CN110557783B

CN110557783B - Communication method and communication device in multi-system dual-connection

Info

Publication number: CN110557783B
Application number: CN201910899152.2A
Authority: CN
Inventors: 彭文杰; 李冠臣; 熊新; 戴明增
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-06-22
Filing date: 2018-11-02
Publication date: 2020-12-04
Anticipated expiration: 2038-11-02
Also published as: CN110557783A; WO2019242773A1

Abstract

In the method, when the length of the bearer PDCP SN changes, the SN sends a PDCP SN length change indication to the MN, so that the MN and the SN can generate bearer release and increased configuration information for a terminal, and the PDCP SN length change is completed.

Description

Communication method and communication device in multi-system dual-connection

Technical Field

The present application relates to the field of wireless communication technologies, and in particular, to a communication method and apparatus in multi-system dual connectivity.

Background

In order to increase the throughput of data transmission, dual connectivity is introduced supporting different access technologies. For example: multi-system Dual Connectivity (MR-DC).

Fig. 1 is a schematic diagram of a dual-connection communication system. As shown in fig. 1, the terminal 21 may simultaneously communicate with a Master Node (MN) 01 and a Secondary Node (SN) 11, MN01 and SN11 may be connected, and both the master node a and the secondary node B may be connected to a core network element 31. The access technologies employed by MN01 and SN11 may differ.

The MR-DC may specifically include the following scenarios:

1. evolved Universal Terrestrial Radio Access (E-UTRA) and New Radio Access (NR) Dual Connectivity (E-UTRA-NR Dual Connectivity, EN-DC)

As shown in fig. 2, the core network element 31 is an Evolved Packet Core (EPC), the MN01 is an evolved node b (eNB), and the SN11 is a new radio node b (gNB).

MN01 and SN11 can be connected through an X2 interface, and MN01 and SN11 can be connected through a user plane; the MN01 and the core network element 31 may be connected through an S1 interface, and the MN01 and the core network element 31 may have a user plane connection therebetween; the SN11 and the core network element 31 can be connected through an S1-U interface, and the SN11 core network element 31 can have a user plane connection.

2. Next Generation (NG) Radio Access Network (RAN) E-UTRA and NR Dual Connectivity (NG-RAN E-UTRA-NR Dual Connectivity, NGEN-DC)

As shown in fig. 3, the core network element 31 is a fifth Generation (5G, 5th Generation) core network (5G core, 5GC), the MN01 is an eNB, and the SN11 is a gNB.

MN01 and SN11 can be connected through Xn interface, MN01 and SN11 can have user interface connection; the MN01 and the core network element 31 can be connected through an NG interface, and the MN01 and the core network element 31 can be connected through a user plane; the SN11 and the core network element 31 can be connected through an NG-U interface, and the SN11 and the core network element 31 can have a user plane connection.

3. Double connection of NR and E-UTRA (NR-E-UTRA Dual Connectivity, NG-DC)

As shown in fig. 4, the core network element 31 is 5GC, MN01 is gNB, and SN11 is eNB.

MN01 and SN11 may be connected, for example, via an Xn interface, with a user plane connection between MN01 and SN 11; MN01 may be connected to the core network element 31, for example, through an NG interface, MN01 may have a user plane connection with the core network element 31; the SN11 and the core network element 31 may be connected, for example via a NG-U interface, and there may be a user plane connection between the SN11 and the core network element 31.

In each of the above scenarios, from the perspective of MN01 and SN11, the user plane may have the following 6 types of bearers, as shown in fig. 5, the following behavior examples respectively describe the data flow direction of each bearer type, and those skilled in the art can understand that the uplink is similar to the downlink and will not be described herein again.

1. MN terminated Master Cell Group (MCG) bearers.

Data is transmitted from the core network element 31 to the MN01, and is sequentially transmitted to the terminal 21 through a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, and a Media Access Control (MAC) layer of the MN 01.

2. MN terminated Secondary Cell Group (SCG) bearers.

The data is transmitted from the network element 31 of the core network to the MN01, transmitted to the RLC layer of the SN11 through the PDCP layer of the MN01, and transmitted to the terminal 21 through the RLC layer of the SN11 and the MAC layer in turn.

3. MN terminated Split (Split) bearers.

Data is sent from the network element 31 of the core network to the MN01, the PDCP layer of the MN101 shunts the data, a part of the data is sent to the terminal 21 through the RLC entity and the MAC entity of the MN01 in sequence, and the other part of the data is sent to the RLC layer of the SN11 and sent to the terminal 21 through the RLC layer and the MAC layer of the SN11 in sequence.

4. SN terminated Split bearers.

Data is sent from the network element 31 of the core network to the SN11, the PDCP layer of the SN11 shunts the data, a part of the data is sent to the terminal 21 through the RLC entity and the MAC entity of the SN11 in sequence, and the other part of the data is sent to the RLC layer of the MN101 and sent to the terminal 21 through the RLC layer and the MAC layer of the MN101 in sequence.

5. SN terminated MCG bearers.

The data is sent from the network element 31 of the core network to the SN11, sent to the RLC layer of MN01 via the PDCP layer of SN11, and sent to the terminal 21 via the RLC layer and the MAC layer of MN 01.

6. SN terminated SCG bearers.

The data is sent from the network element 31 of the core network to the SN11, and then sent to the terminal 21 through the PDCP layer, the RLC layer and the MAC layer of the SN 11.

The MCG bearer relates to an MCG air interface resource, the SCG bearer relates to an SCG air interface resource, and the Split bearer relates to an MCG air interface resource and an SCG air interface resource.

The PDCP entity of the bearer terminated at the MN is on the MN, and the PDCP entity of the bearer terminated at the SN is on the SN. Both the PDCP entity of the bearer terminated by the MN and the PDCP entity of the bearer terminated by the SN can be configured as NR PDCP entities. The NR PDCP entity may add a Sequence Number (SN) to each PDCP packet, so that the terminal 21 may sequence the plurality of PDCP packets according to the PDCP SNs after receiving the plurality of PDCP packets. There are many possibilities for the length of the PDCP SN, for example, 12 bits (bits) or 18 bits, and how to change the length of the PDCP SN for bearer is an urgent problem to be solved.

Disclosure of Invention

The embodiment of the application provides a communication method, a device and a system in multi-system dual connection, which can change the length of a loaded PDCP SN.

In a first aspect, an embodiment of the present application provides a communication method in multi-system dual connectivity. The method can be applied to the secondary node or a chip in the secondary node.

The method can comprise the following steps: generating a second PDCP SN length configuration for a first bearer, the second PDCP SN length configuration for the first bearer may indicate a second PDCP SN length for the first bearer; generating a PDCP SN length change indication of the first bearer when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer; sending the PDCP SN length change indication of the first bearer to the MN; wherein, the first PDCP SN length is the PDCP SN length of the first bearer before the second PDCP SN length.

The auxiliary node sends the PDCP SN length change indication to the main node, so that the main node can know the change of the PDCP SN length, and the auxiliary node and the main node can generate the loaded release and added configuration information for the terminal, thereby finishing the PDCP SN length change.

Optionally, in the method, when the length of the PDCP SN of the first bearer is the length of the first PDCP SN, the first bearer is terminated at a SN.

Optionally, in the method, the bearer type of the first bearer whose PDCP SN length is the first PDCP SN length is the same as the bearer type of the first bearer whose PDCP SN length is the second PDCP SN length.

Optionally, in the method, a bearer type of the first bearer where the PDCP SN length is the first PDCP SN length is different from a bearer type of the first bearer where the PDCP SN length is the second PDCP SN length.

Optionally, in the method, the sending, by the SN, the PDCP SN length change indication of the first bearer to the MN includes:

the SN sends an auxiliary node modification application message or an auxiliary node modification request response message to the MN, wherein the auxiliary node modification application message comprises the PDCP SN length change indication of the first bearer.

Optionally, the method further includes: the SN generates first configuration information of the first bearer; the SN sends the first configuration information of the first bearer to the MN. The first configuration information of the first bearer includes release and added configuration information of a PDCP entity.

Optionally, in the method, the first configuration information of the first bearer further includes configuration information of a release and an addition of an RLC entity.

Optionally, in the method, before the secondary node SN generates the second PDCP SN length configuration of the first bearer, the first bearer is terminated at an MN; the method further comprises the following steps: the SN receives a first PDCP SN length configuration from the MN, the first PDCP SN length configuration indicating the first PDCP SN length.

Optionally, in the method, the sending, by the SN, the PDCP SN length change indication of the first bearer to the MN includes: and sending an auxiliary node modification request message or an auxiliary node modification request response message to the MN, wherein the auxiliary node modification request message or the auxiliary node modification request response message comprises the PDCP SN length change indication of the first bearer.

Optionally, in the method, when the length of the PDCP SN of the first bearer is the length of the first PDCP SN, the first bearer is an MCG bearer terminated by an MN; the SN sending the PDCP SN length change indication of the first bearer to the MN, comprising: the SN sends a secondary node add request response message to the MN, the secondary node add request response message including the PDCP SN length change indication of the first bearer.

Optionally, the method further includes: the SN generates first configuration information of the first bearer; the SN sends the first configuration information of the first bearer to the MN; the first configuration information of the first bearer includes added configuration information of a PDCP entity.

Optionally, the method further includes: the SN generates first configuration information of the first bearer; the SN sends the first configuration information of the first bearer to the MN; the first configuration information of the first bearer includes deletion and addition configuration information of a PDCP entity.

In a second aspect, an embodiment of the present application provides a communication method in multi-system dual connectivity. The method can be applied to the secondary node or a chip in the secondary node.

The method comprises the following steps: receiving a second PDCP SN length of the second bearer from the MN; before receiving the second PDCP SN length of the second bearer from the MN, the PDCP length of the second bearer is the first PDCP SN length; determining that the PDCP SN length of the second bearer has changed when the second PDCP SN length of the second bearer is different from the first PDCP SN length of the second bearer.

The second PDCP SN length is sent to the SN through the MN, the SN can store the second PDCP SN length, the SN can autonomously judge whether the PDCP SN length changes, when the PDCP SN length can not only be 12 bits and 18 bits, the PDCP SN length change can have a plurality of possibilities, and the SN can judge whether the PDCP SN length changes, so that the SN can generate the release and the increased configuration information of the load for the terminal to finish the PDCP SN length change.

Optionally, in the method, when the length of the second bearer is the length of the first PDCP SN, the second bearer is terminated at the MN; and when the second bearer has the PDCP SN length equal to the second PDCP SN length, the second bearer is terminated at the MN.

Optionally, in the method, the bearer type of the second bearer whose PDCP SN length is the first PDCP SN length is the same as the bearer type of the second bearer whose PDCP SN length is the second PDCP SN length.

Optionally, in the method, a bearer type of the second bearer whose PDCP SN length is the first PDCP SN length is different from a bearer type of the second bearer whose PDCP SN length is the second PDCP SN length.

Optionally, the method further includes: generating first configuration information of the second bearer; the SN sends the first configuration information of the second bearer to the MN; the first configuration information of the second bearer includes configuration information of a release and addition of an RLC entity.

Optionally, in the method, when the length of the PDCP SN of the second bearer is the length of the first PDCP SN, the second bearer terminates at an SN; when the length of the second bearer is the length of the second PDCP SN, the second bearer is terminated at the MN; the method further comprises the following steps: the SN sends the first PDCP SN length to the MN.

Optionally, the method further includes: the SN generates first configuration information of the second bearer; the SN sends the first configuration information of the second bearer to the MN; the second configuration information of the second bearer includes configuration information of release of the PDCP entity.

Optionally, in the method, the first configuration information of the second bearer further includes configuration information of release and addition of an RLC entity.

Optionally, the method further includes: the SN generates first configuration information of the second bearer; the SN sends the first configuration information of the second bearer to the MN; the second configuration information of the second bearer includes configuration information of a release and addition of an RLC entity.

In a third aspect, an embodiment of the present application provides a communication method in multi-system dual connectivity, which may be applied to a master node or a chip in the master node.

The method comprises the following steps: receiving a PDCP SN length change indication of a first bearer from a SN; saving the PDCP SN length change indication for the first bearer.

The master node receives the PDCP SN length change indication from the auxiliary node, so that the master node can know the change of the PDCP SN length, the auxiliary node and the master node can generate the loaded release and added configuration information for the terminal, and the PDCP SN length change is completed.

Optionally, in the method, before the length of the PDCP SN of the first bearer changes, the first bearer terminates at a SN.

Optionally, in the method, the bearer type of the first bearer before the PDCP SN length change is the same as the bearer type of the first bearer after the PDCP SN length change.

Optionally, in the method, a bearer type of the first bearer before the PDCP SN length change is different from a bearer type of the first bearer after the PDCP SN length change.

Optionally, the method further includes: the MN receives SN configuration information of a first bearer from the SN; the MN sends the SN configuration information of the first bearer to the UE. Wherein the first configuration information of the first bearer includes configuration information of a release and an addition of a PDCP entity.

Optionally, the method further includes: generating second configuration information of the first bearer according to the PDCP SN length change indication of the first bearer; sending the second configuration information of the first bearer to a terminal; the second configuration information of the first bearer includes configuration information of a release and addition of an RLC entity.

Optionally, in the method, before the length of the PDCP SN of the first bearer changes, the first bearer is terminated at the MN;

the method further comprises the following steps: the MN sends the PDCP SN length of the first bearer before the PDCP SN length change to the SN.

Optionally, in the method, the first configuration information of the first bearer includes added configuration information of a PDCP entity.

Optionally, in the method, the first configuration information of the first bearer includes configuration information of release and addition of an RLC entity.

Optionally, the method further includes: generating second configuration information of the first bearer according to the PDCP SN length change indication of the first bearer; sending the second configuration information of the first bearer to a terminal; the second configuration information of the first bearer includes configuration information of release of the PDCP entity.

Optionally, the method further includes: the MN generates second configuration information of the first bearer according to the PDCP SN length change indication of the first bearer; MN sends the second configuration information of the first load to the terminal; the second configuration information of the first bearer includes configuration information of a release and an addition of the PDCP entity.

Optionally, in the method, the second configuration information of the first bearer further includes configuration information of release and addition of the RLC entity.

In a fourth aspect, an embodiment of the present application provides a communication method in multi-system dual connectivity, which may be applied to a master node or a chip in the master node.

The method comprises the following steps: generating a second PDCP SN length of a second bearer; before generating the second PDCP SN length of the second bearer, the PDCP SN length of the second bearer is the first PDCP SN length; determining that the PDCP SN length of the second bearer changes when the second PDCP SN length of the second bearer is different from the first PDCP SN length of the second bearer.

The MN can autonomously judge whether the PDCP SN length changes, when the PDCP SN length can not only be 12 bits or 18 bits, the PDCP SN length change has a plurality of possibilities, and the MN can judge whether the PDCP SN length changes, so that the MN can generate the configuration information of the release and the increase of the load for the terminal to complete the PDCP SN length change.

Optionally, in the method, when the length of the second bearer is equal to the length of the first PDCP SN, the second bearer is terminated at the MN.

Optionally, the method further includes: receiving first configuration information of the second bearer from the SN; the first configuration information of the second bearer includes configuration information of a release and addition of an RLC entity.

Optionally, the method further includes: generating second configuration information of the second bearer; the second configuration information of the second bearer includes release and added configuration information of a PDCP entity.

Optionally, in the method, the second configuration information of the second bearer further includes configuration information of a release and an addition of an RLC entity.

Optionally, in the method, when the length of the second bearer in PDCP SN is the length of the first PDCP SN, the second bearer is terminated in SN; the method further comprises the following steps: the first PDCP SN length is received from a SN. The SN may carry the first PDCP SN length in a cell that can be read by the MN, and the MN may read the first PDCP SN length, and optionally, the MN may store the first PDCP SN length. The first PDCP SN length is sent to the MN through the SN, the MN reads the first PDCP SN length, and the MN can autonomously judge whether the PDCP SN length changes.

Optionally, the method further includes: receiving first configuration information of the second bearer from the SN; the first configuration information of the second bearer includes configuration information of release of the PDCP entity.

Optionally, the method further includes: the first configuration information of the second bearer includes configuration information of a release and addition of an RLC entity.

Optionally, the method further includes: generating second configuration information of the second bearer; the second configuration information of the second bearer includes added configuration information of a PDCP entity.

Optionally, in the method, the second configuration information of the second bearer includes configuration information of a release and an addition of an RLC entity.

In a fifth aspect, an embodiment of the present application provides a communication apparatus, which may be applied to a secondary node or a chip in the secondary node. The communication device comprises a memory for storing a computer program and a processor for retrieving and running the computer program from the memory such that the method of the first or second aspect is described above.

In a sixth aspect, an embodiment of the present application provides a communication apparatus, which may be applied to a master node or a chip in the master node. The communication device comprises a memory for storing a computer program and a processor for retrieving and running the computer program from the memory such that the method of the third or fourth aspect is described above.

In a seventh aspect, an embodiment of the present application provides a computer storage medium storing a program for implementing the method of the first aspect or the second aspect. When the program is run in a wireless communication apparatus, the program causes the wireless communication apparatus to perform the method of the first aspect or the second aspect described above.

In an eighth aspect, an embodiment of the present application provides a computer storage medium storing a program for implementing the method of the first aspect or the second aspect. When the program is run in a wireless communication apparatus, the program causes the wireless communication apparatus to perform the method of the third or fourth aspect.

In a ninth aspect, the present application provides a computer program product, which includes a program that, when executed, causes the method of the first aspect or the second aspect to be performed.

In a tenth aspect, the present application provides a computer program product, which includes a program that, when executed, causes the method of the third or fourth aspect to be performed.

Drawings

In order to illustrate the present application more clearly, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be derived from these drawings by a person skilled in the art without inventive exercise.

