the source access network device to the second terminal is successfully forwarded by the second terminal to the first terminal (N3C ideal interface), the source access network device needs to forward the downlink data packets that have not been successfully received by the second terminal to the target access network device. Alternatively, the source access network device forwards all cached downlink data packets of the first terminal (even if the data packets have been successfully received by the second terminal) to the target access network device.

[0119] When the transmission paths of the uplink and downlink data of the first terminal are switched, the target access network device may send an RRC reconfiguration message to the first terminal to instruct the first terminal to release the relevant configurations on the source access network device side (e.g., security context associated with the source access network device, ROHC header compression, and other configurations). For example, it may include an indirect path release indication on the source access network device side and a direct path release indication on the source access network device side.

[0120] In some embodiments, for the aggregated terminal (second terminal) on the indirect path on the source access network device side, the second terminal can continue to forward the uplink and downlink data of the first terminal until the Uu RLC channel is released, or receives the indication information sent by the source access network device to release the first terminal.

[0121] In some embodiments, after the first terminal completes the handover, the second terminal is triggered to perform the handover. Furthermore, after the second terminal switches to the target access network device, the access network device may configure an indirect path addition for the first terminal.

[0122] based on Figure 6 In the embodiment shown, the Remote UE is first switched to the target access network device, and then the Relay UE is switched to the target access network device, so that the delay impact is small, and during the switching process, the data transmission of the first path is stopped and the data transmission of the second path is maintained, and the target access network device is connected through the third path. In this way, the network interruption time of the terminal can be reduced, so that service continuity can be maintained when switching across access network devices.

[0123] In the case where the Relay UE is first switched to the target access network device and then the Remote UE is switched to the target access network device, such as Figure 8 As shown, the present disclosure also provides another switching method, including:

[0124] S301. The first terminal sends a measurement report to a source access network device.

[0125] Exemplarily, the connection between the first terminal and the source access network device can refer to Figure 2 The examples shown are not repeated here. In the process of the first terminal and its aggregated terminal (second terminal) gradually moving away from the source access network device to the target access network device, if the first terminal or the second terminal triggers a measurement report, the first terminal or the second terminal can perform a measurement and send the obtained measurement report to the source access network device. The measurement report may include the measurement results of the serving cell, the measurement results of the candidate cell, etc. Furthermore, after receiving the measurement report, the source access network device can determine whether to switch the terminal (the first terminal and the second terminal).

[0126] S302: The source access network device sends a switching request message to the target access network device.

[0127] For a detailed description of step S302, reference may be made to the description of step S101 above.

[0128] Exemplarily, when the Relay UE (second terminal) first switches to the target access network device, the source access network device determines to send a handover message to the first terminal, and can send a handover request message to the target access network device. In some embodiments, before executing step S302, the source access network device can send a third indication information to the second device, and the third indication information is used to instruct the second terminal to switch to the target access network device.

[0129] During the switching of the second terminal, the first terminal can transmit data to the source access network device through a direct path. Before configuring the second terminal to switch, the source access network device can also configure the first terminal to release the split bearer (Split Bearer) and the indirect bearer (Indirect Bearer) transmitted through the indirect path, so that the corresponding service data can be configured to use the Uu bearer on the direct path to transmit data.

[0130] In some embodiments, the handover request message includes at least one of the following:

[0131] The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device (for example, F1AP UE ID), the identifier of the target terminal (for example, F1AP UE ID), the wireless network temporary identifier (C-RNTI) of the target terminal, and indication information for maintaining data transmission on a direct path during the switching process.

[0132] Exemplarily, the Relay UE first switches to the target access network device (the second path has ended data transmission). When the source access network device decides to initiate a handover of the first terminal, if the source access network device hopes to maintain data transmission on the direct path (first path) on the source access network device side during the handover of the first terminal, and connect to the target access network device through an indirect path (fourth path), such as Figure 5 shown.

[0133] In some embodiments, the information in the above-mentioned handover request message (indication information on whether to retain the path on the device side of the source access network) is indication information with terminal granularity, or indication information with data radio bearer granularity. That is, the indication information on whether to retain the path on the device side of the source access network can be configured per UE or per DRB.

[0134] S303. The target access network device sends an RRC reconfiguration message to the target terminal.

[0135] In the case where the target access network device allows the first terminal to switch, the target access network device may accept the first terminal to connect to itself through the target terminal (indicated by the source access network device), or the target access device itself may select a target terminal for the first terminal from the candidate aggregation terminals. The target terminal includes the aggregation terminal that has been switched to the target access network device, and the target terminal may also be the second terminal or other possible terminals.

[0136] It should be understood that Figure 8 The technical solution of the embodiment of the present disclosure is exemplarily described by taking the target terminal as the second terminal, and the target terminal may also be other possible aggregation terminals that have been switched to the target access network device.

[0137] In some embodiments, the RRC reconfiguration message includes at least one of the following:

[0138] The radio network temporary identifier (C-RNTI) of the first terminal, the N3C interface identifier of the first terminal, the mapping relationship between the signaling radio bearer (remote UE SRB, such as SRB0 / 1 / 2) of the first terminal and the radio link control channel (relay UE Uu RLC channel) on the radio interface of the target terminal, and the configuration information of the radio link control channel on the radio interface of the target terminal. Among them, the N3C interface is an interface for communication between the control plane and the user plane.

[0139] In some embodiments, the first terminal may also report its own N3C interface to the source access network device.

[0140] S304: The target access network device sends a switching request response to the source access network device.

[0141] The detailed description of step S304 may refer to the description of step S102 above.

[0142] Exemplarily, the target access network device receives the switching request message and may perform access control on the first terminal to determine whether to allow it to access the network, that is, whether to allow the first terminal to switch from the source access network device to the target access network device.

