CN113271687A

CN113271687A - Data transmission method, service base station and anchor point base station

Info

Publication number: CN113271687A
Application number: CN202010096892.5A
Authority: CN
Inventors: 孙建成; 梁靖
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2020-02-17
Filing date: 2020-02-17
Publication date: 2021-08-17
Anticipated expiration: 2040-02-17
Also published as: CN113271687B

Abstract

The embodiment of the invention provides a data transmission method, a service base station and an anchor point base station, wherein the method comprises the following steps: when receiving an RRC recovery request message sent by a terminal in a Radio Resource Control (RRC) non-activated state, sending a first context acquisition request message to an anchor point base station; the first context acquiring request message only carries an uplink data packet, or carries the uplink data packet and auxiliary information, and the auxiliary information is used for indicating data to be transmitted; and receiving an indication message fed back by the anchor base station based on the information carried in the first context acquiring request message, wherein the indication message is used for indicating whether the terminal reenters an RRC (radio resource control) inactive state. The embodiment of the invention avoids the context transfer process in the terminal data transmission process in the non-activated state and reduces the service delay.

Description

Data transmission method, service base station and anchor point base station

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a data transmission method, a serving base station, and an anchor base station.

Background

A New Radio Resource Control (RRC) state is defined in the New Radio (NR) network: RRC Inactive (Inactive) state. A node in the radio access network may send an RRC Release message carrying suspend configuration (SuspendConfig) to a terminal in an RRC connected state to indicate that it enters an RRC inactive state. And the node is the anchor node of the terminal and reserves the context information of the terminal. The RRC Release message further includes radio access network Notification Area (RNA) configuration information, and the terminal does not need to communicate with the network side when moving within the configured RNA range.

During this time, the terminal and the network side may need to briefly interact with a small amount of user data. According to the prior art, no matter what kind of data is interacted, the anchor node needs to move the context information of the terminal to the base station where the terminal is currently located, namely the context transfer process. According to the requirement of the core network, the context transfer process is necessarily accompanied with a path switching process to change the user data path between the access network and the core network. The user data can be transmitted to the receiving end after both processes are completed. The context transfer process may be cumbersome, and the data plane establishment delay is long, which is not convenient for implementing small data volume transmission in the RRC inactive state.

In summary, in the prior art, when a terminal is in an RRC inactive state and has a small amount of data to transmit, there are problems of cumbersome operation and long time delay.

Disclosure of Invention

The embodiment of the invention provides a data transmission method, a service base station and an anchor point base station, which are used for reducing service time delay when a terminal in an RRC (radio resource control) non-activated state transmits a small amount of data.

The embodiment of the invention provides a data transmission method, which is applied to a service base station and comprises the following steps:

when receiving an RRC recovery request message sent by a terminal in a Radio Resource Control (RRC) non-activated state, sending a first context acquisition request message to an anchor point base station; the first context acquiring request message only carries an uplink data packet, or carries the uplink data packet and auxiliary information, and the auxiliary information is used for indicating data to be transmitted;

and receiving an indication message fed back by the anchor base station based on the information carried in the first context acquiring request message, wherein the indication message is used for indicating whether the terminal reenters an RRC (radio resource control) inactive state.

The embodiment of the invention provides a data transmission method, which is applied to an anchor point base station and comprises the following steps:

receiving a first context acquiring request message sent by a serving base station, wherein the first context acquiring request message is sent when the serving base station receives an RRC recovery request message sent by a terminal in an RRC (radio resource control) inactive state, and the first context acquiring request message only carries an uplink data packet or carries the uplink data packet and auxiliary information, and the auxiliary information is used for indicating data to be transmitted;

and sending an indication message to the serving base station based on the information carried in the first context acquiring request message, wherein the indication message is used for indicating whether the terminal reenters an RRC (radio resource control) inactive state.

The embodiment of the invention provides a data transmission device, which is applied to a service base station and comprises the following components:

the transmission module is used for transmitting a first context acquisition request message to an anchor point base station when receiving an RRC recovery request message transmitted by a terminal in a Radio Resource Control (RRC) inactive state; the first context acquiring request message only carries an uplink data packet, or carries the uplink data packet and auxiliary information, and the auxiliary information is used for indicating data to be transmitted;

a receiving module, configured to receive an indication message fed back by the anchor base station based on information carried in the first context request obtaining message, where the indication message is used to indicate whether the terminal reenters an RRC inactive state.

The embodiment of the invention provides a data transmission device, which is applied to an anchor point base station and comprises the following components:

a receiving module, configured to receive a first context acquiring request message sent by a serving base station, where the first context acquiring request message is sent by the serving base station when receiving an RRC recovery request message sent by a terminal in an RRC inactive state of radio resource control, and the first context acquiring request message only carries an uplink data packet or carries an uplink data packet and auxiliary information, where the auxiliary information is used to indicate data to be transmitted;

a sending module, configured to send an indication message to the serving base station based on information carried in the first context request obtaining message, where the indication message is used to indicate whether the terminal reenters an RRC inactive state.

The embodiment of the invention provides a service base station, which comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the processor realizes the steps of the service base station side data transmission method when executing the program.

The embodiment of the invention provides an anchor point base station, which comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the processor executes the program to realize the steps of the anchor point base station side data transmission method.

An embodiment of the present invention provides a non-transitory computer-readable storage medium, on which a computer program is stored, which, when executed by a processor, implements the steps of the data transmission method.

According to the data transmission method, the service base station and the anchor base station provided by the embodiment of the invention, when an RRC recovery request sent by a terminal in an RRC inactive state is received, a first context acquisition request message is sent to the anchor base station, and an indication message of whether the anchor base station reenters the RRC inactive state based on information feedback carried in the first context acquisition request message is received, so that whether the terminal performs anchor transfer or not is selected, the problem that the anchor transfer is required only when the data is transmitted by the terminal in the inactive state in the prior art is solved, the complicated processes of context transfer and path transfer in the anchor transfer process are avoided, the signaling cost is saved, and the service time delay is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

Fig. 1 is a flowchart illustrating steps of a data transmission method applied to a serving base station according to an embodiment of the present invention;

fig. 2 is a flowchart illustrating steps of a data transmission method applied to an anchor base station according to an embodiment of the present invention;

FIG. 3 is a flowchart illustrating an overall data transmission method according to an embodiment of the present invention;

FIG. 4 is a second flowchart illustrating an overall data transmission method according to an embodiment of the present invention;

