WO2025213372A1 - Wireless communication method and communication device - Google Patents

Abstract

Provided are a wireless communication method and a communication device. The method comprises: a terminal device receives one or more count values sent by a first master node, wherein the one or more count values are used for determining a secondary key when the terminal device performs a first handover procedure, the secondary key is used for communication between the terminal device and a secondary node, and the first handover procedure is an MCG LTM procedure.

Description

Wireless communication method and communication device Technical Field

The present application relates to the field of communication technology, and more particularly, to a wireless communication method and a communication device.

Background Art

In the dual connection (DC) scenario, some communication systems, such as the new radio (NR) system, support master cell group L1/L2 triggered mobility (MCG LTM). How to better support the MCG LTM process is an issue that needs to be addressed.

Summary of the Invention

The present application provides a wireless communication method and a communication device. The following introduces various aspects involved in the present application.

In a first aspect, a wireless communication method is provided, comprising: a terminal device receiving one or more count values sent by a first master node;

The one or more count values are used to determine the auxiliary key when the terminal device performs the first switching process, the auxiliary key is used for the terminal device to communicate with the auxiliary node, and the first switching process is the MCG LTM process.

In a second aspect, a wireless communication method is provided, comprising: a first master node sends one or more count values to a terminal device; wherein the one or more count values are used to determine a secondary key when the terminal device performs a first switching process, the secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is an MCG LTM process.

In a third aspect, a wireless communication method is provided, comprising: a second master node sends a first message to a first master node, the first master node is a source master node of a terminal device when performing a first switching process, the second master node is a master node to which at least one candidate cell associated with the first switching process belongs, the first message includes at least one count value, the at least one count value is used to determine a secondary key associated with the at least one candidate cell, the secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is an MCG LTM process.

In a fourth aspect, a wireless communication method is provided, comprising: a secondary node receiving one or more secondary keys sent by a second primary node, the one or more secondary keys being associated with at least one candidate cell under the second primary node, or the one or more secondary keys being associated with a target cell under the second primary node, the secondary key being used by a terminal device to communicate with the secondary node after executing a first switching process, the second primary node being the primary node to which the at least one candidate cell belongs, and the first switching process being an MCG LTM process.

In a fifth aspect, a communication device is provided, which is a terminal device, and the communication device includes: a receiving unit for receiving one or more count values sent by a first master node; wherein the one or more count values are used to determine a secondary key when the terminal device performs a first switching process, and the secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is an MCG LTM process.

In the sixth aspect, a communication device is provided, which is a first master node, and the communication device includes: a first sending unit, used to send one or more count values to a terminal device; wherein the one or more count values are used to determine a secondary key when the terminal device performs a first switching process, and the secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is an MCG LTM process.

In the seventh aspect, a communication device is provided, which is a second master node, and the communication device includes: a first sending unit, used to send a first message to the first master node, the first master node is the source master node of the terminal device when performing a first switching process, the second master node is the master node to which at least one candidate cell associated with the first switching process belongs, the first message includes at least one count value, the at least one count value is used to determine the secondary key associated with the at least one candidate cell, the secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is an MCG LTM process.

In the eighth aspect, a communication device is provided, which is a secondary node, and the communication device includes: a first receiving unit, used to receive one or more secondary keys sent by a second main node, the one or more secondary keys are associated with at least one candidate cell under the second main node, or the one or more secondary keys are associated with a target cell under the second main node, the secondary key is used by the terminal device to communicate with the secondary node after executing a first switching process, the second main node is the main node to which the at least one candidate cell belongs, and the first switching process is an MCG LTM process.

In the ninth aspect, a communication device is provided, comprising a processor, a memory, and a communication interface, wherein the memory is used to store one or more computer programs, and the processor is used to call the computer program in the memory so that the communication device executes some or all of the steps described in the methods of the above aspects.

In a tenth aspect, an embodiment of the present application provides a communication system, which includes the above-mentioned communication device. In another possible design In the embodiment, the system may also include other devices that interact with the communication device in the solution provided in the embodiment of the present application.

In the eleventh aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program enables a computer to execute part or all of the steps in the methods of the above aspects.

In a twelfth aspect, embodiments of the present application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, wherein the computer program is operable to cause a computer to perform some or all of the steps of the methods described in each of the above aspects. In some implementations, the computer program product may be a software installation package.

In the thirteenth aspect, an embodiment of the present application provides a chip, which includes a memory and a processor. The processor can call and run a computer program from the memory to implement some or all of the steps described in the methods of the above aspects.

In an embodiment of the present application, when the terminal device executes the MCG LTM process, the auxiliary key can be determined based on one or more count values sent by the first master node, thereby saving signaling overhead.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is an exemplary diagram of a system architecture of a wireless communication system to which an embodiment of the present application may be applied.

Figure 2 is a schematic diagram of the LTM process.

FIG3 is a schematic diagram of key deduction during the Xn switching process.

FIG4 is a schematic diagram of key update during the Xn switching process.

FIG5 is a schematic diagram of a control plane networking method in a dual-connection scenario.

FIG6 is a schematic diagram of a user plane protocol stack on a network device side in a dual-connectivity scenario.

FIG7 is a schematic diagram of the user plane protocol stack on the terminal device side in a dual-connection scenario.

FIG8 is a schematic diagram of the implementation process of the security mechanism during the secondary node addition/modification process.

FIG9 is a flow chart of a wireless communication method provided in an embodiment of the present application.

FIG10 is a flow chart of a wireless communication method provided in another embodiment of the present application.

FIG11 is a flowchart of a wireless communication method provided in another embodiment of the present application.

FIG12 is a schematic structural diagram of a communication device provided in an embodiment of the present application.

FIG13 is a schematic structural diagram of a communication device provided in another embodiment of the present application.

FIG14 is a schematic structural diagram of a communication device provided in yet another embodiment of the present application.

FIG15 is a schematic structural diagram of a communication device provided in yet another embodiment of the present application.

FIG16 is a schematic structural diagram of a communication device provided in an embodiment of the present application.

DETAILED DESCRIPTION

Communication system architecture

FIG1 is a diagram illustrating an exemplary system architecture of a wireless communication system 100 to which embodiments of the present application may be applied. The wireless communication system 100 may include a network device 110 and a terminal device 120. The network device 110 may be a device that communicates with the terminal device 120. The network device 110 may provide communication coverage for a specific geographic area and may communicate with the terminal device 120 within the coverage area.

FIG1 exemplarily shows a network device and two terminal devices. Optionally, the wireless communication system 100 may include multiple network devices and each network device may include another number of terminal devices within its coverage area, which is not limited in this embodiment of the present application.

Optionally, the wireless communication system 100 may further include other network entities such as a network controller and a mobility management entity, which is not limited in the embodiment of the present application.

It should be understood that the technical solutions of the embodiments of the present application can be applied to various communication systems, such as the fifth generation (5G) system or NR, the long term evolution (LTE) system, the LTE frequency division duplex (FDD) system, and the LTE time division duplex (TDD) system. The technical solutions provided in this application can also be applied to future communication systems, such as the sixth generation mobile communication system and satellite communication systems.

The terminal device in the embodiments of the present application may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station (MS), mobile terminal (MT), remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device. The terminal device in the embodiments of the present application may refer to a device that provides voice and/or data connectivity to a user and can be used to connect people, objects and machines, such as a handheld device with wireless connection function, a vehicle-mounted device, etc. The terminal device in the embodiment of the present application can be a mobile phone, a tablet computer, a laptop computer, a PDA, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. Optionally, the UE can be used to act as a base station. For example, the UE It can act as a scheduling entity that provides sidelink signals between UEs in V2X or D2D, etc. For example, a cell phone and a car can communicate with each other using sidelink signals. Cell phones and smart home devices can also communicate with each other without relaying the communication signals through a base station.

The network device in the embodiments of the present application may be a device for communicating with a terminal device. The network device may also be referred to as an access network device or a radio access network device. For example, the network device may be a base station. The network device in the embodiments of the present application may refer to a radio access network (RAN) node (or device) that connects a terminal device to a wireless network. A base station may broadly cover various names as follows, or replace the following names, such as: NodeB, evolved NodeB (eNB), next generation NodeB (gNB), relay station, transmitting and receiving point (TRP), transmitting point (TP), master station MeNB, secondary station SeNB, multi-standard radio (MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmission node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), positioning node, etc. A base station may be a macro base station, a micro base station, a relay node, a donor node, or the like, or a combination thereof. The base station may also refer to a communication module, modem or chip provided in the aforementioned device or apparatus. The base station may also be a mobile switching center and a device-to-device D2D, vehicle-to-everything (V2X), machine-to-machine (M2M) communication device that performs the base station function, a network side device in a 6G network, a device that performs the base station function in a future communication system, etc. The base station may support networks with the same or different access technologies. The embodiments of the present application do not limit the specific technology and specific device form adopted by the network equipment.

Base stations can be fixed or mobile. For example, a helicopter or drone can be configured to act as a mobile base station, and one or more cells can move based on the location of the mobile base station. In other examples, a helicopter or drone can be configured to act as a device that communicates with another base station.

In some deployments, the network device in the embodiments of the present application may refer to a CU or a DU, or the network device may include a CU and a DU. The gNB may also include an AAU.

The network equipment and terminal devices can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; they can also be deployed in the air on aircraft, balloons, and satellites. The embodiments of this application do not limit the scenarios in which the network equipment and terminal devices are located.

It should be understood that all or part of the functions of the communication device in this application can also be implemented through software functions running on hardware, or through virtualization functions instantiated on a platform (such as a cloud platform).

LTM

To further shorten handover latency and ensure service continuity, the 3rd Generation Partnership Project (3GPP) supports LTM. For ease of understanding, the following describes the LTM process with reference to Figure 2.

As shown in FIG2 , the LTM process may include an LTM preparation phase, an LTM execution phase, and an LTM completion phase.

Steps S210 and S230 in FIG. 2 belong to the LTM preparation phase.

In step S210, the terminal device reports a measurement result to the network device. The measurement result may be a layer 3 measurement result. The network device may then determine to initiate an LTM process based on the measurement result reported by the terminal device and trigger candidate cell preparation.

In step S220, the network device sends a radio resource control (RRC) message containing an LTM configuration (or LTM candidate configuration) to the terminal device. For example, the network device may send an RRC reconfiguration message to the terminal device to indicate the LTM configuration. The LTM configuration sent by the network device to the terminal device may include configurations of one or more candidate cells. After receiving the LTM configuration, the terminal device may store the LTM configuration indicated by the network device.

In step S230, the terminal device sends an RRC reconfiguration complete message to the network device.

In some embodiments, referring to step S240a and step S240b, after the terminal device completes the LTM preparation phase, it may perform uplink/downlink synchronization with the candidate cell in advance to shorten the interruption delay during the switching process.

Step S250 , step S260 , and step S270 (optional) in FIG2 belong to the LTM execution phase.

In step S250, the terminal device performs layer 1 measurement on each candidate cell and reports the layer 1 measurement result to the network device. After receiving the layer 1 measurement result reported by the terminal device, the network device can determine the target cell based on the layer 1 measurement result.

In step S260, the network device sends a cell handover command to the terminal device, instructing the terminal device to switch to the target cell. For example, the network device may instruct the terminal device to switch to the target cell via a medium access control element (MAC CE). After receiving the cell handover command, the terminal device may detach from the source cell and apply the configuration of the target cell.

In some embodiments, if the terminal device does not currently have a valid timing advance (TA) or transmission configuration indicator (TCI) status flag for the target cell, the terminal device may further perform step S270 during the LTM execution phase. In step S270, the terminal device initiates a random access procedure to the target cell.

Step S280 in Figure 2 belongs to the LTM completion phase. In step S280, the terminal device indicates that the LTM is completed. For example, the terminal device may send an indication of successful LTM completion to the target cell.