[0143] In the case where the target access network device allows the first terminal to switch, if the target access network device and the target terminal are both ready for switching, the target access network device can send a switching request response to the source access network device. Exemplarily, in the case where the Relay UE first switches to the target access network device and then the Remote UE switches to the target access network device, the first indication information in the switching request response may include indication information for agreeing to maintain data transmission on a direct path and indication information for disagreeing to maintain data transmission on an indirect path. In addition, the first indication information may also include an identifier of the target terminal, such as the C-RNTI / N3C interface identifier / F1AP UE ID of the target Relay UE. At this point, the first terminal is configured to stop data transmission on the second path, and / or the second terminal has been configured to switch to the target access network device.

[0144] In some embodiments, the first indication information is indication information with a terminal as the granularity, or indication information with a data radio bearer as the granularity, that is, the first indication information may be configured per UE or per DRB.

[0145] S305. The source access network device sends second indication information to the first terminal.

[0146] The detailed description of step S304 may refer to the description of step S102 above.

[0147] In some embodiments, the source access network device may send handover-related configuration information (i.e., second indication information) to the first terminal through an RRC reconfiguration message, including at least one of target cell information and indication information for maintaining direct path connectivity during the handover process. In this embodiment, the second indication information may also include an identifier of the target terminal, such as a C-RNTI of the target terminal, a serving cell identifier of the target terminal, etc.

[0148] At this time, the second indication information can be specifically used to instruct the first terminal to maintain data transmission on the first path and connect to the target access network device through a fourth path, where the fourth path is the path through which the first terminal connects to the target access network device through the target terminal.

[0149] In some embodiments, the first terminal may further maintain independent security contexts and robust header compression (ROHC) contexts for data transmission over the second path and the third path, respectively, and maintain a common packet data convergence protocol (PDCP) sequence number allocation.

[0150] Exemplarily, after receiving the second indication information, the first terminal may continue data transmission of the direct path (first path) of the source access network device (if indication information of retaining the direct path is received). During the handover execution, the first terminal may maintain separate security contexts and ROHC header compressor contexts for uplink transmissions to the source access network device and the target access network device, respectively; the UE maintains a common uplink PDCP SN allocation. In addition, the first terminal uses the security context and ROHC header decompression function associated with the source access network device / target access network device to receive downlink data sent by the source access network device / target access network device, respectively, while maintaining the general functions of reordering, duplicate detection and discarding, and transmitting the PDCP SDU to the upper layer in sequence.

[0151] S306. The first terminal sends an RRC reconfiguration completion message to the target access network device.

[0152] Exemplarily, after the first terminal successfully accesses the target access network device, an RRC reconfiguration completion message can be sent to the target access network device through the target terminal.

[0153] In some embodiments, the uplink data of the first terminal may also be switched from being transmitted to a source access network device to being transmitted to a target access network device.

[0154] Exemplarily, the target terminal can forward the signaling of the first terminal to the target access network device according to the mapping relationship between the configured SRB of the first terminal and the Uu RLC channel. When the target terminal successfully sends the RRC reconfiguration completion message of the first terminal to the target access network device (for example, receiving the RLC ack fed back by the target access network device), the target terminal notifies the first terminal through the N3C interface, and the first terminal stops sending uplink data to the source access network device. Thus, the first terminal transfers the uplink data to the target access network device through the target terminal.

[0155] S307: The target access network device sends a switching success indication message to the source access network device.

[0156] Exemplarily, after the target access network device receives the RRC reconfiguration completion message from the first terminal, it may send switching success indication information to the source access network device.

[0157] The detailed description of step S307 may refer to the description of step S206 above, which will not be repeated here.

[0158] based on Figure 8In the embodiment shown, the Relay UE is first switched to the target access network device, and then the Remote UE is switched to the target access network device, and during the switching process, the data transmission of the first path is maintained, and the target access network device is connected through the fourth path. In this way, the network interruption time of the terminal can be reduced, so that service continuity can be maintained when switching across access network devices.

[0159] In the case where the Relay UE is first switched to the target access network device and then the Remote UE is switched to the target access network device, such as Fig. 9 As shown, the present disclosure also provides another switching method, including:

[0160] S401. The first terminal sends a measurement report to a source access network device.

[0161] Exemplarily, the connection between the first terminal and the source access network device can refer to Figure 2 The examples shown are not repeated here. In the process of the first terminal and its aggregated terminal (second terminal) gradually moving away from the source access network device to the target access network device, if the first terminal or the second terminal triggers a measurement report, the first terminal or the second terminal can perform a measurement and send the obtained measurement report to the source access network device. The measurement report may include the measurement results of the serving cell, the measurement results of the candidate cell, etc. Furthermore, after receiving the measurement report, the source access network device can determine whether to switch the terminal (the first terminal and the second terminal).

[0162] S402: The source access network device sends a switching request message to the target access network device.

[0163] For a detailed description of step S402, reference may be made to the description of step S101 above.

[0164] Exemplarily, when the Relay UE (second terminal) first switches to the target access network device, the source access network device determines to send a handover message to the first terminal, and can send a handover request message to the target access network device. In some embodiments, before executing step S402, the source access network device can send a third indication information to the second device, and the third indication information is used to instruct the second terminal to switch to the target access network device.

[0165] During the switching of the second terminal, the first terminal can transmit data to the source access network device through a direct path. Before configuring the second terminal to switch, the source access network device can also configure the first terminal to release the split bearer (Split Bearer) and the indirect bearer (Indirect Bearer) transmitted through the indirect path, so that the corresponding service data can be configured to use the Uu bearer on the direct path to transmit data.

[0166] In some embodiments, the handover request message includes at least one of the following:

[0167] The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device (for example, F1AP UE ID), the identifier of the target terminal (for example, F1AP UE ID), the wireless network temporary identifier (C-RNTI) of the target terminal, and indication information for maintaining data transmission on an indirect path during the switching process.

