Communication method and communication apparatus

Abstract

The present application relates to the field of communications, and in particular, to a communication method and a communication apparatus. Cell handover enables a terminal to switch from one cell to another cell; however, cell handover may collide with other cell change modes, causing the terminal to fail to connect to a target cell. In embodiments of the present application, a core network device or an access network device sends to the terminal second information indicating cells for different handover modes. The terminal determines a handover mode, and then can select a second cell on the basis of the second information; if it is determined that path switching is to be performed in a first handover mode, the terminal can select the second cell from among cells supporting the first handover mode; and if it is determined that path switching is to be performed in a second handover mode, the terminal can select the second cell from among cells supporting the second handover mode. The terminal selects a cell change mode on the basis of the second information, so as to avoid the problem caused by collision between multiple cell change modes.

Description

Communication method and communication device

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on January 19, 2024, with application number 202410084724.2 and application name “Communication Method and Communication Device,” the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communications, and in particular to a communication method and a communication device. Background Art

[0003] A cell can be considered as providing a wireless signal coverage area identified by a physical cell identifier (PCI) or a cell global identifier (CGI). The coverage area of ​​each base station can be divided into one or more cells. A terminal can switch from one cell to another. The cell before the handover can be called the source cell or anchor cell, and the cell after the handover can be called the target cell.

[0004] Cell handover enables a terminal to switch from a cell with poor channel conditions to a cell with better channel conditions, providing users with better communication services. Besides cell handover, a terminal can also establish a connection to a target cell using other cell change methods. However, the target cell in a cell handover may conflict with the target cell in other cell change methods, preventing the terminal from connecting to the target cell. Summary of the Invention

[0005] The embodiments of the present application provide a communication method, a communication device, a communication system, a computer-readable storage medium, and a computer program product, which can avoid problems caused by conflicts between multiple cell change methods.

[0006] In a first aspect, an embodiment of the present application provides a communication method, the execution subject of the method may be a terminal or a chip applied to a terminal, and the following description is made taking the execution subject as an example. The method includes: receiving second information through a first path, the second information including a first set and / or a second set, the first set indicating cells supporting the first switching mode, and the second set indicating cells supporting the second switching mode; determining to switch the first path to a second path through the first switching mode or the second switching mode, the second path including a connection between the terminal and the second cell, wherein, when the first path is switched to the second path through the first switching mode, the second cell belongs to the cell indicated by the first set, or the second cell does not belong to the cell indicated by the second set; or, when the first path is switched to the second path through the second switching mode, the second cell belongs to the cell indicated by the second set, or the second cell does not belong to the cell indicated by the first set.

[0007] Different cells may be applicable to different switching methods, and the first set and / or the second set indicate cells corresponding to different switching methods. After determining the switching method, the terminal can select the second cell based on the second information. If it is determined that the path is switched through the first switching method, the second cell can be selected from cells that support the first switching method, or the second cell can be avoided from cells that support the second switching method. If it is determined that the path is switched through the second switching method, the second cell can be selected from cells that support the second switching method, or the second cell can be avoided from cells that support the first switching method. The terminal selects a cell change method based on the second information, which can avoid problems caused by conflicts between multiple cell change methods.

[0008] Optionally, before receiving the second information through the first path, the method further includes: sending first information through the first path, the first information indicating that the terminal supports multiple switching modes, and the multiple switching modes include a first switching mode and a second switching mode.

[0009] In various embodiments of the present application, "the first information indication terminal supports multiple switching modes, and the multiple switching modes include a first switching mode and a second switching mode" can be expressed as: the first information indication terminal supports the second switching mode, or the first information indication terminal can perform switching through the second switching mode.

[0010] Since there may be terminals in the network that do not support the second switching mode or multiple switching modes, the terminal can send first information to indicate that it supports the second switching mode or multiple switching modes, so that the network device can perform processing related to the second switching mode.

[0011] Optionally, before determining to switch the first path to the second path through the first switching mode or the second switching mode, the method further includes: receiving third information through the first path, where the third information indicates that the terminal is allowed to execute multiple switching modes.

[0012] In various embodiments of the present application, “the third information indicates that the terminal is allowed to execute multiple switching modes” can be expressed as: the third information indicates that the terminal is allowed to execute the second switching mode.

[0013] The third information is used to respond to the first information, clearly indicating that the terminal is allowed to execute multiple switching methods. If the terminal receives the third information, it can execute multiple switching methods; if the terminal does not receive the third information, it can switch the path according to the default switching method (such as a switching method based on cell switching), thereby avoiding problems caused by the switching method executed by the terminal not being supported by the network device.

[0014] Optionally, before receiving the second information through the first path, the method further includes: sending fourth information through the first path, where the fourth information instructs the terminal to start a mode of executing the second switching manner.

[0015] In various embodiments of the present application, “starting a mode for executing the second switching mode” may also be expressed as: executing path switching through the second switching mode, or activating the second switching mode.

[0016] In some cases, if the terminal determines that the network device supports multiple switching modes, the fourth information may be used to indicate the terminal's needs, so that the network device configures a set that meets the terminal's needs through the second information.

[0017] Optionally, the method also includes: if it is determined that the first path is switched to the second path through the second switching method, adjusting the signal quality value of the second cell from the first value to the second value, the first value is greater than or equal to the signal quality value corresponding to the first switching method, and the second value is less than the signal quality value corresponding to the first switching method; sending the second value through the first path.

[0018] In various embodiments of the present application, “the first value is greater than or equal to the signal quality value corresponding to the first switching mode, and the second value is less than the signal quality value corresponding to the first switching mode” can be expressed as: the first value is greater than the signal quality value corresponding to the first switching mode, and the second value is less than or equal to the signal quality value corresponding to the first switching mode.

[0019] In some cases, the first switching mode is triggered by a network device. To avoid triggering the first switching mode, the terminal can modify the signal quality value to prevent the network device from triggering the first switching mode. This embodiment meets the terminal's path switching requirements without modifying the triggering mechanism of the first switching mode, thereby improving the compatibility of the method.

[0020] Optionally, the method also includes: if it is determined that the first path is switched to the second path through the second switching method, the signal quality value of the second cell is sent through the first path, and the signal quality value of the second cell is less than the signal quality value corresponding to triggering the execution of the first switching method.

[0021] In some cases, the first switching mode is triggered by a network device. To avoid triggering the first switching mode, the terminal can send the signal quality value of the second cell through the first path, or the terminal can send the signal quality value of the second cell through the first path without performing signal measurement, and the signal quality value is lower than the signal quality value corresponding to the triggering execution of the first switching mode, so as to avoid the network device triggering the first switching mode. This embodiment meets the path switching requirements of the terminal without modifying the triggering mechanism of the first switching mode, thereby improving the compatibility of the method.

[0022] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the public land mobile network (PLMN) corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is not equivalent to the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

[0023] The terminal does not need to select a network when transferring from the PLMN corresponding to the first cell to an equivalent PLMN, but needs to select a network when transferring from the PLMN corresponding to the first cell to a non-equivalent PLMN. Therefore, configuring the first set as a cell set of equivalent PLMNs is beneficial to a switching method based on cell switching, and configuring the second set as a cell set of non-equivalent PLMNs is beneficial to a switching method based on dual connectivity.

[0024] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMNs of the first cell, the PLMNs in the second PLMN set are not equivalent to the PLMNs of the first cell, and the first cell is the cell corresponding to the first path.

[0025] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the equivalent PLMN, and needs to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the non-equivalent PLMN. Therefore, configuring the first set as an equivalent PLMN set is beneficial to the switching method based on cell switching, and configuring the second set as a non-equivalent PLMN set is beneficial to the switching method based on dual connection.

[0026] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

[0027] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the same PLMN. The terminal may need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to a different PLMN. Therefore, configuring the first set as a cell set of the same PLMN is beneficial to the switching method based on cell switching, and configuring the second set as a cell set of different PLMNs is beneficial to the switching method based on dual connection.

[0028] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

[0029] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the same PLMN. The terminal may need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to a different PLMN. Therefore, configuring the first set as the same PLMN set is beneficial to the switching method based on cell switching, and configuring the second set as different PLMN sets is beneficial to the switching method based on dual connection.

[0030] In a second aspect, an embodiment of the present application provides a communication method, wherein the execution subject of the method may be an access network device or a chip applied to the access network device. The following description is based on the execution subject being the access network device. The method comprises: receiving permission information from a core network device, the permission information indicating that the terminal is allowed to execute multiple switching modes, the multiple switching modes including a first switching mode and a second switching mode; or, the permission information indicating that the terminal is allowed to execute the second switching mode; and sending second information to the terminal based on the permission information, the second information including a first set and / or a second set, the first set indicating cells that support the first switching mode, and the second set indicating cells that support the second switching mode.

[0031] Different cells may be applicable to different switching methods, and the first set and / or the second set indicate cells corresponding to different switching methods. After determining the switching method, the terminal can select the second cell based on the second information. If it is determined that the path is switched through the first switching method, the second cell can be selected from cells that support the first switching method, or the second cell can be avoided from cells that support the second switching method. If it is determined that the path is switched through the second switching method, the second cell can be selected from cells that support the second switching method, or the second cell can be avoided from cells that support the first switching method. The terminal selects a cell change method based on the second information, which can avoid problems caused by conflicts between multiple cell change methods.

[0032] Optionally, before receiving the permission information from the core network device, the method further includes: receiving first information from the terminal, the first information indicating that the terminal supports multiple switching modes, the multiple switching modes including a first switching mode and a second switching mode; and sending the first information to the core network device.

[0033] Since there may be terminals in the network that do not support the second switching mode or multiple switching modes, the terminal can send first information to indicate that it supports the second switching mode or multiple switching modes, so that the network device can perform processing related to the second switching mode.

[0034] Optionally, the method further includes: sending third information to the terminal, where the third information indicates that the terminal is allowed to execute multiple switching modes, where the multiple switching modes include a first switching mode and a second switching mode.

[0035] The third information is used to respond to the first information, clearly indicating that the terminal is allowed to execute multiple switching methods. If the terminal receives the third information, it can execute multiple switching methods; if the terminal does not receive the third information, it can switch the path according to the default switching method (such as a switching method based on cell switching), thereby avoiding problems caused by the switching method executed by the terminal not being supported by the network device.

[0036] Optionally, before sending the second information to the terminal, the method also includes: receiving fourth information from the terminal, the fourth information instructing the terminal to start a mode for executing the second switching method; sending the second information to the terminal includes: sending the second information to the terminal according to the fourth information.

[0037] In some cases, if the terminal determines that the network device supports multiple switching modes, the fourth information may be used to indicate the terminal's needs, so that the network device configures a set that meets the terminal's needs through the second information.

[0038] Optionally, sending the second information to the terminal includes: sending the second information to the terminal via the first path, wherein the cell corresponding to the first path is the first cell; the permission information includes at least one of the following information: fifth information, indicating that the access network device does not execute the first switching method; sixth information, indicating that the access network device executes the second switching method; a first PLMN set, wherein the PLMN in the first PLMN set is not equivalent to the PLMN of the first cell; and seventh information, indicating that the priority of the first switching method is lower than the priority of the second switching method.

[0039] In some cases, the core network device does not want the access network device to execute the first switching mode. The core network device can instruct the access network device not to execute the first switching mode through one or more information in the permission information. For example, the access network device can instruct the terminal not to execute operations related to the first switching mode based on the permission information, or remove the cells in the first set that support the first switching mode, thereby avoiding the terminal from executing the first switching mode.

[0040] Optionally, the method further includes: sending eighth information to the core network device, where the eighth information indicates that the switching mode configuration of the terminal has been updated.

[0041] The eighth information is used to respond to the permission information so that the core network device can determine that the terminal has completed the update of the switching mode configuration.

[0042] Optionally, sending second information to the terminal includes: sending second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, and the PLMN corresponding to the cells in the second cell set is not equivalent to the PLMN of the first cell.

[0043] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the equivalent PLMN, and needs to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the non-equivalent PLMN. Therefore, configuring the first set as a cell set of equivalent PLMNs is beneficial to the switching method based on cell switching, and configuring the second set as a cell set of non-equivalent PLMNs is beneficial to the switching method based on dual connection.

[0044] Optionally, sending second information to the terminal includes: sending second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMN of the first cell, and the PLMNs in the second PLMN set are not equivalent to the PLMN of the first cell.

[0045] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the equivalent PLMN, and needs to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the non-equivalent PLMN. Therefore, configuring the first set as an equivalent PLMN set is beneficial to the switching method based on cell switching, and configuring the second set as a non-equivalent PLMN set is beneficial to the switching method based on dual connection.

[0046] Optionally, sending second information to the terminal includes: sending second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, and the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell.

[0047] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the same PLMN. The terminal may need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to a different PLMN. Therefore, configuring the first set as a cell set of the same PLMN is beneficial to the switching method based on cell switching, and configuring the second set as a cell set of different PLMNs is beneficial to the switching method based on dual connection.

[0048] Optionally, sending the second information to the terminal includes: sending the second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, and the PLMNs in the second PLMN set do not include the PLMN of the first cell.

[0049] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the same PLMN. The terminal may need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to a different PLMN. Therefore, configuring the first set as the same PLMN set is beneficial to the switching method based on cell switching, and configuring the second set as different PLMN sets is beneficial to the switching method based on dual connection.

[0050] On the third aspect, an embodiment of the present application provides a communication method, the execution subject of the method may be an access network device or a chip applied to the access network device, and the following description is made by taking the execution subject being an access network device as an example. The method includes: receiving permission information from a core network device, the permission information indicating that the terminal is allowed to execute multiple switching modes, the multiple switching modes including a first switching mode and a second switching mode; or, the permission information indicating that the terminal is allowed to execute the second switching mode; receiving fourth information from the terminal via a first path, the fourth information indicating that the terminal turns on a mode for executing the second switching mode; determining not to turn on a mode for executing the first switching mode based on the permission information and the fourth information; or, sending second information to the terminal via the first path; or, sending update information of the second information to the terminal via the first path; wherein the second information includes a first set and / or a second set, the first set indicating cells that support the first switching mode, and the second set indicating cells that support the second switching mode.

[0051] Different cells may be applicable to different switching methods, and the first set and / or the second set indicate cells corresponding to different switching methods. After determining the switching method, the terminal can select the second cell based on the second information. If it is determined that the path is switched through the first switching method, the second cell can be selected from cells that support the first switching method, or the second cell can be avoided from cells that support the second switching method. If it is determined that the path is switched through the second switching method, the second cell can be selected from cells that support the second switching method, or the second cell can be avoided from cells that support the first switching method. The terminal selects a cell change method based on the second information, which can avoid problems caused by conflicts between multiple cell change methods.

[0052] Optionally, before receiving the permission information from the core network device, the method also includes: receiving first information from the terminal through a first path, the first information indicating that the terminal supports multiple switching modes, the multiple switching modes including a first switching mode and a second switching mode; and sending the first information to the core network device.

[0053] Since there may be terminals in the network that do not support the second switching mode or multiple switching modes, the terminal can send first information to indicate that it supports the second switching mode or multiple switching modes, so that the network device can perform processing related to the second switching mode.

