WO2022198597A1

WO2022198597A1 - Data transmission method and apparatus in cell reselection scenario, and device and storage medium

Info

Publication number: WO2022198597A1
Application number: PCT/CN2021/083097
Authority: WO
Inventors: 林雪; 王淑坤
Original assignee: Oppo广东移动通信有限公司
Priority date: 2021-03-25
Filing date: 2021-03-25
Publication date: 2022-09-29
Also published as: CN116636255A

Abstract

The present application relates to the field of wireless communications, and discloses a data transmission method and apparatus in a cell reselection scenario, and a device and a storage medium. The method is applied to a target base station, and comprises: receiving uplink inactive data sent by a terminal; and by means of a first interface, sending the uplink inactive data to a source base station, UE context of the terminal being retained on the source base station side, and the first interface being a communication interface between the target base station and the source base station, wherein the uplink inactive data is uplink data transmitted by the terminal by means of an SDT process, and the SDT process is an RA-SDT process. According to the solutions of the embodiments of the present application, RA-SDT in a cell reselection scenario can be implemented.

Description

Data transmission method, device, device and storage medium in cell reselection scenario

technical field

The present application relates to the field of wireless communication, and in particular, to a data transmission method, apparatus, device and storage medium in a cell reselection scenario.

Background technique

Small data transmission (Small Data Transmission, SDT) was introduced in R17, and the small data transmission process is an inactive data transmission process.

The small data transmission may be a random access (Random Access, RA)-based small data transmission (ie, RA-SDT). For the RA-SDT in the cell reselection scenario, how to realize data transmission, the related art has not yet provided a better solution.

SUMMARY OF THE INVENTION

The embodiments of the present application provide a data transmission method, apparatus, device, and storage medium in a cell reselection scenario, which can implement RA-SDT in the cell reselection scenario. The technical solution is as follows:

According to an aspect of the present application, a data transmission method in a cell reselection scenario is provided, which is applied to a target base station, and the method includes:

Receive uplink inactive data sent by the terminal;

The uplink inactive data is sent to the source base station through the first interface, the UE context of the terminal is retained on the source base station side, and the first interface is the communication between the target base station and the source base station interface;

Wherein, the uplink inactive state data is uplink data transmitted by the terminal through an SDT process, and the SDT process is an RA-SDT process.

According to an aspect of the present application, a data transmission method in a cell reselection scenario is provided, which is applied to a source base station, and the UE context of a terminal is retained on the source base station side, and the method includes:

receiving, through a first interface, uplink inactive data sent by a target base station, where the first interface is a communication interface between the target base station and the source base station;

sending the uplink inactive state data to the core network;

According to an aspect of the present application, a target device in a cell reselection scenario is provided, the device comprising: an uplink receiving module and an uplink sending module;

The uplink receiving module is used for receiving uplink inactive data sent by the terminal;

The uplink sending module is configured to send the uplink inactive state data to the source device through a first interface, the UE context of the terminal is retained on the source base station side, and the first interface is between the target device and the source device. a communication interface between the source devices;

According to an aspect of the present application, a source device in a cell reselection scenario is provided, the UE context of the terminal is retained on the source device side, and the device includes: an uplink receiving module and an uplink sending module;

The uplink receiving module is configured to receive uplink inactive data sent by the target device through a first interface, where the first interface is a communication interface between the target device and the source device;

The uplink sending module is configured to send the uplink inactive state data to the core network;

According to an aspect of the present application, a network device is provided, the network device comprising: a transceiver; wherein,

the transceiver, configured to receive uplink inactive data sent by the terminal;

The transceiver is configured to send the uplink inactive data to the source base station through a first interface, the UE context of the terminal is retained on the source base station side, and the first interface is the connection between the network device and the source base station. the communication interface between the source base stations;

the transceiver, configured to receive uplink inactive data sent by a target base station through a first interface, where the first interface is a communication interface between the network device and the target base station;

the transceiver, configured to send the uplink inactive state data to the core network;

The uplink inactive data is uplink data transmitted by the terminal through an SDT process, the SDT process is an RA-SDT process, and the UE context of the terminal is retained on the network device side.

According to an aspect of the present application, a computer-readable storage medium is provided, and executable instructions are stored in the readable storage medium, and the executable instructions are loaded and executed by a processor to implement the cell reconfiguration according to the above aspect. Select the data transfer method in the scenario.

According to an aspect of the embodiments of the present application, a chip is provided, the chip includes a programmable logic circuit and/or program instructions, and when the chip runs on a computer device, the chip is used to implement the cell reset described in the above aspect. Select the data transfer method in the scenario.

According to an aspect of the present application, a computer program product is provided, which, when running on a processor of a computer device, enables the computer device to execute the data transmission method in the cell reselection scenario described in the above aspect.

The technical solutions provided by the embodiments of the present application include at least the following beneficial effects:

For the small data transmission process in the cell reselection scenario, the UE context of the terminal can be retained on the source base station side, then when the target base station receives uplink inactive data, the target base station sends uplink data to the source base station through the first interface For inactive data, the source base station transmits uplink inactive data upward, so as to realize RA-SDT in the cell reselection scenario.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present application more clearly, the following briefly introduces the drawings that are used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a flowchart of an EDT data transmission process provided by an exemplary embodiment of the present application;

2 is a flowchart of an EDT data transmission process in a cell reselection scenario provided by an exemplary embodiment of the present application;

3 is a flowchart of an RNAU process for performing UE context migration provided by an exemplary embodiment of the present application;

4 is a flowchart of an RNAU process without performing UE context migration provided by an exemplary embodiment of the present application;

FIG. 5 is a flowchart of a handover preparation stage provided by an exemplary embodiment of the present application;

6 is a block diagram of a communication system provided by an exemplary embodiment of the present application;

7 is a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application;

8 is a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application;

9 is a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application;

10 is a schematic diagram of a mapping relationship between a GTP tunnel and a logical channel index provided by an exemplary embodiment of the present application;

11 is a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application;

12 is a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application;

13 is a structural block diagram of a target device in a cell reselection scenario provided by an exemplary embodiment of the present application;

14 is a structural block diagram of a source device in a cell reselection scenario provided by an exemplary embodiment of the present application;

FIG. 15 is a schematic structural diagram of a network device provided by an exemplary embodiment of the present application.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

First, briefly introduce the terms involved in the embodiments of the present application:

Early Data Transmission (EDT):

In Long Term Evolution (Long Term Evolution, LTE), an EDT process is introduced, which can be understood as a small data transmission process. During this process, the terminal may always remain in an idle state (RRC_IDLE), a suspended state (RRC_SUSPEND), or an inactive state (RRC_INACTIVE) to complete the transmission of uplink and/or downlink small data packets. In the configuration, the network will configure a maximum transmission block threshold (TB size) that the current network allows transmission on the System Information Block 2 (System Information Block 2, SIB2), and the terminal determines the amount of data to be transmitted. Maximum TB size, the terminal can initiate EDT transmission; otherwise, the terminal uses the normal connection establishment process to enter the connection state to transmit data.

If the cell where the terminal initiates the uplink EDT is the same as the last serving cell, the base station can directly submit the uplink data to the core network after receiving the RRC connection recovery request and uplink data sent by the terminal. The specific process is shown in Figure 1.

If the cell where the terminal initiates the uplink EDT is different from the last serving cell, after receiving the radio resource control (RRC Resource Control, RRC) connection recovery request and uplink data sent by the terminal, the target base station will use the RRC connection recovery request. The active wireless network temporary identifier (Inactive-Radio Network Temporary Identity, I-RNTI) finds the source base station, and asks the source base station for the UE context by requesting the UE context request (Retrieve UE Context Request); the source base station receives the request from the target base station. After the UE context is requested, the UE context is migrated to the target base station, and the target base station submits the user data to the core network. The specific process is shown in FIG. 2 .

RAN-based Notification Area Update (RNAU):

Before the terminal enters the RRC_INACTIVE state, the last serving cell (last serving cell) can configure a RAN-based Notification Area (RNA) for the terminal, and the RNA includes one or more cells in the core registration area. In order to help the network understand the current location information of the terminal, when the terminal moves within the RNA range, a periodic RNA update process needs to be performed; when the terminal moves outside the RNA, the RNA update process also needs to be performed to notify the network where the RNA is currently located.

The terminal performs the RNA update procedure by initiating RRC recovery in the current cell. If the terminal undergoes cell reselection, that is, moves to a cell other than the last serving cell, the target cell needs to find the source base station according to the I-RNTI, and ask the source base station for the UE context.

In order to avoid frequent UE context migration, the source base station may choose to perform UE context migration, or may choose to save the UE context on the source side.

With reference to Figure 3, the terminal initiates RRC recovery to perform the RNA update process, and the source base station migrates the UE context to the target base station; with reference to Figure 4, the terminal initiates RRC recovery to perform the RNA update process, and the source base station saves the UE context on the source side, Feedback to the target base station the failure to obtain the UE context.

Small data transmission (Small Data Transmission, SDT):

In the 5G NR system, there are three RRC states: RRC_IDLE (idle state), RRC_INACTIVE (inactive state), and RRC_CONNECTED (connected state).

Among them, the RRC_INACTIVE state is a new state introduced by the 5G system from the perspective of energy saving. For a terminal in the RRC_INACTIVE state, the radio bearer and all radio resources will be released, but the terminal side and the base station side retain the UE access context to quickly restore the RRC connection. The network usually keeps the terminal in the RRC_INACTIVE state with infrequent data transmission.

Before R16, the terminal in the RRC_INACTIVE state did not support data transmission. When the uplink or downlink data arrives, the terminal needs to restore the connection and release it to the inactive state after the data transmission is completed. For a terminal with a small amount of data and a low transmission frequency, such a transmission mechanism will lead to unnecessary power consumption and signaling overhead. Therefore, R17 established a project to carry out research on small data transmission under RRC_INACTIVE. The project objectives mainly have two directions: small data transmission based on random access (two-step/four-step) (ie RA-SDT) and pre-configured resources (such as Small data transfer of CG type1).

RA-SDT supports mobility. When the terminal performs cell reselection, the terminal can initiate a RA-SDT-based procedure according to the configuration of the currently camping cell. According to the conclusion of the RAN2#111e meeting, for RA-SDT in the cell reselection scenario, the UE context can be migrated from the source base station to the target base station, or can be retained in the source base station.

In addition, according to the research progress of the positioning (positioning) topic, it is necessary to support the transmission of the positioning measurement report (positioning measurement report) in the inactive state, and the positioning measurement report needs to be carried in the non-access stratum (Non-Access Stratum, NAS) message, And realize air interface transmission through Signal Resource Bearer (SRB). After further discussion in RAN2#113e, the SDT process needs to support the transmission of SRB1/SRB2 data in addition to supporting the data transmission of the data radio bearer (DRB).

Data transmission between Xn interfaces in switching scenarios:

In the handover process, in order to avoid user data loss, a General Packet Radio Service Tunneling Protocol (GTP) tunnel needs to be established between the target base station and the source base station in the handover preparation stage to support user data between the two nodes. transmission.