[0168] Exemplarily, the Relay UE first switches to the target access network device (the second path has ended data transmission). When the source access network device decides to initiate a handover of the first terminal, if the source access network device wishes to stop the direct path (first path) on the source access network device side for data transmission during the handover of the first terminal, data transmission is performed with the source access network device side through an indirect path (fifth path), and connected to the target access network device through a direct path (third path), such as Figure 6 The fifth path is a path for the first terminal to be indirectly connected to the source access network device via the target terminal and the target access network device.

[0169] In some embodiments, the information in the above-mentioned handover request message (indication information on whether to retain the path on the device side of the source access network) is indication information with terminal granularity, or indication information with data radio bearer granularity. That is, the indication information on whether to retain the path on the device side of the source access network can be configured per UE or per DRB.

[0170] S403: The target access network device sends an RRC reconfiguration message to the target terminal.

[0171] In the case where the target access network device allows the first terminal to switch, the target access network device may accept the first terminal to connect to itself through the target terminal (indicated by the source access network device), or the target access device itself may select a target terminal for the first terminal from the candidate aggregation terminals. The target terminal includes the aggregation terminal that has been switched to the target access network device, and the target terminal may also be the second terminal or other possible terminals.

[0172] It should be understood that Fig. 9 The technical solution of the embodiment of the present disclosure is exemplarily described by taking the target terminal as the second terminal, and the target terminal may also be other possible aggregation terminals that have been switched to the target access network device.

[0173] In some embodiments, the RRC reconfiguration message includes at least one of the following:

[0174] The radio network temporary identifier (C-RNTI) of the first terminal, the N3C interface identifier of the first terminal, the mapping relationship between the signaling radio bearer (remote UE SRB, such as SRB0 / 1 / 2) of the first terminal and the radio link control channel (relay UE Uu RLC channel) on the radio interface of the target terminal, and the configuration information of the radio link control channel on the radio interface of the target terminal. Among them, the N3C interface is an interface for communication between the control plane and the user plane.

[0175] In some embodiments, the first terminal may also report its own N3C interface to the source access network device.

[0176] S404: The target access network device sends a switching request response to the source access network device.

[0177] The detailed description of step S404 may refer to the description of step S102 above.

[0178] Exemplarily, the target access network device receives the switching request message and may perform access control on the first terminal to determine whether to allow it to access the network, that is, whether to allow the first terminal to switch from the source access network device to the target access network device.

[0179] Exemplarily, in the case where the target access network device allows the first terminal to switch, if the target access network device and the target terminal are both ready for switching, the target access network device may send a switching request response to the source access network device.

[0180] In this embodiment, when the Relay UE is first switched to the target access network device and then the Remote UE is switched to the target access network device, the first indication information in the handover request response may include indication information of not agreeing to maintain data transmission of the direct path and indication information of agreeing to maintain data transmission of the indirect path. In addition, the first indication information may also include an identifier of the target terminal, such as the C-RNTI / N3C interface identifier / F1AP UE ID of the target Relay UE.

[0181] In some embodiments, the first indication information is indication information with a terminal as the granularity, or indication information with a data radio bearer as the granularity, that is, the first indication information may be configured per UE or per DRB.

[0182] In some embodiments, the indirect path between the target access network device and the source access network device can establish a data channel for forwarding the first terminal data, that is, a tunnel (tunnel) of an Xn interface for forwarding the data of the first terminal on the indirect path can be established through negotiation. The uplink data on the indirect path of the first terminal is forwarded by the target base station to the source base station through the Xn tunnel, and the downlink data on the indirect path of the first terminal is forwarded by the source base station to the target base station through the Xn tunnel.

[0183] S405. The source access network device sends second indication information to the first terminal.

[0184] For a detailed description of step S504, reference may be made to the description of step S102 above.

[0185] In some embodiments, the source access network device may send the handover-related configuration information (i.e., the second indication information) to the first terminal through an RRC reconfiguration message, including at least one of the target cell information and the indication information for maintaining indirect path connectivity during the handover process. In this embodiment, the second indication information may also include an identifier of the target terminal, such as the C-RNTI of the target terminal, the serving cell identifier of the target terminal, etc.

[0186] At this time, the second indication information can be specifically used to instruct the first terminal to stop data transmission on the first path and maintain data transmission with the source access network device through the fifth path. The fifth path is a path in which the first terminal is indirectly connected to the source access network device through the target terminal and the target access network device, and is connected to the target access network device through the third path.

[0187] Exemplarily, the first terminal receives the second indication information and can stop sending and receiving data on the Uu port with the source access network device. If the first terminal receives the indication information to retain the indirect path, the first terminal can continue to send and receive data on the N3C indirect path during the handover execution. At this time, the UL data transmission path is: first terminal->target terminal->target access network device->source access network device->UPF; DL data transmission path: 1) UPF->source access network device->target access network device->target terminal->first terminal.

[0188] In some embodiments, the first terminal may further maintain independent security contexts and robust header compression (ROHC) contexts for data transmission over the second path and the third path, respectively, and maintain a common packet data convergence protocol (PDCP) sequence number allocation.

[0189] Exemplarily, after receiving the second indication information, the first terminal can transmit data through the indirect path (fifth path) of the source access network device (when the indication information of retaining the indirect path is received). During the handover execution, the first terminal can maintain separate security contexts and ROHC header compressor contexts for uplink transmissions to the source access network device and the target access network device, respectively; the UE maintains a common uplink PDCP SN allocation. In addition, the first terminal uses the security context and ROHC header decompression function associated with the source access network device / target access network device to receive the downlink data sent by the source access network device / target access network device, respectively, while maintaining the general functions of reordering, duplicate detection and discarding, and transmitting the PDCP SDU to the upper layer in sequence.

