CN110944368A

CN110944368A - Method and equipment for transmitting data in switching process

Info

Publication number: CN110944368A
Application number: CN201811119684.1A
Authority: CN
Inventors: 刘佳敏; 张大钧
Original assignee: China Academy of Telecommunications Technology CATT
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2018-09-25
Filing date: 2018-09-25
Publication date: 2020-03-31

Abstract

The invention discloses a method and equipment for transmitting data in a switching process, which are used for solving the problem that a terminal in the prior art has larger data transmission delay during switching. In the embodiment of the invention, after determining that data connection needs to be maintained with source and target network side equipment, a terminal maintains data connection with the source network side equipment through a first entity which is correspondingly loaded and bound with a PDCP entity and performs data transmission; and meanwhile, the other set of second entity bound with the PDCP entity corresponding to the bearer keeps data connection with the target network side equipment and carries out data transmission. Therefore, when the terminal determines that data connection with the source network side equipment and the target network side equipment is required in the switching process, the data connection with the source network side equipment and the target network side equipment can be simultaneously maintained through two sets of MAC entities or RLC entities, so that data transmission between the terminal and the network side equipment is uninterrupted, and the data interruption time delay in the terminal switching process is shortened.

Description

Method and equipment for transmitting data in switching process

Technical Field

The present invention relates to the field of wireless communications technologies, and in particular, to a method and a device for transmitting data during handover.

Background

The mobility event refers to an event that the network triggers the terminal to perform network handover after the terminal moves to a position where signal coverage of two network entities overlap. In the switching process, data transmission at the original side needs to be interrupted first, and service transmission is continued after the original side is accessed to the target network side equipment, so that data transmission is not performed in the whole switching process, and further, larger data interruption is caused.

With the continuous evolution of networks, the mobility event between network side devices in the conventional network architecture cannot meet the higher requirement for mobility performance. For example, keeping data interruption during handover to a minimum (even 0ms) has become a fundamental requirement for the development of next generation networks.

In order to reduce the time delay of the handover process, some improved methods have been studied, such as RACH-Less (random access channel-Less, which omits the random access channel process) handover, MBB (Make before break), and the like, but the RACH-Less only saves the time delay of the random access to the target cell during the handover process. In the above method, the terminal has very strict preconditions during network handover, that is, the source cell and the target cell are strictly synchronized and the TA (Time Alignment) timing advance is 0 or the source and the target are completely the same.

In summary, in the prior art, a terminal has a large data transmission delay when performing handover.

Disclosure of Invention

The invention provides a method and equipment for transmitting data in a switching process, which are used for solving the problem that a terminal in the prior art has larger data transmission delay during switching.

In a first aspect, an embodiment of the present invention provides a method for transmitting data in a handover process, where the method includes:

after a terminal needs to maintain Data connection with a source network side device and a target network side device in a switching process, the terminal maintains Data connection with the source network side device through a first Data entity corresponding to a bearer and maintains Data connection with the target network side device through a second Data entity corresponding to the bearer, wherein the Data entity is an MAC (Media Access Control) entity or an RLC (Radio Link Control, Radio Link layer Control Protocol) entity, and the first Data entity and the second Data entity are bound to the same PDCP (Packet Data Convergence Protocol) entity; and then the terminal transmits data with the source network side equipment through the first data entity and transmits data with the target network side equipment through the second data entity in the switching process.

In the embodiment of the invention, after determining that the terminal needs to keep data connection with the source network side equipment and the target network side equipment in the switching process, the terminal keeps data connection with the source network side equipment through a corresponding MAC entity or RLC entity bound with the PDCP entity by bearing, and transmits data with the source network side equipment through the MAC entity or RLC entity in the switching process; meanwhile, the other set of MAC entity or RLC entity bound with the PDCP entity and corresponding to the bearer maintains data connection with the target network side equipment, and transmits data with the target network side equipment through the MAC entity or RLC entity in the switching process. Therefore, when the terminal determines that data connection with the source network side device and the target network side device is required in the switching process, the data connection with the source network side device and the target network side device can be simultaneously maintained through two sets of MAC entities or RLC entities, and data transmission is carried out, so that data transmission between the terminal and the network side device is uninterrupted, and the data transmission delay time in the terminal switching process is greatly shortened.

In a possible implementation manner, after receiving the indication information including the special handover, the terminal determines that data connection needs to be maintained with the source network-side device and the target network-side device in the handover process.

In the method, the terminal only needs to judge whether the data connection with the source network side equipment and the target network side equipment is needed in the current switching process according to whether the received switching instruction contains the indication information of the special switching or not, and other condition restrictions are not needed, so that the method can be more widely applied to various network switching environments.

In a possible implementation manner, after the terminal needs to maintain data connection with the source network side device and the target network side device in the handover process, the terminal maintains data connection with the source network side device through a first data entity corresponding to the established bearer; and newly establishing a second data entity, and maintaining data connection with the target network side equipment through the second data entity corresponding to the bearer.

In the method, when the terminal determines that data connection needs to be maintained with the source network side device and the target network side device at the same time, the terminal maintains the data connection with the source network side device through the MAC entity or the RLC entity which is bound with the PDCP entity and corresponds to the established bearer; and simultaneously, a set of MAC entity or RLC entity bound with the PDCP entity is newly established, and the data connection is kept between the MAC entity or the RLC entity corresponding to the load bearing and the target network side equipment. Thus, the embodiment of the invention can utilize the existing established bearer to maintain data connection with the source network side equipment, and only adds a set of MAC entity or RLC entity corresponding to the target network side equipment on the terminal side, thereby greatly utilizing the existing layer 2 structure, not only reducing the time delay of data transmission in the switching process, but also making the scheme have lower difficulty in implementation.

In a possible implementation manner, the terminal transmits data with a source network side device through a first data entity and transmits data with a target network side device through a second data entity in a handover process, including:

the terminal reports a first BSR (Buffer Status Report) to the source network side equipment through a first data entity and reports a second BSR to the target network side equipment through a second data entity in the switching process;

the first BSR includes a first SRB (signaling Radio Bearer) Data amount and/or a first DRB (Data Radio Bearer) number, where the first SRB Data amount is a Data amount of a signaling that the terminal needs to send to a source network side device, and the first DRB Data amount is a total amount of all user Data that the terminal needs to send or a Data amount of a part of user Data that needs to send;

the second BSR includes a second SRB data volume and/or a second DRB data volume, where the second SRB data volume is a data volume of a signaling that the terminal needs to send to a target network side device, and the second DRB data volume is a total amount of all user data that the terminal needs to send or a data volume of a part of user data that needs to be sent.

In the method, the terminal reports the first BSR corresponding to the source network side device to the first SRB data volume and/or the first DRB data volume of the source network side device through the existing MAC entity or RLC entity bound to the PDCP entity, where the first SRB data volume is a data volume of a signaling that the terminal needs to send to the source network side device, and the first DRB data volume is a total amount of all user data that the terminal needs to send or a data volume of a part of user data that needs to be sent, so that the source network side device can configure corresponding resources according to the reported first BSR for data transmission between the terminal and the source network device.

Meanwhile, the terminal reports a second BSR corresponding to the target network side device through a newly established MAC entity or RLC entity bound to the PDCP entity, where the second BSR includes a second SRB data volume and/or a second DRB data volume, the second SRB data volume is a data volume of a signaling that the terminal needs to send to the target network side device, and the second DRB data volume is a total amount of all user data that the terminal needs to send or a data volume of a part of user data that needs to be sent, so that the source network side device can configure corresponding resources according to the reported second BSR for data transmission between the terminal and the target network device.