[0054] Optionally, the method further includes: sending third information to the terminal through the first path, where the third information indicates that the terminal is allowed to execute multiple switching modes.

[0055] The third information is used to respond to the first information, clearly indicating that the terminal is allowed to execute multiple switching methods. If the terminal receives the third information, it can execute multiple switching methods; if the terminal does not receive the third information, it can switch the path according to the default switching method (such as a switching method based on cell switching), thereby avoiding problems caused by the switching method executed by the terminal not being supported by the network device.

[0056] Optionally, the permission information includes at least one of the following information: fifth information, indicating that the access network device does not execute the first switching method; sixth information, indicating that the access network device executes the second switching method; a first PLMN set, wherein the PLMN in the first PLMN set is not equivalent to the PLMN of the first cell, and the first cell is the cell corresponding to the first path; seventh information, indicating that the priority of the first switching method is lower than the priority of the second switching method.

[0057] In some cases, the core network device does not want the access network device to execute the first switching mode. The core network device can instruct the access network device not to execute the first switching mode through one or more information in the permission information. For example, the access network device can instruct the terminal not to execute operations related to the first switching mode based on the permission information, or remove the cells in the first set that support the first switching mode, thereby avoiding the terminal from executing the first switching mode.

[0058] Optionally, the method further includes: sending eighth information to the core network device, where the eighth information indicates that the switching mode configuration of the terminal has been updated.

[0059] The eighth information is used to respond to the permission information so that the core network device can determine that the terminal has completed the update of the switching mode configuration.

[0060] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is not equivalent to the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

[0061] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the equivalent PLMN, and needs to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the non-equivalent PLMN. Therefore, configuring the first set as a cell set of equivalent PLMNs is beneficial to the switching method based on cell switching, and configuring the second set as a cell set of non-equivalent PLMNs is beneficial to the switching method based on dual connection.

[0062] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMNs of the first cell, the PLMNs in the second PLMN set are not equivalent to the PLMNs of the first cell, and the first cell is the cell corresponding to the first path.

[0063] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the equivalent PLMN, and needs to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the non-equivalent PLMN. Therefore, configuring the first set as an equivalent PLMN set is beneficial to the switching method based on cell switching, and configuring the second set as a non-equivalent PLMN set is beneficial to the switching method based on dual connection.

[0064] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

[0065] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the same PLMN. The terminal may need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to a different PLMN. Therefore, configuring the first set as a cell set of the same PLMN is beneficial to the switching method based on cell switching, and configuring the second set as a cell set of different PLMNs is beneficial to the switching method based on dual connection.

[0066] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

[0067] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the same PLMN. The terminal may need to perform network selection when transferring from the PLMN corresponding to the first cell to a different PLMN. Therefore, configuring the first set as the same PLMN set is beneficial to the switching method based on cell switching, and configuring the second set as different PLMN sets is beneficial to the switching method based on dual connection.

[0068] In a fourth aspect, embodiments of the present application provide a communication method, wherein the method may be performed by a core network device or a chip applied to the core network device. The following description uses the core network device as an example. The method includes: determining permission information, where the permission information indicates that a terminal is permitted to perform multiple switching modes, where the multiple switching modes include a first switching mode and a second switching mode; alternatively, the permission information indicates that the terminal is permitted to perform the second switching mode; and sending the permission information.

[0069] Different core network devices may apply different switching methods. If the core network device supports a new switching method (such as the second switching method), the core network device can instruct the terminal to execute multiple switching methods or the second switching method, thereby avoiding problems caused by incompatibility between the switching method determined by the terminal and the switching method supported by the core network device, and avoiding problems caused by conflicts between multiple cell change methods.

[0070] Optionally, before sending the permission information, the method further includes: receiving first information, where the first information indicates that the terminal supports multiple switching modes, and the multiple switching modes include a first switching mode and a second switching mode.

[0071] Since there may be terminals in the network that do not support the second switching mode or multiple switching modes, the terminal can send first information to indicate that it supports the second switching mode or multiple switching modes, so that the network device can perform processing related to the second switching mode.

[0072] Optionally, the permission information includes at least one of the following information: fifth information, indicating that the access network device does not execute the first switching method; sixth information, indicating that the access network device executes the second switching method; a first PLMN set, the PLMN in the first PLMN set is not equivalent to the PLMN of the first cell, the first cell is the cell corresponding to the first path, and the first path includes the connection between the terminal and the access network device; seventh information, indicating that the priority of the first switching method is lower than the priority of the second switching method.

[0073] In some cases, the core network device does not want the access network device to execute the first switching mode. The core network device can instruct the access network device not to execute the first switching mode through one or more information in the permission information. For example, the access network device can instruct the terminal not to execute operations related to the first switching mode based on the permission information, or remove the cells in the first set that support the first switching mode, thereby avoiding the terminal from executing the first switching mode.

[0074] Optionally, the permission information includes a first set and / or a second set, the first set indicates PLMNs supporting a first switching mode, and the second set indicates PLMNs supporting a second switching mode.

[0075] The core network device sends the first set and / or the second set through the permission information, which is beneficial for the access network device or the terminal to determine the cells corresponding to different switching modes.

[0076] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMNs of the first cell, the PLMNs in the second PLMN set are not equivalent to the PLMNs of the first cell, the first cell is the cell corresponding to the first path, and the first path includes the connection between the terminal and the access network device.

[0077] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the equivalent PLMN, and needs to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the non-equivalent PLMN. Therefore, configuring the first set as an equivalent PLMN set is beneficial to the switching method based on cell switching, and configuring the second set as a non-equivalent PLMN set is beneficial to the switching method based on dual connection.

[0078] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, the first cell is the cell corresponding to the first path, and the first path includes the connection between the terminal and the access network device.

[0079] The terminal does not need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to the same PLMN. The terminal may need to perform network selection when switching from the PLMN corresponding to the first cell to the cell corresponding to a different PLMN. Therefore, configuring the first set as a cell set of the same PLMN is beneficial to the switching method based on cell switching, and configuring the second set as a cell set of different PLMNs is beneficial to the switching method based on dual connection.

[0080] Optionally, the method further includes: receiving eighth information, where the eighth information indicates that the switching mode configuration of the terminal has been updated.

[0081] The eighth information is used to respond to the permission information so that the core network device can determine that the terminal has completed the update of the switching mode configuration.

[0082] In a fifth aspect, an embodiment of the present application provides a communication device. The communication device may include a processing unit and a transceiver unit, configured to execute: any method in the first aspect and its optional embodiments, or any method in the second aspect and its optional embodiments, or any method in the third aspect and its optional embodiments, or any method in the fourth aspect and its optional embodiments; wherein the transceiver unit is a sending unit when executing the sending step, and is a receiving unit when executing the receiving step.

[0083] In a sixth aspect, an embodiment of the present application provides a communication device, which may be a terminal or a chip applied to a terminal. The communication device may include a processor configured to execute any of the methods in the first aspect and its optional embodiments.

[0084] Optionally, when the communication device is a terminal, the processor is, for example, a system on chip (SoC) or a central processor unit (CPU); when the communication device is a chip, the processor is, for example, a core, which may include at least one execution unit, such as an arithmetic and logic unit (ALU).

[0085] Optionally, the communication device may further include a transceiver. When the communication device is a terminal, the transceiver may be a transceiver circuit, an antenna, etc.; when the communication device is a chip, the transceiver may be an input / output interface, a pin, a circuit, etc.

[0086] Optionally, the communication device may further include a memory for storing a computer program or instructions, and the processor executes the computer program or instructions stored in the memory to cause the communication device to perform any of the methods in the first aspect and its optional embodiments. When the communication device is a terminal, the memory may be a read-only memory, a random access memory, or the like; when the communication device is a chip, the memory may be a register, a cache, or the like.

[0087] In a seventh aspect, embodiments of the present application provide a communications device, which may be an access network device or a chip used in an access network device. The communications device may include a processor configured to execute any of the methods in the second aspect and its optional embodiments, or any of the methods in the third aspect and its optional embodiments.

[0088] Optionally, when the communication device is an access network device, the processor is, for example, a CPU, an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA); when the communication device is a chip, the processor is, for example, a core, which may include at least one execution unit, which is, for example, an ALU.

[0089] Optionally, the communication device may further include a transceiver. When the communication device is an access network device, the transceiver may be a transceiver circuit, an antenna, etc.; when the communication device is a chip, the transceiver may be an input / output interface, a pin, a circuit, etc.

[0090] Optionally, the communication device may further include a memory for storing a computer program or instructions, and the processor executes the computer program or instructions stored in the memory to cause the communication device to perform any of the methods in the second aspect and its optional embodiments, or to cause the communication device to perform any of the methods in the third aspect and its optional embodiments. When the communication device is an access network device, the memory may be a read-only memory, a random access memory, or the like; when the communication device is a chip, the memory may be a register, a cache, or the like.

[0091] In an eighth aspect, an embodiment of the present application provides a communication device, which may be a core network device or a chip applied to a core network device. The communication device may include a processor for executing any of the methods in the fourth aspect and its optional implementations.

[0092] Optionally, when the communication device is a core network device, the processor is, for example, a CPU, an ASIC, or an FPGA; when the communication device is a chip, the processor is, for example, a core, and the core may include at least one execution unit, and the execution unit is, for example, an ALU.

[0093] Optionally, the communication device may further include a transceiver. When the communication device is a core network device, the transceiver may be a transceiver circuit, an antenna, etc.; when the communication device is a chip, the transceiver may be an input / output interface, a pin, a circuit, etc.

[0094] Optionally, the communication device may further include a memory for storing a computer program or instruction, and the processor executes the computer program or instruction stored in the memory, so that the communication device performs any one of the methods in the fourth aspect and its optional embodiments. When the communication device is a core network device, the memory may be a read-only memory, a random access memory, or the like; when the communication device is a chip, the memory may be a register, a cache, or the like.

[0095] In a ninth aspect, an embodiment of the present application provides a communication system, the communication system comprising at least two of the following communication devices:

[0096] A communication device for executing any one of the methods in the first aspect and its optional embodiments;

[0097] A communication device that performs any method in the second aspect and its optional embodiments, or a communication device that performs any method in the third aspect and its optional embodiments;

[0098] A communication device that executes any one of the methods in the fourth aspect and its optional implementation modes.

[0099] In the tenth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed on a communication device, the communication device executes: any method in the first aspect and its optional embodiments, or any method in the second aspect and its optional embodiments, or any method in the third aspect and its optional embodiments, or any method in the fourth aspect and its optional embodiments.

[0100] In the eleventh aspect, an embodiment of the present application provides a computer program product, which includes: computer program code or computer program instructions, which, when the computer program code or computer program instructions are executed by a communication device, enable the communication device to execute: any method in the first aspect and its optional embodiments, or any method in the second aspect and its optional embodiments, or any method in the third aspect and its optional embodiments, or any method in the fourth aspect and its optional embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0101] FIG1 is a schematic diagram of the architecture of a communication system used in an embodiment of the present application;

[0102] FIG2 is a schematic diagram of an architecture of a core network provided in an embodiment of the present application;

[0103] FIG3 is another schematic diagram of the architecture of the core network provided in an embodiment of the present application;

[0104] FIG4 is a schematic diagram of a cell handover scenario provided in an embodiment of the present application;

[0105] FIG5 is a schematic diagram of a cell handover based on an Xn interface provided in an embodiment of the present application;

[0106] FIG6 is a schematic diagram of a registration process provided in an embodiment of the present application;

[0107] FIG7 is a schematic diagram of a dual-connection scenario provided by an implementation of the present application;

[0108] FIG8 is a schematic diagram of another dual-connection scenario provided by an implementation of the present application;

[0109] FIG9 is a schematic diagram of a communication method provided in an embodiment of the present application;

[0110] FIG10 is a schematic diagram of another communication method provided in an embodiment of the present application;

[0111] FIG11 is a schematic diagram of another communication method provided in an embodiment of the present application;

[0112] FIG12 is a schematic diagram of another communication method provided in an embodiment of the present application;

[0113] FIG13 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0114] FIG14 is a schematic structural diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0115] The technical solution in this application will be described below with reference to the accompanying drawings.

[0116] Figure 1 is a schematic diagram of the architecture of a communication system 1000 used in an embodiment of the present application. As shown in Figure 1, the communication system includes a radio access network (RAN) 100, wherein the RAN 100 includes at least one RAN node (such as 110a-110b in Figure 1, collectively referred to as 110), and may also include at least one terminal (such as 120a-120j in Figure 1, collectively referred to as 120). The RAN 100 may also include other RAN nodes, such as wireless relay devices and / or wireless backhaul devices (not shown in Figure 1). The terminal 120 is connected to the RAN node 110 via a wireless connection. Terminals and RAN nodes can be connected to each other via wired or wireless connections. The communication system 1000 may also include a core network (CN) 200. The RAN node 110 is connected to the core network 200 via a wireless or wired connection. The core network devices in the core network 200 and the RAN nodes 110 in the RAN 100 may be independent and different physical devices, or may be the same physical device that integrates the logical functions of the core network devices and the logical functions of the RAN nodes.

[0117] RAN100 may be an evolved universal terrestrial radio access (E-UTRA) system, a new radio (NR) system, or a future radio access system defined in the 3rd Generation Partnership Project (3GPP), or a WiFi system. RAN100 may also include two or more of the aforementioned different radio access systems. RAN100 may also be an open RAN (O-RAN).

[0118] A RAN node, also known as a network device, access network device, wireless access network device, RAN entity, or access node, is used to help terminals access the communication system wirelessly. Optionally, a RAN node can also be referred to as RAN for short.

[0119] In one application scenario, a RAN node may be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation NodeB (gNB) in a fifth-generation (5G) mobile communication system, a next-generation base station in a sixth-generation (6G) mobile communication system, a base station in a future mobile communication system, an access point (AP) in a WiFi system, an AP in a long-range radio (LoRa) system, or an AP in a connected vehicle system. A RAN node may be a macro base station (such as 110a in FIG. 1 ), a micro base station, an indoor station (such as 110b in FIG. 1 ), a relay node, or a donor node.

[0120] In another application scenario, multiple RAN nodes can collaborate to help terminals achieve wireless access, with different RAN nodes implementing portions of the base station's functions. For example, a RAN node can be a centralized unit (CU), a distributed unit (DU), or a radio unit (RU). The CU implements the base station's radio resource control (RRC) protocol and packet data convergence protocol (PDCP), as well as the service data adaptation protocol (SDAP). The DU implements the base station's radio link control (RLC) and medium access control (MAC) layer functions, and may also implement some or all of the physical (PHY) layer functions. For detailed descriptions of each of these protocol layers, refer to the relevant 3GPP technical specifications. The RU can be used to implement the transmission and reception of RF signals. The CU and DU can be configured as two independent RAN nodes, or they can be integrated into the same RAN node, such as in the baseband unit (BBU). The RU may be included in a radio frequency device, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH). The CU can be further divided into two types of RAN nodes: the central unit control plane (CU-CP) and the user plane (CU-UP).