Key deduction during Xn switching

To ensure communication security, key derivation is typically performed during the Xn handover process to ensure secure data transmission between the terminal device and the access and mobility management function (AMF) network element. Both the terminal device and network equipment (such as the gNB) must perform key derivation to ensure data transmission security. The following describes the key derivation process using network equipment as an example, using Figure 3 as an example. The key derivation method on the terminal device side is similar to that on the network device side and will not be further described.

As shown in Figure 3, if the next hop chaining counter (NCC) value does not change, the gNB performs horizontal derivation to update the key K _gNB . If the NCC value changes, the AMF performs vertical derivation to update the next hop (NH) parameter. Whether the NCC value changes can depend on the terminal device state. For example, if the terminal device requires handover, the NCC value is updated by 1.

For ease of presentation, the NCC value x can be denoted as NCCx. For example, an NCC value of 0 can be denoted as NCC0, an NCC value of 1 can be denoted as NCC1, and so on. The initial NH parameter is denoted as NH0, and the NH parameter obtained by the x-th vertical deduction can be denoted as NHx, such as NH1, NH2, NH3, and so on.

Horizontal derivation: Taking NCC0 as an example, the gNB can derive the initial key _KgNB based on the key _KAMF and the non-access stratum (NAS) uplink count. The initial key _KgNB serves as NH0. This NH0 is associated with NCC0 as a {NH, NCC} pair. If horizontal derivation is performed, the gNB can generate the key KNG-RAN* based on the initial key _KgNB (denoted as key _KgNB1 ), the physical cell identifier (PCI) of the cell where the terminal device is currently residing, and the carrier frequency (e.g., the downlink carrier frequency). KNG _{-RAN *} is then used as the key _KgNB2 . The key _KgNB2 is used to derive keys for data integrity protection and encryption. If horizontal derivation is continued, the gNB can derive the key KgNB3 based on the key _KgNB2 , _{the PCI of the cell where the terminal device is currently residing, and the carrier frequency. The key KgNB3 is} used to derive new keys for data integrity protection and encryption. And so on, the key K _gNB is iteratively updated to ensure communication security.

Vertical deduction: If the NCC value is updated from NCC0 to NCC1, the AMF network element performs vertical deduction to deduce NH1 based on the key K _AMF and NH0. NH1 is associated with NCC1 as a new pair {NH, NCC}, which the AMF network element uses to perform horizontal deduction based on NCC1. If NCC1 is updated to NCC2, the AMF network element continues to perform vertical deduction to deduce NH2 based on the key K _AMF and NH1. NH2 is associated with NCC2 as a new pair {NH, NCC}, which the AMF network element uses to perform horizontal deduction based on NCC2. And so on.

Key update during Xn switching

To ensure communication security, key update can be performed during the Xn handover process based on the key derivation described above. The following describes the key update process in detail, using K _gNB as the key used by the source base station (S-gNB) and K _NG-RAN* as the key used by the target base station (T-gNB), in conjunction with Figure 4.

Referring to Figure 4, in step S401, the S-gNB sends a handover request (HO request) message to the T-gNB. The handover request message includes information such as the S-gNB's derived key K _NG-RAN* , NCC, and security algorithms.

In step S402, the T-gNB uses the key K _NG-RAN* as the current key K _gNB of the target base station and associates the NCC with the K _gNB .

In step S403, the T-gNB sends a handover command (HO command) message to the terminal device (UE). The handover command message includes information such as the NCC and security algorithms.

In step S404, the UE performs key derivation based on the received NCC to obtain the key K _gNB* used by the UE.

In step S405, if the UE successfully accesses the target cell, the UE sends a handover complete (HO complete) message to the T-gNB to indicate that the handover is complete.

In step S406, after receiving the handover completion message sent by the UE, the T-gNB sends a path switch request message to the AMF.

In step S407, after receiving the path switch request message, the AMF may update the NCC to NCC+1 (NCC=NCC+1), and perform NH calculation as a new pair {NH, NCC}.

In step S408, the AMF sends a path switch acknowledgment message (path switch ack) to the T-gNB. The acknowledgment message includes the updated {NH, NCC} in step S407.

In step S409, the T-gNB stores the received {NH, NCC} for further handover.

In step S410, the UE may perform an intra-cell HO procedure in the candidate cell of the T-gNB.

It should be noted that in the above key update process, the source base station can perform the following operations:

Generate _KNG-RAN* based on the target PCI and target downlink frequency. As an example, if there is unused {NH, NCC}, the key can be derived based on NH; if there is no unused {NH, NCC}, the key is derived based on _KgNB .

The generated K _NG-RAN* and the corresponding NCC are forwarded to the target base station.

It should be noted that in the above key update process, the target base station can perform the following operations:

The target base station will use the received K _NG-RAN* as the K _gNB for communicating with the terminal device; associate the K _gNB with the NCC; include the NCC in the handover command and send it to the terminal device through the source base station; after the handover is completed, the target base station sends a path switch request to the AMF.

It should be noted that in the above key update process, the terminal device can perform the following operations:

If the NCC in the handover command is the same as the NCC value associated with the current _KgNB , _KgNB* is generated based on the _KgNB and target cell PCI and downlink frequency.

If the NCC in the handover command differs from the NCC value associated with the current _KgNB , NH is generated based on KAMF. Then, _KgNB* is generated based on NH and the target cell PCI and downlink frequency.

The UE uses the generated KgNB _* to communicate with the target base station.

Dual-connection communication scenario

The methods provided in the embodiments of the present application can be used in various DC architectures. For example, dual connectivity between a fourth-generation (4G) communication system and a fifth-generation (5G) communication system, dual connectivity between a 5G communication system and a 4G communication system, or dual connectivity between a 5G communication system and a 5G communication system, or a 5G communication system and a future communication system, where the fifth-generation communication system may also be referred to as an NR system. However, it should be understood that the methods provided in the embodiments of the present application are not limited to application in a DC architecture, and may also be applied to other system architectures, such as a single-connection architecture.

In the DC architecture, a terminal device is simultaneously connected to two cell sets. One of these cell sets is called a master cell group (MCG), which includes at least one primary cell (PCell) and, optionally, at least one secondary cell (SCell). The other cell set to which the terminal device is connected is called a secondary cell group (SCG), which includes at least one primary secondary cell (PSCell) and, optionally, at least one SCell. It should be noted that, since all cells included in MCG are usually deployed in one node, in many scenarios, the node corresponding to MCG can also be called a master node (MN); since all cells included in SCG are usually deployed in one node, in many scenarios, the node corresponding to SCG can also be called a secondary node (SN). The dual-connection architecture of NR-DC is shown in Figure 5. The terminal device communicates with MN and SN at the same time. MN and SN are connected through the Xn interface, and MN is connected to the core network device through the NG interface. Optionally, SN is also connected to the core network device through the NG interface.

It should be noted that the master node acts as the "anchor" and is responsible for exchanging control plane data with the core network. In some implementations, both control plane data and user plane data can be exchanged between the terminal device and two network nodes. For the control plane, the terminal device establishes signaling radio bearer 0 (SRB0), SRB1, and SRB2 signaling connections with the mobile node, and can also establish an SRB3 signaling connection with the node node.

In addition, each access network device in a DC has a different radio link control (RLC)/medium access control (MAC) entity. Based on the different nodes where data resides in the RLC/MAC entities of the access network devices, data radio bearers (DRBs) are classified into the following bearer types: master cell group bearer (MCG Bearer), secondary cell group bearer (SCG Bearer), and split bearer (also known as forked bearer or split bearer).

As shown in Figure 6, the primary cell group bearer (MCG Bearer) is an RLC/MAC entity for this DRB located only in the master node. For example, when a mobile node receives quality of service (QoS) flows from the core network, if the data in the QoS flows is service data corresponding to the MCG Bearer, the mobile node transmits the data processed by the MN's packet data convergence protocol (PDCP) entity to the MN's RLC entity and MAC entity for processing. For another example, when a node receives QoS flows from the core network, if the data in the QoS flows is service data corresponding to the MCG Bearer, the node transmits the data processed by the SN's PDCP entity to the MN via the interface between the MNs (e.g., Xn interface, X2 interface, or F1 interface). The data is then further processed by the MN's RLC entity and MAC entity.

Continuing with Figure 6, the secondary cell group carrying SCG Bearer means that the RLC/MAC entity of the DRB is only located in the secondary node. For example, after the MN receives QoS flows from the core network, if the data in the QoS flows is the service data corresponding to the SCG Bearer, the MN will transmit the data processed by the MN's PDCP entity to the SN through the interface between the MN and the SN (for example, the Xn interface, the X2 interface, or the F1 interface). Then, the RLC entity and MAC entity of the SN will further process the data. For another example, after the SN receives QoS flows from the core network, if the data in the QoS flows is the service data corresponding to the SCG Bearer, the SN will transmit the data processed by the SN's PDCP entity to the SN's RLC entity and MAC entity for processing.

Split Bearer means that the RLC/MAC entity of the DRB exists in both the primary node and the secondary node. For example, after the MN receives the service data corresponding to the Split Bearer from the core network, the MN transmits part of the data processed by the MN's PDCP entity to the RLC entity and MAC entity of the SN through the interface between the MN and the SN (for example, the Xn interface or the X2 interface or the F1 interface), while the other part of the data or the same data is transmitted to the RLC entity and MAC entity of the MN, so that the RLC/MAC entity of the MN and the RLC/MAC entity of the SN can process the data at the same time. For another example, after the SN receives the service data corresponding to the Split Bearer from the core network, the SN transmits part of the data processed by the SN's PDCP entity to the RLC entity and MAC entity of the MN through the interface between the MN and the SN (for example, the Xn interface or the X2 interface or the F1 interface), while the other part of the data or the same data is transmitted to the RLC entity and MAC entity of the MN. The RLC entity and MAC entity of the SN are given, and then the RLC/MAC entity of the MN and the RLC/MAC entity of the SN can process the data at the same time.

It should be noted that there is no distinction between different nodes within the terminal device, but due to the role of the cell group, it is still necessary to distinguish between MCG and SCG. The main difference between MCG and SCG comes from the different radio bearer aggregation protocol layers (i.e., the difference between RLC and MAC), as shown in Figure 7.

Security mechanism during SN addition/modification

For different types of radio bearers, PDCP layer processing and above may occur at either the mobile node (MN) or the network node (SN). For radio bearers where the PDCP layer resides on the SN side, the input factors used to generate encryption/security keys include the mobile node key (K _gNB ) and the SN counter value. The SN counter is maintained by the mobile node, for example, in a monotonically increasing manner. The SN and UE do not need to store the SN counter. The security mechanism during SN addition/modification is described in detail below, in conjunction with Figure 8.

As shown in Figure 8, in step S801, an RRC connection is established between the UE and the MN.

In step S802, the MN sends an SN addition/modification request message to the SN, which includes _KSN , terminal equipment security capabilities (UE security capabilities), and user plane (UP) security policy.

It should be understood that before the MN sends an SN add/modify request to the SN, the MN may generate K _SN based on K _gNB and the SN counter.

In step S803, SN performs capability negotiation and algorithm selection.

In step S804, the SN sends an SN addition/modification request acknowledgment message to the MN. The acknowledgment message includes the selected algorithms of the SN.

In step S805, the MN sends an RRC connection reconfiguration message to the UE. The reconfiguration message includes the SN Counter and the selected algorithms.

In some implementations, the UE may generate K _SN based on K _gNB and SN counter.

In step S806, the UE sends an RRC connection reconfiguration complete message (RRC connection reconfiguration complete) to the MN.

In step S807, the MN and the SN communicate to confirm that the SN reconfiguration is complete.

In step S808, the UE activates encryption and integrity protection.

In step S809, the SN activates ciphering and integrity protection.

In step S810, the UE performs a random access procedure in the SN cell.

It should be noted that in 3GPP Release 18 (R18), LTM only supports intra-central unit (intra-CU) LTM. Furthermore, to avoid the complex radio bearer processing caused by cell handover in DC scenarios (for example, cell handover in DC scenarios may involve changes in bearer termination, which in turn requires re-establishment of the PDCP/RLC entity of the radio bearer), R18 LTM has the following limitations: Executing MCG LTM requires releasing the SCG; executing SCG LTM cannot involve affecting the mobile node (SCG LTM without MN involvement).

