In the above first implementation, the terminal may generate the third identification information. In the above second implementation, since the second network node is configured with the second identification information, the terminal may generate the third identification information.

In this optional implementation, if the SCG recovery request message includes the first identification information, the second identification information, or the third identification information for indicating recovery of the SCG of the terminal, the terminal may determine, in the following manner, the identification information to be carried in the SCG recovery request message:

- detecting whether a number of bits that can be carried in the SCG recovery request message is greater than a second threshold;
- determining to carry the first identification information in the SCG recovery request message in a case that the number of bits that can be carried in the SCG recovery request message is greater than the second threshold; and
- determining to carry the second identification information or the third identification information in the SCG recovery request message in a case that the number of bits that can be carried in the SCG recovery request message is less than or equal to the second threshold.

Further, it is detected whether the second network node is configured with the second identification information in a case that the number of bits that can be carried in the SCG recovery request message is less than or equal to the second threshold. If the second network node is configured with the second identification information, it is determined to carry the second identification information in the SCG recovery request message. Otherwise, the terminal generates the third identification information, and it is determined to carry the third identification information in the SCG recovery request message.

- 2) The cause value for the terminal to execute the target process, where the cause value represents the MCG failure or the MCG fast recovery.

It can be learned from the above that in this embodiment of this application, the target process is triggered by the failure of the MCG of the terminal. Therefore, in a case that the SCG recovery request message includes the cause value for the terminal to execute the target process, the cause value may be directly indicated as the MCG failure (MCG failure) or the MCG fast recovery (MCG fast recovery). In this way, after acquiring the cause value, the first network node can learn that the SCG recovery request message is used for requesting to recover the at least one of the SCG and the MCG of the terminal.

In this optional implementation, the SCG recovery process may be implemented by a RACH process or a scheduling request (SR) process, but this application is not limited thereto. Further, the RACH process can be a 4-step RACH process or a 2-step RACH process.

If the SCG recovery process is recovered through the RACH process, the SCG recovery request message may be carried in a message (Msg) 3 of the 4-step RACH process in the 4-step RACH process, and the SCG recovery request message may be carried in an MsgA of the 2-step RACH process in the 2-step RACH process. If the SCG recovery process is recovered through the SR process, the SCG recovery request message may be carried in an SR request message of the SR process.

It can be seen that in the above manner, the terminal can request to recover the at least one of the SCG and the MCG of the terminal by transmitting the SCG recovery request message to the first network node, which specifies the process of recovering the at least one of the SCG and the MCG of the terminal.

In this embodiment of this application, optionally, after the transmitting an SCG recovery request message to a first network node, the method further includes:

- receiving a response message for the SCG recovery request message transmitted by the first network node, where
- the response message carries at least one of SCG configuration information or MCG configuration information.

During specific implementation, the first network node may transmit the response message for the SCG recovery request message to the terminal after receiving the SCG recovery request message from the terminal, to indicate whether the terminal is allowed to recover the at least one of the SCG and the MCG.

If the SCG recovery process is recovered through the RACH process, the response message may be carried in an Msg4 of the 4-step RACH process in the 4-step RACH process, and the response message may be carried in an MsgB of the 2-step RACH process in the 2-step RACH process. If the SCG recovery process is recovered through the SR process, the response message may be carried in an SR response request message of the SR process.

In actual application, the response message transmitted by the first network node may indicate that the terminal is allowed to recover the at least one of the SCG and the MCG, or may indicate that the terminal is not allowed to recover the at least one of the SCG and the MCG. In addition, in a case that the SCG recovery request is used for requesting to recover the SCG and the MCG of the terminal, the response message may indicate that the terminal is allowed to recover only the SCG or the MCG.

In this optional implementation, the response message carries at least one of the SCG configuration information and the MCG configuration information, indicating that the response message transmitted by the first network node may indicate that the terminal is allowed to recover the at least one of the SCG and the MCG. It should be understood that, if the first network node does not allow the terminal to recover the cell group the terminal requested to recover, the response message may not include the SCG configuration information or the MCG configuration information.

During specific implementation, the SCG configuration information includes at least a PSCell configuration. Further, the SCG configuration information may further include at least one SCell configuration. The MCG configuration information includes at least a PCell configuration and. Further, the MCG configuration information may further include at least one SCell configuration.

It should be noted that the PSCell configuration included in the SCG configuration information may be the same as or different from a PSCell configuration of the SCG suspended by the terminal. The SCell configuration included in the SCG configuration information may be the same as or different from an SCell configuration of the SCG suspended by the terminal. The PCell configuration included in the MCG configuration information may be the same as or different from a PCell configuration of the MCG suspended by the terminal. The SCell configuration included in the MCG configuration information may be the same as or different from an SCell configuration of the MCG suspended by the terminal.

The PSCell configuration included in the SCG configuration information is used as an example below for description.

Further, in a case that the PSCell configuration included in the SCG configuration information is different from the PSCell configuration of the SCG suspended by the terminal, the PSCell configuration included in the SCG configuration information may be a complete PSCell configuration. In this case, the terminal may directly recover the SCG according to the PSCell configuration included in the SCG configuration information. Alternatively, the PSCell configuration included in the SCG configuration information may be a varying value of the PSCell configuration. In this case, the terminal needs to recover the SCG according to the PSCell configuration included in the SCG configuration information and the PSCell configuration of the SCG suspended by the terminal.

