CN115002924A

CN115002924A - Uplink small data transmission method, network side DU and network side CU

Info

Publication number: CN115002924A
Application number: CN202210621812.2A
Authority: CN
Inventors: 孙建成; 汪颖
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2018-02-08
Filing date: 2018-02-08
Publication date: 2022-09-02
Also published as: CN110139386A

Abstract

The embodiment of the invention discloses a transmission method of uplink small data, a network side DU and a network side CU, wherein the method comprises the following steps: a network side DU receives an uplink message and uplink small data sent by a target user terminal in an inactive state; the network side DU acquires the context of the target user terminal; the network side DU sends the uplink small data to a network side CU; and the network side DU sends a reply message of the uplink message to the target user terminal. The embodiment of the invention can support the uplink small data transmission in the non-activated state under the CU and DU separation architecture.

Description

Uplink small data transmission method, network side DU and network side CU

The invention is a divisional application of an invention application with the application date of 2018, 2 and 8 months and the application number of 2018101281354, and the invention name of the invention is 'a transmission method of uplink small data, a network side DU and a network side CU'.

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a transmission method of uplink small data, a Distributed Unit (DU) on a network side, and a Centralized Unit (CU) on the network side.

Background

Fifth generation (5) ^th generation, 5G) communication system newly introduces an Inactive state (Inactive state) for the state of the ue, in addition to a connected state (connected state) and an idle state (idle state). The user terminal can perform cell reselection, receive system information broadcast, receive paging messages and the like in an inactive state, and can quickly recover to a connected state. In addition, there is also small data in the 5G communication system, which is data with a relatively small data amount, for example: a small data volume messaging message or a small data volume picture, etc. And in the 5G communication system, a separation architecture of CU and DU is newly introduced at the network side. Therefore, under the CU and DU separation architecture, how to support uplink small data transmission in the inactive state is a technical problem that needs to be solved urgently at present.

Disclosure of Invention

The embodiment of the invention provides a transmission method of uplink small data, a network side DU and a network side CU, and aims to solve the problem of how to support uplink small data transmission in an inactive state under a CU and DU separation architecture.

The embodiment of the invention provides a method for transmitting uplink small data, which comprises the following steps:

a network side DU receives an uplink message and uplink small data sent by a target user terminal in an inactive state;

the network side DU acquires the context of the target user terminal;

the network side DU sends the uplink small data to the network side CU;

and the network side DU sends a reply message of the uplink message to the target user terminal.

Optionally, if the uplink message includes a Media Access Control Element (MAC CE) message, the obtaining, by the network side DU, a context of the target ue includes:

the network side DU acquires the context identifier of the target user terminal from the MAC CE message;

and the network side DU searches and obtains the context of the target user terminal according to the context identifier.

Optionally, if the uplink message includes a Radio Resource Control (RRC) message, the obtaining, by the network side DU, the context of the target ue includes:

if the uplink message comprises the RRC message, the network side DU sending an access request for the target ue to the network side CU, wherein the access request comprises the RRC message;

the network side DU accepts the context establishment procedure of the target ue initiated by the network side CU to establish the context of the target ue.

Optionally, if the uplink message includes the RRC message, the reply message of the RRC message is a reply message that the network side DU receives and is sent by the network side CU; or

If the uplink message includes the MAC CE message, the reply message of the MAC CE message is generated for the network side DU.

Optionally, when a Control Plane (CP) and a User Plane (UP) of the network-side CU are separated, the sending, by the network-side DU, the uplink small data to the network-side CU includes:

and the network side DU sends the uplink small data to the UP of the network side CU.

Optionally, if the target ue establishes a connection with the network side DU before entering the inactive state, the network side DU retains the context of the target ue after the target ue accesses the inactive state.

Optionally, the method further includes:

under the condition that the network side DU cannot acquire the context of the target user terminal, the network side DU sends an access request aiming at the target user terminal to a network side CU;

The embodiment of the invention also provides a method for transmitting uplink small data, which comprises the following steps:

and the network side CU receives the uplink small data which are sent by the network side DU and aim at the target user terminal in the non-activated state.

Optionally, the method further includes:

the CU at the network side receives an access request of the target user terminal sent by the DU at the network side, wherein the access request comprises an RRC message of the target user terminal;

the CU at the network side acquires the context identifier of the target user terminal from the RRC message;

the CU at the network side acquires the context of the target user terminal according to the context identifier;

and the CU at the network side initiates a context establishment process of the target user terminal to the DU at the network side.

Optionally, the obtaining, by the network side CU, the context of the target user terminal according to the context identifier includes:

the network side CU acquires the context of the target user terminal, which is pre-stored by the network side CU, according to the context identifier; or

And under the condition that the network side CU does not store the context of the target user terminal, the network side CU acquires the context of the target user terminal from a target base station connected with the target user terminal according to the context identifier.

Optionally, under the condition that the CP and the UP of the network side CU are separated, the receiving, by the network side CU, the uplink small data, which is sent by the network side DU and is addressed to the target user terminal in the inactive state, by the network side CU includes:

and the UP of the network side CU receives the uplink small data which is sent by the network side DU and aims at the target user terminal in the non-activated state.

Optionally, the method further includes:

the CU at the network side receives an access request aiming at the target user terminal sent by the DU at the network side;

and the network side CU initiates a context establishment process of the target user terminal to the network side DU.