FIG. 1 is a schematic diagram of a dual-connectivity communication system;

FIG. 2 is a schematic diagram of an EN-DC;

FIG. 3 is a schematic diagram of an NGEN-DC;

FIG. 4 is a schematic diagram of an NG-DC;

FIG. 5 is a schematic diagram of a user plane bearer type in MR-DC;

FIG. 6a is a diagram of a CU-DU structure with MN 01;

FIG. 6b is a diagram of an SN11 for CU-DU architecture;

FIG. 7 is a diagram of CU-DU architectures for both MN01 and SN 11;

FIG. 8 is a diagram illustrating an embodiment of changing the length of PDCP SNs;

FIG. 9 is a diagram illustrating an embodiment of changing the length of PDCP SNs;

FIG. 10 is a diagram illustrating another embodiment of changing the length of PDCP SNs;

FIG. 11 is a diagram illustrating another embodiment of changing the length of PDCP SNs;

FIG. 12a is a diagram illustrating another embodiment of changing the length of PDCP SNs;

FIG. 12b is a diagram of another embodiment for changing the length of PDCP SNs;

FIG. 13 is a diagram of another embodiment for changing the length of PDCP SNs;

FIG. 14 is a diagram illustrating an embodiment of changing the PDCP SN length under the CU-DU architecture;

fig. 15 is a schematic structural diagram of an access network device;

fig. 16 is a schematic structural diagram of a terminal;

FIG. 17 is a schematic diagram of an apparatus 1700;

FIG. 18 is a diagram illustrating another embodiment of changing the length of PDCP SNs;

FIG. 19 is a diagram illustrating another embodiment of changing the length of PDCP SNs;

FIG. 20 is a diagram illustrating another embodiment of changing the length of PDCP SNs.

Detailed Description

The technical solution in the present application will be described below with reference to the drawings in the present application.

The technical scheme of the embodiment of the application can be applied to the communication system shown in fig. 1. It should be noted that the core network element, the MN, the SN, and the terminal included in the communication system shown in fig. 1 are only an example, and the connection relationship between the core network element and the MN or the SN is also only an example, and in this embodiment of the present application, the type and the number of the network elements included in the communication system, and the connection relationship between the network elements are not limited thereto.

As shown in fig. 6a, when MN01 is a gNB, MN01 may be a Centralized Unit (CU) -Distributed Unit (DU) architecture, MN01 may include CU0111 and DU0121, e.g., in NG DC, MN01 is a gNB, MN01 may be a CU-DU architecture, and MN01 may include CU0111 and DU 0121. CU0111 and DU0121 are connected, for example, through an F1 interface, CU0111 is connected to a core network element 31, for example, through an NG interface, fig. 6a illustrates by taking 1 CU0111 and DU0121 as an example, in this embodiment, DU0121 may be multiple, the multiple DUs 0121 may share one CU0111, and the multiple DUs 0121 are all connected to CU0111, for example, through an F1 interface.

As shown in fig. 6b, when SN11 is a gNB, SN11 may be CU-DU architecture and SN11 may include CU1111 and DU1121, e.g., in EN-DC or NGEN-DC, SN11 is a gNB, SN11 may be CU-DU architecture and SN11 may include CU1111 and DU 1121. The CU1111 is connected to the DU1121, for example, through an F1 interface, and the CU1111 is connected to the core network element 31, for example, through an NG interface, and fig. 6b illustrates, by taking 1 CU1111 and a DU1121 as an example, in this embodiment of the present application, the DU1121 may be multiple, the multiple DUs 1121 may share one CU1111, and the multiple DUs 1121 are all connected to the CU1111, for example, through an F1 interface.

As shown in fig. 7, CU0111 and CU1111 may be connected when MN01 and SN11 are both CU-DU architectures.

Under the CU-DU architecture, part of functions of MN01 are deployed on CU0111, the other part of functions of MN01 are deployed on DU0121, and the functional division of CU0111 and DU0121 can be divided according to a wireless protocol stack. One possible method is to deploy a Radio Resource Control (RRC), a Service Data Adaptation (SDAP) layer, and a Packet Data Convergence Protocol (PDCP) layer in CU 0111; radio Link Control (RLC), Medium Access Control (MAC), and physical layer (PHY) are deployed in DU 0121. Another possible approach is to deploy RRC, PDCP, RLC, SDAP and MAC and partial physical layers in CU0111 and partial physical layers in DU 0121. It should be noted that the foregoing functional division is only an example, and other division manners are possible, which are not limited in this embodiment of the present application.

When the SN11 adopts the CU-DU architecture, the functions and functional division of the CU1111 and the DU1121 can refer to the related contents of the functions and functional division of the CU0111 and the DU0121 when the MN01 adopts the CU-DU architecture, which are not described herein again.

In the above communication system, MN01 (or SN11) can change the PDCP SN length when a bearer terminates at MN01 (or SN 11).

Embodiments of the present application provide a scheme in which a bearer performs release and addition when the length of the PDCP SN of the bearer changes. According to the scheme, when the length of the PDCP SN is changed, interaction is carried out between the MN01 and the SN11, so that both the MN01 and the SN11 can know that the length of the PDCP SN is changed, the MN01 and the terminal 21 can generate the release and added configuration information of the bearer for the terminal 21 at the same time, and the change of the length of the PDCP SN is completed.

The above schemes may specifically include a first scheme, a second scheme, and a third scheme. In a first scheme, SN11 may generate a new PDCP SN length for a bearer anchored by PDCP on SN11, when the new PDCP SN length changes from the previous PDCP SN length, SN11 sends a PDCP SN length change indication to MN01, and MN01 and SN11 generate release and added configuration information for the bearer for terminal 21. In the second scheme, the SN11 may send a PDCP SN length to the MN01, and the MN01 and the SN11 may save the PDCP SN length, and when the PDCP SN length changes, the MN01 and the SN11 generate configuration information of release and addition of a bearer for the terminal 21. In the third scheme, one PDCP SN length may be used in a fixed manner corresponding to one bearer type, and when the bearer type changes, MN01 and SN11 may know that the PDCP SN length has changed, so as to generate configuration information of release and addition of the bearer for terminal 21.

The words that may appear in the embodiments of the present application are explained below.

1. Generating the PDCP SN length of the first bearer may be understood as generating PDCP SN length configuration information of the first bearer, which may indicate the PDCP SN length of the first bearer. Transmitting or receiving the PDCP SN length of the first bearer may be understood as transmitting or receiving PDCP SN length configuration information of the first bearer, which may indicate the PDCP SN length of the first bearer.

2. The PDCP entity of the first bearer may be understood at the MN (or SN) as the PDCP anchor point of the first bearer at the MN (or SN); alternatively, the first bearer terminates at the MN (or SN); alternatively, a PDCP entity of the first bearer exists at the MN (or SN), or the first bearer exists at the MN (or SN).

The RLC entity (or MAC entity) having the first bearer on the MN (or SN) may be understood as the RLC entity (or MAC entity) having the first bearer on the MN (or SN).

3. The configuration information of the first bearer may include configuration information of one or more entities of a PDCP entity, an RLC entity, and a MAC entity of the first bearer. Different entities may have different names for operations of the entities, such as releasing or adding, and the embodiments of the present application do not limit this. For example, the addition of MAC entities can be understood as the addition of logical channels; or release of the MAC entity, may be understood as release of a logical channel or reset of the MAC entity.

First, the first embodiment will be explained below.

FIG. 8 is a diagram illustrating an embodiment of changing the length of PDCP SNs.

S801: the SN11 generates a second PDCP SN length for the first bearer. Which may be referred to herein as SN11, generates second PDCP SN length configuration information for the first bearer.

Since the node where the PDCP entity of the bearer is located can generate the PDCP SN, it can be understood by those skilled in the art that when the length of the PDCP SN of the first bearer is the second PDCP SN, the PDCP entity of the first bearer terminates at the SN11, i.e. the first bearer terminates at the SN.

S802: the SN generates a PDCP SN length change indication for the first bearer when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer.

The change in the PDCP SN length of the first bearer may indicate that the PDCP SN length of the first bearer has changed.

When the PDCP SN length of the first bearer is before the second PDCP SN length, the PDCP SN length of the first bearer may be the first PDCP SN length, which may be understood as before the SN11 generates or determines the second PDCP SN length of the first bearer, the PDCP SN length of the first bearer is the first PDCP SN length, or may be understood as before the PDCP SN length of the first bearer changes, the PDCP SN length of the first bearer is the first PDCP SN length, and after the PDCP SN length of the first bearer changes, the PDCP SN length of the first bearer is the second PDCP SN length.

In a first embodiment, when the PDCP SN length of the first bearer is the first PDCP SN length, the first bearer is terminated at an SN. That is, before the PDCP SN length of the first bearer changes, the PDCP entity of the first bearer may store, at SN11, the PDCP SN length of the first bearer and the PDCP related configuration of the first PDCP SN length, for example, the first PDCP SN length, SN11 may read the first PDCP SN length, compare with the second PDCP SN length, and generate the PDCP SN length change indication of the first bearer if the lengths are inconsistent.

In the first embodiment, the first bearer is terminated at the SN before and after the PDCP SN length of the first bearer is changed, i.e. the PDCP entities of the first bearer are all at the SN 11. Specifically, but not limited to, the following possibilities may be included: (1) the bearer types of the first bearer before and after the PDCP SN length change are the same, for example, the bearer types of the first bearer before the PDCP SN length change and after the PDCP SN length change are both an SN-terminated MCG bearer, an SN-terminated SCG bearer or an SN-terminated Split bearer; (2) the bearer type of the first bearer before and after the PDCP SN length change is different, for example, the bearer type of the first bearer before the PDCP SN length change is an SN-terminated MCG bearer, and the bearer type of the first bearer after the PDCP SN length change is an SN-terminated SCG bearer or an SN-terminated split bearer; or the bearer type of the first bearer before the change of the PDCP SN length is an SCG bearer terminated by the SN, and the bearer type of the first bearer after the change of the PDCP SN length is an MCG bearer terminated by the SN or a split bearer terminated by the SN; or the bearer type of the first bearer before the change of the PDCP SN length is a split bearer terminated by the SN, and the bearer type of the first bearer after the change of the PDCP SN length is an MCG bearer terminated by the SN or an SCG bearer terminated by the SN.

As a second implementation manner, when the PDCP SN length of the first bearer is the first PDCP SN length, the first bearer is terminated at the MN. That is, before the PDCP SN length of the first bearer changes, the PDCP entity of the first bearer is at MN01, MN01 may store PDCP SN length of the first bearer and PDCP related configuration of the first PDCP SN length, for example, the first PDCP SN length, MN01 may read the first PDCP SN length, MN01 then sends the first PDCP SN length to SN11, after receiving the first PDCP SN length, SN11 compares the first PDCP SN length with the second PDCP SN length, and if the first PDCP SN length does not match, generates a PDCP SN length change indication of the first bearer.

In a second embodiment, the first bearer terminates at the MN before the PDCP SN length change, and terminates at the SN after the PDCP SN length change. Specifically, but not limited to, the following possibilities may be included: for example, the bearer type of the first bearer before the PDCP SN length change is an MN-terminated MCG bearer, and the bearer type of the first bearer after the PDCP SN length change is an SN-terminated MCG bearer, an SN-terminated SCG bearer, or an SN-terminated split bearer; or the bearer type of the first bearer before the change of the PDCP SN length is an MN terminated SCG bearer, and the bearer type of the first bearer after the change of the PDCP SN length is an SN terminated MCG bearer, an SN terminated SCG bearer or an SN terminated split bearer; or the bearer type of the first bearer before the change of the PDCP SN length is a split bearer terminated by the MN, and the bearer type of the first bearer after the change of the PDCP SN length is an MCG bearer terminated by the SN, an SCG bearer terminated by the SN, or a split bearer terminated by the SN.

S803: the SN11 sends a PDCP SN length change indication of the first bearer to the MN 01.

In the first embodiment, the PDCP SN length change indication of the first bearer may be carried by a secondary node modification request (SN modification request) message or a secondary node modification request acknowledgement (SN modification request acknowledgement) message.

In the second embodiment, the PDCP SN length change indication of the first bearer may be carried by a secondary node add request acknowledgement message (SN add request acknowledge), a secondary node modify application message, or a modify request response message. For example, when the first bearer is an MCG bearer terminated by the MN before the PDCP SN length change, the request response message may be added by the secondary node or modified by the secondary node to carry the PDCPSN length change indication of the first bearer.

Optionally, the MN01 may save the PDCP SN length change indication sent by the SN 11.

Optionally, the MN01 may learn a new PDCP SN length according to the PDCP SN length change indication, for example, the second PDCP SN length, and the MN01 may store the second PDCP SN length, so that the MN01 may subsequently determine whether the PDCP SN length changes.

Optionally, S804-S806 may also be included.

S804: the SN11 generates first configuration information for the first bearer.

Optionally, S804 may be concurrent with S801, that is, when the SN11 generates the second PDCP SN length of the first bearer, the first configuration information of the first bearer may be generated.

As a first example of the first embodiment, the first configuration information includes configuration information of release and addition of the PDCP entity.

The first configuration information includes the configuration information of the release and the addition of the PDCP entity, and may be implemented by a cell including both the configuration information of the release and the addition of the PDCP entity, and specifically, may be implemented by deleting an identifier and adding a same identifier, which may be a bearer identifier, in a cell. For example, when the SN11 is a gNB, for example, in an EN-DC or NGEN-DC scenario, the first configuration information may be implemented by using a RadioBearerConfig cell in section 6.3.2 of 3GPP TS38.331V15.1.0, the first configuration information may include a RadioBearerConfig including configuration information for release of a PDCP entity, for example, DRB-ToReleaseList in the RadioBearerConfig includes bearer identity 1, and the RadioBearerConfig includes added configuration information of the PDCP entity, for example, DRB-ToAddMod in the RadioBearerConfig includes bearer identity 1. By deleting the bearer identifier which is the same as the added bearer identifier, the PDCP entity of one bearer can be deleted and then added in one configuration message, so that the change of the PDCP SN length is realized.

For example, the first configuration information includes the configuration information of the release and addition of the PDCP entity, and may include the possibility of the bearer type of the first bearer before and after the change of the PDCP SN length as enumerated in the first embodiment in S802.

As a second example of the first embodiment, on the basis of the first example of the first embodiment, the first configuration information may further include configuration information of release and addition of the RLC entity.

The first configuration information includes configuration information of the release and addition of the RLC entity, and may be implemented by including configuration information of the release and addition of the RLC entity in one cell, and specifically, may be implemented by deleting an identifier and adding an identical identifier in one cell, where the identifier may be a bearer identifier or a logical channel identifier. For example, when the SN11 is a gNB, e.g. in an EN-DC or NGEN-DC scenario, the first configuration information may be implemented with a CellGroupConfig cell in section 6.3.2 of 3GPP TS38.331V15.1.0, the CellGroupConfig comprising configuration information for release of the RLC entity, e.g. RLC-bearertorereleaselist in CellGroupConfig comprising logical channel identity 1, the CellGroupConfig comprising added configuration information for the RLC entity, e.g. RLC-bearertoladd modlist in CellGroupConfig comprising logical channel identity 1. For example, when the SN11 is an eNB, for example, in an NE-DC scenario, the first configuration information may be implemented by using a radioresourceconfigdetermined information element in section 6.3.2 of 3GPP TS36.331V15.1.0, where the first configuration information may include radioresourceconfigdetermined, a DRB-torelaselist in the radioresourceconfigdetermined includes bearer identity 1, and a DRB-ToAddMod includes bearer identity 1. By deleting the logical channel identifier or the bearer identifier which is the same as the added logical channel identifier or the bearer identifier, the RLC entity of one bearer can be deleted and then added in one configuration message, so that the change of the PDCP SN length is realized.

For example, the first configuration information including the configuration information of the release and addition of the RLC entity may include, but is not limited to, the following possibilities: the bearer type of the first bearer before the change of the PDCP SN length is an SN-terminated SCG bearer, and the bearer type of the first bearer after the change of the PDCP SN length is an SN-terminated SCG bearer or an SN-terminated split bearer; or the bearer type of the first bearer before the length change of the PDCP SN is a split bearer terminated by the SN, and the bearer type of the first bearer after the length change of the PDCP SN is an SCG bearer terminated by the SN or a split bearer terminated by the SN.

In the first embodiment, the first configuration information may be carried in an auxiliary node modification request response message or an auxiliary node modification application message.

As a first example of the second embodiment, the first configuration information includes added configuration information of the PDCP entity.

The first configuration information includes added configuration information of the PDCP entity, and may be implemented by including the added configuration information of the PDCP entity in one cell, for example, by adding an identifier, which may be a bearer identifier, in one cell. For example, the first configuration information may be implemented by using a radio bearer config cell in section 6.3.2 of 3GPP TS38.331V15.1.0, where the first configuration information may include a radio bearer config, the radio bearer config includes added configuration information of a PDCP entity, and for example, DRB-ToAddMod in the radio bearer config cell includes bearer identity 1.

It should be noted that, at this time, the first configuration information may not include the configuration information of the release of the PDCP entity, and since the PDCP entity of the first bearer is on the MN01 before the PDCP SN length is changed, the configuration information of the release of the PDCP entity may be generated for the terminal 21 by the MN 01.

For example, the first configuration information includes added configuration information of the PDCP entity, and may include the possibility of bearer types of the first bearer before and after the PDCP SN length change, which is enumerated in the second embodiment in S802.

As a second example of the second embodiment, the first configuration information includes configuration information of release and addition of the PDCP entity.

Reference may be made to the first configuration information in the first example of the first embodiment, which includes the relevant content in the configuration information of the release and the addition of the PDCP entity, and details are not repeated here.

It should be noted that, before the length of the PDCP SN is changed, the PDCP entity of the first bearer is located at MN01, after the length of the PDCP SN is changed, the PDCP entity of the first bearer is located at SN11, and the PDCP entity of MN01 and the PDCP entity of SN11 may both be configured with PDCP entities of the same standard, for example, NR PDCP entities, at this time, the release and added configuration information of the PDCP entity may be directly generated by SN11, at this time, MN01 does not need to generate configuration information of the release of the PDCP entity for terminal 21, and implementation complexity of the network and the terminal may be simplified.

As a third example in the second embodiment, on the basis of the first example in the second embodiment and the second example in the second embodiment, the first configuration information may further include configuration information of release and addition of the RLC entity.

Reference may be made to the relevant contents in the configuration information of the first configuration information including the release and addition of the RLC entity in the second example of the first embodiment, and details are not repeated here.

For example, the first configuration information includes configuration information of release and addition of the RLC entity, which may include, but is not limited to, the following possibilities: the bearer type of the first bearer before the change of the PDCP SN length is an MN terminated SCG bearer, and the bearer type of the first bearer after the change of the PDCP SN length is an SN terminated SCG bearer or an SN terminated split bearer; or the bearer type of the first bearer before the change of the PDCP SN length is a split bearer terminated by the MN, and the bearer type of the first bearer after the change of the PDCP SN length is an SCG bearer terminated by the SN or a split bearer terminated by the SN.