It should be understood that the implementation principles of the above example are applicable to the SCell configuration in the SCG configuration information and the PCell configuration and the SCell configuration in the MCG configuration information. In order to avoid repetition, details are not described herein.

In this embodiment of this application, optionally, after the receiving SCG recovery configuration information transmitted by the first network node, the method further includes:

- transmitting a target message, where the target message is any one of:
- the target message is a first SCG recovery completion message in a case that the response message includes the MCG configuration information and the SCG configuration information, where the first SCG recovery completion message is used for indicating a success of SCG recovery of the terminal, and is further used for indicating a success or a failure of MCG recovery of the terminal;
- the target message is a second SCG recovery completion message in a case that the response message includes the SCG configuration information, where the second SCG recovery completion message is used for indicating a success of the SCG recovery of the terminal, and is further used for indicating a failure of the MCG recovery of the terminal; or
- the target message is an SCG recovery failure message in a case that the response message includes the MCG configuration information, where the SCG recovery failure message is used for indicating a failure of the SCG recovery of the terminal, and is further used for indicating a success or a failure of the MCG recovery.

This optional implementation is applicable to the target process being used for requesting to recover the SCG and the MCG of the terminal, but this application is not limited thereto.

The target message is detailed as follows:

Case I: The response message includes the MCG configuration information and the SCG configuration information.

In Case I, since the response message includes the MCG configuration message, the MCG recovery of the terminal may succeed or fail, and the terminal may indicate a success or a failure of the MCG recovery of the terminal through the first SCG recovery completion message.

During specific implementation, the first SCG recovery completion message may include the following implementations:

- Implementation 1: The first SCG recovery completion message is used for indicating a success of the SCG recovery and the MCG recovery of the terminal.
- Implementation 2: The first SCG recovery completion message is used for indicating a success of the SCG recovery of the terminal, and is further used for indicating a success or a failure of the MCG recovery of the terminal.

For implementation 1, the success of the MCG recovery of the terminal may be indicated implicitly or explicitly through the first SCG recovery completion message. Detailed description is as follows:

In a case that the success of the MCG recovery of the terminal is indicated explicitly through the first SCG recovery completion message, the first SCG recovery completion message may include a first indicator field used for indicating the success of the MCG recovery of the terminal. In this way, the network side may determine that the MCG recovery of the terminal succeeds after acquiring the first indicator field.

In a case that the success of the MCG recovery of the terminal is indicated implicitly through the first SCG recovery completion message, a receipt of the first SCG recovery completion message by the network side is considered as the success of the MCG recovery of the terminal. Thus, the first indicator field does not need to be carried, which reduces the signaling overheads.

For implementation 2, the success or failure of the MCG recovery of the terminal may be indicated explicitly through the first SCG recovery completion message. Detailed description is as follows:

The first SCG recovery completion message may include a second indicator field used for indicating the success or failure of the MCG recovery of the terminal. Alternatively, the second indicator field is used for indicating the success of the MCG recovery of the terminal in a case that a value of the second indicator field is a first value, and the second indicator field is used for indicating the failure of the MCG recovery of the terminal in a case that the value of the second indicator field is a second value. In this way, the network side may determine whether the MCG recovery of the terminal succeeds or fails according to the acquired value of the second indicator field.

Case II: The response message includes the SCG configuration information.

In Case II, since the response message does not include the MCG configuration information, indicating that the first network node rejects the recovery of the MCG of the terminal, the terminal may indicate a failure of the MCG recovery of the terminal through the second SCG recovery completion message.

During specific implementation, the failure of the MCG recovery of the terminal may be explicitly indicated through the second SCG recovery completion message. For example, the second SCG recovery completion message may include a third indicator field used for indicating the failure of the MCG recovery of the terminal. In this way, the network side may determine that the MCG recovery of the terminal fails after obtaining the third indicator field.

Case III: The response message includes the MCG configuration information.

In Case III, since the response message includes the MCG configuration message, the MCG recovery of the terminal may succeed or fail, and the terminal may indicate a success or a failure of the MCG recovery of the terminal through the SCG recovery failure message.

During specific implementation, the SCG recovery failure message may include the following implementations.

- Implementation 1: The SCG recovery failure message is used for indicating the failure of the SCG recovery and the MCG recovery of the terminal.
- Implementation 2: The SCG recovery failure message is used for indicating the failure of the SCG recovery of the terminal, and is further used for indicating the success or the failure of the MCG recovery of the terminal.

For implementation 1, the success of the MCG recovery of the terminal may be indicated implicitly or explicitly through the SCG recovery failure message. Detailed description is as follows:

In a case that the failure of the MCG recovery of the terminal is indicated explicitly through the SCG recovery failure message, the SCG recovery failure message may include a fourth indicator field used for indicating the failure of the MCG recovery of the terminal. In this way, the network side may determine that the MCG recovery of the terminal fails after acquiring the fourth indicator field.

In a case that the success of the MCG recovery of the terminal is indicated implicitly through the SCG recovery failure message, a receipt of the SCG recovery failure message by the network side is considered as the failure of the MCG recovery of the terminal. Thus, the fourth indicator field does not need to be carried, which reduces the signaling overheads.

For implementation 2, the success or failure of the MCG recovery of the terminal may be indicated explicitly through the SCG recovery failure message. Detailed description is as follows:

The SCG recovery failure message may include a fifth indicator field used for indicating the success or the failure of MCG recovery of the terminal. Alternatively, the fifth indicator field is used for indicating the success of the MCG recovery of the terminal in a case that a value of the second indicator field is a first value, and the fifth indicator field is used for indicating the failure of the MCG recovery of the terminal in a case that the value of the second indicator field is a second value. In this way, the network side may determine whether the MCG recovery of the terminal succeeds or fails according to the acquired value of the fifth indicator field.