The embodiment of the present invention further provides a network side DU, including:

the receiving module is used for receiving the uplink message and the uplink small data sent by the target user terminal in the inactive state;

an obtaining module, configured to obtain a context of the target user terminal;

the first sending module is used for sending the uplink small data to a network side CU;

and the second sending module is used for sending the reply message of the uplink message to the target user terminal.

An embodiment of the present invention further provides a network-side CU, including:

and the receiving module is used for receiving uplink small data which are sent by the network side DU and aim at the target user terminal in the non-activated state.

The embodiment of the present invention further provides a network side DU, including: a transceiver, a memory, a processor, and a computer program stored on the memory and executable on the processor,

the transceiver is used for receiving uplink messages and uplink small data sent by the target user terminal in the inactive state;

the processor is configured to obtain a context of the target user terminal;

the transceiver is used for sending the uplink small data to a network side CU;

and the transceiver is used for sending the reply message of the uplink message to the target user terminal.

Optionally, if the uplink message includes an MAC CE message, the obtaining the context of the target ue includes:

acquiring the context identifier of the target user terminal from the MAC CE message;

and searching and obtaining the context of the target user terminal according to the context identifier.

Optionally, if the uplink message includes an RRC message, the obtaining the context of the target ue includes:

sending an access request aiming at the target user terminal to the network side CU under the condition that the uplink message comprises the RRC message, wherein the access request comprises the RRC message;

and receiving the context establishing process of the target user terminal initiated by the CU at the network side so as to establish the context of the target user terminal.

Optionally, if the uplink message includes the RRC message, the reply message of the RRC message is a reply message that the network side DU receives the network side CU; or

If the uplink message includes the MAC CE message, a reply message of the MAC CE message is generated for the network side DU.

Optionally, in a case that the CP and the UP of the network-side CU are separated, the sending the uplink small data to the network-side CU includes:

and sending the uplink small data to UP of the network side CU.

Optionally, the transceiver is further configured to:

sending an access request for the target user terminal to the network side CU under the condition that the network side DU cannot acquire the context of the target user terminal;

An embodiment of the present invention further provides a network-side CU, including: a transceiver, a memory, a processor, and a computer program stored on the memory and executable on the processor,

the transceiver is configured to receive uplink small data, which is sent by a network side DU and is addressed to a target user terminal in an inactive state.

Optionally, the transceiver is further configured to: receiving an access request of the target user terminal sent by the network side DU, wherein the access request comprises an RRC message of the target user terminal;

the processor is further configured to obtain a context identifier of the target ue from the RRC message;

the processor is further configured to obtain a context of the target user terminal according to the context identifier;

the transceiver is further configured to initiate a context establishment procedure of the target user terminal to the network side DU.

Optionally, the obtaining the context of the target user terminal according to the context identifier includes:

acquiring the context of the target user terminal pre-stored by the CU at the network side according to the context identifier; or

And under the condition that the network side CU does not store the context of the target user terminal, acquiring the context of the target user terminal from a target base station connected with the target user terminal according to the context identifier.

Optionally, under the condition that the CP and the UP of the network side CU are separated, the receiving uplink small data, which is sent by the network side DU and is addressed to the target user terminal in the inactive state, includes:

Optionally, the transceiver is further configured to:

receiving an access request aiming at the target user terminal sent by the network side DU;

and initiating a context establishing process of the target user terminal to the network side DU.

The embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps in the method for transmitting uplink small data of a network side DU provided in the embodiment of the present invention, or the computer program, when executed by the processor, implements the steps in the method for transmitting uplink small data of a network side CU provided in the embodiment of the present invention.

Thus, in the embodiment of the present invention, the network side DU receives the uplink message and the uplink small data sent by the target user terminal in the inactive state; the network side DU acquires the context of the target user terminal; the network side DU sends the uplink small data to a network side CU; and the network side DU sends a reply message of the uplink message to the target user terminal. The embodiment of the invention can support the uplink small data transmission in the non-activated state under the CU and DU separation architecture, and can improve the transmission efficiency of the user terminal.

Drawings

FIG. 1 is a schematic diagram of a network architecture to which embodiments of the present invention are applicable;

fig. 2 is a schematic diagram of a network structure of a CU-DU separation architecture to which an embodiment of the present invention is applicable;

fig. 3 is a schematic diagram of a CU separation architecture according to an embodiment of the present invention;

fig. 4 is a flowchart of a method for transmitting uplink small data according to an embodiment of the present invention;

fig. 5 is a flowchart of another uplink small data transmission method according to an embodiment of the present invention;

fig. 6 is a schematic diagram illustrating transmission of uplink small data according to an embodiment of the present invention;

fig. 7 is a schematic diagram of another uplink small data transmission provided in the embodiment of the present invention;

fig. 8 is a structural diagram of a network side DU according to an embodiment of the present invention;

fig. 9 is a block diagram of another network side DU provided in an embodiment of the present invention;

fig. 10 is a block diagram of another network side DU provided in an embodiment of the present invention;

fig. 11 is a block diagram of another network side DU provided in an embodiment of the present invention;

FIG. 12 is a block diagram of a network-side CU according to an embodiment of the present invention;

FIG. 13 is a block diagram of another network-side CU, in accordance with an embodiment of the present invention;

FIG. 14 is a block diagram of another network-side CU, in accordance with an embodiment of the present invention;

fig. 15 is a block diagram of another network side DU provided in an embodiment of the present invention;

fig. 16 is a block diagram of another network-side CU according to an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