FIG. 5 is a third flowchart illustrating an overall data transmission method according to an embodiment of the present invention;

FIG. 6 is a fourth flowchart illustrating an overall data transmission method according to an embodiment of the present invention;

FIG. 7 is a fifth flowchart illustrating an overall data transmission method according to an embodiment of the present invention;

fig. 8 is a block diagram of a data transmission apparatus applied to a serving base station according to an embodiment of the present invention;

fig. 9 is a block diagram of a data transmission apparatus applied to an anchor base station in an embodiment of the present invention;

fig. 10 is a schematic structural diagram of a serving base station according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of an anchor base station in an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

When the terminal enters the RRC inactive state, the anchor base station configures an RNA for the terminal. The terminal can learn whether it is currently within the configured RNA range by broadcasting. Once the terminal finds that the cell in which it resides does not belong to the configured RNA, the terminal typically initiates an RNA update (RNAU) procedure to re-request a new RNA from the network side to ensure that the radio access network can still find the terminal by means of paging.

If the terminal or the network side needs to send data or needs to execute the RNAU procedure, the terminal triggers the RRC connection recovery procedure. On this premise, if the node of the cell where the terminal is currently located is different from the anchor base station, the radio access network will perform a context transfer procedure inside, and after the context transfer procedure is completed, the radio access network needs to perform a path switching procedure with the core network before user data can be transmitted.

That is, when a terminal in an RRC inactive state has a small amount of data to send, the anchor base station needs to move the context information of the terminal to a base station (serving base station) where the terminal is currently located, which is a context transfer process. The path switching process is required to be executed after the context transfer process is completed, and the user plane data can be sent to the receiving end only after the two processes are completed, so that the operation is complicated, the time delay is long, and the small data volume transmission in the RRC inactive state is not convenient to realize. To this end, the invention provides the following examples:

as shown in fig. 1, a flowchart of steps of a data transmission method applied to a serving base station in the embodiment of the present invention is shown, where the method includes the following steps:

step 101: when receiving an RRC recovery request message sent by a terminal in an RRC non-activated state, sending a first context acquisition request message to an anchor base station.

Specifically, when the terminal in the RRC inactive state and moving to another serving base station different from the anchor base station needs to transmit uplink data, the terminal may send an RRC recovery Request to the serving base station, that is, the terminal may send the uplink data to the serving base station through an RRC recovery Request (RRC Resume Request) procedure in the inactive state.

In addition, specifically, when the serving base station receives the RRC recovery request, a first get context request message may be sent to the anchor base station to request to get the context of the terminal.

In addition, it should be noted that the first get context request message only carries the uplink data packet, or carries the uplink data packet and the auxiliary information, where the auxiliary information is used to indicate data to be transmitted. In addition, it should be noted that, only carrying the uplink data packet is for whether or not to carry the auxiliary information, that is, it can be understood that the first acquisition context request message carries the uplink data packet but does not carry the auxiliary information.

Of course, both the uplink data packet and the auxiliary information are sent to the serving base station by the terminal.

Specifically, the uplink data packet may be a medium access control protocol data unit (MAC PDU) from one or more data radio bearers (DRBs for short). That is, the serving base station may carry the uplink data packet in the first acquisition context request message in the form of MAC PDU and send the uplink data packet to the anchor base station.

Step 102: and receiving an indication message fed back by the anchor point base station based on the information carried in the first context obtaining request message.

Specifically, the information carried in the first context acquiring request message may be only an uplink data packet carried, or may also be an uplink data packet and auxiliary information carried simultaneously.

Specifically, the indication message is used to indicate whether the terminal re-enters the RRC inactive state, that is, whether anchor transfer is to be performed or not can be indicated, so that a process that in the prior art, the anchor transfer is required only when the terminal in the inactive state has data transmission, that is, context transfer and path transfer are performed is avoided, signaling overhead is saved, and service delay is reduced.

In this way, the serving base station in this embodiment sends the first context acquisition request message to the anchor base station when receiving the RRC recovery request sent by the terminal in the RRC inactive state, and receives the indication message that the anchor base station feeds back whether the terminal enters the RRC inactive state again based on the information carried in the first context acquisition request message, so as to implement selection of whether the terminal performs anchor transfer, thereby avoiding a problem that the terminal in the inactive state in the prior art needs anchor transfer as long as there is data transmission, avoiding cumbersome processes of context transfer and path transfer in the anchor transfer process, saving signaling overhead, and reducing service delay.

Furthermore, it should be noted that the auxiliary information may indicate at least one of the following: the reason value, whether the terminal has a subsequent uplink data packet to be sent, the data volume of the subsequent uplink data packet to be sent, and whether the terminal has an expected downlink data packet. Thereby enabling an indication of the auxiliary information to the data that needs to be transmitted.

Further, a process of the serving base station receiving the indication message fed back by the anchor base station based on the information carried in the first acquisition context request message is described herein.

The first method comprises the following steps: when the first context acquiring request message only carries the uplink data packet, that is, when the first context acquiring request message does not carry the auxiliary information:

at this time, when receiving the indication message fed back by the anchor base station based on the information carried in the first context acquisition request message, the serving base station may receive a context acquisition failure message fed back by the anchor base station.

Specifically, the context acquisition failure message carries an RRC release message indicating that the terminal re-enters the RRC inactive state.

That is, when the terminal sends uplink data to the network through the RRC recovery request procedure in the inactive state and the terminal does not provide any auxiliary information (e.g., a cause value of the duplicate MO data class), the serving base station may include user data (MAC PDU from one or more DRBs) in the first acquisition context request message and send the user data to the anchor base station (without additional indication information or a special cause value). Specifically, after receiving the first context acquiring request message, the anchor base station processes the user data therein and sends the user data to the core network; in addition, the anchor base station determines the subsequent state of the terminal, that is, for the first context acquisition request message carrying the uplink data packet of the terminal, the anchor base station may choose not to perform anchor transfer, so that an acquisition context failure message may be replied to the serving base station, and the acquisition context failure message includes an RRC Release (Release) message indicating that the terminal returns to the inactive state again.

Of course, it should be noted herein that when the uplink data packet adopts the RLC AM mode, the acquisition context failure message also carries an RLC ACK corresponding to the uplink data packet.