In a second implementation manner, the first configuration information may be carried in a request response message added by the secondary node and a request response message modified by the secondary node. For example, when the first bearer is an MCG bearer terminated by the MN before the PDCP SN length changes, the first configuration information may also be carried in a request response message added by the secondary node or a request response message modified by the secondary node.

S805: the SN11 sends first configuration information of the first bearer to the MN.

Optionally, S803 and S805 may be simultaneous, for example, the PDCP SN length change indication of the first bearer may be carried in the same message as the first configuration information of the first bearer and sent by the SN11 to the MN 01.

S806: MN01 sends first configuration information of the first bearer to terminal 21.

For example, MN01 may send an RRC connection reconfiguration message to terminal 21, the RRC connection reconfiguration message including first configuration information for the first bearer.

Optionally, S807-S808 may also be included.

S807: the MN01 generates second configuration information for the first bearer based on the PDCP SN length change indication for the first bearer.

As an example of the first embodiment, the second configuration information includes RLC release and addition configuration information.

The second configuration information includes the configuration information of the release and addition of the RLC entity, and may be implemented by a cell including the configuration information of the release and addition of the RLC entity at the same time, and specifically, may be implemented by deleting an identifier and adding a same identifier in a cell, where the identifier may be a bearer identifier or a logical channel identifier. For example, when MN01 is a gNB, e.g. in a NE-DC scenario, it may be implemented with a CellGroupConfig cell in section 6.3.2 of 3GPP TS38.331V15.1.0, the first configuration information may comprise a CellGroupConfig comprising configuration information for the release of the RLC entity, e.g. RLC-bearertorereleaselist in CellGroupConfig comprises logical channel identity 1, CellGroupConfig comprises added configuration information for the RLC entity, e.g. RLC-BearerToAddModList in CellGroupConfig comprises logical channel identity 1. For example, when the MN01 is an eNB, for example, in an EN-DC or NGEN-DC scenario, the second configuration information may be implemented by using a RadioResourceConfigDedicated cell in section 6.3.2 of 3GPP TS36.331V15.1.0, and the second configuration information may include RadioResourceConfigDedicated, where a DRB-ToReleaseList in the RadioResourceConfigDedicated includes a bearer identifier 1, and a DRB-ToAddMod includes a bearer identifier 1. By deleting the logical channel identifier or the bearer identifier which is the same as the added logical channel identifier or the bearer identifier, the RLC entity of one bearer can be deleted and then added in one configuration message, so that the change of the PDCP SN length is realized.

For example, the second configuration information includes configuration information of release and addition of the RLC entity, which may include, but is not limited to, the following possibilities: the bearer type of the first bearer before the change of the PDCP SN length is an SN-terminated MCG bearer, and the bearer type of the first bearer after the change of the PDCP SN length is an SN-terminated MCG bearer or an SN-terminated split bearer; the bearer type of the first bearer before the change of the PDCP SN length is a split bearer terminated by the SN, and the bearer type of the first bearer after the change of the PDCP SN length is an MCG bearer terminated by the SN or a split bearer terminated by the SN.

As a first example of the second embodiment, the second configuration information includes configuration information of release of the PDCP entity.

The second configuration information includes configuration information of release of the PDCP entity, and may be implemented by one cell including configuration information of release of the PDCP entity, and specifically, may be implemented by deleting an identifier, which may be a bearer identifier, in one cell. For example, the configuration may be implemented by using a radio bearer config cell in section 6.3.2 of 3GPP TS38.331V15.1.0, the second configuration information may include the radio bearer config, the radio bearer config includes configuration information for releasing the PDCP entity, for example, the DRB-ToReleaseList in the radio bearer config cell includes bearer identifier 1, and the processing that the RLC entity of one bearer is deleted before being added in one configuration message may be implemented, so as to implement the change of the PDCP SN length.

It should be noted that, since the PDCP entity of the first bearer is at MN01 before the length of the PDCP SN is changed, and after the length of the PDCP SN is changed, the PDCP entity of the first bearer may generate configuration information of release of the PDCP entity for the terminal 21 by MN01 and generate configuration information of addition of the PDCP entity for the terminal 21 by SN11 at SN 11. For example, under the possibility that the first bearer is of a bearer type before and after the change of the PDCP SN length as enumerated in the second embodiment in S802, the second configuration information may include configuration information of release of the PDCP entity,

as a second example of the second embodiment, on the basis of the first example of the second embodiment, the second configuration information may further include configuration information of release and addition of the RLC entity.

Reference may be made to the related content of the configuration information that the second configuration information includes RLC release and addition in S807 in an example of the first implementation, and details are not described herein again.

For example, the second configuration information may further include configuration information of release and addition of the RLC entity, in the following possibilities of bearer types before and after the PDCP SN length change: the bearer type of the first bearer before the change of the PDCP SN length is an MN-terminated MCG bearer, and the bearer type of the first bearer after the change of the PDCP SN length is an SN-terminated MCG bearer or an SN-terminated split bearer; or the bearer type of the first bearer before the change of the PDCP SN length is a split bearer terminated by the MN, and the bearer type of the first bearer after the change of the PDCP SN length is an MCG bearer terminated by the SN or a split bearer terminated by the SN.

As a third example of the second embodiment, the second configuration information includes configuration information of release and addition of the RLC entity.

It should be noted that, at this time, the second configuration information may not include the configuration information of the release of the PDCP entity, and the configuration information of the release of the PDCP entity may be generated by the SN11 for the terminal 21.

For example, the second configuration information may include configuration information of release and addition of the RLC entity, in the following possibilities of bearer types before and after the PDCP SN length change: the bearer type of the first bearer before the change of the PDCP SN length is an MN-terminated MCG bearer, and the bearer type of the first bearer after the change of the PDCP SN length is an SN-terminated MCG bearer or an SN-terminated split bearer; or the bearer type of the first bearer before the change of the PDCP SN length is a split bearer terminated by the MN, and the bearer type of the first bearer after the change of the PDCP SN length is an MCG bearer terminated by the SN or a split bearer terminated by the SN.

S808: MN01 sends the second configuration information of the first bearer to terminal 21.

For example, MN01 may send an RRC connection reconfiguration message to terminal 21, the RRC connection reconfiguration message including the second configuration information of the first bearer.

Optionally, S806 and S808 may occur simultaneously, for example, the MN01 sends a message to the terminal 21, where the message carries the first configuration information and the second configuration information of the first bearer simultaneously, and the message may be an RRC connection reconfiguration message.

The change of the PDCP SN length is further described with reference to fig. 9 to 12 a.

How to change the PDCP SN length in the SN increase request procedure will be described below in conjunction with the SN increase request procedure.

FIG. 9 is a diagram illustrating an embodiment of changing the length of PDCP SNs.

S901: MN01 sends a secondary node addition request message to SN 11.

Before the MN01 sends the secondary node addition request message to the SN11, the bearer type of the first bearer may be an MCG bearer terminated by the MN, the MN01 may determine the bearer type of the first bearer after the secondary node is added, and the first bearer may be terminated at the SN after the secondary node is added, that is, the PDCP entity of the first bearer after the secondary node is added is on the SN11, for example, the bearer type of the first bearer after the secondary node is an MCG bearer terminated by the SN, an SCG bearer terminated by the SN, or a split bearer terminated by the SN.

The secondary node addition request message may include:

(1) a bearer identity of the first bearer.

(2) And adding the indication information of the bearer type of the first bearer after the auxiliary node is added.

For example, the method may include whether the PDCP entity of the first bearer is on the SN11 after the secondary node is added, whether the first bearer has MCG resources after the secondary node is added, and whether the first bearer has SCG resources after the secondary node is added.

For example, after the auxiliary node is added, the PDCP entity of the first bearer is located in SN11, after the auxiliary node is added, the first bearer has an MCG resource, and there is no SCG resource, that is, after the auxiliary node is added, the bearer type of the first bearer is an MCG bearer terminated by SN; or, after the auxiliary node is added, the PDCP entity of the first bearer is in SN11, after the auxiliary node is added, the first bearer does not have an MCG resource, and has an SCG resource, that is, after the auxiliary node is added, the bearer type of the first bearer is an SCG bearer terminated by SN; or, after the auxiliary node is added, the PDCP entity of the first bearer is located in SN11, and after the auxiliary node is added, the first bearer has MCG resources and SCG resources, that is, the bearer type of the first bearer after the auxiliary node is added is a split bearer terminated by SN.

(3) The configuration information of the PDCP entity of the first bearer at MN01 includes the PDCP SN length of the first bearer at MN01, i.e. the first PDCP SN length in fig. 8, for example, the first PDCP SN length may be 12 bits. The configuration information of the PDCP entity of the first bearer at MN01 may be used to assist SN11 in generating configuration information of a new PDCP entity.

S902 to S907 are further described below as an example of S801 to S808.

S902: the SN11 generates a second PDCP SN length for the first bearer.

Before S902, since the PDCP entity of the first bearer is on the SN11 after the secondary node is added, the SN11 may decide to generate a PDCP SN length, i.e. the second PDCP SN length in S801 in fig. 8, for example, the second PDCP SN length is 18 bit.

S903: the SN11 generates a PDCP SN length change indication for the first bearer when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer.

When the PDCP SN length of the first bearer is before the second PDCP SN length, the PDCP SN length of the first bearer may be the first PDCP SN length, which may be understood as before the SN11 generates the second PDCP SN length of the first bearer, the PDCP SN length of the first bearer is the first PDCP SN length, or may be understood as before the PDCP SN length of the first bearer changes, the PDCP SN length of the first bearer is the first PDCP SN length, and after the PDCP SN length of the first bearer changes, the PDCP SN length of the first bearer is the second PDCP SN length.

For example, the length of the first PDCP SN of the first bearer is 12 bits, the length of the second PDCP SN of the first bearer is 18 bits, the lengths of the first and second PDCP SNs are different, and the SN11 generates a PDCP SN length change indication of the first bearer.

S904: the SN11 generates first configuration information for the first bearer.

Optionally, S902 may be concurrent with S904, that is, when the SN11 generates the first configuration information of the first bearer, the second PDCP SN length of the first bearer may be generated.

The first configuration information of the first bearer may be configuration information of an entity of the first bearer on the SN11 generated by the SN11 for the terminal 21.

Because no entity of the first bearer is on the SN11 before the auxiliary node is added, for example, the bearer type of the first bearer before the auxiliary node is added is an MCG bearer terminated by the MN, the PDCP entity, the RLC entity, and the MAC entity of the first bearer are all on the MN 01; after the secondary node is added, the PDCP entity of the first bearer is at SN11, the RLC entity or MAC entity may or may not be at SN11, and the RLC entity or MAC entity may or may not be at MN01, for example, after the secondary node is added, the bearer type of the first bearer is an MCG bearer terminated by SN, the PDCP entity of the first bearer is at SN11, and the RLC entity and MAC entity of the first bearer are at MN 01; after the auxiliary node is added, the bearing type of the first bearing is SCG bearing terminated by SN, and a PDCP entity, an RLC entity and an MAC entity of the first bearing are positioned on SN 11; after the secondary node is added, the bearer type of the first bearer is a split bearer terminated by the SN, the PDCP entity of the first bearer is on the SN11, and the RLC entity and the MAC entity of the first bearer are on the MN01 and the SN 11.

If the previous entity (e.g., PDCP entity, RLC entity, or MAC entity) before adding the secondary node is not at SN11, and the entity is at SN11 after adding the secondary node, the first configuration information on the first bearer may include the added configuration information of the entity.

The first configuration information of the first bearer may include configuration information of the PDCP entity, e.g., added configuration information of the PDCP entity; or, for example, the first configuration information may include the released and added configuration information of the PDCP entity, for example, the PDCP of MN01 and SN11 may both be NR PDCP, MN01 may generate the released configuration information of the PDCP entity for terminal 21, or SN11 may directly generate the released configuration information of the PDCP entity at the same time of generating the added configuration information of the PDCP entity, and at this time, MN01 is not required to regenerate the released configuration information of the PDCP entity.

Optionally, the first configuration information of the first bearer may further include configuration information of an RLC entity and configuration information of a MAC entity, for example, incremental configuration information of the RLC entity and incremental configuration information of the MAC entity.

For example, the bearer type of the first bearer before the auxiliary node is added is an MCG bearer terminated by MN, the bearer type of the first bearer after the auxiliary node is added is an MCG bearer terminated by SN, and the first configuration information of the first bearer may include added configuration information of the PDCP entity or release and added configuration information of the PDCP entity.

For example, the bearer type of the first bearer before the secondary node is added is an MN-terminated MCG bearer, the bearer type of the first bearer after the secondary node is added is an SN-terminated SCG bearer or an SN-terminated split bearer, and the first configuration information of the first bearer may include added configuration information of a PDCP entity or release and added configuration information of the PDCP entity, and added configuration information of an RLC entity and added configuration information of an MAC entity.

In the embodiment of the present application, for example, the configuration information of the PDCP entity on MN01 or SN01 may be implemented by a RadioBearerConfig cell in section 6.3.2 of 3 GPPTS38.331V15.1.0; the configuration information of the RLC entity and the MAC entity of MN01 or SN01 may be implemented by a CellGroupConfig cell in section 6.3.2 of 3GPP TS38.331V15.1.0 or a RadioResourceConfigDedicated cell in section 6.3.2 of 3GPP TS36.331V15.1.0.

S905: SN11 sends a secondary node addition request response message to MN 01.

The secondary node addition request response message may include a bearer identification of the first bearer, a PDCP SN length change indication of the first bearer, and first configuration information of the first bearer.

Optionally, a new cell may be defined in the auxiliary node add request response message, and the PDCP SN length change indication of the first bearer may be carried in the new cell. The PDCP SN length change indication may be carried by 1bit, e.g., 1 represents a PDCP SN length change and 0 represents no change in PDCP SN length.

S906: the MN01 generates second configuration information for the first bearer based on the PDCP SN length change indication for the first bearer.

The second configuration information of the first bearer may be configuration information of an entity of the first bearer on MN01 generated by MN01 for the terminal 21.

If a previous entity (e.g., PDCP entity, RLC entity, or MAC entity) of the secondary node is added to the MN01, and the previous entity of the secondary node is added to the MN01, the first configuration information on the first bearer may include the release and addition configuration information of the previous entity of the secondary node; if a previous entity (e.g., PDCP entity, RLC entity, or MAC entity) of the secondary node is added on MN01, and the previous entity is not on MN01 after the secondary node is added, the first configuration information on the first bearer may include the released configuration information of the previous entity.

The second configuration information of the first bearer may include configuration information of the PDCP entity, e.g., configuration information of a release of the PDCP entity. At this time, the released configuration information of the PDCP entity is generated for the terminal 21 by the MN 01. Alternatively, the second configuration information of the first bearer may not include the configuration information of the release of the PDCP entity, which is generated by the SN11 for the terminal 21.

Optionally, the second configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, configuration information of release and addition of the RLC entity and configuration information of release and addition of the MAC entity.

For example, the bearer type of the first bearer before the secondary node is added is an MCG bearer terminated by MN, and the bearer type of the first bearer after the secondary node is added is an SN-terminated MCG or an SN-terminated split bearer.

Optionally, the second configuration information of the first bearer may further include configuration information of a release of the RLC entity and configuration information of a release of the MAC entity.

For example, the bearer type of the first bearer before the auxiliary node is added is an MCG bearer terminated by MN, and the bearer type of the first bearer after the auxiliary node is added is an SCG bearer terminated by SN.

S907: MN01 sends an RRC connection reconfiguration message to terminal 21.

The RRC connection reconfiguration message may include an identifier of the first bearer, first configuration information of the first bearer, and second configuration information of the first bearer.

S908: the terminal 21 sends an RRC connection reconfiguration complete message to the MN 01.

The terminal 21 performs the operation of deleting the bearer first and then adding the bearer according to the bearer identifier, the first configuration information of the first bearer, and the second configuration information of the first bearer included in the RRC connection reconfiguration message.

S909: MN01 sends a SN reconfiguration complete message to SN 11.

S910: the terminal 21 completes random access with the SN 11.

How to change the length of the PDCP SN in the secondary node modification procedure is described below in conjunction with the secondary node triggering the secondary node modification procedure.

After the secondary node addition is completed, for example, referring to the relevant content in fig. 9, the PDCP entity of the first bearer may be on the SN11, for example, the bearer type of the first bearer is an SN-terminated MCG bearer, an SN-terminated SCG bearer, or an SN-terminated split bearer. The SN11 may maintain PDCP configuration, e.g., through the secondary node modification procedure, the SN11 may modify the PDCP SN length without changing the bearer type, the SN 11.

FIG. 10 is a diagram of another embodiment for changing the length of PDCP SNs.

S1001: the SN11 generates a second PDCP SN length for the first bearer.

For example, the second PDCP SN may be 12 bits long.

For example, the first bearer is an SN-terminated MCG bearer, an SN-terminated SCG bearer, or an SN-terminated split bearer.

S1002: the SN11 generates first configuration information for the first bearer.

Optionally, S1002 may be concurrent with S1001, that is, when the SN11 generates the first configuration information of the first bearer, the second PDCP SN length of the first bearer may be generated.

Before and after changing the length of the PDCP SN, the bearer type of the first bearer is not changed, the PDCP entity of the first bearer is at SN11, the RLC entity and the MAC entity may or may not be at SN11, for example, the first bearer is an MCG bearer terminated by SN, the PDCP entity of the first bearer is at SN11, and the RLC entity and the MAC entity are not at SN 11; the first bearer is an SN-terminated SCG bearer or an SN-terminated split bearer, the PDCP entity of the first bearer is at SN11, and the RLC entity and the MAC entity are at SN 11.

For example, if a previous entity (e.g., PDCP entity, RLC entity, or MAC entity) of the secondary node is added at SN11, and the previous entity of the secondary node is added at SN11, the first configuration information on the first bearer may include the release and added configuration information of the previous entity of the secondary node.

The first configuration information of the first bearer may include configuration information of the PDCP entity, e.g., release and add configuration information of the PDCP entity.

Optionally, the first configuration information of the first bearer may further include configuration information of the RLC entity and the MAC entity, for example, configuration information of release and addition of the RLC entity and the MAC entity.

For example, the first bearer is an SN-terminated MCG bearer, and the first configuration information of the first bearer may include configuration information of release and addition of the PDCP entity.