To make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1, fig. 1 is a schematic diagram of a network structure to which the embodiment of the present invention is applicable, and as shown in fig. 1, the network structure includes a User terminal (UE) 11, a network side DU12, and a network side CU13, where the User terminal 11 may be a terminal side Device such as a Mobile phone, a Tablet Personal Computer (Tablet Personal Computer), a Laptop Computer (Laptop Computer), a Personal Digital Assistant (PDA), a Mobile Internet Device (MID), or a Wearable Device (Wearable Device), and it should be noted that a specific type of the User terminal 11 is not limited in the embodiment of the present invention. The network-side DU12 and the network-side CU13 may be base stations, for example: macro station, LTE eNB, 5G NR NB, and the like; the network side DU12 and the network side CU13 may also be small stations, such as Low Power Nodes (LPNs), pico, femto, or the like, or the network side DU12 and the network side CU13 may be Access Points (APs), it should be noted that, in this embodiment of the present invention, specific types of the network side DU12 and the network side CU13 are not limited, and the network side DU12 and the network side CU13 may be disposed in the same network side device, or may be disposed in different network side devices that are independent of each other.

For example: taking network-side DU12 and network-side CU13 as gNB-DU and gNB-CU, respectively, for example, as shown in fig. 2, fig. 2 is a schematic diagram of a network structure of a CU-DU separation architecture to which the embodiment of the present invention is applicable. A 5G Core Network (5Next Generation Core, 5GC) and a Next Generation Access Network (NG-RAN) may transmit data through the NG interface. A plurality of 5G base stations (gNB) can exist under the NG-RAN, and data can be transmitted between the gNB through the Xn-C interface. One gNB can comprise a gNB-CU and a plurality of gNB-DUs, data can be transmitted between the gNB-CU and the gNB-DUs through an F1 interface, and one gNB-CU can manage one or more gNB-DUs.

Of course, the network side CU13 may be separated into a CP and a user plane UP, and in this case, reference may be made to fig. 3, where fig. 3 is a schematic diagram of a CU separation architecture according to an embodiment of the present invention. As shown in FIG. 3, one CU-CP may manage multiple CU-UP, and the interface for data transmission between the CU-CP and the CU-UP is the E1 interface. The CU-CP and the CU-UP can interact with the DU, an interface for interaction between the CU-CP and the DU is F1-C, and an interface for interaction between the CU-UP and the DU is F1-U.

Referring to fig. 4, fig. 4 is a flowchart of a method for transmitting uplink small data according to an embodiment of the present invention, and as shown in fig. 4, the method includes the following steps:

401. a network side DU receives an uplink message and uplink small data sent by a target user terminal in an inactive state;

402. the network side DU acquires the context of the target user terminal;

403. the network side DU sends the uplink small data to a network side CU;

404. and the network side DU sends a reply message of the uplink message to the target user terminal.

The target ue may be any ue. The inactive ue may be a ue of the type that is in an inactive state. The uplink message may be an uplink message sent by the target user terminal to the network side device in the random access process, for example: message 3 of the random access procedure (MSG 3). In addition, the uplink message may include some information of the target ue, for example: network capability information, authentication information or identification information of the target user terminal, etc. The uplink small data may be understood as data with a relatively small data quantity, such as a communication message with a small data quantity or a picture with a small data quantity, and preferably, the data with a data quantity smaller than a specific threshold value. Of course, the small data may also be some other data with a smaller data quantity, and the embodiment of the present invention is not limited thereto. The uplink message and the uplink small data sent by the target user terminal may be sent together by one message, or may also be sent by two messages respectively, and the like, which is not limited herein.

In addition, step 402 may be that the network side DU acquires the context of the target ue, if the network side DU retains the context of the ue in the inactive state. After acquiring the context of the target ue, the network side DU may directly send the context of the target ue to the network side CU, so that the F1 signaling procedure is not needed. Of course, if the context is found by the context identifier of the target user terminal, the context identifier of the target user terminal may be a context identifier of the target user terminal that is pre-configured by the network side DU, may be an uplink message that includes the context identifier of the target user terminal, or may be a context identifier that is sent by the target user terminal to the network side DU through another message, and the like, which is not limited in the embodiment of the present invention.

The network side DU may send the uplink small data to the network side CU, and at this time, the network side CU may receive the uplink small data sent by the network side DU, and then may send the uplink small data to the core network. And after the network side DU sends the uplink small data to the network side CU, the network side DU sends a reply message of the uplink message to the target user terminal to complete the transmission process of the uplink small data.

Through the steps, the uplink small data can be sent to the network side DU in the non-activated state before the target user terminal does not enter the connected state, so that the network side DU and the network side CU can quickly process the uplink small data after establishing the context, the data transmission process is simplified, the small data do not need to wait for the target user terminal in the connected state, and the data transmission efficiency is improved.

As an optional implementation manner, if the uplink message includes an MAC CE message, the acquiring, by the network side DU, the context of the target ue includes:

The MAC CE message may be a context Identifier of the target ue, and the context Identifier may be an Inactive Network Temporary Identifier (I-RNTI) or other identifiers. The network side DU searches for the context of the target ue according to the context identifier, which may be the context of the target ue searched from the network side DU under the condition that the network side DU retains the context of the ue in the inactive state. The network side DU can directly obtain the context identifier of the target ue from the MAC CE message, so that the context of the target ue can be searched and obtained according to the context identifier, and corresponding resources can be configured according to the context of the target ue.