The source base station sends a handover request (Handover Request) to the target base station, including UE Context Information (UE Context Information) and PDU Session Resource Setup List (PDU Session Resource Setup List), etc., which are used by the target base station for each PDU session. GTP tunnel. The target base station feeds back the establishment of the GTP tunnel to the source base station through Handover Request Acknowledge. The specific process is shown in Figure 5.

For the RA-SDT process in which cell reselection occurs, the source base station can keep the UE context on the source side (that is, SDT without anchor relocation scenario). Under this scheme, the target base station needs to transfer the received uplink data through the Xn interface. To the source base station, the source base station completes the upward submission of uplink data, such as: submit the user plane data to the user plane function (User Plane Function, UPF), and submit the control plane data to the access and mobility management function (Access and Mobility Management). Function, AMF). The implementation of the above scheme has the following problems:

For the transmission of DRB data between Xn interfaces, the GTP tunnel in the current protocol is established for each PDU session, and the data transmitted between the interfaces is in the form of Service Data Adaptation Profile (SDAP) Service Data Unit (Service Data). Unit, SDU) or Packet Data Convergence Protocol (PDCP) protocol data unit (Protocol Data Unit, PDU), which requires nodes on both sides to share UE context information, including radio link control (Radio Link Control, RLC) configuration, PDCP configuration, etc. For the SDT without anchor relocation scenario, the target base station cannot obtain the PDCP configuration, so the data cannot be processed by the PDCP and above protocol layers, so the existing data transmission method between Xn interfaces cannot be used in the SDT without anchor relocation solution.

For the transmission of SRB data between Xn interfaces, the current protocol defines two scenarios for transmitting PDCP-C PDUs through Xn interfaces, namely:

- Scenario 1: For the RNAU process that does not perform UE context migration, the source base station encapsulates the RRC release message in the PDCP-C PDU container (container). MAC) layer is processed and transmitted to the terminal.

- Scenario 2: For the split SRB in the dual link scenario, the secondary node (Secondary Node, SN) needs to encapsulate the RRC message into the PDCP-C PDU container and transfer it to the master node (Master Node, MN), and the PDCP layer on the MN side needs to encapsulate the RRC message. Process the data.

Therefore, the current application scenario does not support the transmission of SRB data when SDT without anchor relocation.

In the related art, there is no support for transmitting DRB data and SRB data in the RA-SDT process in the cell reselection scenario. Based on the above problems, the present application provides the following solutions.

FIG. 6 shows a block diagram of a communication system provided by an exemplary embodiment of the present application. The communication system may include: an access network 12 and a terminal 14 .

The access network 12 includes several network devices 120 . The network device 120 may be a base station, which is a device deployed in an access network to provide a wireless communication function for a terminal. The base station may include various forms of macro base station, micro base station, relay station, access point and so on. In systems using different radio access technologies, the names of devices with base station functions may be different. For example, in LTE systems, they are called eNodeBs or eNBs; in 5G NR-U systems, they are called gNodeBs or gNBs. . As communication technology evolves, the description of "base station" may change. For the convenience of the embodiments of the present application, the above-mentioned apparatuses that provide the terminal 14 with a wireless communication function are collectively referred to as network equipment. Optionally, the communication interface between the network devices 120 is an Xn interface.

The terminal 14 may include various handheld devices, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to wireless modems with wireless communication functions, as well as various forms of user equipment, mobile stations (Mobile Station, MS), Terminal (terminal device) and so on. For the convenience of description, the devices mentioned above are collectively referred to as terminals. The network device 120 and the terminal 14 communicate with each other through some air interface technology, such as a Uu interface. Optionally, the terminal 14 supports performing the small data transmission process in the inactive state.

The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Global System of Mobile Communication (GSM) system, Code Division Multiple Access (CDMA) system, wideband Code Division Multiple Access (CDMA) system (Wideband Code Division Multiple Access, WCDMA) system, General Packet Radio Service (General Packet Radio Service, GPRS), Long Term Evolution (Long Term Evolution, LTE) system, LTE Frequency Division Duplex (Frequency Division Duplex, FDD) system, LTE Time Division Duplex (TDD) systems, Advanced Long Term Evolution (LTE-A) systems, New Radio (NR) systems, evolution systems of NR systems, LTE on unlicensed frequency bands (LTE-based access to Unlicensed spectrum, LTE-U) system, NR-U system, Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) communication system, Wireless Local Area Networks (WLAN), Wireless Fidelity (WiFi), next-generation communication systems or other communication systems, etc.

Generally speaking, traditional communication systems support a limited number of connections and are easy to implement. However, with the development of communication technology, mobile communication systems will not only support traditional communication, but also support, for example, Device to Device (Device to Device, D2D) communication, Machine to Machine (M2M) communication, Machine Type Communication (MTC), Vehicle to Vehicle (V2V) communication and Vehicle to Everything (V2X) system, etc. The embodiments of the present application can also be applied to these communication systems.

FIG. 7 shows a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application. The method can be applied to the communication system as shown in FIG. 6, and the method includes:

Step 701, the terminal sends uplink inactive data.

In a possible implementation manner, the terminal sends uplink inactive data by initiating an SDT process.

SDT is a data transmission method configured for a terminal in an inactive state. SDT does not require the establishment of an RRC connection between the terminal device and the network device. For a terminal device with a small amount of data and a low transmission frequency, if the RRC connection with the network device can only be restored through the connection establishment and recovery process, the data transmission can be performed after the RRC connection with the network device is restored. After the data transmission is completed, it needs to return to the inactive state. , the power consumption of the terminal is relatively large. By performing the SDT process, the terminal can avoid the transition of the connection state, thereby reducing the power consumption of the terminal.

Optionally, the SDT process includes: a small data transmission process based on a configuration grant (Configured Grant, CG); or a small data transmission process based on random access. The small data transmission process based on random access may be a small data transmission process based on 2-step random access, or a small data transmission process based on 4-step random access. In the embodiment of the present application, the uplink inactive data is uplink data transmitted by the terminal through the SDT process, and the SDT process is a small data transmission process based on random access.

Optionally, the type of uplink inactive data includes at least one of the following types: DRB data; SRB data.

Step 702: The target base station receives the uplink inactive data sent by the terminal.

In the embodiment of the present application, the terminal is in a cell reselection scenario, the last serving base station of the terminal is the source base station, and the serving base station after cell reselection is the target base station. Since the terminal has been reselected to the target base station, the target base station receives the uplink inactive data sent by the terminal.

Step 703: Through the first interface, the target base station sends uplink inactive data to the source base station, and the UE context of the terminal is retained on the source base station side.

The first interface is a communication interface between the target base station and the source base station. Optionally, the first interface is an Xn interface.

In a possible implementation manner, since the UE context of the terminal remains on the source base station side, the target base station needs to transfer the received uplink inactive state data to the source base station through the first interface, and the source base station completes the uplink inactive state. Upward submission of data.

Optionally, step 703 is implemented as: establishing a GTP tunnel for data transmission between the first interfaces for the logical channel supporting the SDT process, and through the GTP tunnel between the first interfaces, the target base station sends uplink inactive data to the source base station.

Optionally, step 703 is implemented as: through the RRC container in the request for obtaining the UE context between the first interfaces, the target base station sends uplink inactive data to the source base station.

Optionally, step 703 is implemented as: through the RRC container in the XnAP signaling between the first interfaces, the target base station sends uplink inactive data to the source base station.

Step 704, the source base station receives uplink inactive data.

In a possible implementation manner, the source base station correspondingly receives uplink inactive data sent by the target base station to the source base station through the first interface.

Step 705, the source base station sends uplink inactive data to the core network.

In a possible implementation manner, after receiving the uplink inactive state data, the source base station further submits the uplink inactive state data to the core network. Exemplarily, the source base station submits the uplink inactive data belonging to the user plane data to the UPF; and submits the uplink inactive data belonging to the control plane data to the AMF.

To sum up, in the method provided in this embodiment, for the small data transmission process in the cell reselection scenario, the UE context of the terminal can be retained on the source base station side, and when the target base station receives uplink inactive data, The target base station sends the uplink inactive state data to the source base station through the first interface, and the source base station transmits the uplink inactive state data upward, so as to realize the RA-SDT in the cell reselection scenario.

In the optional embodiment based on FIG. 7 , in order to transmit inactive data between the target base station and the source base station through the first interface, the present application provides the following three solutions.

Option One:

In an exemplary embodiment, a GTP tunnel for data transmission between the first interfaces is established for the logical channel supporting the SDT process, and uplink inactive data or downlink inactive data is transmitted through the GTP tunnel between the first interfaces.

FIG. 8 shows a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application. The method can be applied to the communication system as shown in FIG. 6, and the method includes:

Step 801, the terminal sends uplink inactive data.

For the implementation manner of this step, refer to the above-mentioned step 701, which will not be repeated here.

Step 802, the target base station receives the uplink inactive data sent by the terminal.

For the implementation manner of this step, refer to the foregoing step 702, which will not be repeated here.

Step 803, the source base station sends the first GTP tunnel information to the target base station, where the first GTP tunnel information is used to indicate the first GTP tunnel between the first interfaces.

The first GTP tunnel is a GTP tunnel established between the first interface for transmitting uplink inactive data between the target base station and the source base station.

Step 804, the target base station receives the first GTP tunnel information.

Optionally, the first GTP tunnel information is at least one of the following information: a first network protocol (Internet Protocol, IP) address; a first GTP tunnel endpoint identifier (Tunnel Endpoint IDentifier, TEID).

In a possible implementation manner, the first GTP tunnel information is carried in a second message, and the second message is used to provide the target base station with the first interface established by the source base station for the logical channel supporting the transmission of inactive data. information about the first GTP tunnel.

Exemplarily, with reference to FIG. 9 , the process of acquiring the first GTP tunnel information by the target base station through the second message is shown in steps 903 to 906 as follows:

Step 903, the target base station sends a first message to the source base station, where the first message is used to ask the source base station for the UE context of the terminal, and is used to inform the source base station that the terminal is performing an RA-SDT process.

Exemplarily, the first message is a request for a UE context (Retrieve UE Context Request).

In a possible implementation manner, step 903 is replaced by:

S11, the terminal sends the I-RNTI to the target base station.

Optionally, the I-RNTI is carried in the RRC connection recovery request message. That is, the terminal sends an RRC connection restoration request message to the target base station, and the RRC connection restoration request message includes the I-RNTI.

S12, the target base station receives the I-RNTI.

Optionally, the target base station receives the I-RNTI by receiving the RRC connection recovery request message.

S13, the target base station addresses the source base station based on the I-RNTI, and sends a first message to the source base station.

Step 904, the source base station receives the first message.

Optionally, the first message carries at least one of the following information: a first UE XnAP identifier; a first UE context identifier; a first recovery MAC-I; a first target cell identifier.