In a possible implementation manner, the terminal transmits data with a source network side device through a first data entity and transmits data with a target network side device through a second data entity in a handover process, further including:

and the terminal processes the data transmitted between the terminal and the source network side equipment by utilizing the security and header compression context corresponding to the source network side equipment through the PDCP layer, and processes the data transmitted between the terminal and the target network side equipment by utilizing the security and header compression context corresponding to the target network side equipment through the PDCP layer.

In the method, the terminal may process the data transmitted between the terminal and the source network side device by using the security and header compression context corresponding to the source network side device through the PDCP layer, and at the same time, process the data transmitted between the terminal and the target network side device by using the security and header compression context corresponding to the target network side device through the PDCP layer. That is, the terminal side maintains two sets of security and header compression contexts corresponding to the source network side device and the target network side device at the same time, so that the terminal can simultaneously maintain data transmission connection with the source network side device and the target network side device.

In a possible implementation manner, the processing, by the terminal, data transmitted between the terminal and the source network-side device by using a security header compression context corresponding to the source network-side device through the PDCP layer, and processing data transmitted between the terminal and the target network-side device by using a security header compression context corresponding to the target network-side device through the PDCP layer includes:

and the terminal processes the data transmitted between the terminal and the source network side equipment by utilizing the security and header compression context corresponding to the source network side equipment through the PDCP layer before the set time, and processes the data transmitted between the terminal and the target network side equipment by utilizing the security and header compression context corresponding to the target network side equipment through the PDCP layer after the set time.

Compared with the method for maintaining the security and header compression context corresponding to two sets of network side equipment, the method has the advantages that when only one set of security and header compression context corresponding to one set of network side equipment is maintained, the load of the terminal is small, and the implementation difficulty is relatively low.

In a possible embodiment, the set time is one of the following times:

the time when the random access of the target network side equipment is successful;

the time when the data entity of the terminal receives the first downlink data packet;

the time when the data entity of the terminal receives the first special data scheduling;

and the time when the terminal and the target network side equipment are successfully connected is shown.

In the method, after the MAC layer of the terminal succeeds in random access to the target network side equipment, the PDCP layer is informed to start resetting and use related parameters of safety and header compression of the target network side equipment; or when the RLC entity or the MAC entity of the target network side equipment receives a first downlink data packet from the terminal, informing the PDCP layer of the terminal side to start resetting and using related parameters of safety and header compression of the target network side equipment; or when the RLC entity or MAC entity of the target network side device receives the first dedicated data scheduling from the target network side device of the terminal, the scheduling resource may be uplink or downlink, notifies the PDCP layer of the terminal side, and starts to reset and use the security and header compression related parameters of the target network side device; or other time point which can indicate that the connection between the terminal and the target network side device is successful, the PDCP layer of the terminal side is informed to start resetting and using the security and header compression related parameters of the target network side device.

In one possible embodiment, the method further comprises:

and the terminal determines that the data needing to be processed belongs to the source network side equipment or the target network side equipment according to the bottom layer notification received by the PDCP layer.

In the method, the bottom layer of the terminal determines that the data to be processed belongs to the source network side equipment or the target network side equipment, transmits the determined result to the PDCP layer, finally determines that the data to be processed belongs to the source network side equipment or the target network side equipment, and can process the data to be processed by adopting the corresponding security and header compression context according to the determined result.

In a possible implementation manner, the terminal determines, through the PDCP layer, that the data to be processed belongs to the source network side device or the target network side device according to indication information in the data to be processed.

In the method, the network side equipment inserts indication information indicating the source of the data to be transmitted in the switching process, after the terminal receives the information and before the terminal processes the information, the PDCP of the terminal determines the attribution of the data according to the indication information in the transmitted data, and then processes the data according to the determined security and header compression context corresponding to the network side equipment.

In a second aspect, an embodiment of the present invention provides a method for transmitting data in a handover process, where the method includes:

a source network side device keeps data connection with a terminal through a first data entity corresponding to a bearer in the switching process of the terminal, wherein the terminal keeps data connection with a target network side device at the same time; wherein the data entity is a MAC entity or an RLC entity, and the first data entity is bound with the PDCP entity;

and the source network side equipment transmits data with the terminal through the first data entity.

In the method, while the terminal and the target network side device keep data connection, the source network side device keeps data connection with the terminal through the MAC entity or the RLC entity which bears the corresponding PDCP entity and is bound with the terminal in the switching process of the terminal, and realizes data transmission with the terminal through the MAC entity or the RLC entity. And then the terminal can simultaneously keep data connection with the source network side device and the target network side device in the switching process.

In a possible implementation manner, the source network side device disconnects the data connection maintained with the terminal through the first data entity corresponding to the bearer after determining that the terminal has been handed over to the target network side device.

In a possible implementation manner, the source network side device determines that the terminal has been handed over to the target network side device by using part or all of the following manners:

the data transmission requirement between the terminal and the terminal cannot be met;

the data is not received after the uplink authorization is sent to the terminal;

feedback is not received after downlink data is sent to the terminal;

and after uplink transmission is configured for the terminal, the uplink signal is not received.

According to the method, when it is determined that data transmission cannot be performed between the source network side equipment and the terminal, the source network side equipment disconnects the data connection kept between the first data entity corresponding to the bearer and the terminal, and network switching is completed.

In a possible implementation manner, when a set duration after the source network-side device sends the handover command arrives, the source network-side device forwards data and/or transmits an SN (Sequence Number) state to the target network-side device;

and after receiving the trigger of the target network side equipment, the source network side equipment forwards data and/or transmits an SN state to the target network side equipment.

According to the method, when the set time length after the source network side equipment sends the switching command is reached, or after the trigger of the target network side equipment is received, the source network side equipment forwards data and/or transmits the SN state to the target network side equipment, so that the integrity of the data received by the terminal can be ensured.

In a third aspect, an embodiment of the present invention provides a method for transmitting data in a handover process, where the method includes:

the target network side equipment keeps data connection with the terminal through a second data entity corresponding to the load in the switching process of the terminal, wherein the terminal keeps data connection with the source network side equipment at the same time; wherein the data entity is a MAC entity or an RLC entity, and the second data entity is bound with the PDCP entity;

and the target network side equipment transmits data with the terminal through a second data entity.

According to the method, while the terminal keeps data connection with the source network side device, the target network side device keeps data connection with the terminal through the MAC entity or the RLC entity which bears the corresponding PDCP entity and is bound with the PDCP entity in the switching process of the terminal, and data transmission with the terminal is achieved through the MAC entity or the RLC entity, so that the terminal can simultaneously keep data connection with the source network side device and the target network side device in the switching process.

In a possible implementation manner, the target network side device triggers the source network side device to forward data and/or transfer an SN status after the terminal starts to access the target network side device.

In the method, the target network side device triggers the source network side device to forward data and/or transmit an SN (service number) state after the terminal starts to access the target network side device, so that the data received by the terminal is kept complete.

In a possible implementation manner, the target network side device notifies the source network side device to release the context of the terminal after the terminal accesses the target network side device or the terminal completes handover.