It should be noted that in 3GPP release 19 (R19), the scenarios supported by LTM have been expanded. For example, LTM can support inter-central unit (inter-CU) LTM. Furthermore, when DC is not configured, priority is given to the case when CU is acting as MN when DC is not configured. As a secondary priority, support the case when NR-DC is configured and CU is acting as SN and MCG is unchanged. As a secondary priority, support the case when NR-DC is configured, CU is acting as MN and SCG is unchanged or SCG is released.

In some communication systems, the design of LTM (e.g., inter-CU LTM and intra-CU LTM) needs to consider the signaling overhead of the LTM process.

During certain MCG LTM processes (for example, inter-CU MCG LTM and intra-CU MCG LTM), the terminal device may need to communicate with a secondary node using a secondary key. In this case, determining the secondary key during MCG LTM is a challenge. Signaling overhead also needs to be considered when determining the secondary key.

In response to the above problem, in an embodiment of the present application, when the terminal device executes the MCG LTM process, the auxiliary key can be determined based on one or more count values sent by the first master node, thereby saving signaling overhead.

FIG9 is a flow chart illustrating a wireless communication method according to an embodiment of the present application. The method illustrated in FIG9 is described from the perspective of a terminal device and a first master node. The terminal device mentioned herein may be, for example, the terminal device 120 shown in FIG1 . The first master node mentioned herein may be a source master node (S-MN), which may be, for example, a gNB or an eNB.

Referring to FIG. 9 , in step S910, a terminal device receives one or more count values sent by a first master node. The one or more count values are used to determine a secondary key (SK) when the terminal device performs a first handover process, which is an MCG LTM process. The secondary key can be used to communicate between the terminal device and the secondary node.

It should be noted that the above determination of the secondary key may refer to the first determination of the secondary key, or may refer to a subsequent update of the secondary key.

In an embodiment of the present application, the one or more count values may be secondary key count values (sk-counter).

In some implementations, if the first master node is a gNB, the secondary key may be referred to as SK _gNB ; if the first master node is an eNB, the secondary key may be referred to as SK _eNB .

In some implementations, the first switching process may be used to: perform cell switching within a CU (i.e., the first switching process is intra-CU MCG LTM); or, perform cell switching between CUs (i.e., the first switching process is inter-CU MCG LTM).

In the embodiments of the present application, the above-mentioned method for determining the secondary key can also be applied to scenarios where the SCG is not released. For example, during the first handover process, the scenario where the SCG is not released may include any of the following: remaining unchanged (maintaining the current SCG); replacing with an SCG other than the current SCG; or adding an SCG other than the current SCG. Since the SCG does not need to be released, the signaling overhead caused by repeatedly providing SCG configuration can be saved.

In some implementations, after the terminal device receives one or more count values sent by the first master node, the terminal device may further determine a secondary key based on the primary key and a target count value, wherein the target count value may be a count value among the one or more count values. For example, the target count value may be a count value among the one or more count values corresponding to the target cell, or the target count value may be a count value among the one or more count values corresponding to the master node to which the target cell belongs. In other embodiments, the target count value may also be a count value corresponding to one or more candidate cells.

In some implementations, before the terminal device determines the secondary key based on the primary key and the target count value, the terminal device may generate the primary key.

In some implementations, after the terminal device receives one or more count values sent by the first master node, the terminal device may perform a target operation. The target operations mentioned here may include one or more of the following: for the first bearer, reestablish or create a new PDCP entity; for the first bearer, reestablish or create a new RLC entity; for the second bearer, reestablish or create a new PDCP entity; for the second bearer, reestablish or create a new RLC entity; delete the PDCP entity corresponding to the third bearer; delete the RLC entity corresponding to the third bearer; for the signaling radio bearer (such as SRB1, SRB2, etc.), discard the PDCP service data unit (SDU) (i.e., perform a PDCP SDU discard operation). The first bearer mentioned above is a bearer using a master key (i.e., a bearer with KeyToUse configured as master), and the second bearer is a bearer using a secondary key (i.e., a bearer with KeyToUse configured as secondary). In addition, the third bearer mentioned above satisfies: the configuration information of the third bearer is included in the configuration information of the source cell, and the configuration information of the third bearer is not included in the configuration information of the target cell.

In some implementations, the target operation may be performed if a first condition is satisfied, the first condition including a master key update and/or a PDCP termination point change. For example, the target operation includes reestablishing or creating a new PDCP entity for the first bearer and/or reestablishing or creating a new RLC entity for the first bearer. In this case, the target operation is performed if the first condition is satisfied, the first condition including the master key update and/or the PDCP termination point change.

It should be noted that the above method for determining the secondary key can also be applied to scenarios where the LTM candidate cell configuration is not released. Since the LTM candidate cell configuration can be retained by the terminal device to support the terminal device to perform continuous cell handover, the signaling overhead caused by repeatedly providing the LTM candidate cell configuration can be reduced.

The embodiments of the present application do not impose any specific restrictions on the manner in which one or more count values are carried. In some implementations, one or more count values may be carried in a handover command, which is used to instruct the terminal device to switch to the target cell (the target cell may refer to the cell that the terminal device wants to access) during the first handover process. The handover command may be an LTM cell switch command (LTM cell switch command). The handover command may be carried in a MAC CE, and therefore the handover command may sometimes be referred to as an LTM cell switch MAC CE. It should be understood that since the data volume of the one or more count values is relatively small, when the one or more count values are carried in the handover command during the first handover process, it helps to save signaling overhead.

In other implementations, one or more count values may also be carried in the first configuration information (such as LTM configuration information), and the first configuration information includes configuration information of one or more candidate cells, and the configuration information of one or more candidate cells is used for the terminal device to perform the first switching process. It should be understood that the one or more count values may be included in the LTM candidate cell configuration, for example. Since the LTM candidate cell configuration can be retained by the terminal device to support the terminal device to perform continuous cell switching. Therefore, including the one or more count values in the LTM candidate cell configuration can avoid repeated configuration of the one or more count values, thereby saving signaling overhead. The following is a detailed introduction to the carrying method of the count value with reference to examples.

The count value is carried in the switch command

In some implementations, when the count value of the secondary key is determined to be carried in a handover command, the handover command may include a count value (e.g., a target count value). For example, the one or more count values include a target count value, the target count value corresponds to the target cell, or the target count value corresponds to the master node to which the target cell belongs.

In an embodiment of the present application, when the count value is carried in the handover command, the second master node may send at least one count value to the first master node to determine the secondary key associated with at least one candidate cell. A detailed description is given below in conjunction with FIG10. It should be understood that the method shown in FIG10 is described from the perspective of the first master node and the second master node. The first master node mentioned here may be, for example, the first master node shown in FIG9. The second master node mentioned here may be a candidate master node (candidate MN, C-MN), that is, at least one candidate cell. The second master node can be, for example, a gNB or an eNB.

Referring to Figure 10, in step S1010, the second master node sends a first message to the first master node. The first master node is the source master node of the terminal device when performing a first handover process, the second master node is the master node to which at least one candidate cell associated with the first handover process belongs, the first message includes at least one count value, and the at least one count value is used to determine a secondary key associated with the at least one candidate cell. The first handover process is an MCG LTM process.

In some implementations, each candidate cell under the second master node corresponds to a count value; or, all candidate cells under the second master node correspond to a count value; or, the first message includes the count value corresponding to the target cell under the second master node.

For example, if the second master node includes 4 MCG LTM candidate cells, the first message includes a count value (sk-counter) corresponding to each candidate cell; in this implementation, the count value is configured with the MCG LTM candidate cell as the granularity (each MCG LTM candidate cell corresponds to a count value).

For example, if the second master node includes 4 LTM candidate cells, the first message contains a count value, that is, all candidate cells under the second master node correspond to the same count value; in this implementation method, the configuration granularity of the count value is each second master node (each C-MN corresponds to a count value).

In some implementations, before the first master node receives the first message sent by the second master node, it also includes: the first master node sends a second message to the second master node, and the second message is used to request the second master node to provide one or more of the following: the count value of each candidate cell under the second master node; the count value of all candidate cells under the second master node, and all candidate cells correspond to one count value; the count value of the target cell.

In some implementations, the second message includes information of the target cell. For example, the target cell information may be a target cell PCI or a target cell ID.

In some implementations, the second message is sent during the LTM preparation phase of the first switching process; or, the second message is sent in response to the terminal device successfully accessing the first master node (i.e., the terminal device successfully accesses the current first master node from other MNs); or, the second message is sent after the first master node determines the target cell and before sending the switching command.

In some implementations, the second message is sent after the first master node determines the target cell and before sending the switching command, including: the second message is sent after the CU of the first master node receives the second indication information sent by the DU of the first master node, and the second indication information includes information about the target cell.

In some implementations, after the first master node receives the first message sent by the second master node, the method further includes: the CU of the first master node sends at least one count value to the DU of the first master node.

In some implementations, the DU of the first master node is one of the following DUs: the current DU of the terminal device; the DU where the target cell is located, wherein the first switching process is used to perform inter-DU switching within the CU; all DUs under the first master node including candidate cells.

For example, the CU of the first master node may send at least one count value to the current DU of the terminal device.

For another example, when the first handover procedure is used to perform inter-DU handover within a CU, the CU of the first master node may send at least one count value to the DU where the target cell is located.

For another example, the CU of the first master node may send at least one count value to all DUs under the first master node that include candidate cells.

In some implementations, the handover command is sent if the target cell does not belong to the first master node.

In some implementations, the DU of the first master node can determine whether the target cell and the current serving cell belong to the same master node or cell group. If not, the DU of the first master node can include a count value associated with the target cell/the master node to which the target cell belongs in the switching command.

In some implementations, the DU of the first master node may send third indication information to the CU of the first master node, where the third indication information includes information about the target cell. The DU of the first master node receives feedback information regarding the third indication information sent by the CU of the first master node, where the feedback information includes one of the following: a count value corresponding to the target cell; or a count value corresponding to the master node to which the target cell belongs. In other embodiments, the feedback information may further include count values corresponding to one or more candidate cells.

In some implementations, the third indication information is sent when the target cell does not belong to the first master node.

The count value is carried in the first configuration information

In the embodiment of the present application, one or more count values can be configured in the first configuration information (e.g., LTM Config). The configuration granularity of the count value is described in detail below.

In some implementations, the count value can be configured at the granularity of a candidate master node or candidate cell group. For example, each candidate master node corresponds to a count value, or each candidate master node corresponds to a set of count values (the set of count values can be, for example, a list of count values); as another example, each candidate cell group corresponds to a count value, or each candidate cell group corresponds to a set of count values. It should be understood that each candidate cell can correspond to a candidate cell group identifier or a candidate master node identifier, and the terminal device can determine the count value based on the master node or cell group to which the target cell belongs.

In some implementations, the count value may be configured based on the granularity of the candidate cells. For example, each candidate cell corresponds to a count value; or, for another example, the configuration information of each candidate cell includes a count value.

In some implementations, the count value may be configured at the granularity of all candidate cells. For example, all candidate cells correspond to one count value, that is, all candidate cells correspond to the same count value.

In some implementations, the first configuration information may include MCG configuration information and/or SCG configuration information. In other implementations, the first configuration information may also include one or more of the following: identifiers of one or more candidate cells; identifiers of cell groups corresponding to one or more candidate cells.

In some implementations, the configuration information of the SCG includes one or more of the following: configuration information of the source SCG; configuration information of other SCGs except the configuration information of the source SCG.