As an optional implementation manner, if the uplink message includes an RRC message, the obtaining, by the network side DU, the context of the target ue includes:

The network side DU may send an access request for the target ue to the network side CU, so as to accept a context establishment procedure of the target ue initiated by the network side CU, so as to establish a context of the target ue. In this embodiment, the network side DU can still retain the context of the inactive ue and the context of the target ue.

If the uplink message includes an RRC message, the network side DU cannot decode the RRC message to obtain the context identifier of the target ue, so that the network side CU may send an access request including the RRC message. The network side CU can unlock RRC message, so that information such as the context identifier of the target user terminal can be obtained, and the network side CU can search the context of the target user terminal through the context identifier. After finding the context of the target ue, the network CU may establish context connection with the network DU.

In addition, there are many implementation ways that the network side CU can find the context of the target user terminal through the context identifier. For example: the network side CU may store the context of the target user terminal in advance, so that the context of the target user terminal may be directly found through the context identifier. Or, in a case that the network side CU does not store the context of the target user terminal, the network side CU may obtain the context of the target user terminal from the target base station to which the target user terminal is connected through the context identifier. After the network side CU obtains the context of the target user terminal, it may send the context of the target user terminal to the network side DU. The target base station may be a base station that the target ue last connects to before entering the inactive state, so that the network side CU is configured to obtain a context of the target ue from the base station (e.g., last serving gbb) that the target ue last connects to. Therefore, the context of the target user terminal can be obtained in a plurality of modes, so that when the context of the target user terminal cannot be obtained in a certain mode, the context of the user can be obtained in another mode, and data transmission between the target user terminal and the network side equipment is facilitated.

As an optional implementation manner, if the uplink message includes the RRC message, the reply message of the RRC message is a reply message that the network side DU receives and is sent by the network side CU; or

If the uplink message includes an RRC message, the network side CU may generate a reply message of the RRC message, so that the network side CU may send the reply message to the network side DU, and the network side DU may send the reply message to the target user terminal. If the uplink message includes the MAC CE message, the network side DU may directly generate a reply message of the MAC CE message, so that the reply message may be directly sent to the target user terminal, thereby improving efficiency.

In addition, the reply message may also be referred to as the RRC message or the MAC CE message response message, and the target ue enters a connected state after receiving the reply message, and may perform connected data transmission thereafter.

As an optional implementation manner, in a case that the CP and the UP of the network-side CU are separated, the sending, by the network-side DU, the uplink small data to the network-side CU includes:

the network side DU sends the uplink small data to the UP of the network side CU.

The network side DU sends the uplink small data to the UP of the network side CU, so that the UP of the network side CU can receive the uplink small data of the target User terminal sent by the network side DU, and further send the uplink small data to a User Plane Function (UPF).

Of course, the network side DU may send the uplink small Data to the network side CU, where the network side DU may configure a corresponding Data Radio Bearer (DRB) and a tunnel after receiving the access success response, and then send the uplink small Data to the network side CU or the UP of the network side CU through the DRB and the tunnel.

As an optional implementation manner, if the target ue establishes a connection with the network side DU before entering the inactive state, the network side DU retains the context of the target ue after the target ue accesses the inactive state.

The connection establishment may be that the target ue establishes a connection with the network side DU in a connected state before entering the inactive state, or it may be understood that the connected state of the target ue before entering the inactive state resides under the network side DU. In this case, the network-side CU also retains the context of the target ue. After the target user terminal is accessed to the inactive state, the network side DU can retain the context of the target user terminal, so that when receiving the context identifier of the user, the context of the target user terminal can be quickly found without searching the context of the target user terminal by the network side CU, thereby improving the efficiency of data transmission.

As an optional implementation, the method further comprises:

and the network side DU receives the context establishment process of the target user terminal initiated by the network side CU so as to establish the context of the target user terminal.

There may be various situations when the network side DU fails to acquire the context of the target ue. For example: it may be that the network side DU does not retain any context of the ue, or it may also be that the network side DU retains some contexts of the ue, but does not retain the context of the target ue in the inactive state. Thus, when receiving the uplink small data sent by the target user terminal in the inactive state, the network side DU cannot find the context of the target user terminal according to the context identifier provided by the target user terminal.

Or, the network side DU may also receive the RRC message of the target ue, and the network side DU needs to send the RRC message to the network side CU because the network side DU cannot decode the RRC message to obtain the context identifier of the target ue. The access request may include a context identifier or an RRC message obtained from the MAC CE message. Thus, the network side CU can search the context of the target ue in the inactive state according to the context identifier directly obtained or decoded from the RRC message, thereby establishing the context of the target ue for the network side DU. Then, the network side DU can send the uplink small data of the target ue to the network side CU. When the network side DU cannot resolve the RRC message from the target user terminal, the procedure of accessing the network side DU to the network side CU may be referred to as a procedure of F1 initial access.

It should be noted that, various optional implementations described in the embodiment of the present invention may be implemented in combination with each other, or may be implemented separately, and the embodiment of the present invention is not limited to this.