In this embodiment of this application, the terminal may transmit the target message to at least one of the first network node and an MN corresponding to the terminal. For ease of understanding, detailed description is as follows:

Optionally, the transmitting a target message includes:

- transmitting the target message to the first network node.

Optionally, the transmitting a target message includes any one of:

- 1) transmitting, through the first network node, the target message to a master node (MN) corresponding to the terminal; or
- 2) directly transmitting the target message to the MN corresponding to the terminal.

In scenario 1), after receiving the SCG recovery completion message transmitted by the terminal, the first network node may forward the received SCG recovery completion message to the MN corresponding to the terminal through an interface such as Xn, and the terminal does not need to communicate with the corresponding MN. In scenario 2), the terminal may directly transmit the target message to the corresponding MN, and the first network node does not need to communicate with the MN corresponding to the terminal.

It should be noted that the second network node and the first network node in this embodiment of this application may be a same network node or different network nodes. This is determined according to an actual situation, and is not limited in this embodiment of this application.

The second network node may be an MN corresponding to the terminal or an SN corresponding to the terminal before the terminal suspends the SCG. The first network node may be the SN corresponding to the terminal before the terminal suspends the SCG or a network node of a cell group in a cell list indicated by the second network node.

Optionally, the first network node may be a network node of any one of:

- any cell group in a first cell list;
- a first cell group in the first cell list, where a primary secondary cell (PSCell) included in the first cell group satisfies a cell quality threshold;
- a second cell group in the first cell list, where a PSCell included in the second cell group is a PSCell having the best cell quality from candidate PSCells included in the first cell list; or
- a third cell group corresponding to a secondary node (SN) before the SCG of the terminal is suspended, where
- each of the cell groups includes at least a PSCell.

The first cell list may include at least one PSCell identifier. Each PSCell identifier corresponds to at least one Scell identifier. The each cell group may include one PSCell and one or more Scell identifiers corresponding to the PSCell.

In a case that at least two PSCells in the first cell list satisfy the cell quality threshold, the first cell group may be any cell group including any one of the at least two PSCells.

For ease of understanding, an example is illustrated as follows:

It is assumed that the first cell list includes a PSCell identifier a (identifying a PSCell1), a PSCell identifier b (identifying a PSCell2), and a PSCell identifier c (identifying a PSCell3). The PSCell1 and the PSCell2 satisfy the cell quality threshold. Cell quality of the PSCell2 is better than those of the PSCell1 and the PSCell3. The PSCell3 is a PSCell corresponding to the SN before the terminal suspends the SCG.

Therefore, in a case that the first network node is a network node of any cell group in the first cell list, the first network node may be a network node of any cell group including the PSCell1, the PSCell2, or the PSCell3.

In a case that the first network node is a network node of the first cell group, the first network node may be a network node of any cell group including the PSCell1 or the PSCell.

In a case that the first network node is a network node of the second cell group, the first network node may be a network node of any cell group including the PSCell2.

In a case that the first network node is a network node of the third cell group, the first network node may be a network node of any cell group including the PSCell3.

It should be noted that the first cell list and the cell quality threshold can be configured by the second network node, but this application is not limited thereto. The cell quality threshold may be determined through any one of the following parameters (but the parameters are not limited to the following): a reference signal received power (Reference Signal Received Power, RSRP), reference signal received quality (Reference Signal Received Quality, RSRQ), or a signal-to-noise and interference ratio (Signal-to-Noise and Interference Ratio, SINR).

In this embodiment of this application, optionally, when the secondary cell group (SCG) of the terminal is in the suspended state, before the SCG of the terminal is recovered by using the target resource, the method further includes:

- receiving SCG suspension configuration information transmitted by a second network node.

Further, the SCG suspension configuration information includes at least one of:

- first identification information for indicating recovery of the SCG of the terminal;
- second identification information for indicating recovery of the SCG of the terminal, where the second identification information is obtained by truncating the first identification information;
- a first cell list for indicating recovery of the SCG of the terminal; or
- a cell quality threshold for indicating recovery of the SCG of the terminal.

It should be noted that for description of the first identification information, the second identification information, the first cell list, and the cell quality threshold, refer to the above description, which is not repeated herein.

Further, the first identification information includes at least one of:

- a cell-radio network temporary identifier (C-RNTI) used by the terminal in the master cell group (MCG);
- a C-RNTI used by the terminal in the SCG; or
- a resume ID (resume ID) of context information of the SCG of the terminal.

The second identification information may be a truncated resume ID (truncated resume ID) of the context information of the SCG of the terminal. Similarly, the above third identification information may be considered as the truncated resume ID of the context information of the SCG of the terminal.

In this embodiment of this application, the SCG suspension configuration information may be used for at least one of:

- indicating configuration of the SCG of the terminal in the suspended state; or
- indicating recovery of relevant information of the SCG by the terminal.

In a case that the SCG suspension configuration information is used for indicating configuration of the SCG of the terminal in the suspended state, the terminal may configure the SCG in the suspended state in a case that the terminal receives the SCG suspension configuration information. In this way, fast suspension of the SCG of the terminal can be realized, which can reduce the power consumption of the terminal.