According to the method, the target network side equipment informs the source network side equipment to release the context of the terminal after the terminal is accessed to the target network side equipment or the terminal is switched to be finished, so that the resources of the terminal are released, and further data transmission can be better carried out with the target network side equipment.

In a fourth aspect, an embodiment of the present invention provides a terminal for transmitting data in a handover process, where the terminal includes: a processor, a memory, and a transceiver;

wherein the processor is configured to read a program in the memory and execute:

after data connection with source network side equipment and target network side equipment is required to be maintained in a switching process, the data connection is maintained with the source network side equipment through a first data entity corresponding to a load, and the data connection is maintained with the target network side equipment through a second data entity corresponding to the load, wherein the data entity is an MAC (media access control) entity or an RLC (radio link control) entity, and the first data entity and the second data entity are bound with the same PDCP (packet data convergence protocol) entity; and transmitting data with the source network side equipment through the first data entity and transmitting data with the target network side equipment through the second data entity in the switching process.

In a fifth aspect, an embodiment of the present invention provides a source network device for transmitting data in a handover process, where the source network device includes: a processor, a memory, and a transceiver;

in the switching process of the terminal, the terminal keeps data connection with the terminal through a first data entity corresponding to the load, wherein the terminal keeps data connection with target network side equipment at the same time; wherein the data entity is a MAC entity or an RLC entity, and the first data entity is bound with the PDCP entity; and transmitting data with the terminal through the first data entity.

In a sixth aspect, an embodiment of the present invention provides a target network side device for transmitting data in a handover process, where the target network side device includes: a processor, a memory, and a transceiver;

in the switching process of the terminal, the terminal keeps data connection with the terminal through a second data entity corresponding to the load, wherein the terminal keeps data connection with the source network side equipment at the same time; wherein the data entity is a MAC entity or an RLC entity, and the second data entity is bound with the PDCP entity; and transmitting data with the terminal through the second data entity.

In a seventh aspect, an embodiment of the present invention provides a terminal for transmitting data in a handover process, where the terminal includes:

the connection module is used for keeping data connection with source network side equipment and target network side equipment through a first data entity corresponding to a bearer and keeping data connection with the source network side equipment through a second data entity corresponding to the bearer in the switching process, wherein the data entity is an MAC (media access control) entity or an RLC (radio link control) entity, and the first data entity and the second data entity are bound with the same PDCP (packet data convergence protocol) entity;

and the data transmission module is used for transmitting data with the source network side equipment through the first data entity and transmitting data with the target network side equipment through the second data entity in the switching process.

In an eighth aspect, an embodiment of the present invention provides a source network device for transmitting data in a handover process, where the source network device includes:

the terminal comprises a connection module, a switching module and a switching module, wherein the connection module is used for keeping data connection with the terminal through a first data entity corresponding to a bearer in the switching process of the terminal, and the terminal simultaneously keeps data connection with target network side equipment; wherein the data entity is a MAC entity or an RLC entity, and the first data entity is bound with the PDCP entity;

and the data transmission module is used for transmitting data with the terminal through the first data entity.

In a ninth aspect, an embodiment of the present invention provides a target network side device for transmitting data in a handover process, where the target network side device includes:

the connection module is used for keeping data connection with the terminal through a second data entity corresponding to the bearer in the switching process of the terminal, wherein the terminal simultaneously keeps data connection with the source network side equipment; wherein the data entity is a MAC entity or an RLC entity, and the second data entity is bound with the PDCP entity;

and the data transmission module is used for transmitting data with the terminal through the second data entity.

In addition, for technical effects brought by any one implementation manner of the fourth aspect to the ninth aspect, reference may be made to technical effects brought by different implementation manners of the first aspect and the third aspect, and details are not described here again.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic diagram of a network-side device-side protocol stack structure according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a terminal-side protocol stack structure according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a system for transmitting data during handover according to an embodiment of the present invention;

fig. 4 is a timing diagram illustrating a method for transmitting data during handover according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a terminal for transmitting data in a first handover process according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a source network side device for transmitting data in a first handover process according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a target network side device for transmitting data in a first handover process according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a terminal for transmitting data in a second handover process according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a source network side device for transmitting data in a second handover process according to an embodiment of the present invention;

fig. 10 is a schematic structural diagram of a target network side device for transmitting data in a second handover process according to an embodiment of the present invention;

fig. 11 is a flowchart illustrating a method for transmitting data during handover according to an embodiment of the present invention;

fig. 12 is a flowchart illustrating a method for transmitting data during handover according to an embodiment of the present invention;

fig. 13 is a flowchart illustrating a method for transmitting data in a handover process according to an embodiment of the present invention.

Detailed Description

Hereinafter, some terms in the embodiments of the present application are explained to facilitate understanding by those skilled in the art.

(1) In the embodiments of the present application, the terms "network" and "system" are often used interchangeably, but those skilled in the art can understand the meaning.

(2) In the embodiments of the present application, the term "plurality" means two or more, and other terms are similar thereto.

(3) "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

The network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not form a limitation on the technical solution provided in the embodiment of the present application, and as a person of ordinary skill in the art knows that along with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

The embodiment of the invention is applied to an application scene of network switching of a terminal, wherein the application scene relates to the terminal, source network side equipment and target network side equipment. In the switching process of the embodiment of the invention, the terminal keeps data connection with the source network side equipment through the MAC entity or RLC entity which is bound with the PDCP and corresponds to the existing load and carries out data transmission with the source network side equipment through the load; meanwhile, the terminal keeps data connection with the target network side equipment through the MAC entity or the RLC entity which is bound with the same PDCP and corresponds to the newly established bearer, and performs data transmission with the target network side equipment through the bearer. Therefore, in the whole switching layer, the situation that the data connection between the terminal and the source network side equipment is interrupted and the data transmission connection with the target network side equipment is not established can not occur, and meanwhile, the terminal can simultaneously maintain the data transmission between the source network side equipment and the target network side equipment in the switching process, so that the data transmission delay in the terminal switching process can be greatly shortened.

In the embodiment of the present invention, after the terminal receives the handover command with the special instruction information, the PDCP of the terminal maintains a protocol stack architecture of a PDCP combined MAC entity or an RLC entity for the bearer of the source network side device, and the PDCP of the terminal maintains a protocol stack architecture of a PDCP combined MAC entity or an RLC entity for the bearer of the target network side device.

Referring to fig. 1 for the change of the protocol stack architecture of the network side device, in the figure, after the source network side device receives the transmission data, the PDCP layer on the source network side device is transferred to the target network side device through the X2/Xn interface, and then the data transmission is performed through the bottom layers of the source network side device and the target network side device.

For the change of the terminal protocol stack architecture, see fig. 2, the PDCP entity of the terminal simultaneously maintains the MAC entity or RLC entity corresponding to the source network side device and the MAC entity or RLC entity corresponding to the target network side device.

The terminal is a device with a wireless communication function, can be deployed on land, and comprises an indoor or outdoor terminal, a handheld terminal or a vehicle-mounted terminal; can also be deployed on the water surface (such as a ship and the like); and may also be deployed in the air (e.g., airplanes, balloons, satellites, etc.). The terminal may be a mobile phone (mobile phone), a tablet computer (pad), a computer with wireless transceiving function, a Virtual Reality (VR) terminal, an Augmented Reality (AR) terminal, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self driving), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (transportation safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), etc.; but also UEs in various forms, Mobile Stations (MSs), the terminal equipment (terminal device).