[0190] S406. The first terminal sends an RRC reconfiguration completion message to the target access network device.

[0191] Exemplarily, after the first terminal successfully accesses the target access network device, an RRC reconfiguration completion message can be sent to the target access network device through the target terminal.

[0192] In some embodiments, the uplink data of the first terminal may also be switched from being transmitted to a source access network device to being transmitted to a target access network device.

[0193] Exemplarily, the first terminal no longer sends uplink data through the indirect path (fifth path) on the source access network device side, and the uplink data transmission is transferred to the target access network device. When the uplink data of the first terminal is transferred from the source access network device to the target access network device, lossless transmission of the uplink data needs to be considered. Under UE aggregation, it can be assumed that the first terminal can determine which data packets have been successfully / unsuccessfully sent to the target access network device by the target terminal (for example, RLC ack / nack received from the Uu port) based on the N3C ideal interface. Then, when the first terminal transfers the uplink data transmission to the target access network device (using the security context and ROHC header compression configuration associated with the target access network device), it can start from the first data packet that has not been confirmed received by gNB2RLC on the introduction path and transmit it to the target access network device (through the direct Uu link between the target access network device).

[0194] Among them, usually the data packet confirmed received by the target access network device RLC on the indirect path (fifth path) needs to be further forwarded to the source access network device, and the source access network device needs to determine the time when the data forwarding of the target access network device is completed. In the embodiment of the present disclosure, the source access network device no longer needs to wait for the data packet of the first terminal forwarded by the target access network device. The first terminal can transmit an end marker indication on the indirect path (fifth path) (or send an end marker for each bearer on the indirect path) when preparing to transfer the uplink data transmission from the source access network device to the target access network device. Then, when the source access network device receives the end marker forwarded on the indirect path (fifth path) (or receives the end markers of all bearers on the indirect path), it can be determined that the data forwarding of the target access network device is completed / no need to wait for the uplink data packet of the first terminal forwarded by the target access network device.

[0195] S407: The target access network device sends a switching success indication message to the source access network device.

[0196] Exemplarily, after the target access network device receives the RRC reconfiguration completion message from the first terminal, it may send switching success indication information to the source access network device.

[0197] Furthermore, after receiving the switching success indication information, the source access network device can stop sending downlink data on the indirect path (fifth path) on the source access network device side, receive downlink data from the UPF and forward it to the target access network device. In addition, the source access network device stops sending uplink data packets of the first terminal to the UPF, but forwards the uplink data packets to the target access network device.

[0198] In some embodiments, the source access network device sends a sequence number (SN) state transfer to the target access network device.

[0199] When the transmission paths of the uplink and downlink data of the first terminal are switched, the target access network device may send an RRC reconfiguration message to the first terminal to instruct the first terminal to release the relevant configurations on the source access network device side (such as the security context associated with the source access network device, ROHC header compression, and other configurations). For example, it may include an indirect path release indication on the source access network device side, a direct path release indication on the source access network device side, and reconfiguration of the bearer.

[0200] In some embodiments, for the aggregated terminal (second terminal) on the indirect path on the source access network device side, the second terminal can continue to forward the uplink and downlink data of the first terminal until the Uu RLC channel is released, or the indication information of releasing the first terminal sent by the source access network device is received. The target access network device can also update / reconfigure the mapping relationship between the UuRLC channel and the remote UE RB and the Uu RLC channel for the target terminal.

[0201] based on Fig. 9 In the embodiment shown, the Relay UE is first switched to the target access network device, and then the Remote UE is switched to the target access network device, and during the switching process, data is transmitted with the source access network device through the fifth path, and the Remote UE is connected with the target access network device through the third path. In this way, the network interruption time of the terminal can be reduced, so that service continuity can be maintained when switching across access network devices.

[0202] The above mainly introduces the solution provided by the present disclosure from the perspective of interaction between various communication nodes. It is understandable that, in order to realize the above functions, each communication node includes a hardware structure and / or software module corresponding to the execution of each function. It should be easily appreciated by those skilled in the art that, in combination with the algorithm steps of each example described in the embodiments disclosed herein, the present disclosure can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present disclosure.

[0203] Fig.10 FIG. 1 is a schematic diagram of the composition of a communication device provided in an embodiment of the present disclosure. The communication device 1000 can execute the switching method performed by the source access network device provided in the above method embodiment. Fig.10 As shown, the communication device 1000 includes a sending module 1001 and a receiving module 1002 .

[0204] The sending module 1001 is used to send a switching request message to a target access network device, and the switching request information is used to request to switch the first terminal to the target access network device; wherein the first terminal is connected to the source access network device through a first path and a second path, the first path is a direct path between the first terminal and the source access network device, and the second path is an indirect path connecting the first terminal to the source access network device through the second terminal.

[0205] The receiving module 1002 is used to receive a handover request response from a target access network device.

[0206] In some embodiments, the handover request message is further used to request to maintain data transmission on a direct path during the handover process, and / or to maintain data transmission on an indirect path during the handover process.

[0207] In some embodiments, the handover request response includes first indication information, where the first indication information is used to indicate whether to agree to maintain data transmission on a direct path and / or whether to agree to maintain data transmission on an indirect path during the handover process.

[0208] In some embodiments, the sending module 1001 is further used to send second indication information to the first terminal, the second indication information is used to instruct the first terminal to switch to the target access network device, and to keep the first terminal connected to the source access network device during the switching process. The receiving module 1002 is further used to receive indication information of successful switching of the first terminal from the target access network device.

[0209] In some embodiments, the second indication information includes at least one of the following: target cell information, indication information of whether to maintain direct path connectivity during the handover process, and indication information of whether to maintain indirect path connectivity.