Thus, in the embodiment of the present invention, a network side DU receives an uplink message and uplink small data sent by a target user terminal in an inactive state; the network side DU acquires the context of the target user terminal; the network side DU sends the uplink small data to a network side CU; and the network side DU sends a reply message of the uplink message to the target user terminal. Compared with the prior art, the embodiment of the invention provides a transmission method of uplink small data, so that the transmission of the uplink small data in an inactive state can be supported under a CU and DU separation architecture. Before the target user terminal does not enter the connected state, the uplink small data can be sent to the network side DU in the non-activated state, so that the uplink small data can be quickly processed, the data transmission process is simplified, the target user terminal in the connected state does not need to wait for the uplink small data, and the data transmission efficiency is improved.

Referring to fig. 5, fig. 5 is a flowchart of a method for transmitting uplink small data according to an embodiment of the present invention, and as shown in fig. 5, the method includes the following steps:

501. and the network side CU receives the uplink small data which are sent by the network side DU and aim at the target user terminal in the non-activated state.

Optionally, the method further includes:

Optionally, when the CP and the UP of the network-side CU are separated, the receiving, by the network-side CU, uplink small data for the target user terminal in the inactive state sent by the network-side DU includes:

Optionally, the method further includes:

It should be noted that, this embodiment is used as an implementation of the network-side CU corresponding to the embodiment shown in fig. 4, and specific implementations thereof may refer to relevant descriptions of the embodiment shown in fig. 4, so that, in order to avoid repeated descriptions, the embodiment is not described again, and the same beneficial effects may also be achieved.

The following describes an uplink small data transmission method provided in the embodiments of the present invention by using multiple embodiments:

example 1:

the network-side CU and the network-side DU may be a gNB-CU and a gNB-DU, respectively. In an inactive state, the gNB-DU retains the context of the UE, and when the gNB-DU receives the uplink small data sent by the UE, the context of the UE can be found according to the UE context identification provided by the UE. It can then be sent directly to the gNB-CU without the F1 signaling procedure.

Referring to fig. 6, fig. 6 is a schematic diagram illustrating transmission of uplink small data according to an embodiment of the present invention. Firstly, UE sends a random access request to gNB-DU, and gNB-DU replies a random access response to UE. Thus, the UE sends the MAC CE message to the gNB-DU and simultaneously sends the uplink small data to the gNB-DU. After receiving the MAC CE message and the uplink small data of the UE, the I-RNTI can be obtained from the MAC CE message, the context of the UE can be searched according to the I-RNTI, and corresponding resources are configured according to the context of the UE. Then, the gNB-DU sends the uplink small data from the UE to the gNB-CU on the corresponding DRB, and the uplink small data is directly sent to the CU UP under the condition of CP UP separation. And then the gNB-CU or the CU UP processes the small uplink data and sends the small uplink data to the UPF. The gNB-DU may reply a response message of the MAC CE message to the UE, and may move the UE to a connection state, thereby further receiving subsequent possible downlink data.

Example 2:

referring to fig. 7, fig. 7 is a schematic diagram illustrating transmission of uplink small data according to an embodiment of the present invention. If the gNB-DU does not find the context of the UE in the stored UE context according to the context identifier provided by the UE, or the gNB-DU does not release the RRC message, the context of the UE can be obtained by the method in this embodiment. Firstly, UE sends a random access request to gNB-DU, and gNB-DU replies a random access response to UE. Therefore, the UE sends the RRC message or the MAC CE message to the gNB-DU and simultaneously sends the uplink small data to the gNB-DU. After receiving the RRC message or MAC CE message of the UE and the uplink small data, the gNB-DU may initiate an access procedure to the gNB-CU, and send the content of the RRC message or MAC CE message (especially the UE context identifier, such as I-RNTI) to the gNB-CU through F1 signaling.

The F1 signaling is signaling sent by the gNB-DU and the gNB-CU through an F1 interface. And the gNB-CU searches the context of the UE according to the I-RNTI and replies an access request of the gNB-DU. And if the gNB-CU does not store the context of the UE, the gNB-CU initiates a context acquisition process to the old serving base station according to the I-RNTI, and after taking the UE context, the gNB-CU establishes the UE context with the gNB-DU and then notifies the gNB-DU of the access response.

In addition, under the condition of CP UP separation, after receiving an RRC message or an MAC CE message of the UE and uplink small data, the gNB-DU may initiate an access procedure to the CU CP; the CU CP will address the UE context based on the UE context identity (such as I-RNTI); the CU CP establishes UE context with the gNB-DU and then informs the gNB-DU of the access response. And after receiving the access success response, the gNB-DU configures corresponding DRBs and tunnels, and then sends data to the gNB-CU or CU UP. The gNB-DU replies the result of the RRC message or the MAC CE message to the UE. And the UE may be switched to the connected state or to the inactive state. And at this time, the gNB-CU may perform uplink data response or downlink data transmission, and the gNB-CU may also perform uplink data response or downlink data transmission.

Example 3:

in this embodiment, the UE accesses the network through the RRC message and simultaneously transmits small data.

The gNB-DU needs to initiate an initial access process to the gNB-CU, because the gNB-DU can not know the context identifier of the UE without opening the RRC message.

Step 1, a gNB-DU receives RRC message and uplink small data of a certain UE in an inactive state;

step 2, the gNB-DU transmits the message to the gNB-CU;

step 3, the gNB-CU decodes the RRC message to obtain information such as UE context identification, and the gNB-CU searches the UE context according to the UE context identification, wherein the following two conditions exist:

case 1: the gNB-CU stores the context of the UE, then the gNB-CU initiates a context establishment process to the gNB-DU, and sends an RRC message to the UE to respond to a request message of the UE after the establishment is successful (the message is sent to the UE through the gNB-DU);

case 2: if the gNB-CU does not store the context of the UE, the gNB-CU finds the old serving base station to acquire the context of the UE according to the context identifier of the UE, and the flow after the acquisition is successful is the same as the above.