The network side device is a device for providing a wireless communication function for the terminal, and includes but is not limited to: a gbb in 5G, a Radio Network Controller (RNC), a network side device B (node B, NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved node B or home node B, HNB), a baseband unit (BBU), a transmission point (TRP), a Transmission Point (TP), a mobile switching center (TP), and the like. The base station in the present application may also be a device that provides the terminal with a wireless communication function in other communication systems that may appear in the future.

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. 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.

To address the above scenario, an embodiment of the present invention provides a schematic structural diagram of a system for transmitting data during a handover process, and as shown in fig. 3 specifically, the system includes:

a terminal 300, configured to maintain data connection with a source network side device and a target network side device through a first data entity corresponding to a bearer and maintain data connection with the source network side device through a second data entity corresponding to the bearer in a handover process, where the data entity is an MAC entity or an RLC entity, and the first data entity and the second data entity are bound to a same PDCP entity; transmitting data with source network side equipment through a first data entity and transmitting data with target network side equipment through a second data entity in the switching process;

a source network side device 301, configured to maintain a data connection with a terminal through a first data entity corresponding to a bearer in a handover process of the terminal, where the terminal simultaneously maintains a data connection with a target network side device; wherein the data entity is a MAC entity or an RLC entity, and the first data entity is bound with the PDCP entity; transmitting data with a terminal through a first data entity;

the target network side device 302 is configured to maintain a data connection with the terminal through a second data entity corresponding to a bearer in a handover process of the terminal, where the terminal simultaneously maintains a data connection with the source network side device; wherein the data entity is a MAC entity or an RLC entity, and the second data entity is bound with the PDCP entity; and transmitting data with the terminal through the second data entity.

The handover process in the embodiment of the present invention refers to a process of performing network handover by the terminal, where the terminal receives a handover instruction sent by the network-side device and sends a handover completion instruction to the terminal.

The following will explain the embodiments of the present invention in detail.

In the switching process, whether the scheme for reducing the data transmission delay in the terminal switching process provided by the embodiment of the invention is adopted or not needs to be determined according to the requirement of the terminal on the data transmission delay.

Optionally, after receiving the indication information including the special handover, the terminal determines that data connection needs to be maintained between the source network side device and the target network side device in the handover process.

In specific implementation, the terminal only needs to determine whether to keep data connection with the source network side device and the target network side device in the current handover process according to whether the received handover instruction includes the indication information of the special handover, and does not need other condition restrictions, so that the terminal can be more widely applied to various network handover environments.

Furthermore, after the terminal needs to maintain data connection with the source network side device and the target network side device in the switching process, the terminal maintains data connection with the source network side device through the first data entity corresponding to the established bearer; and newly establishing a second data entity, and maintaining data connection with the target network side equipment through the second data entity corresponding to the bearer.

In specific implementation, when determining that data connection needs to be maintained with source network side equipment and target network side equipment at the same time, the terminal maintains data connection with the source network side equipment through an MAC entity or an RLC entity bound with a PDCP entity corresponding to an established bearer; and simultaneously, a set of MAC entity or RLC entity bound with the PDCP entity is newly established, and the data connection is kept between the MAC entity or the RLC entity corresponding to the load bearing and the target network side equipment. Thus, in the embodiment of the present invention, the existing established bearer can be used to maintain data connection with the source network side device, and at the same time, only a set of MAC entity or RLC entity corresponding to the target network side device is added on the terminal side, so that the existing layer 2 structure is greatly utilized, thereby not only reducing the data transmission delay time in the handover process, but also making the scheme implementation difficult.

After the MAC entity or the RLC entity bound with the PDCP entity corresponding to the target network side equipment is established, when data needs to be transmitted, the terminal performs data transmission with the source network side equipment through the existing MAC entity or the RLC entity bound with the PDCP entity and performs data transmission with the target network side equipment through the newly established MAC entity or the RLC entity bound with the PDCP entity in the switching process.

Optionally, the terminal reports the first BSR to the source network side device through the first data entity and reports the second BSR to the target network side device through the second data entity in the handover process.

The first BSR includes a first SRB data volume and/or a first DRB data volume, where the first SRB data volume is a data volume of a signaling that the terminal needs to send to a source network side device, and the first DRB data volume is a total amount of all user data that the terminal needs to send or a data volume of part of user data that needs to send;

In the method, the terminal reports the first BSR corresponding to the source network side device through the existing MAC entity or RLC entity bound to the PDCP entity, where the first SRB data volume and/or the first DRB data volume are/is a data volume of a signaling that the terminal needs to send to the source network side device, and the first DRB data volume is a total amount of all user data that the terminal needs to send or a data volume of a part of user data that needs to send, so that the source network side device can configure corresponding resources according to the reported first BSR for data transmission between the terminal and the source network side device.

Meanwhile, the terminal reports a second BSR corresponding to the target network side device through a newly established MAC entity or RLC entity bound to the PDCP entity, where the second BSR includes a second SRB data volume and/or a second DRB data volume, the second SRB data volume is a data volume of a signaling that the terminal needs to send to the target network side device, and the second DRB data volume is a total amount of all user data that the terminal needs to send or a data volume of a part of user data that needs to be sent, so that the source network side device can configure corresponding resources according to the reported first BSR for data transmission between the terminal and the source network device.

The SRB data is signaling, the signaling corresponding to the source network side equipment is first SRB data, and the signaling corresponding to the target network side equipment is second SRB data;

and the data of the DRB is user data, the terminal may have user data transmission with both the source network side device and the target network side device during the handover process, the user data corresponding to the source network side device is first DRB data, and the user data corresponding to the target network side device is second DRB data.

For example, for a handover complete signaling, the signaling needs to be sent to the target network side device by the terminal, in a specific implementation, the terminal needs to calculate a data volume of the signaling and report the data volume corresponding to the signaling to the BSR of the target network side device, and the BSR of the source cell does not need to include the signaling data volume of the SRB.

For example:

1. in the handover process, since the data volume of the DRB may be included in the BSR reports to the source network side device and the target network side device, that is, the terminal may transmit to both the source network side device and the target network side device, the same DRB buffer data volume may be reported at this time, that is, the total amount of all user data to be transmitted is transmitted to the source network side device and the target network side device.

2. In a specific implementation environment, considering that a data connection between a terminal and a source network side device may be disconnected in the near future, only a part of data volume may be reported to the source network side device, where the part of data volume is enough to be transmitted before the source network side device is disconnected, and correspondingly, the data volume reported by the terminal to a target network side device may also be reduced by some, that is, data already transmitted by the source network side device may be temporarily not considered to be transmitted again by the target network side device.

In the data transmission process, when data transmission is performed between the terminal and the network side device, the transmitted data needs to be processed by using the security and header compression context corresponding to the network side device, so as to ensure the security and integrity of the data.

In a specific implementation, in a handover process, the terminal needs to process data transmitted between the terminal and the source network side device by using a security and header compression context corresponding to the source network side device through a PDCP layer, and process data transmitted between the terminal and the target network side device by using a security and header compression context corresponding to the target network side device through the PDCP layer.