Step 905, the source base station sends a second message to the target base station, where the second message includes the first GTP tunnel information.

Step 906, the target base station receives the second message.

As shown in the above steps 903 to 906, the target base station sends a first message to the source base station, asking for the UE context of the terminal, and informs the terminal that the RA-SDT process is being performed, and the source base station does not execute the UE after receiving the first message. Context migration, in order to ensure the progress of the RA-SDT process, the source base station sends a second message to the target base station, the second message includes the first GTP tunnel information, and the first GTP tunnel information is used to establish the first GTP tunnel between the first interfaces, Then, the target base station can subsequently send uplink inactive data through the first GTP tunnel of the first interface to ensure the RA-SDT process.

Optionally, the second message further includes: a first logical channel index. The first logical channel index is used to indicate the logical channel corresponding to the first GTP tunnel. Optionally, the first logical channel index is determined by the source base station based on the UE context of the terminal reserved at the source base station side.

Optionally, the first GTP tunnel information and the first logical channel index correspond to a first mapping relationship; the target base station stores the first mapping relationship in response to receiving the second message.

Exemplarily, with reference to FIG. 10 , the GTP tunnel established between the source base station and the target base station has a mapping relationship with a logical channel identity (LCID), such as: LCID#1 corresponds to GTP tunnel#1; LCID#2 Corresponds to GTP tunnel #2; LCID #3 corresponds to GTP tunnel #3.

Optionally, the second message further includes: terminal-specific RLC configuration information. Optionally, the terminal-specific RLC configuration information is determined by the source base station based on the UE context of the terminal reserved at the source base station side. By acquiring the terminal-specific RLC configuration information, the target base station can ensure that the data is processed by the high-level protocol layer.

Step 805: The target base station sends uplink inactive data to the source base station through the first GTP tunnel between the first interfaces.

In a possible implementation manner, step 805 is replaced by:

S21, the target base station determines the logical channel corresponding to the uplink inactive data.

S22, the target base station transmits the PDCP PDU or RLC PDU of uplink inactive data to the source base station through the first GTP tunnel corresponding to the logical channel between the first interfaces.

Exemplarily, with reference to FIG. 10, the target base station determines that the logical channel corresponding to the uplink inactive data is LCID#1, and the first GTP tunnel corresponding to LCID#1 is the GTP tunnel #1, then the GTP between the first interfaces Tunnel #1, the target base station transmits the PDCP PDU or RLC PDU of uplink inactive data to the source base station.

Step 806, the source base station receives uplink inactive data.

In a possible implementation manner, the source base station receives the PDCP PDU or RLC PDU of the uplink inactive data sent by the target base station through the first GTP tunnel corresponding to the logical channel of the uplink inactive data between the first interfaces.

Step 807, the source base station sends uplink inactive data to the core network.

Correspondingly, the core network receives uplink inactive data.

Step 808, the core network sends downlink inactive data.

The downlink inactive data is the downlink data sent by the core network through the SDT process initiated by the terminal, and the SDT process is a small data transmission process based on random access.

In a possible implementation manner, the core network receives uplink inactive data sent by the source base station, and sends downlink inactive data to the source base station in order to feed back the uplink inactive data.

Step 809, the source base station receives downlink inactive data.

Step 810, the target base station sends the second GTP tunnel information to the source base station, where the second GTP tunnel message is used to indicate the second GTP tunnel between the first interfaces.

The second GTP tunnel is a GTP tunnel established between the first interface for transmitting downlink inactive data between the target base station and the source base station.

Step 811, the source base station receives the second GTP tunnel information.

Optionally, the second GTP tunnel information includes: a second IP address; and a second GTP TEID.

In a possible implementation manner, the second GTP tunnel information is carried in a third message, and the third message is used to provide the source base station with the first interface established by the target base station for the logical channel supporting the transmission of inactive data. information about the second GTP tunnel.

Exemplarily, with reference to FIG. 9 , the process for the source base station to obtain the second GTP tunnel information through the third message is shown in steps 912 to 913 as follows:

Step 912, the target base station sends a third message to the source base station, where the third message includes the second GTP tunnel information.

In a possible implementation manner, step 912 is alternatively implemented as:

S31, the source base station sends a fourth message to the target base station, where the fourth message is used to inform the target base station that downlink inactive data arrives at the source base station.

S32, the target base station receives the fourth message.

S33, after receiving the fourth message sent by the source base station, the target base station sends a third message to the source base station.

Optionally, the fourth message includes logical channel indication information, where the logical channel indication information is used to indicate the logical channel on which the second GTP tunnel needs to be established. That is, the target base station determines, through the fourth message, the logical channel on which the second GTP tunnel needs to be established.

In another possible implementation manner, step 912 is alternatively implemented as: after receiving the second message sent by the source base station, the target base station sends a third message to the source base station. In this implementation, steps 912 to 913 may be implemented before step 911 . That is, a second GTP tunnel for downlink inactive data transmission is first established between the target base station and the source base station, and then when downlink inactive data arrives, the second GTP tunnel is used for data transmission.

Optionally, the second message includes a first logical channel index, where the first logical channel index is used to indicate a logical channel on which the second GTP tunnel needs to be established. That is, the target base station determines the logical channel for which the second GTP tunnel needs to be established through the second message sent by the source base station. Since the second message is used to establish the first GTP tunnel between the first interfaces for some logical channels, the target base station is based on the The index of the first logical channel in the second message also correspondingly establishes a second GTP tunnel for the above-mentioned logical channel through the third message.

Step 913, the source base station receives the third message.

Optionally, the third message further includes: a second logical channel index. The second logical channel index is used to indicate the logical channel corresponding to the second GTP tunnel. Optionally, the second logical channel index in the third message is determined based on the foregoing fourth message or the foregoing second message.

Optionally, the second GTP tunnel information and the second logical channel index correspond to a second mapping relationship; the source base station stores the second mapping relationship in response to receiving the third message.

Step 812: The source base station sends downlink inactive data to the target base station through the second GTP tunnel between the first interfaces.

In a possible implementation, step 812 is replaced by:

S41, the source base station determines the logical channel corresponding to the downlink inactive data.

S42, the source base station transmits the PDCP PDU or RLC PDU of the downlink inactive data to the target base station through the second GTP tunnel corresponding to the logical channel between the first interfaces.

Step 813, the target base station receives downlink inactive data.

In a possible implementation manner, the target base station receives the PDCP PDU or RLC PDU of the downlink inactive data sent by the source base station through the second GTP tunnel corresponding to the logical channel of the downlink inactive data between the first interfaces.

Step 814, the target base station sends downlink inactive data to the terminal.

Correspondingly, the terminal receives downlink inactive data.

Optionally, in this embodiment, the inactive data includes at least one of the following types: DRB data; SRB data. That is, the uplink inactive state data and the downlink inactive state data may both be DRB data or both may be SRB data.

To sum up, in the method provided in this embodiment, for the small data transmission process of DRB data or SRB data in the cell reselection scenario, the UE context of the terminal can be retained on the source base station side, and the logical channel supporting the SDT process is established. The GTP tunnel for data transmission between the first interfaces transmits uplink inactive data or downlink inactive data through the GTP tunnel between the first interfaces.

Option II:

In an exemplary embodiment, the uplink inactive data includes the first uplink SRB data, and the first uplink SRB data is transmitted through the RRC container in the request for obtaining the UE context between the first interfaces.

FIG. 11 shows a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application. The method can be applied in the communication system as shown in Figure 6, and the method includes:

Step 1101, the terminal sends the first uplink SRB data.

In a possible implementation manner, the terminal sends the first uplink SRB data by initiating an SDT process.

Optionally, the first uplink SRB data is uplink SRB data that has not undergone RLC segmentation and adopts a default RLC configuration.

Step 1102, the target base station receives the first uplink SRB data sent by the terminal.

Optionally, before step 1102, the target base station receives a first data indication message sent by the terminal, where the first data indication message is used to indicate that uplink SRB data exists in the RA-SDT process. Optionally, the first data indication message includes at least one of the following messages: a resume cause (Resume Cause); and a MAC control element (Control Element, CE).

Step 1103, through the first interface, the target base station sends a fifth message to the source base station, the fifth message is used to request the UE context of the terminal from the source base station, and is used to inform the source base station that the terminal is in the RA-SDT process, and the fifth message is used to request the source base station for the UE context of the terminal. The RRC container in the message is used to transmit the PDCP-C PDU encapsulated with the first uplink SRB data.

Exemplarily, the fifth message is a request for UE context (Retrieve UE Context Request).

In a possible implementation manner, step 1103 is replaced by:

S51, the terminal sends the I-RNTI to the target base station.

S52, the target base station receives the I-RNTI.

S53, the target base station addresses the source base station based on the I-RNTI, and sends a fifth message to the source base station.

Step 1104, the source base station receives the fifth message.

In a possible implementation manner, the source base station receives the first uplink SRB data through the RRC container in the fifth message.

Optionally, the fifth message includes at least one of the following information: a second UE XnAP identity; a second UE context identity; a second recovery MAC-I; and a second target cell identity.

Optionally, the second UE XnAP identifier in the fifth message is used for the target base station to provide the source base station with a first XnAP signaling transmission channel for transmitting downlink SRB data. In the presence of downlink SRB data, the following steps 1106 to 1110 will be performed.

Step 1105, the source base station sends the first uplink SRB data to the core network.

Correspondingly, the core network receives the first uplink SRB data.

Step 1106, the core network sends the first downlink SRB data.

In a possible implementation manner, the core network receives the first uplink SRB data sent by the source base station, and sends the first downlink SRB data to the source base station in order to feedback the first uplink SRB data.

Step 1107, the source base station receives the first downlink SRB data.

Step 1108, through the first XnAP signaling transmission channel between the first interfaces, the source base station sends the first XnAP signaling to the target base station, and the RRC container in the first XnAP signaling is used to transmit the first downlink SRB data encapsulated in the RRC container. PDCP-C PDU.

Wherein, the first XnAP signaling transmission channel is established by the target base station based on the second UE XnAP identifier.

Optionally, the first XnAP signaling includes at least one of the following signaling: RRC transfer (RRC TRANSFER); dedicated XnAP signaling, where the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process. That is, the first XnAP signaling may be RRC transfer extended for this scenario, or may be dedicated XnAP signaling introduced for this scenario.

Step 1109, the target base station receives the first XnAP signaling.

In a possible implementation manner, the target base station receives the first downlink SRB data through the RRC container in the first XnAP signaling.

Step 1110, the target base station sends the first downlink SRB data to the terminal.

Correspondingly, the terminal receives the first downlink SRB data.

To sum up, the method provided in this embodiment is aimed at the small data transmission process triggered by the first uplink SRB data in the cell reselection scenario. For SRB data, the UE context of the terminal can be retained on the source base station side, and the target base station transmits the first uplink SRB data through the RRC container in the request for obtaining the UE context between the first interfaces.