And step 4, after the UE context is successfully established on an F1 interface (interface between the gNB-DU and the gNB-CU), the gNB-DU can send the uplink small data from the UE to the gNB-CU.

In this embodiment, the gNB-DU cannot know the context identifier of the UE because it cannot parse the RRC message. And the gNB-DU sends the RRC message to the gNB-CU, and the gNB-CU can decode the RRC message so as to acquire the context identification of the UE and search the context of the UE.

Example 4:

in this embodiment, it is specifically described that the UE accesses the network through the MAC CE message and simultaneously transmits small data, and the gNB-DU retains the context of the UE.

The gNB-CU and the gNB-DU both retain the context of the UE, and the gNB-DU can directly transmit the data of the UE to the gNB-CU on the corresponding DRB.

Step 1, a gNB-DU receives MAC CE information and uplink small data of a certain UE in an inactive state;

step 2, the gNB-DU acquires the context identifier of the UE from the MAC CE message, such as I-RNTI, and the gNB-DU finds the context of the UE according to the context identifier of the UE;

step 3, the gNB-DU sends the uplink small Data from the UE to the gNB-CU by using the configuration in the stored UE context, and then a Packet Data Convergence Protocol (PDCP) entity of the gNB-CU processes the corresponding Data and sends the Data to the UPF;

and step 4, the gNB-DU replies a MAC CE response message to the UE.

Since the gNB-DU reserves the context of the UE, the context of the UE can be directly searched from the gNB-CU without searching the context of the UE by the gNB-CU.

Example 5:

the UE accesses the network through the MAC CE message and simultaneously transmits small data, and the gNB-DU does not reserve the context of the UE.

If the gNB-DU does not store the UE context or the gNB-DU stores the UE context, but the gNB-DU does not have the context of the UE, the procedures of F1 such as access and context establishment are needed.

Step 1, a gNB-DU receives MAC CE information and uplink small data of a certain non-activated UE;

step 2, the gNB-DU acquires the context identifier of the UE from the MAC CE message, such as I-RNTI, and the gNB-DU does not store the UE context or cannot obtain the UE context according to the UE context identifier;

step 3, the gNB-DU initiates an initial access process to the gNB-CU, and the message at least contains UE context identification, such as I-RNTI;

and step 4, the gNB-CU searches for the UE context according to the UE context identifier, and if the gNB-CU does not store the UE context, the gNB-CU initiates a process of obtaining the UE context to the old service base station according to the UE context identifier.

And step 5, after the gNB-CU obtains the context of the UE, the gNB-CU initiates a UE context establishment process to the gNB-DU.

And 6, after the UE context is successfully established on the F1 interface, the gNB-DU can send the uplink small data of the UE to the gNB-CU on the corresponding DRB.

And 7, after the UE context on the F1 interface is successfully established, the gNB-CU replies a response of successful access to the gNB-DU.

And step 8, the gNB-DU replies a response message of the MAC CE message to the UE.

Since the gNB-DU retains the context of the UE, the context of the UE needs to be looked up by the gNB-CU.

For the interaction between the gNB-DU and the gNB-CU, reference may be made to the foregoing embodiments, which are not described herein again.

Referring to fig. 8, fig. 8 is a structural diagram of a network side DU according to an embodiment of the present invention, and as shown in fig. 8, a network side DU800 includes:

a receiving module 801, configured to receive an uplink message and uplink small data sent by a target user terminal in an inactive state;

an obtaining module 802, configured to obtain a context of the target user terminal;

a first sending module 803, configured to send the uplink small data to a network-side CU;

a second sending module 804, configured to send a reply message of the uplink message to the target user terminal.

Optionally, if the uplink message includes an MAC CE message, as shown in fig. 9, the obtaining module 802 includes:

an obtaining unit 8021, configured to obtain a context identifier of the target ue from the MAC CE message;

a searching unit 8022, configured to search for and obtain the context of the target user terminal according to the context identifier.

Optionally, if the uplink message includes an RRC message, as shown in fig. 10, the obtaining module 802 includes:

a sending unit 8023, configured to send, to the network side CU, an access request for the target user terminal when the uplink message includes the RRC message, where the access request includes the RRC message;

an accepting unit 8024, configured to accept a context establishment procedure of the target user terminal initiated by the network side CU, so as to establish a context of the target user terminal.

Optionally, in a case that the CP and the UP of the network-side CU are separated, the first sending module 803 is configured to send the uplink small data to the UP of the network-side CU.

Optionally, if the target ue establishes a connection with the network side DU800 before entering the inactive state, the network side DU800 reserves the context of the target ue after the target ue accesses the inactive state.

Optionally, as shown in fig. 11, the network side DU800 further includes:

a third sending module 805, configured to send, to the network CU, an access request for the target ue if the network DU fails to acquire the context of the target ue;

an accepting module 806, configured to accept a context establishment procedure of the target user terminal initiated by the network side CU, so as to establish a context of the target user terminal.

It should be noted that, in this embodiment, the network side DU800 may be a network side DU according to any implementation manner in the method embodiment of the present invention, and any implementation manner of the network side DU in the method embodiment of the present invention may be implemented by the network side DU800 in this embodiment, and the same beneficial effects are achieved, and details are not described here.