At this time, specifically, the RLC ACK includes an ACK of the RLC layer and a logical channel identifier corresponding to the uplink data packet; alternatively, the RLC ACK is carried in a medium access control protocol data unit (MAC PDU). That is, the anchor base station may directly feed back the RLC ACK and the logical channel identifier of the uplink data packet to the serving base station, or the anchor base station may process the RLC ACK of the uplink data packet to be changed into an MAC PDU and then feed back the MAC PDU to the serving base station. Then, the serving base station may transmit RLC ACK and RRC release message to the terminal.

In addition, the number of RLC ACKs may be one or more, which depends on the number of DRBs in RLC AM mode for uplink data transmission, and is not limited herein.

Of course, if the terminal subsequently has an uplink data packet to send, the above process may be repeated.

Thus, in the embodiment, the service base station receives the failure message of acquiring the context fed back by the anchor base station, thereby realizing that the anchor transfer is not performed, avoiding the complicated context transfer and path transfer process in the anchor transfer process, and reducing the service delay.

And the second method comprises the following steps: specifically, in consideration of different service characteristics of the terminal, there may be multiple consecutive uplink data and/or expected downlink data to be transmitted, so the air interface may add auxiliary information, for example, a new cause value, and also, for example, a new indication (indicating whether there is a subsequent uplink data packet or an expected downlink data packet) in the RRC recovery request message. At this time, on the Xn interface, while the serving base station sends the data to the anchor base station, the serving base station may also transmit the cause value, whether there is a subsequent uplink data packet indication (or how much subsequent data amount is in the buffer according to the buffer status report indication), whether there is an expected downlink data packet, and the like, to the anchor base station.

At this time, when the first context acquiring request message carries the uplink data packet and the auxiliary information:

when the serving base station receives the indication message fed back by the anchor base station based on the information carried in the first context request obtaining message, the indication message may include any one of the following:

first, when the auxiliary information indicates that the terminal has no subsequent uplink data packet to be sent and no expected downlink data packet, the receiving anchor base station receives a context acquisition failure message fed back when the downlink data packet for the terminal is not received.

That is, in this process, if the terminal has no subsequent uplink data packet to be sent, and also has no desired downlink data packet, and the anchor base station has not received a downlink data packet for the terminal from the core network node, the anchor base station may select to continue to maintain the context of the terminal to perform NG connection with the terminal, that is, no anchor transfer is performed. At this time, the anchor base station generates an RRC release message and feeds back the RRC release message to the serving base station, where the RRC release message indicates that the terminal returns to the RRC inactive state again.

Of course, if the uplink data packet adopts the RLC AM mode, the context failure information is also obtained and the RLC ACK corresponding to the uplink data packet is carried. At this time, specifically, the RLC ACK includes an ACK of the RLC layer and a logical channel identifier corresponding to the uplink data packet; alternatively, the RLC ACK is carried in a medium access control protocol data unit (MAC PDU).

It should be noted that, in this embodiment, the relevant content of the RLC ACK may refer to the relevant content in the above embodiment, and is not described herein again.

Therefore, the terminal does not perform the anchor point transfer process, thereby avoiding the complex context transfer and path transfer process and reducing the service delay.

And secondly, receiving the context acquiring response message fed back by the anchor base station when the auxiliary information indicates that the terminal has the expected downlink data packet and/or the anchor base station receives the downlink data packet aiming at the terminal.

Specifically, the context acquisition response message indicates that the terminal enters the RRC connected state.

That is, in the process, if the terminal indicates that there is an expected downlink data packet and/or the anchor base station receives a data packet sent by the core network node, the anchor base station selects to perform anchor transfer, and feeds back an acquisition context response message (including the terminal context) to the serving base station. And then the service base station subsequently completes the restoration of the air interface and the path conversion process of the NG interface, so that the terminal enters a connection state. At this time, the downlink data of the terminal may be sent to the terminal in a connected state.

Of course, when the uplink data packet adopts the RLC AM mode, the context acquisition response message also carries the RLC ACK corresponding to the uplink data packet. At this time, specifically, the RLC ACK includes an ACK of the RLC layer and a logical channel identifier corresponding to the uplink data packet; alternatively, the RLC ACK is carried in the MAC PDU.

And thirdly: when the auxiliary information indicates that the terminal has a subsequent uplink data packet to be sent and does not have an expected downlink data packet, any one of the following manners may be adopted:

1) and receiving a context acquisition failure message fed back by the anchor base station after the uplink data packet carried in the first context acquisition request message is sent to the core network node, continuing to send a second context acquisition request message to the anchor base station, and receiving a context acquisition failure message fed back by the anchor base station after the uplink data packet carried in the second context acquisition request message is sent to the core network node until the subsequent uplink data packet to be sent is sent completely.

Specifically, the second context acquiring request message carries the uplink data packet and the auxiliary information, and the context acquiring failure message carries an RRC release message indicating that the terminal reenters the RRC inactive state.

That is, in this process, when the auxiliary information indicates that the terminal has a subsequent uplink data packet to be sent and there is no desired downlink data packet, the anchor base station may normally send the uplink data packet carried in the first context acquisition request message, that is, the first uplink data packet, to the core network node, and then the anchor base station may send a context acquisition failure message to the serving base station after sending the first uplink data packet, so that the terminal returns to the RRC inactive state. Then, the subsequent uplink data packet to be sent is sent to the anchor base station by adopting the same flow, namely, the terminal continues to send an RRC recovery request message to the serving base station, the serving base station continues to send a second context acquisition request message to the anchor base station, and receives a context acquisition failure message fed back by the anchor base station after sending the uplink data packet carried in the second context acquisition request message to the core network node; and repeating the process until the subsequent uplink data packet to be sent is sent completely.

Of course, it should be noted herein that the information carried in the RRC recovery request message that the terminal continues to send to the serving base station is the same as the information carried in the second get context request message.

Therefore, the terminal does not perform the anchor point transfer process, thereby avoiding the complex context transfer and path transfer process.

2) And the service base station continuously sends at least one third context acquisition request message to the anchor base station and receives a context acquisition failure message fed back when the auxiliary information in the third context acquisition request message of the anchor base station indicates that the terminal has no subsequent uplink data packet to be sent and no expected downlink data packet.

Specifically, the third acquisition context request message carries the uplink data packet and the auxiliary information.