In the above process, the terminal needs to process the data transmitted between the source network side device and the destination network side device by using the security and header compression context corresponding to the source network side device through the PDCP layer in the handover process, and processes the data transmitted between the destination network side device and the destination network side device by using the security and header compression context corresponding to the destination network side device through the PDCP layer, that is, the terminal side needs to maintain the security and header compression contexts corresponding to the source network side device and the destination network side device, so that the terminal can simultaneously ensure the security and integrity of the data transmitted between the source network side device and the destination network side device.

In specific implementation, the PDCP entity of the terminal may simultaneously maintain two sets of security and header compression contexts corresponding to the source network side device and the target network side device, so as to simultaneously ensure the security and integrity of data transmitted between the source network side device and the target network side device.

However, when the PDCP entity of the terminal simultaneously maintains two sets of security and header compression contexts corresponding to the source network side device and the target network side device, it may have a relatively high requirement on the capability of the terminal. In view of this, the embodiment of the present invention provides a scheme that a PDCP entity of a terminal only maintains security and header compression context of a set of network side devices at a certain time.

Optionally, the terminal processes, before the set time, data transmitted between the terminal and the source network side device by using the security and header compression context corresponding to the source network side device through the PDCP layer, and processes, after the set time, data transmitted between the terminal and the target network side device by using the security and header compression context corresponding to the target network side device through the PDCP layer.

Further, the set time is one of the following times:

In the method, after the MAC layer of the terminal succeeds in random access to the target network side equipment, the PDCP layer is informed to start resetting and use related parameters of safety and header compression of the target network side equipment; or when the RLC entity or the MAC entity of the target network side equipment receives a first downlink data packet from the terminal, informing the PDCP layer of the terminal side to start resetting and using the related parameters of the safety and the header compression of the target network side equipment; or when the RLC entity or MAC entity of the target network side device receives the first dedicated data scheduling from the target network side device of the terminal, the scheduling resource may be uplink or downlink, notifies the PDCP layer of the terminal side, and starts to reset and use the security and header compression related parameters of the target network side device; or other time point which can indicate that the connection between the terminal and the target network side device is successful, the PDCP layer of the terminal side is informed to start resetting and using the security and header compression related parameters of the target network side device.

For the PDCP entity of the terminal, the above method is equivalent to that at this point, the PDCP of the terminal performs a conventional PDCP re-establishment procedure, retains current values of the SN and various state variables, resets the security and header compression context, and starts operating for subsequent packets using the new security and header compression context.

Meanwhile, for AM (acknowledged mode) service, repeated transmission is performed starting from the first packet that does not receive the RLC positive acknowledgement of the corresponding receiving end or only for the packet that does not receive the RLC positive acknowledgement.

For UM (unacknowledged mode) traffic, transmission starts with the first packet that is not sent.

The PDCP, for RLC SDU (Service Data Unit) Data received at this point in time due to re-establishment, still performs a de-security and de-header compression operation using old security and header compression. And performing the operations of de-security and de-header compression by using new security and header compression for the subsequent data from the target network side equipment.

At the same time, the RLC entity or MAC entity associated with the source network side device also performs a reset operation, sends the buffered out-of-sequence complete RLC SDU data to the PDCP, deletes fragmented data such as other SDU segments, and deletes the associated RLC and MAC entities. That is, the UE is formally switched to the target network device after transmission between the UE and the source network device is disconnected, and performs data transmission between the UE and the target network device using the newly established entity or MAC entity.

In this process, the terminal basically can disconnect data Transmission with the source network side device for the last TTI (Transmission Time Interval), and can perform data Transmission with the target network side device immediately after the next TTI, so that the data interruption delay can be reduced to 0.

Further, considering that the reconstruction of the PDCP entity of the terminal and the immediate transmission of the high data amount to the target network side device may have a high requirement on the real-time processing capability of the layer 2 of the terminal, and there may be a requirement that the capability of some terminals is insufficient to reconstruct the PDCP entity and transmit the high data amount to the target network side device at the same time in the specific implementation, the embodiments of the present invention also provide a corresponding solution.

The first mode is that when the processing capacity of the terminal is not high and data of target network side equipment is scheduled in the switching process, a proper amount of transmission block size is allocated according to the instantaneous processing capacity of the UE only, so that the terminal can process the transmitted data in real time, and the throughput is gradually improved after the processing capacity of the terminal is reserved.

And secondly, the terminal can utilize the security and the header compression context of the target network side equipment to preprocess the data to be transmitted, when the scheduling or the transmission of the target node is judged to be close to success, the terminal can organize the transmission of some preprocessed data to the target network side equipment in advance enough for the transmission of a certain TTI, and when the data authorization arrives, the preprocessed data are directly transmitted to the target node.

The above embodiment gives the case that the security and header compression of the source and target network side devices both need to be reset, which is a relatively common scenario. In addition, there are some special scenarios, where security and/or header compression processing between a source and a target are continuous, which is basically the case where a source network side device and a target network side device are located in different cells under the same gNB (5G Node B, 5G base station) or under the same CU (Control Unit).

In this scenario, the UE processing is slightly different than in the above embodiments. The following cases are distinguished:

when only the security context in the security or header compression context needs to be reset, when the UE processes the transmission data, the source network side device and the target network side device corresponding to the terminal are respectively processed by using their respective security contexts, and for the header compression context that does not need to be reset, the processes are performed normally according to the SN sequence.

When only the header compression context in the security or header compression context needs to be reset, when the UE processes the transmission data, the source network side device and the target network side device corresponding to the terminal respectively adopt their respective header compression contexts to process, and for the security context that does not need to be reset, the processes are normally performed together according to the SN sequencing.

For the case that the security context or the header compression context does not need to be reset, the UE may merge the data from the two different paths according to the existing condition of dual connectivity split (DCsplit) bearer, and only needs to maintain a set of security and header compression parameters, and sequentially process and sequence the data.

Based on the above processing, when the terminal processes the data transmitted between the terminal and the source network side device by using the security and header compression context corresponding to the source network side device through the PDCP layer, and processes the data transmitted between the terminal and the target network side device by using the security and header compression context corresponding to the target network side device through the PDCP layer, the terminal needs to distinguish the transmitted data, and determine whether the data belongs to the source network side device or the target network side device.

Optionally, the terminal determines that the data to be processed belongs to the source network side device or the target network side device according to the bottom layer notification received by the PDCP layer; or

And the terminal determines that the data needing to be processed belongs to the source network side equipment or the target network side equipment through the PDCP layer according to the indication information in the data needing to be processed.

In specific implementation, there are two ways to determine whether the processed data belongs to the source network side device or the target network side device.

One is that the terminal determines that the data to be processed belongs to the source network side device or the target network side device according to the notification of the bottom layer received by the PDCP layer.

In the method, a terminal bottom layer determines that data to be processed belongs to source network side equipment or target network side equipment, transmits a determined result to a PDCP layer, finally determines that the data to be processed belongs to the source network side equipment or the target network side equipment, and then processes the data to be processed by adopting corresponding security and header compression context according to the determined result so as to be correctly transmitted to the corresponding network side equipment.

For example: generally, the source network side device and the target network side device have respective identification information, such as PCI (Physical Cell Identifier), Cell ID (Cell identification) or other configuration, and the base layer can know from which network side device the transmission data to be processed comes from according to the identification information, and inform the network side device to which the PDCP data packet of the UE belongs through interlayer interaction.

The other is that the terminal determines that the data to be processed belongs to the source network side device or the target network side device through the PDCP layer according to the indication information in the data to be processed.