For example, the first bearer is an SN-terminated SCG bearer or an SN-terminated split bearer, and the first configuration information of the first bearer may include configuration information of release and addition of the PDCP entity and configuration information of release and addition of the RLC entity and the MAC entity.

S1003: the SN11 generates a PDCP SN length change indication for the first bearer when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer.

The first bearer terminates at SN11 before changing the PDCP SN length, and the SN11 may obtain the first PDCP SN length, which may be 18 bits, for example.

For example, the first PDCP SN length may be 18 bits, the second PDCP SN length may be 12 bits, the first PDCP SN length and the second PDCP SN length are different, and the SN11 generates a PDCP SN length change indication for the first bearer.

S1004: SN11 sends a secondary node modification application message to MN 01.

The secondary node modification application message may include a bearer identification of the first bearer, a PDCP SN length change indication of the first bearer, and first configuration information of the first bearer.

Optionally, a new cell may be defined in the secondary node modification application message, and the PDCP SN length change indication of the first bearer may be carried in the new cell. The PDCP SN length change indication may be carried by 1bit, e.g., 1 represents a PDCP SN length change and 0 represents no change in PDCP SN length.

S1005: the MN01 generates second configuration information for the first bearer based on the PDCP SN length change indication for the first bearer.

For example, if a previous entity (e.g., RLC entity or MAC entity) of the secondary node is added on MN01 and the previous entity of the secondary node is added on MN01, the first configuration information on the first bearer may include the release and added configuration information of the previous entity of the secondary node.

The second configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, configuration information of release and addition of the RLC entity and configuration information of release and addition of the MAC entity.

For example, the first bearer is an SN-terminated MCG bearer or an SN-terminated split bearer, and the second configuration information of the first bearer may include configuration information of release and addition of the RLC entity and the MAC entity.

For example, when the first bearer is an SCG bearer terminated by an SN, the first bearer is not physically located on MN01, and the second configuration information of the first bearer may not be generated.

S1006: MN01 sends an RRC connection reconfiguration message to terminal 21.

S1007: the terminal 21 sends an RRC connection reconfiguration complete message to the MN 01.

S1008: MN01 sends a secondary node modification acknowledgement message to SN 11.

How to change the PDCP SN length in the secondary node modification procedure is described below in conjunction with the secondary node modification procedure.

After the secondary node addition or the secondary node triggered modification by the secondary node is completed, for example, referring to relevant contents in fig. 9 and fig. 10, the PDCP entity of the first bearer may be on the SN11, for example, the bearer type of the first bearer is an SN-terminated MCG bearer, an SN-terminated SCG bearer, or an SN-terminated split bearer. Optionally, the MN01 may modify the procedure by initiating the secondary node, or the SN11 may change the bearer type of the first bearer by requesting the MN01 to initiate the secondary node modification procedure, for example, the type of the first bearer, an MN-terminated MCG bearer, an MN-terminated SCG bearer, or an MN-terminated split bearer. The PDCP SN length can be modified by the SN11 with or without changing the bearer type under the above six bearer types of the first bearer by the MN01 initiating the secondary node modification procedure, or the SN11 can initiate the secondary node modification procedure by requesting MN 01.

FIG. 11 is a diagram of another embodiment for changing the length of PDCP SNs.

S1101: MN01 sends a secondary node modification request message to SN 11.

Before the MN01 sends the secondary node modification request message to the SN11, the bearer type of the first bearer may be a MN-terminated MCG bearer, a MN-terminated SCG bearer, a MN-terminated split bearer, a SN-terminated MCG bearer, a SN-terminated SCG bearer, or a SN-terminated split bearer.

MN01 may modify the bearer type of the first bearer through the secondary node modification request message, for example, may modify the bearer type of the first bearer to be a SN-terminated bearer type, for example, the above three MN-terminated bearer types may be modified to be any one SN-terminated bearer type, and the above one SN-terminated bearer type may be modified to be two other SN-terminated bearer types.

The secondary node modification request message may include:

(1) a bearer identity of the first bearer.

(2) Modified bearer type indication information.

The modified bearer type may be a SN terminated bearer type.

For example, the method may include whether the PDCP entity of the first bearer after bearer type modification is on the SN11, whether the first bearer has MCG resources after adding the secondary node, and whether the first bearer has SCG resources after adding the secondary node.

(3) Optionally, before changing the bearer type of the first bearer, the first bearer terminates at MN01, which may include configuration information of the PDCP entity of the first bearer at MN01, and may include a PDCP SN length of the first bearer at MN01, that is, the first PDCP SN length in fig. 8, for example, the first PDCP SN length may be 12 bits. The configuration information of the PDCP entity of the first bearer at MN01 may be used to assist SN11 in generating configuration information of a new PDCP entity.

Optionally, before S1101, S1100 may be further included.

S1100: SN11 sends a secondary node modification application message to MN 01.

MN01 may be requested by SN11 to initiate a secondary node modification procedure.

S1102: the SN11 generates a second PDCP SN length for the first bearer.

Since the first bearer may be terminated with SN after the bearer type of the first bearer is modified, the SN11 may generate a second PDCP SN length of the first bearer, that is, the second PDCP SN length in S801 in fig. 8, for example, the second PDCP SN length is 18 bits.

S1103: the SN11 generates a PDCP SN length change indication for the first bearer when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer.

Wherein, before the PDCP SN length of the first bearer is the second PDCP SN length, the PDCP SN length of the first bearer can be the first PDCP SN length.

S1104: the SN11 generates first configuration information for the first bearer.

Optionally, S1103 may be concurrent with S1102, that is, when the SN11 generates the first configuration information of the first bearer, the second PDCP SN length of the first bearer may be generated.

The first bearer may be terminated at the SN before the bearer type is changed, the PDCP entity of the first bearer may be at the SN11, the RLC entity and MAC entity may or may not be at the SN11, and the RLC entity or MAC entity may or may not be at MN01 before the bearer type is changed. For example, the first bearer is an SN-terminated MCG bearer before changing bearer type, the PDCP entity is at SN11, and the RLC entity and MAC entity are at MN 01; for example, the first bearer is an SN-terminated SCG bearer before changing the bearer type, and the PDCP entity, the RLC entity, and the MAC entity are at SN 11; for example, the first bearer is a SN terminated split bearer before changing bearer type, PDCP entity is on SN11, RLC entity and MAC entity are on MN01 and SN 01. The first bearer may terminate at the SN after the bearer type is changed, and its entity at the SN11 may refer to the associated description of the entity of the first bearer at the SN11 before the bearer type is changed.

The first bearer may be terminated at the MN before the bearer type is changed, the PDCP entity of the first bearer may be at MN01 before the bearer type is changed, the RLC entity and the MAC entity may or may not be at MN01, and the RLC entity or the MAC entity may or may not be at SN 11. For example, the first bearer is an MN-terminated MCG bearer before changing bearer type, the PDCP entity is on MN01, and the RLC entity and MAC entity are on MN 01; for example, the first bearer is an MN-terminated SCG bearer before changing bearer types, the PDCP entity may be on MN01, and the RLC entity and MAC entity are on SN 11; for example, the first bearer is a split bearer terminated by MN before changing bearer type, PDCP entity is on MN01, RLC entity and MAC entity are on MN01 and SN 01. The first bearer may terminate at the SN after the bearer type is changed, and its entity at the SN11 may refer to the associated description of the entity of the first bearer at the SN11 before the bearer type is changed.

If an entity (e.g., PDCP entity, RLC entity, or MAC entity) is not in SN11 before changing the bearer type and the entity is in SN11 after changing the bearer type, the first configuration information on the first bearer may include incremental configuration information of the entity; if an entity (e.g., PDCP entity, RLC entity, or MAC entity) before changing the bearer type is on SN11 and the entity after changing the bearer type is on SN11, the first configuration information on the first bearer may include the configuration information of the release and addition of the entity; if an entity (e.g., a PDCP entity, an RLC entity, or a MAC entity) is on the SN11 before changing the bearer type and the entity is not on the SN11 after changing the bearer type, the first configuration information on the first bearer may include the released configuration information of the entity.

Before changing the bearer type, the first bearer is terminated at the SN, that is, the first bearer is modified from one of an SN-terminated MCG bearer, an SN-terminated SCG bearer or an SN-terminated split bearer to another one of the SN-terminated MCG bearer, the SN-terminated SCG bearer or the SN-terminated split bearer, and the first configuration information of the first bearer may include the following:

as a first example, the first configuration information of the first bearer may include configuration information of the PDCP entity, such as release and addition configuration information of the PDCP entity.

As a second example, on the basis of the first example, the first configuration information of the first bearer may further include configuration information of the RLC entity and the MAC entity, for example, configuration information of release and addition of the RLC entity and the MAC entity.

As a third example, on the basis of the first example, the first configuration information of the first bearer may further include configuration information of the RLC entity and the MAC entity, for example, configuration information of release of the RLC entity and the MAC entity.

As a fourth example, on the basis of the first example, the first configuration information of the first bearer may further include configuration information of the RLC entity and the MAC entity, for example, added configuration information of the RLC entity and the MAC entity.

For example, the bearer type of the first bearer is an SCG bearer terminated by an SN before the bearer type is modified, and the bearer type of the first bearer is a split bearer terminated by an SN after the bearer type is modified; or, before modifying the bearer type, the bearer type of the first bearer is a split bearer terminated by SN, and after modifying the bearer type, the bearer type of the first bearer is an SCG bearer terminated by SN, and the first configuration information of the first bearer may include configuration information of release and addition of a PDCP entity and configuration information of release and addition of an RLC entity and an MAC entity.

For example, the bearer type of the first bearer is an SCG bearer or a split bearer terminated by SN before the bearer type is modified, the bearer type of the first bearer is an MCG bearer terminated by SN after the bearer type is modified, and the first configuration information of the first bearer may include configuration information of release and addition of a PDCP entity and configuration information of release of an RLC entity and a MAC entity.

For example, the bearer type of the first bearer is an SN-terminated MCG bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated split bearer or an SN-terminated SCG bearer after the bearer type is modified, and the first configuration information of the first bearer may include release and added configuration information of the PDCP entity and added configuration information of the RLC entity and the MAC entity.

Before changing the bearer type, the first bearer is terminated at the MN, that is, the first bearer is modified from one of an MCG bearer terminated by the MN, an SN-terminated SCG bearer, or an SN-terminated split bearer to one of an SN-terminated MCG bearer, an SN-terminated SCG bearer, or an SN-terminated split bearer, and the first configuration information of the first bearer may include the following:

as a first example, the first configuration information of the first bearer may include configuration information of a PDCP entity, e.g., added configuration information of the PDCP entity, or may include release and added configuration information of the PDCP entity, e.g., the first configuration information of the first bearer. For example, the PDCP of MN01 and SN11 may be NR PDCP, MN01 may generate release information of the PDCP entity for the terminal 21, or SN11 may generate the release configuration information of the PDCP entity while generating the added configuration information of the PDCP entity, and at this time, MN01 is not required to regenerate the release configuration information of the PDCP entity.

As a second example, on the basis of the first example, the first configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, configuration information of release and addition of the RLC entity and the MAC entity.

As a third example, on the basis of the first example, the first configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, configuration information of release of the RLC entity and the MAC entity.

As a fourth example, based on the first example, the first configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, added configuration information of the RLC entity and the MAC entity.

For example, the bearer type of the first bearer is an MN-terminated MCG bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated MCG bearer after the bearer type is modified, and the first configuration information of the first bearer may include configuration information of a PDCP entity or configuration information of release and addition of PDCP.

For example, the bearer type of the first bearer is an MN-terminated SCG bearer or an MN-terminated split bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated SCG bearer or an SN-terminated split bearer after the bearer type is modified, and the first configuration information of the first bearer may include configuration information of a PDCP entity or configuration information of release and addition of PDCP, and configuration information of release and addition of an RLC entity and an MAC entity.

For example, the bearer type of the first bearer is an MN-terminated MCG bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated SCG bearer or a split bearer after the bearer type is modified, and the first configuration information of the first bearer may include configuration information of a PDCP entity or configuration information of release and addition of PDCP, and configuration information of addition of an RLC entity and an MAC entity.

For example, the bearer type of the first bearer is an MN-terminated SCG bearer or an MN-terminated split bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated MCG bearer after the bearer type is modified, and the first configuration information of the first bearer may include configuration information of a PDCP entity or configuration information of release and addition of PDCP, and configuration information of release of an RLC entity and an MAC entity.

S1105: SN11 sends a secondary node modification request response message to MN 01.

The secondary node modification request response message may include a bearer identification of the first bearer, a PDCP SN length change indication of the first bearer, and first configuration information of the first bearer.

Optionally, a new cell may be defined in the secondary node modification request response message, and the PDCP SN length change indication of the first bearer may be carried in the new cell. The PDCP SN length change indication may be carried by 1bit, e.g., 1 represents a PDCP SN length change and 0 represents no change in PDCP SN length.

S1106: the MN01 generates second configuration information for the first bearer based on the PDCP SN length change indication for the first bearer.

If an entity (e.g., PDCP entity, RLC entity, or MAC entity) is not on MN01 before changing the bearer type and the entity is on MN01 after changing the bearer type, the second configuration information on the first bearer may include additional configuration information of the entity; if an entity (e.g., PDCP entity, RLC entity, or MAC entity) is on MN01 before changing bearer type and on MN01 after changing bearer type, the second configuration information on the first bearer may include the release and add configuration information of the entity; the second configuration information on the first bearer may include the released configuration information of an entity (e.g., PDCP entity, RLC entity, or MAC entity) on MN01 if the entity was on MN01 before the change of bearer type and the entity was not on MN01 after the change of bearer type.

Before changing the bearer type, the first bearer is terminated at the SN, that is, the first bearer is modified from one of an SN-terminated MCG bearer, an SN-terminated SCG bearer or an SN-terminated split bearer to another one of the SN-terminated MCG bearer, the SN-terminated SCG bearer or the SN-terminated split bearer, and the second configuration information of the first bearer may include the following:

as a first example, the second configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, configuration information of release and addition of the RLC entity and the MAC entity.

As a second example, the second configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, configuration information of release of the RLC entity and the MAC entity.

As a third example, the second configuration information of the first bearer may include configuration information of the RLC entity and the MAC entity, for example, added configuration information of the RLC entity and the MAC entity.

For example, the bearer type of the first bearer is an MCG bearer terminated by an SN before the bearer type is modified, and the bearer type of the first bearer is a split bearer terminated by an SN after the bearer type is modified; or the bearer type of the first bearer is a split bearer terminated by the SN before the bearer type is modified, the bearer type of the first bearer is an MCG bearer terminated by the SN after the bearer type is modified, and the second configuration information of the first bearer may include configuration information of release and addition of the RLC entity and the MAC entity.

For example, the bearer type of the first bearer is an SN-terminated MCG bearer or an SN-terminated split bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated SCG bearer after the bearer type is modified, and the second configuration information of the first bearer may include configuration information of release of the RLC entity and the MAC entity.

For example, the bearer type of the first bearer is an SN-terminated SCG bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated MCG bearer or an SN-terminated split bearer after the bearer type is modified, and the second configuration information of the first bearer may include the added configuration information of the RLC entity and the MAC entity.

as a first example, the second configuration information of the first bearer may include configuration information of the PDCP entity, e.g., configuration information of a deletion of the PDCP entity.

As a second example, on the basis of the first example, the second configuration information of the first bearer may further include configuration information of the RLC entity and the MAC entity, for example, configuration information of release and addition of the RLC entity and the MAC entity.

As a third example, on the basis of the first example, the second configuration information of the first bearer may further include configuration information of the RLC entity and the MAC entity, for example, added configuration information of the RLC entity and the MAC entity.

As a fourth example, on the basis of the first example, the second configuration information of the first bearer may further include configuration information of the RLC entity and the MAC entity, for example, configuration information of release of the RLC entity and the MAC entity.

For example, the bearer type of the first bearer is an SCG bearer terminated by the MN before the bearer type is modified, the bearer type of the first bearer is an SCG bearer terminated by the SN after the bearer type is modified, the second configuration information of the first bearer may include the deleted configuration information of the PDCP entity or may not include the deleted configuration information of the PDCP entity, and at this time, the MN01 may not generate the second configuration information.

For example, the bearer type of the first bearer is an MCG bearer or a split bearer terminated by an MN before the bearer type is modified, the bearer type of the first bearer is an SN-terminated MCG bearer or a split bearer after the bearer type is modified, and the second configuration information of the first bearer may include deleted configuration information of a PDCP entity or may not include deleted configuration information of the PDCP entity, and configuration information of a release and an addition of an RLC entity and an MAC entity.

For example, the bearer type of the first bearer is an MN-terminated MCG bearer or a split bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated SCG bearer after the bearer type is modified, and the second configuration information of the first bearer may include deleted configuration information of the PDCP entity or may not include deleted configuration information of the PDCP entity and configuration information of release of the RLC entity and the MAC entity.

For example, the bearer type of the first bearer is an MN-terminated SCG bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated MCG bearer or an SN-terminated split bearer after the bearer type is modified, and the second configuration information of the first bearer may include deleted configuration information of the PDCP entity or not include deleted configuration information of the PDCP entity and added configuration information of the RLC entity and the MAC entity.

S1107: MN01 sends an RRC connection reconfiguration message to terminal 21.

The RRC connection reconfiguration message may include a bearer identification of the first bearer, first configuration information of the first bearer, and second configuration information of the first bearer.

S1108: the terminal 21 sends an RRC connection reconfiguration complete message to the MN 01.

S1109: MN01 sends a secondary node modification confirm (SN modification confirm) message to SN 11.

FIG. 12a is a diagram illustrating another embodiment of changing the length of PDCP SNs.

The first bearer may terminate at the SN, and the SN11 may request the MN01 to initiate a secondary node modification procedure to modify the bearer type of the first bearer, where the modified first bearer terminates at the SN, that is, the bearer type terminated by the SN may be modified into two other bearer types terminated by SNs.

S1201: the SN11 generates a second PDCP SN length for the first bearer.

S1202: the SN11 generates a PDCP SN length change indication for the first bearer when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer.

S1203: SN11 sends a secondary node modification application message to MN 01.

The secondary node modification application message includes a PDCP SN length change indication for the first bearer.