That is, in this process, when the auxiliary information indicates that the terminal has a subsequent uplink data packet to be sent and does not have an expected downlink data packet, after the serving base station sends the first acquisition context request message to the anchor base station, the anchor base station may not immediately respond to the first acquisition context request message of the terminal (wait for subsequent uplink data), and of course, the serving base station does not wait for the indication message sent by the anchor base station, but continues to receive the user data that is sent again by the terminal through the air interface. At this time, the serving base station continues to send a third context acquisition request message to the anchor base station, wherein the third context acquisition request message carries an uplink data packet which is sent again by the terminal, so that the user data which is sent again is sent to the anchor base station; in addition, the third context acquiring request message may also carry auxiliary information to continuously indicate whether there is a subsequent uplink data packet to be sent and/or an expected downlink data packet; when there is a subsequent uplink data packet to be sent, continuing to send data through the above process; when no subsequent uplink data packet exists and no expected downlink data packet is transmitted, the anchor base station feeds back an acquisition context failure message to the serving base station, and the acquisition context failure message carries an RRC recovery message indicating that the terminal reenters an RRC inactive state, so that the terminal can enter the RRC inactive state according to the configuration.

It should be noted that this method is applicable to uplink packet transmission in a plurality of non-RLC AM modes.

3) And receiving the context acquiring response message fed back by the anchor base station.

That is, in the process, when the auxiliary information indicates that the terminal has a subsequent uplink data packet to be sent and no desired downlink data packet, for the transmission of a plurality of continuous uplink data packets, the anchor base station may determine to perform anchor transfer, feed back an acquisition context response message to the serving base station, and feed back the acquisition context response message to the terminal by the serving base station. In addition, the terminal base station recovers the context of the terminal, so that the terminal enters a connected state, and subsequent uplink data is transmitted in the connected state.

Of course, it should be noted that, in the above-mentioned mode 1-3, when the uplink data packet adopts the RLC AM mode, the context failure information is obtained and also carries the RLC ACK corresponding to the uplink data packet; or, when the uplink data packet adopts the RLC AM mode, the context response message is acquired to carry the RLC ACK corresponding to the uplink data packet.

Specifically, the RLC ACK includes an ACK of the RLC layer and a logical channel identifier corresponding to the uplink data packet; alternatively, the RLC ACK is carried in the MAC PDU.

In addition, it should be noted that the method is applicable to the uplink data packet transmission in multiple RLC AM modes, that is, if it is indicated that the subsequent uplink data packet transmission is performed, the anchor base station may select to perform anchor transfer, and select context transfer to complete continuous multiple uplink data transmission, so that the ACK of each uplink data packet can be timely fed back to the terminal.

In this way, in this embodiment, when receiving an RRC recovery request sent by a terminal in an RRC inactive state, a first context acquisition request message is sent to an anchor base station, and an indication message that indicates whether the terminal reenters the RRC inactive state based on information feedback carried in the first context acquisition request message is received by the anchor base station, so that whether the terminal performs anchor transfer is selected, thereby avoiding a problem that the terminal in the inactive state in the prior art needs anchor transfer only when data is transmitted, avoiding tedious processes of context transfer and path transfer in an anchor transfer process, saving signaling overhead, and reducing service delay.

In addition, as shown in fig. 2, a flowchart of steps of a data transmission method applied to an anchor base station in the embodiment of the present invention is shown, where the method includes the following steps:

step 201: receiving a first context acquiring request message sent by a serving base station.

Specifically, the first context acquiring request message is sent by the serving base station when receiving an RRC recovery request message sent by a terminal in an RRC inactive state, and the first context acquiring request message only carries an uplink data packet or carries the uplink data packet and auxiliary information, where the auxiliary information is used to indicate data to be transmitted;

it should be noted that, for specific contents of the uplink data packet and the first context request obtaining message, reference may be made to relevant contents of the serving base station, and details are not described herein again.

Step 202: and sending an indication message to the service base station based on the information carried in the first context acquiring request message.

In this step, specifically, the indication message is used to indicate whether the terminal enters the RRC inactive state again.

In addition, specifically, the information carried in the first context acquiring request message may be only an uplink data packet carried, or may also be an uplink data packet and auxiliary information carried simultaneously.

Therefore, the anchor base station receives the first context acquiring request message sent by the service base station, and sends an indication message indicating whether the terminal enters the RRC non-activated state again to the service base station based on the information carried in the first context acquiring request message, so that the selection of whether the terminal carries out context transfer, namely anchor transfer is realized, the problem that the anchor transfer is required only when the data is transmitted by the terminal in the non-activated state in the prior art is solved, the complicated processes of context transfer and path transfer in the anchor transfer process are avoided, the signaling overhead is saved, and the service delay is reduced.

In addition, it should be noted that, specifically, the auxiliary information may indicate at least one of the following: the reason value, whether the terminal has a subsequent uplink data packet to be sent, the data volume of the subsequent uplink data packet to be sent, and whether the terminal has an expected downlink data packet. Thereby enabling an indication of the auxiliary information to the data that needs to be transmitted.

Further, a process of the anchor base station sending the indication message to the serving base station based on the information carried in the first acquisition context request message is described herein.

and the anchor base station sends a context acquisition failure message to the service base station, wherein the context acquisition failure message carries an RRC release message indicating the terminal to reenter an RRC non-activated state.

Specifically, before sending the context acquisition failure message to the serving base station, the anchor base station may also send the uplink data packet carried in the first context acquisition request message to the core network node, and determine not to perform anchor transfer.

Second, when the first context acquiring request message carries an uplink data packet and auxiliary information:

when the anchor base station sends the indication message to the serving base station based on the information carried in the first context acquiring request message, the anchor base station may include any one of the following:

first, when the auxiliary information indicates that the terminal has no subsequent uplink data packet to be sent and no desired downlink data packet, it is determined not to perform anchor point transfer and a context acquisition failure message is sent to the serving base station.

And secondly, when the auxiliary information indicates that the terminal has an expected downlink data packet and/or the anchor base station receives the downlink data packet aiming at the terminal, determining to perform anchor transfer and sending a context acquisition response message to the serving base station.

Thirdly, when the auxiliary information indicates that the terminal has a subsequent uplink data packet to be sent and no expected downlink data packet, any one of the following modes can be adopted:

1) after the uplink data packet carried in the first context acquiring request message is sent to the core network node, a context acquiring failure message is sent to the service base station, a second context acquiring request message sent by the service base station is continuously received, and the context acquiring failure message is sent to the service base station after the uplink data packet carried in the second context acquiring request message is sent to the core network node until the subsequent uplink data packet to be sent is sent completely.