[0121] In different systems, RAN nodes may have different names. For example, in an O-RAN system, a CU may be called an open CU (O-CU), a DU may be called an open DU (O-DU), and a RU may be called an open RU (O-RU). The RAN node in the embodiments of the present application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module. For example, the RAN node may be a server loaded with the corresponding software module. The embodiments of the present application do not limit the specific technology and specific device form adopted by the RAN node. For ease of description, the following description takes a base station as an example of a RAN node.

[0122] A terminal is a device with wireless transceiver capabilities that can send and receive signals to and from a base station. It can also be called a terminal device, user equipment (UE), mobile station, or mobile terminal. Terminals can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communications, machine-type communications (MTC), the Internet of Things (IoT), virtual reality (VR), augmented reality (AR), industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, and smart cities. The terminal may be a mobile phone (such as 120a, 120e, 120f, and 120j in Figure 1), a laptop computer (such as 120g in Figure 1), a printer with wireless transceiver function (such as 120h in Figure 1), a wearable device, a vehicle (such as 120b in Figure 1), a charging station (such as 120c in Figure 1), an airplane (such as 120i in Figure 1), a ship, a robot, a robotic arm, a smart home device, etc. The embodiments of this application do not limit the specific technology and specific device form adopted by the terminal.

[0123] As an example and not a limitation, in the embodiments of the present application, wearable devices may also be referred to as wearable smart devices, which are a general term for wearable devices that are intelligently designed and developed using wearable technology for daily wear, such as glasses, gloves, watches, clothing, and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothes or accessories. Wearable devices are not just hardware devices, but also achieve powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include electronic devices that are full-featured, large in size, and can achieve full or partial functions without relying on smartphones, such as smart watches or smart glasses, or electronic devices that only focus on a certain type of application function and need to be used in conjunction with other devices such as smartphones, such as various smart bracelets and smart jewelry for measuring vital signs.

[0124] As an example and not a limitation, in the embodiments of the present application, the vehicle may be a smart car (or intelligent car), a digital car (or digital car), an unmanned car (or driverless car, or pilotless car, or automobile), a self-driving car (or autonomous car), or an electric vehicle (or EV), wherein the EV may be a pure electric vehicle (or battery EV), a hybrid electric vehicle (or HEV), a range-extended EV (or REEV), a plug-in hybrid electric vehicle (or PHEV), or a new energy vehicle (or new energy vehicle). The various terminals described above, if located on a vehicle (e.g., placed in or installed in a vehicle), may be considered as on-board terminals, which may also be referred to as on-board modules, on-board chips, or on-board units (or OBUs).

[0125] Base stations and terminals can be fixed or mobile. They can be deployed on land, indoors or outdoors, handheld or vehicle-mounted; on water; or on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of base stations and terminals.

[0126] The roles of base stations and terminals can be relative. For example, 120i in Figure 1 (which can be a helicopter or drone) can be configured as a mobile base station. For 120j accessing the wireless access network 100 via 120i, 120i is a base station; however, for 110a, 120i is a terminal. That is, communication between 110a and 120i occurs via a wireless air interface protocol. Of course, communication between 110a and 120i can also occur via a base station-to-base station interface protocol. In this case, 120i is also a base station relative to 110a. Therefore, base stations and terminals can be collectively referred to as communication devices. 110a and 110b in Figure 1 can be referred to as communication devices with base station functionality, while 120a-120j in Figure 1 can be referred to as communication devices with terminal functionality.

[0127] Communication between base stations and terminals, between base stations, and between terminals can be carried out through authorized spectrum, unauthorized spectrum, or both; communication can be carried out through spectrum below 6 gigahertz (GHz), spectrum above 6 GHz, or spectrum below 6 GHz and spectrum above 6 GHz. The embodiments of the present application do not limit the spectrum resources used for wireless communication.

[0128] In the embodiments of the present application, the functions of the base station may also be performed by a module (such as a chip) in the base station, or by a control subsystem that includes the base station functions. The control subsystem that includes the base station functions here may be a control center in the above-mentioned application scenarios such as smart grid, industrial control, smart transportation, and smart city. The functions of the terminal may also be performed by a module (such as a chip or modem) in the terminal, or by a device that includes the terminal functions.

[0129] The functions of the core network 200 are briefly introduced below.

[0130] The core network 200 primarily provides user connectivity, user management, and service bearer services, and acts as a bearer network, providing an interface to external networks (e.g., the Internet 300). Alternatively, the core network 200 can be functionally divided into the architectures shown in Figures 2 or 3. Figure 2 depicts a core network based on a non-service-based architecture, while Figure 3 depicts a core network based on a service-based architecture (SBA).

[0131] SBA primarily manifests itself on the control plane. Its essence lies in defining network functions as a number of flexibly callable "service" modules, following the principles of "self-contained, reusable, and independently manageable." This allows operators to flexibly customize their networks based on business needs. Interactions between network functions are implemented through service invocations. Each network function presents a common service-oriented interface that can be called by authorized network functions or services.

[0132] As shown in Figure 2 or Figure 3, the core network 200 includes a user plane function (UPF), an access and mobility management function (AMF), a session management function (SMF), a unified data management function (UDM) and an authentication server function (AUSF).

[0133] The above-mentioned UPF, AMF, SMF, UDM and AUSF can be called core network network elements or core network devices. These network elements can be independent hardware devices, or modules integrated in the same hardware device to implement different functions. They can also be software functions running on dedicated hardware or virtualized functions instantiated on a cloud platform. The embodiments of this application do not limit the specific form of the core network network elements.

[0134] The following is a brief introduction to the core network elements in Figure 2 or Figure 3.

[0135] UPF, also known as user plane equipment, user plane functional network element, user plane network element, or user plane functional entity, is the 5G nomenclature for user plane functional network elements. UPFs primarily include the following user plane-related functions: packet routing and transmission, packet inspection, service usage reporting, QoS processing, lawful interception, uplink packet inspection, downlink packet storage, and other user plane-related functions.

[0136] Optionally, UPF can be divided into protocol data unit (PDU) session anchor UPF (PDU session anchor UPF, PSA-UPF) and intermediate UPF (intermediate UPF, I-UPF), where PSA-UPF is a UPF that supports the PDU session anchor function and is connected to the DN through the N6 interface, responsible for data transmission between the core network and the DN; all UPFs between RAN and PSA-UPF can be called I-UPF, I-UPF and RAN can be connected through the N3 interface, and I-UPF and PSA-UPF can be connected through the N9 interface.

[0137] AMF, also known as mobility management device, is the name for the mobility management network element in the 5G architecture. The mobility management network element primarily includes the following access and mobility-related functions: connection management, mobility management, registration management, access authentication and authorization, reachability management, security context management, and so on.

[0138] SMF is the name for the session management function (SMF) in the 5G architecture. It manages sessions, executes control policies issued by the policy control function (PCF), selects the UPF, and allocates Internet Protocol (IP) addresses to UEs.

[0139] UDM, also known as unified data management network element, unified data management entity, or data management device, is the name of the unified data management network element in the 5G architecture. It is mainly used to handle terminal device identification, access authentication, registration, and mobility management.

[0140] AUSF, which can also be called authentication service function network element, authentication service function entity, authentication service device, or authentication device, can be understood as the name of the authentication service function network element in the 5G architecture. The authentication service function network element is mainly used for user authentication. For example, after the authentication service function network element receives the authentication request initiated by the contracted user, it can authenticate and / or authorize the contracted user through the authentication information and / or authorization information stored in the unified data management network element, or generate the authentication and / or authorization information of the contracted user through the unified data management network element. The authentication service function network element can feedback the authentication information and / or authorization information to the contracted user. In one possible implementation method, the authentication service function network element can also be co-located with the unified data management network element.

[0141] DN is an example of the Internet 300, which is a network located outside the operator network. The operator network (such as the core network 200) can access multiple DNs. Various services can be deployed on the DN, which can provide data and / or voice services to terminal devices. For example, DN is the private network of a smart factory. The sensors installed in the workshop of the smart factory can be terminal devices. The control server of the sensors is deployed in the DN, and the control server can provide services for the sensors. The sensors can communicate with the control server, obtain instructions from the control server, and transmit the collected sensor data to the control server according to the instructions. For another example, DN is the internal office network of a company. The mobile phones or computers of the company's employees can be terminal devices. The employees' mobile phones or computers can access information, data resources, etc. on the company's internal office network.

[0142] In Figure 2, Uu, N1, N2, N3, N4, N6, N8, N9, N10, N11, N12, N13, and N14 are interface numbers, where the dotted lines corresponding to N9 and N14 indicate that these two interfaces are optional interfaces. In Figure 3, Namf is the service-based interface corresponding to AMF, Nsmf is the service-based interface corresponding to SMF, Nausf is the service-based interface corresponding to AUSF, and Nudm is the service-based interface corresponding to UDM. The meanings of these interfaces shown in Figures 2 and 3 can be found in the meanings defined in the 3GPP standard protocol and are not limited here.

[0143] The above network architecture is only an example description. The network architecture applicable to the embodiments of the present application is not limited to this. Any network architecture that can implement the functions of the above-mentioned network elements is applicable to the embodiments of the present application.

[0144] The above naming is defined only to facilitate the distinction between different functions and should not constitute any limitation to this application. This application does not exclude the possibility of adopting other naming in 5G networks and other future networks. For example, in a 6G network, some or all of the above network elements may continue to use the terminology used in 5G, or may adopt other names. The above interface name is only an example. The name of the interface in a specific implementation may be other names, and this application does not specifically limit this.

[0145] To facilitate understanding of the embodiments of the present application, the following briefly introduces the technologies involved in the embodiments of the present application.

[0146] 1. Cell handover

[0147] A cell can be considered as providing a wireless signal coverage area identified by a PCI or CGI. The coverage area of ​​each base station can be divided into one or more cells. In WiFi, the range covered by the signal of a wireless access point (AP) can also be considered as one or more cells. In the embodiments of the present application, different cells can correspond to different base stations, that is, different cells can be managed by different base stations, or different cells can belong to different RANs.

[0148] The above description of the cell is an example rather than a limitation. With the development of technology, concepts with the same or similar functions as the cell may emerge, and these concepts are also applicable to the embodiments of the present application.

[0149] Due to changes in the terminal's mobility or channel state, the cell to which the terminal is connected may change, that is, the terminal may switch from one cell to another. The cell before the switch may be called the source cell or anchor cell, and the cell after the switch may be called the target cell. As an optional example, cell switching may be interpreted as the terminal performing data transmission on the target cell and ceasing data transmission on the source cell, or cell switching may be interpreted as a change in the transmitting cell.

[0150] FIG4 is a schematic diagram of a cell handover scenario.

[0151] In Figure 4, Cell 1 and Cell 2 belong to different RANs. A terminal is currently transmitting data in Cell 1. As the terminal moves from Cell 1 to Cell 2, the channel conditions in Cell 1 deteriorate. The terminal can then use Cell 2 for transmission and no longer use Cell 1. Cell 1 is then called the source cell, and Cell 2 is called the target cell. The process of switching from transmitting data through Cell 1 to transmitting data through Cell 2 is called cell handover.

[0152] It should be noted that the cell handover may be triggered by a base station, a terminal, or a third-party device other than a base station and a terminal.

[0153] Cell switching can be divided into switching based on the Xn interface and switching based on the N2 interface. The following describes these two situations respectively.

[0154] 1.1. Cell switching based on the Xn interface.

[0155] Figure 5 is a schematic diagram of a cell handover based on the Xn interface, provided in an embodiment of the present application. The Xn interface is an interface between base stations. If the signal quality of the source cell is poor and the terminal needs to switch to the target cell, a cell handover based on the Xn interface can be implemented. During a cell handover based on the Xn interface, the AMF serving the terminal typically remains unchanged.

[0156] S501, cell switching preparation.

[0157] Before executing the handover, the terminal and the source cell need to perform handover preparation operations. For example, the source cell will configure the terminal to perform a measurement process. The terminal measures the signal quality of surrounding cells (including the target cell) according to the measurement configuration and reports the measurement report to the source cell. The source cell will decide to execute the handover process for the terminal based on the measurement report.

[0158] S502: The source cell sends a RAN data usage report (RAN Usage data report) to the AMF.

[0159] If the PLMN is configured with a second radio access technology (RAT) usage data report, the source cell may provide the AMF with a RAN data usage report, which may include N2 session information (N2 SM Information) and other content.

[0160] S503: The target cell sends an N2 Path Switch Request to the AMF.

[0161] The target cell sends an N2 Path Switch Request message to the AMF, notifying the AMF that the terminal has moved to the new cell and providing a list of PDU sessions to be switched. The N2 Path Switch Request message may include N2 SM Information and other content.

[0162] S504, AMF sends a session context request (Nsmf_PDUSession_UpdateSMContext Request) to SMF.

[0163] After receiving the N2 SM Information of the source cell and the target cell, the AMF caches the relevant information and sends the N2 SM Information to the SMF.

[0164] S505, SMF sends an N4 session modification request (N4 Session Modification Request) to UPF.

[0165] Depending on the network deployment, the CN tunnel information (CN Tunnel Info) of the UPF used to connect the target cell and the source cell may be different. If the CN tunnel information of the UPF needs to be reallocated, the CN tunnel information is allocated by the SMF, and the SMF can provide the CN tunnel information to the UPF through the N4 session modification request.

[0166] S506, UPF sends an N4 Session Modification Response to SMF.

[0167] The UPF may send an N4 session modification response to the SMF after the PDU session corresponding to the N4 session modification request is switched. Optionally, for a PDU session whose user plane resources are not released, if the UPF has allocated CN tunnel information and needs to allocate different CN tunnel information, the UPF may carry the tunnel information of the uplink traffic in the N4 session modification response.

[0168] S507, UPF sends an N3 End Marker.

[0169] After the path switch, the UPF can send one or more "End Marker" data tables for each N3 tunnel on the old path to assist the target cell in reordering. Subsequently, the UPF can send downlink data to the target cell.

[0170] S508, SMF sends a session context response (Nsmf_PDUSession_UpdateSMContext Response) to AMF.

[0171] For a successfully switched PDU session, the SMF sends the CN tunnel information to the AMF via a session context response. The CN tunnel information is used to establish the N3 tunnel. For a PDU session that is deactivated or releases user plane resources, the session context response sent by the SMF to the AMF does not carry the CN tunnel information, and the SMF then releases the PDU session. S508 can be executed at any time after the SMF receives the N4 session modification response.

[0172] S509, AMF sends an N2 Path Switch Request Ack to the target cell.

[0173] The N2 Path Switch Request Acknowledgement may include N2 SM Information, Failed PDU Sessions, and UE Radio Capability ID. After receiving the Session Context Response, the AMF may write the CN tunnel information as part of the N2 SM Information into the N2 Path Switch Request Acknowledgement and send it to the target cell.

[0174] S510: The target cell instructs the source cell to release resources.

[0175] The target cell can indicate the handover success to the source cell, triggering the source cell to release resources.

[0176] S511, the terminal executes the registration process.

[0177] If the conditions for mobility registration update are met, the terminal may initiate a mobility registration update process.