In some implementations, the terminal device may determine the secondary key based on a target count value from one or more count values. The target count value mentioned herein may satisfy one of the following conditions: corresponding to a target cell from one or more candidate cells; corresponding to a master node to which the target cell belongs; belonging to a first count value set, the first count value set corresponding to the master node to which the target cell belongs (i.e., each master node corresponds to a count value set); belonging to a second count value set, the second count value set corresponding to the target cell (i.e., each candidate cell corresponds to a count value set); included in the configuration information of the target cell; being a count value corresponding to one or more candidate cells, with one count value corresponding to all candidate cells from the one or more candidate cells. Accordingly, the target count value may be determined as follows: selecting a count value corresponding to the target cell from one or more candidate cells; selecting a count value corresponding to the master node to which the target cell belongs; selecting an unused count value from the first count value set corresponding to the master node to which the target cell belongs; selecting an unused count value from the second count value set corresponding to the target cell; applying a count value from the target cell configuration information; applying a count value corresponding to one or more candidate cells, with one count value corresponding to all candidate cells from the one or more candidate cells.

In some implementations, the terminal device may send an RRC reconfiguration complete message to the target cell, which includes the target count value. This ensures that the target count values on the terminal device and the network device are consistent, thereby improving the reliability and security of data transmission.

In some implementations, when the count value is carried in the first configuration information, the switching command transmitted during the first switching process may include first indication information, and the first indication information is used to indicate one or more of the following: the terminal device needs to update the master key; the terminal device needs to update the secondary key.

As an example, for example, the first indication information is 1 bit. When the first indication information is 1, it indicates that the terminal device needs to perform a key update. In one implementation, the 1-bit first indication information can be used to instruct the terminal device to update the primary key (such as K _gNB ) and the secondary key (such as SK _gNB ); in another implementation, the 1-bit first indication information can also be used to instruct the terminal device to update only the secondary key (such as SK _gNB ).

In an embodiment of the present application, when a count value is carried in the first configuration information, the first master node may receive at least one count value sent by the second master node to determine a secondary key associated with at least one candidate cell. Referring again to FIG10 , the first master node receives a first message sent by the second master node, the second master node being the master node to which at least one candidate cell belongs, the first message including at least one count value, and the at least one count value being used to determine a secondary key associated with the at least one candidate cell.

In some implementations, each candidate cell under the second master node corresponds to a count value; or, all candidate cells under the second master node correspond to a count value; or, the first message includes the count value corresponding to the target cell under the second master node.

For example, if the second master node includes 4 MCG LTM candidate cells, the first message includes a count value (sk-counter) corresponding to each candidate cell; in this implementation, the count value is configured with the MCG LTM candidate cell as the granularity (each MCG LTM candidate cell corresponds to a count value).

For example, if the second master node includes 4 LTM candidate cells, the first message contains a count value, that is, all candidate cells under the second master node correspond to the same count value; in this implementation method, the configuration granularity of the count value is each second master node (each C-MN corresponds to a count value).

In some implementations, before the first master node receives the first message sent by the second master node, it also includes: the first master node sends a second message to the second master node, and the second message is used to request the second master node to provide one or more of the following: the count value of each candidate cell under the second master node; the count value of all candidate cells under the second master node, and all candidate cells correspond to one count value; the count value of the target cell.

In some implementations, the second message is sent during the LTM preparation phase of the first switching process; or, the second message is sent in response to the terminal device successfully accessing the first master node.

In some implementations, the at least one count value may be used to update a secondary key associated with an MCG LTM candidate cell. The secondary key may be a key of a secondary node (SN), a primary secondary cell (PSCell), or a secondary cell group (SCG). It should be understood that the SN/PSCell/SCG may be the source SN/PSCell/SCG or another SN/PSCell/SCG.

It should be understood that the configuration granularity of the count value is different, and the way in which the CU of the first master node sends the count value to the DU may be different. For example, if all candidate cells correspond to one count value, the CU of the first master node may send the one count value to the DU of the first master node. For another example, if each candidate master node/candidate cell group corresponds to one count value, the CU of the first master node may send at least one count value and the candidate master node information or primary cell group information corresponding to the at least one count value to the DU of the first master node. For another example, if each A candidate cell/target cell corresponds to a count value, and the CU of the first master node may send at least one count value and one or more candidate cell/target cell information (such as cell ID) corresponding to the at least one count value to the DU of the first master node.

In some implementations, after the second master node sends the first message to the first master node, it also includes: the second master node receives a third message sent by the first master node, and the third message includes one of the following: a master key associated with at least one candidate cell; or a master key associated with a target cell in at least one candidate cell.

In some implementations, the second master node may determine a secondary key associated with at least one candidate cell based on a primary key associated with at least one candidate cell and at least one count value; and the second master node sends the secondary key associated with at least one candidate cell to the secondary node.

In some implementations, the second master node may determine a secondary key associated with the target cell based on a primary key associated with the target cell and a count value corresponding to the target cell; and the second master node may send the secondary key associated with the target cell to the secondary node. The count value corresponding to the target cell may be, for example, one of the at least one count value.

In some implementations, each candidate cell under the second master node corresponds to a count value; or, all candidate cells under the second master node correspond to a count value.

In some implementations, before the first master node receives the first message sent by the second master node, it also includes: the first master node sends a second message to the second master node, and the second message is used to request the second master node to provide the count value of the candidate cells under the second master node (for example, it can be the count value corresponding to each candidate cell, or the count value corresponding to all cells, and all candidate cells correspond to one count value).

It should be noted that one or more count values in the embodiments of the present application can be configured in the candidate cell list or outside the candidate cell list. When the count value can be configured outside the candidate cell list, as an example, the count value can be configured in the LTM-config information element, and the specific configuration method is as follows:

Figure 11 is a schematic flow chart of a wireless communication method provided by another embodiment of the present application. The method shown in Figure 11 is described from the perspective of a second master node and a secondary node. The second master node mentioned here can be, for example, the second master node shown in Figure 10. The secondary node mentioned here can be either a gNB or an eNB.

Referring to Figure 11, in step S1110, the secondary node receives one or more secondary keys sent by the second primary node. The one or more secondary keys are associated with at least one candidate cell under the second primary node, or the one or more secondary keys are associated with a target cell under the second primary node. The secondary keys are used by the terminal device to communicate with the secondary node after executing a first handover process. The second primary node is the primary node to which the at least one candidate cell belongs, and the first handover process is an MCG LTM process.

In some implementations, the second master node may first send a secondary key corresponding to at least one candidate cell to the secondary node. After the terminal device successfully accesses the second master node or receives an instruction from the secondary node, the second master node may send fourth indication information to the secondary node, where the fourth indication information is used to instruct the secondary node to use a target secondary key from among the secondary keys associated with the at least one candidate cell.

In some implementations, the second master node may send fifth indication information to the secondary node after the terminal device successfully accesses the second master node or receives an indication from the secondary node, where the fifth indication information includes a secondary key corresponding to the target cell.

The wireless communication method of the present application is described in more detail below with reference to specific examples. It should be noted that the following examples are intended solely to help those skilled in the art understand the embodiments of the present application and are not intended to limit the embodiments of the present application to the specific numerical values or specific scenarios illustrated. Those skilled in the art can readily make various equivalent modifications or variations based on the examples provided, and such modifications or variations also fall within the scope of the embodiments of the present application.

Example 1

In Example 1, the counter value (sk-counter) is carried in the switch command (LTM cell switch command). The wireless communication method in this application is described in detail from the perspective of the network side and the terminal device (UE) side. The network side includes a candidate master node (C-MN) and a source master node (S-MN).

Network side

In Example 1, the wireless communication method on the network side may include the following steps:

Step 1.01: The C-MN sends a first message to the S-MN. The first message includes: an sk-counter associated with at least one candidate cell.

For example, the C-MN includes four MCG LTM candidate cells, and the first message includes the sk-counter corresponding to each candidate cell. In this implementation, the granularity of sk-counter configuration is for each MCG LTM candidate cell.

For example, if a C-MN includes four LTM candidate cells, the first message contains one sk-counter, meaning all candidate cells under the C-MN correspond to the same sk-counter. In this implementation, the sk-counter configuration granularity is per C-MN.

For another example, the first message includes the sk-counter corresponding to the target cell, and the target cell information is included in the second message.

In some implementations, sk-counter is used to update the key of the SN/PSCell/SCG associated with the MCG LTM candidate cell. The associated SN/PSCell/SCG can be the source SN/PSCell/SCG or other SN/PSCell/SCG.

In step 1.02, based on step 1.01, the C-MN receives a second message from the S-MN before sending the first message to the S-MN. The second message is used to request the C-MN to provide sk-counter configuration; optionally, the second message also includes target cell information, such as the target cell PCI/target cell ID.

Step 1.03: Based on step 1.02, the time period during which the S-MN sends the second message to the C-MN includes:

a) LTM preparation stage;

b) The UE successfully accesses the current MN from another MN;

c) Before LTM is triggered; for example, the S-MN-DU determines the target cell based on the L1 measurement results reported by the UE and sends a second indication message to the S-MN-CU. The second indication message includes target cell information, such as the target cell ID. After receiving the second indication message, the S-MN-CU sends a second message to the C-MN corresponding to the target cell. In another implementation, the S-MN-DU determines whether the target cell and the current serving cell belong to the same MN/cell group. If not, the S-MN-DU sends the second indication message to the S-MN-CU.

Step 1.04: Based on step 1.01, after receiving the first message, the S-MN-CU sends the sk-counter or sk-counter + candidate/target cell ID or sk-counter + candidate cell group information (corresponding to the three different configuration granularities in step 1.01) to the S-MN-DU:

For example, the S-MN-CU sends the sk-counter configuration to the currently served DU; optionally, when intra-CU inter-DU LTM occurs in the UE, the S-MN-CU sends the sk-counter configuration to the target DU.

For another example, the S-MN-CU sends the sk-counter configuration to all DUs configured with LTM candidate cells under the S-MN.

In step 1.05, based on step 1.04, the S-MN-DU determines whether the target cell and the current serving cell belong to the same MN/cell group. If not, the S-MN-DU includes the sk-counter associated with the target cell/MN to which the target cell belongs in the LTM cell switch MAC CE.

Step 1.06: Based on step 1.01, the S-MN-DU sends a third indication message to the S-MN-CU. The third indication message includes at least the candidate cell ID corresponding to the target cell. Based on the third indication message, the S-MN-CU determines whether to update the sk-counter/the sk-counter associated with the target cell and sends feedback to the S-MN-DU. Optionally, the S-MN-DU determines whether the target cell and the current serving cell belong to the same MN/cell group. If not, the S-MN-DU sends the third indication message to the S-MN-CU. If the feedback message includes the sk-counter, the S-MN-DU includes the sk-counter associated with the target cell/the MN to which the target cell belongs in the LTM cell switch MAC CE.

UE side

In Example 1, the wireless communication method on the UE side may include the following steps:

In step 1.11, the UE receives the LTM cell switch MAC CE. If the LTM cell switch MAC CE contains the sk-counter, the UE's actions include:

(1) Generate the _KgNB of the target cell and update the _SKgNB based on the _KgNB of the target cell and the received sk-counter;

(2) Update SK _gNB based on K _gNB and received sk-counter;

(3) For the bearer whose KeyToUse is configured as master, re-establish/create a new PDCP/RLC entity; optionally, perform corresponding actions when the master key needs to be updated; or when the PDCP termination point changes;

(4) For the bearer whose KeyToUse is configured as secondary, re-establish/create a new PDCP/RLC entity;

(5) deleting the PDCP/RLC entity corresponding to the first bearer, where the first bearer is included in the source configuration but not in the target configuration;

(6) For SRB, PDCP SDU discard is executed. Further, PDCP SDU discard is executed based on network instructions. Further, SRB is SRB1/SRB2.

Example 2

In Example 2, the counter value (sk-counter) is carried in the LTM configuration information. In Example 2, the wireless communication method in this application is described in detail on the network side and the terminal device (UE) side. The network side includes a candidate master node (C-MN) and a source master node (S-MN).