Specifically, the second acquisition context request message carries an uplink data packet and auxiliary information; the context acquisition failure message carries an RRC release message indicating that the terminal re-enters an RRC inactive state.

3) And receiving the context acquisition response message fed back by the anchor base station.

It should be noted that, for any sub-embodiment in the first and second cases, reference may be made to the related content of the method embodiment at the serving base station side, and details thereof are not repeated herein.

Furthermore, it should be noted herein that when the uplink data packet adopts the RLC AM mode, the context failure acquisition message also carries an RLC ACK corresponding to the uplink data packet; or, when the uplink data packet adopts the RLC AM mode, the context response message is acquired to carry the RLC ACK corresponding to the uplink data packet.

The present invention will be described in detail with reference to the following examples.

The first embodiment is as follows:

if the terminal in the non-activated state is still in the service range of the anchor base station, when the terminal has the requirement of uplink data transmission, the terminal initiates an RRC recovery Request (RRC Resume Request) process and simultaneously sends an uplink data packet; the anchor base station directly sends the uplink data packet to the core network node; in addition, if there is no (desired) downlink data, the anchor may send the terminal back to the inactive state.

Example two:

the terminal in the inactive state initiates an uplink data transmission process at a serving base station (non-anchor base station), and has no auxiliary information:

referring to fig. 3, this time, the following steps may be included:

step 1, the terminal initiates an RRC recovery Request (RRC Resume Request) to the service base station and simultaneously sends an uplink data packet.

And step 2, the service base station initiates a Request message (Retrieve UE Context Request) for acquiring the Context to the anchor base station of the terminal, wherein the message comprises an uplink data packet of the terminal, and the uplink data packet is sent in a form of MAC PDU.

Step 3, the anchor base station processes and acquires an uplink data packet of the terminal contained in the Context request message, sends the uplink data packet to the core network node, and then feeds back a Context acquisition Failure message (Retrieve UE Context Failure) to the service base station, wherein the Context acquisition Failure message contains RRC Release message; if the uplink data packet of the terminal is in the RLC AM mode, the anchor base station also includes its corresponding RLC ACK in the acquisition context failure message (which may be one or more RLC ACKs depending on the number of DRBs in the RLC AM mode for uplink data transmission).

And step 4, the service base station sends RLC ACK and RRC Release messages to the terminal, wherein the RRC Release messages contain suspend configuration and indicate the terminal to return to an inactive state.

And 5, if the subsequent uplink data transmission exists, repeating the steps 1-4.

Example three: the non-active terminal initiates an uplink data transmission process (with auxiliary information and single uplink transmission) at a serving base station (non-anchor base station):

referring to fig. 4, this time, the following steps may be included:

step 1, the terminal initiates RRC Resume Request to the service base station, and simultaneously sends an uplink data packet and indicates that no subsequent uplink data and expected downlink data exist.

And step 2, the service base station initiates a Retrieve UE Context Request to the anchor base station of the terminal, wherein the Retrieve UE Context Request comprises an uplink data packet of the terminal and indicates that no subsequent uplink data and expected downlink data exist.

Step 3, the anchor base station sends the received uplink data to a core network node, and then feeds back a Retrieve UE Context Failure message to the service base station, wherein the message comprises an RRC Release message; if the uplink data packet of the terminal is RLC AM data, the anchor base station also includes its corresponding RLC ACK in the Retrieve UE Context Failure (possibly one or more RLC ACKs, depending on the number of DRBs of the RLC AM mode of uplink data transmission).

And step 4, the service base station sends RLC ACK and RRC Release information in the Retrieve UE Context Failure information to the terminal, wherein the RRC Release information has suspend configuration and indicates the terminal to return to an inactive state.

Example four: when a serving base station (non-anchor base station) initiates an uplink data transmission process (with auxiliary information, and multiple uplink transmissions, without downlink data), an inactive terminal includes the following modes:

and (i) performing multiple uplink data transmissions, which can also be performed repeatedly in the manner described in the third embodiment.

(II), referring to FIG. 5, the method comprises the following steps:

step 1, the terminal initiates RRC Resume Request to the service base station, and simultaneously sends an uplink data packet and indicates that subsequent uplink data exist and no expected downlink data exist.

Step 2, the service base station initiates a Retrieve UE Context Request to an anchor base station of the terminal, wherein the Retrieve UE Context Request comprises an uplink data packet of the terminal and indicates that subsequent uplink data exist and no expected downlink data exist; and the anchor base station processes the uplink data and sends the uplink data to the core network node.

Step 1x/2x, the terminal sends the subsequent uplink data, which may be sent on a direct DRB, or may be sent together with an RRC signaling; the serving base station sends the received uplink data packet (MAC PDU) to the anchor base station and indicates that a subsequent uplink data packet is to be transmitted. (it should be noted that the signaling used for the subsequent uplink data packet transmission on the interface is not limited, and may be newly defined signaling, and does not exclude the request message for obtaining context in the reuse step 2)

Step 1y/2y, and step 1x/2x, wherein the difference is that the requirement UE Context Request indicates that no subsequent uplink data packet is to be transmitted.

And step 3, the anchor base station sends the received uplink data to the core network node, and then feeds back a Retrieve UE Context Failure message to the service base station, wherein the message comprises an RRC Release message.

And 4, the service base station sends the RRC Release message to the terminal, the message has suspend configuration, and the terminal is indicated to return to the non-activated state.

Third, as shown in fig. 6, the transmission process of the first uplink packet is the same as the transmission process of the previous embodiment. In addition, the anchor base station obtains the terminal and subsequent uplink data transmission according to the auxiliary information in the Retrieve UE Context Request, and even obtains the subsequent data volume to be transmitted. The anchor base station may decide to perform Context transfer, and thus feed back a terminal Context Response message (Retrieve UE Context Response) to the serving base station. If the uplink data packet of the terminal is RLC AM data, the anchor base station also includes its corresponding RLC ACK in the Retrieve UE Context Response (the message may include 1 or more RLC ACKs, depending on the number of DRBs in the RLC AM mode for uplink data transmission).

Then, after acquiring the context of the terminal, the serving base station recovers the RRC on the air interface (sends an RRC response message and receives an RRC response Complete message), and performs Path transfer (exchanges a Path Switch Request (Path Switch Request) and a Path Switch Request acknowledgement (Path Switch Request ACK) message with the core network node). And the subsequent uplink and downlink data transmission is completed between the service base station and the core network node.