[0178] 1.2. Cell switching based on N2 interface.

[0179] Due to new wireless conditions or load balancing requirements, if the source cell does not find the Xn interface of the target cell, or the source cell receives an error indication of Xn handover failure, or the source cell determines to trigger the cell handover process based on the N2 interface based on the learned dynamic information, the source cell can perform the cell handover process based on the N2 interface.

[0180] Compared with the cell handover process based on the Xn interface, in the cell handover process based on the N2 interface, there may be no Xn interface between the base station of the target cell and the base station of the source cell, and some terminal context information can be transmitted through the AMF; since the AMF managing the base station of the target cell can be different from the AMF managing the base station of the source cell, the process may also involve the selection and switching of the target AMF. N2 handover can be divided into two stages:

[0181] Preparation stage:

[0182] Before the source cell determines to initiate a handover process, the source cell may send RRC configuration information to the terminal and a list of cells whose signal quality needs to be measured to the terminal. The cell list may be an allow-list indicating cells that can be reselected (which can be understood as cells that can be subsequently switched to), or the cell list may be an exclude-list, where the exclude-list indicates cells for which the terminal cannot perform cell reselection (which can be understood as the terminal will not subsequently switch to the cell). The terminal may perform signal quality measurements on cells in the allow-list or on cells outside the exclude-list. The terminal periodically generates a measurement report and sends it to the source cell. The source cell may initiate a handover process based on the measurement report. For example, when the signal quality of the source cell is lower than a certain threshold and there is a neighboring cell with better signal quality, such as higher than a certain threshold, the source cell determines to switch the terminal to the neighboring cell.

[0183] After the source cell initiates the handover process, the main work completed in the preparation phase is the resource allocation of the target side core network and wireless network, for example: SMF selects a new target UPF as the intermediate UPF, establishes an N9 interface tunnel between the target UPF and PSA-UPF, allocates wireless resources to the target cell, establishes an N3 interface tunnel between the target cell and the target UPF, and establishes a UE context on the target AMF.

[0184] Execution phase: The source cell notifies the terminal of the handover. After the terminal switches, the target cell notifies the target AMF, the target AMF notifies the source AMF, and the source AMF releases the session for which the handover was rejected. The target SMF notifies the PSA-UPF of the target UPF information, completing the handover of the downlink data channel. After the handover is completed, subsequent processes may also include the registration process, the release of resources on the source UPF and the source cell, and the release of resources on the indirect data forwarding tunnel.

[0185] 1.3. Registration process for 3GPP access type.

[0186] As shown in FIG6 , the registration process of the 3GPP access type includes the following contents.

[0187] S601: The terminal sends a registration request to the RAN.

[0188] The terminal can send an access network (AN) message to the RAN (equivalent to a cell), and the AN message includes AN parameters and a registration request. The AN parameters can be used by the RAN to select the AMF. The registration request includes the registration type and terminal identification information, where the terminal identification information may include a subscription concealed identifier (SUCI) or a 5G global unique temporary UE identifier (5G-GUTI).

[0189] S602: RAN selects a suitable AMF.

[0190] S603: RAN sends the registration request sent by the terminal to AMF.

[0191] S604: AMF selects the appropriate AUSF to perform authentication and other security processes.

[0192] The terminal, AMF, AUSF and UDM can complete security processes such as authentication through interaction.

[0193] S605: AMF and UDM interact to complete the signing process.

[0194] After the terminal and the network successfully authenticate each other, AMF interacts with UDM to obtain the terminal's contract data.

[0195] S606: AMF sends a Registration Accept message to the RAN.

[0196] The AMF may send a registration acceptance message to the RAN through an N2 message. The N2 message may also include a non-access stratum (NAS) message sent by the AMF to the terminal.

[0197] S607: RAN forwards the AMF registration acceptance message to the terminal.

[0198] 2. Dual connection.

[0199] In the embodiments of the present application, dual connectivity refers to a communication mode in which a terminal establishes at least two RRC connections with at least two RANs. Dual connectivity may also be referred to as multiple connectivity, dual 3GPP access, multiple 3GPP access, dual 3GPP access type, multiple 3GPP access type, dual 3GPP radio access technology (dual 3GPP RAT), multiple 3GPP radio access technology (multiple 3GPP RAT), dual steer, multiple steer, dual radio capability, multiple radio capability, same access type, same radio access technology (same RAT), or same access network, etc.

[0200] Figure 7 is a schematic diagram of a dual connectivity scenario provided by the implementation of this application. The terminal establishes two RRC connections with RAN1 and RAN2 respectively. Optionally, the terminal can also establish communication connections with more RANs, which can be RRC connections or non-RRC connections.

[0201] Figure 8 is a schematic diagram of another dual-connectivity scenario provided by an embodiment of the present application. A terminal establishes two RRC connections with RAN1 and RAN2, respectively, and also establishes user plane connections with UPF1 and UPF2, respectively. A communication interface may or may not exist between UPF1 and UPF2.

[0202] In a dual-connectivity scenario, a terminal can proactively establish multiple RRC connections with multiple RANs and send or receive data through these multiple RRC connections. If the signal quality of one of the RRC connections is poor, the terminal can use the other RRC connections for communication. Taking Figure 7 as an example, after the terminal establishes two RRC connections with RAN1 and RAN2 respectively, if the signal quality of the RRC connection between the terminal and RAN1 is poor, the terminal can disconnect the RRC connection with RAN1 and use the RRC connection with RAN2 to transmit data; or, the terminal can no longer use the RRC connection with RAN1 to transmit data, but instead use the RRC connection with RAN2 to transmit data, wherein the RRC connection with RAN1 can be retained and signaling can continue to be transmitted through the RRC connection with RAN1, or signaling can be transmitted through the RRC connection with RAN2. These situations can be referred to as dual-connectivity switching.

[0203] 3. Equivalent PLMN.

[0204] An equivalent PLMN (EPLMN) also known as an equivalent PLMN shares some of the same information as a registered PLMN (RPLMN), such as frequency and scrambling code. This information may be stored in the terminal, helping to speed up cell selection. For cell handover, a terminal can directly switch to a cell corresponding to an equivalent PLMN (or the same PLMN) while in RRC connection, without disconnecting the RRC connection to perform network selection.

[0205] The effects of dual connectivity handover and cell handover are essentially the same. Since these two mechanisms are not mutually exclusive, in some scenarios, a terminal can switch to a target cell through either cell handover or dual connectivity handover. If a terminal uses both handover methods simultaneously, conflicts may occur, leading to issues.

[0206] For example, after the terminal switches to the target cell through dual connection switching, it establishes an RRC connection with the target cell. If the terminal switches to the target cell again through cell switching, the terminal will attempt to establish another RRC connection with the target cell. If the target cell does not support establishing two RRC connections with the same terminal, the cell switching will fail. Even if the target cell supports establishing two RRC connections with the same terminal, there may be problems such as signal interference between the two RRC connections. In addition, if the target cell selected for dual connection switching is inconsistent with the target cell selected for cell switching, the terminal may release the connection with one of the target cells. In this case, the terminal establishes connections with multiple target cells separately during the switching process, resulting in unnecessary signaling overhead.

[0207] The following describes the communication method provided by the embodiments of the present application.

[0208] As shown in FIG9 , method 900 includes the following contents.

[0209] S910 , the terminal sends first information to the access network device, indicating that the terminal supports multiple switching modes, where the multiple switching modes include a first switching mode and a second switching mode.

[0210] Correspondingly, the access network device receives first information from the terminal.

[0211] It should be noted that, with the development of technology, most terminals may support multiple switching modes. The access network device and the core network device may assume that the terminal supports multiple switching modes by default, and the terminal does not need to send the first information. Therefore, in various embodiments of the present application, the steps related to the first information (such as S910 and S920) are optional steps.

[0212] In various embodiments of the present application, the access network device may be the RAN node described above, which provides the function of a source cell. The communication connection between the terminal and the source cell may be referred to as a first path. The first path may also include other connections, such as one or more of a connection between the access network device and a core network device, a connection between different core network devices, and a connection between the core network device and a DN.

[0213] The first information can be carried in an AN message or a NAS message. The embodiments of the present application do not limit the message that carries the first information.

[0214] The first switching mode may be a switching mode based on cell switching, and the second switching mode may be a switching mode based on dual connectivity; or the first switching mode may be a switching mode based on dual connectivity, and the second switching mode may be a switching mode based on cell switching. For ease of description, the following description will take the former case as an example.

[0215] In various embodiments of the present application, the first switching mode and the second switching mode are used to switch paths. A path may also be referred to as a connection, communication connection, data connection, user plane connection, channel, data channel, user plane channel, tunnel, channel, flow, or data flow, etc. The first switching mode may also be referred to as a first change mode or a first transfer mode, etc. The second switching mode may also be referred to as a second change mode or a second transfer mode, etc.

[0216] Optionally, “the first information indicates that the terminal supports multiple switching modes, and the multiple switching modes include a first switching mode and a second switching mode” can be alternatively expressed as:

[0217] The first information indicates that the terminal has multiple switching capabilities; or,

[0218] The first information indicates that the terminal supports a second switching mode, wherein the second switching mode is a switching mode based on dual connectivity; or

[0219] The first information indicates that the terminal has a capability of a second switching mode, wherein the second switching mode is a switching mode based on dual connectivity.

[0220] Since the first switching mode is a relatively popular technology, the first information indicates that the terminal supports the second switching mode, and the access network device and the core network device may understand that the terminal supports multiple switching modes.

[0221] The first information can be a dedicated bit. For example, the value of this bit is 1, indicating that the terminal supports multiple switching modes, or indicating that the terminal supports the second switching mode; the value of this bit is 0, indicating that the terminal does not support multiple switching modes, or indicating that the terminal does not support the second switching mode.

[0222] The first information may also be implemented by multiplexing other information. For example, the pilot sequence sent by the terminal to the access network device includes sequence 1 and sequence 2. The terminal may indicate that it supports multiple switching modes (or the second switching mode) by sending sequence 1, and may indicate that it does not support multiple switching modes (or the second switching mode) by sending sequence 2.

[0223] The embodiments of the present application do not limit the specific form of the first information.

[0224] In addition, the terminal can send the first information at the time of initial access, or can send the first information in the RRC connected state or the RRC idle state, or can send the first information in other situations. The embodiments of the present application do not limit the specific time when the terminal sends the first information.

[0225] S920: The access network device sends first information to the core network device.

[0226] Accordingly, the core network device receives the first information from the access network device. The core network device is, for example, an AMF. After receiving the first information, the access network device determines that the terminal supports multiple switching modes. The access network device may select an AMF that supports multiple switching modes and send the first information to the AMF.

[0227] The access network device can send the first information to the AMF through a next generation application protocol (NGAP) message or an N2 message, or can send the first information to the AMF through other methods. The embodiments of the present application do not limit the specific method in which the access network device sends the first information.

[0228] It should be noted that the first information sent by the terminal and the first information sent by the access network device may have different forms. For example, the first information sent by the terminal is carried in message A, and the first information sent by the access network device is carried in message B; or, the first information sent by the terminal multiplexes other information, and the first information sent by the access network device is a dedicated bit.

[0229] S930: The core network device sends permission information to the access network device. The permission information indicates that the terminal is allowed to perform multiple switching modes, or the permission information indicates that the terminal is allowed to perform the second switching mode.

[0230] Accordingly, the access network device receives permission information from the core network device.

[0231] In various embodiments of the present application, the permission information may be referred to as authorization information, instruction information, policy information, support information, etc. The embodiments of the present application do not limit the specific name of the permission information.

[0232] The permission information indicates that the terminal is allowed to perform multiple switching modes, which can also be expressed as:

[0233] The permission information indicates that the network supports multiple handover modes; or the permission information authorizes the terminal to perform multiple handover modes.

[0234] The permission information indicates that the terminal is allowed to perform the second switching mode, which can also be expressed as:

[0235] The permission information indicates that the network supports the second switching mode; or the permission information authorizes the terminal to execute the second switching mode.

[0236] The core network device also includes a UDM, for example. After the AMF forwards the first information to the UDM, the UDM determines whether the terminal is allowed to execute multiple switching modes, or the UDM determines whether the terminal is allowed to execute the second switching mode. For example, the UDM may determine whether the terminal is allowed to execute the second switching mode based on the subscription data of the terminal. If the UDM determines that the terminal is allowed to execute multiple switching modes, it may send permission information to the AMF, and the AMF may forward the permission information to the access network device.

[0237] The core network device can send permission information to the access network device in an explicit or implicit manner. For example, when explicitly indicating permission, the permission information can be a dedicated bit whose value is 1, indicating that the terminal is allowed to perform multiple handover modes, or that the terminal is allowed to perform the second handover mode. When implicitly indicating permission, the permission information can be an empty set, which is the cell set or PLMN set corresponding to the first handover mode. Optionally, the core network device can also send both the dedicated bit and the empty set to the access network device.

[0238] In one possible implementation, the permission information is optional information; for example, when the terminal does not need to provide the first information, the core network device may consider that the terminal is allowed to execute the first switching mode and the second switching mode. At this time, the core network device does not need to send permission information to the access network device, that is, the default terminal can execute the first switching mode and the second switching mode.

[0239] In the case where both the core network device and the terminal support multiple switching modes, the core network device and the terminal may decide to preferentially execute the first switching mode or the second switching mode. The following describes these two situations respectively.

[0240] Case 1: The core network device decides to prioritize the first switching mode or the second switching mode.

[0241] If the core network device decides to prioritize the second switching mode, the permission information may carry some information indicating the access network device. For example, the permission information includes at least one of the following information:

[0242] fifth information, instructing the access network device not to perform the first switching mode;

[0243] Sixth information, instructing the access network device to execute the second switching mode;

[0244] a first PLMN set, wherein the PLMNs in the first PLMN set are not equivalent to the PLMN of the first cell, and the first cell is a cell on the first path;

[0245] The seventh information indicates that the priority of the first switching mode is lower than the priority of the second switching mode.

[0246] Indicates the priority of the access technology type of the first switching manner and / or the priority of the access technology type of the second switching manner.

[0247] In some cases, if the core network device determines not to execute the first switching mode, the core network device may instruct the access network device not to execute the first switching mode through one or more information in the permission information, wherein the fifth information and the sixth information may be dedicated bits, the first PLMN set may be a PLMN set from a mobility restriction list (MRL) with equivalent PLMNs removed, and the seventh information may be the RAT or frequency selection priority (RFSP) of the first switching mode and the second switching mode. The access network device may instruct the terminal not to execute operations related to the first switching mode based on the permission information, or remove cells that support the first switching mode in the allow-list (e.g., cells corresponding to equivalent PLMNs), or add cells that support the first switching mode (e.g., cells corresponding to equivalent PLMNs) to the exclude-list, thereby avoiding conflicts caused by the terminal executing the first switching mode and the second switching mode at the same time.