Optionally, a new cell may be defined in the secondary node add request response message, and the PDCP SN length change indication of the first bearer may be carried in the new cell. The PDCP SN length change indication may be carried by 1bit, e.g., 1 represents a PDCP SN length change and 0 represents no change in PDCP SN length.

S1204: MN01 sends a secondary node modification request message to SN 11.

S1205: the SN11 generates first configuration information for the first bearer.

S1206: SN11 sends a secondary node modification request response message to MN 01.

S1207: the MN01 generates second configuration information for the first bearer based on the PDCP SN length change indication for the first bearer.

S1208: MN01 sends an RRC connection reconfiguration message to terminal 21.

S1209: the terminal 21 sends an RRC connection reconfiguration complete message to the MN 01.

S1210: MN01 sends a secondary node modification confirm (SN modification confirm) message to SN 11.

Other contents of S1201-S1210 may refer to the relevant contents in fig. 11, for example, the relevant contents about "when the bearer type is changed, the first bearer may be terminated with SN".

In the first scheme, PDCP SN length change indication is interacted by MN01 and SN01, so that MN01 and SN11 generate the release and added configuration information of the bearer for terminal 21, and PDCP SN length change is completed. In addition, when the length of the PDCP SN may be 12 bits or 18 bits, after receiving the PDCP SN length change instruction, the MN01 can obtain a new PDCP SN length by combining the PDCP SN length stored in the MN01, so that the MN01 can subsequently determine whether the length of the PDCP SN has changed, so as to subsequently generate release and increase configuration information for a bearer.

The second scheme is explained below.

Figure 12b is a diagram of another embodiment for changing the length of the PDCP SN.

S12b 01: the SN11 generates a second PDCP SN length for the first bearer.

Reference may be made to the relevant contents in S801.

S12b 02: the SN11 determines whether there is a change in the PDCP SN length.

The PDCP SN length changes when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer.

As a first implementation manner, when the PDCP SN length of the first bearer is the first PDCP SN length, the first bearer is terminated at SN, and the SN11 may obtain the first PDCP SN length.

As a second implementation manner, when the PDCP SN length of the first bearer is the first PDCP SN length, the first bearer is terminated at the MN, and the method may further include that the MN01 sends the first PDCP SN length to the SN11, for example, the first PDCP SN length may be sent through an auxiliary node add request message and an auxiliary node modify request message.

Other contents may refer to the related contents in S802.

When the length of the PDCP SN changes, the method can further comprise the steps of S1203, S1205-S1208.

S12b 03: the SN11 generates first configuration information for the first bearer.

Optionally, S1203 may be concurrent with S1201, that is, when the SN11 generates the first configuration information of the first bearer, the second PDCP SN length of the first bearer may be generated.

Reference may be made to S804 in fig. 8, which is not described in detail herein.

S12b 04: the SN11 sends the second PDCP SN length for the first bearer to the MN 01.

For example, the SN11 may send the second PDCP SN length of the first bearer via a secondary node add request message, a secondary node modify request message, or a secondary node modify apply message.

As a first example, the SN11 may transmit a second PDCP SN length to the MN01 when it is judged in S1202 that the PDCP SN length has changed.

As a second example, the SN11 can send the second PDCP SN length to the MN01 after generating the second PDCP SN length. That is, the SN11 can send a second PDCP SN length to MN01, with or without a change in PDCP SN length.

The MN01 can read the second PDCP SN length of the first bearer, and optionally, the MN01 can save the second PDCP SN length of the first bearer.

For example, the SN11 can send the second PDCP SN length to MN01, carried in a cell that MN01 would read.

For example, the SN11 may define a new cell that includes a second PDCP SN length, which the MN01 may read.

Referring to section 9.1.3.2 of 3GPP TS36.423V15.1.0, SN11 may carry configuration information generated by SN11 for terminal 21 in the secondary node addition request response message, for example, the configuration information may be a container (container) in which the second PDCP SN length may be included, but at this time MN01 is not required to read the contents of the container, so MN01 does not read the second PDCP SN length carried in the container.

Here, MN01 may read the second PDCP SN length by defining a new cell or by carrying the second PDCP SN length in a cell that MN01 will read, so that MN01 may determine whether the PDCP SN length has changed, thereby generating the release and added configuration information of the first bearer for terminal 21.

S12b 05: the SN11 sends first configuration information of the first bearer to the MN 01.

Optionally, S1204 and S1205 may be simultaneous, for example, the second PDCP SN length and the first configuration information of the first bearer may be sent to MN01 through the same message, for example, a secondary node add request response message or a secondary node modify request response message.

S12b 06: MN01 sends first configuration information of the first bearer to terminal 21.

S12b 07: the MN01 determines whether the PDCP SN length has changed.

As a first implementation manner, when the PDCP SN length of the first bearer is the first PDCP SN length, the first bearer is terminated at an SN, and the SN11 may send the first PDCP SN length of the first bearer to the MN01, which may specifically refer to the relevant content of S1203.

As a second implementation manner, when the PDCP SN length of the first bearer is the first PDCP SN length, the first bearer is terminated at the MN, and the MN01 may obtain the first PDCP SN length of the first bearer.

S12b 08: MN01 is configured to generate second configuration information for the first bearer.

Reference may be made to the relevant contents of S807 in fig. 8.

S12b 09: MN01 sends the second configuration information of the first bearer to terminal 31.

Reference may be made to relevant content of S808 in fig. 8.

Alternatively, S12b09 and S12b06 may be simultaneous, for example, SN11 sends a message to MN01, the message including the first configuration information of the first bearer and the second configuration information of the first bearer, for example, the message is an RRC connection reconfiguration message.

In the second scheme, MN01 and SN11 respectively determine whether the PDCP SN length changes, so that MN01 and SN11 generate configuration information of release and addition of the bearer for terminal 21, and complete PDCP SN length change. In addition, when there are more than 3 possibilities of PDCP SN length, for example, 3, 4 or more, there may be more possibilities of PDCP SN length variation, the latest PDCP SN length can be known through both MN01 and SN11, and MN01 and SN11 can more accurately determine whether there is a variation in PDCP SN length.

The third embodiment will be explained below.

The PDCP SN lengths corresponding to the bearer types may be configured, and the MN01 and the SN11 may store the PDCP SN lengths corresponding to each bearer type, and when the bearer type changes, the MN01 or the SN11 may know whether the PDCP SN length changes, and when the change occurs, the MN01 and the SN11 generate configuration information of release and addition of the bearer for the terminal 21.

For example, bearers related to single air interface resources, such as MN terminated or SN terminated MCG bearers, MN terminated or SN terminated SCG bearers, may be configured to have a PDCP SN length, for example, a 12-bit PDCP SN length; bearers related to dual air interface resources, such as MN terminated or SN terminated split bearers, may be configured as another PDCP SN length, such as 18bit PDCP SN length. The following description is given by way of example, and it will be understood by those skilled in the art that the following applies equally to other cases.

Figure 13 is a diagram of another embodiment for changing the length of PDCP SNs.

S1301: the SN11 determines whether there is a change in the PDCP SN length.

For example, SN11 may be determined by: (1) judging whether the bearer type of the first bearer changes or not, and (2) judging whether the PDCP SN length corresponding to the bearer type before the change and the PDCP SN length corresponding to the bearer type after the change or not. The SN11 may receive the bearer type of the first bearer from MN01, e.g., may be via a secondary node addition request message, a secondary node modification request message.

For example, the bearer type of the first bearer changes, the first bearer is an MCG bearer terminated by the MN before the change, and the second bearer is a split bearer terminated by the SN, and the SN11 indicates that the PDCP SN length of the MCG bearer terminated by the MN is 12 bits, and the PDCP SN length of the split bearer terminated by the SN is 18 bits, so that the PDCP SN length changes.

S1302: the SN11 generates first configuration information for the first bearer for the terminal 21.

The first configuration information of the first bearer may include configuration information of an entity of the first bearer at SN11 when the PDCP SN length changes, e.g., when the entity is on SN11 before the PDCP SN length change and is not on SN11 before the PDCP SN length change, the first configuration information may include release information of the entity; the first configuration information may include configuration information of a release and an addition of the entity when the entity is on the SN11 before the PDCP SN length is changed and on the SN11 before the PDCP SN length is changed; the first configuration information may include additional information of the entity, which may be a PDCP entity, an RLC entity, or a MAC entity, when the entity is not at the SN11 before the PDCP SN length change and at the SN11 before the PDCP SN length change.

Reference may be made to the relevant contents of fig. 8-11.

S1303: the SN11 sends first configuration information of the first bearer to the MN 01.

For example, the first configuration information of the first bearer may be sent by the secondary node adding the request response message or the secondary node modifying the request response message.

S1304: the MN01 determines whether the PDCP SN length has changed.

Reference may be made to the relevant contents in S1301.

S1305: MN01 generates second configuration information for the first bearer for terminal 21.

The second configuration information of the first bearer may include configuration information of an entity of the first bearer at MN01 when the PDCP SN length changes, e.g., when the entity is on MN01 before the PDCP SN length change and not on MN01 before the PDCP SN length change, the second configuration information may include release information of the entity; the second configuration information may include the release and add configuration information of the entity when the entity is on MN01 before the PDCP SN length changes and on MN01 before the PDCP SN length changes; the second location information may include additional information of the entity, which may be a PDCP entity, an RLC entity, or a MAC entity, when the entity is not at MN01 before the PDCP SN length change and at MN01 before the PDCP SN length change.

Reference may be made to the relevant contents of fig. 8-11.

S1306: the MN01 transmits first configuration information of the first bearer and second configuration information of the first bearer to the terminal 21.

For example, the first configuration information of the first bearer and the second configuration information of the first bearer may be transmitted through an RRC connection reconfiguration message.

In the three schemes, MN01 or SN11 may adopt a CU-DU architecture, a part of protocol layers may be deployed on CUs, a part of protocol layers may be deployed on DUs, and the following description takes the example that a PDCP layer is deployed on CUs, and an RLC layer, a MAC layer, and a physical layer are deployed on DUs as examples.

In the present embodiment, actions sent or received by SN11 may be performed by CU 1111. The configuration information of the PDCP entity in the first configuration information of the first bearer generated by the SN11 is generated by the CU1111, and the configuration information of the RLC entity or the configuration information of the MAC entity in the first configuration information is generated by the DU 1121.

CU1111 may generate a PDCP SN length change indication, CU1111 may send the PDCP SN length change indication of the first bearer to DU1121, and DU1121 generates configuration information of an RLC entity or configuration information of MAC according to the PDCP SN length change indication of the first bearer. CU1111 may send a PDCP SN length change indication of the first bearer to MN01, e.g. CU 0111.

CU1111 may generate a PDCP SN length, CU1111 may send the PDCP SN length of the first bearer to DU1121, and DU1121 determines whether the PDCP SN length is changed according to the received PDCP SN length of the first bearer, thereby generating configuration information of an RLC entity or configuration information of a MAC. CU1111 may send the PDCP SN length of the first bearer to MN01, e.g. to CU 0111.

In the embodiment of the present application, the action sent or received by MN01 may be performed by CU 0111. The configuration information of the PDCP entity in the second configuration information of the first bearer generated by MN01 is generated by CU0111, the configuration information of the RLC entity or the configuration information of the MAC entity in the second configuration information is generated by DU0121, CU0111 may send a PDCP SN length change instruction of the first bearer to DU0112, and DU0112 generates the configuration information of the RLC entity or the configuration information of the MAC according to the PDCP SN length change instruction of the first bearer. CU0111 may receive an indication of a change in PDCP SN length of the first bearer from SN11, e.g., CU1111, and may then send an indication of a change in PDCP SN length of the first bearer to DU 0112.

CU0111 may generate a PDCP SN length, CU0111 may send the PDCP SN length of the first bearer to DU0121, and DU0121 determines whether the PDCP SN length is changed according to the received PDCP SN length of the first bearer, and generates configuration information of an RLC entity or configuration information of an MAC. CU0111 may send the PDCP SN length of the first bearer to SN11, e.g., to CU 1111.

FIG. 14 is a diagram illustrating an embodiment of changing the length of PDCP SNs under a CU-DU architecture. The CU1111 and the DU1121 are taken as examples for explanation, and those skilled in the art can understand that the same applies to CU0111 and DU 0121.

S1401: CU1111 generates configuration information of the PDCP entity.

S1402: CU1111 sends a PDCP SN length change indication of the first bearer to DU 1121.

Or, as another embodiment, in 1402, CU1111 sends the PDCP SN length of the first bearer to DU1121, CU1111 may carry the PDCP SN length of the first bearer in a cell read by DU1121, for example, CU1111 may define a new cell, the new cell carries the PDCP SN length of the first bearer, and DU1121 reads the PDCP SN length of the first bearer from the cell.

S1403: the DU1121 generates configuration information of the RLC entity and configuration information of the MAC entity.

The DU1121 may generate configuration information of the RLC entity and configuration information of the MAC entity according to the PDCP SN length change indication.

As another embodiment, the DU1121 may read the PDCP SN length sent by the CU1111, and the DU1121 may determine whether the PDCP SN length is changed according to the received PDCP SN length of the first bearer, and if the PDCP SN length is changed, generate configuration information of the RLC entity or configuration information of the MAC.

S1404: the DU1121 transmits configuration information of the RLC entity and configuration information of the MAC entity to the CU 1111.

Here, the configuration information of the PDCP entity may include released configuration information, added configuration information, or released and added configuration information of the PDCP entity in the embodiment of the present application.

Here, the configuration information of the RLC entity may include released configuration information, added configuration information, or released and added configuration information of the RLC entity in the embodiment of the present application.

Here, the configuration information of the MAC entity may include released configuration information, added configuration information, or released and added configuration information of the MAC entity in the embodiment of the present application.

Reference may be made to relevant contents in fig. 8 to fig. 13, which are not described herein again.

Having described the method flow diagrams of embodiments of the present application, it is to be understood that MN01 may have functional elements corresponding to the steps of the MN01 method or flow, and SN11 may have functional elements corresponding to the steps of the SN11 method or flow.

For example, the SN11 may include a generating unit that may generate a second PDCP SN length of a first bearer, and a communication unit that may further generate a PDCP SN length change indication of the first bearer when the second PDCP SN length of the first bearer is different from a first PDCP SN length of the first bearer, and may send the PDCP SN length change indication of the first bearer to a MN. Optionally, the generating unit may be further configured to generate first configuration information of the first bearer, and the communication unit is configured to send the first configuration information of the first bearer to MN 01.

For example, the SN11 may include a communication unit that may be configured to receive an indication of a change in length of a PDCP SN of a first bearer from a SN, and a holding unit that may be configured to hold the indication of the change in length of the PDCP SN of the first bearer. Optionally, the SN11 may further include a generating unit, the generating unit may be configured to generate the second configuration information of the first bearer, and the communication unit may send the first configuration information of the first bearer and the second configuration information of the first bearer to the terminal 21.

The following describes an apparatus or device in an embodiment of the present application.

Fig. 15 is a schematic structural diagram of an access network device. MN01 or SN11 may refer to the structure shown in fig. 15.

The access network equipment includes at least one processor 1511, at least one memory 1512, at least one transceiver 1513, at least one network interface 1514, and one or more antennas 1515. The processor 1511, memory 1512, transceiver 1513, and network interface 1514 are coupled, such as by a bus. The antenna 1515 is connected to the transceiver 1513. The network interface 1514 is used to connect the access network device to other communication devices via a communication link, for example the access network device to the core network element 101 via an S1 interface. In the embodiment of the present application, the connection may include various interfaces, transmission lines, buses, and the like, which is not limited in this embodiment.

The processor in the embodiment of the present application, for example, the processor 1511, may include at least one of the following types: a general-purpose Central Processing Unit (CPU), a Digital Signal Processor (DSP), a microprocessor, an Application-Specific integrated circuit (ASIC), a Microcontroller (MCU), a Field Programmable Gate Array (FPGA), or an integrated circuit for implementing logic operations. For example, the processor 1111 may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. The at least one processor 1111 may be integrated in one chip or located on multiple different chips.

The memory in the embodiment of the present application, for example, the memory 1512, may include at least one of the following types: read-only memory (ROM) or other types of static memory devices that may store static information and instructions, Random Access Memory (RAM) or other types of dynamic memory devices that may store information and instructions, and may also be Electrically erasable programmable read-only memory (EEPROM). In some scenarios, the memory may also be, but is not limited to, a compact disk-read-only memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.

The memory 1512, which may be separate, is coupled to the processor 1511. Optionally, the memory 1512 may also be integrated with the processor 1511, for example, within a chip. The memory 1512 can store program codes for executing the technical solutions of the embodiments of the present application, and the processor 1511 controls execution of the program codes, and the executed computer program codes may also be regarded as drivers of the processor 1511. For example, the processor 1511 is configured to execute the computer program code stored in the memory 1512, so as to implement the technical solution in the embodiment of the present application.

A transceiver 1513 may be used to support the reception or transmission of radio frequency signals between the access network device and the terminal, and the transceiver 1513 may be coupled to an antenna 1515. The transceiver 1513 includes a transmitter Tx and a receiver Rx. Specifically, one or more antennas 1515 may receive radio frequency signals, and the receiver Rx of the transceiver 1513 is configured to receive the radio frequency signals from the antennas, convert the radio frequency signals into digital baseband signals or digital intermediate frequency signals, and provide the digital baseband signals or digital intermediate frequency signals to the processor 1511, so that the processor 1511 performs further processing on the digital baseband signals or digital intermediate frequency signals, such as demodulation processing and decoding processing. In addition, the transmitter Tx in the transceiver 1513 is also used to receive a modulated digital baseband signal or a digital intermediate frequency signal from the processor 1511, convert the modulated digital baseband signal or the digital intermediate frequency signal into a radio frequency signal, and transmit the radio frequency signal through the one or more antennas 1515. Specifically, the receiver Rx may selectively perform one or more stages of down-mixing and analog-to-digital conversion processes on the rf signal to obtain a digital baseband signal or a digital intermediate frequency signal, wherein the order of the down-mixing and analog-to-digital conversion processes is adjustable. The transmitter Tx may selectively perform one or more stages of up-mixing and digital-to-analog conversion processes on the modulated digital baseband signal or the modulated digital intermediate frequency signal to obtain the rf signal, where the order of the up-mixing and the digital-to-analog conversion processes is adjustable. The digital baseband signal and the digital intermediate frequency signal may be collectively referred to as a digital signal.