Example five: the non-active terminal initiates an uplink data transmission process (with auxiliary information and downlink) at a serving base station (non-anchor base station):

referring to fig. 7, if the terminal has expected downlink data or the anchor base station has received the downlink data from the core network node, the anchor base station may recover the air interface connection of the terminal, so that the terminal enters the RRC connection state, no matter whether there are multiple uplink data to be sent in the process.

It should be noted that the process is the same as the process in (i) in the fourth embodiment, and is not repeated herein.

Thus, the embodiment realizes that the anchor base station determines whether to perform anchor transfer according to the information carried in the context acquiring request message, namely, performs context transfer, thereby avoiding the complex context transfer and path transfer processes in the prior art, saving signaling overhead and reducing service delay when only a small amount of uplink data transmission is required.

In addition, as shown in fig. 8, a block diagram of a data transmission apparatus applied to a serving base station in an embodiment of the present invention is shown, where the apparatus includes:

a sending module 801, configured to send a first context acquisition request message to an anchor base station when receiving an RRC recovery request message sent by a terminal in an RRC inactive state of radio resource control; the first context acquiring request message only carries an uplink data packet, or carries the uplink data packet and auxiliary information, and the auxiliary information is used for indicating data to be transmitted;

a receiving module 802, configured to receive an indication message fed back by the anchor base station based on information carried in the first context request obtaining message, where the indication message is used to indicate whether the terminal reenters an RRC inactive state.

Optionally, the assistance information indicates at least one of: the reason value, whether the terminal has a subsequent uplink data packet to be sent, the data volume of the subsequent uplink data packet to be sent, and whether the terminal has an expected downlink data packet.

Optionally, when the first context acquiring request message only carries an uplink data packet, the receiving module is configured to receive a context acquiring failure message fed back by the anchor base station, where the context acquiring failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state.

It should be noted that, the apparatus can implement all the method steps of the method embodiment of the serving base station, and the same method steps and beneficial effects are not described again here.

In addition, as shown in fig. 9, a block diagram of a data transmission apparatus applied to an anchor base station in the embodiment of the present invention is shown, where the apparatus includes:

a receiving module 901, configured to receive a first context obtaining request message sent by a serving base station, where the first context obtaining request message is sent by the serving base station when receiving an RRC recovery request message sent by a terminal in an RRC inactive state of radio resource control, and the first context obtaining request message only carries an uplink data packet or carries an uplink data packet and auxiliary information, where the auxiliary information is used to indicate data to be transmitted;

a sending module 902, configured to send an indication message to the serving base station based on information carried in the first context request obtaining message, where the indication message is used to indicate whether the terminal reenters an RRC inactive state.

Optionally, when the first context acquiring request message only carries an uplink data packet, the sending module is configured to send a context acquiring failure message to the serving base station, where the context acquiring failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state.

It should be noted that, the apparatus can implement all the method steps of the anchor base station side method embodiment, and the same method steps and beneficial effects are not described again here.

In addition, as shown in fig. 10, an entity structure diagram of a serving base station provided in the embodiment of the present invention is shown, where the serving base station may include: a processor (processor)1010, a communication Interface (Communications Interface)1020, a memory (memory)1030, and a communication bus 1040, wherein the processor 1010, the communication Interface 1020, and the memory 1030 communicate with each other via the communication bus 1040. Processor 1010 may invoke a computer program stored on memory 1030 and executable on processor 1010 to perform the following steps:

when receiving an RRC recovery request message sent by a terminal in a Radio Resource Control (RRC) non-activated state, sending a first context acquisition request message to an anchor point base station; the first context acquiring request message only carries an uplink data packet, or carries the uplink data packet and auxiliary information, and the auxiliary information is used for indicating data to be transmitted; and receiving an indication message fed back by the anchor base station based on the information carried in the first context acquiring request message, wherein the indication message is used for indicating whether the terminal reenters an RRC (radio resource control) inactive state.

Optionally, when the first context acquiring request message only carries an uplink data packet, the receiving, by the anchor base station, an indication message fed back based on information carried in the first context acquiring request message includes: and receiving a context acquisition failure message fed back by the anchor base station, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state.

Optionally, when the first context acquiring request message carries an uplink data packet and auxiliary information, the receiving, by the anchor base station, an indication message fed back based on the information carried in the first context acquiring request message includes: when the auxiliary information indicates that the terminal has no subsequent uplink data packet to be sent and no expected downlink data packet, receiving a context acquisition failure message fed back by the anchor base station when the anchor base station does not receive the downlink data packet for the terminal, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state; or, when the auxiliary information indicates that the terminal has an expected downlink data packet and/or the anchor base station receives a downlink data packet for the terminal, receiving an acquisition context response message fed back by the anchor base station, where the acquisition context response message indicates that the terminal enters an RRC connected state.

Optionally, when the first context acquiring request message carries an uplink data packet and auxiliary information, the receiving, by the anchor base station, an indication message fed back based on the information carried in the first context acquiring request message includes: when the auxiliary information indicates that the terminal has subsequent uplink data packets to be sent and does not have expected downlink data packets,

receiving a context acquiring failure message fed back by the anchor base station after the uplink data packet carried in the first context acquiring request message is sent to a core network node, continuing to send a second context acquiring request message to the anchor base station, and receiving a context acquiring failure message fed back by the anchor base station after the uplink data packet carried in the second context acquiring request message is sent to the core network node until the subsequent uplink data packet to be sent is sent; the second context acquiring request message carries an uplink data packet and auxiliary information, and the context acquiring failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state; or, the serving base station continues to send at least one third context acquisition request message to the anchor base station, and receives the context acquisition failure message fed back by the anchor base station when the auxiliary information in the third context acquisition request message indicates that the terminal has no subsequent uplink data packet to be sent and no desired downlink data packet, where the third context acquisition request message carries an uplink data packet and auxiliary information; or receiving a context acquiring response message fed back by the anchor base station, wherein the context acquiring response message indicates that the terminal enters an RRC (radio resource control) connection state.

Optionally, when the uplink data packet is in an RLC acknowledged AM mode, the context acquisition failure message also carries an RLC acknowledgement character ACK corresponding to the uplink data packet; alternatively, the first and second electrodes may be,

and when the uplink data packet adopts an RLC AM mode, the context acquiring response message carries an RLC ACK corresponding to the uplink data packet.