[0248] If the core network device decides to prioritize the first switching mode, the permission information may carry some information indicating the access network device. For example, the permission information includes at least one of the following information:

[0249] Information instructing the access network device to perform the first switching mode (e.g., a dedicated bit);

[0250] Information instructing the access network device not to perform the second switching mode (e.g., a dedicated bit);

[0251] a second PLMN set, wherein the PLMNs in the second PLMN set are equivalent to the PLMN of the first cell, and the first cell is a cell on the first path (e.g., a PLMN set with non-equivalent PLMNs removed from the MRL);

[0252] Information indicating that the priority of the first switching mode is higher than the priority of the second switching mode (eg, the RFSPs of the first switching mode and the second switching mode).

[0253] Indicates the priority of the access technology type of the first switching manner and / or the priority of the access technology type of the second switching manner.

[0254] In some cases, for example, when the access network device is a satellite, the core network device determines not to execute the second switching mode. The core network device can instruct the access network device not to execute the second switching mode through one or more information in the permission information. The access network device can instruct the terminal not to execute operations related to the second switching mode based on the permission information, or remove the cells that support the second switching mode in the allow-list (such as the cells corresponding to the non-equivalent PLMN), or add the cells that support the second switching mode (such as the cells corresponding to the non-equivalent PLMN) to the exclude-list, thereby avoiding conflicts caused by the terminal executing the first switching mode and the second switching mode at the same time.

[0255] Optionally, if the core network device decides to prioritize the first switching method, the core network device may also send a PLMN set including equivalent PLMNs to the terminal, and the core network device sends information to the terminal, which instructs the terminal to establish a connection only with the access network device corresponding to the PLMN other than the equivalent PLMN when executing the second switching method.

[0256] Optionally, the core network device may also directly send a PLMN set suitable for different switching modes to the terminal, and the terminal selects the second cell according to the PLMN set. This method will be described in detail below.

[0257] Case 2: The terminal decides to preferentially execute the first switching mode or the second switching mode.

[0258] In this case, the core network device may not instruct the access network device which switching mode to prioritize. The access network device may indicate cells suitable for different switching modes to the terminal, and the terminal decides which switching mode to prioritize.

[0259] For example, when the terminal decides to prioritize the first switching mode, signal measurement may be performed in a cell that supports the first switching mode. The cell that supports the first switching mode is, for example, a cell corresponding to the first set described below, or a cell other than the cell corresponding to the second set. When the terminal decides to prioritize the second switching mode, signal measurement may be performed in a cell that supports the second switching mode. The cell that supports the second switching mode is, for example, a cell corresponding to the second set described below, or a cell other than the cell corresponding to the first set.

[0260] When the terminal decides to prioritize the second switching mode, the terminal may also modify the actual signal measurement report to prevent the access network device from triggering the first switching mode. This method will be described in detail below.

[0261] It should be noted that in case one and case two, the priority execution of the first switching mode or the second switching mode can be determined by the core network device or terminal according to actual conditions. For example, if the access network device or the core network device only supports one switching mode (such as the first switching mode), the core network device or the terminal can decide to give priority to the first switching mode; for another example, if the power consumption of one switching mode (such as the second switching mode) is greater than the power consumption of another switching mode (such as the first switching mode), the core network device or the terminal can decide to give priority to the first switching mode. The embodiments of the present application do not limit the conditions for giving priority to the first switching mode or the second switching mode.

[0262] After receiving the permission information, the access network device can perform the following steps.

[0263] S940. The access network device sends second information to the terminal. The second information includes a first set and / or a second set. The first set indicates cells supporting the first switching mode, and the second set indicates cells supporting the second switching mode.

[0264] Correspondingly, the terminal receives second information from the access network device.

[0265] If the core network device sends the first set and / or the second set to the access network device, the access network device may forward the first set and / or the second set to the terminal. If the core network device does not send the first set and / or the second set to the access network device, the access network device may determine the first set and / or the second set based on the permission information and send the first set and / or the second set to the terminal.

[0266] Optionally, the first set and / or the second set is a cell set, then the PLMN corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, or the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, or the PLMN corresponding to the cells in the second cell set is a non-equivalent PLMN to the PLMN of the first cell, or the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell; wherein, the first cell is a cell on the first path (such as the source cell); or the cells in the first cell set are cells corresponding to a terrestrial network (TN), and the cells in the second cell set are cells corresponding to a non-terrestrial network (NTN); or the access technology type of the cells in the first cell set is the same as the access technology type of the first cell, and the access technology type of the cells in the second cell set is different from the access technology type of the first cell.

[0267] Optionally, the first set and / or the second set is a PLMN set, then the PLMNs in the first PLMN set are equivalent to the PLMN of the first cell, or, the PLMNs in the first PLMN set include the PLMN of the first cell, or, the PLMNs in the second PLMN set are not equivalent to the PLMN of the first cell, or, the PLMNs in the second PLMN set do not include the PLMN of the first cell; wherein, the first cell is a cell on the first path (e.g., the source cell).

[0268] For cell switching, the terminal can directly switch to the cell corresponding to the equivalent PLMN (or the same PLMN) in the RRC connected state without disconnecting the RRC connection to perform network selection. Therefore, configuring the first set as an equivalent PLMN set (or the same PLMN set), or configuring the first set as a cell set corresponding to the equivalent PLMN (or the cell set corresponding to the same PLMN), is conducive to the path switching method based on cell switching.

[0269] S950: The terminal switches according to the second information.

[0270] The terminal can determine, based on the second information, to switch the first path to the second path through the first switching method or the second switching method, where the second path includes a connection between the terminal and the second cell, wherein, when the first path is switched to the second path through the first switching method, the second cell belongs to the cell indicated by the first set, or the second cell does not belong to the cell indicated by the second set; or, when the first path is switched to the second path through the second switching method, the second cell belongs to the cell indicated by the second set, or the second cell does not belong to the cell indicated by the first set.

[0271] It should be noted that the second cell may be a cell that supports the first switching mode or the second switching mode, or may be a cell that supports both the first switching mode and the second switching mode. When the second cell supports both the first switching mode and the second switching mode, and when the second information includes the first set and the second set, the cells indicated by the first set and the cells indicated by the second set may both include the second cell.

[0272] The first set and the second set can be two lists (such as allow-list and exclude-list), or two groups, or other forms of information sets. The embodiments of the present application do not limit the specific forms of the first set and the second set.

[0273] For example, the second information includes a first set, which is a set of cells that support the first switching method. If the terminal determines to switch the first path to the second path through the first switching method, the terminal can measure the cells in the first set and send the measurement report to the first cell so that the first cell triggers the first switching method; if the terminal determines to switch the first path to the second path through the second switching method, the terminal may not measure the cells in the first set, but select a cell from the cells outside the first set as the second cell, establish an RRC connection with the second cell, and switch the first path to the second path through the second switching method.

[0274] For another example, the second information includes a second set, which is a set of cells that support the second switching method. If the terminal determines to switch the first path to the second path through the first switching method, the terminal can measure the cells outside the second set and send the measurement report to the first cell so that the first cell triggers the first switching method; if the terminal determines to switch the first path to the second path through the second switching method, the terminal may not measure the cells outside the second set, but select a cell from the cells in the second set as the second cell, establish an RRC connection with the second cell, and switch the first path to the second path through the second switching method.

[0275] For another example, the second information includes a first set and a second set, the first set is a set of cells supporting the first switching mode, and the second set is a set of cells supporting the second switching mode. If the terminal determines to switch the first path to the second path through the first switching mode, the terminal can measure the cells in the first set, or measure the cells outside the first set and the second set, and send the measurement report to the first cell so that the first cell triggers the first switching mode; if the terminal determines to switch the first path to the second path through the second switching mode, the terminal may not measure the cells in the first set, and the terminal may select a cell from the second set and the cells outside the first set and the second set as the second cell, establish an RRC connection with the second cell, and switch the first path to the second path through the second switching mode.

[0276] In one possible implementation, if the terminal determines to switch the first path to the second path through the second switching mode, the terminal may report the signal quality measurement reports of the cells in the first set to the first cell, wherein none of the reported cell signal quality measurement results meet the conditions for executing the first switching mode, thereby preventing the first cell from triggering the first switching mode. Exemplarily, the terminal may modify the signal quality measurement results of the cells in the first set, adjust the numerical value corresponding to the signal quality in the measurement results to a numerical value lower than the threshold for triggering the execution of the first switching mode, and report the modified measurement results to the first cell, thereby preventing the first cell from triggering the first switching mode. Exemplarily, the terminal may not perform cell measurement, but directly generate the signal quality measurement results of the cells in the first set, wherein the numerical value corresponding to the signal quality in the measurement results is lower than the threshold for triggering the execution of the first switching mode, and report the measurement results to the first cell, thereby preventing the first cell from triggering the first switching mode.

[0277] As can be seen from the above, different cells may be applicable to different switching modes, and the first set and / or the second set indicate the cells corresponding to different switching modes. After determining the switching mode, the terminal can select the second cell based on the second information. If it is determined that the switching path is to be switched through the first switching mode, the second cell can be selected from cells that support the first switching mode, or the second cell can be avoided from cells that support the second switching mode. If it is determined that the switching path is to be switched through the second switching mode, the second cell can be selected from cells that support the second switching mode, or the second cell can be avoided from cells that support the first switching mode. This can avoid problems caused by the selected cell being incompatible with the determined switching mode.

[0278] It should be noted that when the terminal switches from the first path to the second path, it can be to disconnect the first path (i.e., delete the parameters related to the first path), or to deactivate the first path (i.e., retain the parameters related to the first path but no longer use the first path to transmit data and signaling), or to switch data transmission to the second path and continue to use the first path to transmit signaling, or to switch both data transmission and signaling transmission to the second path.

[0279] The following introduces several methods provided by embodiments of the present application.

[0280] FIG10 is another communication method provided by an embodiment of the present application. In this method, the core network determines to prioritize dual connectivity switching. As shown in FIG10 , method 1000 includes the following contents.

[0281] S1001: The terminal sends a registration request message to RAN1.

[0282] The registration request message can be carried in the AN message, and the registration request message can include the terminal identifier (such as SUCI), registration type, capability information, etc. The registration type can be initial registration, mobility registration update, etc. The capability information may include one or more of the following information: DualSteer Indication, support for dual connections, or dual wireless capabilities (such as Dual Radio Capability), or multi-wireless capabilities (such as Multiple Radio Capability). The capability information is intended to let AMF1 know that the terminal has the ability to establish dual connections, so that AMF1 can determine whether to allow the terminal to actively establish dual connections based on network capabilities and / or terminal contract status. In addition to being carried in the capability information, the dual-steer indication can also be carried in the AN parameters in the AN message.

[0283] As mentioned above, dual split can be replaced by concepts such as dual connectivity. Therefore, the dual split indication can also be called: dual connection indication, multi-connection indication, dual 3GPP access indication, multi-3GPP access indication, dual 3GPP access type indication, multi-3GPP access type indication, dual 3GPP radio access technology indication, multi-3GPP radio access technology indication, multi-split indication, dual radio capability indication, multi-radio capability indication, same access type indication, same radio access technology indication, or same access network indication, etc. In other embodiments of the present application, the dual split indication can also be replaced by concepts such as dual connectivity indication.

[0284] The cell having an RRC connection between RAN1 and the terminal is an example of a first cell, the path including the first cell is a first path, and the dual split indication is an example of the first information.

[0285] S1002: RAN1 sends a registration request message to AMF1.

[0286] RAN1 receives the AN message sent by the terminal and selects an AMF according to the AN message. For example, when the AN message includes a dual split indication, RAN1 selects an AMF that supports the management of "terminals that support dual-radio capabilities / multi-radio capabilities" according to the indication information. The AMF that supports the management of "terminals that support dual-radio capabilities / multi-radio capabilities" can be understood as an AMF that supports dual registration / multi-registration (that is, the terminal can perform dual registration or multi-registration through the same access type). In various embodiments of the present application, "supporting dual registration / multi-registration" can be understood as: supporting dual registration management / multi-registration management, or supporting dual registration / multi-registration under the same access type, or supporting dual registration / multi-registration under the same access technology.

[0287] If there is no dual split indication in the AN message, RAN1 can select AMF1 based on information such as slice and PLMN ID.

[0288] After determining AMF1, RAN1 sends a registration request message from the terminal to AMF1. For example, RAN1 sends the registration request message to AMF1 via NGAP or N2 message. In one possible implementation, RAN1 can send capability information to AMF1, where the capability information includes a dual split indication.

[0289] S1003, AMF1 triggers the authentication and security procedure (e.g., authentication and security procedure).

[0290] S1003 is an optional step. After successful authentication, AMF1 can send a registration request to UDM. The registration request is used for AMF1 to register with UDM as the AMF of the service terminal.

[0291] S1004, AMF1 sends a subscription data request message to UDM.

[0292] AMF1 may request the UDM to obtain the terminal's subscription information. In one possible implementation, AMF1 may send a subscription data request message (e.g., Nudm_SDM_Get Request) to the UDM. The request message may include capability information, including a dual-split indication, indicating that the terminal supports dual-radio capability / multi-radio capability.

[0293] S1005, UDM sends a signing data response message to AMF1.

[0294] The UDM can determine whether the terminal is allowed to perform dual connection, or whether the terminal is authorized to perform dual connection, or whether the network supports dual-multiple wireless capabilities, or whether the network supports multiple wireless capabilities. In one possible implementation, the UDM can determine whether the terminal is allowed / authorized to use dual connection based on the terminal's subscription data, and / or the UDM can determine whether dual wireless connection / multiple wireless connection is supported based on the network capability (for example, the UDM can configure the capability). If the UDM allows / authorizes the terminal to use dual connection, or if the UDM supports dual wireless connection / multiple wireless connection, the UDM can send a subscription data response message (for example, Nudm_SDM_Get Response) to the AMF, which may include permission information, indicating that the terminal is allowed to perform multiple switching modes, including the first switching mode and the second switching mode; or, the permission information indicates that the terminal is allowed to perform the second switching mode. For example, the permission information can be called DualSteer Authorised or DualSteer Supported, indicating whether the terminal is allowed / authorized / supported to perform dual connection, or dual wireless connection capability / multiple wireless connection capability.

[0295] S1006: AMF1 sends an initial context establishment request message to RAN1.

[0296] The Initial Context Setup Request message may include some information instructing RAN1 not to perform cell handover, or information instructing RAN1 not to perform cell handover under specific conditions. The information carried in the Initial Context Setup Request message may be regarded as some examples of permission information.

[0297] For example, the permission information may include at least one of the following information:

[0298] Information instructing RAN1 to perform dual connectivity switching (an example of sixth information);

[0299] Information instructing RAN1 not to perform cell handover (an example of fifth information);

[0300] A mobility restriction list (MRL) that does not contain equivalent PLMN information, i.e., the PLMNs in the MRL are not equivalent to the PLMN of the first cell, so that RAN1 does not trigger the terminal to switch to the cell corresponding to the equivalent PLMN through cell handover; or an MRL that contains equivalent PLMN information and indication information, wherein the indication information instructs RAN1 to place the cell corresponding to the PLMN in the MRL in the exclude-list or remove it from the allow-list;

[0301] RFSP for cell switching and RFSP for dual-connection switching (an example of the seventh information), wherein the RFSP for cell switching is higher than the RFSP for dual-connection switching. In another possible implementation, in the RFSP for cell switching, the high-priority access technology type is different from the high-priority access technology type for performing dual-connection switching. Exemplarily, in the RFSP for cell switching, the high-priority access technology type is a terrestrial network (TN), while the high-priority access technology type corresponding to the cell performing dual-connection switching is a non-terrestrial network (NTN), such as a satellite access technology.