At the same time, since the request for obtaining the UE context sent by the target base station includes the UE XnAP identifier, the XnAP signaling transmission channel can be established through the UE XnAP identifier to realize the transmission of the first downlink SRB data.

third solution:

In an exemplary embodiment, the uplink inactive state data includes the second uplink SRB data, and the second uplink SRB data is transmitted through the RRC container in the XnAP signaling between the first interfaces.

FIG. 12 shows a flowchart of a data transmission method in a cell reselection scenario provided by an exemplary embodiment of the present application. The method can be applied in the communication system as shown in Figure 6, and the method includes:

Step 1201, the terminal sends the second uplink SRB data.

In a possible implementation manner, the terminal sends the second uplink SRB data by initiating an SDT process.

Optionally, the second uplink SRB data is uplink SRB data that adopts a default RLC configuration or adopts a terminal-specific RLC configuration.

Step 1202, the target base station receives the second uplink SRB data sent by the terminal.

Optionally, before step 1202, the target base station receives a second data indication message sent by the terminal, where the second data indication message is used to indicate that uplink SRB data exists in the RA-SDT process. Optionally, the second data indication message includes at least one of the following messages: Resume Cause; MAC CE.

Step 1203, the source base station sends a third UE XnAP identifier to the target base station, where the third UE XnAP identifier is used to indicate the second XnAP signaling transmission channel between the first interfaces.

In a possible implementation manner, step 1203 is replaced by:

S61, through the first interface, the target base station sends a sixth message to the source base station, where the sixth message is used to ask the source base station for the UE context, and is used to inform the source base station that the terminal is performing the RA-SDT process.

Exemplarily, the sixth message is a request for a UE context (Retrieve UE Context Request).

Optionally, the target base station addresses the source base station based on the I-RNTI sent by the terminal, and sends a sixth message to the source base station.

S62, the source base station receives the sixth message.

Optionally, the sixth message includes a fourth UE XnAP identifier, and the fourth UE XnAP identifier is used to indicate a third XnAP signaling transmission channel for transmitting downlink SRB data.

S63, the source base station sends the third UE XnAP identifier to the target base station.

As shown in the above steps S61 to S63, the target base station sends a sixth message to the source base station, asking for the UE context of the terminal, and informs the terminal that the RA-SDT process is being performed, and the source base station does not execute the UE after receiving the sixth message. Context migration, in order to ensure the progress of the RA-SDT process, the source base station sends a third UE XnAP identifier to the target base station, and the third UE XnAP identifier is used to indicate the second XnAP signaling transmission channel between the first interfaces, then the target base station can follow up The second uplink SRB data is transmitted through the second XnAP signaling transmission channel of the first interface to ensure the RA-SDT process.

Step 1204, the target base station receives the third UE XnAP identifier.

Step 1205, through the second XnAP signaling transmission channel between the first interfaces, the target base station sends the second XnAP signaling to the source base station, and the RRC container in the second XnAP signaling is used to transmit the PDCP encapsulated with the second uplink SRB data -C PDUs.

Wherein, the second XnAP signaling transmission channel is established by the source base station based on the XnAP identifier of the third UE.

Optionally, the second XnAP signaling includes at least one of the following signaling: RRC transfer (RRC TRANSFER); dedicated XnAP signaling, where the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process. That is, the second XnAP signaling may be RRC transfer extended for this scenario, or may be dedicated XnAP signaling introduced for this scenario.

Step 1206, the source base station receives the second XnAP signaling.

In a possible implementation manner, the source base station receives the second uplink SRB data through the RRC container in the second XnAP signaling.

Step 1207, the source base station sends the second uplink SRB data to the core network.

Correspondingly, the core network receives the second uplink SRB data.

In the presence of downlink SRB data, the following steps 1208 to 1110 will be executed.

Step 1208, the core network sends the second downlink SRB data.

In a possible implementation manner, the core network receives the second uplink SRB data sent by the source base station, and sends the second downlink SRB data to the source base station in order to feedback the second uplink SRB data.

Step 1209, the source base station receives the second downlink SRB data.

Step 1210, through the third XnAP signaling transmission channel between the first interfaces, the source base station sends the third XnAP signaling to the target base station, and the RRC container in the third XnAP signaling is used to transmit the PDCP encapsulated with the second downlink SRB data -C PDU, the third XnAP signaling transmission channel is established by the target base station based on the fourth UE XnAP identifier.

Optionally, the third XnAP signaling includes at least one of the following signaling: RRC transfer; dedicated XnAP signaling, where the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process. That is, the third XnAP signaling may be RRC transfer extended for this scenario, or may be dedicated XnAP signaling introduced for this scenario.

Step 1211, the target base station receives the third XnAP signaling.

In a possible implementation manner, the target base station receives the second downlink SRB data through the RRC container in the third XnAP signaling.

Step 1212, the target base station sends the second downlink SRB data to the terminal.

Correspondingly, the terminal receives the second downlink SRB data.

To sum up, the method provided in this embodiment is aimed at the small data transmission process triggered by the second uplink SRB data in the cell reselection scenario. For SRB data, the UE context of the terminal can be kept on the source base station side, and after sending the request for obtaining the UE context, the target base station transmits the second uplink SRB data through the RRC container in the XnAP signaling between the first interfaces.

At the same time, since the request for obtaining the UE context includes the UE XnAP identifier, the XnAP signaling transmission channel can be established through the UE XnAP identifier to realize the transmission of the second downlink SRB data.

It should be noted that, the foregoing method embodiments may be implemented separately, or may be implemented in combination, which is not limited in this application.

In each of the above embodiments, the steps performed by the target base station can independently implement the data transmission method in the cell reselection scenario on the side of the target base station, and the steps performed by the source base station can independently implement the cell reselection on the side of the source base station. The data transfer method in the scenario.

FIG. 13 shows a structural block diagram of a target device in a cell reselection scenario provided by an exemplary embodiment of the present application. The device can be realized as a target base station, or be realized as a part of the target base station, and the device includes: an uplink receiving module 1301 and uplink sending module 1302;

The uplink receiving module 1301 is configured to receive uplink inactive data sent by the terminal;

The uplink sending module 1302 is configured to send the uplink inactive data to the source device through a first interface, the UE context of the terminal is retained on the source device side, and the first interface is the target device a communication interface with the source device;

In an optional embodiment, the uplink sending module 1302 includes: a first tunnel information receiving submodule and an uplink sending submodule;

The first tunnel information receiving sub-module is configured to receive the first General Radio Packet Service Tunneling Protocol GTP tunnel information sent by the source device, where the first GTP tunnel information is used to indicate the first interface between the first interfaces. GTP tunnel;

The uplink sending submodule is configured to send the uplink inactive data to the source device through the first GTP tunnel between the first interfaces.

In an optional embodiment, the first tunnel information receiving submodule is configured to send a first message to the source device, where the first message is used to ask the source device for the UE context of the terminal , and is used to inform the source device that the terminal is performing the RA-SDT process; and receive a second message sent by the source device, where the second message includes the first GTP tunnel information.

In an optional embodiment, the first tunnel information receiving sub-module is configured to receive the I-RNTI sent by the terminal; address the source device based on the I-RNTI, and send to the source device the first message.

In an optional embodiment, the I-RNTI is carried in the RRC connection recovery request message.

In an optional embodiment, the first message includes at least one of the following information: a first UE XnAP identifier; a first UE context identifier; a first recovery MAC-I; and a first target cell identifier.

In an optional embodiment, the second message further includes: a first logical channel index.

In an optional embodiment, the first GTP tunnel information and the first logical channel index correspond to a first mapping relationship; the first tunnel information receiving submodule is configured to respond to receiving the first The second message stores the first mapping relationship.

In an optional embodiment, the second message further includes: terminal-specific RLC configuration information.

In an optional embodiment, the first logical channel index and the terminal-specific RLC configuration information are determined by the source device based on the UE context of the terminal retained on the side of the source device.

In an optional embodiment, the uplink sending submodule is configured to determine a logical channel corresponding to the uplink inactive data; The GTP tunnel transmits the PDCP PDU or RLC PDU of the uplink inactive data to the source device.

In an optional embodiment, the first GTP tunnel information includes at least one of the following information: a first IP address; and a first GTP TEID.

In an optional embodiment, the apparatus further includes: a second tunnel information sending module, a first downlink receiving module, and a first downlink sending module;

the second tunnel information sending module, configured to send second GTP tunnel information to the source device, where the second GTP tunnel message is used to indicate the second GTP tunnel between the first interfaces;

the first downlink receiving module, configured to receive downlink inactive data sent by the source device through the second GTP tunnel between the first interfaces;

The first downlink sending module is configured to send the downlink inactive state data to the terminal.

In an optional embodiment, the second tunnel information sending module is configured to send a third message to the source device, where the third message includes the second GTP tunnel information.

In an optional embodiment, the second tunnel information sending module is configured to send the third message to the source device after receiving the fourth message sent by the source device, the fourth message sent by the source device The message is used to inform the target device that the downlink inactive data arrives at the source device.

In an optional embodiment, the fourth message includes logical channel indication information, where the logical channel indication information is used to indicate a logical channel on which the second GTP tunnel needs to be established.

In an optional embodiment, the second tunnel information sending module is configured to send the third message to the source device after receiving the second message sent by the source device, the second message sent by the source device The message is used to provide the target base station with relevant information of the first GTP tunnel between the first interfaces established by the source base station for the logical channel supporting the transmission of inactive data.

In an optional embodiment, the second message includes a first logical channel index, where the first logical channel index is used to indicate a logical channel on which the second GTP tunnel needs to be established.

In an optional embodiment, the third message further includes: a second logical channel index.

In an optional embodiment, the second GTP tunnel information includes at least one of the following information: a second IP address; and a second GTP TEID.

In an optional embodiment, the first downlink receiving module is configured to receive the data through the second GTP tunnel corresponding to the logical channel of the downlink inactive data between the first interfaces. PDCP PDU or RLC PDU of the downlink inactive data sent by the source device.

In an optional embodiment, the inactive state data includes at least one of the following types of DRB data: SRB data.

In an optional embodiment, the uplink inactive state data includes: first uplink SRB data, and the uplink sending module 1302 includes: a fifth message sending submodule;

The fifth message sending submodule is configured to send a fifth message to the source device through the first interface, where the fifth message is used to request the UE context of the terminal from the source device, and, It is used to inform the source device that the terminal is performing the RA-SDT process, and the RRC container in the fifth message is used to transmit the PDCP-C PDU encapsulated with the first uplink SRB data.

In an optional embodiment, the fifth message includes at least one of the following information: a second UE XnAP identity; a second UE context identity; a second recovery MAC-I; and a second target cell identity.

In an optional embodiment, the apparatus further includes: a second downlink receiving module and a second downlink sending module;

The second downlink receiving module is configured to receive the first XnAP signaling sent by the source device through the first XnAP signaling transmission channel between the first interfaces, the RRC container in the first XnAP signaling For transmitting the PDCP-C PDU encapsulated with the first downlink SRB data, the first XnAP signaling transmission channel is established by the target base station based on the second UE XnAP identifier;

The second downlink sending module is configured to send the first downlink SRB data to the terminal.