Optionally, the RLC ACK includes an ACK of an RLC layer and a logical channel identifier corresponding to the uplink data packet; alternatively, the RLC ACK is carried in a medium access control protocol data unit, MAC PDU.

It should be noted that, the serving base station may implement all the method steps of the method embodiment of the serving base station, and the same method steps and beneficial effects are not described herein again.

Furthermore, the logic instructions in the memory 1030 can be implemented in software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

In addition, as shown in fig. 11, an entity structure diagram of an anchor point base station provided in the embodiment of the present invention is shown, where the anchor point base station may include: a processor (processor)1110, a communication Interface (Communications Interface)1120, a memory (memory)1130, and a communication bus 1140, wherein the processor 1110, the communication Interface 1120, and the memory 1130 communicate with each other via the communication bus 1140. The processor 1110 may invoke a computer program stored on the memory 1130 and executable on the processor 1110 to perform the steps of:

receiving a first context acquiring request message sent by a serving base station, wherein the first context acquiring request message is sent when the serving base station receives an RRC recovery request message sent by a terminal in an RRC (radio resource control) inactive state, and the first context acquiring request message only carries an uplink data packet or carries the uplink data packet and auxiliary information, and the auxiliary information is used for indicating data to be transmitted; and sending an indication message to the serving base station based on the information carried in the first context acquiring request message, wherein the indication message is used for indicating whether the terminal reenters an RRC (radio resource control) inactive state.

Optionally, when the first context acquiring request message only carries an uplink data packet, the sending an indication message to the serving base station based on information carried in the first context acquiring request message includes: and sending a context acquisition failure message to the serving base station, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state.

Optionally, before sending the context acquisition failure message to the serving base station, the method further includes: and sending the uplink data packet carried in the first context acquiring request message to a core network node, and determining not to perform anchor point transfer.

Optionally, when the first context acquiring request message carries an uplink data packet and auxiliary information, the sending an indication message to the serving base station based on the information carried in the first context acquiring request message includes: when the auxiliary information indicates that the terminal has no subsequent uplink data packet to be sent and no expected downlink data packet, determining not to perform anchor transfer and sending a context acquisition failure message to the serving base station, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state; or, when the auxiliary information indicates that the terminal has an expected downlink data packet and/or the anchor base station receives the downlink data packet for the terminal, determining to perform anchor transfer and sending an acquisition context response message to the serving base station, where the acquisition context response message indicates that the terminal enters an RRC connected state.

Optionally, when the first context acquiring request message carries an uplink data packet and auxiliary information, the sending an indication message to the serving base station based on the information carried in the first context acquiring request message includes: when the auxiliary information indicates that the terminal has subsequent uplink data packets to be sent and does not have expected downlink data packets,

after sending the uplink data packet carried in the first context acquiring request message to a core network node, sending a context acquiring failure message to the serving base station, continuing to receive a second context acquiring request message sent by the serving base station, and sending the context acquiring failure message to the serving base station after sending the uplink data packet carried in the second context acquiring request message to the core network node until the subsequent uplink data packet to be sent is sent; the second context acquiring request message carries an uplink data packet and auxiliary information, and the context acquiring failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state; or, continuously receiving at least one third context acquisition request message sent by the serving base station, and sending the context acquisition failure message to the anchor base station when auxiliary information in the third context acquisition request message indicates that the terminal has no subsequent uplink data packet to be sent and no desired downlink data packet, where the third context acquisition request message carries an uplink data packet and auxiliary information; or, determining to perform anchor transfer and sending a context acquisition response message to the serving base station, wherein the context acquisition response message indicates that the terminal enters an RRC connected state.

Optionally, when the uplink data packet is in an RLC acknowledged AM mode, the context acquisition failure message also carries an RLC acknowledgement character ACK corresponding to the uplink data packet; or, when the uplink data packet is in the RLC AM mode, the context acquiring response message carries an RLC ACK corresponding to the uplink data packet.

It should be noted that, the anchor base station can implement all the method steps of the anchor base station side method embodiment, and the same method steps and beneficial effects are not described herein again.

Embodiments of the present invention further provide a non-transitory computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the methods provided in the foregoing embodiments, and details of the same method steps and beneficial effects are not repeated herein.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware. With this understanding in mind, the above-described technical solutions may be embodied in the form of a software product, which can be stored in a computer-readable storage medium such as ROM/RAM, magnetic disk, optical disk, etc., and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in the embodiments or some parts of the embodiments.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A data transmission method applied to a serving base station is characterized by comprising the following steps:

2. The data transmission method of claim 1, wherein the assistance information indicates at least one of: the reason value, whether the terminal has a subsequent uplink data packet to be sent, the data volume of the subsequent uplink data packet to be sent, and whether the terminal has an expected downlink data packet.

3. The data transmission method according to claim 1, wherein when the first context request acquisition message only carries an uplink data packet, the receiving of the indication message fed back by the anchor base station based on the information carried in the first context request acquisition message includes:

and receiving a context acquisition failure message fed back by the anchor base station, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state.

4. The data transmission method according to claim 1, wherein when the first context request acquisition message carries an uplink data packet and auxiliary information, the receiving the indication message fed back by the anchor base station based on the information carried in the first context request acquisition message includes:

when the auxiliary information indicates that the terminal has no subsequent uplink data packet to be sent and no expected downlink data packet, receiving a context acquisition failure message fed back by the anchor base station when the anchor base station does not receive the downlink data packet for the terminal, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state; alternatively, the first and second electrodes may be,

and when the auxiliary information indicates that the terminal has an expected downlink data packet and/or the anchor base station receives the downlink data packet for the terminal, receiving an acquisition context response message fed back by the anchor base station, wherein the acquisition context response message indicates that the terminal enters an RRC (radio resource control) connection state.