[0210] In some embodiments, the second indication information is specifically used to instruct the first terminal to stop data transmission on the first path and maintain data transmission on the second path, and connect to the target access network device through a third path, where the third path is a path directly connecting the first terminal and the target access network device.

[0211] In some embodiments, before sending a switching request message to the target access network device, the sending module 1001 is further used to send third indication information to the second device, where the third indication information is used to instruct the second terminal to switch to the target access network device.

[0212] In some embodiments, the second indication information further includes an identifier of a target terminal, where the target terminal includes an aggregation terminal that has been switched to a target access network device.

[0213] In some embodiments, the handover request message includes at least one of the following:

[0214] The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device, the identifier of the target terminal, the wireless network temporary identifier of the target terminal, and indication information for maintaining data transmission on a direct path during the switching process.

[0215] In some embodiments, the second indication information is specifically used to instruct the first terminal to maintain data transmission on the first path and to connect to the target access network device through a fourth path, where the fourth path is the path where the first terminal connects to the target access network device through the target terminal.

[0216] In some embodiments, the handover request message includes at least one of the following:

[0217] The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device, the identifier of the target terminal, the wireless network temporary identifier of the target terminal, and indication information for maintaining data transmission on an indirect path during the switching process.

[0218] In some embodiments, the second indication information is specifically used to instruct the first terminal to stop data transmission on the first path and maintain data transmission with the source access network device through a fifth path, the fifth path being a path through which the first terminal is indirectly connected to the source access network device via the target terminal and the target access network device, and is connected to the target access network device via a third path.

[0219] In some embodiments, the information in the handover request message, the first indication information and the second indication information in the handover request response are indication information with a terminal as the granularity or indication information with a data radio bearer as the granularity.

[0220] For a more detailed description of the sending module 1001 and the receiving module 1002, as well as a more detailed description of each technical feature therein and a description of the beneficial effects, etc., please refer to the corresponding method embodiment section above, which will not be repeated here.

[0221] Fig.11 FIG. 1 is a schematic diagram of a communication device provided in an embodiment of the present disclosure. The communication device 1100 can execute the switching method performed by the target access network device provided in the above method embodiment. Fig.11 As shown, the communication device 1100 includes a receiving module 1101 and a sending module 1102 .

[0222] The receiving module 1101 is used to receive switching request information from a source access network device, and the switching request information is used to request to switch the first terminal to a target access network device; wherein the first terminal is connected to the source access network device via a first path and a second path, the first path is a direct path between the first terminal and the source access network device, and the second path is an indirect path connecting the first terminal to the source access network device via the second terminal.

[0223] The sending module 1102 is used to send a switching request response to the source access network device, where the switching request response includes second indication information, and the second indication information is used to indicate whether to agree to maintain direct path connectivity and / or whether to agree to maintain indirect path connectivity during the switching process.

[0224] In some embodiments, the handover request message is further used to request to maintain data transmission on a direct path during the handover process, and / or to maintain data transmission on an indirect path during the handover process.

[0225] In some embodiments, the handover request response includes first indication information, where the first indication information is used to indicate whether to agree to maintain data transmission on a direct path and / or whether to agree to maintain data transmission on an indirect path during the handover process.

[0226] In some embodiments, the handover request message includes at least one of the following:

[0227] The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device, the identifier of the target terminal, the wireless network temporary identifier of the target terminal, and indication information for maintaining data transmission on a direct path or an indirect path during the switching process; wherein the target terminal includes the aggregation terminal that has been switched to the target access network device.

[0228] In some embodiments, the sending module 1102 is further used to send a radio resource control connection RRC reconfiguration message to the target terminal.

[0229] In some embodiments, the RRC reconfiguration message includes at least one of the following:

[0230] The wireless network temporary identifier of the first terminal, the N3C interface identifier of the first terminal, the mapping relationship between the signaling wireless bearer of the first terminal and the wireless link control channel on the wireless interface of the target terminal, and the configuration information of the wireless link control channel on the wireless interface of the target terminal.

[0231] In some embodiments, when the RRC reconfiguration of the first terminal is completed, the sending module 1102 is further used to send a switching success indication information to the source access network device.

[0232] For a more detailed description of the above-mentioned receiving module 1101 and sending module 1102, a more detailed description of each technical feature therein, and a description of the beneficial effects, etc., please refer to the above-mentioned corresponding method embodiment part, which will not be repeated here.

[0233] Fig.12FIG. 1 is a schematic diagram of a communication device provided in an embodiment of the present disclosure. The communication device 1200 can execute the switching method performed by the first terminal provided in the above method embodiment. Fig.12 As shown, the communication device 1200 includes a receiving module 1201 and a processing module 1202 .

[0234] The receiving module 1201 is used to receive second indication information from a source access network device, where the second indication information is used to instruct the first terminal to switch to a target access network device, and to maintain at least one path connection between the first terminal and the source access network device during the switching process;

[0235] The processing module 1202 is used to establish a connection with the target access network device based on the second indication information.

[0236] In some embodiments, the first terminal is connected to the source access network device through a first path and a second path; wherein the first path is a direct path between the first terminal and the source access network device; and the second path is an indirect path connecting the first terminal to the source access network device through the second terminal.

[0237] In some embodiments, the second indication information includes at least one of the following: target cell information, indication information of whether to maintain direct path connectivity during the switching process, and indication information of whether to maintain indirect path connectivity.

[0238] In some embodiments, the second indication information is indication information with a terminal as the granularity; or, the second indication information is indication information with a data radio bearer as the granularity.

[0239] In some embodiments, the processing module 1202 is specifically used to stop data transmission on the first path and maintain data transmission on the second path when the second indication information includes indication information for maintaining connectivity of the indirect path; and connect to the target access network device through a third path, where the third path is a direct path between the first terminal and the target access network device.