When the access network device is SN11, the access network device may implement the method performed by SN11 in the embodiment of the present application, for example, the processor 1111 may generate a second PDCP SN length of the first bearer, a PDCP SN length change indication of the first bearer, and first configuration information of the first bearer, the processor 1111 may send the PDCP SN length change indication of the first bearer and the first configuration information of the first bearer to MN01 through the network interface 1114, and the memory 1112 may store the PDCP SN length of the first bearer, for example, the first PDCP SN length and/or the second PDCP SN length. Other steps of the access network device implemented by the components thereof may refer to the method performed by the SN11 in the embodiment of the present application, and are not described herein again.

When the access network device is MN01, the access network device may implement the method performed by MN01 in this embodiment of the present application, for example, the PDCP SN length change indication of the first bearer and the first configuration information of the first bearer may be received through network interface 1114, processor 1111 may generate the second configuration information of the first bearer according to the PDCP SN length change indication of the first bearer, antenna 1115 may send the first configuration information of the first bearer and the second configuration information of the first bearer to terminal 21, and memory 1112 may store the PDCP SN length of the first bearer, for example, the first PDCP SN length and/or the second PDCP SN length. Other steps implemented by the access network device through its components may refer to the method performed by MN01 in this embodiment, and are not described herein again.

Fig. 16 is a schematic structural diagram of a terminal according to an embodiment of the present application. The structure of the terminal 21 can refer to the structure shown in fig. 16.

The terminal includes at least one processor 1611, at least one transceiver 1612, and at least one memory 1613. The processor 1611, memory 1613, and transceiver 1612 are connected. Optionally, the terminal 21 may also include an output device 1614, an input device 1615, and one or more antennas 1616. The antenna 1616 is coupled to the transceiver 1612, and the output device 1614 and the input device 1615 are coupled to the processor 1611.

The transceiver 1612, memory 1613, and antenna 1616 may perform similar functions as described with respect to fig. 15.

The processor 1611 may be a baseband processor or a CPU, and the baseband processor and the CPU may be integrated together or separated.

The processor 1611 may be used to implement various functions for the terminal, such as processing communication protocols and communication data, or controlling the entire terminal device, executing software programs, and processing data of the software programs; or to assist in completing computational processing tasks, such as processing of graphical images or audio, etc.; or processor 1211 may be used to perform one or more of the functions described above

An output device 1614 is in communication with the processor 1611 and may display information in a variety of ways. For example, the output device 1214 may be a Liquid Crystal Display (LCD), a Light Emitting Diode (LED) Display device, a Cathode Ray Tube (CRT) Display device, a projector (projector), or the like. The input device 1615 is in communication with the processor 1611 and may accept user input in a variety of ways. For example, the input device 1615 may be a mouse, a keyboard, a touch screen device, a sensing device, or the like.

When the terminal is the terminal 21, the access network device may implement the method performed by the terminal 21 in the embodiment of the present application, for example, may receive the first configuration information of the first bearer and the second configuration information of the first bearer from the MN01 through the antenna 1616. Other steps of the terminal implemented by the components thereof may refer to the method executed by the terminal 21 in the embodiment of the present application, and are not described herein again.

Fig. 17 is a schematic structural diagram of an apparatus 1700 according to an embodiment of the present disclosure.

The communication device 1700 includes a processor 1701 and a communication interface 1702, wherein the processor 1701 is coupled to the communication interface 1702, and optionally, the communication device 1700 may further include a memory 1703, and the memory 1703 is coupled to the processor 1701 and the communication interface 1702.

The processor 1701 may include at least one of the following types: a general-purpose Central Processing Unit (CPU), a Digital Signal Processor (DSP), a microprocessor, an Application-Specific Integrated Circuit (ASIC), a Microcontroller (MCU), a Field Programmable Gate Array (FPGA), or an Integrated Circuit for implementing logic operations. For example, the processor 1711 may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. The at least one processor 1711 may be integrated in one chip or located on multiple different chips.

The memory 1703 may include at least one of the following types: read-only memory (ROM) or other types of static memory devices that may store static information and instructions, Random Access Memory (RAM) or other types of dynamic memory devices that may store information and instructions, and Electrically erasable programmable read-only memory (EEPROM). In some scenarios, the memory may also be, but is not limited to, a compact disk-read-only memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.

The communication interface 1702 may be capable of transceiving for communicating with other communication devices or other devices within a communication device.

The memory 1703 may be separate and coupled to the processor 1701 via a communication bus. The memory 1703 may also be integrated with the processor 1701.

The apparatus 1700 may be a MN (e.g., MN01), a chip in a MN (e.g., MN01), a chip in a SN (e.g., SN11), a chip in a SN (e.g., SN11), a chip in a CU (e.g., CU0111 or CU1111), a chip in a DU (e.g., DU0121 or DU 1121).

When the apparatus 1700 is a chip in MN01 or MN01, the memory 1703 may store therein instructions and data of a method executed by MN01 in the embodiment of the present application, and the processor 1701 may read and execute the instructions and data of the method in the memory 1703, thereby implementing the method executed by MN01 in the embodiment of the present application. When the apparatus 1700 is a MN01, the communication interface 1703 may include an interface to other access network devices, such as an interface to a SN11, and may also include an antenna and a transceiver, such as antenna 1515 and transceiver 1513 in fig. 15, and when the apparatus 1700 is a chip in MN01, the communication interface 1703 may be an input or output interface, pin or circuit, etc., and the processor 1701 and the memory 1703 may be integrated together.

When the device 1700 is a chip in the SN11 or the SN11, the memory 1703 may store therein instructions and data of a method executed by the SN11 in the embodiment of the present application, and the processor 1701 may read and execute the instructions and data of the method in the memory 1703, thereby implementing the method executed by the SN11 in the embodiment of the present application. When the apparatus 1700 is an SN11, the communication interface 1703 may include interfaces with other access network devices, such as an MN01, and may also include an antenna and a transceiver, such as antenna 1515 and transceiver 1513 in fig. 15, when the apparatus 1700 is a chip in an SN11, the communication reception 1703 may be an input or output interface, pin or circuit, etc., and the processor 1701 and the memory 1703 may be integrated together.

When the apparatus 1700 is a chip in CU0111 (or CU1111) or CU1111 (or CU1111), the memory 1703 may store instructions and data of the method executed by CU0111 (or CU1111) in the embodiment of the present application, and the processor 1701 may read and execute the instructions and data of the method in the memory 1703 to implement the method executed by CU0111 (or CU1111) in the embodiment of the present application. When the apparatus 1700 is CU0111 (or CU1111), the communication interface 1703 may include an interface with DU0121 (or DU1121) and may also include an interface with CU1111 (or CU 0111); when the apparatus 1700 is a chip in CU0111 (or CU1111), the communication reception 1703 may be an input or output interface, pin or circuit, etc., and the processor 1701 and the memory 1703 may be integrated.

When the apparatus 1700 is a chip in the DU0121 (or the DU1121) or the DU0121 (or the DU1121), the memory 1703 may store instructions and data of the method executed by the DU0121 (or the DU1121) in the embodiment of the present application, and the processor 1701 may read and execute the instructions and data of the method in the memory 1703, thereby implementing the method executed by the DU0121 (or the DU1121) in the embodiment of the present application. When the apparatus 1700 is a DU0121 (or a DU1121), the communication interface 1703 may include an interface with CU0111 (or CU1111), and may further include a transceiver and an antenna, which may be used to transmit and receive data to and from the terminal 21, such as first configuration information of the first bearer and second configuration information of the first bearer; when the apparatus 1700 is a chip in CU0111 (or CU1111), the communication reception 1703 may be an input or output interface, pin or circuit, etc., and the processor 1701 and the memory 1703 may be integrated.

The embodiment of the application also provides a computer readable storage medium. The methods described in the above method embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media may include computer storage media and communication media, and may include any medium that can communicate a computer program from one place to another. A storage media may be any available media that can be accessed by a computer.

As an alternative design, a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a network node, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

The embodiment of the application also provides a computer program product. The methods described in the above method embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. If implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The procedures or functions described in the above method embodiments are generated in whole or in part when the above computer program instructions are loaded and executed on a computer. The computer may be a general purpose computer, a special purpose computer, a computer network, a network appliance, a user device, or other programmable apparatus.

Fig. 18-20 below describe a scheme for changing the length of the PDCP SN, in which, when the length of the PDCP SN changes, MN01 may assign a new bearer identity to the bearer, and then MN01 and SN11 generate configuration information of a release of an entity corresponding to the old bearer identity of the bearer and configuration information of an addition of an entity corresponding to the new bearer identity of the bearer, and terminal 21 performs the release of the entity corresponding to the old bearer identity of the bearer and the addition of the entity corresponding to the new bearer identity of the bearer. The method is described below from the perspective of the primary node and the secondary node.

The following M1 method may be performed by a master node or a chip in a master node, the M1 method comprising:

m101: and acquiring the second PDCP SN length of the first bearer.

Optionally, the second PDCP SN length of the first bearer may be generated or determined by the primary node, or the second PDCP SN length of the first bearer may be received from the secondary node.

M102: and when the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer, determining a second bearer identification of the first bearer.

The first PDCP SN length of the first bearer may be a length of the first bearer stored by the master node before the second PDCP SN length of the first bearer is acquired.

Optionally, the second bearer identity of the first bearer is different from the first bearer identity of the first bearer.

Optionally, the first bearer identifier of the first bearer may be a bearer identifier of the first bearer when the PDCP SN length of the first bearer is the first PDCP SN length.

Optionally, the first bearer identifier of the first bearer may be a bearer identifier of the first bearer stored by the master node.

M103: and sending the second bearer identification of the first bearer to the secondary node.

Optionally, the method may further include M104-M106.

M104: and receiving the secondary node configuration information of the first bearer from the secondary node.

Optionally, the secondary node configuration information of the first bearer may include added configuration information of an entity on the secondary node corresponding to the second bearer identifier of the first bearer.

Optionally, the secondary node configuration information of the first bearer may include configuration information of release of an entity on the secondary node corresponding to the first bearer identifier of the first bearer.

M105: and generating main node configuration information of the first bearer.

Optionally, the primary node configuration information of the first bearer may include added configuration information of an entity on the primary node corresponding to the second bearer identifier of the first bearer.

Optionally, the primary node configuration information of the first bearer may include configuration information of a release of an entity on the primary node corresponding to the first bearer identifier of the first bearer.

M106: and sending the auxiliary node configuration information of the first bearer and the main node configuration information of the first bearer to the terminal.

The following M2 method may be performed by the secondary node or a chip in the secondary node.

M201: a second PDCP SN length for the first bearer is determined.

M201 is optional.

M202: a second bearer identification of the first bearer is received from the master node.

M203: and sending the configuration information of the auxiliary node of the first bearer to the main node.

As further described below in conjunction with fig. 18-20.

FIG. 18 is a diagram illustrating an embodiment of changing the length of PDCP SNs, in which an EN-DC scenario is taken as an example.

S1801: MN01 sends a first request message to SN 11.

Optionally, the first request message may be a first secondary node addition request message or a first secondary node modification request message.

For example, the first request message may be a first secondary node addition request message, before the MN01 sends the secondary node addition request message to the SN11, the bearer type of the first bearer may be an MCG bearer terminated by the MN, MN01 may determine the bearer type of the first bearer after adding the secondary node, and the first bearer may be terminated at the SN after adding the secondary node, that is, the PDCP entity of the first bearer after adding the secondary node is on the SN11, for example, the bearer type of the first bearer after adding the secondary node is an MCG bearer terminated by the SN, an SCG bearer terminated by the SN, or a split bearer terminated by the SN.

For example, the first request message may be a first secondary node modification request message, the first secondary node modification request message may indicate to modify the bearer type of the first bearer, the bearer type of the first bearer may be terminated at the MN or at the SN before the MN01 sends the secondary node modification request message to the SN11, the MN01 may decide to modify the bearer type of the first bearer, and the first bearer may be terminated at the SN after modifying the bearer type, that is, the PDCP entity of the first bearer after adding the secondary node is on the SN11, for example, the bearer type of the first bearer after adding the secondary node is an MCG bearer terminated at the SN, an SCG bearer terminated at the SN, or a split bearer terminated at the SN.

The first request message may include:

(1) MN01 assigns terminal 21 an Identity (ID) on the interface of terminal 21.

The interface is between MN01 and SN 11.

Wherein the ID of the terminal 21 on the interface allocated by the MN01 for the terminal 21 is used to identify the terminal 21 on the interface between the MN01 and the SN 11.

For example, in an EN-DC scenario, an interface between MN01 and SN11 is an X2 interface, and an ID allocated by MN01 for terminal 21 at the interface is an X2 Application Protocol (AP) ID.

For another example, in a dual connectivity (NR-E-UTRA dual connectivity, NE-DC) scenario of NGEN-DC, NR-DC and NR and E-UTRA, the interface between MN01 and SN11 is an Xn interface, and the ID allocated by MN01 to terminal 21 on the interface is XnAP ID. In the NR-DC, the network element 31 of the core network is 5GC, MN01 is gNB, and SN11 is gNB. In both NGEN-DC and NE-DC, the network element 31 of the core network is 5 GC.

(2) An evolved universal terrestrial radio access network (E-UTRAN) radio access bearer (E-RAB) ID of the first bearer.

(3) A first bearer identification of the first bearer.

(4) And after the bearer type is modified, the indication information of the bearer type of the first bearer is modified.

(5) And modifying the configuration information of the PDCP entity of the first bearer before the bearer type.

For example, before adding the SN11, the bearer type of the first bearer is an MN-terminated MCG bearer, and the configuration information of the PDCP entity of the first bearer is the configuration information of the PDCP entity of the MN-terminated MCG bearer.

The configuration information of the PDCP entity of the first bearer before the modification of the bearer type may be used to assist the SN11 in generating configuration information of a new PDCP entity.

The configuration information of the PDCP entity of the first bearer before the modification of the bearer type may include a first PDCP SN length of the first bearer, for example, the first PDCP SN length may be 12 bits, and the first PDCP SN length of the first bearer is the PDCP SN length of the first bearer before the SN11 is increased.

Here, the first PDCP SN length of the first bearer may include one or both of a first uplink PDCP SN length of the first bearer and a first downlink PDCP SN length of the first bearer, for example, the first PDCP SN length of the first bearer may be the first uplink PDCP SN length of the first bearer; alternatively, the first PDCP SN length of the first bearer may be the first downlink PDCP SN length of the first bearer; alternatively, the first PDCP SN length of the first bearer may be a first uplink PDCP SN length of the first bearer and a first downlink PDCP SN length of the first bearer. The first uplink PDCP SN length of the first bearer is the uplink PDCP SN length of the first bearer before the SN11 is increased; the first downlink PDCP SN length of the first bearer is the downlink PDCP SN length of the first bearer before the SN11 is increased.

For example, when the first REQUEST message is a first secondary node ADDITION REQUEST message, the first secondary node ADDITION REQUEST message may refer to the relevant contents of "secondary nb ADDITION REQUEST" in section 9.1.4.1 of the third Generation Partnership Project (3 GPP) Technical Specification (TS) 36.423V15.1.0, for example, the above-mentioned information (2) (3) may Be carried by the information element "E-RAB ID" and the information element "data radio bearer identification" ("DRBID") in the "E-rabto-Be-Added E-RAB Item" in the "SGNB ADDITION REQUEST".

For example, when the first REQUEST message is a first secondary node MODIFICATION REQUEST message, the first secondary node MODIFICATION REQUEST message may refer To the relevant contents of "SGNB MODIFICATION REQUEST" in section 9.1.4.5 of 3GPP TS36.423V15.1.0, e.g., the above-mentioned information (2) (3) may Be carried by the information element "E-RAB ID" and the information element "DRB ID" in the "E-RABs To Be attached Item" in the "SGNB MODIFICATION REQUEST".

S1802: the SN11 determines a second PDCP SN length for the first bearer.

The second PDCP SN length of the first bearer is the PDCP SN length of the first bearer after the SN11 is added.

For example, when the first request message is a secondary node addition request message, the secondary node addition request message may indicate that the PDCP entity of the first bearer is on SN11 after SN11 is added, and SN11 may generate a second PDCP SN length for the first bearer.

For example, when the first request message is a secondary node modification request message, the secondary node modification request message may indicate that the PDCP entity of the first bearer is at SN11 after modifying the bearer type, and SN11 may generate a second PDCP SN length for the first bearer.

The second PDCP SN length of the first bearer may be different from the first PDCP SN length of the first bearer.

For example, the second PDCP SN length of the first bearer may be 18 bits.

Optionally, the second PDCP SN length may include one or both of a second uplink PDCP SN length of the first bearer and a second downlink PDCP SN length of the first bearer, for example, the second PDCP SN length of the first bearer may be the second uplink PDCP SN length of the first bearer; or, the second PDCP SN length of the first bearer may be a second downlink PDCP SN length of the first bearer; alternatively, the second PDCP SN length of the first bearer may be a second uplink PDCP SN length of the first bearer and a second downlink PDCP SN length of the first bearer. The second uplink PDCP SN length of the first bearer is the uplink PDCP SN length of the first bearer before the modification of the bearer; the second downlink PDCP SN length of the first bearer is the downlink PDCP SN length of the first bearer before the bearer type is modified.

It should be noted that, in the embodiment of the present application, the second PDCP SN length is different from the first PDCP SN length, which may be understood as that the second uplink PDCP SN length is different from the first uplink PDCP SN length, or the second downlink PDCP SN length is different from the first downlink PDCP SN length.

S1803: SN11 sends a first request response message to MN 01.

Optionally, the first request response message may be an auxiliary node addition request response message or an auxiliary node modification request response message.

For example, when the first request message is a first auxiliary node addition request message, the first request response message is a first auxiliary node addition request response message; and when the first request message is a first auxiliary node modification request message, the first request response message is a first auxiliary node modification request response message.

The first request response message may include:

(1) terminal 21 ID on interface assigned by MN01 to terminal 21

Reference may be made to the relevant contents in the ID of the terminal 21 on the interface allocated to the terminal 21 by the MN01 in S1801.

(2) ID of terminal 21 on interface assigned by SN11 to terminal 21

Wherein, the interface is the interface between MN01 and SN 11.

Wherein the ID of the terminal 21 on the interface allocated by the SN11 for the terminal 21 is used to identify the terminal 21 on the interface between the SN11 and the MN 01.