Network side

In Example 2, the wireless communication method on the network side may include the following steps:

Step 2.01: The S-MN sends an LTM configuration to the UE. The LTM configuration includes at least:

a) Candidate cell configuration/candidate cell ID;

b) the cell group ID corresponding to the candidate cell;

c) sk-counter configuration:

i, each candidate cell group is associated with a sk-counter or sk-counter list;

ii. Each candidate cell is associated with a sk-counter. Optionally, the sk-counter is included in the configuration of each candidate cell.

iii. sk-counter. In one implementation, the sk-counter is configured outside the candidate cell list.

In some implementations, the LTM configuration information may be an LTM-config information element, which may include the following:

Step 2.02: Before sending the LTM configuration to the UE, the S-MN receives a first message sent by the C-MN, where the first message includes: an sk-counter associated with at least one candidate cell.

For example, a C-MN includes four LTM candidate cells, and the first message includes the sk-counter corresponding to each candidate cell. It can be understood that the configuration granularity of sk-counter is per LTM candidate cell.

For example, a C-MN includes four LTM candidate cells, and the first message contains a sk-counter, that is, all candidate cells under the C-MN correspond to the same sk-counter; it can be understood that the configuration granularity of the sk-counter is per C-MN.

In step 2.03, based on step 2.02, the C-MN receives a second message from the S-MN before sending the first message to the S-MN. The second message is used to request the C-MN to provide sk-counter configuration. The time period during which the S-MN sends the second message to the C-MN includes: the LTM preparation phase.

UE side

In Example 2, the wireless communication method on the UE side may include the following steps:

In step 2.11, the UE determines the target cell by receiving the LTM cell switch MAC CE or evaluating the execution conditions of the candidate cells. If the LTM cell switch MAC CE contains key update information, or the target cell belongs to a different MN/cell group than the current serving cell, the UE's actions include:

a) Generate the target cell's _KgNB , determine the sk-counter, and update the sk- _gNB based on the target cell's _KgNB and sk-counter. Alternatively, determine the sk-counter and update the sk- _gNB based on the current _KgNB and sk-counter.

b) The method of determining the sk-counter includes one or more of the following:

i, select the sk-counter associated with the target cell;

ii. Select the sk-counter associated with the MN to which the target cell belongs;

iii. Select the first unused sk-counter from the sk-counter list associated with the MN to which the target cell belongs;

iv, apply the sk-counter in the target cell configuration;

v, apply sk-counter (corresponding to part iii of step 2.01);

c) For the bearer whose KeyToUse is configured as master, rebuild/create a new PDCP/RLC entity; optionally, perform corresponding actions when the master key needs to be updated; or when the PDCP termination point changes.

d) For the bearer whose KeyToUse is configured as secondary, re-establish/create a new PDCP/RLC entity.

e) deleting the PDCP/RLC entity corresponding to the first bearer, wherein the first bearer is included in the source configuration but not included in the target configuration.

f) For SRB, execute PDCP SDU discard. Further, execute PDCP SDU discard based on network indication. Further, SRB is SRB1/SRB2.

In step 2.12, the UE sends an RRC reconfiguration complete message to the target cell. The RRC reconfiguration complete message includes the sk-counter used.

Step 2.13, LTM cell switch MAC CE contains key update information.

For example, the LTM cell switch MAC CE includes first indication information. As an example, the first indication information can be 1 bit. When the indication information is 1, it indicates that the UE needs to perform a key update. In one implementation, the 1-bit indication information is used to instruct the UE to update the K _gNB and SK _gNB . In another implementation, the 1-bit indication information is used to instruct the UE to update the SK _gNB .

Example 3

In Example 3, the interaction between the MN and the SN is mainly involved. The MN may include, for example, a C-MN, a T-MN, etc. Specifically, the following steps may be included:

In step 3.01, the C-MN receives a third message sent by the S-MN. The third message includes key information of at least one candidate cell/target cell. The key information includes at least KNG-RAN* (the key derived by the S-MN). The C-MN generates _KSN based on the KNG-RAN* and sk-counter of the candidate cell and sends it to the SN.

In one implementation, after the UE successfully accesses or receives an indication from the S-MN, the C-MN sends fourth indication information to the SN, where the fourth indication information at least includes the K _SN corresponding to the target cell.

In another implementation, the C-MN sends a _KSN corresponding to at least one candidate cell to the SN, and after the UE successfully accesses or after the S-MN instructs, sends fourth indication information to the SN, where the fourth indication information is used to instruct the SN which _KSN to use.

In an embodiment of the present application, a candidate cell configuration may be used for a UE to execute MCG LTM. The candidate cell configuration includes an MCG configuration and, optionally, an SCG configuration. In this solution, the SCG configuration may be a source PSCell/SCG configuration (e.g., applicable to an inter-CU MCG LTM with SCG unchanged scenario) or another PSCell/SCG configuration (e.g., applicable to an inter-CU MCG LTM with SCG change scenario).

In an embodiment of the present application, in order to avoid the complexity caused by the need to simultaneously update the MN key and the SN key when executing inter-CU MCG LTM with SCG unchanged, the network can be restricted from including the SN terminated bearer configuration in the current configuration and/or LTM candidate cell configuration.

The method embodiment of the present application is described in detail above in conjunction with Figures 1 to 11. The device embodiment of the present application is described in detail below in conjunction with Figures 12 to 16. It should be understood that the description of the method embodiment corresponds to the description of the device embodiment. Therefore, for parts not described in detail, reference can be made to the above method embodiment.

FIG12 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application. The communication device 1200 shown in FIG12 may be a terminal device, and the communication device 1200 may include a receiving unit 1210. The receiving unit 1210 is configured to receive one or more count values sent by a first master node; wherein the one or more count values are used to determine a secondary key when the terminal device performs a first handover process, the secondary key being used for communication between the terminal device and the secondary node, and the first handover process being an MCG LTM process.

Optionally, the one or more count values are carried in a handover command, and the handover command is used to instruct the terminal device to switch to the target cell during the first handover process.

Optionally, the one or more count values are carried in first configuration information, and the first configuration information includes configuration information of one or more candidate cells, and the configuration information of the one or more candidate cells is used by the terminal device to perform the first switching process.

Optionally, each of the one or more candidate master nodes corresponds to a count value; or each of the one or more candidate master nodes corresponds to a set of count values; or each of the one or more candidate cells corresponds to a count value; or the configuration information of each of the one or more candidate cells includes a count value; or all of the one or more candidate cells correspond to a count value; wherein, the one or more candidate cells belong to the one or more candidate master nodes.

Optionally, the configuration information of the one or more candidate cells includes one or more of the following: configuration information of MCG; configuration information of secondary cell group SCG.

Optionally, the configuration information of the SCG includes one or more of the following: configuration information of the source SCG; configuration information of other SCGs except the configuration information of the source SCG.

Optionally, the secondary key is determined by the terminal device based on a target count value among the one or more count values, and the target count value satisfies one of the following conditions: corresponds to a target cell among the one or more candidate cells; corresponds to a master node to which the target cell belongs; belongs to a first count value set, and the first count value set corresponds to the master node to which the target cell belongs; belongs to a second count value set, and the second count value set corresponds to the target cell; is included in the configuration information of the target cell; corresponds to all candidate cells among the one or more candidate cells.

Optionally, the communication device further includes: a sending unit, configured to send an RRC reconfiguration complete message to the target cell, wherein the RRC reconfiguration complete message includes the target count value.

Optionally, the switching command transmitted during the first switching process includes first indication information, and the first indication information is used to indicate one or more of the following: the terminal device needs to update the master key; the terminal device needs to update the secondary key.

Optionally, the first configuration information further includes one or more of the following: identifiers of the one or more candidate cells; identifiers of cell groups corresponding to the one or more candidate cells.

Optionally, the communication device further includes: a determination unit, configured to determine the secondary key based on the master key and the target count value after the terminal device receives one or more count values sent by the first master node, wherein the target count value is a count value among the one or more count values.

Optionally, the communication device further includes: a generating unit, configured to generate the master key before the terminal device determines the secondary key according to the master key and the target count value.

Optionally, after the terminal device receives one or more count values sent by the first master node, the communication device also includes: the terminal device performs a target operation, and the target operation includes one or more of the following: for the first bearer, rebuilding or creating a packet data convergence protocol PDCP entity; for the first bearer, rebuilding or creating a radio link control RLC entity; for the second bearer, rebuilding or creating a PDCP entity; for the second bearer, rebuilding or creating a RLC entity; deleting the PDCP entity corresponding to the third bearer; deleting the RLC entity corresponding to the third bearer; for the signaling radio bearer, discarding the PDCP service data unit SDU; wherein, the first bearer is a bearer using a primary key, and the second bearer is a bearer using a secondary key; wherein, the configuration information of the third bearer is included in the configuration information of the source cell, and the configuration information of the third bearer is not included in the configuration information of the target cell.

Optionally, the target operation is performed when a first condition is met, where the first condition includes that a master key needs to be updated and/or a PDCP endpoint changes.

Optionally, the first switching process is used to: perform cell switching within a centralized unit CU; or perform cell switching between CUs.

Optionally, during the first switching process, the SCG of the terminal device satisfies one of the following: remains unchanged; is replaced with an SCG other than the current SCG; or, an SCG other than the current SCG is added.

Optionally, the receiving unit 1210 may be the processor 1610. The communication device 1200 may further include a transceiver 1620 and a memory 1630, as specifically shown in FIG16 .

FIG13 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application. The communication device 1300 shown in FIG13 may be a first master node, and the communication device 1300 may include a first sending unit 1310. The first sending unit 1310 is configured to send one or more count values to a terminal device; wherein the one or more count values are used to determine a secondary key when the terminal device performs a first handover process, the secondary key being used for communication between the terminal device and the secondary node, and the first handover process being an MCG LTM process.

Optionally, the one or more count values are carried in a handover command, and the handover command is used to instruct the terminal device to switch to the target cell during the first handover process.

Optionally, the communication device also includes: a first receiving unit, used to receive a first message sent by a second master node, the second master node is the master node to which at least one candidate cell belongs, the first message includes at least one count value, and the at least one count value is used to determine the secondary key associated with the at least one candidate cell.

Optionally, each candidate cell under the second master node corresponds to a count value; or, all candidate cells under the second master node correspond to a count value; or, the first message includes a count value corresponding to the target cell under the second master node.

Optionally, the communication device also includes: a second sending unit, used to send a second message to the second master node before the first master node receives the first message sent by the second master node, the second message being used to request the second master node to provide one or more of the following: the count value of each candidate cell under the second master node; the count value of all candidate cells under the second master node, each candidate cell corresponding to one count value; the count value of the target cell.

Optionally, the second message includes information of the target cell.

Optionally, the second message is sent during the LTM preparation phase of the first switching process; or, the second message is sent in response to the terminal device successfully accessing the first master node; or, the second message is sent after the first master node determines the target cell and before sending the switching command.

Optionally, the second message is sent after the first master node determines the target cell and before sending the switching command, including: the second message is sent after the centralized unit CU of the first master node receives the second indication information sent by the distributed unit DU of the first master node, and the second indication information contains the information of the target cell.

Optionally, the communication device further includes: a third sending unit, configured to send the at least one count value to the DU of the first master node using the CU after the first master node receives the first message sent by the second master node.

Optionally, the DU of the first master node is one of the following DUs: the current DU of the terminal device; the DU where the target cell is located, wherein the first switching process is used to perform inter-DU switching within the CU; the candidate cell under the first master node All DU.

Optionally, the handover command is sent when the target cell does not belong to the first master node.

Optionally, the communication device also includes: a fourth sending unit, used to use the DU to send third indication information to the CU of the first master node, the third indication information including information of the target cell; the DU of the first master node receives feedback information sent by the CU of the first master node for the third indication information, and the feedback information includes one of the following: the count value corresponding to the target cell; the count value corresponding to the master node to which the target cell belongs.

Optionally, the third indication information is sent when the target cell does not belong to the first master node.

Optionally, the one or more count values are carried in first configuration information, and the first configuration information includes configuration information of one or more candidate cells, and the configuration information of the one or more candidate cells is used by the terminal device to perform the first switching process.