In a case that the SCG suspension configuration information is used for indicating recovery of relevant information of the SCG by the terminal, the trigger condition that triggers the SCG of the terminal into the suspended state is not receipt of the SCG suspension configuration information by the terminal, but the terminal may recover the at least one of the SCG and the MCG of the terminal according to the configuration content of the SCG suspension configuration information. In this way, fast recovery of the cell group can be realized, which can satisfy the transmission requirement of the terminal for a large data volume.

In a case that the SCG suspension configuration information is used not only for indicating configuration of the SCG of the terminal in the suspended state but also for indicating recovery of relevant information of the SCG by the terminal, the terminal may configure the SCG in the suspended state after receiving the SCG suspension configuration information. That is to say, the trigger condition that triggers the SCG of the terminal into the suspended state is the receipt of the SCG suspension configuration information by the terminal. Further, the SCG suspension configuration information may be stored, and then the at least one of the SCG and the MCG of the terminal may be recovered according to the configuration content of the SCG suspension configuration information. In this way, not only fast suspension of the SCG of the terminal can be realized, which can reduce the power consumption of the terminal, but also fast recovery of the cell group can be realized, which can satisfy the transmission requirement of the terminal for a large data volume.

It should be noted that the embodiments of this application may further protect an SCG processing method, which is applied to a terminal and may include:

- configuring an SCG of the terminal in a suspended state in a case that SCG suspension configuration information is received.

Optionally, after the configuring an SCG of the terminal in a suspended state, the method may further include:

- executing a target process in response to a master cell group (MCG) of the terminal failing, where the target process is used for requesting to recover at least one of the SCG and an MCG of the terminal.

A main difference between the SCG processing method and the SCG processing method in the method embodiment in FIG. 2 are is that the SCG processing method focuses on how the terminal suspends the SCG while the processing method in the method embodiment in FIG. 2 focuses on how the terminal triggers the target process.

FIG. 3 is a second flowchart of a cell group processing method according to an embodiment of this application. The cell group processing method in this embodiment of this application is applied to a first network node.

As shown in FIG. 3, the cell group processing method applied to the first network node may include the following steps:

Step 301: Execute a target process in response to a master cell group (MCG) of a terminal failing in a case that a secondary cell group (SCG) of the terminal is in a suspended state, where the target process is used for recovering at least one of the SCG and the MCG of the terminal.

In the cell group processing method in this embodiment, when the secondary cell group (SCG) of the terminal is in the suspended state, the SCG of the terminal is recovered by using a target resource. It can be learned that the embodiments of this application resolve the problem regarding the cell group recovery if the MCG fails again when the SCG is in the suspended state, which can satisfy the transmission requirement of the terminal for a large data volume.

Optionally, the target process is any one of a radio resource control (RRC) reestablishment process or an SCG recovery process.

Optionally, in a case that the target process is the SCG recovery process, the executing a target process includes:

- receiving an SCG recovery request message transmitted by the terminal, where the SCG recovery request message includes at least one of first identification information, second identification information, or third identification information for indicating recovery of the SCG of the terminal; or a cause value for the terminal to perform the target process, where the cause value represents an MCG failure or MCG fast recovery; and
- the second identification information is obtained by a second network node by truncating the first identification information, and the third identification information is obtained by the terminal by truncating the first identification information.

Optionally, after the receiving an SCG recovery request message transmitted by the terminal, the method further includes:

- transmitting a response message for the SCG recovery request message to the terminal, where
- the response message carries at least one of SCG configuration information or MCG configuration information.

Optionally, after the transmitting a response message for the SCG recovery request message to the terminal, the method further includes:

- receiving a target message transmitted by the terminal, where the target message is any one of:
- the target message is a first SCG recovery completion message in a case that the response message includes the MCG configuration information and the SCG configuration information, where the first SCG recovery completion message is used for indicating a success of SCG recovery of the terminal, and is further used for indicating a success or a failure of MCG recovery of the terminal;
- the target message is a second SCG recovery completion message in a case that the response message includes the SCG configuration information, where the second SCG recovery completion message is used for indicating a success of the SCG recovery of the terminal, and is further used for indicating a failure of the MCG recovery of the terminal; or
- the target message is an SCG recovery failure message in a case that the response message includes the MCG configuration information, where the SCG recovery failure message is used for indicating a failure of the SCG recovery of the terminal, and is further used for indicating a success or a failure of the MCG recovery.

Optionally, after the receiving a target message transmitted by the terminal, the method further includes:

- transmitting the target message to a master node (MN) corresponding to the terminal.

Optionally, the receiving a target message transmitted by the terminal includes any one of:

- receiving an SCG recovery completion message transmitted by the terminal in a case that the response message includes the MCG configuration information and the SCG configuration information; or
- receiving an SCG recovery completion message transmitted by the terminal in a case that the response message includes at least the SCG configuration information, where the SCG recovery completion message is further used for indicating a success or a failure of the MCG recovery.

Optionally, the first network node is a network node of any one of:

- any cell group in a first cell list;
- a first cell group in the first cell list, where a primary secondary cell (PSCell) included in the first cell group satisfies a cell quality threshold;
- a second cell group in the first cell list, where a PSCell included in the second cell group is a PSCell having the best cell quality from candidate PSCells included in the first cell list; or
- a third cell group corresponding to a secondary node (SN) before the SCG of the terminal is suspended, where
- each of the cell groups includes at least a PSCell.