Referring to fig. 12, fig. 12 is a structural diagram of a network-side CU according to an embodiment of the present invention, and as shown in fig. 12, a network-side CU1200 includes:

a first receiving module 1201, configured to receive uplink small data, which is sent by a network side DU and is for a target ue in an inactive state.

Optionally, as shown in fig. 13, the network-side CU1200 further includes:

a second receiving module 1202, configured to receive an access request of the target user terminal sent by the network side DU, where the access request includes an RRC message of the target user terminal;

a first obtaining module 1203, configured to obtain a context identifier of the target ue from the RRC message;

a second obtaining module 1204, configured to obtain a context of the target user terminal according to the context identifier;

a first initiating module 1205 is configured to initiate, by the network side CU, a context establishment procedure of the target user terminal to the network side DU.

Optionally, the first obtaining module 1203 is configured to obtain, according to the context identifier, a context of the target user terminal, where the context is pre-stored by the network side CU; or under the condition that the network side CU does not store the context of the target user terminal, acquiring the context of the target user terminal from a target base station connected with the target user terminal according to the context identifier.

Optionally, under the condition that the CP and the UP of the network-side CU are separated, the first receiving module 1201 is configured to receive, by the UP of the network-side CU, uplink small data, which is sent by the network-side DU and is addressed to the target user terminal in the inactive state, by the UP of the network-side CU.

Optionally, as shown in fig. 14, the network-side CU1200 further includes:

a third receiving module 1206, configured to receive an access request for the target ue sent by the network side DU;

a second initiating module 1207, configured to initiate a context establishment procedure of the target ue to the network side DU.

It should be noted that, in this embodiment, the network-side CU1200 may be a network-side CU according to any implementation manner in the method embodiment of the present invention, and any implementation manner of the network-side CU in the method embodiment of the present invention may be implemented by the network-side CU1200 in this embodiment, so as to achieve the same beneficial effects, and details are not described here again.

Referring to fig. 15, fig. 15 is a structural diagram of another network-side DU according to an embodiment of the present invention, and as shown in fig. 15, the network-side DU includes: a transceiver 1510, a memory 1520, a processor 1500, and a computer program stored on the memory 1520 and executable on the processor, wherein:

the transceiver 1510 is configured to receive an uplink message and uplink small data sent by a target user equipment in an inactive state;

the processor 1500 is configured to obtain a context of the target ue;

the transceiver 1510 is configured to send the uplink small data to a network CU;

the transceiver 1510 is configured to send a reply message of the uplink message to the target ue.

The transceiver 1510, among other things, may be used to receive and transmit data under the control of the processor 1500.

In fig. 15, the bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 1500 and various circuits of memory represented by memory 1520 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1510 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium.

The processor 1500 is responsible for managing the bus architecture and general processing, and the memory 1520 may store data used by the processor 1500 in performing operations.

It should be noted that the memory 1520 is not limited to be on the network side DU, and the memory 1520 and the processor 1500 may be separated and located in different geographical locations.

sending an access request aiming at the target user terminal to the CU under the condition that the uplink message comprises the RRC message, wherein the access request comprises the RRC message;

Optionally, if the uplink message includes the RRC message, the reply message of the RRC message is a reply message that the network side DU receives and is sent by the network side CU; or alternatively

and sending the uplink small data to UP of the network side CU.

Optionally, the transceiver 1510 is further configured to send an access request for the target ue to the network CU if the network DU fails to acquire the context of the target ue; and receiving the context establishing process of the target user terminal initiated by the CU at the network side so as to establish the context of the target user terminal.

It should be noted that, in this embodiment, the network side DU may be a network side DU implemented in any embodiment of the method embodiment in the present invention, and any embodiment of the network side DU in the method embodiment in the present invention may be implemented by the network side DU in this embodiment to achieve the same beneficial effects, which is not described herein again.

Referring to fig. 16, fig. 16 is a block diagram of another network-side CU according to an embodiment of the present invention, and as shown in fig. 16, the network-side CU includes: a transceiver 1610, a memory 1620, a processor 1600, and a computer program stored on the memory 1620 and executable on the processor, wherein:

the transceiver 1610 is configured to receive uplink small data, which is sent by a network side DU and is for a target ue in an inactive state.

The transceiver 1610 may be used for receiving and transmitting data under the control of the processor 1600, among other things.

In fig. 16, the bus architecture may include any number of interconnected buses and bridges, with various circuits being linked together, in particular, one or more processors represented by a processor 1600 and a memory represented by a memory 1620. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1610 can be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium.

The processor 1600 is responsible for managing the bus architecture and general processing, and the memory 1620 may store data used by the processor 1600 in performing operations.

It should be noted that the memory 1620 is not limited to be on the network side CU, and the memory 1620 and the processor 1600 may be separated in different geographical locations.

Optionally, the transceiver 1610 is further configured to: receiving an access request of the target user terminal sent by the network side DU, wherein the access request comprises an RRC message of the target user terminal;

the processor 1600 is further configured to obtain a context identifier of the target ue from the RRC message;

the processor 1600 is further configured to obtain a context of the target user terminal according to the context identifier;

the transceiver 1610 is further configured to initiate a context establishment procedure of the target ue to the network side DU.

Optionally, the transceiver 1610 is further configured to: receiving an access request aiming at the target user terminal sent by the network side DU; and initiating a context establishing process of the target user terminal to the network side DU.