[0302] The above-mentioned information instructing RAN1 to perform dual connectivity switching, information instructing RAN1 not to perform cell switching, MRL not including equivalent PLMN information, MRL including equivalent PLMN information and indication information, or RFSP for cell switching and RFSP for dual connectivity switching are all examples of permission information.

[0303] Based on one or more information in the initial context establishment request message, RAN1 does not instruct the terminal to perform signal measurement (i.e., does not instruct the terminal to perform the cell switching process), or instructs the terminal not to perform signal measurement, for example, does not include any cells in the allow-list sent to the terminal; or adds cell information for which cell switching is not performed (e.g., information on cells corresponding to equivalent PLMNs) to the exclude-list sent to the terminal; or removes cell information for which cell switching is not performed (e.g., information on cells corresponding to equivalent PLMNs) from the allow-list.

[0304] S1007 , RAN1 sends an RRC reconfiguration message to the terminal.

[0305] After RAN1 determines not to perform a cell handover via the Initial Context Setup Request message, it can update configuration information to the terminal via an RRC Reconfiguration message. The updated configuration information may include: 1) an exclude list (instructing the terminal not to handover to cells in the exclude list). This exclude list may include information about cells not supported by RAN1 (e.g., neighboring cells), preventing the terminal from handing over to cells not supported by RAN1, thereby preventing handover to other RANs; or it may include a list of cells in equivalent PLMNs (e.g., neighboring cells), preventing the terminal from handing over to cells in non-equivalent PLMNs, thereby preventing handover to RANs of other PLMNs. Whether cells in the same PLMN (e.g., neighboring cells) are included in the exclude list may depend on network policy. For example, if the network only allows the terminal to establish connections to RANs of different PLMNs via dual connectivity, the cell handover mechanism within the same PLMN can be executed normally. However, inter-PLMN cell handovers may conflict with dual connectivity handovers, so only the inter-PLMN conflict needs to be resolved. If the network policy is to allow the terminal to initiate dual connections at any time, similar problems will arise within the same PLMN. Therefore, cell switching can be restricted to cells within the same RAN, or even no cell switching can be performed to avoid conflicts. 2) allow-list, which indicates the cells to which the terminal can switch. For example, when RAN1 removes all cells from the allow-list, the terminal can be enabled to not perform any cell switching; when RAN1 removes cells of other RANs from the allow-list, the terminal can be enabled to perform cell switching only within the RAN1 site, and not to perform cross-site cell switching; when RAN1 removes cells corresponding to other PLMNs from the allow-list, the terminal can be enabled to perform cell switching only within the PLMN, and not to perform cross-PLMN cell switching. In one possible implementation, switching can be understood as reselection.

[0306] The exclude-list and the allow-list may exist at the same time, or only one of them may exist. The exclude-list and / or the allow-list may be regarded as an example of the second information.

[0307] S1008: RAN1 sends an initial context establishment response message to AMF1.

[0308] The Initial Context Setup Response message indicates that AMF1 and RAN1 have established the context. Optionally, the Initial Context Setup Response message may further include information indicating that the handover mode configuration of the terminal has been updated, which may be considered as an example of the eighth information.

[0309] S1009, AMF1 sends a registration acceptance message to the terminal.

[0310] Optionally, the Registration Accept message may include indication information, such as DualSteer Supported Indication or DualSteer Authorized Indication. Optionally, the Registration Accept message or the Registration Accept message including indication information may be triggered by the Registration Request message in S1002, or in other words, the indication information in the Registration Accept message may be triggered by the DualSteer Indication in S1002. DualSteer Supported Indication or DualSteer Authorized Indication is an example of third information, wherein the third information indicates that the terminal is allowed to perform multiple switching modes, including a first switching mode and a second switching mode.

[0311] S1010: The terminal establishes a connection with RAN2.

[0312] Based on the indication information in the registration accept message, the terminal determines that dual connectivity switching can be performed. The terminal can establish a connection with RAN2 based on certain criteria and initiate a registration process (similar to S1001 to S1009). After establishing a connection with RAN2, the terminal can switch from the first path (including the path of RAN1) to the second path (including the path of RAN2). For example, if the signal quality of the first path deteriorates (e.g., falls below a signal quality threshold) after the second path is established, the terminal can switch from the first path to the second path.

[0313] FIG11 is another communication method provided by an embodiment of the present application. In this method, a terminal determines to preferentially perform dual connectivity switching. As shown in FIG11 , method 1100 includes the following contents.

[0314] S1101: The terminal sends a registration request message to RAN1.

[0315] The registration request message can be carried in the AN message, and the registration request message can include the terminal identifier (such as SUCI), registration type, capability information, etc. The registration type can be initial registration, mobility registration update, etc. The capability information may include one or more of the following information: DualSteer Indication, support for dual connections, or dual wireless capabilities (such as Dual Radio Capability), or multi-wireless capabilities (such as Multiple Radio Capability). The capability information is intended to let AMF1 know that the terminal has the ability to establish dual connections, so that AMF1 can determine whether to allow the terminal to actively establish dual connections based on network capabilities and / or terminal contract status. In addition to being carried in the capability information, the dual-steer indication can also be carried in the AN parameters in the AN message.

[0316] The cell having an RRC connection between RAN1 and the terminal is an example of a first cell, the path including the first cell is a first path, and the dual split indication is an example of the first information.

[0317] S1102: RAN1 sends a registration request message to AMF1.

[0318] RAN1 receives the AN message sent by the terminal and selects an AMF according to the AN message. For example, when the AN message includes a dual split indication, RAN1 selects an AMF that supports the management of "terminals that support dual-radio capabilities / multi-radio capabilities" according to the indication information. The AMF that supports the management of "terminals that support dual-radio capabilities / multi-radio capabilities" can be understood as an AMF that supports dual registration / multi-registration (that is, the terminal can perform dual registration or multi-registration through the same access type). In various embodiments of the present application, "supporting dual registration / multi-registration" can be understood as: supporting dual registration management / multi-registration management, or supporting dual registration / multi-registration under the same access type, or supporting dual registration / multi-registration under the same access technology.

[0319] If there is no dual split indication in the AN message, RAN1 can select AMF1 based on information such as slice and PLMN ID.

[0320] After determining AMF1, RAN1 sends a registration request message from the terminal to AMF1. For example, RAN1 sends the registration request message to AMF1 via NGAP or N2 message. In one possible implementation, RAN1 can send capability information to AMF1, where the capability information includes a dual split indication.

[0321] S1103, AMF1 triggers the authentication and security procedure (e.g., authentication and security procedure).

[0322] S1103 is an optional step. After successful authentication, AMF1 can send a registration request to UDM. The registration request is used for AMF1 to register with UDM as the AMF of the service terminal.

[0323] S1104, AMF1 sends a subscription data request message to UDM.

[0324] AMF1 may request the UDM to obtain the terminal's subscription information. In one possible implementation, AMF1 may send a subscription data request message (e.g., Nudm_SDM_Get Request) to the UDM. The request message may include capability information, including a dual-split indication, indicating that the terminal supports dual-radio capability / multi-radio capability.

[0325] S1105, UDM sends a signing data response message to AMF1.

[0326] The UDM can determine whether the terminal is allowed to perform dual connection, or whether the terminal is authorized to perform dual connection, or whether the network supports dual-multi-radio capabilities, or whether the network supports multi-radio capabilities. In one possible implementation, the UDM can determine whether the terminal is allowed / authorized to use dual connection based on the terminal's contract data, and / or the UDM can determine whether dual wireless connection / multi-wireless connection is supported based on the network capability (for example, the UDM can configure the capability). If the UDM allows / authorizes the terminal to use dual connection, or if the UDM supports dual wireless connection / multi-wireless connection, the UDM can send a contract data response message (for example, Nudm_SDM_Get Response) to the AMF, which may include DualSteer Authorised or DualSteer Supported, indicating whether the terminal is allowed / authorized / supported to perform dual connection, or dual wireless connection capability / multi-wireless connection capability. DualSteer Authorised or DualSteer Supported is an example of permission information.

[0327] S1106: AMF1 sends an initial context establishment request message to RAN1.

[0328] The Initial Context Setup Request message may include some indication or authorization information allowing RAN1 to perform dual connectivity handover or multiple handover modes, such as DualSteer Allowed Indication. RAN1 may subsequently determine whether to allow the terminal to perform dual connectivity handover based on this information. For example, if the terminal subsequently wishes to perform dual connectivity handover, it may indicate to RAN1 that it intends to perform dual connectivity handover. RAN1 may then determine that the UE is permitted to perform the handover based on the DualSteer Allowed Indication.

[0329] The above-mentioned indication information or authorization information for allowing RAN1 to perform dual connectivity switching or multiple switching modes is an example of permission information.

[0330] S1107: RAN1 sends an initial context establishment response message to AMF1.

[0331] The Initial Context Setup Response message indicates that AMF1 and RAN1 have established the context.

[0332] S1108, AMF1 sends a registration acceptance message to the terminal.

[0333] Optionally, the Registration Accept message may include indication information, such as DualSteer Supported Indication or DualSteer Authorized Indication. Optionally, the Registration Accept message or the Registration Accept message including the indication information may be triggered by the Registration Request message in S1102, or in other words, the indication information in the Registration Accept message may be triggered by the DualSteer Indication in S1102. The DualSteer Supported Indication or the DualSteer Authorized Indication is an example of the third information, wherein the third information indicates that the terminal is allowed to perform multiple switching modes, the multiple switching modes including the first switching mode and the second switching mode.

[0334] S1109: The terminal sends an RRC message to RAN1.

[0335] After receiving the registration acceptance message, the terminal determines that dual connectivity switching can be performed. If the terminal decides to start the dual connectivity switching mode, it can send fourth information to RAN1 through an RRC message, such as information indicating activation of dual split (Activate DualSteer) or information indicating initiation of dual split.

[0336] S1110 , RAN1 sends an RRC reconfiguration message to the terminal.

[0337] The RRC reconfiguration message may include an exclude-list and / or an allow-list. The meanings of exclude-list and allow-list are the same as those of exclude-list and allow-list in method 1000 and are not repeated here.

[0338] The exclude-list and / or the allow-list may be considered as an example of the second information.

[0339] S1111: The terminal establishes a connection with RAN2.

[0340] The terminal may determine to perform dual connectivity switching based on the third information in S1108 or S1110. The terminal may establish a connection with RAN2 based on certain criteria and initiate a registration process (similar to S1101 to S1110). After establishing a connection with RAN2, the terminal may switch from the first path (including the path of RAN1) to the second path (including the path of RAN2). For example, if the signal quality of the first path deteriorates (e.g., falls below a signal quality threshold) after the second path is established, the terminal may switch from the first path to the second path.

[0341] FIG12 is another communication method provided by an embodiment of the present application. In this method, a terminal determines to preferentially perform dual connectivity switching. As shown in FIG12 , method 1200 includes the following contents.

[0342] S1201: The terminal sends a registration request message to RAN1.

[0343] The registration request message can be carried in the AN message, and the registration request message can include the terminal identifier (such as SUCI), registration type, capability information, etc. The registration type can be initial registration, mobility registration update, etc. The capability information may include one or more of the following information: DualSteer Indication, support for dual connections, or dual wireless capabilities (such as Dual Radio Capability), or multi-wireless capabilities (such as Multiple Radio Capability). The capability information is intended to let AMF1 know that the terminal has the ability to establish dual connections, so that AMF1 can determine whether to allow the terminal to actively establish dual connections based on network capabilities and / or terminal contract status. In addition to being carried in the capability information, the dual-steer indication can also be carried in the AN parameters in the AN message.

[0344] The cell having an RRC connection between RAN1 and the terminal is an example of a first cell, the path including the first cell is a first path, and the dual split indication is an example of the first information.

[0345] S1202: RAN1 sends a registration request message to AMF1.

[0346] RAN1 receives the AN message sent by the terminal and selects an AMF according to the AN message. For example, when the AN message includes a dual split indication, RAN1 selects an AMF that supports the management of "terminals that support dual-radio capabilities / multi-radio capabilities" according to the indication information. The AMF that supports the management of "terminals that support dual-radio capabilities / multi-radio capabilities" can be understood as an AMF that supports dual registration / multi-registration (that is, the terminal can perform dual registration or multi-registration through the same access type). In various embodiments of the present application, "supporting dual registration / multi-registration" can be understood as: supporting dual registration management / multi-registration management, or supporting dual registration / multi-registration under the same access type, or supporting dual registration / multi-registration under the same access technology.

[0347] If there is no dual split indication in the AN message, RAN1 can select AMF1 based on information such as slice and PLMN ID.

[0348] After determining AMF1, RAN1 sends a registration request message from the terminal to AMF1. For example, RAN1 sends the registration request message to AMF1 via NGAP or N2 message. In one possible implementation, RAN1 can send capability information to AMF1, where the capability information includes a dual split indication.

[0349] S1203, AMF1 triggers the authentication and security procedure (e.g., authentication and security procedure).

[0350] S1203 is an optional step. After successful authentication, AMF1 can send a registration request to UDM. The registration request is used for AMF1 to register with UDM as the AMF of the service terminal.

[0351] S1204, AMF1 sends a subscription data request message to UDM.

[0352] AMF1 may request the UDM to obtain the terminal's subscription information. In one possible implementation, AMF1 may send a subscription data request message (e.g., Nudm_SDM_Get Request) to the UDM. The request message may include capability information, including a dual-split indication, indicating that the terminal supports dual-radio capability / multi-radio capability.

[0353] S1205, UDM sends a signing data response message to AMF1.

[0354] The UDM can determine whether the terminal is allowed to perform dual connection, or whether the terminal is authorized to perform dual connection, or whether the network supports dual-multi-radio capabilities, or whether the network supports multi-radio capabilities. In one possible implementation, the UDM can determine whether the terminal is allowed / authorized to use dual connection based on the terminal's contract data, and / or the UDM can determine whether dual wireless connection / multi-wireless connection is supported based on the network capability (for example, the UDM can configure the capability). If the UDM allows / authorizes the terminal to use dual connection, or if the UDM supports dual wireless connection / multi-wireless connection, the UDM can send a contract data response message (for example, Nudm_SDM_Get Response) to the AMF, which may include DualSteer Authorised or DualSteer Supported, indicating whether the terminal is allowed / authorized / supported to perform dual connection, or dual wireless connection capability / multi-wireless connection capability. DualSteer Authorised or DualSteer Supported is an example of permission information.

[0355] S1206: AMF1 sends an initial context establishment request message to RAN1.