It should be noted that this embodiment is used as the implementation of the first network node corresponding to the method embodiment of FIG. 2. Therefore, for this implementation, refer to the relevant description in the above method embodiment. In addition, the same beneficial effect can be achieved. In order to avoid repeated description, details are not described herein.

FIG. 4 is a third flowchart of a cell group processing method according to an embodiment of this application. The cell group processing method in this embodiment of this application is applied to a second network node.

As shown in FIG. 4, the cell group processing method applied to the second network node may include the following steps:

Step 401: Transmit SCG suspension configuration information to a terminal.

In this embodiment of this application, the SCG suspension configuration information may be used for at least one of:

- indicating configuration of the SCG of the terminal in the suspended state; or indicating recovery of relevant information of the SCG by the terminal.

For a function of the SCG suspension configuration information, refer to the description in the method embodiment of FIG. 2, and the details are not described herein.

According to the cell group processing method in this embodiment, the SCG suspension configuration information is transmitted to the terminal, so that at least one of the following can be realized: fast suspension of the SCG of the terminal, which can reduce the power consumption of the terminal, or fast recovery of the SCG of the terminal, which can satisfy the transmission requirement of the terminal for a large data volume.

Optionally, the SCG suspension configuration information includes at least one of:

- first identification information for indicating recovery of the SCG of the terminal;
- second identification information for indicating recovery of the SCG of the terminal, where the second identification information is obtained by truncating the first identification information;
- a first cell list for indicating recovery of the SCG of the terminal; or
- a cell quality threshold for indicating recovery of the SCG of the terminal.

Optionally, the first identification information includes at least one of:

- a cell-radio network temporary identifier (C-RNTI) used by the terminal in the master cell group (MCG);
- a C-RNTI used by the terminal in the SCG; or
- a resume ID of context information of the SCG of the terminal.

It should be noted that this embodiment is used as the implementation of the second network node corresponding to the method embodiment of FIG. 2. Therefore, for this implementation, refer to the relevant description in the above method embodiment. In addition, the same beneficial effect can be achieved. In order to avoid repeated description, details are not described herein.

It should be noted that the plurality of optional implementations described in the embodiments of this application may be implemented in combination with each other or implemented separately, which is not limited in the embodiments of this application.

For the convenience of understanding, examples are as follows:

The cell group processing method in this example may include the following steps:

- Step I: UE is in an RRC connected state and operates in an MR-DC mode.
- Step II: An MN or an SN transmits an RRC message to the UE to configure an SCG of the UE in a suspended state. Details are as follows:

The RRC message carries SCG suspension configuration. Configuration content of the SCG suspension configuration includes at least one of:

- identification information for recovering the SCG, such as a C-RNTI used by the UE in an MCG and/or the SCG, a resume ID for distinguishing a context of the SCG of the UE, or a truncated resume ID for distinguishing the context of the SCG of the UE
- a cell list for recovering the SCG, including at least one PSCell identifier, where each PSCell may have one or more SCell identifiers; or
- a cell quality threshold (RSRP, RSRQ, and SINR) for recovering the SCG.
- Step III: The UE stores a received SCG suspension configuration.
- Step IV: The UE determines whether an MCG fails, and performs step V or step VI if a condition for an MCG failure is satisfied.
- Step V: Trigger an RRC reestablishment process.
- Step VI: Trigger an SCG recovery process. Details are as follows:

The UE transmits an SCG recovery request message to a network node. The SCG recovery request message carries the following:

- identification information for recovering the SCG, where the identification information for recovering the SCG is the configuration of step II or the truncated identification information generated by the UE according to the configuration of step II; and
- a cause for initiating the SCG recovery request, where a new cause value is defined as an MCG failure or MCG fast recovery.

Due to mobility of the UE, the network node herein and the SN in step II may be a same node or different nodes. Specifically, the network node may be:

- a group (a PSCell or an SCell) of the SCG suspension configuration in step II;
- a group (a PSCell or an SCell) of the SCG suspension configuration in step II satisfying the cell quality threshold;
- a group (a PSCell or an SCell) of the SCG suspension configuration in step II having the best cell quality; and
- (a PSCell or an SCell) corresponding to the SN in step II.

The network node feeds back an SCG recovery configuration message to the UE, where the SCG recovery configuration message carries MCG configuration and SCG configuration.

The UE transmits an SCG recovery completion message to the network node.

After the UE recovers the SCG, the network node notifies the MN of “SCG recovery success” through an Xn interface, or the UE directly notifies the MN of “SCG recovery success”.

The UE directly notifies the MN of “MCG recovery success”.

In this example, since the MCG fails (failure) when the SCG is suspended (suspend), the UE determines to perform reestablishment, or triggers the SCG and the MCG fast recovery process. It can be learned that this example can quickly recover the MCG and the SCG simultaneously when the terminal SCG is suspended and the MCG fails, which reduces the signaling delay.

This example may be applied to an MR-DC scenario.

It should be noted that the cell group processing method provided in this embodiment of this application may be performed by a cell group processing apparatus or by a control module in the cell group processing apparatus configured to perform the cell group processing method.

The cell group processing apparatus in this embodiment of this application may be an apparatus or a component, an integrated circuit, or a chip in a communication device. The communication device may be a terminal, a first network node, or a second network node. The cell group processing apparatus in this embodiment of this application may be an apparatus having an operating system. The operating system may be Android (Android), IOS, or other possible operating systems, which is not specifically defined in this embodiment of this application.