In the method, the network side equipment needs to insert indication information indicating the source of the network side equipment into transmission data in the switching process, after the terminal receives the information and before the terminal processes the information, the PDCP of the terminal determines the attribution of the terminal according to the indication information in the transmission data, and then processes the data according to the determined security and header compression context corresponding to the network side equipment.

For example: the PDCP of the network side device adds extra information in its data packet header to indicate the current security and the version of header compression, for example, 1bit information, where 0 represents the source network side device, and 1 represents the target network side device, or the first source network side device is 0, the network side device to be switched is 1, and the network side device to be switched is still 0 again, and so on.

Further, to avoid switching interlaces frequently for many times, different network side devices may be represented by more bits.

In summary, the PDCP may carry information to distinguish different network devices, so that data packets from different network devices can be distinguished, and the received data is processed using different security and header compression contexts corresponding to the network devices.

In a specific implementation, the source network side device disconnects the data connection maintained with the terminal through the first data entity corresponding to the bearer after determining that the terminal has been switched to the target network side device.

Further, the source network side device determines that the terminal has been switched to the target network side device by part or all of the following ways:

feedback is not received after downlink data is sent to the terminal;

In specific implementation, when the source network side device determines that the basic data transmission service of the terminal cannot be met through various measurement results, or the source network side device does not receive data sent by the terminal after sending uplink authorization to the UE; or there is no feedback message after the downlink data sent to the UE; or when there is no received signal after any uplink transmission configured to the UE, the terminal is determined to have switched to the target network side device and then the data connection maintained with the terminal through the first data entity corresponding to the bearer is disconnected. Therefore, after the terminal is connected to the target network side device, the data connection between the source network side device and the terminal can be closed in time, so that network resources are saved.

In the conventional handover procedure, after sending a handover command to the UE, the source network side device starts forwarding data and transferring SN status to the target network side device. In the process of the design, after the handover command, the UE still maintains data transmission with the source network side device for a period of time, so as to ensure that data of the UE is not interrupted during the period of time when the UE initiates access and waits for scheduling to the target network side device. That is to say, within a period of time after the handover command, the data transmission condition of the source network side device may still be updated, and then the time point of data forwarding and SN state delivery to the target network side device may be delayed backwards, or the content of data forwarding and SN state delivery is pre-determined in consideration of that the source network side device may update the transmission state.

In specific implementation, after the terminal accesses the target network device, data forwarding and/or SN state transfer of the source network side device is performed.

Optionally, the target network side device triggers the source network side device to forward data and/or transmit an SN status after the terminal starts to access the target network side device.

In the method, after the terminal accesses the target network equipment, the target network side equipment triggers the source network side equipment to forward data and/or transmit the SN state, and the source network side equipment receives the triggering instruction and then forwards data and/or transmits the SN state to the target network side equipment.

In the specific implementation process, the earlier the data forwarding time and the SN state transmission time, the more the target network side device starts transmission as soon as possible.

In a specific implementation, the source network side device may further forward data and/or transmit an SN status to the target network side device when a set duration after the handover command is sent reaches.

Therefore, the data forwarding and/or SN (service number) state transmission from the source network side equipment to the target network side equipment can be triggered without waiting for the terminal to access the target network equipment.

However, in the above method, the information of the subsequent transmission status update of the source network side device cannot be reflected in time, and the target network side device may waste resources to transmit the data that the UE has correctly received from the source network side device. Therefore, the performance of the UE and the overhead of the network are a pair of contradictions, and compromise is required. May be determined by an algorithm.

Optionally, the target network side device notifies the source network side device to release the context of the terminal after the terminal accesses the target network side device or the terminal completes handover.

In the method, after the target network side device confirms that the UE has successfully accessed, the target network side device may send the displayed signaling indication to the source network side device, notify the source network side device that the service of the UE may be stopped, and delete the context information related to the UE, so as to release the bearer of the terminal.

As shown in fig. 4, an embodiment of the invention provides a timing chart of a method for transmitting data during handover.

Step 400, the source base station sends a Handover request message to the target base station, where the Handover request instruction is a Dual Connectivity Based Handover instruction (DCB HO indicator (Dual Connectivity Based Handover instruction)));

step 401, the target base station returns a handover request response message (HO request ACK) to the source base station;

step 402, the source base station sends a switching instruction to the terminal, wherein the switching instruction comprises special switching request identification information (HO);

step 403, performing User data transmission (User data) between the terminal and the source base station;

step 405, the source base station sends Data forwarding (Data forwarding) to the target base station;

step 406, the terminal sends a Random Access Preamble to the target base station;

step 407, the target base station sends a random access Response message (RAR, RACH Response random access Response) to the terminal;

step 408, the terminal connects a Reconfiguration Complete message (RRC Connection Reconfiguration Complete) to the target base station RRC (Radio Resource Control);

step 409, the target base station sends a Path switch request message (Path switch request) to an MME (Mobility Management Entity)/AMF (Access and Mobility Management Function);

step 410, carrying out Bearer modification (Bearer modification) on MME/AMF and S-GW (Serving gateway Way)/UPF (User plane function);

step 411, the MME/AMF returns a Path switch request response (Path switch request ack) to the target base station;

step 412, performing User data transmission (User data) between the terminal and the source base station;

step 413, User data transmission (User data) is carried out between the terminal and the target base station;

step 414, the target base station sends a PDCP/RRC success indicator (PDCP/RRC: success indicator) to the terminal;

step 415, the source base station stops data transmission (Stop data transmission) with the terminal;

step 416, the source base station sends SN Status Transfer (SN Status Transfer) to the target base station.

Wherein, there is no inevitable time sequence relationship among the steps 409 to 411, the step 412 and the step 413, and the steps 409 to 411, the step 412 and the step 413 may be executed sequentially or simultaneously.

As shown in fig. 5, a terminal for transmitting data in a first handover procedure according to an embodiment of the present invention includes a processor 500, a memory 501, and a transceiver 502;

the processor 500 is responsible for managing the bus architecture and general processing, and the memory 501 may store data used by the processor 500 in performing operations. The transceiver 502 is used to receive and transmit data under the control of the processor 500.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 500 and various circuits of memory represented by memory 501 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 processor 500 is responsible for managing the bus architecture and general processing, and the memory 501 may store data used by the processor 500 in performing operations.

The processes disclosed in the embodiments of the present invention may be applied to the processor 500, or implemented by the processor 500. In implementation, the steps of the signal processing flow may be implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 500. The processor 500 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof that may implement or perform the methods, steps, and logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 501, and the processor 500 reads the information in the memory 501, and completes the steps of the signal processing flow in combination with the hardware thereof.

Specifically, the processor 500 is configured to read the program in the memory 501 and execute:

Optionally, the processor 500 is further configured to:

after receiving the indication information containing the special handover, determining that data connection needs to be maintained between the source network side device and the target network side device in the handover process.

Optionally, the processor 500 is further configured to:

after data connection with source network side equipment and target network side equipment is required to be maintained in the switching process, the data connection is maintained with the source network side equipment through a first data entity corresponding to the established bearer; and newly establishing a second data entity, and maintaining data connection with the target network side equipment through the second data entity corresponding to the bearer.