[0240] In some embodiments, the processing module 1202 is further configured to maintain independent security contexts and Robust Header Compression (ROHC) contexts for data transmission on the second path and the third path, respectively, and maintain a common Packet Data Convergence Protocol (PDCP) sequence number allocation.

[0241] In some embodiments, the processing module 1202 is further configured to switch the uplink data of the first terminal from being transmitted to the source access network device to being transmitted to the target access network device when the first terminal is connected to the target access network device through a third path.

[0242] In some embodiments, the first terminal is configured to stop data transmission on the second path, and / or the second terminal is configured to switch to the target access network device.

[0243] In some embodiments, the second indication information further includes identification information of the target terminal, and the target terminal includes an aggregation terminal that has been switched to the target access network device.

[0244] In some embodiments, the processing module 1202 is specifically used to maintain data transmission on the first path when the second indication information includes indication information for maintaining direct path connectivity; and connect to the target access network device through a fourth path, where the fourth path is a path for connecting the first terminal to the target access network device through the target terminal.

[0245] In some embodiments, the processing module 1202 is specifically used to stop data transmission on the first path and maintain data transmission with the source access network device through a fifth path when the second indication information includes indication information for maintaining connectivity of the indirect path, the fifth path being a path where the first terminal is indirectly connected to the source access network device through the target terminal and the target access network device; and connected to the target access network device through a third path.

[0246] For a more detailed description of the above-mentioned receiving module 1201 and processing module 1202, a more detailed description of each technical feature therein, and a description of the beneficial effects, etc., please refer to the above-mentioned corresponding method embodiment part, which will not be repeated here.

[0247] Fig.13 FIG. 1 is a schematic diagram of a communication device provided in an embodiment of the present disclosure. The communication device 1300 can execute the switching method performed by the second terminal provided in the above method embodiment. Fig.13 As shown, the communication device 1300 includes a processing module 1301 and a receiving module 1302 .

[0248] Processing module 1301 is used to maintain data transmission on an indirect path between the first terminal and the source access network device during the process of the first terminal switching from the source access network device to the target access network device, or to maintain data transmission on an indirect path between the first terminal and the target access network device.

[0249] In some embodiments, the processing module 1301 is used to maintain data transmission of the first terminal through the indirect path between the second terminal and the source access network device when the second terminal has not switched to the target access network device.

[0250] In some embodiments, the receiving module 1302 is further used to receive indication information from the source access network device for instructing the second terminal to switch to the target access network device when the first terminal has switched to the target access network device.

[0251] In some embodiments, processing module 1301 is used to maintain data transmission on the path connecting the first terminal to the target access network device through the second terminal when the second terminal has switched to the target access network device; or to maintain data transmission on the path connecting the first terminal to the source access network device through the second terminal and the target access network device.

[0252] In some embodiments, before maintaining data transmission on the indirect path between the first terminal and the target access network device, the receiving module 1302 is further configured to receive an RRC reconfiguration message from the target access network device.

[0253] In some embodiments, the RRC reconfiguration message includes at least one of the following:

[0254] The wireless network temporary identifier of the first terminal, the N3C interface identifier of the first terminal, the mapping relationship between the signaling wireless bearer of the first terminal and the wireless link control channel on the wireless interface of the target terminal, and the configuration information of the wireless link control channel on the wireless interface of the target terminal.

[0255] For a more detailed description of the processing module 1301 and the receiving module 1302, as well as a more detailed description of each technical feature therein and a description of the beneficial effects, etc., please refer to the corresponding method embodiment part above, which will not be repeated here.

[0256] It should be noted that Figure 10-13 The modules in the example may also be referred to as units. For example, the sending module may be referred to as a sending unit. Figure 10-13 In the illustrated embodiment, the names of the modules may not be the names shown in the figure. For example, the receiving module may be called a communication module, and the sending module may be called a communication module.

[0257] Figure 10-13If the various units or modules in the embodiment are implemented in the form of software function modules 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 the embodiment of the present disclosure is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor (processor) to perform all or part of the steps of the various embodiments of the present disclosure. The storage medium for storing computer software products includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program codes.

[0258] In the case of implementing the functions of the above-mentioned integrated modules in the form of hardware, the present disclosure provides a schematic diagram of the structure of a communication device, which may be the above-mentioned Figure 10-13 Any communication device. Fig.14 As shown, the communication device 1400 includes: a processor 1402 , a communication interface 1403 , and a bus 1404 . Optionally, the communication device 1400 may further include a memory 1401 .

[0259] The processor 1402 may be a processor that implements or executes various exemplary logic blocks, modules, and circuits described in conjunction with the contents of the present disclosure. The processor 1402 may be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with the contents of the present disclosure. The processor 1402 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, and the like.

[0260] The communication interface 1403 is used to connect with other devices via a communication network, such as Ethernet, wireless access network, wireless local area network (WLAN), etc.

[0261] The memory 1401 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto.

[0262] As a possible implementation, the memory 1401 may exist independently of the processor 1402, and the memory 1401 may be connected to the processor 1402 via a bus 1404 to store instructions or program codes. When the processor 1402 calls and executes the instructions or program codes stored in the memory 1401, the method provided in the embodiment of the present disclosure can be implemented.

[0263] In another possible implementation, the memory 1401 may also be integrated with the processor 1402 .

[0264] The bus 1404 may be an extended industry standard architecture (EISA) bus, etc. The bus 1404 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig.14 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0265] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the equipment or device is divided into different functional modules to complete all or part of the functions described above.