FIG. 5 is a structural diagram of a cell group processing apparatus according to an embodiment of this application. The cell group processing apparatus 500 shown in FIG. 5 may be applied to a terminal.

As shown in FIG. 5, the cell group processing apparatus 500 includes:

- a first execution module 501, configured to execute a target process in response to a master cell group (MCG) of the terminal failing in a case that a secondary cell group (SCG) of the terminal is in a suspended state, where the target process is used for requesting to recover at least one of the SCG and the MCG of the terminal.

Optionally, the target process is any one of a radio resource control (RRC) reestablishment process or an SCG recovery process.

Optionally, in a case that the target process is the SCG recovery process, the first execution module 501 includes:

- a first transmission unit, configured to transmit an SCG recovery request message to a first network node, where the SCG recovery request message includes at least one of first identification information, second identification information, or third identification information for indicating recovery of the SCG of the terminal; or a cause value for the terminal to perform the target process, where the cause value represents an MCG failure or MCG fast recovery; and
- the second identification information is obtained by a second network node by truncating the first identification information, and the third identification information is obtained by the terminal by truncating the first identification information.

Optionally, the first execution module 501 further includes:

- a first receiving unit, configured to receive a response message for the SCG recovery request message transmitted by the first network node, where
- the response message carries at least one of SCG configuration information or MCG configuration information.

Optionally, the cell group processing apparatus 500 further includes:

- a first transmission module, configured to:
- transmit a target message, where the target message is any one of:
- the target message is a first SCG recovery completion message in a case that the response message includes the MCG configuration information and the SCG configuration information, where the first SCG recovery completion message is used for indicating a success of SCG recovery of the terminal, and is further used for indicating a success or a failure of MCG recovery of the terminal;
- the target message is a second SCG recovery completion message in a case that the response message includes the SCG configuration information, where the second SCG recovery completion message is used for indicating a success of the SCG recovery of the terminal, and is further used for indicating a failure of the MCG recovery of the terminal; or the target message is an SCG recovery failure message in a case that the response message includes the MCG configuration information, where the SCG recovery failure message is used for indicating a failure of the SCG recovery of the terminal, and is further used for indicating a success or a failure of the MCG recovery.

Optionally, the first transmission module is configured to:

- transmit the target message to the first network node.

Optionally, the first transmission module is configured to perform any one of:

- transmitting, through the first network node, the target message to a master node (MN) corresponding to the terminal; or
- directly transmitting the target message to the MN corresponding to the terminal.

Optionally, the first network node is a network node of any one of:

- any cell group in a first cell list;
- a first cell group in the first cell list, where a primary secondary cell (PSCell) included in the first cell group satisfies a cell quality threshold;
- a second cell group in the first cell list, where a PSCell included in the second cell group is a PSCell having the best cell quality from candidate PSCells included in the first cell list; or
- a third cell group corresponding to a secondary node (SN) before the SCG of the terminal is suspended, where
- each of the cell groups includes at least a PSCell.

Optionally, before the execution of the target process in response to the master cell group (MCG) of the terminal failing in a case that the secondary cell group (SCG) of the terminal is in the suspended state, the cell group processing apparatus 500 further includes:

- a receiving module, configured to receive SCG suspension configuration information transmitted by a second network node.

Optionally, the SCG suspension configuration information includes at least one of:

- first identification information for indicating recovery of the SCG of the terminal;
- second identification information for indicating recovery of the SCG of the terminal, where the second identification information is obtained by truncating the first identification information;
- a first cell list for indicating recovery of the SCG of the terminal; or
- a cell quality threshold for indicating recovery of the SCG of the terminal.

Optionally, the first identification information includes at least one of:

- a cell-radio network temporary identifier (C-RNTI) used by the terminal in the master cell group (MCG);
- a C-RNTI used by the terminal in the SCG; or
- a resume ID of context information of the SCG of the terminal.

The cell group processing apparatus 500 provided in this embodiment of this application can realize all processes realized in the method embodiment of FIG. 2 and achieve the same technical effects. In order to avoid repetition, details are not described herein.

FIG. 6 is a structural diagram of a cell group processing apparatus according to an embodiment of this application. The cell group processing apparatus 600 shown in FIG. 6 may be applied to a terminal.

As shown in FIG. 6, the cell group processing apparatus 600 includes:

- a second execution module 601, configured to execute a target process in response to a master cell group (MCG) of a terminal failing in a case that a secondary cell group (SCG) of the terminal is in a suspended state, where the target process is used for recovering at least one of the SCG and the MCG of the terminal.

Optionally, the target process is any one of a radio resource control (RRC) reestablishment process or an SCG recovery process.

Optionally, in a case that the target process is the SCG recovery process, the second execution module 601 includes:

- a second receiving unit, configured to receive an SCG recovery request message transmitted by the terminal, where the SCG recovery request message includes at least one of first identification information, second identification information, or third identification information for indicating recovery of the SCG of the terminal; or a cause value for the terminal to perform the target process, where the cause value represents an MCG failure or MCG fast recovery; and
- the second identification information is obtained by a second network node by truncating the first identification information, and the third identification information is obtained by the terminal by truncating the first identification information.

Optionally, the second execution module 601 further includes:

- a second transmission unit, configured to transmit a response message for the SCG recovery request message to the terminal, where
- the response message carries at least one of SCG configuration information or MCG configuration information.