In an optional embodiment, the first XnAP signaling includes at least one of the following signaling: RRC transfer; dedicated XnAP signaling, where the dedicated XnAP signaling is for SRB transmission in the SDT process Signaling generated from data.

In an optional embodiment, the uplink receiving module 1301 is configured to receive a first data indication message sent by the terminal, where the first data indication message is used to indicate that an uplink SRB exists in the RA-SDT process data.

In an optional embodiment, the first data indication message includes at least one of the following messages: recovery reason; MAC CE.

In an optional embodiment, the first uplink SRB data is uplink SRB data that has not undergone RLC segmentation and adopts a default RLC configuration.

In an optional embodiment, the uplink inactive state data includes: second uplink SRB data, and the uplink sending module 1302 includes: an XnAP identifier receiving sub-module and an XnAP signaling sending sub-module;

The XnAP identifier receiving sub-module is configured to receive a third UE XnAP identifier sent by the source base station, where the third UE XnAP identifier is used to indicate the second XnAP signaling transmission channel between the first interfaces;

The XnAP signaling sending sub-module is configured to send the second XnAP signaling to the source device through the second XnAP signaling transmission channel between the first interfaces, the RRC container in the second XnAP signaling used to transmit the PDCP-C PDU encapsulated with the second uplink SRB data.

In an optional embodiment, the XnAP identity receiving sub-module is configured to send a sixth message to the source base station, where the sixth message is used to request the UE context from the source base station, and is used to inform the source base station of the UE context The source base station and the terminal are performing the RA-SDT process; receiving the third UE XnAP identifier sent by the source base station.

In an optional embodiment, the sixth message includes a fourth UE XnAP identifier, and the apparatus further includes: a third downlink receiving module and a third downlink sending module;

The third downlink receiving module is configured to receive the third XnAP signaling sent by the source device through the third XnAP signaling transmission channel between the first interfaces, the RRC container in the third XnAP signaling For transmitting the PDCP-C PDU encapsulated with the second downlink SRB data, the third XnAP signaling transmission channel is established by the target base station based on the fourth UE XnAP identifier;

The third downlink sending module is configured to send the second downlink SRB data to the terminal.

In an optional embodiment, the third XnAP signaling includes at least one of the following signaling: RRC transfer; dedicated XnAP signaling, where the dedicated XnAP signaling is for SRB transmission in the SDT process Signaling generated from data.

In an optional embodiment, the uplink receiving module 1301 is configured to receive a second data indication message sent by the terminal, where the second data indication message is used to indicate that an uplink SRB exists in the RA-SDT process data.

In an optional embodiment, the second data indication message includes at least one of the following messages: recovery reason; MAC CE.

In an optional embodiment, the second XnAP signaling includes at least one of the following signaling: RRC transfer; dedicated XnAP signaling, where the dedicated XnAP signaling is for SRB transmission in the SDT process Signaling generated from data.

In an optional embodiment, the second uplink SRB data is uplink SRB data that adopts a default RLC configuration or adopts a terminal-specific RLC configuration.

FIG. 14 shows a structural block diagram of a source device in a cell reselection scenario provided by an exemplary embodiment of the present application. The device can be implemented as a source base station, or can be implemented as a part of the source base station. The device includes: an uplink receiving module 1401 and uplink sending module 1402;

The uplink receiving module 1401 is configured to receive uplink inactive data sent by a target device through a first interface, where the first interface is a communication interface between the target device and the source device;

The uplink sending module 1402 is configured to send the uplink inactive state data to the core network;

In an optional embodiment, the uplink receiving module 1401 includes: a first tunnel information sending submodule and an uplink receiving submodule;

The first tunnel information sending submodule is configured to send the first General Radio Packet Service Tunneling Protocol GTP tunnel information to the target device, where the first GTP tunnel information is used to indicate the first GTP between the first interfaces tunnel;

The uplink receiving sub-module is configured to receive the uplink inactive data sent by the target device through the first GTP tunnel between the first interfaces.

In an optional embodiment, the first tunnel information sending submodule is configured to receive a first message sent by the target device, where the first message is used to ask the source device for the UE of the terminal context, and is used to inform the source device that the terminal is performing the RA-SDT process; and send a second message to the target device, where the second message includes the first GTP tunnel information.

In an optional embodiment, the uplink receiving sub-module is configured to receive the target device through the first GTP tunnel corresponding to the logical channel of the uplink inactive data between the first interfaces PDCP PDU or RLC PDU of the sent uplink inactive data.

In an optional embodiment, the apparatus further includes: a first downlink receiving module, a second tunnel information receiving module, and a first downlink sending module;

the first downlink receiving module, configured to receive downlink inactive data sent by the core network;

the second tunnel information receiving module, configured to receive the second GTP tunnel information sent by the target device, where the second GTP tunnel message is used to indicate the second GTP tunnel between the first interfaces;

The first downlink sending module is configured to send the downlink inactive data to the target device through the second GTP tunnel between the first interfaces.

In an optional embodiment, the second tunnel information receiving module is configured to receive a third message sent by the target device, where the third message includes the second GTP tunnel information.

In an optional embodiment, the second tunnel information receiving module is configured to send a fourth message to the target device, where the fourth message is used to notify the target device that there is something in the source device The above downlink inactive data arrives.

In an optional embodiment, the second GTP tunnel information and the second logical channel index correspond to a second mapping relationship; the second tunnel information receiving module is configured to respond to receiving the third message to save the second mapping relationship.

In an optional embodiment, the first downlink sending module is configured to determine a logical channel corresponding to the downlink inactive data; The second GTP tunnel transmits the PDCP PDU or the radio link control protocol data unit RLC PDU of the downlink inactive data to the target device.

In an optional embodiment, the uplink inactive state data includes: first uplink SRB data, and the uplink receiving module 1401 includes: a fifth message receiving sub-module;

the fifth message receiving submodule is configured to receive, through the first interface, a fifth message sent by the target device, where the fifth message is used to request the source device for the UE context of the terminal, and is used to inform the source device that the terminal is performing the RA-SDT process, and the RRC container in the fifth message is used to transmit the PDCP-C PDU encapsulated with the first uplink SRB data.

the second downlink receiving module, configured to receive the first downlink SRB data sent by the core network;

The second downlink sending module is configured to send the first XnAP signaling to the target device through the first XnAP signaling transmission channel between the first interfaces, and the RRC container in the first XnAP signaling uses For transmitting the PDCP-C PDU encapsulated with the first downlink SRB data, the first XnAP signaling transmission channel is established by the target device based on the second UE XnAP identifier.

In an optional embodiment, the uplink inactive state data includes: second uplink SRB data, and the uplink receiving module 1401 includes: an XnAP identifier sending sub-module and an XnAP signaling receiving sub-module;

The XnAP identifier sending submodule is configured to send a third UE XnAP identifier to the target device, where the third UE XnAP identifier is used to indicate a second XnAP signaling transmission channel between the first interfaces;

The XnAP signaling receiving sub-module is configured to receive the second XnAP signaling sent by the target device through the second XnAP signaling transmission channel between the first interfaces, the RRC in the second XnAP signaling The container is used to transmit the PDCP-C PDU encapsulated with the second uplink SRB data.

In an optional embodiment, the XnAP identifier sending submodule is configured to receive, through the first interface, a sixth message sent by the target base station, where the sixth message is used to request the source base station UE context, and is used to inform the source base station that the terminal is performing the RA-SDT process; and send the third UE XnAP identity to the target base station.

the third downlink receiving module, configured to receive the second downlink SRB data sent by the core network;

The third downlink sending module is configured to send the third XnAP signaling to the target device through the third XnAP signaling transmission channel between the first interfaces, and the RRC container in the third XnAP signaling uses For transmitting the PDCP-C PDU encapsulated with the second downlink SRB data, the third XnAP signaling transmission channel is established by the target device based on the fourth UE XnAP identifier.

FIG. 15 shows a schematic structural diagram of a network device (source base station or target base station) provided by an exemplary embodiment of the present application. The network device includes: a processor 1501 , a receiver 1502 , a transmitter 1503 , a memory 1504 and a bus 1505 .

The processor 1501 includes one or more processing cores, and the processor 1501 executes various functional applications and information processing by running software programs and modules.

The receiver 1502 and the transmitter 1503 may be implemented as a communication component, which may be a communication chip.

The memory 1504 is connected to the processor 1501 through the bus 1505 .

The memory 1504 may be configured to store at least one instruction, and the processor 1501 may be configured to execute the at least one instruction to implement the various steps in the above method embodiments.

Additionally, memory 1504 may be implemented by any type or combination of volatile or non-volatile storage devices including, but not limited to, magnetic or optical disks, electrically erasable and programmable Read Only Memory (Electrically-Erasable Programmable Read Only Memory, EEPROM), Erasable Programmable Read Only Memory (EPROM), Static Random Access Memory (SRAM), Read Only Memory (Read-Only Memory, ROM), magnetic memory, flash memory, programmable read-only memory (Programmable Read-Only Memory, PROM).

Wherein, when the network device is implemented as a target base station, the processors and transceivers involved in the embodiments of the present application may execute the methods shown in any of the above-mentioned FIG. 7 to FIG. 9 and FIG. 11 to FIG. 12 . The steps to be performed are not repeated here.

In a possible implementation manner, when the network device implements the target base station,

Wherein, when the network device is implemented as a source base station, the processors and transceivers involved in the embodiments of the present application may perform any of the methods shown in FIG. 7 to FIG. 9 and FIG. 11 to FIG. 12 above. The steps to be performed are not repeated here.

In a possible implementation manner, when the network device is implemented as the source base station,

In an exemplary embodiment, a computer-readable storage medium is also provided, wherein the computer-readable storage medium stores at least one instruction, at least one piece of program, code set or instruction set, the at least one instruction, the At least one section of program, the code set or the instruction set is loaded and executed by the processor to implement the data transmission method in the cell reselection scenario performed by the network device provided by each of the above method embodiments.

In an exemplary embodiment, a chip is also provided, the chip includes a programmable logic circuit and/or program instructions, when the chip runs on a communication device, for implementing the cell reselection described in the above aspects The data transfer method in the scenario.

In an exemplary embodiment, a computer program product is also provided, when the computer program product runs on a processor of a computer device, the computer program product enables the communication device to execute the data transmission method in the cell reselection scenario described in the above aspects.

Those of ordinary skill in the art can understand that all or part of the steps of implementing the above embodiments can be completed by hardware, or can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. The storage medium mentioned may be a read-only memory, a magnetic disk or an optical disk, etc.

The above descriptions are only optional embodiments of the present application, and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the protection of the present application. within the range.