Optionally, each of the one or more candidate master nodes corresponds to a count value; or each of the one or more candidate master nodes corresponds to a set of count values; or each of the one or more candidate cells corresponds to a count value; or the configuration information of each of the one or more candidate cells includes a count value; or all of the one or more candidate cells correspond to a count value; wherein, the one or more candidate cells belong to the one or more candidate master nodes.

Optionally, the configuration information of the one or more candidate cells includes one or more of the following: configuration information of MCG; configuration information of secondary cell group SCG.

Optionally, the configuration information of the SCG includes one or more of the following: configuration information of the source SCG; configuration information of other SCGs except the configuration information of the source SCG.

Optionally, the switching command transmitted during the first switching process includes first indication information, and the first indication information is used to indicate one or more of the following: the terminal device needs to update the master key; the terminal device needs to update the secondary key.

Optionally, the first configuration information further includes one or more of the following: identifiers of the one or more candidate cells; identifiers of cell groups corresponding to the one or more candidate cells.

Optionally, the communication device also includes: a second receiving unit, used to receive a first message sent by a second master node, the second master node is the master node to which at least one candidate cell belongs, the first message includes at least one count value, and the at least one count value is used to determine the secondary key associated with the at least one candidate cell.

Optionally, each candidate cell under the second master node corresponds to a count value; or, all candidate cells under the second master node correspond to a count value.

Optionally, the communication device also includes: a fifth sending unit, used to send a second message to the second master node before the first master node receives the first message sent by the second master node, and the second message is used to request the second master node to provide one or more of the following: the count value of each candidate cell under the second master node; the count value of all candidate cells under the second master node, and all candidate cells correspond to one count value; the count value of the target cell.

Optionally, the second message is sent during the LTM preparation phase of the first switching process; or, the second message is sent in response to the terminal device successfully accessing the first master node.

Optionally, the first switching process is used to: perform cell switching within a CU; or perform cell switching between CUs.

Optionally, during the first switching process, the SCG of the terminal device satisfies one of the following: remains unchanged; is replaced with an SCG other than the current SCG; or, an SCG other than the current SCG is added.

Optionally, the first sending unit 1310 may be the processor 1610. The communication device 1300 may further include a transceiver 1620 and a memory 1630, as specifically shown in FIG16 .

Figure 14 is a structural diagram of a communication device provided in an embodiment of the present application. The communication device 1400 shown in Figure 14 can be a second master node, and the communication device 1400 can include a first sending unit 1410. The first sending unit 1410 is used to send a first message to the first master node, the first master node is the source master node of the terminal device when performing the first switching process, the second master node is the master node to which at least one candidate cell associated with the first switching process belongs, the first message includes at least one count value, the at least one count value is used to determine the secondary key associated with the at least one candidate cell, the secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is an MCG LTM process.

Optionally, each candidate cell under the second master node corresponds to a count value; or, all candidate cells under the second master node correspond to a count value; or, the first message includes a count value corresponding to the target cell under the second master node.

Optionally, the communication device also includes: a first receiving unit, used to receive a second message sent by the first master node before the second master node sends the first message to the first master node, the second message being used to request the second master node to provide one or more of the following: a count value of each candidate cell under the second master node; a count value of all candidate cells under the second master node, wherein all candidate cells correspond to one count value; and a count value of the target cell.

Optionally, the second message includes information of the target cell.

Optionally, the second message is sent during the LTM preparation phase of the first switching process; or the second message is sent in response to The terminal device successfully accesses the first master node and sends the second message; or, the first master node sends the second message after determining the target cell and before sending the switching command.

Optionally, the communication device also includes: a second receiving unit, used to receive a third message sent by the first master node after the second master node sends the first message to the first master node, and the third message includes one of the following: a master key associated with the at least one candidate cell; or a master key associated with the target cell in the at least one candidate cell.

Optionally, the communication device further includes: a first determination unit, configured to determine a secondary key associated with the at least one candidate cell based on a primary key associated with the at least one candidate cell; and the second primary node sends the secondary key associated with the at least one candidate cell to the secondary node.

Optionally, the communication device further includes: a second sending unit, configured to send fourth indication information to the secondary node, wherein the fourth indication information is used to instruct the secondary node to use a target secondary key among the secondary keys associated with the at least one candidate cell.

Optionally, the communication device also includes: a second determination unit, used to determine the secondary key associated with the target cell based on the primary key associated with the target cell and the count value corresponding to the target cell; and a third sending unit, used to send the secondary key associated with the target cell to the secondary node.

Optionally, the first switching process is used to perform cell switching between centralized units CU.

Optionally, during the first switching process, the secondary cell group SCG of the terminal device satisfies one of the following: remains unchanged; is replaced with an SCG other than the current SCG; or, an SCG other than the current SCG is added.

Optionally, the first sending unit 1410 may be a processor 1610. The communication device 1400 may further include a transceiver 1620 and a memory 1630, as specifically shown in FIG16 .

Figure 15 is a structural diagram of a communication device provided in an embodiment of the present application. The communication device 1500 shown in Figure 15 can be a secondary node, and the communication device 1500 can include a first receiving unit 1510. The first receiving unit 1510 is used to receive one or more secondary keys sent by the second master node, and the one or more secondary keys are associated with at least one candidate cell under the second master node, or the one or more secondary keys are associated with the target cell under the second master node, and the secondary key is used for the terminal device to communicate with the secondary node after executing the first switching process, the second master node is the master node to which the at least one candidate cell belongs, and the first switching process is an MCG LTM process.

Optionally, the communication device further includes: a second receiving unit, configured to receive fourth indication information sent by the second master node, wherein the fourth indication information is used to instruct the secondary node to use a target secondary key among the secondary keys associated with the at least one candidate cell.

Optionally, the first switching process is used to perform cell switching between centralized units CU.

Optionally, during the first switching process, the secondary cell group SCG of the terminal device satisfies one of the following: remains unchanged; is replaced with an SCG other than the current SCG; or, an SCG other than the current SCG is added.

Optionally, the first receiving unit 1510 may be a processor 1610. The communication device 1500 may further include a transceiver 1620 and a memory 1630, as specifically shown in FIG16 .

Figure 16 is a schematic block diagram of a communication device according to an embodiment of the present application. The dashed lines in Figure 16 indicate that the unit or module is optional. Device 1600 may be used to implement the method described in the above method embodiment. Device 1600 may be a chip, a terminal device, or a network device.

The device 1600 may include one or more processors 1610. The processor 1610 may support the device 1600 to implement the method described in the above method embodiment. The processor 1610 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may be another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, etc. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

The apparatus 1600 may further include one or more memories 1620. The memories 1620 store programs that can be executed by the processor 1610, causing the processor 1610 to perform the methods described in the above method embodiments. The memories 1620 may be independent of the processor 1610 or integrated into the processor 1610.

The apparatus 1600 may further include a transceiver 1630. The processor 1610 may communicate with other devices or chips via the transceiver 1630. For example, the processor 1610 may transmit and receive data with other devices or chips via the transceiver 1630.

The present application also provides a computer-readable storage medium for storing a program. The computer-readable storage medium can be applied to a terminal device or network device provided in the present application, and the program enables a computer to execute the method performed by the terminal device or network device in each embodiment of the present application.

The present application also provides a computer program product. The computer program product includes a program. The computer program product can be applied to a terminal device or network device provided in the present application, and the program causes a computer to execute the method performed by the terminal device or network device in each embodiment of the present application.

The present application also provides a computer program. The computer program can be applied to the terminal device or network device provided in the present application, and the computer program enables the computer to execute the methods performed by the terminal device or network device in each embodiment of the present application. Law.

It should be understood that the terms "system" and "network" in this application can be used interchangeably. In addition, the terms used in this application are only used to explain the specific embodiments of this application and are not intended to limit this application. The terms "first", "second", "third", and "fourth" in the specification and claims of this application and the accompanying drawings are used to distinguish different objects rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

In the embodiments of this application, the term "indication" may refer to a direct indication, an indirect indication, or an indication of an association. For example, "A indicates B" may refer to a direct indication of B, e.g., B can obtain information through A; it may refer to an indirect indication of B, e.g., A indicates C, e.g., B can obtain information through C; or it may refer to an association between A and B.

In the embodiment of the present application, "B corresponding to A" means that B is associated with A and B can be determined based on A. However, it should be understood that determining B based on A does not mean determining B based solely on A, but B can also be determined based on A and/or other information.

In the embodiments of the present application, the term "corresponding" may indicate a direct or indirect correspondence between the two, or an association relationship between the two, or a relationship between indication and indication, configuration and configuration, etc.

In the embodiments of this application, the term "include" can refer to direct inclusion or indirect inclusion. Alternatively, the term "include" in the embodiments of this application can be replaced with "indicates" or "is used to determine." For example, "A includes B" can be replaced with "A indicates B" or "A is used to determine B."

In the embodiments of the present application, "pre-definition" or "pre-configuration" may be implemented by pre-storing corresponding codes, tables, or other methods that can be used to indicate relevant information in a device (e.g., a terminal device and a network device). The present application does not limit the specific implementation method. For example, pre-definition may refer to information defined in a protocol.

In the embodiments of the present application, the “protocol” may refer to a standard protocol in the communications field, for example, it may include an LTE protocol, an NR protocol, and related protocols used in future communication systems, and the present application does not limit this.

In the embodiments of this application, the term "and/or" is simply a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character "/" in this document generally indicates that the related objects are in an "or" relationship.

In various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

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

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented using software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be read by a computer or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a digital versatile disc (DVD)), or a semiconductor medium (e.g., a solid state disk (SSD)), etc.

The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims (118)