[0356] The Initial Context Setup Request message may include some indication or authorization information allowing RAN1 to perform dual connectivity handover or multiple handover modes, such as DualSteer Allowed Indication. RAN1 may subsequently determine whether to allow the terminal to perform dual connectivity handover based on this information. For example, if the terminal subsequently wishes to perform dual connectivity handover, it may indicate to RAN1 that it intends to perform dual connectivity handover. RAN1 may then determine that the UE is permitted to perform the handover based on the DualSteer Allowed Indication.

[0357] The above-mentioned indication information or authorization information for allowing RAN1 to perform dual connectivity switching or multiple switching modes is an example of permission information.

[0358] S1207: RAN1 sends an initial context establishment response message to AMF1.

[0359] The Initial Context Setup Response message indicates that AMF1 and RAN1 have established the context.

[0360] S1208, AMF1 sends a registration acceptance message to the terminal.

[0361] Optionally, the Registration Accept message may include DualSteer Supported Indication or DualSteer Authorized Indication. Optionally, the Registration Accept message or the Registration Accept message including the indication information may be triggered by the Registration Request message in S1202, or in other words, the indication information in the Registration Accept message may be triggered by the DualSteer Indication in S1202. The DualSteer Supported Indication or the DualSteer Authorized Indication is an example of the third information, wherein the third information indicates that the terminal is allowed to perform multiple switching modes, including the first switching mode and the second switching mode.

[0362] Optionally, the registration accept message may include a PLMN list for DualSteer, indicating the PLMNs that are allowed to perform dual connectivity handover. Optionally, the list removes equivalent PLMNs, or the terminal may autonomously remove equivalent PLMNs after receiving the list. The PLMN list for DualSteer is an example of the third information.

[0363] Optionally, the registration accept message may include a list of cells for dual-split, indicating cells for which dual-connectivity handover is permitted. Optionally, the list may exclude cells corresponding to equivalent PLMNs. Alternatively, the terminal may autonomously remove cells corresponding to equivalent PLMNs upon receiving the list. The list of cells for dual-split is an example of the third information.

[0364] S1209: The terminal sends a measurement report to RAN1.

[0365] After receiving the registration acceptance message, the terminal determines that dual connectivity switching can be performed. If the terminal decides to perform dual connectivity switching, it can perform any of the following methods:

[0366] 1) Determine the cell that allows dual connectivity handover (eg, the cell corresponding to the non-equivalent PLMN) according to the PLMN list in S1208, perform signal measurement, and send a measurement report.

[0367] 2) Measure the signal quality of cells outside the allow-list, or measure the signal quality of cells in the exclude-list, and send a measurement report.

[0368] 3) Measure the signal quality of the cells in the allow-list, or measure the signal quality of the cells outside the exclude-list, modify the measurement report, and adjust the signal quality value in the measurement report from a first value to a second value, wherein the first value is greater than or equal to the signal quality value corresponding to the cell handover, and the second value is less than the signal quality value corresponding to the cell handover; and then send the measurement report.

[0369] 4) No cell measurement is performed, but a measurement report is generated, wherein the signal quality value of the measurement report is a second value, which is smaller than the signal quality value corresponding to the cell handover; and the measurement report is subsequently sent.

[0370] For method 3) and method 4), if the measurement report received by RAN1 indicates that the signal quality of the neighboring cell is poor, RAN1 will not trigger cell handover.

[0371] S1210: The terminal establishes a connection with RAN2.

[0372] The terminal may determine to perform dual connectivity switching based on the third information in S1208. The terminal may establish a connection with RAN2 based on certain criteria and initiate a registration process (similar to S1101 to S1110). After establishing a connection with RAN2, the terminal may switch from the first path (including the path of RAN1) to the second path (including the path of RAN2). For example, if the signal quality of the first path deteriorates (e.g., falls below a signal quality threshold) after the second path is established, the terminal may switch from the first path to the second path.

[0373] The above describes in detail the method examples provided by the embodiments of the present application. It is understandable that the corresponding device includes hardware structures and / or software modules corresponding to the execution of each function in order to realize the above functions. Those skilled in the art should easily appreciate that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in a hardware or computer software driven hardware manner 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 be beyond the scope of this application.

[0374] Figures 13 and 14 are schematic diagrams of the structures of two possible communication devices provided in embodiments of the present application. These communication devices can be used to implement the functions of the terminal, access network device, or core network device in the above-mentioned method embodiments, and thus also have the beneficial effects of the above-mentioned method embodiments. In the embodiments of the present application, these communication devices can be the terminal, RAN node, or core network device shown in Figure 1, or can be modules (e.g., chips) applied to the terminal, RAN node, or core network device.

[0375] As shown in Figure 13, the communication device 1300 includes a processing unit 1310 and a transceiver unit 1320. Under the control of the processing unit 1310, the transceiver unit 1320 performs a receiving step and / or a sending step. When performing a sending step, the transceiver unit 1320 functions as a sending unit, and when performing a receiving step, the transceiver unit 1320 functions as a receiving unit. The communication device 1300 is used to implement the functions of a terminal, access network device, or core network device in the method embodiments described in Figures 9 to 12 above.

[0376] When the communication device 1300 is used to implement the function of the terminal in the method embodiment described in Figures 9 to 12, the transceiver unit 1320 is used to: receive second information through a first path, the second information includes a first set and / or a second set, the first set indicates cells that support the first switching method, and the second set indicates cells that support the second switching method; the processing unit 1310 is used to: determine to switch the first path to a second path through the first switching method or the second switching method, the second path includes a connection between the terminal and the second cell, wherein, when the first path is switched to the second path through the first switching method, the second cell belongs to the cell indicated by the first set, or the second cell does not belong to the cell indicated by the second set; or, when the first path is switched to the second path through the second switching method, the second cell belongs to the cell indicated by the second set, or the second cell does not belong to the cell indicated by the first set.

[0377] Optionally, before receiving the second information through the first path, the transceiver unit 1320 is further configured to: send first information through the first path, where the first information indicates that the terminal supports multiple switching modes, and the multiple switching modes include a first switching mode and a second switching mode.

[0378] Optionally, before determining to switch the first path to the second path through the first switching mode or the second switching mode, the transceiver unit 1320 is also used to: receive third information through the first path, the third information indicating that the terminal is allowed to execute multiple switching modes, including the first switching mode and the second switching mode.

[0379] Optionally, before receiving the second information through the first path, the transceiver unit 1320 is further configured to: send fourth information through the first path, where the fourth information instructs the terminal to start a mode of executing the second switching manner.

[0380] Optionally, the processing unit 1310 is also used to: if it is determined that the first path is switched to the second path through the second switching method, the signal quality value of the second cell is adjusted from the first value to the second value, the first value is greater than or equal to the signal quality value corresponding to the first switching method, and the second value is less than the signal quality value corresponding to the first switching method; the transceiver unit 1320 is also used to: send the second value through the first path.

[0381] Optionally, the transceiver unit 1320 is further used to: if it is determined that the first path is switched to the second path through the second switching method, then send the signal quality value of the second cell through the first path, and the signal quality value of the second cell is lower than the signal quality value corresponding to the triggering execution of the first switching method.

[0382] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is not equivalent to the PLMN of the first cell, and the first cell is a cell on the first path.

[0383] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMN of the first cell, the PLMNs in the second PLMN set are not equivalent to the PLMN of the first cell, and the first cell is a cell on the first path.

[0384] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell, and the first cell is a cell on the first path.

[0385] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, and the first cell is a cell on the first path.

[0386] When the communication device 1300 is used to implement the function of the access network device in the method embodiments described in Figures 9 to 12, the transceiver unit 1320 is used to: receive permission information from the core network device, the permission information indicates that the terminal is allowed to execute multiple switching modes, and the multiple switching modes include a first switching mode and a second switching mode; or, the permission information indicates that the terminal is allowed to execute the second switching mode; according to the permission information, send second information to the terminal, the second information includes a first set and / or a second set, the first set indicates cells that support the first switching mode, and the second set indicates cells that support the second switching mode.

[0387] Optionally, before receiving the permission information from the core network device, the transceiver unit 1320 is also used to: receive first information from the terminal via a first path, the first information indicating that the terminal supports multiple switching modes, the multiple switching modes including a first switching mode and a second switching mode; and send the first information to the core network device.

[0388] Optionally, the transceiver unit 1320 is further configured to: send third information to the terminal, where the third information indicates that the terminal is allowed to execute multiple switching modes, where the multiple switching modes include a first switching mode and a second switching mode.

[0389] Optionally, before sending the second information to the terminal, the transceiver unit 1320 is also used to: receive fourth information from the terminal, the fourth information instructing the terminal to start the mode of executing the second switching method; the transceiver unit 1320 is specifically further used to: send the second information to the terminal according to the fourth information.

[0390] Optionally, the transceiver unit 1320 is specifically used to: send second information to the terminal via the first path, wherein the cell corresponding to the first path is the first cell; the permission information includes at least one of the following information: fifth information, indicating that the access network device does not execute the first switching method; sixth information, indicating that the access network device executes the second switching method; a first PLMN set, wherein the PLMN in the first PLMN set is not equivalent to the PLMN of the first cell, and the first cell is a cell on the first path; seventh information, indicating that the priority of the first switching method is lower than the priority of the second switching method.

[0391] Optionally, the transceiver unit 1320 is further configured to: send eighth information to the core network device, where the eighth information indicates that the switching mode configuration of the terminal has been updated.

[0392] Optionally, the transceiver unit 1320 is specifically used to: send second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is the first cell set, the second set is the second cell set, the PLMN corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, and the PLMN corresponding to the cells in the second cell set is not equivalent to the PLMN of the first cell.

[0393] Optionally, the transceiver unit 1320 is specifically used to: send second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is the first PLMN set, the second set is the second PLMN set, the PLMN in the first PLMN set is equivalent to the PLMN of the first cell, and the PLMN in the second PLMN set is not equivalent to the PLMN of the first cell.

[0394] Optionally, the transceiver unit 1320 is specifically used to: send second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, and the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell.

[0395] Optionally, the transceiver unit 1320 is specifically used to: send second information to the terminal through the first path, wherein the cell corresponding to the first path is the first cell; the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is the first PLMN set, the second set is the second PLMN set, the PLMN in the first PLMN set includes the PLMN of the first cell, and the PLMN in the second PLMN set does not include the PLMN of the first cell.

[0396] When the communication device 1300 is used to implement the function of the access network device in the method embodiment described in Figures 9 to 12, the transceiver unit 1320 is used to: receive permission information from the core network device, the permission information indicating that the terminal is allowed to execute multiple switching modes, the multiple switching modes including the first switching mode and the second switching mode; or, the permission information indicating that the terminal is allowed to execute the second switching mode; receive fourth information from the terminal through the first path, the fourth information indicating that the terminal starts a mode for executing the second switching mode; determine not to start a mode for executing the first switching mode based on the permission information and the fourth information; or, send second information to the terminal through the first path; or, send update information of the second information to the terminal through the first path; wherein the second information includes a first set and / or a second set, the first set indicates cells that support the first switching mode, and the second set indicates cells that support the second switching mode.

[0397] Optionally, before receiving the permission information from the core network device, the transceiver unit 1320 is also used to: receive first information from the terminal via a first path, the first information indicating that the terminal supports multiple switching modes, the multiple switching modes including a first switching mode and a second switching mode; and send the first information to the core network device.

[0398] Optionally, the transceiver unit 1320 is further configured to: send third information to the terminal through the first path, where the third information indicates that the terminal is allowed to execute multiple switching modes.

[0399] Optionally, the permission information includes at least one of the following information: fifth information, indicating that the access network device does not execute the first switching method; sixth information, indicating that the access network device executes the second switching method; a first PLMN set, wherein the PLMN in the first PLMN set is not equivalent to the PLMN of the first cell, and the first cell is a cell on the first path; seventh information, indicating that the priority of the first switching method is lower than the priority of the second switching method.

[0400] Optionally, the transceiver unit 1320 is further configured to: send eighth information to the core network device, where the eighth information indicates that the switching mode configuration of the terminal has been updated.

[0401] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is not equivalent to the PLMN of the first cell, and the first cell is a cell on the first path.

[0402] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMN of the first cell, the PLMNs in the second PLMN set are not equivalent to the PLMN of the first cell, and the first cell is a cell on the first path.

[0403] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first cell set, the second set is a second cell set, the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell, and the first cell is a cell on the first path.

[0404] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, and the first cell is a cell on the first path.

[0405] When the communication device 1300 is used to implement the functions of the core network device in the method embodiments described in Figures 9 to 12, the processing unit 1310 is used to: determine the permission information, the permission information indicates that the terminal is allowed to execute multiple switching modes, the multiple switching modes include a first switching mode and a second switching mode; or, the permission information indicates that the terminal is allowed to execute the second switching mode; the transceiver unit 1320 is used to: send the permission information.

[0406] Optionally, before determining the permission information, the transceiver unit 1320 is further configured to: receive first information, where the first information indicates that the terminal supports multiple switching modes, and the multiple switching modes include a first switching mode and a second switching mode.

[0407] Optionally, the permission information includes at least one of the following information: fifth information, indicating that the access network device does not execute the first switching mode; sixth information, indicating that the access network device executes the second switching mode; a first PLMN set, the PLMN in the first PLMN set is not equivalent to the PLMN of the first cell, the first cell is a cell on the first path, and the first path includes the connection between the terminal and the access network device; seventh information, indicating that the priority of the first switching mode is lower than the priority of the second switching mode.

[0408] Optionally, the permission information includes a first set and / or a second set, the first set indicates PLMNs supporting a first switching mode, and the second set indicates PLMNs supporting a second switching mode.

[0409] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMN of the first cell, the PLMNs in the second PLMN set are not equivalent to the PLMN of the first cell, the first cell is a cell on the first path, and the first path includes the connection between the terminal and the access network device.

[0410] Optionally, the first switching mode is a switching mode based on cell switching, the second switching mode is a switching mode based on dual connection, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, the first cell is a cell on the first path, the first cell is a cell on the first path, and the first path includes the connection between the terminal and the access network device.

[0411] Optionally, the transceiver unit 1320 is further configured to: receive eighth information, where the eighth information indicates that the switching mode configuration of the terminal has been updated.

[0412] Those skilled in the art can clearly understand that when the communication device 1300 is used to implement the functions of a terminal, an access network device or a core network device, the specific working process of the communication device 1300 and the technical effects produced by the execution steps can refer to the description in the corresponding method embodiment mentioned above. For the sake of brevity, they will not be repeated here.

[0413] In the communication device 1300, the processing unit 1310 can be implemented by hardware or by software. When implemented by hardware, the processing unit 1310 can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processing unit 1310 can be a general-purpose processor, which is implemented by reading the software code stored in the storage unit. The storage unit can be integrated in the processing unit 1310 or located outside the processing unit 1310 and exist independently.

[0414] As shown in Figure 14, communication device 1400 includes a processor 1410 and an interface circuit 1420. Processor 1410 and interface circuit 1420 are coupled to each other. It is understood that interface circuit 1420 can be a transceiver or an input / output interface. Optionally, communication device 1400 may also include a memory 1430 for storing instructions executed by processor 1410, input data required by processor 1410 to execute instructions, or data generated by processor 1410 after executing instructions.