It should be noted that, in this embodiment, the network-side CU may be a network-side CU according to any implementation manner in the method embodiment in the embodiment of the present invention, and any implementation manner of the network-side CU in the method embodiment in the embodiment of the present invention may be implemented by the network-side CU in this embodiment, so as to achieve the same beneficial effects, and details are not described here again.

In the several embodiments provided in the present application, it should be understood that the disclosed method and apparatus may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be physically included alone, or two or more units may be integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

The integrated unit implemented in the form of a software functional unit may be stored in a computer readable storage medium. The software functional unit is stored in a storage medium and includes several instructions to enable a computer device (which may be a personal computer, a server, or a network device) to execute some steps of the transceiving method according to various embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

Claims

1. A method for transmitting uplink small data is characterized by comprising the following steps:

a network side distributed unit DU receives an uplink message and uplink small data sent by a target user terminal in an inactive state;

the network side DU acquires the context of the target user terminal;

the network side DU sends the uplink small data to a network side centralized unit CU;

the network side DU sends a reply message of the uplink message to the target user terminal;

if the uplink message includes a radio resource control RRC message, the obtaining, by the network side DU, the context of the target ue includes:

the network side DU receives a context establishing process of the target user terminal initiated by the network side CU to establish a context of the target user terminal;

if the target user terminal establishes connection with the network side DU before entering the inactive state, the network side DU retains the context of the target user terminal after the target user terminal accesses the inactive state.

2. The method of claim 1,

if the uplink message includes the RRC message, the reply message of the RRC message is a reply message that the network side DU receives and is sent by the network side CU.

3. The method as claimed in claim 1, wherein the sending of the upstream small data by the network-side DU to the network-side CU with separation of a control plane CP and a user plane UP of the network-side CU comprises:

4. The method of claim 1, wherein the method further comprises:

the network side DU receives a context establishment procedure of the target ue initiated by the network side CU to establish a context of the target ue.

5. A method for transmitting uplink small data is characterized by comprising the following steps:

a network side CU receives uplink small data which are sent by a network side DU and aim at a target user terminal in an inactive state; the CU at the network side receives an access request of the target user terminal sent by the DU at the network side, wherein the access request comprises an RRC message of the target user terminal;

the CU initiates a context establishment process of the target user terminal to the DU;

6. The method as claimed in claim 5, wherein the network side CU obtaining the context of the target ue according to the context identifier includes:

7. The method according to any of claims 5 to 6, wherein the receiving, by the network-side CU, the uplink small data for the target user terminal in the inactive state sent by the network-side DU with the CP and UP of the network-side CU separated comprises:

8. A network-side DU, comprising:

the receiving module is used for receiving uplink messages and uplink small data sent by the target user terminal in the non-activated state;

a second sending module, configured to send a reply message of the uplink message to the target user terminal;

if the uplink message includes an RRC message, the obtaining module includes:

a sending unit, configured to send, to the CU on the network side, an access request for the target user terminal when the uplink message includes the RRC message, where the access request includes the RRC message;

a receiving unit, configured to receive a context establishment procedure of the target user terminal initiated by the network side CU, so as to establish a context of the target user terminal;

9. A network-side CU, comprising:

the receiving module is used for receiving uplink small data which are sent by a network side DU and aim at a target user terminal in an inactive state;

a second receiving module, configured to receive an access request of the target user equipment sent by the network side DU, where the access request includes an RRC message of the target user equipment;

a first obtaining module, configured to obtain a context identifier of the target ue from the RRC message;

a second obtaining module, configured to obtain a context of the target user terminal according to the context identifier;

a first initiating module, configured to initiate, by the network side CU, a context establishment procedure of the target user terminal to the network side DU;

10. A network-side DU, comprising: a transceiver, a memory, a processor, and a computer program stored on the memory and executable on the processor,

the processor is configured to obtain a context of the target user terminal;

the transceiver is used for sending the uplink small data to a network side CU;

the transceiver is configured to send a reply message of the uplink message to the target user terminal;

if the uplink message includes an RRC message, the obtaining the context of the target ue includes:

receiving a context establishing process of the target user terminal initiated by the CU at the network side so as to establish the context of the target user terminal;

11. The network-side DU according to claim 10 wherein,

12. The network side DU of claim 10, wherein the sending the upstream small data to the network-side CU with the CP and UP of the network-side CU separated comprises:

and sending the uplink small data to UP of the network side CU.

13. A network-side CU, comprising: a transceiver, a memory, a processor, and a computer program stored on the memory and executable on the processor,

the transceiver is used for receiving uplink small data which are sent by a network side DU and aim at a target user terminal in an inactive state;

the transceiver is further configured to: receiving an access request of the target user terminal sent by the network side DU, wherein the access request comprises an RRC message of the target user terminal;

the transceiver is further configured to initiate a context establishment procedure of the target user terminal to the network side DU;

14. The CU of claim 13, wherein said obtaining the context of the target ue according to the context identifier comprises:

15. The network-side CU according to any of claims 13 to 14, wherein the receiving the uplink small data for the target ue in the inactive state sent by the network-side DU with the CP and UP of the network-side CU separated comprises:

16. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps in the transmission method of upstream small data according to any one of claims 1 to 4, or which, when being executed by a processor, carries out the steps in the transmission method of upstream small data according to any one of claims 5 to 7.