Optionally, the cell group processing apparatus 600 further includes:

- a second receiving module, configured to receive a target message transmitted by the terminal, where the target message is any one of:
- the target message is a first SCG recovery completion message in a case that the response message includes the MCG configuration information and the SCG configuration information, where the first SCG recovery completion message is used for indicating a success of SCG recovery of the terminal, and is further used for indicating a success or a failure of MCG recovery of the terminal;
- the target message is a second SCG recovery completion message in a case that the response message includes the SCG configuration information, where the second SCG recovery completion message is used for indicating a success of the SCG recovery of the terminal, and is further used for indicating a failure of the MCG recovery of the terminal; or
- the target message is an SCG recovery failure message in a case that the response message includes the MCG configuration information, where the SCG recovery failure message is used for indicating a failure of the SCG recovery of the terminal, and is further used for indicating a success or a failure of the MCG recovery.

Optionally, the cell group processing apparatus 600 further includes:

- a second transmission module, configured to transmit the target message to a master node (MN) corresponding to the terminal.

Optionally, the first receiving module is configured to perform any one of:

- receiving an SCG recovery completion message transmitted by the terminal in a case that the response message includes the MCG configuration information and the SCG configuration information; or
- receiving an SCG recovery completion message transmitted by the terminal in a case that the response message includes at least the SCG configuration information, where the SCG recovery completion message is further used for indicating a success or a failure of the MCG recovery.

Optionally, the first network node is a network node of any one of:

- any cell group in a first cell list;
- a first cell group in the first cell list, where a primary secondary cell (PSCell) included in the first cell group satisfies a cell quality threshold;
- a second cell group in the first cell list, where a PSCell included in the second cell group is a PSCell having the best cell quality from candidate PSCells included in the first cell list; or
- a third cell group corresponding to a secondary node (SN) before the SCG of the terminal is suspended, where
- each of the cell groups includes at least a PSCell.

The cell group processing apparatus 600 provided in this embodiment of this application can realize all processes realized in the method embodiment of FIG. 3 and achieve the same technical effects. In order to avoid repetition, details are not described herein.

FIG. 7 is a structural diagram of a cell group processing apparatus according to an embodiment of this application. The cell group processing apparatus 700 shown in FIG. 7 may be applied to a terminal.

As shown in FIG. 7, the cell group processing apparatus 700 includes:

- a third transmission module 701, configured to transmit SCG suspension configuration information to a terminal.

Optionally, the SCG suspension configuration information includes at least one of:

- first identification information for indicating recovery of the SCG of the terminal;
- second identification information for indicating recovery of the SCG of the terminal, where the second identification information is obtained by truncating the first identification information;
- a first cell list for indicating recovery of the SCG of the terminal; or
- a cell quality threshold for indicating recovery of the SCG of the terminal.

Optionally, the first identification information includes at least one of:

- a cell-radio network temporary identifier (C-RNTI) used by the terminal in the master cell group (MCG);
- a C-RNTI used by the terminal in the SCG; or
- a resume ID of context information of the SCG of the terminal.

The cell group processing apparatus 700 provided in this embodiment of this application can realize all processes realized in the method embodiment of FIG. 4 and achieve the same technical effects. In order to avoid repetition, details are not described herein.

Optionally, as shown in FIG. 8, an embodiment of this application further provides a communication device 800, including a processor 801, a memory 802, programs or instructions stored on memory 802 and executable on the processor 801. The programs or the instructions, when executed by the processor 801, implement the processes of the method embodiment of FIG. 2, the method embodiment of FIG. 3, or the method embodiment of FIG. 4, and can achieve the same technical effects. In order to avoid repetition, details are not described herein.

FIG. 9 is a second structural diagram of a communication device according to an embodiment of this application.

The communication device 900 includes but is not limited to a processor 901, a memory 902, a user interface 903, a transceiver 904, and a bus interface.

The structure of the communication device shown in FIG. 9 constitutes no limitation on the communication device, and the communication device may include more or fewer components than those shown in the figure, or some components may be combined, or a different component deployment may be used. Details are not described herein again.

In this embodiment of this application, the communication device 900 further includes programs or instructions stored on the memory 902 and executable on the processor 901.

I. The Communication Device 900 Acts as the Above Terminal.

When the programs or the instructions are executed by the processor 901, the following step is implemented:

- executing a target process in response to a master cell group (MCG) of the terminal failing in a case that a secondary cell group (SCG) of the terminal is in a suspended state, where the target process is used for requesting to recover at least one of the SCG and the MCG of the terminal.

Optionally, the target process is any one of a radio resource control (RRC) reestablishment process or an SCG recovery process.

Optionally, in a case that the target process is the SCG recovery process, the following step may be further implemented when the programs or the instructions are executed by the processor 901:

- transmitting an SCG recovery request message to a first network node through the transceiver 904, where the SCG recovery request message includes at least one of first identification information, second identification information, or third identification information for indicating recovery of the SCG of the terminal; or a cause value for the terminal to perform the target process, where the cause value represents an MCG failure or MCG fast recovery; and
- the second identification information is obtained by a second network node by truncating the first identification information, and the third identification information is obtained by the terminal by truncating the first identification information.

Optionally, the following step may be further implemented when the programs or instructions are executed by the processor 901:

- receiving, through the transceiver 904, a response message for the SCG recovery request message transmitted by the first network node, where
- the response message carries at least one of SCG configuration information or MCG configuration information.