[0266] The embodiment of the present disclosure also provides a computer-readable storage medium. All or part of the processes in the above method embodiments can be completed by computer instructions to instruct the relevant hardware, and the program can be stored in the above computer-readable storage medium. When the program is executed, it can include the processes of the above method embodiments. The computer-readable storage medium can be the memory or memory of any of the above embodiments. The above computer-readable storage medium can also be an external storage device of the above device or apparatus, such as a plug-in hard disk, a smart memory card (smart media card, SMC), a secure digital (secure digital, SD) card, a flash card (flash card), etc. equipped on the above device or apparatus. Further, the above computer-readable storage medium can also include both the internal storage unit of the above device or apparatus and an external storage device. The above computer-readable storage medium is used to store the above computer program and other programs and data required by the above device or apparatus. The above computer-readable storage medium can also be used to temporarily store data that has been output or is to be output.

[0267] The embodiments of the present disclosure also provide a computer program product, which includes a computer program. When the computer program product is run on a computer, the computer is enabled to execute any one of the methods provided in the above embodiments.

[0268] Although the present disclosure is described herein in conjunction with various embodiments, in the process of implementing the present disclosure as claimed, those skilled in the art may understand and implement other variations of the disclosed embodiments by reviewing the drawings, the disclosure, and the appended claims.

[0269] The word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality of components. A single processor or other unit can implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0270] Although the present disclosure has been described in conjunction with specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present disclosure. Accordingly, this specification and the drawings are merely exemplary illustrations of the present disclosure as defined by the appended claims, and are deemed to have covered any and all modifications, variations, combinations or equivalents within the scope of the present disclosure. Obviously, those skilled in the art may make various modifications and variations to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is also intended to include these modifications and variations.

[0271] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A switching method, characterized in that: Applied to a source access network device, the method comprises: Sending a switching request message to a target access network device, wherein the switching request message is used to request that a first terminal be switched to the target access network device; wherein the first terminal is connected to the source access network device through a first path and a second path, wherein the first path is a direct path between the first terminal and the source access network device, and the second path is an indirect path between the first terminal and the source access network device through a second terminal; A handover request response is received from the target access network device.

2. The method according to claim 1, characterized in that The handover request message is also used to request to maintain data transmission on a direct path during the handover process, and / or to maintain data transmission on an indirect path during the handover process.

3. The method according to claim 1, characterized in that The handover request response includes first indication information, where the first indication information is used to indicate whether to agree to maintain data transmission on a direct path and / or whether to agree to maintain data transmission on an indirect path during the handover process.

4. The method according to claim 1, characterized in that: The method further comprises: Sending second indication information to the first terminal, where the second indication information is used to instruct the first terminal to switch to the target access network device and to keep the first terminal connected to the source access network device during the switching process; Receive indication information that the first terminal has successfully switched from the target access network device.

5. The method according to claim 4, characterized in that The second indication information includes at least one of the following: target cell information, indication information of whether to maintain direct path connectivity during the switching process, and indication information of whether to maintain indirect path connectivity.

6. The method according to claim 5, characterized in that The second indication information is specifically used to instruct the first terminal to stop data transmission on the first path and maintain data transmission on the second path, and to connect to the target access network device via a third path, where the third path is a path that directly connects the first terminal to the target access network device.

7. The method according to claim 1, characterized in that Before sending the switching request message to the target access network device, the method further includes: Send third indication information to the second device, where the third indication information is used to instruct the second terminal to switch to the target access network device.

8. The method according to claim 7, characterized in that The second indication information further includes an identifier of a target terminal, where the target terminal includes an aggregation terminal that has been switched to the target access network device.

9. The method according to claim 7, characterized in that: The handover request message includes at least one of the following: The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device, the identifier of the target terminal, the wireless network temporary identifier of the target terminal, and indication information for maintaining data transmission on a direct path during the switching process.

10. The method according to claim 9, characterized in that The second indication information is specifically used to instruct the first terminal to maintain data transmission on the first path and to connect to the target access network device through a fourth path, where the fourth path is the path where the first terminal connects to the target access network device through the target terminal.

11. The method according to claim 7, characterized in that The handover request message includes at least one of the following: The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device, the identifier of the target terminal, the wireless network temporary identifier of the target terminal, and indication information for maintaining data transmission on an indirect path during the switching process.

12. The method according to claim 11, characterized in that The second indication information is specifically used to instruct the first terminal to stop data transmission on the first path and maintain data transmission with the source access network device through a fifth path, wherein the fifth path is a path for the first terminal to be indirectly connected to the source access network device through the target terminal and the target access network device, and to be connected to the target access network device through a third path, wherein the third path is a path for the first terminal to be directly connected to the target access network device.

13. The method according to claim 5, characterized in that At least one of the information in the switching request message, the first indication information in the switching request response, and the second indication information is indication information with a terminal as the granularity or indication information with a data radio bearer as the granularity.

14. A switching method, characterized in that: Applied to a target access network device, the method comprises: Receiving switching request information from a source access network device, the switching request information is used to request to switch a first terminal to the target access network device; wherein the first terminal is connected to the source access network device through a first path and a second path, the first path is a direct path between the first terminal and the source access network device, and the second path is an indirect path connecting the first terminal to the source access network device through a second terminal; Send a handover request response to the source access network device.

15. The method according to claim 14, characterized in that The handover request message is also used to request to maintain data transmission on a direct path during the handover process, and / or to maintain data transmission on an indirect path during the handover process.

16. The method according to claim 14, characterized in that The handover request response includes first indication information, where the first indication information is used to indicate whether to agree to maintain data transmission on a direct path and / or whether to agree to maintain data transmission on an indirect path during the handover process.

17. The method according to claim 14, characterized in that The handover request message includes at least one of the following: The wireless network temporary identifier of the candidate aggregation terminal, the service cell identifier of the candidate aggregation terminal, the association relationship between the first terminal and the aggregation terminal that has been switched to the target access network device, the association relationship between the first terminal and the second terminal, the identifier of the aggregation terminal that has been switched to the target access network device, the identifier of the target terminal, the wireless network temporary identifier of the target terminal, and indication information for maintaining data transmission on a direct path or an indirect path during the switching process; wherein the target terminal includes the aggregation terminal that has been switched to the target access network device.