5. The data transmission method according to claim 1, wherein when the first context request acquisition message carries an uplink data packet and auxiliary information, the receiving the indication message fed back by the anchor base station based on the information carried in the first context request acquisition message includes:

when the auxiliary information indicates that the terminal has subsequent uplink data packets to be sent and does not have expected downlink data packets,

receiving a context acquiring failure message fed back by the anchor base station after the uplink data packet carried in the first context acquiring request message is sent to a core network node, continuing to send a second context acquiring request message to the anchor base station, and receiving a context acquiring failure message fed back by the anchor base station after the uplink data packet carried in the second context acquiring request message is sent to the core network node until the subsequent uplink data packet to be sent is sent; the second context acquiring request message carries an uplink data packet and auxiliary information, and the context acquiring failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state;

alternatively, the first and second electrodes may be,

the serving base station continuously sends at least one third context acquisition request message to the anchor base station, and receives the context acquisition failure message fed back by the anchor base station when auxiliary information in the third context acquisition request message indicates that the terminal has no subsequent uplink data packet to be sent and no desired downlink data packet, wherein the third context acquisition request message carries the uplink data packet and the auxiliary information;

alternatively, the first and second electrodes may be,

and receiving a context acquiring response message fed back by the anchor base station, wherein the context acquiring response message indicates the terminal to enter an RRC (radio resource control) connection state.

6. The data transmission method according to any one of claims 3 to 5,

when the uplink data packet adopts an RLC (radio link control) acknowledged AM (amplitude modulation) mode, the context acquisition failure message also carries an RLC acknowledged character ACK corresponding to the uplink data packet; alternatively, the first and second electrodes may be,

7. The data transmission method according to claim 6, wherein the RLC ACK includes an RLC layer ACK and a logical channel identifier corresponding to the uplink data packet; alternatively, the RLC ACK is carried in a medium access control protocol data unit, MAC PDU.

8. A data transmission method is applied to an anchor point base station, and is characterized by comprising the following steps:

9. The data transmission method of claim 8, wherein the side information indicates at least one of: the reason value, whether the terminal has a subsequent uplink data packet to be sent, the data volume of the subsequent uplink data packet to be sent, and whether the terminal has an expected downlink data packet.

10. The data transmission method according to claim 8, wherein when the first get context request message only carries an uplink data packet, the sending an indication message to the serving base station based on information carried in the first get context request message includes:

and sending a context acquisition failure message to the serving base station, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state.

11. The data transmission method according to claim 10, wherein before sending the acquisition context failure message to the serving base station, the method further comprises:

and sending the uplink data packet carried in the first context acquiring request message to a core network node, and determining not to perform anchor point transfer.

12. The data transmission method according to claim 8, wherein when the first get context request message carries an uplink data packet and auxiliary information, the sending an indication message to the serving base station based on the information carried in the first get context request message includes:

when the auxiliary information indicates that the terminal has no subsequent uplink data packet to be sent and no expected downlink data packet, determining not to perform anchor transfer and sending a context acquisition failure message to the serving base station, wherein the context acquisition failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state; alternatively, the first and second electrodes may be,

when the auxiliary information indicates that the terminal has an expected downlink data packet and/or the anchor base station receives the downlink data packet for the terminal, determining to perform anchor transfer and sending a context acquisition response message to the serving base station, wherein the context acquisition response message indicates that the terminal enters an RRC (radio resource control) connected state.

13. The data transmission method according to claim 8, wherein when the first get context request message carries an uplink data packet and auxiliary information, the sending an indication message to the serving base station based on the information carried in the first get context request message includes:

after sending the uplink data packet carried in the first context acquiring request message to a core network node, sending a context acquiring failure message to the serving base station, continuing to receive a second context acquiring request message sent by the serving base station, and sending the context acquiring failure message to the serving base station after sending the uplink data packet carried in the second context acquiring request message to the core network node until the subsequent uplink data packet to be sent is sent; the second context acquiring request message carries an uplink data packet and auxiliary information, and the context acquiring failure message carries an RRC release message indicating that the terminal reenters an RRC inactive state;

alternatively, the first and second electrodes may be,

continuously receiving at least one third context acquiring request message sent by the serving base station, and sending a context acquiring failure message to the anchor base station when auxiliary information in the third context acquiring request message indicates that a terminal has no subsequent uplink data packet to be sent and no desired downlink data packet, wherein the third context acquiring request message carries the uplink data packet and the auxiliary information;

alternatively, the first and second electrodes may be,

determining to perform anchor transfer and sending a context acquisition response message to the serving base station, wherein the context acquisition response message indicates that the terminal enters an RRC connected state.

14. The data transmission method according to any one of claims 10 to 13,

15. The data transmission method according to claim 14, wherein the RLC ACK includes an RLC layer ACK and a logical channel identifier corresponding to the uplink data packet; alternatively, the RLC ACK is carried in a medium access control protocol data unit, MAC PDU.

16. A data transmission apparatus for a serving base station, comprising:

17. A data transmission apparatus for an anchor base station, comprising:

18. A serving base station comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor when executing the computer program performs the steps of:

19. The serving base station of claim 18, wherein the assistance information indicates at least one of: the reason value, whether the terminal has a subsequent uplink data packet to be sent, the data volume of the subsequent uplink data packet to be sent, and whether the terminal has an expected downlink data packet.

20. The serving base station of claim 18, wherein when the first get context request message only carries an uplink data packet, the receiving the indication message fed back by the anchor base station based on the information carried in the first get context request message includes:

21. The serving base station of claim 18, wherein when the first get context request message carries an uplink data packet and auxiliary information, the receiving the indication message fed back by the anchor base station based on the information carried in the first get context request message includes:

22. The serving base station of claim 18, wherein when the first get context request message carries an uplink data packet and auxiliary information, the receiving the indication message fed back by the anchor base station based on the information carried in the first get context request message includes:

alternatively, the first and second electrodes may be,

23. An anchor base station comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor when executing the computer program performs the steps of:

24. The anchor base station of claim 23, wherein the assistance information indicates at least one of: the reason value, whether the terminal has a subsequent uplink data packet to be sent, the data volume of the subsequent uplink data packet to be sent, and whether the terminal has an expected downlink data packet.

25. The anchor base station of claim 23, wherein when the first context request message only carries an uplink data packet, the sending an indication message to the serving base station based on information carried in the first context request message comprises:

26. The anchor base station of claim 23, wherein when the first context request message carries an uplink data packet and auxiliary information, the sending an indication message to the serving base station based on the information carried in the first context request message comprises:

27. The anchor base station of claim 23, wherein when the first context request message carries an uplink data packet and auxiliary information, the sending an indication message to the serving base station based on the information carried in the first context request message comprises:

alternatively, the first and second electrodes may be,

28. A non-transitory computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the data transmission method according to any one of claims 1 to 7 or carries out the steps of the data transmission method according to any one of claims 8 to 15.