[0415] When the communication device 1400 is used to implement the methods shown in FIG. 9 to FIG. 12 , the processor 1410 is used to implement the functions of the processing unit 1410 , and the interface circuit 1420 is used to implement the functions of the transceiver unit 1420 .

[0416] When communication device 1400 is a terminal chip (i.e., a chip used in a terminal), the terminal chip implements the terminal functions in the above-described method embodiments. When the terminal chip receives information from an access network device, it can be understood that the information is first received by other modules in the terminal (such as a radio frequency module or antenna) and then sent to the terminal chip by these modules. When the terminal chip sends information to the access network device, it can be understood that the information is first sent to other modules in the terminal (such as a radio frequency module or antenna) and then sent to the access network device by these modules.

[0417] When the communication device 1600 is an access network device chip (i.e., a chip used in an access network device), the access network device chip implements the functions of the access network device in the above-mentioned method embodiments. When the access network device chip receives information from a terminal, it can be understood that the information is first received by other modules in the access network device (such as a radio frequency module or antenna) and then transmitted to the access network device chip by these modules. When the access network device chip sends information to a terminal, it can be understood that the information is sent to other modules in the access network device (such as a radio frequency module or antenna) and then transmitted to the terminal by these modules.

[0418] When communication device 1600 is a core network device chip (i.e., a chip used in an access network device), the core network device chip implements the core network device functions described in the above-described method embodiments. When the core network device chip receives information from the access network device, it can be understood that the information is first received by other modules in the access network device (e.g., a communication interface module) and then transmitted to the core network device chip by these modules. When the core network device chip transmits information to the access network device, it can be understood that the information is transmitted to other modules in the core network device (e.g., a communication interface module) and then transmitted to the access network device by these modules.

[0419] In this application, when entity A sends information to entity B, it can be done directly from A to B or indirectly through another entity. Similarly, when entity B receives information from entity A, it can be done directly from entity B or indirectly through another entity. Entities A and B herein can be RAN nodes or terminals, or modules within a RAN node or terminal. The sending and receiving of information can be information exchange between a RAN node and a terminal, for example, between a base station and a terminal; the sending and receiving of information can also be information exchange between two RAN nodes, for example, between a CU and a DU; the sending and receiving of information can also be information exchange between different modules within a device, for example, between a terminal chip and other modules in the terminal, or between a base station chip and other modules within the base station.

[0420] It is understood that the processor in the embodiments of the present application may be a central processor unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0421] The method steps in the embodiments of the present application can be implemented in hardware or in software instructions that can be executed by a processor. The software instructions can be composed of corresponding software modules, and the software modules can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, mobile hard disks, compact disc read-only memory (CD-ROM) or any other form of storage medium well known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. The storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a base station or a terminal. The processor and the storage medium can also be present in a base station or a terminal as discrete components.

[0422] In the above embodiments, all or part of the embodiments may be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer programs or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are performed in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device, or other programmable device. The computer program or instructions may be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions may be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium may be any available medium that can be accessed by a computer, or a data storage device such as a server or data center that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; an optical medium, such as a digital video disk; or a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or nonvolatile storage medium, or may include both volatile and nonvolatile types of storage media.

[0423] Finally, regarding the embodiments of this application, there are the following points to explain:

[0424] First, in the embodiments of this application, the first, second, and various numerical numbers are merely distinctions for ease of description and are not intended to limit the scope of the embodiments of this application. For example, a first primary cell and a second primary cell represent two primary cells, which may be two different cells or the same cell.

[0425] Second, in the embodiments of the present application, "indication" may include direct indication and indirect indication, and may also include explicit indication and implicit indication. The information indicated by a certain information is called information to be indicated. In the specific implementation process, there are many ways to indicate the information to be indicated. For example, the information to be indicated can be directly indicated, such as the information to be indicated itself or the index of the information to be indicated. The information to be indicated can also be indirectly indicated by indicating other information, wherein there is an association relationship between the other information and the information to be indicated. It is also possible to indicate only a part of the information to be indicated, while the other parts of the information to be indicated are known or agreed in advance. For example, the indication of the information to be indicated can be achieved by means of a pre-agreed (such as a protocol provision) on whether a certain information element exists, thereby reducing the indication overhead to a certain extent.

[0426] Third, the "protocol" involved in the embodiments of this application may refer to a standard protocol in the communication field, for example, it may include an LTE protocol, an NR protocol, and related protocols in future communication systems, which is not limited in this application.

[0427] Fourth, "predefinition" or "preconfiguration" can be achieved by pre-saving corresponding codes, tables or other methods that can indicate relevant information in a device (for example, a terminal or base station). This application does not limit the specific implementation method. Among them, "saving" can mean saving in one or more memories, and the one or more memories can be separate settings or integrated in a processor or communication device; the one or more memories can also be partially set separately and partially integrated in a processor or communication device. The type of memory can be any form of storage medium, and this application is not limited to this.

[0428] Fifth, "at least one" means one or more, and "more" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist at the same time, where A and B can be single objects or multiple objects. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b and c can mean: a, or b, or c, or a and b, or a and c, or b and c, or a, b and c. Where a, b and c can be single objects or multiple objects respectively.

[0429] Sixth, in the embodiments of the present application, descriptions such as "when...", "in the case of...", "if" and "if" all mean that the device (for example, a terminal or base station) will perform corresponding processing under certain objective circumstances. It does not limit the time, nor does it require the device to perform a judgment action when implementing it, nor does it mean that there are other limitations.

[0430] Seventh, in the various embodiments of the present application, unless otherwise specified or provided by logic, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

Claims

1. A communication method, characterized in that, The method includes: Receiving second information via a first path, the second information including a first set and / or a second set, the first set indicating cells supporting a first handover mode, and the second set indicating cells supporting a second handover mode; Determining to switch the first path to a second path via the first handover mode or the second handover mode, the second path including a connection between the terminal and a second cell, wherein, When switching the first path to the second path via the first handover mode, the second cell belongs to the cells indicated by the first set, or the second cell does not belong to the cells indicated by the second set; or, When switching the first path to the second path via the second handover mode, the second cell belongs to the cells indicated by the second set, or the second cell does not belong to the cells indicated by the first set.

2. The method according to claim 1, characterized in that Before determining to switch the first path to the second path via the first handover mode or the second handover mode, the method further includes: Receiving third information via the first path, the third information indicating that the terminal is allowed to perform multiple handover modes, the multiple handover modes including the first handover mode and the second handover mode.

3. The method according to claim 1 or 2, characterized in that, Before receiving the second information via the first path, the method further includes: Sending fourth information via the first path, the fourth information indicating that the terminal enables the mode of performing the second handover mode.

4. The method according to any one of claims 1 to 3, characterized in that The method further includes: If it is determined to switch the first path to the second path via the second handover mode, then adjusting the signal quality value of the second cell from a first value to a second value, the first value being greater than or equal to the signal quality value corresponding to the first handover mode, and the second value being less than the signal quality value corresponding to the first handover mode; Sending the second value via the first path.

5. The method according to any one of claims 1 to 4, characterized in that, Before receiving the second information via the first path, the method further includes: Sending first information via the first path, the first information indicating that the terminal supports multiple handover modes, the multiple handover modes including the first handover mode and the second handover mode.

6. The method according to any one of claims 1 to 5, characterized in that The first handover mode is a handover mode based on cell handover, the second handover mode is a handover mode based on dual connectivity, the first set is a first cell set, the second set is a second cell set, the public land mobile network (PLMN) corresponding to the cells in the first cell set is equivalent to the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is not equivalent to the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

7. The method according to any one of claims 1 to 5, characterized in that The first handover mode is a handover mode based on cell handover, the second handover mode is a handover mode based on dual connectivity, the first set is a first PLMN set, the second set is a second PLMN set, the PLMN in the first PLMN set is equivalent to the PLMN of the first cell, the PLMN in the second PLMN set is not equivalent to the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

8. The method according to any one of claims 1 to 5, characterized in that, The first handover method is a handover method based on cell handover, the second handover method is a handover method based on dual connectivity, the first set is the first cell set, the second set is the second cell set, the PLMN corresponding to the cells in the first cell set is the same as the PLMN of the first cell, the PLMN corresponding to the cells in the second cell set is different from the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

9. The method according to any one of claims 1 to 5, characterized in that, The first handover method is a handover method based on cell handover, the second handover method is a handover method based on dual connectivity, the first set is the first PLMN set, the second set is the second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, and the first cell is the cell corresponding to the first path.

10. A communication method, characterized in that, The method includes: Receiving permission information from a core network device, the permission information indicating that the terminal is allowed to perform multiple handover methods, the multiple handover methods including the first handover method and the second handover method; or, the permission information indicating that the terminal is allowed to perform the second handover method; According to the permission information, sending second information to the terminal, the second information including the first set and / or the second set, the first set indicating the cells supporting the first handover method, and the second set indicating the cells supporting the second handover method.

11. The method according to claim 10, wherein Before receiving the permission information from the core network device, the method further includes: Receiving first information from the terminal, the first information indicating that the terminal supports multiple handover methods, the multiple handover methods including the first handover method and the second handover method; Sending the first information to the core network device.

12. The method according to claim 10 or 11, characterized in that, The method further includes: Sending third information to the terminal, the third information indicating that the terminal is allowed to perform multiple handover methods, the multiple handover methods including the first handover method and the second handover method.

13. The method according to claim 12, characterized in that, Before sending the second information to the terminal, the method further includes: Receiving fourth information from the terminal, the fourth information indicating that the terminal enables the mode of performing the second handover method; Sending the second information to the terminal includes: According to the fourth information, sending the second information to the terminal.

14. The method according to any one of claims 10 to 13, characterized in that, Sending the second information to the terminal includes: sending the second information to the terminal through the first path, where the cell corresponding to the first path is the first cell; The permission information includes at least one of the following information: Fifth information, indicating that the access network device does not perform the first handover method; Sixth information, indicating that the access network device performs the second handover method; The first Public Land Mobile Network (PLMN) set, where the PLMNs in the first PLMN set are not equivalent to the PLMN of the first cell; Seventh information, indicating that the priority of the first handover method is lower than the priority of the second handover method.

15. The method according to any one of claims 10 to 14, characterized in that The method further includes: Sending eighth information to the core network device, the eighth information indicating that the handover method configuration of the terminal has been updated.

16. The method according to any one of claims 10 to 15, characterized in that, Sending the second information to the terminal includes: sending the second information to the terminal via a first path, where the cell corresponding to the first path is a first cell; the first handover mode is a handover mode based on cell handover, the second handover mode is a handover mode based on dual connectivity, the first set is a first cell set, the second set is a second cell set, the PLMNs corresponding to the cells in the first cell set are equivalent to the PLMN of the first cell, and the PLMNs corresponding to the cells in the second cell set are not equivalent to the PLMN of the first cell.

17. The method according to any one of claims 10 to 15, characterized in that, Sending the second information to the terminal includes: sending the second information to the terminal via a first path, where the cell corresponding to the first path is a first cell; the first handover mode is a handover mode based on cell handover, the second handover mode is a handover mode based on dual connectivity, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMN of the first cell, and the PLMNs in the second PLMN set are not equivalent to the PLMN of the first cell.

18. The method according to any one of claims 10 to 15, characterized in that, Sending the second information to the terminal includes: sending the second information to the terminal via a first path, where the cell corresponding to the first path is a first cell; the first handover mode is a handover mode based on cell handover, the second handover mode is a handover mode based on dual connectivity, the first set is a first cell set, the second set is a second cell set, the PLMNs corresponding to the cells in the first cell set are the same as the PLMN of the first cell, and the PLMNs corresponding to the cells in the second cell set are different from the PLMN of the first cell.

19. The method according to any one of claims 10 to 15, characterized in that, Sending the second information to the terminal includes: sending the second information to the terminal via a first path, where the cell corresponding to the first path is a first cell; the first handover mode is a handover mode based on cell handover, the second handover mode is a handover mode based on dual connectivity, the first set is a first PLMN set, the second set is a second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, and the PLMNs in the second PLMN set do not include the PLMN of the first cell.

20. A communication method, characterized in that, The method includes: Determining permission information, where the permission information indicates that the terminal is allowed to perform multiple handover modes, and the multiple handover modes include a first handover mode and a second handover mode; or, the permission information indicates that the terminal is allowed to perform the second handover mode; Sending the permission information.

21. The method according to claim 20, characterized in that, Before determining the permission information, the method further includes: Receiving first information, where the first information indicates that the terminal supports multiple handover modes, and the multiple handover modes include the first handover mode and the second handover mode.

22. The method according to claim 20 or 21, characterized in that, The permission information includes at least one of the following information: Fifth information, indicating that the access network device does not perform the first handover mode; Sixth information, indicating that the access network device performs the second handover mode; A first set of public land mobile networks (PLMNs), where the PLMNs in the first PLMN set are not equivalent to the PLMN of the first cell, the first cell being the cell corresponding to the first path, and the first path including the connection between the terminal and the access network device; Seventh information indicating that the priority of the first handover method is lower than the priority of the second handover method.

23. The method according to any one of claims 20 to 22, characterized in that The permission information includes a first set and / or a second set, the first set indicating the PLMNs that support the first handover method, and the second set indicating the PLMNs that support the second handover method.

24. The method according to claim 23, wherein The first handover method is a cell-based handover method, the second handover method is a dual-connection-based handover method, the first set is the first PLMN set, the second set is the second PLMN set, the PLMNs in the first PLMN set are equivalent to the PLMN of the first cell, the PLMNs in the second PLMN set are not equivalent to the PLMN of the first cell, the first cell being the cell corresponding to the first path, and the first path including the connection between the terminal and the access network device.

25. The method according to claim 23, wherein The first handover method is a cell-based handover method, the second handover method is a dual-connection-based handover method, the first set is the first PLMN set, the second set is the second PLMN set, the PLMNs in the first PLMN set include the PLMN of the first cell, the PLMNs in the second PLMN set do not include the PLMN of the first cell, the first cell being the cell corresponding to the first path, and the first path including the connection between the terminal and the access network device.

26. The method according to any one of claims 20 to 25, characterized in that, The method further includes: Receiving eighth information indicating that the handover method configuration of the terminal has been updated.

27. A communication device, characterized in that, Including: A module for executing the method according to any one of claims 1 to 9, or a module for executing the method according to any one of claims 10 to 19, or a module for executing the method according to any one of claims 20 to 26.

28. A communication device, characterized in that, Including: A processor and an interface circuit, the interface circuit being configured to receive signals from other communication devices and transmit them to the processor or send signals from the processor to other communication devices, and the processor implementing, through logic circuits or by executing code instructions: the method according to any one of claims 1 to 9, or the method according to any one of claims 10 to 19, or the method according to any one of claims 20 to 26.

29. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program or instructions, and when the computer program or instructions are executed by a communication device, the method according to any one of claims 1 to 9 is implemented, or the method according to any one of claims 10 to 19 is implemented, or the method according to any one of claims 20 to 26 is implemented.

Images