A wireless communication method, comprising: The terminal device receives one or more count values sent by the first master node; The one or more count values are used to determine a secondary key when the terminal device performs a first switching process, and the secondary key is used for the terminal device to communicate with the secondary node. The first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the primary cell group. The method according to claim 1 is characterized in that the one or more count values are carried in a switching command, and the switching command is used to instruct the terminal device to switch to the target cell during the first switching process. The method according to claim 1 is characterized in that the one or more count values are carried in first configuration information, the first configuration information includes configuration information of one or more candidate cells, and the configuration information of the one or more candidate cells is used by the terminal device to perform the first switching process. The method according to claim 3, characterized in that: Each of the one or more candidate master nodes corresponds to a count value; or Each of the one or more candidate master nodes corresponds to a set of count values; or Each candidate cell in the one or more candidate cells corresponds to a count value; or The configuration information of each candidate cell in the one or more candidate cells includes a count value; or All candidate cells in the one or more candidate cells correspond to a count value; The one or more candidate cells belong to the one or more candidate master nodes. The method according to claim 3 or 4, wherein the configuration information of the one or more candidate cells includes one or more of the following: MCG configuration information; Configuration information of the secondary cell group SCG. The method according to claim 5, wherein the SCG configuration information includes one or more of the following: Configuration information of the source SCG; Configuration information of other SCGs except the configuration information of the source SCG. The method according to any one of claims 3 to 6, wherein the secondary key is determined by the terminal device according to a target count value among the one or more count values, and the target count value satisfies one of the following conditions: corresponding to a target cell among the one or more candidate cells; corresponding to the master node to which the target cell belongs; Belonging to a first count value set, the first count value set corresponds to a master node to which the target cell belongs; belongs to a second count value set, and the second count value set corresponds to the target cell; included in the configuration information of the target cell; Corresponding to all candidate cells in the one or more candidate cells. The method according to claim 7, further comprising: The terminal device sends an RRC reconfiguration completion message to the target cell, where the RRC reconfiguration completion message includes the target count value. The method according to any one of claims 3 to 8, wherein the handover command transmitted during the first handover process includes first indication information, and the first indication information is used to indicate one or more of the following: The terminal device needs to update the master key; The terminal device needs to update the secondary key. The method according to any one of claims 3 to 9, wherein the first configuration information further includes one or more of the following: identifications of the one or more candidate cells; The identifier of the cell group corresponding to the one or more candidate cells. The method according to any one of claims 1 to 10, characterized in that after the terminal device receives one or more count values sent by the first master node, the method further comprises: The terminal device determines the secondary key according to the primary key and a target count value, wherein the target count value is a count value among one or more count values. The method according to claim 11, characterized in that, before the terminal device determines the secondary key based on the primary key and the target count value, the method further comprises: The terminal device generates the master key. The method according to any one of claims 1 to 12, characterized in that after the terminal device receives one or more count values sent by the first master node, the method further comprises: The terminal device performs a target operation, where the target operation includes one or more of the following: For the first bearer, reestablish or create a Packet Data Convergence Protocol (PDCP) entity; For the first bearer, reestablish or create a radio link control RLC entity; For the second bearer, re-establish or create a new PDCP entity; For the second bearer, reestablish or create a new RLC entity; Deleting the PDCP entity corresponding to the third bearer; Deleting the RLC entity corresponding to the third bearer; For signaling radio bearers, PDCP service data units (SDUs) are discarded. The first bearer is a bearer using a primary key, and the second bearer is a bearer using a secondary key; The configuration information of the third bearer is included in the configuration information of the source cell, and the configuration information of the third bearer is not included in the configuration information of the target cell. The method according to claim 13 is characterized in that the target operation is performed when a first condition is met, and the first condition includes that the master key needs to be updated and/or the PDCP endpoint changes. The method according to any one of claims 1 to 14, wherein the first switching process is used to: Perform cell switching within the centralized unit CU; or, Cell switching is performed between CUs. The method according to any one of claims 1 to 15, wherein, during the first handover process, the SCG of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A wireless communication method, comprising: The first master node sends one or more count values to the terminal device; The one or more count values are used to determine a secondary key when the terminal device performs a first switching process, and the secondary key is used for the terminal device to communicate with the secondary node. The first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the primary cell group. The method according to claim 17 is characterized in that the one or more count values are carried in a switching command, and the switching command is used to instruct the terminal device to switch to the target cell during the first switching process. The method according to claim 18, further comprising: The first master node receives a first message sent by a second master node, where the second master node is a master node to which at least one candidate cell belongs. The first message includes at least one count value, and the at least one count value is used to determine a secondary key associated with the at least one candidate cell. The method according to claim 19, characterized in that: Each candidate cell under the second master node corresponds to a count value; or, All candidate cells under the second master node correspond to a count value; or, The first message includes a count value corresponding to the target cell under the second master node. The method according to claim 19 or 20, characterized in that before the first master node receives the first message sent by the second master node, the method further comprises: The first master node sends a second message to the second master node, where the second message is used to request the second master node to provide one or more of the following: a count value of each candidate cell under the second master node; a count value of all candidate cells under the second master node, where each candidate cell corresponds to one count value; The count value of the target cell. The method according to claim 21 is characterized in that the second message includes information of the target cell. The method according to claim 21 or 22, characterized in that: The second message is sent during the LTM preparation phase of the first switching process; or, The second message is sent in response to the terminal device successfully accessing the first master node; or, The second message is sent after the first master node determines the target cell and before sending the handover command. The method according to claim 23, wherein the second message is sent after the first master node determines the target cell and before sending the handover command, comprising: The second message is sent after the centralized unit CU of the first master node receives the second indication information sent by the distributed unit DU of the first master node, where the second indication information includes the information of the target cell. The method according to any one of claims 19 to 24, characterized in that after the first master node receives the first message sent by the second master node, the method further comprises: The CU of the first master node sends the at least one count value to the DU of the first master node. The method according to claim 25, wherein the DU of the first master node is one of the following DUs: The current DU of the terminal device; the DU where the target cell is located, wherein the first handover procedure is used to perform inter-DU handover within the CU; All DUs under the first master node include candidate cells. The method according to any one of claims 18 to 26, wherein the handover command is sent when the target cell does not belong to the first master node. The method according to any one of claims 18 to 27, further comprising: The DU of the first master node sends third indication information to the CU of the first master node, where the third indication information includes information of the target cell; The DU of the first master node receives feedback information for the third indication information sent by the CU of the first master node, where the feedback information includes one of the following: The count value corresponding to the target cell; The count value corresponding to the master node to which the target cell belongs. The method according to claim 28 is characterized in that the third indication information is sent when the target cell does not belong to the first master node. The method according to claim 17 is characterized in that the one or more count values are carried in first configuration information, the first configuration information includes configuration information of one or more candidate cells, and the configuration information of the one or more candidate cells is used by the terminal device to perform the first switching process. The method according to claim 30, characterized in that: Each of the one or more candidate master nodes corresponds to a count value; or Each of the one or more candidate master nodes corresponds to a set of count values; or Each candidate cell in the one or more candidate cells corresponds to a count value; or The configuration information of each candidate cell in the one or more candidate cells includes a count value; or All candidate cells in the one or more candidate cells correspond to a count value; The one or more candidate cells belong to the one or more candidate master nodes. The method according to claim 30 or 31, wherein the configuration information of the one or more candidate cells includes one or more of the following: MCG configuration information; Configuration information of the secondary cell group SCG. The method according to claim 32, wherein the SCG configuration information includes one or more of the following: Configuration information of the source SCG; Configuration information of other SCGs except the configuration information of the source SCG. The method according to any one of claims 30 to 33, wherein the handover command transmitted during the first handover process includes first indication information, and the first indication information is used to indicate one or more of the following: The terminal device needs to update the master key; The terminal device needs to update the secondary key. The method according to any one of claims 30 to 34, wherein the first configuration information further includes one or more of the following: identifications of the one or more candidate cells; The identifier of the cell group corresponding to the one or more candidate cells. The method according to any one of claims 30 to 35, further comprising: The first master node receives a first message sent by a second master node, where the second master node is a master node to which at least one candidate cell belongs. The first message includes at least one count value, and the at least one count value is used to determine a secondary key associated with the at least one candidate cell. The method according to claim 36, characterized in that: Each candidate cell under the second master node corresponds to a count value; or, All candidate cells under the second master node correspond to a count value. The method according to claim 36 or 37, characterized in that before the first master node receives the first message sent by the second master node, the method further comprises: The first master node sends a second message to the second master node, where the second message is used to request the second master node to provide one or more of the following: The count value of each candidate cell under the second master node; a count value of all candidate cells under the second master node, where each candidate cell corresponds to one count value; The count value of the target cell. The method according to claim 38, characterized in that: The second message is sent during the LTM preparation phase of the first switching process; or, The second message is sent in response to the terminal device successfully accessing the first master node. The method according to any one of claims 17 to 39, wherein the first switching process is used to: Perform cell switching within the CU; or, Cell switching is performed between CUs. The method according to any one of claims 17 to 40, wherein, during the first handover process, the SCG of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A wireless communication method, comprising: The second master node sends a first message to the first master node, where the first master node is the source master node of the terminal device when executing the first switching process, and the second master node is the master node to which at least one candidate cell associated with the first switching process belongs. The first message includes at least one count value, and the at least one count value is used to determine the secondary key associated with the at least one candidate cell. The secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the primary cell group. The method according to claim 42, characterized in that: Each candidate cell under the second master node corresponds to a count value; or, All candidate cells under the second master node correspond to a count value; or, The first message includes a count value corresponding to the target cell under the second master node. The method according to claim 42 or 43, characterized in that, before the second master node sends the first message to the first master node, the method further comprises: The second master node receives a second message sent by the first master node, where the second message is used to request the second master node to provide one or more of the following: The count value of each candidate cell under the second master node; a count value of all candidate cells under the second master node, where each candidate cell corresponds to one count value; The count value of the target cell. The method according to claim 44 is characterized in that the second message includes information of the target cell. The method according to claim 44 or 45, characterized in that: The second message is sent during the LTM preparation phase of the first switching process; or, The second message is sent in response to the terminal device successfully accessing the first master node; or, The second message is sent after the first master node determines the target cell and before sending the handover command. The method according to any one of claims 42 to 46, characterized in that after the second master node sends the first message to the first master node, the method further comprises: The second master node receives a third message sent by the first master node, where the third message includes one of the following: The master key associated with the at least one candidate cell; or A master key associated with a target cell among the at least one candidate cell. The method according to claim 47, further comprising: The second master node determines, based on the primary key associated with the at least one candidate cell, a secondary key associated with the at least one candidate cell; The second master node sends the secondary key associated with the at least one candidate cell to the secondary node. The method according to claim 48, further comprising: The second master node sends fourth indication information to the secondary node, where the fourth indication information is used to instruct the secondary node to use a target secondary key among the secondary keys associated with the at least one candidate cell. The method according to claim 47, further comprising: The second master node determines the secondary key associated with the target cell according to the primary key associated with the target cell and the count value corresponding to the target cell; The second master node sends the secondary key associated with the target cell to the secondary node. The method according to any one of claims 42 to 50 is characterized in that the first switching process is used to perform cell switching between centralized units CU. The method according to any one of claims 42 to 51, wherein, during the first switching process, the secondary cell group (SCG) of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A wireless communication method, comprising: The secondary node receives one or more secondary keys sent by the second primary node, and the one or more secondary keys are associated with at least one candidate cell under the second primary node, or the one or more secondary keys are associated with the target cell under the second primary node. The secondary keys are used by the terminal device to communicate with the secondary node after executing the first switching process. The second primary node is the primary node to which the at least one candidate cell belongs, and the first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the primary cell group. The method according to claim 53, further comprising: The secondary node receives fourth indication information sent by the second primary node, where the fourth indication information is used to instruct the secondary node to use a target secondary key among the secondary keys associated with the at least one candidate cell. The method according to claim 53 or 54 is characterized in that the first switching process is used to perform cell switching between centralized units CU. The method according to any one of claims 53 to 55, wherein, during the first switching process, the secondary cell group (SCG) of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A communication device, characterized in that the communication device is a terminal device, and the communication device comprises: a receiving unit, configured to receive one or more count values sent by the first master node; The one or more count values are used to determine a secondary key when the terminal device performs a first switching process, and the secondary key is used for the terminal device to communicate with the secondary node. The first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the primary cell group. The communication device according to claim 57 is characterized in that the one or more count values are carried in a switching command, and the switching command is used to instruct the terminal device to switch to the target cell during the first switching process. The communication device according to claim 57 is characterized in that the one or more count values are carried in first configuration information, the first configuration information includes configuration information of one or more candidate cells, and the configuration information of the one or more candidate cells is used by the terminal device to perform the first switching process. The communication device according to claim 59, characterized in that: Each of the one or more candidate master nodes corresponds to a count value; or Each of the one or more candidate master nodes corresponds to a set of count values; or Each candidate cell in the one or more candidate cells corresponds to a count value; or The configuration information of each candidate cell in the one or more candidate cells includes a count value; or All candidate cells