18. The method according to claim 17, characterized in that The method further comprises: Send a radio resource control connection RRC reconfiguration message to the target terminal.

19. The method according to claim 18, characterized in that The RRC reconfiguration message includes at least one of the following: The wireless network temporary identifier of the first terminal, the N3C interface identifier of the first terminal, the mapping relationship between the signaling wireless bearer of the first terminal and the wireless link control channel on the wireless interface of the target terminal, and the configuration information of the wireless link control channel on the wireless interface of the target terminal.

20. The method according to claim 17, characterized in that In the case where the handover request message includes indication information of maintaining data transmission of the indirect path during the handover process, the method further includes: An indirect path with the source access network device establishes a data channel for forwarding the first terminal data.

21. The method according to claim 20, characterized in that The method further comprises: forwarding the uplink data of the first terminal to the source access network device through the data channel; and / or, The downlink data of the first terminal forwarded by the source access network device is received through the data channel.

22. The method according to claim 14, characterized in that The method further comprises: When the RRC reconfiguration of the first terminal is completed, a switching success indication message is sent to the source access network device.

23. A switching method, characterized in that: Applied to a first terminal, the method includes: receiving second indication information from a source access network device, where the second indication information is used to instruct the first terminal to switch to a target access network device, and to maintain at least one path connection between the first terminal and the source access network device during the switching process; Based on the second indication information, a connection is established with the target access network device.

24. The method according to claim 23, characterized in that The first terminal is connected to the source access network device through a first path and a second path; The first path is a direct path between the first terminal and the source access network device; The second path is an indirect path connecting the first terminal to the source access network device via the second terminal.

25. The method according to claim 24, characterized in that The second indication information includes at least one of the following: target cell information, indication information of whether to maintain direct path connectivity during the switching process, and indication information of whether to maintain indirect path connectivity.

26. The method according to claim 24, characterized in that The establishing a connection with the target access network device based on the second indication information includes: When the second indication information includes indication information for maintaining connectivity of the indirect path, stopping data transmission on the first path and maintaining data transmission on the second path; The first terminal is connected to the target access network device via a third path, where the third path is a direct path between the first terminal and the target access network device.

27. The method according to claim 26, characterized in that The method comprises: Independent security contexts and robust header compression (ROHC) contexts are maintained for data transmission along the second path and the third path, respectively, and a common packet data convergence protocol (PDCP) sequence number allocation is maintained.

28. The method according to claim 26, characterized in that The method further comprises: In case of connecting to the target access network device through the third path, uplink data of the first terminal is switched from being transmitted to the source access network device to being transmitted to the target access network device.

29. The method according to claim 24, characterized in that The first terminal is configured to stop data transmission on the second path, and / or the second terminal is configured to switch to the target access network device.

30. The method according to claim 29, characterized in that The second indication information further includes identification information of a target terminal, where the target terminal includes an aggregation terminal that has been switched to the target access network device.

31. The method according to claim 30, characterized in that The second path stops data transmission, and the switching to the target access network device based on the second indication information includes: When the second indication information includes indication information for maintaining connectivity of the direct path, maintaining data transmission along the first path; The first terminal is connected to the target access network device through a fourth path, and the fourth path is a path for connecting the first terminal to the target access network device through the target terminal.

32. The method according to claim 30, characterized in that The switching to the target access network device based on the second indication information includes: When the second indication information includes indication information for maintaining connectivity of the indirect path, stop data transmission on the first path, and maintain data transmission with the source access network device through a fifth path, where the fifth path is a path for indirect connection between the first terminal and the source access network device through the target terminal and the target access network device; Connect to the target access network device through a third path.

33. A switching method, characterized in that: Applied to the second terminal, the method includes: During the process of the first terminal switching from the source access network device to the target access network device, the data transmission on the indirect path between the first terminal and the source access network device is maintained, or the data transmission on the indirect path between the first terminal and the target access network device is maintained.

34. The method according to claim 33, characterized in that The data transmission maintaining the indirect path between the first terminal and the source access network device includes: In a case where the second terminal does not switch to the target access network device, data transmission of the first terminal through the indirect path between the second terminal and the source access network device is maintained.

35. The method according to claim 34, characterized in that The method further comprises: In a case where the first terminal has switched to the target access network device, indication information for instructing the second terminal to switch to the target access network device is received from the source access network device.

36. The method according to claim 34, characterized in that The data transmission of maintaining the indirect path between the first terminal and the target access network device includes: When the second terminal has switched to the target access network device, maintaining data transmission of the first terminal through the path connecting the second terminal to the target access network device; or, Maintain data transmission on the path where the first terminal is connected to the source access network device through the second terminal and the target access network device.

37. The method according to claim 36, characterized in that Before the data transmission of the indirect path between the first terminal and the target access network device is maintained, the method further includes: Receive an RRC reconfiguration message from the target access network device.

38. The method according to claim 37, characterized in that The RRC reconfiguration message includes at least one of the following: The wireless network temporary identifier of the first terminal, the N3C interface identifier of the first terminal, the mapping relationship between the signaling wireless bearer of the first terminal and the wireless link control channel on the wireless interface of the target terminal, and the configuration information of the wireless link control channel on the wireless interface of the target terminal.

39. A communication device, characterized in that: include: Memory and processor; Memory and processor coupling; The memory is used to store instructions executable by the processor; When the processor executes the instructions, the method according to any one of claims 1 to 38 is performed.

40. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and when the computer instructions are executed on a processor, the processor executes the method according to any one of claims 1 to 38.

41. A computer program product, characterized in that The computer program product comprises a computer program, which, when executed on a computer, causes the computer to execute the method according to any one of claims 1 to 38.

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