Optionally, the processor 500 is specifically configured to:

reporting the first BSR to the source network side equipment through the first data entity and reporting the second BSR to the target network side equipment through the second data entity in the switching process;

Optionally, the processor 500 is further configured to:

when data is transmitted between a first data entity and a source network side device and data is transmitted between a second data entity and a target network side device in a switching process, the data transmitted between the first data entity and the source network side device is processed by utilizing a security and header compression context corresponding to the source network side device through a PDCP layer, and the data transmitted between the source network side device and the target network side device is processed by utilizing the security and header compression context corresponding to the target network side device through the PDCP layer.

Optionally, the processor 500 is specifically configured to:

and after the set time, processing the data transmitted between the source network side device and the target network side device by using the security and header compression context corresponding to the target network side device through the PDCP layer.

Optionally, the set time is one of the following times:

Optionally, the processor 500 is further configured to:

determining that the data needing to be processed belongs to source network side equipment or target network side equipment according to the bottom layer notification received by the PDCP layer; or

And determining that the data needing to be processed belongs to the source network side equipment or the target network side equipment through the PDCP layer according to the indication information in the data needing to be processed.

As shown in fig. 6, a source network side device for transmitting data in a first handover process according to an embodiment of the present invention includes a processor 600, a memory 601, and a transceiver 602;

the processor 600 is responsible for managing the bus architecture and general processing, and the memory 601 may store data used by the processor 600 in performing operations. The transceiver 602 is used to receive and transmit data under the control of the processor 600.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 600 and various circuits of memory represented by memory 601 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 processor 600 is responsible for managing the bus architecture and general processing, and the memory 601 may store data used by the processor 600 in performing operations.

The processes disclosed in the embodiments of the present invention may be applied to the processor 600, or implemented by the processor 600. In implementation, the steps of the signal processing flow may be implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 600. The processor 600 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof that may implement or perform the methods, steps or logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 601, and the processor 600 reads the information in the memory 601 and completes the steps of the signal processing flow in combination with the hardware thereof.

Specifically, the processor 600 is configured to read the program in the memory 601 and execute:

Optionally, the processor 600 is further configured to:

and after the terminal is determined to be switched to the target network side equipment, disconnecting the data connection kept between the first data entity corresponding to the bearer and the terminal.

Optionally, the processor 600 is specifically configured to: determining that the terminal has been switched to the target network side device by part or all of the following ways:

feedback is not received after downlink data is sent to the terminal;

Optionally, the processor 600 is further configured to:

when the set duration after the switching command is sent reaches, data forwarding and/or SN (service number) transmission state is/are carried out on the target network side equipment; and after receiving the trigger of the target network side equipment, forwarding data and/or transmitting SN (service number) state to the target network side equipment.

As shown in fig. 7, a target network side device for transmitting data in a first handover process according to an embodiment of the present invention includes a processor 700, a memory 701, and a transceiver 702;

the processor 700 is responsible for managing the bus architecture and general processing, and the memory 701 may store data used by the processor 700 in performing operations. The transceiver 702 is used to receive and transmit data under the control of the processor 700.

The bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 700, and various circuits, represented by memory 701, 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 processor 700 is responsible for managing the bus architecture and general processing, and the memory 701 may store data used by the processor 700 in performing operations.

The processes disclosed in the embodiments of the present invention may be applied to the processor 700, or implemented by the processor 700. In implementation, the steps of the signal processing flow may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 700. The processor 700 may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof that may implement or perform the methods, steps or logic blocks disclosed in embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 701, and the processor 700 reads the information in the memory 701, and completes the steps of the signal processing flow in combination with the hardware thereof.

Specifically, the processor 700 is configured to read the program in the memory 701 and execute:

Optionally, the processor 700 is further configured to:

and triggering the source network side equipment to forward data and/or transmit SN (service number) state after the terminal starts to access the target network side equipment.

Optionally, the processor 700 is further configured to:

and after the terminal is accessed to the target network side equipment or the terminal is switched, informing the source network side equipment to release the context of the terminal.

As shown in fig. 8, an embodiment of the present invention provides a terminal for transmitting data in a handover process, where the terminal includes:

a connection module 800, configured to maintain data connection with a source network device and a target network device through a first data entity corresponding to a bearer and maintain data connection with the source network device through a second data entity corresponding to the bearer in a handover process, where the data entity is an MAC entity or an RLC entity, and the first data entity and the second data entity are bound to a same PDCP entity;

a data transmission module 801, configured to transmit data with the source network side device through the first data entity and transmit data with the target network side device through the second data entity in the handover process.

Optionally, the connection module 800 is further configured to:

Optionally, the data transmission module 801 is specifically configured to:

Optionally, the data transmission module 801 is further configured to:

Optionally, the data transmission module 801 is specifically configured to:

Optionally, the set time is one of the following times:

Optionally, the data transmission module 801 is further configured to:

As shown in fig. 9, an embodiment of the present invention provides a source network device for transmitting data in a handover process, where the source network device includes:

a connection module 900, configured to maintain a data connection with a terminal through a first data entity corresponding to a bearer in a handover process of the terminal, where the terminal simultaneously maintains a data connection with a target network side device; wherein the data entity is a MAC entity or an RLC entity, and the first data entity is bound with the PDCP entity;

a data transmission module 901, configured to transmit data with a terminal through a first data entity.

Optionally, the connection module 900 is further configured to:

Optionally, the connection module 900 is specifically configured to: determining that the terminal has been switched to the target network side device by part or all of the following ways:

feedback is not received after downlink data is sent to the terminal;

Optionally, the data transmission module 901 is further configured to:

As shown in fig. 10, an embodiment of the present invention provides a target network side device for transmitting data in a handover process, where the target network side device includes:

a connection module 1000, configured to maintain a data connection with a terminal through a second data entity corresponding to a bearer in a handover process of the terminal, where the terminal simultaneously maintains a data connection with a source network side device; wherein the data entity is a MAC entity or an RLC entity, and the second data entity is bound with the PDCP entity;

a data transmission module 1001, configured to transmit data with the terminal through the second data entity.

Optionally, the data transmission module 1001 is further configured to:

Based on the same inventive concept, the embodiment of the present invention further provides a method for sending an uplink probing pilot, and since the method corresponds to the method for sending the uplink probing pilot in the embodiment of the present invention, and the principle of the method for solving the problem is similar to that of the device, the method can be implemented by referring to the device, and repeated details are not repeated.

As shown in fig. 11, an embodiment of the present invention provides a method for transmitting data in a handover process, where the method includes:

step 1100, after a terminal needs to maintain data connection with a source network side device and a target network side device in a handover process, the terminal maintains data connection with the source network side device through a first data entity corresponding to a bearer, and maintains data connection with the target network side device through a second data entity corresponding to the bearer, wherein the data entity is an MAC entity or an RLC entity, and the first data entity and the second data entity are bound to the same PDCP entity;

step 1101, the terminal transmits data with the source network side device through the first data entity and transmits data with the target network side device through the second data entity in the switching process.

Optionally, the method further includes:

and after receiving the indication information containing the special switching, the terminal determines that the terminal needs to keep data connection with the source network side equipment and the target network side equipment in the switching process.

Optionally, after the terminal needs to maintain data connection with the source network side device and the target network side device in the handover process, the method further includes:

maintaining data connection with source network side equipment through a first data entity corresponding to the established bearer; and

and newly establishing a second data entity, and maintaining data connection with the target network side equipment through the second data entity corresponding to the bearer.