in the one or more candidate cells correspond to a count value; The one or more candidate cells belong to the one or more candidate master nodes. The communication device according to claim 59 or 60, wherein the configuration information of the one or more candidate cells includes one or more of the following: MCG configuration information; Configuration information of the secondary cell group SCG. The communication device according to claim 61, wherein the configuration information of the SCG includes one or more of the following: Configuration information of the source SCG; Configuration information of other SCGs except the configuration information of the source SCG. The communication device according to any one of claims 59 to 62, characterized in that the secondary key is a key of the terminal device root. Determined according to a target count value among the one or more count values, the target count value satisfies one of the following conditions: corresponding to a target cell among the one or more candidate cells; corresponding to the master node to which the target cell belongs; Belonging to a first count value set, the first count value set corresponds to a master node to which the target cell belongs; belongs to a second count value set, and the second count value set corresponds to the target cell; included in the configuration information of the target cell; Corresponding to all candidate cells in the one or more candidate cells. The communication device according to claim 63, characterized in that the communication device further comprises: The sending unit is configured to send an RRC reconfiguration complete message to the target cell, where the RRC reconfiguration complete message includes the target count value. The communication device according to any one of claims 59 to 64, wherein the handover command transmitted during the first handover process includes first indication information, and the first indication information is used to indicate one or more of the following: The terminal device needs to update the master key; The terminal device needs to update the secondary key. The communication device according to any one of claims 59 to 65, wherein the first configuration information further includes one or more of the following: identifications of the one or more candidate cells; The identifier of the cell group corresponding to the one or more candidate cells. The communication device according to any one of claims 57 to 66, characterized in that the communication device further comprises: The determination unit is configured to determine the secondary key according to the primary key and the target count value after the terminal device receives one or more count values sent by the first master node, wherein the target count value is a count value among the one or more count values. The communication device according to claim 67, characterized in that the communication device further comprises: A generating unit is configured to generate the master key before the terminal device determines the secondary key according to the master key and the target count value. The communication device according to any one of claims 57 to 68, characterized in that after the terminal device receives one or more count values sent by the first master node, the communication device further comprises: The terminal device performs a target operation, where the target operation includes one or more of the following: For the first bearer, reestablish or create a Packet Data Convergence Protocol (PDCP) entity; For the first bearer, reestablish or create a radio link control RLC entity; For the second bearer, re-establish or create a new PDCP entity; For the second bearer, reestablish or create a new RLC entity; Deleting the PDCP entity corresponding to the third bearer; Deleting the RLC entity corresponding to the third bearer; For signaling radio bearers, PDCP service data units (SDUs) are discarded. The first bearer is a bearer using a primary key, and the second bearer is a bearer using a secondary key; The configuration information of the third bearer is included in the configuration information of the source cell, and the configuration information of the third bearer is not included in the configuration information of the target cell. The communication device according to claim 69 is characterized in that the target operation is performed when a first condition is met, and the first condition includes that the master key needs to be updated and/or the PDCP endpoint changes. The communication device according to any one of claims 57 to 70, wherein the first switching process is used to: Perform cell switching within the centralized unit CU; or, Cell switching is performed between CUs. The communication device according to any one of claims 57 to 71, characterized in that, during the first switching process, the SCG of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A communication device, characterized in that the communication device is a first master node, and the communication device includes: A first sending unit, configured to send one or more count values to a terminal device; The one or more count values are used to determine a secondary key when the terminal device performs a first switching process, and the secondary key is used for the terminal device to communicate with the secondary node. The first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the primary cell group. The communication device according to claim 73, wherein the one or more count values are carried in a handover command, The switching command is used to instruct the terminal device to switch to the target cell during the first switching process. The communication device according to claim 74, characterized in that the communication device further comprises: The first receiving unit is used to receive a first message sent by a second master node, where the second master node is the master node to which at least one candidate cell belongs. The first message includes at least one count value, and the at least one count value is used to determine a secondary key associated with the at least one candidate cell. The communication device according to claim 75, characterized in that: Each candidate cell under the second master node corresponds to a count value; or, All candidate cells under the second master node correspond to a count value; or, The first message includes a count value corresponding to the target cell under the second master node. The communication device according to claim 75 or 76, characterized in that the communication device further comprises: The second sending unit is configured to send a second message to the second master node before the first master node receives the first message sent by the second master node, where the second message is used to request the second master node to provide one or more of the following: The count value of each candidate cell under the second master node; a count value of all candidate cells under the second master node, where each candidate cell corresponds to one count value; The count value of the target cell. The communication device according to claim 77 is characterized in that the second message includes information of the target cell. The communication device according to claim 77 or 78, characterized in that: The second message is sent during the LTM preparation phase of the first switching process; or, The second message is sent in response to the terminal device successfully accessing the first master node; or, The second message is sent after the first master node determines the target cell and before sending the handover command. The communication device according to claim 79, wherein the second message is sent after the first master node determines the target cell and before sending the handover command, and comprises: The second message is sent after the centralized unit CU of the first master node receives the second indication information sent by the distributed unit DU of the first master node, where the second indication information includes the information of the target cell. The communication device according to any one of claims 75 to 80, characterized in that the communication device further comprises: The third sending unit is configured to send the at least one count value to the DU of the first master node by using the CU after the first master node receives the first message sent by the second master node. The communication device according to claim 81, wherein the DU of the first master node is one of the following DUs: The current DU of the terminal device; the DU where the target cell is located, wherein the first handover procedure is used to perform inter-DU handover within the CU; All DUs under the first master node include candidate cells. The communication device according to any one of claims 74 to 82 is characterized in that the handover command is sent when the target cell does not belong to the first master node. The communication device according to any one of claims 74 to 83, characterized in that the communication device further comprises: a fourth sending unit, configured to send third indication information to the CU of the first master node by using the DU, where the third indication information includes information about the target cell; The DU of the first master node receives feedback information for the third indication information sent by the CU of the first master node, where the feedback information includes one of the following: The count value corresponding to the target cell; The count value corresponding to the master node to which the target cell belongs. The communication device according to claim 84 is characterized in that the third indication information is sent when the target cell does not belong to the first master node. The communication device according to claim 73 is characterized in that the one or more count values are carried in first configuration information, the first configuration information includes configuration information of one or more candidate cells, and the configuration information of the one or more candidate cells is used by the terminal device to perform the first switching process. The communication device according to claim 86, characterized in that: Each of the one or more candidate master nodes corresponds to a count value; or Each of the one or more candidate master nodes corresponds to a set of count values; or Each candidate cell in the one or more candidate cells corresponds to a count value; or The configuration information of each candidate cell in the one or more candidate cells includes a count value; or All candidate cells in the one or more candidate cells correspond to a count value; The one or more candidate cells belong to the one or more candidate master nodes. The communication device according to claim 86 or 87, wherein the configuration information of the one or more candidate cells includes one or more of the following: MCG configuration information; Configuration information of the secondary cell group SCG. The communication device according to claim 88, wherein the configuration information of the SCG includes one or more of the following: Configuration information of the source SCG; Configuration information of other SCGs except the configuration information of the source SCG. The communication device according to any one of claims 86 to 89, wherein the handover command transmitted during the first handover process includes first indication information, and the first indication information is used to indicate one or more of the following: The terminal device needs to update the master key; The terminal device needs to update the secondary key. The communication device according to any one of claims 86 to 90, wherein the first configuration information further includes one or more of the following: identifications of the one or more candidate cells; The identifier of the cell group corresponding to the one or more candidate cells. The communication device according to any one of claims 86 to 91, characterized in that the communication device further comprises: The second receiving unit is used to receive a first message sent by a second master node, where the second master node is the master node to which at least one candidate cell belongs, and the first message includes at least one count value, which is used to determine a secondary key associated with the at least one candidate cell. The communication device according to claim 92, wherein: Each candidate cell under the second master node corresponds to a count value; or, All candidate cells under the second master node correspond to a count value. The communication device according to claim 92 or 93, characterized in that the communication device further comprises: a fifth sending unit, configured to send a second message to the second master node before the first master node receives the first message sent by the second master node, where the second message is used to request the second master node to provide one or more of the following: The count value of each candidate cell under the second master node; a count value of all candidate cells under the second master node, where each candidate cell corresponds to one count value; The count value of the target cell. The communication device according to claim 94, characterized in that: The second message is sent during the LTM preparation phase of the first switching process; or, The second message is sent in response to the terminal device successfully accessing the first master node. The communication device according to any one of claims 73 to 95, wherein the first switching process is used to: Perform cell switching within the CU; or, Cell switching is performed between CUs. The communication device according to any one of claims 73 to 96, wherein, during the first switching process, the SCG of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A communication device, characterized in that the communication device is a second master node, and the communication device includes: The first sending unit is used to send a first message to a first master node, where the first master node is the source master node of the terminal device when executing the first switching process, and the second master node is the master node to which at least one candidate cell associated with the first switching process belongs. The first message includes at least one count value, and the at least one count value is used to determine the secondary key associated with the at least one candidate cell. The secondary key is used for the terminal device to communicate with the secondary node, and the first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the primary cell group. The communication device according to claim 98, wherein: Each candidate cell under the second master node corresponds to a count value; or, All candidate cells under the second master node correspond to a count value; or, The first message includes a count value corresponding to the target cell under the second master node. The communication device according to claim 98 or 99, characterized in that the communication device further comprises: The first receiving unit is configured to receive a message sent by the first master node before the second master node sends the first message to the first master node. The second message is used to request the second master node to provide one or more of the following: The count value of each candidate cell under the second master node; a count value of all candidate cells under the second master node, where each candidate cell corresponds to one count value; The count value of the target cell. The communication device according to claim 100 is characterized in that the second message includes information of the target cell. The communication device according to claim 100 or 101, characterized in that: The second message is sent during the LTM preparation phase of the first switching process; or, The second message is sent in response to the terminal device successfully accessing the first master node; or, The second message is sent after the first master node determines the target cell and before sending the handover command. The communication device according to any one of claims 98 to 102, characterized in that the communication device further comprises: The second receiving unit is configured to receive a third message sent by the first master node after the second master node sends the first message to the first master node, where the third message includes one of the following: The master key associated with the at least one candidate cell; or A master key associated with a target cell among the at least one candidate cell. The communication device according to claim 103, characterized in that the communication device further comprises: A first determining unit, configured to determine a secondary key associated with the at least one candidate cell according to a primary key associated with the at least one candidate cell; The second master node sends the secondary key associated with the at least one candidate cell to the secondary node. The communication device according to claim 104, characterized in that the communication device further comprises: The second sending unit is configured to send fourth indication information to the secondary node, where the fourth indication information is used to instruct the secondary node to use a target secondary key among the secondary keys associated with the at least one candidate cell. The communication device according to claim 103, characterized in that the communication device further comprises: a second determining unit, configured to determine a secondary key associated with the target cell according to the primary key associated with the target cell and a count value corresponding to the target cell; The third sending unit is configured to send the secondary key associated with the target cell to the secondary node. The communication device according to any one of claims 98 to 106 is characterized in that the first switching process is used to perform cell switching between centralized units CU. The communication device according to any one of claims 98 to 107, characterized in that, in the first switching process, the secondary cell group (SCG) of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A communication device, characterized in that the communication device is a secondary node, and the communication device includes: The first receiving unit is used to receive one or more auxiliary keys sent by the second master node, where the one or more auxiliary keys are associated with at least one candidate cell under the second master node, or the one or more auxiliary keys are associated with the target cell under the second master node, and the auxiliary keys are used by the terminal device to communicate with the auxiliary node after executing the first switching process. The second master node is the master node to which the at least one candidate cell belongs, and the first switching process is a mobility MCG LTM process triggered by layer 1/layer 2 of the master cell group. The communication device according to claim 109, characterized in that the communication device further comprises: The second receiving unit is configured to receive fourth indication information sent by the second master node, where the fourth indication information is used to instruct the secondary node to use a target secondary key among the secondary keys associated with the at least one candidate cell. The communication device according to claim 109 or 110 is characterized in that the first switching process is used to perform cell switching between centralized units CU. The communication device according to any one of claims 109 to 111, characterized in that, in the first switching process, the secondary cell group (SCG) of the terminal device satisfies one of the following: remain unchanged; Change to an SCG other than the current SCG; or, Added additional SCGs besides the current one. A communication device, characterized in that it includes a transceiver, a memory and a processor, the memory is used to store a program, and the processor is used to call the program in the memory so that the network device executes the method as described in any one of claims 1-56. A device, characterized in that it includes a processor, which is used to call a program from a memory so that the device executes the method according to any one of claims 1 to 56. A chip, characterized in that it includes a processor for calling a program from a memory so that a device equipped with the chip executes the method according to any one of claims 1 to 56. A computer-readable storage medium, characterized in that a program is stored thereon, wherein the program enables a computer to execute the method according to any one of claims 1 to 56. A computer program product, characterized in that it comprises a program, wherein the program causes a computer to execute the method according to any one of claims 1 to 56. A computer program, characterized in that the computer program enables a computer to execute the method according to any one of claims 1 to 56.