For example, in an EN-DC scenario, the interface between MN01 and SN11 is an X2 interface, and the ID of the terminal 21 allocated by the SN11 for the terminal 21 on the interface is an X2AP ID.

For another example, in the scenarios of NGEN-DC, NR-DC, and NE-DC, the interface between MN01 and SN11 is an Xn interface, and the ID allocated by SN11 for terminal 21 on the interface is an XnAP ID.

(3) E-RAB identification of a first bearer

The E-RAB id of the first bearer carried in the first request message in S1801 may be referred to the relevant content of the E-RAB id in S1801.

(4) Second PDCP SN Length of first bearer

Optionally, when the SN11 determines that the second PDCP SN length of the first bearer is different from the first PDCP SN length of the first bearer, the SN11 may not generate the configuration information of the entity on the SN11 corresponding to the first bearer identifier of the first bearer, and the first response message may not include the configuration information of the entity on the SN11 corresponding to the first bearer identifier of the first bearer, and after receiving the second bearer identifier of the first bearer sent by the MN01, the SN11 issues the configuration information of the entity on the SN11 of the first bearer, so as to save communication resources.

S1804: MN01 sends a second request message to SN 11.

Optionally, the second request message may be a second secondary node addition request message or a second secondary node modification request message.

For example, when the first request message is a first secondary node addition request message, the second request message may be a second secondary node addition request message or a second secondary node modification request message.

For example, when the first request message is a first secondary node modification request message, the second request message may be a second secondary node modification request message.

In S1803, after receiving the first request response message sent by the SN11, the MN01 may obtain the second PDCP SN length of the first bearer, and when the first PDCP SN length of the first bearer is different from the second PDCP SN length of the first bearer, MN01 may compare the first PDCP SN length of the first bearer with the second PDCP SN length of the first bearer, which indicates that the SN11 changes the PDCP SN length of the first bearer, and MN01 may provide the second bearer identifier for the first bearer and send it to SN11, where the second bearer identifier of the first bearer is different from the first bearer identifier of the first bearer, and is used for the SN11 to perform bearer first release and then add processing.

The second request message may include:

(1) terminal 21 ID on interface assigned by MN01 to terminal 21

(2) E-RAB identification of a first bearer

May be the same as the E-RAB identity of the first bearer carried in the first request message in S1801 and the E-RAB identity of the first bearer carried in the first request response message in S1803.

(3) Second bearer identification of first bearer

The first bearer identity of the first bearer and the second bearer identity of the first bearer correspond to the same E-RAB identity.

Optionally, for the case that the second request message is a second secondary node modification request message, at this time, the E-RAB ID of the first bearer needs to be indicated in the bearer modification list in the second secondary node modification request message, and the second bearer identifier of the first bearer needs to be indicated at the same time.

For example, the cell "DRB ID" may Be added in the "E-RAB entry To Be Modified" ("E-RABs To Be Modified Item") in "SGNB MODIFICATION REQUEST" in section 9.1.4.5 of 3GPP TS36.423V15.1.0, and the specific cell structure may Be as shown in table 1 below:

TABLE 1

Optionally, the second request message may further include the first indication information.

As a first optional implementation manner, the first indication information is used to indicate that the bearer identifier of the first bearer is changed.

As a second alternative, the first indication information may indicate that the second request message is related to the first request message, where the second request message is related to the first request message may be understood as that the second request message modifies the bearer identity in the first request message, or the second request message is a continuation of the first request message.

As a third alternative, the first indication information may indicate that the second request message is related to the first request response message, where the second request message is related to the first request response message may be understood as that the second request message is generated based on the first request response message, or that the second request message is a reply to the first request response message.

As a fourth alternative, the first indication information may instruct the SN11 to generate the configuration information based on the second bearer identification of the first bearer. For example, when the second request message is a second secondary node modification request message, the first indication information that requires the SN11 to generate a complete set of configuration may be used to indicate that the SN11 generates a full configuration, rather than performing a difference (delta) configuration based on the configuration generated in S1803.

It should be noted that the first indication information may be carried by an existing cell, which may be used for MN01 to request the latest configuration on SN11 from SN 11. In the embodiment of the present application, the meaning of the information element may be expanded, and after the SN11 receives the second bearer identifier and the first indication information of the first bearer, a complete configuration may be generated for the terminal 21. For example, the existing cell may be the cell "SCG Configuration Query" in section 9.2.103 of 3GPP TS36.423V15.1.0.

Alternatively, a new cell may be defined, and the first indication information may be carried by the new cell, which is used to indicate the SN11 to generate a complete configuration for the terminal 21.

The foregoing is illustrative and not limiting.

In the foregoing various optional embodiments, the first indication information may specifically include one or both of an ID of the terminal 21 on the interface and a first bearer identifier of the first bearer, which are allocated to the terminal 21 by the SN11, or may be other than the ID and the first bearer identifier, which is not limited in this embodiment of the application.

Alternatively, the MN01 and the SN11 may negotiate that the first indication information may indicate the contents of the above-described various alternative embodiments when the second request message includes one or both of the ID of the terminal 21 on the interface allocated by the SN11 for the terminal 21 and the first bearer identification of the first bearer.

When the second request message is the second auxiliary node addition request message, the first indication information is carried in the second auxiliary node addition request message, so that after the SN11 receives the second auxiliary node addition request message, the SN11 can avoid that the second auxiliary node addition request message is regarded as an abnormal message without processing because the E-RAB identifiers of the first bearers carried by the second auxiliary node addition request message and the first auxiliary node addition request message are the same.

When the second request message is the second auxiliary node modification request message, the first indication information is carried in the second auxiliary node modification request message, so that it can be avoided that after the SN11 receives the second auxiliary node modification request message, the SN11 considers that the second auxiliary node modification request message is used for modifying the identifier of the first bearer, and thus only the bearer identifier of the first bearer is modified, for example, from the first bearer identifier to the second bearer identifier.

Optionally, the second request message may not include the first indication information, for example, the first request response message in S1803 does not include the configuration information of the entity on the SN11 corresponding to the first bearer identifier of the first bearer, which indicates that the SN11 has determined that the PDCP SN length change has occurred, but does not generate the configuration in S1803, at this time, the SN11 knows that a complete set of configurations needs to be generated at this time, and then no additional indication may be needed.

In connection with S1805-S1807, the following introduces that MN01 and SN11 generate, for terminal 21, configuration information of release of an entity corresponding to the first bearer identity and configuration information of addition of an entity corresponding to the second bearer identity.

S1805: the SN11 generates secondary node configuration information for the first bearer.

Upon receiving the second bearer identification of the first bearer, the SN11 may generate secondary node configuration information for the first bearer.

Optionally, the secondary node configuration information of the first bearer includes configuration information released by the PDCP entity corresponding to the first bearer identifier and configuration information added by the PDCP entity corresponding to the second bearer identifier.

For example, the bearer type of the first bearer is an MN-terminated MCG bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated MCG bearer after the bearer type is modified, and the configuration information of the secondary node of the first bearer may include release of a PDCP entity corresponding to the first bearer identifier and configuration information added by a PDCP entity corresponding to the second bearer identifier.

Optionally, the secondary node configuration information of the first bearer may further include configuration information added to the RLC entity corresponding to the second bearer identifier, and optionally, further include configuration information added to the logic entity corresponding to the second bearer identifier.

For example, the bearer type of the first bearer is an MN-terminated MCG bearer before the bearer type is modified, the bearer type of the first bearer is an SN-terminated SCG bearer or an SN-terminated split bearer after the bearer type is modified, and the configuration information of the secondary node of the first bearer may include configuration information of release of a PDCP entity corresponding to the first bearer identifier and configuration information of addition of a PDCP entity corresponding to the second bearer identifier, and configuration information of addition of an RLC entity corresponding to the second bearer identifier and configuration information of addition of an MAC entity corresponding to the second bearer identifier.

Optionally, the secondary node configuration information of the first bearer may further include configuration information of release of the RLC entity corresponding to the first bearer identifier and configuration information of addition of the RLC entity corresponding to the second bearer identifier, and optionally, further includes configuration information of release of a logical channel corresponding to the first bearer identifier and addition of a logical channel corresponding to the second bearer identifier.

For example, the bearer type of the first bearer is a split bearer terminated by MN before the bearer type is modified, the bearer type of the first bearer is an SCG bearer terminated by SN or a split bearer terminated by SN after the bearer type is modified, and the configuration information of the secondary node of the first bearer may include a PDCP entity and an RLC entity corresponding to the first bearer identifier, a PDCP entity and an RLC entity corresponding to the second bearer identifier, and optionally, may further include a logical channel release configuration corresponding to the first bearer identifier and a logical channel add configuration corresponding to the second bearer identifier.

S1806: the SN11 sends a second request response message to the MN 01.

The second request response message may include secondary node configuration information of the first bearer.

Optionally, the second request response message may be a second secondary node addition request response message or a second secondary node modification request response message.

For example, when the second request message is a second secondary node addition request message, the second request response message is a second secondary node addition request response message; and when the second request message is a second auxiliary node modification request message, the second request response message is a second auxiliary node modification request response message.

S1807: MN01 generates primary node configuration information for the first bearer.

Optionally, the primary node configuration information of the first bearer may include configuration information of a release of the RLC entity corresponding to the first bearer identifier of the first bearer and configuration information of an addition of the RLC entity corresponding to the second bearer identifier. Optionally, the method may further include a release configuration of the logical channel corresponding to the first bearer identifier and an addition configuration information of the logical channel corresponding to the second bearer identifier.

For example, the bearer type of the first bearer before the bearer type modification is an MCG bearer terminated by MN or an SPLIT bearer terminated by MN, and the bearer type of the first bearer after the bearer type modification is an SN-terminated MCG bearer or an SN-terminated SPLIT bearer, where the master node configuration information of the first bearer may include configuration information of release of an RLC entity corresponding to the first bearer identifier and configuration information of increase of an RLC entity corresponding to the second bearer identifier. Optionally, the method may further include a release configuration of the logical channel corresponding to the first bearer identifier and an addition configuration information of the logical channel corresponding to the second bearer identifier.

Optionally, the primary node configuration information of the first bearer may include configuration information of release of an RLC entity corresponding to the first bearer identifier of the first bearer. Optionally, release configuration information of the logical channel corresponding to the first bearer identifier may also be included.

For example, the bearer type of the first bearer before the bearer type is modified is an MCG bearer terminated by MN or an SPLIT bearer terminated by MN, the bearer type of the first bearer after the bearer type is modified is an SCG bearer terminated by SN, and the master node configuration information of the first bearer may include configuration information of release of an RLC entity corresponding to the first bearer identifier of the first bearer and configuration information of release of a logical channel corresponding to the first bearer identifier.

S1808: MN01 sends an RRC connection reconfiguration message to terminal 21.

The RRC connection reconfiguration message may include a second bearer identifier of the first bearer, primary node configuration information of the first bearer, and secondary node configuration information of the first bearer.

Optionally, the terminal 21 performs an operation of deleting and then adding the first bearer according to the bearer identifier, the primary node configuration information of the first bearer, and the secondary node configuration information of the first bearer included in the RRC connection reconfiguration message.

Optionally, the terminal 21 may execute, according to the RRC connection reconfiguration message, a deletion of the first bearer corresponding to the first bearer identifier and an addition operation of the first bearer corresponding to the second bearer identifier.

Optionally, the terminal 21 may execute, according to the RRC connection reconfiguration message, deletion of the entity corresponding to the first bearer identity and addition of the entity corresponding to the second bearer identity.

S1809: the terminal 21 sends an RRC connection reconfiguration complete message to the MN 01.

S1810: MN01 sends a SN reconfiguration complete message to SN 11.

S1811: the terminal 21 completes random access with the SN 11.

Fig. 18 takes an EN-DC scenario as an example, but the method of fig. 18 is also applicable to an nen-DC, NR-DC and NE-DC scenario, that is, the core network element 31 is 5GC, and the modification in fig. 18 when the core network element 31 is 5GC is described below.

Alternatively, in the message of fig. 18, which needs to carry the E-RAB ID, the E-RAB identity may not be carried or replaced with the first bearer identity of the first bearer.

In S1801, the first request message may be a first secondary node addition request message or a first secondary node modification request message, and the first request message may not carry the E-RAB identifier, and may carry the first bearer identifier of the first bearer in S1801.

In S1803, the first request response message may be a first secondary node addition request response message or a first secondary node modification request response message, and the E-RAB identifier may be replaced by a first bearer identifier of the first bearer, for example, the first request response message may not carry the E-RAB identifier, but carries the first bearer identifier of the first bearer.

In S1804, when the second request message is the second auxiliary node addition request message, the second request message may not carry the E-RAB identifier, and carries the first bearer identifier of the first bearer and the second bearer identifier of the first bearer in S1804; when the second request message is a second secondary node modification request message, the second secondary node modification request message may not carry the E-RAB identifier, but carries the first bearer identifier of the first bearer and the second bearer identifier of the first bearer in S1804, for example, referring to table 1, the first bearer identifier of the first bearer and the second bearer identifier of the first bearer may be carried by the information element "DRB ID" in table 1.

For example, taking the first request message in fig. 18 as a first secondary station addition request message, and taking the second request message as a second secondary station modification request message as an example, the second request message carries the first bearer identifier and the corresponding second bearer identifier information, which is used to indicate the SN11 to change the bearer identifier, that is, the second bearer identifier replaces the first bearer identifier.

Through the above scheme, when the core network 31 is 5GC, the first bearer identifier of the first bearer is used to replace the E-RAB identifier, so that the MN01 and the SN11 can know that the bearer of the second bearer identifier corresponding to the first bearer identifier, that is, the bearer identifier of the first bearer is changed.

In the method in fig. 18, the present application further provides an alternative implementation manner, the second bearer identifier of the first bearer may be carried in S1803, and does not need to carry the first bearer identifier of the first bearer, after receiving the second request message, the SN11 determines that the second request message includes the bearer identifier of the first bearer, for example, the second bearer identifier of the first bearer, and after receiving the second request message, the SN11 may generate the secondary node configuration information of the first bearer using the new bearer identifier, for example, the secondary node configuration information of the first bearer using the second bearer identifier of the first bearer.

FIG. 19 is a diagram of an embodiment of the varying PDCP SN length. Taking EN-DC as an example, in this embodiment, the first bearer terminates at MN01 before and after the bearer type is modified; in addition, the first bearer is established on MN01 and SN11 before and after the bearer type is modified.

S1901: the MN01 determines a second PDCP SN length for the first bearer.

The first bearer is terminated at MN01 before and after the bearer type modification, MN01 may determine the PDCP SN length of the first bearer after the bearer type modification, where the PDCP SN length of the first bearer after the bearer type modification is referred to as a second PDCP SN length, and the PDCP SN length of the first bearer before the bearer type modification is referred to as a first PDCP SN length.

Optionally, the length of the second PDCP SN of the first bearer may be an uplink PDCP SN length and/or a downlink PDCP SN length, and refer to the related content of the length of the second PDCP SN in S1802.

S1902: MN01 sends a secondary node modification request message to SN 11.

When the second PDCP SN length is different from the first PDCP SN length, MN01 may regenerate a bearer identification for the first bearer, where the bearer identification of the first bearer after the bearer type modification is referred to as the second bearer identification of the first bearer, and the bearer identification of the first bearer before the bearer type modification is referred to as the first bearer identification of the first bearer.

The secondary node modification request message may include the ID on the interface assigned by MN01 for terminal 21, the E-RAB ID of the first bearer and the second PDCP SN length of the first bearer.

The secondary node modification request message may also include a second bearer identification for the first bearer.

Optionally, the E-RAB ID of the first bearer may be indicated in the bearer modification list in the secondary node modification request message, and the second bearer identity of the first bearer may be indicated at the same time.

For example, the cell "DRB ID" may Be added in "E-RABs To Be Modified Item" in "SGNB Modified request" in section 9.1.4.5 of 3GPP TS36.423V15.1.0, and the specific cell structure may Be as shown in Table 1 above.

Because the bearer modification list in the secondary node modification request message does not carry the bearer identifier when the MN01 modifies the bearer configuration, the SN11 can know that the MN01 modifies the PDCP SN length of the bearer and needs to regenerate the bearer secondary node configuration information by carrying the second bearer identifier of the first bearer in the secondary node modification request message.

Next, how MN01 and SN11 generate configuration information of the first bearer is explained. MN01 and SN11 generate, for terminal 21, configuration information for release of an entity to which the first bearer identity corresponds and configuration information for addition of an entity to which the second bearer identity corresponds.

S1903: the SN11 generates secondary node configuration information for the first bearer.

After the SN11 receives the second bearer identifier of the first bearer in S1903, the first bearer identifier of the first bearer may be obtained through the E-RAB identifier of the first bearer, for example, the SN11 stores the E-RAB identifier and the corresponding first bearer identifier of the first bearer; the SN11 may then compare the first bearer id of the first bearer with the second bearer id of the first bearer, and when the first bearer id of the first bearer is different from the second bearer id of the first bearer, indicating that the MN01 has newly allocated the bearer id for the bearer, the SN11 may generate the secondary node configuration information of the first bearer.

Optionally, the secondary node configuration information of the first bearer may include configuration information of a release of the RLC entity corresponding to the first bearer identifier and configuration information of an addition of the RLC entity corresponding to the second bearer identifier. Optionally, the secondary node configuration information of the first bearer may include configuration information of release of a logical channel corresponding to the first bearer identifier and configuration information of increase of a logical channel corresponding to the second bearer identifier.

For example, the first bearer is an SCG bearer terminated by MN before the bearer type is modified, and the first bearer is an SPLIT bearer terminated by MN after the bearer type is modified, or the first bearer is an SPLIT bearer terminated by MN before the bearer type is modified, and the first bearer is an SCG bearer terminated by MN after the bearer type is modified, and the secondary node configuration information of the first bearer may include configuration information of release of an RLC entity and a logical channel corresponding to the first bearer identifier, and configuration information of increase of the RLC entity and the logical channel corresponding to the second bearer identifier.

S1904: SN11 sends a secondary node modification request response message to MN 01.

The secondary node modification request response message includes secondary node configuration information of the first bearer.

S1905: MN01 generates primary node configuration information for the first bearer.

Optionally, the primary node configuration information of the first bearer may include configuration information of a release of the PDCP entity corresponding to the first bearer identifier and configuration information of an addition of the PDCP entity corresponding to the second bearer identifier.