Claims

A data transmission method in a cell reselection scenario, characterized in that, when applied to a target base station, the method includes:

Receive uplink inactive data sent by the terminal;

The uplink inactive data is sent to the source base station through the first interface, the UE context of the terminal is retained on the source base station side, and the first interface is the communication between the target base station and the source base station interface;

The uplink inactive data is uplink data transmitted by the terminal through a small data transmission SDT process, and the SDT process is a small data transmission RA-SDT process based on random access.
The method according to claim 1, wherein the sending the uplink inactive data to the source base station through the first interface comprises:

receiving first General Radio Packet Service Tunneling Protocol GTP tunnel information sent by the source base station, where the first GTP tunnel information is used to indicate the first GTP tunnel between the first interfaces;

The uplink inactive data is sent to the source base station through the first GTP tunnel between the first interfaces.
The method according to claim 2, wherein the receiving the first GTP tunnel information sent by the source base station comprises:

sending a first message to the source base station, where the first message is used to ask the source base station for the UE context of the terminal, and used to inform the source base station that the terminal is performing the RA-SDT process;

A second message sent by the source base station is received, where the second message includes the first GTP tunnel information.
The method according to claim 3, wherein the sending the first message to the source base station comprises:

receiving the inactive wireless network temporary identifier I-RNTI sent by the terminal;

The source base station is addressed based on the I-RNTI, and the first message is sent to the source base station.
The method of claim 4, wherein:

The I-RNTI is carried in the radio resource control RRC connection recovery request message.
The method according to any one of claims 3 to 5, wherein the first message includes at least one of the following information:

The first UE XnAP identifier; the first UE context identifier; the first recovery MAC-I; the first target cell identifier.
The method according to any one of claims 3 to 6, wherein the second message further comprises:

The first logical channel index.
The method according to claim 7, wherein the first GTP tunnel information and the first logical channel index correspond to a first mapping relationship;

The method also includes:

In response to receiving the second message, the first mapping relationship is saved.
The method according to claim 7, wherein the second message further comprises:

Terminal dedicated radio link control RLC configuration information.
The method of claim 9, wherein:

The first logical channel index and the terminal-specific RLC configuration information are determined by the source base station based on the UE context of the terminal retained at the source base station side.
The method according to any one of claims 2 to 10, wherein the sending the uplink inactive data to the source base station through the first GTP tunnel between the first interfaces comprises:

determining the logical channel corresponding to the uplink inactive data;

The packet data convergence protocol protocol data unit PDCP PDU or radio link control protocol data unit RLC PDU of the uplink inactive data is transmitted through the first GTP tunnel corresponding to the logical channel between the first interfaces to the source base station.
The method according to any one of claims 2 to 11, wherein the first GTP tunnel information includes at least one of the following information:

IP address of the first network protocol;

The first GTP tunnel endpoint identifier TEID.
The method according to any one of claims 2 to 12, wherein the method further comprises:

sending second GTP tunnel information to the source base station, where the second GTP tunnel message is used to indicate the second GTP tunnel between the first interfaces;

receiving downlink inactive data sent by the source base station through the second GTP tunnel between the first interfaces;

Send the downlink inactive state data to the terminal.
The method according to claim 13, wherein the sending the second GTP tunnel information to the source base station comprises:

Send a third message to the source base station, where the third message includes the second GTP tunnel information.
The method according to claim 14, wherein the sending a third message to the source base station comprises:

After receiving the fourth message sent by the source base station, the third message is sent to the source base station, where the fourth message is used to inform the target base station that the source base station has the downlink inactive Status data arrives.
The method of claim 15, wherein:

The fourth message includes logical channel indication information, where the logical channel indication information is used to indicate a logical channel on which the second GTP tunnel needs to be established.
The method according to claim 14, wherein the sending a third message to the source base station comprises:

After receiving the second message sent by the source base station, the third message is sent to the source base station, where the second message is used to provide the target base station with the target base station for supporting the transmission of inactive state data The logical channel, the related information of the first GTP tunnel established between the first interfaces.
The method of claim 17, wherein:

The second message includes a first logical channel index, where the first logical channel index is used to indicate a logical channel on which the second GTP tunnel needs to be established.
The method according to any one of claims 14 to 18, wherein the third message further includes the following information:

Second logical channel index.
The method according to any one of claims 13 to 19, wherein the receiving downlink inactive data sent by the source base station through the second GTP tunnel between the first interfaces comprises:

The PDCP PDU or RLC PDU of the downlink inactive data sent by the source base station is received through the second GTP tunnel corresponding to the logical channel of the downlink inactive data between the first interfaces.
The method according to any one of claims 13 to 20, wherein the second GTP tunnel information includes at least one of the following information:

the second IP address;

Second GTP TEID.
The method according to any one of claims 2 to 21, wherein the inactive state data includes at least one of the following types:

Data radio bears DRB data;

Signaling radio bears SRB data.
The method according to claim 1, wherein the uplink inactive state data comprises: first uplink SRB data;

The sending the uplink inactive state data to the source base station through the first interface includes:

Send a fifth message to the source base station through the first interface, where the fifth message is used to ask the source base station for the UE context of the terminal, and is used to inform the source base station of the terminal During the RA-SDT process, the RRC container in the fifth message is used to transmit the Packet Data Convergence Protocol-Control Plane Protocol Data Unit PDCP-C PDU encapsulated with the first uplink SRB data.
The method according to claim 23, wherein the fifth message includes at least one of the following information:

The second UE XnAP identifier; the second UE context identifier; the second recovery MAC-I; the second target cell identifier.
The method of claim 24, wherein the method further comprises:

The first XnAP signaling sent by the source base station is received through the first XnAP signaling transmission channel between the first interfaces, and the RRC container in the first XnAP signaling is used to transmit the first downlink SRB encapsulated with the first downlink SRB. PDCP-C PDU of data, the first XnAP signaling transmission channel is established by the target base station based on the second UE XnAP identifier;

Send the first downlink SRB data to the terminal.
The method according to claim 25, wherein the first XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The method according to any one of claims 23 to 26, wherein the method further comprises:

Receive a first data indication message sent by the terminal, where the first data indication message is used to indicate that uplink SRB data exists in the RA-SDT process.
The method according to claim 27, wherein the first data indication message comprises at least one of the following messages:

reason for recovery;

Medium access control control cell MAC CE.
The method according to any one of claims 23 to 28, wherein,

The first uplink SRB data is uplink SRB data that has not undergone RLC segmentation and adopts a default RLC configuration.
The method according to claim 1, wherein the uplink inactive state data comprises: second uplink SRB data;

The sending the uplink inactive state data to the source base station through the first interface includes:

receiving a third UE XnAP identifier sent by the source base station, where the third UE XnAP identifier is used to indicate a second XnAP signaling transmission channel between the first interfaces;

The second XnAP signaling is sent to the source base station through the second XnAP signaling transmission channel between the first interfaces. The RRC container in the second XnAP signaling is used to transmit the second uplink SRB encapsulated with the second uplink SRB. PDCP-C PDU of data.
The method according to claim 30, wherein the receiving the third UE XnAP identifier sent by the source base station comprises:

sending a sixth message to the source base station, where the sixth message is used to ask the source base station for a UE context, and used to inform the source base station that the terminal is performing the RA-SDT process;

The third UE XnAP identifier sent by the source base station is received.
The method of claim 31, wherein the sixth message includes a fourth UE XnAP identity;

The method also includes:

The third XnAP signaling sent by the source base station is received through the third XnAP signaling transmission channel between the first interfaces, and the RRC container in the third XnAP signaling is used to transmit the encapsulated second downlink SRB data The PDCP-C PDU, the third XnAP signaling transmission channel is established by the target base station based on the fourth UE XnAP identification;

Send the second downlink SRB data to the terminal.
The method according to claim 32, wherein the third XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The method according to any one of claims 30 to 33, wherein the method further comprises:

Receive a second data indication message sent by the terminal, where the second data indication message is used to indicate that uplink SRB data exists in the RA-SDT process.
The method according to claim 34, wherein the second data indication message comprises at least one of the following messages:

reason for recovery;

MAC CE.
The method according to any one of claims 30 to 35, wherein the second XnAP signaling includes at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The method according to any one of claims 30 to 36, wherein,

The second uplink SRB data is uplink SRB data configured by a default RLC configuration or by using a terminal-specific RLC configuration.
A data transmission method in a cell reselection scenario, characterized in that, when applied to a source base station, a UE context of a terminal is retained on the source base station side, and the method includes:

receiving uplink inactive data sent by a target base station through a first interface, where the first interface is a communication interface between the target base station and the source base station;

sending the uplink inactive state data to the core network;

The uplink inactive data is uplink data transmitted by the terminal through a small data transmission SDT process, and the SDT process is a small data transmission RA-SDT process based on random access.
The method according to claim 38, wherein the receiving, through the first interface, uplink inactive data sent by the target base station comprises:

sending first general radio packet service tunneling protocol GTP tunnel information to the target base station, where the first GTP tunnel information is used to indicate the first GTP tunnel between the first interfaces;

The uplink inactive data sent by the target base station is received through the first GTP tunnel between the first interfaces.
The method according to claim 39, wherein the sending the first GTP tunnel information to the target base station comprises:

receiving a first message sent by the target base station, where the first message is used to ask the source base station for the UE context of the terminal, and used to inform the source base station that the terminal is performing the RA- SDT process;

Send a second message to the target base station, where the second message includes the first GTP tunnel information.
The method according to claim 40, wherein the first message includes at least one of the following information:

The first UE XnAP identifier; the first UE context identifier; the first recovery MAC-I; the first target cell identifier.
The method according to claim 40 or 41, wherein the second message further comprises:

The first logical channel index.
The method of claim 42, wherein the second message further comprises:

Terminal dedicated radio link control RLC configuration information.
The method of claim 43, wherein:

The first logical channel index and the terminal-specific RLC configuration information are determined by the source base station based on the UE context of the terminal retained at the source base station side.
The method according to any one of claims 39 to 44, wherein the receiving the uplink inactive data sent by the target base station through the first GTP tunnel between the first interfaces comprises:

Receive the packet data convergence protocol protocol data unit PDCP of the uplink inactive data sent by the target base station through the first GTP tunnel corresponding to the logical channel of the uplink inactive data between the first interfaces PDU or Radio Link Control Protocol Data Unit RLC PDU.
The method according to any one of claims 39 to 45, wherein the first GTP tunnel information includes at least one of the following information:

the IP address of the first network protocol;

The first GTP tunnel endpoint identifier TEID.
The method according to any one of claims 39 to 46, wherein the method further comprises:

receiving downlink inactive data sent by the core network;

receiving second GTP tunnel information sent by the target base station, where the second GTP tunnel message is used to indicate a second GTP tunnel between the first interfaces;

The downlink inactive data is sent to the target base station through the second GTP tunnel between the first interfaces.
The method according to claim 47, wherein the receiving the second GTP tunnel information sent by the target base station comprises:

A third message sent by the target base station is received, where the third message includes the second GTP tunnel information.
The method of claim 48, wherein the method further comprises:

Send a fourth message to the target base station, where the fourth message is used to inform the target base station that the downlink inactive data arrives at the source base station.
The method of claim 49, wherein:

The fourth message includes logical channel indication information, where the logical channel indication information is used to indicate a logical channel on which the second GTP tunnel needs to be established.
The method according to any one of claims 48 to 50, wherein the third message further comprises:

Second logical channel index.
The method according to claim 51, wherein the second GTP tunnel information and the second logical channel index correspond to a second mapping relationship;

The method also includes:

In response to receiving the third message, the second mapping relationship is saved.
The method according to any one of claims 47 to 52, wherein the sending the downlink inactive data to the target base station through the second GTP tunnel between the first interfaces comprises:

determining the logical channel corresponding to the downlink inactive data;

The packet data convergence protocol protocol data unit PDCP PDU or radio link control protocol data unit RLC PDU of the downlink inactive data is transmitted through the second GTP tunnel corresponding to the logical channel between the first interfaces to the target base station.
The method according to any one of claims 47 to 53, wherein the second GTP tunnel information includes at least one of the following information:

the second IP address;

Second GTP TEID.
The method according to any one of claims 39 to 54, wherein the inactive state data includes at least one of the following types:

Data radio bears DRB data;

Signaling radio bears SRB data.
The method according to claim 38, wherein the uplink inactive state data comprises: first uplink SRB data;

The receiving, through the first interface, uplink inactive data sent by the target base station includes:

Through the first interface, a fifth message sent by the target base station is received, where the fifth message is used to ask the source base station for the UE context of the terminal, and is used to notify the source base station of the The terminal is performing the RA-SDT process, and the RRC container in the fifth message is used to transmit the Packet Data Convergence Protocol-Control Plane Protocol Data Unit PDCP-C PDU encapsulated with the first uplink SRB data.
The method of claim 56, wherein the fifth message includes at least one of the following information:

The second UE XnAP identifier; the second UE context identifier; the second recovery MAC-I; the second target cell identifier.
The method of claim 57, wherein the method further comprises:

receiving the first downlink SRB data sent by the core network;

The first XnAP signaling is sent to the target base station through the first XnAP signaling transmission channel between the first interfaces, and the RRC container in the first XnAP signaling is used to transmit the first downlink encapsulated with the first downlink. PDCP-C PDU of SRB data, the first XnAP signaling transmission channel is established by the target base station based on the second UE XnAP identifier.
The method of claim 58, wherein the first XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The method according to any one of claims 56 to 59, wherein,

The first uplink SRB data is uplink SRB data that has not undergone RLC segmentation and adopts a default RLC configuration.
The method according to claim 38, wherein the uplink inactive state data comprises: second uplink SRB data;

The receiving, through the first interface, uplink inactive data sent by the target base station includes:

sending a third UE XnAP identifier to the target base station, where the third UE XnAP identifier is used to indicate a second XnAP signaling transmission channel between the first interfaces;

The second XnAP signaling sent by the target base station is received through the second XnAP signaling transmission channel between the first interfaces, and the RRC container in the second XnAP signaling is used to transmit the second uplink encapsulated with the second XnAP signaling. PDCP-C PDU for SRB data.
The method according to claim 59, wherein the sending a third UE XnAP identifier to the target base station comprises:

receiving a sixth message sent by the target base station, where the sixth message is used to request the UE context from the source base station, and is used to inform the source base station that the terminal is performing the RA-SDT process;

Send the third UE XnAP identity to the target base station.
The method of claim 62, wherein the sixth message includes a fourth UE XnAP identity;

The method also includes:

receiving the second downlink SRB data sent by the core network;

The third XnAP signaling is sent to the target base station through the third XnAP signaling transmission channel between the first interfaces, and the RRC container in the third XnAP signaling is used to transmit the second downlink SRB encapsulated with the second downlink SRB. PDCP-C PDU of data, the third XnAP signaling transmission channel is established by the target base station based on the fourth UE XnAP identifier.
The method of claim 63, wherein the third XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The method according to any one of claims 61 to 64, wherein the second XnAP signaling includes at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The method according to any one of claims 61 to 65, wherein,

The second uplink SRB data is uplink SRB data configured by a default RLC configuration or by using a terminal-specific RLC configuration.
A target device in a cell reselection scenario, characterized in that the device comprises: an uplink receiving module and an uplink transmitting module;

The uplink receiving module is used for receiving uplink inactive data sent by the terminal;

The uplink sending module is configured to send the uplink inactive data to the source device through a first interface, the UE context of the terminal is retained on the source device side, and the first interface is the connection between the target device and the source device. a communication interface between the source devices;

The uplink inactive data is uplink data transmitted by the terminal through a small data transmission SDT process, and the SDT process is a small data transmission RA-SDT process based on random access.
The apparatus according to claim 67, wherein the uplink sending module comprises: a first tunnel information receiving submodule and an uplink sending submodule;

The first tunnel information receiving sub-module is configured to receive the first General Radio Packet Service Tunneling Protocol GTP tunnel information sent by the source device, where the first GTP tunnel information is used to indicate the first interface between the first interfaces. GTP tunnel;

The uplink sending submodule is configured to send the uplink inactive data to the source device through the first GTP tunnel between the first interfaces.
The apparatus according to claim 68, wherein the first tunnel information receiving submodule is configured to:

sending a first message to the source device, the first message for requesting the UE context of the terminal from the source device, and for informing the source device that the terminal is performing the RA-SDT process;

A second message sent by the source device is received, where the second message includes the first GTP tunnel information.
The device according to claim 69, wherein the first tunnel information receiving submodule is configured to:

receiving the inactive wireless network temporary identifier I-RNTI sent by the terminal;

The first message is sent to the source device by addressing the source device based on the I-RNTI.
The apparatus of claim 70, wherein:

The I-RNTI is carried in the radio resource control RRC connection recovery request message.
The apparatus according to any one of claims 69 to 71, wherein the first message includes at least one of the following information:

The first UE XnAP identifier; the first UE context identifier; the first recovery MAC-I; the first target cell identifier.
The apparatus according to any one of claims 69 to 72, wherein the second message further comprises:

The first logical channel index.
The apparatus according to claim 73, wherein the first GTP tunnel information and the first logical channel index correspond to a first mapping relationship;

The first tunnel information receiving submodule is configured to store the first mapping relationship in response to receiving the second message.
The apparatus of claim 73, wherein the second message further comprises:

Terminal dedicated radio link control RLC configuration information.
The apparatus of claim 75, wherein

The first logical channel index and the terminal-specific RLC configuration information are determined by the source device based on the UE context of the terminal retained at the source device side.
The device according to any one of claims 68 to 76, wherein the uplink transmission sub-module is configured to:

determining the logical channel corresponding to the uplink inactive data;

The packet data convergence protocol protocol data unit PDCP PDU or radio link control protocol data unit RLC PDU of the uplink inactive data is transmitted through the first GTP tunnel corresponding to the logical channel between the first interfaces to the source device.
The apparatus according to any one of claims 68 to 77, wherein the first GTP tunnel information includes at least one of the following information:

IP address of the first network protocol;

The first GTP tunnel endpoint identifier TEID.
The apparatus according to any one of claims 68 to 78, wherein the apparatus further comprises: a second tunnel information sending module, a first downlink receiving module, and a first downlink sending module;

the second tunnel information sending module, configured to send second GTP tunnel information to the source device, where the second GTP tunnel message is used to indicate the second GTP tunnel between the first interfaces;

the first downlink receiving module, configured to receive downlink inactive data sent by the source device through the second GTP tunnel between the first interfaces;

The first downlink sending module is configured to send the downlink inactive state data to the terminal.
The apparatus of claim 79, wherein:

The second tunnel information sending module is configured to send a third message to the source device, where the third message includes the second GTP tunnel information.
The apparatus of claim 80, wherein:

The second tunnel information sending module is configured to send the third message to the source device after receiving the fourth message sent by the source device, where the fourth message is used to notify the target device The downlink inactive data arrives at the source device.
The apparatus of claim 81, wherein:

The fourth message includes logical channel indication information, where the logical channel indication information is used to indicate a logical channel on which the second GTP tunnel needs to be established.
The apparatus of claim 80, wherein:

The second tunnel information sending module is configured to send the third message to the source device after receiving the second message sent by the source device, where the second message is used to provide the target base station with Information about the first GTP tunnel between the first interfaces established by the source base station for a logical channel supporting the transmission of inactive data.
The apparatus of claim 83, wherein:

The second message includes a first logical channel index, where the first logical channel index is used to indicate a logical channel on which the second GTP tunnel needs to be established.
The apparatus according to any one of claims 80 to 84, wherein the third message further comprises:

Second logical channel index.
The device according to any one of claims 79 to 85, characterized in that,

The first downlink receiving module is configured to receive the downlink inactive sent by the source device through the second GTP tunnel corresponding to the logical channel of the downlink inactive data between the first interfaces PDCP PDU or RLC PDU of status data.
The apparatus according to any one of claims 79 to 86, wherein the second GTP tunnel information includes at least one of the following information:

the second IP address;

Second GTP TEID.
The device according to any one of claims 68 to 87, wherein the inactive state data includes at least one of the following types:

Data radio bears DRB data;

Signaling radio bears SRB data.
The device according to claim 67, wherein the uplink inactive state data comprises: first uplink SRB data, and the uplink sending module comprises: a fifth message sending sub-module;

The fifth message sending submodule is configured to send a fifth message to the source device through the first interface, where the fifth message is used to request the UE context of the terminal from the source device, and, is used to inform the source device that the terminal is performing the RA-SDT process, and the RRC container in the fifth message is used to transmit the packet data convergence protocol-control plane protocol encapsulated with the first uplink SRB data Data unit PDCP-C PDU.
The apparatus according to claim 89, wherein the fifth message includes at least one of the following information:

The second UE XnAP identifier; the second UE context identifier; the second recovery MAC-I; the second target cell identifier.
The apparatus according to claim 90, wherein the apparatus further comprises: a second downlink receiving module and a second downlink sending module;

The second downlink receiving module is configured to receive the first XnAP signaling sent by the source device through the first XnAP signaling transmission channel between the first interfaces, the RRC container in the first XnAP signaling For transmitting the PDCP-C PDU encapsulated with the first downlink SRB data, the first XnAP signaling transmission channel is established by the target base station based on the second UE XnAP identifier;

The second downlink sending module is configured to send the first downlink SRB data to the terminal.
The apparatus of claim 91, wherein the first XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The device according to any one of claims 89 to 92, characterized in that:

The uplink receiving module is configured to receive a first data indication message sent by the terminal, where the first data indication message is used to indicate that uplink SRB data exists in the RA-SDT process.
The apparatus according to claim 93, wherein the first data indication message comprises at least one of the following messages:

reason for recovery;

Medium access control control cell MAC CE.
The device according to any one of claims 89 to 94, characterized in that,

The first uplink SRB data is uplink SRB data that has not undergone RLC segmentation and adopts a default RLC configuration.
The device according to claim 67, wherein the uplink inactive state data comprises: second uplink SRB data, and the uplink sending module comprises: an XnAP identification receiving sub-module and an XnAP signaling sending sub-module;