Optionally, the following step may be further implemented when the programs or instructions are executed by the processor 901:

- transmit a target message through the transceiver 904, where the target message is any one of:
- the target message is a first SCG recovery completion message in a case that the response message includes the MCG configuration information and the SCG configuration information, where the first SCG recovery completion message is used for indicating a success of SCG recovery of the terminal, and is further used for indicating a success or a failure of MCG recovery of the terminal;
- the target message is a second SCG recovery completion message in a case that the response message includes the SCG configuration information, where the second SCG recovery completion message is used for indicating a success of the SCG recovery of the terminal, and is further used for indicating a failure of the MCG recovery of the terminal; or
- the target message is an SCG recovery failure message in a case that the response message includes the MCG configuration information, where the SCG recovery failure message is used for indicating a failure of the SCG recovery of the terminal, and is further used for indicating a success or a failure of the MCG recovery.

Optionally, the following step may be further implemented when the programs or instructions are executed by the processor 901:

- transmitting the target message to the first network node through the transceiver 904.

Optionally, any one of the following steps may be further implemented when the programs or instructions are executed by the processor 901:

- transmitting, through the transceiver 904 and the first network node, the target message to a master node (MN) corresponding to the terminal; or
- directly transmitting, through the transceiver 904, the target message to the MN corresponding to the terminal.

Optionally, the first network node is a network node of any one of:

- any cell group in a first cell list;
- a first cell group in the first cell list, where a primary secondary cell (PSCell) included in the first cell group satisfies a cell quality threshold;
- a second cell group in the first cell list, where a PSCell included in the second cell group is a PSCell having the best cell quality from candidate PSCells included in the first cell list; or
- a third cell group corresponding to a secondary node (SN) before the SCG of the terminal is suspended, where
- each of the cell groups includes at least a PSCell.

Optionally, the following step may be further implemented when the programs or instructions are executed by the processor 901:

- receiving, through the transceiver 904, SCG suspension configuration information transmitted by a second network node.

Optionally, the SCG suspension configuration information includes at least one of:

- first identification information for indicating recovery of the SCG of the terminal;
- second identification information for indicating recovery of the SCG of the terminal, where the second identification information is obtained by truncating the first identification information;
- a first cell list for indicating recovery of the SCG of the terminal; or
- a cell quality threshold for indicating recovery of the SCG of the terminal.

Optionally, the first identification information includes at least one of:

- a cell-radio network temporary identifier (C-RNTI) used by the terminal in the master cell group (MCG);
- a C-RNTI used by the terminal in the SCG; or
- a resume ID of context information of the SCG of the terminal.

It is to be noted that in this case, the above communication device 900 in this embodiment can achieve the processes in the method embodiment of FIG. 2 in the embodiments of this application, and can achieve the same beneficial effects. In order to avoid repetition, details are not described herein.

II. The Communication Device 900 Acts as the First Network Node.

When the programs or the instructions are executed by the processor 901, the following step is implemented:

executing a target process in response to a master cell group (MCG) of a terminal failing in a case that a secondary cell group (SCG) of the terminal is in a suspended state, where the target process is used for recovering at least one of the SCG and the MCG of the terminal.

Optionally, the target process is any one of a radio resource control (RRC) reestablishment process or an SCG recovery process.

Optionally, in a case that the target process is the SCG recovery process, the following step may be further implemented when the programs or the instructions are executed by the processor 901:

- receiving, through the transceiver 904, an SCG recovery request message transmitted by the terminal, where the SCG recovery request message includes at least one of first identification information, second identification information, or third identification information for indicating recovery of the SCG of the terminal; or a cause value for the terminal to perform the target process, where the cause value represents an MCG failure or MCG fast recovery; and
- the second identification information is obtained by a second network node by truncating the first identification information, and the third identification information is obtained by the terminal by truncating the first identification information.

Optionally, the following step may be further implemented when the programs or instructions are executed by the processor 901:

- transmitting a response message for the SCG recovery request message to the terminal through the transceiver 904, where
- the response message carries at least one of SCG configuration information or MCG configuration information.

Optionally, the following step may be further implemented when the programs or instructions are executed by the processor 901:

- receiving, through the transceiver 904, a target message transmitted by the terminal, where the target message is any one of:
- the target message is a first SCG recovery completion message in a case that the response message includes the MCG configuration information and the SCG configuration information, where the first SCG recovery completion message is used for indicating a success of SCG recovery of the terminal, and is further used for indicating a success or a failure of MCG recovery of the terminal;
- the target message is a second SCG recovery completion message in a case that the response message includes the SCG configuration information, where the second SCG recovery completion message is used for indicating a success of the SCG recovery of the terminal, and is further used for indicating a failure of the MCG recovery of the terminal; or
- the target message is an SCG recovery failure message in a case that the response message includes the MCG configuration information, where the SCG recovery failure message is used for indicating a failure of the SCG recovery of the terminal, and is further used for indicating a success or a failure of the MCG recovery.

Optionally, the following step may be further implemented when the programs or instructions are executed by the processor 901:

- transmitting, through the transceiver 904, the target message to a master node (MN) corresponding to the terminal.

Optionally, any one of the following steps may be further implemented when the programs or instructions are executed by the processor 901:

- receiving, through the transceiver 904, an SCG recovery completion message transmitted by the terminal in a case that the response message includes the MCG configuration information and the SCG configuration information; or
- receiving, through the transceiver 904, an SCG recovery completion message transmitted by the terminal in a case that the response message includes at least the SCG configuration information, where the SCG recovery completion message is further used for indicating a success or a failure of the MCG recovery.

Optionally, the first network node is a network node of any one of:

- any cell group in a first cell list;