Optionally, the primary node configuration information of the first bearer may further include added configuration information of the RLC entity corresponding to the second bearer identifier. Optionally, the method may further include adding configuration information of the logical channel corresponding to the first bearer identifier.

Optionally, the primary node configuration information of the first bearer may further include configuration information of release of the RLC entity corresponding to the first bearer identifier, and optionally, may further include configuration information of release of the logical channel corresponding to the first bearer identifier.

For example, the first bearer is an SCG bearer terminated by the MN before the bearer type is modified, the first bearer is a SPLIT bearer terminated by the MN after the bearer type is modified, and the master node configuration information of the first bearer may include configuration information of release of a PDCP entity corresponding to the first bearer identifier, configuration information of addition of a PDCP entity corresponding to the second bearer identifier, and configuration information of addition of an RLC entity corresponding to the second bearer identifier.

For example, the first bearer is a SPLIT bearer terminated by the MN before the bearer type is modified, the first bearer is an SCG bearer terminated by the MN after the bearer type is modified, and the master node configuration information of the first bearer may include configuration information of release of a PDCP entity corresponding to the first bearer identifier, configuration information of increase of a PDCP entity corresponding to the second bearer identifier, and configuration information of release of an RLC entity corresponding to the first bearer identifier.

S1906: MN01 sends an RRC connection reconfiguration message to terminal 21.

The RRC connection reconfiguration message may include a second bearer identification of the first bearer, secondary node configuration information of the first bearer, and primary node configuration information of the first bearer.

S1907: the terminal 21 sends an RRC connection reconfiguration complete message to the MN 01.

S1908: MN01 sends a secondary node modification confirm (SN modification confirm) message to SN 11.

Fig. 19 takes an EN-DC scenario as an example, but the method of fig. 19 is also applicable to an nen-DC, NR-DC and NE-DC scenario, that is, the core network element 31 is 5GC, and the modification in fig. 19 when the core network element 31 is 5GC is described below.

Alternatively, in the message of fig. 19 that needs to carry the E-RAB ID, the E-RAB identity may be replaced by the first bearer identity of the first bearer.

In S1902, the secondary node modification request message may not carry the E-RAB identity, and may carry the first bearer identity of the first bearer. In S1903, the SN11 may determine the first bearer id of the first bearer and the second bearer id of the first bearer, and when the first bearer id of the first bearer and the second bearer id of the first bearer are different, it indicates that the MN01 newly allocates the bearer id for the bearer, and the SN11 may generate the secondary node configuration information of the first bearer.

FIG. 20 is a diagram illustrating an embodiment of changing the length of PDCP SNs, in which an EN-DC scenario is taken as an example.

S2001: the SN11 determines a second PDCP SN length for the first bearer.

The first bearer terminates at SN11, and SN11 may decide to change the PDCP SN length of the first bearer, e.g., change the PDCP length of the first bearer from the first PDCP SN length to a second PDCP SN length.

Optionally, the first PDCP SN length may be a first uplink PDCP SN length and/or a first downlink PDCP SN length, and the second PDCP SN length may be a second uplink PDCP SN length and/or a second downlink PDCP SN length. Reference may be made to fig. 18 and 19 for relevant content.

S2002: SN11 sends a secondary node modification application message to MN 01.

The secondary node modification request message includes the ID of the terminal 21 on the interface allocated by the MN01 for the terminal 21, the ID of the terminal 21 on the interface allocated by the SN11 for the terminal 21, the E-RAB ID of the first bearer, and the second PDCP SN length of the first bearer.

After receiving the secondary node modification application message, MN01 may obtain a first PDCP SN length of the first bearer through the E-RAB ID of the first bearer, and when the first PDCP SN length of the first bearer is different from the second PDCP SN length of the first bearer, MN01 may determine a second bearer identifier of the first bearer, where the second bearer identifier of the first bearer is different from the first bearer identifier of the first bearer, and the first bearer identifier of the first bearer is a bearer identifier of the first bearer before MN01 receives the secondary node modification application message, for example, MN01 may store the E-RAB ID of the first bearer and the first bearer identifier of the first bearer.

S2003: MN01 sends a secondary node modification request message to SN 11.

The secondary node modification request message may include an E-RAB identification, a second bearer identification of the first bearer.

Optionally, the E-RAB ID of the first bearer may be indicated in the bearer modification list in the second secondary node modification request message, and the second bearer identity of the first bearer may be indicated at the same time.

For example, the cell "DRB ID" can Be added To the "E-RABs To Be Modified Item" in "SGNB Modified request" in section 9.1.4.5 of 3GPP TS36.423V15.1.0, and the specific cell structure can Be as shown in Table 1 above.

S2004: the SN11 generates secondary node configuration information for the first bearer.

Optionally, the secondary node configuration information of the first bearer may include configuration information including a release of a PDCP entity corresponding to the first bearer identification of the first bearer and an addition of a PDCP entity corresponding to the second bearer identification of the first bearer.

Optionally, the secondary node configuration information of the first bearer may include configuration information of a release of an RLC entity corresponding to the first bearer identifier of the first bearer and configuration information of an increase of an RLC entity corresponding to the second bearer identifier of the first bearer, and optionally, may further include configuration information of a release of a logical channel corresponding to the first bearer identifier of the first bearer and configuration information of an increase of a logical channel corresponding to the second bearer identifier of the first bearer.

For example, the first bearer is an MCG bearer terminated by the SN before and after the change of the PDCP SN length, and the configuration information of the secondary node of the first bearer may include a release of the PDCP entity corresponding to the first bearer identifier of the first bearer and added configuration information of the PDCP entity corresponding to the second bearer identifier of the first bearer.

For example, the first bearer is a SPLIT bearer terminated by the SN before and after the change of the PDCP SN length, the configuration information of the secondary node of the first bearer may include configuration information of release of the PDCP entity and release of the RLC entity corresponding to the first bearer identifier of the first bearer, and configuration information of increase of the PDCP entity and the RLC entity corresponding to the second bearer identifier of the first bearer, and optionally, may further include configuration information of release of a logical channel corresponding to the first bearer identifier of the first bearer and configuration information of increase of a logical channel corresponding to the second bearer identifier of the first bearer

S2005: SN11 sends a secondary node modification request response message to MN 01.

The secondary node modification request response message may include secondary node configuration information for the first bearer.

S2006: MN01 generates primary node configuration information for the first bearer.

Optionally, the primary node configuration information of the first bearer may include the release of the RLC entity corresponding to the first bearer identifier of the first bearer and the added configuration information of the RLC entity corresponding to the second bearer identifier of the first bearer, and optionally, may further include the release configuration information of the logical channel corresponding to the first bearer identifier of the first bearer and the added configuration information of the logical channel corresponding to the second bearer identifier of the first bearer.

For example, the first bearer is an MCG bearer terminated by the SN or an SPLIT bearer terminated by the SN before and after the PDCP SN length change, and the master node configuration information of the first bearer may include a release of the RLC entity and an added configuration information of the RLC entity corresponding to the second bearer identifier of the first bearer, and optionally, may further include a release configuration information of a logical channel corresponding to the first bearer identifier of the first bearer and an added configuration information of a logical channel corresponding to the second bearer identifier of the first bearer.

S2007: MN01 sends an RRC connection reconfiguration message to terminal 21.

S2008: the terminal 21 sends an RRC connection reconfiguration complete message to the MN 01.

S2009: MN01 sends a secondary node modification acknowledgement message to SN 11.

Fig. 20 illustrates an EN-DC scenario, but the method in fig. 20 is also applicable to an nen-DC, NR-DC and NE-DC scenario, that is, the core network element 31 is 5GC, and the modification in fig. 20 when the core network element 31 is 5GC is described below.

In S2002, the secondary node modification application message may not carry the E-RAB ID of the first bearer, but carry the first bearer identifier of the first bearer.

In S2003, the secondary node modification request message may not carry the E-RAB ID of the first bearer, but carry the first bearer identifier of the first bearer, that is, the secondary node modification request message may carry the first bearer identifier of the first bearer and the second bearer identifier of the first bearer.

The M1 method, M2 method, fig. 18-20 present several method flow diagrams for changing the PDCP SN length, it being understood that MN01 may have functional elements corresponding to the steps of the MN01 method or flow, and SN11 may have functional elements corresponding to the steps of the SN11 method or flow.

The actions performed by MN01 in the M1 method, M2 method, methods of fig. 18-20 may be implemented by the communications apparatus provided in fig. 6a, 15 or 17; the actions performed by SN11 in the M1 method, M2 method, methods of fig. 18-20 may be implemented by the structure of SN11 provided in fig. 6b, fig. 16, or fig. 17. Reference may be made in particular to fig. 6a, 6, 15-17 for relevant content.

The M1 method, the M2 method, and the methods of fig. 18-20 may be implemented by a computer readable storage medium and a computer program product, which may be referred to in particular for the relevant contents of the computer readable storage medium and the computer program product of the embodiments of the present application.

The embodiment of the application provides a communication device, which comprises a memory and a processor, wherein the memory is used for storing a computer program, and the processor is used for calling the computer program from the memory and running the computer program, so that the communication device M1 method, the M2 method, the method executed by MN01 in figures 18-20 are realized.

The embodiment of the application provides a communication device, which comprises a memory and a processor, wherein the memory is used for storing a computer program, and the processor is used for calling the computer program from the memory and running the computer program, so that the communication device M1 method, the M2 method, and the method executed by the SN11 in the figures 18-20 are realized.

An embodiment of the present application provides a computer storage medium storing a program of the above-described M1 method, M2 method, MN01 in fig. 18 to 20, or SN11 method.

An embodiment of the present application provides a computer program product including a program that, when executed, causes the methods of the M1 method, the M2 method, MN01 in fig. 18 to 20, or SN11 described above to be performed.

The M1 method, M2 method, and methods of fig. 18-20 may be cross-referenced and incorporated with the remainder of the embodiments of the present application.

Claims

1. A method of communication in dual connectivity, the method comprising:

the method comprises the steps that a main node receives first packet data convergence protocol PDCP sequence number SN length information from an auxiliary node, wherein the first PDCP SN length information is used for indicating the first PDCP SN length of a first bearer of a PDCP anchor point on the auxiliary node;

the main node acquires the length of the first PDCP SN according to the length information of the first PDCP SN;

the primary node receiving first configuration information of the first bearer from the secondary node, the first configuration information including configuration information of a release and an addition of a PDCP entity of the first bearer;

and the main node sends the first configuration information of the first bearer to a terminal.

2. The method of claim 1, wherein the obtaining of the first PDCP SN length by the primary node comprises:

the master node reads the first PDCP SN length in the first PDCP SN length information.

3. The method of claim 1, wherein the first configuration information further comprises configuration information of a release and addition of a radio link layer control protocol, RLC, entity of the first bearer.

4. The method of claim 3, wherein the configuration information of the RLC entity release and addition comprises configuration information of the RLC entity release corresponding to the bearer identifier of the first bearer and configuration information of the RLC entity addition corresponding to the bearer identifier.

5. The method of claim 1, wherein the configuration information of the release and the addition of the PDCP entity comprises configuration information of the release of the PDCP entity corresponding to the bearer identification of the first bearer and configuration information of the addition of the PDCP entity corresponding to the bearer identification.

6. The method of claim 1, further comprising:

before receiving the first PDCP SN length information, the PDCP SN length of the first bearer is a second PDCP SN length;

when the first PDCP SN length is different from the second PDCP SN length, the main node generates second configuration information of the first bearer;

and the master node sends the second configuration information to a terminal, wherein the second configuration information of the first bearer comprises the configuration information of the release and the addition of the RLC entity of the first bearer.

7. The method of claim 6, wherein the configuration information of the release and addition of the RLC entity of the first bearer comprises configuration information of the release of the RLC entity corresponding to the bearer identification of the first bearer and configuration information of the addition of the RLC entity corresponding to the bearer identification.

8. The method of claim 6, wherein when the PDCP SN length of the first bearer is the second PDCP SN length, the PDCP of the first bearer is anchored at the master node, the method further comprising:

the master node generates the second PDCP SN length information, wherein the second PDCP SN length information is used for indicating the second PDCP SN length;

the method further comprises the following steps:

and the main node sends the second PDCP SN length information to the auxiliary node.

9. The method of claim 6, wherein when the PDCP SN length of the first bearer is the second PDCP SN length, the PDCP of the first bearer anchors at the secondary node, the method further comprising:

the primary node receives second PDCP SN length information from the secondary node, the second PDCP SN length information indicating the second PDCP SN length.

10. The method of claim 1, wherein the primary node receives first PDCP SN length information from the secondary node, comprising:

and the main node receives the first PDCP SN length information from the auxiliary node through an auxiliary node addition request response message, an auxiliary node modification request response message or an auxiliary node modification application message.

11. A method of communication in dual connectivity, the method comprising:

the auxiliary node generates the length information of a first packet data convergence protocol PDCP sequence number SN;

the auxiliary node sends the first PDCP SN length information to a main node, wherein the first PDCP SN length information is used for indicating the first PDCP SN length of a first bearer of a PDCP anchor point on the auxiliary node to the main node;

before the secondary node generates the first PDCP SN length information, the PDCP SN length of the first bearer is a second PDCP SN length, the method further comprising:

when the first PDCP SN length is different from the second PDCP SN length, the secondary node generates first configuration information of the first bearer;

the secondary node sends the first configuration information to the primary node, wherein the first configuration information comprises the configuration information of the release and the addition of the PDCP entity of the first bearer.

12. The method of claim 11, wherein the first configuration information further comprises configuration information of a release and addition of a radio link layer control protocol, RLC, entity of the first bearer.

13. The method of claim 12, wherein the configuration information of the RLC entity release and addition comprises configuration information of the RLC entity release corresponding to the bearer identification of the first bearer and configuration information of the RLC entity addition corresponding to the bearer identification.

14. The method according to any of claim 11, wherein the configuration information of the release and the addition of the PDCP entity comprises configuration information of the release of the PDCP entity corresponding to the bearer identification of the first bearer and configuration information of the addition of the PDCP entity corresponding to the bearer identification.

15. The method of claim 11, wherein when the PDCP SN length of the first bearer is the second PDCP SN length, the PDCP of the first bearer anchors at the secondary node, the method further comprising:

the secondary node generating second PDCP SN length information indicating the second PDCP SN length;

and the auxiliary node sends the second PDCP SN length information to the main node.

16. The method of claim 11, wherein when the PDCP SN length of the first bearer is the second PDCP SN length, the PDCP of the first bearer is anchored at the master node, the method comprising:

the secondary node receives second PDCP SN length information from the primary node, the second PDCP SN length information indicating the second PDCP SN length.

17. The method of claim 11 wherein the secondary node sending the first PDCP SN length information to the primary node comprises:

when the first PDCP SN length is different from the second PDCP SN length, the secondary node sends the first PDCP SN length information to the primary node.

18. The method of claim 11 wherein the secondary node sending the first PDCP SN length information to the primary node comprises:

and the auxiliary node sends the first PDCP SN length information to the main node through an auxiliary node addition request response message, an auxiliary node modification request response message or an auxiliary node modification application message.

19. A method of communication in dual connectivity, the method comprising:

a terminal receives first configuration information of a first bearer from an auxiliary node through a main node, wherein the first configuration information comprises configuration information of release and increase of a PDCP entity of the first bearer of a packet data convergence protocol PDCP anchor point on the auxiliary node; the configuration information of the release and the addition of the PDCP entity comprises configuration information of the release of the PDCP entity corresponding to the bearer identification of the first bearer and configuration information of the addition of the PDCP entity corresponding to the bearer identification;

the terminal configures the first bearer according to the first configuration information;

and the terminal is connected with the main node and the auxiliary node.

20. The method of claim 19, wherein the first configuration information further comprises configuration information for release and addition of a radio link layer control protocol, RLC, entity of the first bearer.

21. The method of claim 20, wherein the configuration information of the RLC entity release and addition comprises configuration information of the RLC entity release corresponding to the bearer identification of the first bearer and configuration information of the RLC entity addition corresponding to the bearer identification.

22. The method according to any of claims 19, wherein the terminal receives second configuration information of the first bearer from the primary node, the second configuration information comprising configuration information of a release and an addition of an RLC entity of the first bearer;

and the terminal configures the first bearer according to the second configuration information.

23. The method of claim 22, wherein the configuration information of the release and addition of the RLC entity of the first bearer included in the second configuration information includes configuration information of the release of the RLC entity corresponding to the bearer identifier of the first bearer and configuration information of the addition of the RLC entity corresponding to the bearer identifier.

24. The method according to any of the claims 19, wherein the terminal configuring the first bearer according to the first configuration information comprises:

and the terminal releases the PDCP entity of the first bearer and increases the PDCP entity of the first bearer according to the release and increased configuration information of the PDCP entity of the first bearer, wherein the PDCP SN length of the released PDCP entity is the first PDCP SN length, the PDCP SN length of the increased PDCP entity is the second PDCP SN length, and the first PDCP SN length is different from the second PDCP SN length.

25. The method of claim 24, wherein the PDCP of the first bearer is anchored at the primary node when the PDCP length of the first bearer is the first PDCP SN length, and wherein the PDCP of the first bearer is anchored at the secondary node when the PDCP length of the first bearer is the second PDCP SN length.

26. A communication device, characterized in that the communication device comprises means for performing the steps of the method of any of claims 1-10, respectively.

27. A communication device, characterized in that the communication device comprises means for performing the steps of the method of any of claims 11-18, respectively.

28. A communication device, characterized in that it comprises means for performing the steps of the method of any of claims 19-25, respectively.

29. A communications apparatus comprising a processor coupled to a memory, the memory storing a computer program, the processor being configured to execute the computer program in the memory to cause a network device to perform the method of any of claims 1 to 10.

30. A communications apparatus comprising a processor coupled to a memory, the memory storing a computer program, the processor being configured to execute the computer program in the memory to cause a network device to perform the method of any of claims 11 to 18.

31. A communications apparatus comprising a processor coupled to a memory, the memory storing a computer program, the processor being configured to execute the computer program in the memory to cause a terminal to perform the method of any of claims 19 to 25.

32. A computer-readable storage medium for storing a computer program which, when executed by a processor, performs the steps of the method of any one of claims 1-25.

33. A communication system comprising the primary node performing the method of any of claims 1-10 and the secondary node performing the method of any of claims 11-18.