The XnAP identifier receiving sub-module is configured to receive a third UE XnAP identifier sent by the source base station, where the third UE XnAP identifier is used to indicate the second XnAP signaling transmission channel between the first interfaces;

The XnAP signaling sending sub-module is configured to send the second XnAP signaling to the source device through the second XnAP signaling transmission channel between the first interfaces, the RRC container in the second XnAP signaling used to transmit the PDCP-C PDU encapsulated with the second uplink SRB data.
The device according to claim 96, wherein the XnAP identification receiving sub-module is used for,

sending a sixth message to the source base station, where the sixth message is used to ask the source base station for a UE context, and used to inform the source base station that the terminal is performing the RA-SDT process;

The third UE XnAP identifier sent by the source base station is received.
The apparatus according to claim 97, wherein the sixth message includes a fourth UE XnAP identifier, and the apparatus further comprises: a third downlink receiving module and a third downlink sending module;

The third downlink receiving module is configured to receive the third XnAP signaling sent by the source device through the third XnAP signaling transmission channel between the first interfaces, the RRC container in the third XnAP signaling For transmitting the PDCP-C PDU encapsulated with the second downlink SRB data, the third XnAP signaling transmission channel is established by the target base station based on the fourth UE XnAP identifier;

The third downlink sending module is configured to send the second downlink SRB data to the terminal.
The apparatus according to claim 98, wherein the third XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The device according to any one of claims 96 to 99, characterized in that,

The uplink receiving module is configured to receive a second data indication message sent by the terminal, where the second data indication message is used to indicate that uplink SRB data exists in the RA-SDT process.
The apparatus according to claim 100, wherein the second data indication message comprises at least one of the following messages:

reason for recovery;

MAC CE.
The apparatus according to any one of claims 96 to 101, wherein the second XnAP signaling includes at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The device according to any one of claims 96 to 102, characterized in that:

The second uplink SRB data is uplink SRB data configured by a default RLC configuration or by using a terminal-specific RLC configuration.
A source device in a cell reselection scenario, characterized in that a UE context of a terminal is retained on the source device side, and the device includes: an uplink receiving module and an uplink sending module;

The uplink receiving module is configured to receive uplink inactive data sent by the target device through a first interface, where the first interface is a communication interface between the target device and the source device;

The uplink sending module is configured to send the uplink inactive state data to the core network;

The uplink inactive data is uplink data transmitted by the terminal through a small data transmission SDT process, and the SDT process is a small data transmission RA-SDT process based on random access.
The apparatus according to claim 104, wherein the uplink receiving module comprises: a first tunnel information sending submodule and an uplink receiving submodule;

The first tunnel information sending submodule is configured to send the first General Radio Packet Service Tunneling Protocol GTP tunnel information to the target device, where the first GTP tunnel information is used to indicate the first GTP between the first interfaces tunnel;

The uplink receiving sub-module is configured to receive the uplink inactive data sent by the target device through the first GTP tunnel between the first interfaces.
The apparatus according to claim 105, wherein the first tunnel information sending submodule is configured to:

receiving a first message sent by the target device, where the first message is used to ask the source device for the UE context of the terminal, and used to inform the source device that the terminal is performing the RA- SDT process;

A second message is sent to the target device, the second message including the first GTP tunnel information.
The apparatus according to claim 106, wherein the first message includes at least one of the following information:

The first UE XnAP identifier; the first UE context identifier; the first recovery MAC-I; the first target cell identifier.
The apparatus according to claim 106 or 107, wherein the second message further comprises:

The first logical channel index.
The apparatus of claim 108, wherein the second message further comprises:

Terminal dedicated radio link control RLC configuration information.
The apparatus of claim 109, wherein:

The first logical channel index and the terminal-specific RLC configuration information are determined by the source device based on the UE context of the terminal retained at the source device side.
The device according to any one of claims 105 to 110, characterized in that:

The uplink receiving sub-module is configured to receive the uplink inactive data sent by the target device through the first GTP tunnel corresponding to the logical channel of the uplink inactive data between the first interfaces The Packet Data Convergence Protocol Protocol Data Unit PDCP PDU or Radio Link Control Protocol Data Unit RLC PDU.
The apparatus according to any one of claims 105 to 111, wherein the first GTP tunnel information includes at least one of the following information:

IP address of the first network protocol;

The first GTP tunnel endpoint identifier TEID.
The apparatus according to any one of claims 105 to 112, wherein the apparatus further comprises: a first downlink receiving module, a second tunnel information receiving module, and a first downlink sending module;

the first downlink receiving module, configured to receive downlink inactive data sent by the core network;

the second tunnel information receiving module, configured to receive the second GTP tunnel information sent by the target device, where the second GTP tunnel message is used to indicate the second GTP tunnel between the first interfaces;

The first downlink sending module is configured to send the downlink inactive data to the target device through the second GTP tunnel between the first interfaces.
The apparatus according to claim 113, wherein the second tunnel information receiving module is configured to:

A third message sent by the target device is received, where the third message includes the second GTP tunnel information.
The apparatus of claim 114, wherein:

The second tunnel information receiving module is configured to send a fourth message to the target device, where the fourth message is used to inform the target device that the downlink inactive data arrives at the source device.
The apparatus of claim 115, wherein:

The fourth message includes logical channel indication information, where the logical channel indication information is used to indicate a logical channel on which the second GTP tunnel needs to be established.
The apparatus according to any one of claims 114 to 116, wherein the third message further comprises:

Second logical channel index.
The apparatus according to claim 117, wherein the second GTP tunnel information and the second logical channel index correspond to a second mapping relationship;

The second tunnel information receiving module is configured to store the second mapping relationship in response to receiving the third message.
The apparatus according to any one of claims 113 to 118, wherein the first downlink sending module is configured to:

determining the logical channel corresponding to the downlink inactive data;

The packet data convergence protocol protocol data unit PDCP PDU or radio link control protocol data unit RLC PDU of the downlink inactive data is transmitted through the second GTP tunnel corresponding to the logical channel between the first interfaces to the target device.
The apparatus according to any one of claims 113 to 119, wherein the second GTP tunnel information includes at least one of the following information:

the second IP address;

Second GTP TEID.
The apparatus according to any one of claims 105 to 120, wherein the inactive state data includes at least one of the following types:

Data radio bears DRB data;

Signaling radio bears SRB data.
The apparatus according to claim 104, wherein the uplink inactive state data comprises: first uplink SRB data, and the uplink receiving module comprises: a fifth message receiving sub-module;

the fifth message receiving submodule is configured to receive, through the first interface, a fifth message sent by the target device, where the fifth message is used to request the source device for the UE context of the terminal, and , used to inform the source device that the terminal is performing the RA-SDT process, and the RRC container in the fifth message is used to transmit the packet data convergence protocol-control plane encapsulated with the first uplink SRB data Protocol Data Unit PDCP-C PDU.
The apparatus according to claim 122, wherein the fifth message includes at least one of the following information:

The second UE XnAP identifier; the second UE context identifier; the second recovery MAC-I; the second target cell identifier.
The apparatus according to claim 123, wherein the apparatus further comprises: a second downlink receiving module and a second downlink sending module;

the second downlink receiving module, configured to receive the first downlink SRB data sent by the core network;

The second downlink sending module is configured to send the first XnAP signaling to the target device through the first XnAP signaling transmission channel between the first interfaces, and the RRC container in the first XnAP signaling uses For transmitting the PDCP-C PDU encapsulated with the first downlink SRB data, the first XnAP signaling transmission channel is established by the target device based on the second UE XnAP identifier.
The apparatus of claim 124, wherein the first XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The device according to any one of claims 122 to 125, characterized in that:

The first uplink SRB data is uplink SRB data that has not undergone RLC segmentation and adopts a default RLC configuration.
The device according to claim 104, wherein the uplink inactive state data comprises: second uplink SRB data, and the uplink receiving module comprises: an XnAP identifier sending sub-module and an XnAP signaling receiving sub-module;

The XnAP identifier sending submodule is configured to send a third UE XnAP identifier to the target device, where the third UE XnAP identifier is used to indicate a second XnAP signaling transmission channel between the first interfaces;

The XnAP signaling receiving sub-module is configured to receive the second XnAP signaling sent by the target device through the second XnAP signaling transmission channel between the first interfaces, the RRC in the second XnAP signaling The container is used to transmit the PDCP-C PDU encapsulated with the second uplink SRB data.
The device according to claim 127, wherein the XnAP identification sending submodule is used for:

Through the first interface, a sixth message sent by the target base station is received, where the sixth message is used to ask the source base station for a UE context, and is used to inform the source base station that the terminal is performing the RA-SDT process;

Send the third UE XnAP identity to the target base station.
The apparatus according to claim 128, wherein the sixth message includes a fourth UE XnAP identifier, and the apparatus further comprises: a third downlink receiving module and a third downlink sending module;

the third downlink receiving module, configured to receive the second downlink SRB data sent by the core network;

The third downlink sending module is configured to send the third XnAP signaling to the target device through the third XnAP signaling transmission channel between the first interfaces, and the RRC container in the third XnAP signaling uses For transmitting the PDCP-C PDU encapsulated with the second downlink SRB data, the third XnAP signaling transmission channel is established by the target device based on the fourth UE XnAP identifier.
The apparatus according to claim 129, wherein the third XnAP signaling comprises at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The apparatus according to any one of claims 127 to 130, wherein the second XnAP signaling includes at least one of the following signaling:

RRC transfer;

Dedicated XnAP signaling, the dedicated XnAP signaling is signaling generated for transmitting SRB data in the SDT process.
The device according to any one of claims 127 to 131, characterized in that:

The second uplink SRB data is uplink SRB data configured by a default RLC configuration or by using a terminal-specific RLC configuration.
A network device, characterized in that the network device comprises: a transceiver; wherein,

the transceiver, configured to receive uplink inactive data sent by the terminal;

The transceiver is configured to send the uplink inactive data to the source base station through a first interface, the UE context of the terminal is retained on the source base station side, and the first interface is the connection between the network device and the source base station. the communication interface between the source base stations;

The uplink inactive data is uplink data transmitted by the terminal through a small data transmission SDT process, and the SDT process is a small data transmission RA-SDT process based on random access.
A network device, characterized in that the network device comprises: a transceiver; wherein,

the transceiver, configured to receive uplink inactive data sent by a target base station through a first interface, where the first interface is a communication interface between the network device and the target base station;

the transceiver, configured to send the uplink inactive state data to the core network;

The uplink inactive data is uplink data transmitted by the terminal through a small data transmission SDT process, the SDT process is a small data transmission RA-SDT process based on random access, and the UE context of the terminal is reserved in the network device side.
A computer-readable storage medium, wherein executable instructions are stored in the readable storage medium, and the executable instructions are loaded and executed by a processor to implement the cell according to any one of claims 1 to 66 Reselect the data transmission method in the scenario.