Optionally, the terminal transmits data with the source network side device through the first data entity and transmits data with the target network side device through the second data entity in the handover process, including:

the terminal reports the first BSR to the source network side equipment through the first data entity and reports the second BSR to the target network side equipment through the second data entity in the switching process;

Optionally, the terminal transmits data with the source network side device through the first data entity and transmits data with the target network side device through the second data entity in the handover process, further including:

Optionally, the processing, by the terminal, data transmitted between the terminal and the source network side device by using the security and header compression context corresponding to the source network side device through the PDCP layer, and processing, by the PDCP layer, data transmitted between the terminal and the target network side device by using the security and header compression context corresponding to the target network side device includes:

Optionally, the set time is one of the following times:

Optionally, the method further includes:

the terminal determines that the data needing to be processed belongs to source network side equipment or target network side equipment according to the bottom layer notification received by the PDCP layer; or

As shown in fig. 12, an embodiment of the present invention provides a method for transmitting data in a handover process, where the method includes:

step 1200, a source network side device maintains data connection with a terminal through a first data entity corresponding to a bearer in a handover process of the terminal, wherein the terminal simultaneously maintains data connection with a target network side device; wherein the data entity is a MAC entity or an RLC entity, and the first data entity is bound with the PDCP entity;

step 1201, the source network side device transmits data with the terminal through the first data entity.

Optionally, the method further includes:

and the source network side equipment disconnects the data connection kept with the terminal through the first data entity corresponding to the bearer after determining that the terminal is switched to the target network side equipment.

Optionally, the source network side device determines that the terminal has been switched to the target network side device by part or all of the following manners:

feedback is not received after downlink data is sent to the terminal;

Optionally, the method further includes:

when the set duration after the source network side equipment sends the switching command reaches, data forwarding and/or SN (service number) transmission state is carried out on the target network side equipment;

As shown in fig. 13, an embodiment of the present invention provides a method for transmitting data in a handover process, where the method includes:

step 1300, the target network side device maintains data connection with the terminal through a second data entity corresponding to the bearer in the handover process of the terminal, wherein the terminal maintains data connection with the source network side device at the same time; wherein the data entity is a MAC entity or an RLC entity, and the second data entity is bound with the PDCP entity;

step 1301, the target network side device transmits data with the terminal through the second data entity.

Optionally, the method further includes:

and the target network side equipment triggers the source network side equipment to forward data and/or transmit SN states after the terminal starts to access the target network side equipment.

Optionally, the method further includes:

and the target network side equipment informs the source network side equipment to release the context of the terminal after the terminal is accessed to the target network side equipment or the terminal is switched.

The embodiment of the invention also provides a storage medium readable by computing equipment aiming at the method for transmitting data in the switching process, namely, the content is not lost after power failure. The storage medium stores therein a software program comprising program code which, when executed on a computing device, when read and executed by one or more processors, implements the aspects of embodiments of the present invention when transferring data during any of the above handover procedures.

The present application is described above with reference to block diagrams and/or flowchart illustrations of methods, apparatus (systems) and/or computer program products according to embodiments of the application. It will be understood that one block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, and/or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer and/or other programmable data processing apparatus, create means for implementing the functions/acts specified in the block diagrams and/or flowchart block or blocks.

Accordingly, the subject application may also be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.). Furthermore, the present application may take the form of a computer program product on a computer-usable or computer-readable storage medium having computer-usable or computer-readable program code embodied in the medium for use by or in connection with an instruction execution system. In the context of this application, a computer-usable or computer-readable medium may be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A method for transmitting data during handover, the method comprising:

after a terminal needs to keep data connection with source network side equipment and target network side equipment in a switching process, the terminal keeps data connection with the source network side equipment through a first data entity corresponding to a bearer and keeps data connection with the target network side equipment through a second data entity corresponding to the bearer, wherein the data entity is a Media Access Control (MAC) layer entity or a radio link layer control protocol (RLC) entity, and the first data entity and the second data entity are bound with the same Packet Data Convergence Protocol (PDCP) entity;

and the terminal transmits data with the source network side equipment through the first data entity and transmits data with the target network side equipment through the second data entity in the switching process.

2. The method of claim 1, further comprising:

3. The method of claim 1, wherein after the terminal needs to maintain data connection with the source network-side device and the target network-side device in the handover process, the method further comprises:

4. The method of claim 1, wherein the terminal transmits data with the source network-side device through the first data entity and transmits data with the target network-side device through the second data entity during the handover procedure, and the method includes:

the terminal reports the first Buffer Status Report (BSR) to the source network side equipment through the first data entity and reports the second BSR to the target network side equipment through the second data entity in the switching process;

the first BSR includes a first signaling radio bearer SRB data volume and/or a first data radio bearer DRB data volume, where the first SRB data volume is a data volume of a signaling that the terminal needs to send to a source network side device, and the first DRB data volume is a total amount of all user data that the terminal needs to send or a data volume of a part of user data that needs to be sent;

5. The method of claim 1, wherein the terminal transmits data with the source network-side device through the first data entity and transmits data with the target network-side device through the second data entity during the handover procedure, further comprising:

6. The method of claim 5, wherein the terminal processes the data transmitted between the source network side device by using the security and header compression context corresponding to the source network side device through the PDCP layer, and processes the data transmitted between the target network side device by using the security and header compression context corresponding to the target network side device through the PDCP layer, comprising:

7. The method of claim 6, wherein the set time is one of the following:

8. The method of claim 5, further comprising:

9. A method for transmitting data during handover, the method comprising:

10. The method of claim 9, further comprising:

11. The method of claim 10, wherein the source network side device determines that the terminal has been handed over to the target network side device by some or all of the following means:

feedback is not received after downlink data is sent to the terminal;

12. The method of claim 10, further comprising:

and after receiving the trigger of the target network side equipment, the source network side equipment forwards data and/or transmits a Serial Number (SN) state to the target network side equipment.

13. A method for transmitting data during handover, the method comprising:

14. The method of claim 13, further comprising:

15. The method of claim 13, further comprising:

16. A terminal for transmitting data during handover, the terminal comprising: a processor, a memory, and a transceiver;

17. The terminal of claim 16, wherein the processor is further configured to:

18. The terminal of claim 16, wherein the processor is further configured to:

19. The terminal of claim 16, wherein the processor is further configured to:

20. The terminal of claim 16, wherein the processor is further configured to:

21. The terminal of claim 20, wherein the processor is further configured to:

22. The terminal of claim 21, wherein the set time is one of the following:

23. The terminal of claim 20, wherein the processor is further configured to:

24. A source network side device for transmitting data during handover, the source network side device comprising: a processor, a memory, and a transceiver;

25. The source network-side device of claim 24, wherein the processor is further configured to:

26. The source network-side device of claim 25, wherein the processor is specifically configured to: determining that the terminal has been switched to the target network side device by part or all of the following ways:

feedback is not received after downlink data is sent to the terminal;

27. The source network-side device of claim 25, wherein the processor is further configured to:

28. A target network side device for transmitting data in a handover procedure, the target network side device comprising: a processor, a memory, and a transceiver;

29. The target network-side device of claim 28, wherein the processor is further configured to:

30. The target network-side device of claim 28, wherein the processor is further configured to:

31. A terminal for transmitting data during handover, the terminal comprising:

32. A source network side device for transmitting data during handover, the source network side device comprising:

33. A target network side device for transmitting data in a handover procedure, the target network side device comprising: