WO2021027288A1

WO2021027288A1 - Data packet transmission method, terminal device, and network device

Info

Publication number: WO2021027288A1
Application number: PCT/CN2020/081171
Authority: WO
Inventors: 谷柏峰; 宗在峰; 赵倩倩; 姜印清; 魏洪康; 王键; 徐海博
Original assignee: 华为技术有限公司
Priority date: 2019-08-15
Filing date: 2020-03-25
Publication date: 2021-02-18
Also published as: CN112399476A; CN112399476B

Abstract

Disclosed in the present application are a data packet transmission method, a terminal device, and a network device, relating to the technical field of wireless communication, and capable of solving the problem that when a terminal device is handed over from a source base station to a target base station, due to the large delay when the source base station transmits to the target base station information for synchronising the data packet transmission state, data transmission cannot be continued even if the terminal device has been handed over from the source base station to the target base station because the target base station still has not synchronised the data packet transmission state between the source base station and the terminal device. By means of the information for synchronising the data packet transmission state being transmitted by a user plane bearer with a smaller delay, the present solution implements synchronisation of the data packet transmission state of the first base station and the second base station, and reduces the transmission delay of the information for synchronising the data packet transmission state, ensuring the continuous transmission of data packets between the second base station and the terminal device after the terminal device is handed over from the first base station to the second base station.

Description

Data packet transmission method, terminal equipment and network equipment

This application claims the priority of a Chinese patent application filed with the State Intellectual Property Office, the application number is 201910755163.3, and the invention title is "a data packet transmission method, terminal equipment and network equipment" on August 15, 2019. The entire content of the application is approved The reference is incorporated in this application.

Technical field

The embodiments of the present application relate to the field of wireless communication technologies, and in particular, to a data packet transmission method, terminal equipment, and network equipment.

Background technique

With the development of wireless communication technology, the remote deployment of the core network control plane based on Network Function Virtualization (NFV) has become a networking trend. Among them, the remote deployment of the control plane of the core network refers to the separate deployment of the control plane and the user plane of the core network. In this scenario where the control plane of the core network is deployed remotely, the control plane of the core network is usually far away from the user plane. For example, the distance between the network elements on the control plane of the core network and the network elements on the user plane is usually more than 1500 km.

Among them, when the terminal device performs cross-base station handover, the source base station (ie, user plane network element) forwards information (referred to as synchronization information) for synchronizing the transmission state of the data packet to the target base station (ie, user plane network element) through the control plane network element. So that the terminal device can continue data transmission after switching from the source base station to the target base station.

However, since the control plane of the core network is far away from the user plane; therefore, it takes a long time for the source base station (ie, user plane network element) to transmit the aforementioned synchronization information to the target base station (ie, user plane network element) through the control plane network element. During this period, even if the terminal device has been handed over from the source base station to the target base station, the target base station may not have received the aforementioned synchronization information from the source base station. That is, the target base station cannot synchronize the data packet transmission state of the source base station and the terminal device. Therefore, the target base station still cannot transmit data packets with the terminal device, which affects user experience.

Summary of the invention

The embodiment of the present application provides a data packet transmission method, which can solve the problem that when a terminal device is handed over from a source base station to a target base station, the source base station transmits to the target base station information for synchronizing the transmission state of the data packet with a large time delay. The terminal device has been handed over from the source base station to the target base station, and the target base station has not synchronized the data packet transmission status of the source base station and the terminal device, causing the problem that data transmission cannot be continued.

In order to achieve the foregoing objectives, the following technical solutions are adopted in the embodiments of this application:

In a first aspect, a data packet transmission method is provided, which is applied to a process in which a terminal device is handed over from a first base station to a second base station. The method includes: the terminal device determines a first count value of a first uplink data packet; The first uplink data packet is the first uplink data packet that is lost on the first bearer; where the first bearer is the radio bearer between the terminal device and the first base station before handing over from the first base station to the second base station, or the terminal A radio bearer between the device and the second base station after the device switches from the first base station to the second base station; the terminal device sends first information to the second base station, and the first information includes the first count value.

The above-mentioned first bearer is a user plane bearer between the terminal device and the first base station or the second base station. The above-mentioned count value is used for integrity protection and encryption of the data packet. The count value can be composed of two parts: the high-order super frame number and the low-order PDCP sequence number.

In the technical solution provided by the above-mentioned first aspect, the terminal device determines the information about the transmission state of the synchronization data packet, and uses the determined information for the transmission state of the synchronization data packet to be carried by the user plane (between the terminal device and the second base station). Radio bearer) is sent to the second base station to achieve synchronization of the data packet transmission status of the first base station and the second base station, while reducing the transmission delay of information used for data packet transmission status synchronization, and ensuring that the terminal device is switched from the first base station After arriving at the second base station, the second base station and the terminal equipment data packets are continuously transmitted.

In a possible implementation, the terminal device determining the first count value of the first uplink data packet includes: the terminal device receives second information from the first base station, the second information is used to indicate the third information, the The third information includes: the first sequence number of the first uplink data packet or the second count value of the first uplink data packet; the terminal device determines the first count value according to the second information. The terminal device may determine the first count value of the first uplink data packet according to the first sequence number or the second count value of the first uplink data packet lost by the first base station on the first bearer from the first base station. The user plane bearer transmission between the terminal device and the first base station is used to determine the first count value of the first uplink data packet, and the user plane bearer transmission between the terminal device and the second base station is used for data packet transmission status synchronization It can ensure the low-latency transmission of information used for data packet transmission status synchronization.

In a possible implementation manner, the foregoing third information includes the first sequence number of the first uplink data packet; the terminal device determines the first count value according to the second information, including: the terminal device determines the first count value according to the first sequence number and the first sequence number. The superframe number corresponding to a sequence number determines the first count value. The terminal device may determine the first uplink data packet from the first base station according to the first sequence number of the first uplink data packet lost on the first bearer by the first base station and the superframe number corresponding to the first sequence number. One count value.

In a possible implementation manner, the foregoing third information includes the second count value of the first uplink data packet; the terminal device determining the first count value according to the second information includes: the terminal device determines that the second count value is the first Count value. The terminal device may determine the first count value of the first uplink data packet according to the second count value of the first uplink data packet that the first base station loses on the first bearer from the first base station.

In a possible implementation manner, the terminal device determining the first count value of the first uplink data packet includes: the terminal device counts the number of uplink data packets that the terminal device has not received through the first bearer from the first base station confirmation message The value is used as the first count value; or, the terminal device uses the count value of the next uplink data packet to be sent by the terminal device via the first bearer as the first count value. The terminal device may determine the first uplink data packet and the first count value of the first uplink data packet according to whether it has received the confirmation message for the uplink data packet from the first base station. In this way, the terminal device can transmit the information used for the synchronization of the data packet transmission state through the user plane bearer between the terminal device and the second base station, which can ensure low-latency transmission of the information used for the synchronization of the data packet transmission state.

In a possible implementation manner, the above method further includes: the terminal device sends fourth information to the second base station, where the fourth information includes the sequence number and superframe number of the first downlink data packet lost on the first bearer. In this solution, the terminal device can also transmit the count value of the first downlink data packet that the terminal device loses on the first bearer through the user plane bearer between the terminal device and the second base station, for synchronization of the data packet transmission status, It can ensure the low-latency transmission of information used for data packet transmission status synchronization.

In a possible implementation manner, the terminal device sending the first information to the second base station includes: the terminal device sends a handover confirmation message to the second base station, where the handover confirmation message carries the first information. In this solution, the terminal device may carry the first information for the synchronization of the data packet transmission state through the handover confirmation message carried by the user plane, so as to ensure the low-latency transmission of the information for the synchronization of the data packet transmission state.

In a possible implementation manner, the above-mentioned handover confirmation message also carries an identifier of the first bearer. When sending PDCP data packets to the second base station through multiple radio bearers, the second base station can determine the radio bearer used to transmit each PDCP data packet according to the correspondence between the identifier of the first bearer and the PDCP data packet.

In a possible implementation manner, the above method further includes: the terminal device sends a handover confirmation message to the second base station, and the handover confirmation message further carries fourth information. In this solution, the terminal device can carry the first information for the synchronization of the data packet transmission status through the handover confirmation message carried by the user plane, so as to ensure the low-latency transmission of the information for the synchronization of the data packet transmission status.

In a possible implementation manner, the terminal device sending the first information to the second base station includes: the terminal device sends a Packet Data Convergence Protocol PDCP data packet to the second base station, and the PDCP data packet carries the first information. In this solution, the terminal device may carry the first information for synchronization of the transmission state of the data packet through the PDCP data packet carried by the user plane, so as to ensure the low-latency transmission of the information for the synchronization of the transmission state of the data packet.

In a possible implementation manner, the foregoing PDCP data packet also carries the fourth information. In this solution, the terminal device may carry the first information for synchronization of the transmission state of the data packet through the PDCP data packet carried by the user plane, so as to ensure the low-latency transmission of the information for the synchronization of the transmission state of the data packet.

In a possible implementation manner, the above-mentioned PDCP data packet carries type indication information, and the type indication information is used to indicate that the PDCP data packet carries first information. By extending the existing PDCP data packet transmission protocol, the PDCP data packet can carry type indication information for indicating that the PDCP data packet carries the first information, so that the second base station can use the PDCP data packet according to the type indication information. The first information is read in the data packet to improve the efficiency of the second base station to obtain the first information. Among them, the PDCP data packet transmission protocol is used to specify the format of the PDCP data packet.

In a possible implementation manner, the aforementioned PDCP data packet carries type indication information, and the type indication information is used to indicate that the PDCP data packet carries fourth information. By extending the existing PDCP data packet transmission protocol, the PDCP data packet can carry type indication information for indicating that the PDCP data packet carries the fourth information, so that the second base station can obtain information from the PDCP according to the type indication information. The fourth information is read in the data packet to improve the efficiency of the second base station to obtain the fourth information.

In a second aspect, a data packet transmission method is provided, which is applied to a process in which a terminal device is handed over from a first base station to a second base station. The method includes: the second base station receives first information from the terminal device, the first The information includes the first count value of the first uplink data packet; the first uplink data packet is the first uplink data packet lost on the first bearer; wherein, the above-mentioned first bearer is the handover of the terminal equipment from the first base station to the second The radio bearer between the front of the base station and the first base station, or the radio bearer between the terminal device and the second base station after switching from the first base station to the second base station; the above-mentioned second base station determines according to the first information that the second base station is expected to be The sequence number and superframe number of the next uplink data packet received on the first bearer.

According to the technical solution provided by the above second aspect, the second base station can receive the first information from the terminal device through the user plane bearer between the terminal device and the second base station, so as to synchronize the data packet transmission status according to the first information to ensure The low-latency transmission of information used for the synchronization of the transmission state of the data packet ensures the continuous transmission of data packets between the second base station and the terminal device after the terminal device is switched from the first base station to the second base station.

In a possible implementation manner, the above method further includes: the second base station receives a second sequence number from the terminal device and a superframe number corresponding to the second sequence number, and the second sequence number is the first one lost by the terminal device. The sequence number of the downlink data packet; the above-mentioned second base station determines the sequence number and superframe number of the next downlink data packet sent by the second base station to the terminal device according to the second sequence number and the superframe number corresponding to the second sequence number. The second base station can receive the first information from the terminal device through the user plane bearer between the terminal device and the second base station, so as to synchronize the data packet transmission state according to the first information, and ensure the information used for the data packet transmission state synchronization The low-latency transmission ensures that the terminal equipment is switched from the first base station to the second base station and the terminal equipment data packet connection transmission.

In a possible implementation manner, the above method further includes: the second base station receives a first message from the first base station, the first message includes at least one second data packet buffered in the first base station; wherein, the second base station The data packet includes a data packet that the first base station has sent to the terminal device but has not received the confirmation message of the terminal device. The first message also includes the sequence number of the at least one second data packet; the second base station is based on the above The sequence number of at least one second data packet determines the sequence number of the next downlink data packet sent by the second base station to the terminal device. The second base station can receive the information used for data packet transmission status synchronization from the first base station through the user plane bearer between the second base station and the first base station, so as to ensure low-latency transmission of the information used for data packet transmission status synchronization , To ensure that the terminal equipment switches from the first base station to the second base station and the terminal equipment data packet connection transmission.

In a third aspect, a data packet transmission method is provided, which is applied to a process in which a terminal device in a first system is handed over from a first base station to a second base station. The first system includes the aforementioned terminal device, the first base station, and the second base station. A base station, the method includes: the terminal device determines a first count value of a first uplink data packet; the first uplink data packet is the first uplink data packet lost on the first bearer; wherein the first bearer is the terminal The radio bearer between the first base station and the first base station before the device is switched from the first base station to the second base station, or the radio bearer between the above-mentioned terminal device and the second base station after the first base station is switched from the first base station to the second base station; The second base station sends first information, the first information includes a first count value; the second base station receives the first information from the terminal device; the second base station determines based on the first information that the second base station expects to receive on the first bearer The sequence number and superframe number of the next uplink data packet.

In the technical solution provided by the above third aspect, the terminal device determines the information of the synchronization data packet transmission state, and the determined information for the synchronization data packet transmission state is carried by the user plane (the terminal device and the second base station Radio bearer) is sent to the second base station to achieve synchronization of the data packet transmission status of the first base station and the second base station, while reducing the transmission delay of information used for data packet transmission status synchronization, and ensuring that the terminal device is switched from the first base station After arriving at the second base station, the second base station and the terminal equipment data packets are continuously transmitted.

In a possible implementation manner, the above method further includes: the first base station sends second information to the terminal device, the second information is used to indicate the third information, and the third information includes: the first uplink data packet The sequence number or the second count value of the first uplink data packet; the terminal device determining the first count value of the first uplink data packet includes: the terminal device determines the first count value according to the second information. The terminal device may determine the first count value of the first uplink data packet according to the first sequence number or the second count value of the first uplink data packet lost by the first base station on the first bearer from the first base station. The user plane bearer transmission between the terminal device and the first base station is used to determine the first count value of the first uplink data packet, and the user plane bearer transmission between the terminal device and the second base station is used for data packet transmission status synchronization It can ensure the low-latency transmission of information used for data packet transmission status synchronization.

In a possible implementation manner, the above-mentioned third information includes the first sequence number of the first uplink data packet, and the terminal device determines the first count value according to the second information, including: the terminal device according to the first sequence number and The superframe number corresponding to the first sequence number determines the first count value; or, the third information includes the second count value of the first uplink data packet, and the terminal device determines the first count value according to the second information, including: The terminal device determines that the second count value is the first count value. The terminal equipment can be based on the first sequence number of the first uplink data packet that the first base station loses on the first bearer from the first base station and the superframe number corresponding to the first sequence number, or the first base station is in the first The second count value of the first uplink data packet lost on the bearer determines the first count value of the first uplink data packet.

In a possible implementation manner, the terminal device determining the first count value of the first uplink data packet includes: the terminal device indicates that the terminal device has not received the uplink data packet from the first base station confirmation message through the first bearer. The count value is used as the first count value; or, the terminal device uses the count value of the next uplink data packet to be sent by the terminal device through the first bearer as the first count value. The terminal device may determine the first uplink data packet and the first count value of the first uplink data packet according to whether it has received the confirmation message for the uplink data packet from the first base station. In this way, the terminal device can transmit the information used for the synchronization of the data packet transmission state through the user plane bearer between the terminal device and the second base station, which can ensure low-latency transmission of the information used for the synchronization of the data packet transmission state.

In a possible implementation manner, the above method further includes: the terminal device sends fourth information to the second base station, the fourth information including the second sequence number and the superframe number corresponding to the second sequence number, and the second sequence The number is the sequence number of the first downlink data packet lost by the terminal device; the second base station determines the next downlink data packet sent by the second base station to the terminal device according to the second sequence number and the superframe number corresponding to the second sequence number The serial number and superframe number. In this solution, the terminal device can also transmit the count value of the first downlink data packet that the terminal device loses on the first bearer through the user plane bearer between the terminal device and the second base station, for synchronization of the data packet transmission status, It can ensure the low-latency transmission of information used for data packet transmission status synchronization.

In a possible implementation manner, the terminal device sending the first information to the second base station includes: the terminal device sends a handover confirmation message to the second base station, where the handover confirmation message carries the first information. In this solution, the terminal device can carry the first information for the synchronization of the data packet transmission status through the handover confirmation message carried by the user plane, so as to ensure the low-latency transmission of the information for the synchronization of the data packet transmission status.

In a possible implementation manner, the terminal device sending the first information to the second base station includes: the terminal device sends a Packet Data Convergence Protocol PDCP data packet to the second base station, and the PDCP data packet carries the foregoing first information. In this solution, the terminal device may carry the first information for synchronization of the transmission state of the data packet through the PDCP data packet carried by the user plane, so as to ensure the low-latency transmission of the information for the synchronization of the transmission state of the data packet.

In a possible implementation manner, the terminal device sending the fourth information to the second base station includes: the terminal device sending a Packet Data Convergence Protocol PDCP data packet to the second base station, the PDCP data packet carrying the fourth information; or, The terminal device sends a handover confirmation message to the second base station, where the handover confirmation message carries the foregoing fourth information. In this solution, the terminal device may carry the fourth information for synchronization of the data packet transmission state through the PDCP data packet carried by the user plane, so as to ensure the low-latency transmission of the information for the synchronization of the data packet transmission state.

In a possible implementation, the above method further includes: the first base station sends a first message to the second base station, where the first message includes at least one second data packet buffered in the first base station; The data includes a data packet that the first base station has sent to the terminal device but has not received the confirmation message of the terminal device. The first message also includes the sequence number of the at least one second data packet; the second base station is based on the at least one second data packet. The sequence number of the data packet determines the sequence number of the next downlink data packet sent by the second base station to the terminal device. The second base station can receive the information used for data packet transmission status synchronization from the first base station through the user plane bearer between the second base station and the first base station, so as to ensure low-latency transmission of the information used for data packet transmission status synchronization , To ensure that the terminal equipment switches from the first base station to the second base station and the terminal equipment data packet connection transmission.

In a fourth aspect, a terminal device is provided. The terminal device includes: a memory for storing computer program code, the computer program code including instructions; a radio frequency circuit for transmitting and receiving wireless signals; a processor for executing The foregoing instructions enable the terminal device to execute the data packet transmission method in any possible implementation manner of the first aspect.

In a fifth aspect, a second base station is provided. The second base station includes: a memory for storing computer program code, the computer program code including instructions; a radio frequency circuit for transmitting and receiving wireless signals; a processor, By executing the foregoing instructions, the second base station executes the data packet transmission method in any possible implementation manner of the second aspect.

In a sixth aspect, a first system is provided, the first system includes a terminal device, a first base station, and a second base station, and the first system is used to execute the data packet transmission method in any possible implementation manner of the third aspect .

In a seventh aspect, a data packet transmission method is provided, which is applied to a process in which a terminal device is handed over from a first base station to a second base station. The method includes: the first base station determines third information, and the third information includes the first The count value of the data packet, and the count value of the second data packet, the first data packet is the next uplink data packet that the first base station expects to receive from the terminal device through the first bearer, and the second data packet is the first The base station is about to send the next downlink data packet to the terminal device through the first bearer. The first bearer is a radio bearer between the terminal device and the first base station; the first base station uses the user plane General Packet Radio Service Tunneling Protocol GTP The -U tunnel sends a first message to the second base station, and the first message carries the aforementioned third information. Wherein, the aforementioned GTP-U tunnel is a user plane service tunnel between the first base station and the second base station.

According to the technical solution provided by the seventh aspect, the second base station can receive the information from the first base station for data packet transmission status synchronization through the user plane GTP tunnel between the second base station and the first base station, which can ensure that it is used for data Low-latency transmission of information synchronized with packet transmission status.

In a possible implementation manner, the first base station sends the first message to the second base station through the user plane General Packet Radio Service Tunneling Protocol GTP-U tunnel, including: the first base station passes through the communication between the first base station and the second base station. The first message is sent to the second base station through the GTP-U tunnel between the first base station and the data gateway; or, the first base station sends the first message to the data gateway through the GTP-U tunnel between the first base station and the data gateway, so that the data gateway passes through The GTP-U tunnel between the data gateway and the second base station sends the above-mentioned first message to the second base station. The second base station can receive the information used for data packet transmission status synchronization from the first base station through the user plane GTP tunnel between the second base station and the first base station, which can ensure the low time of the information used for data packet transmission status synchronization Delay transmission.

In a possible implementation manner, the foregoing third information is encapsulated in a wireless extension header of the GTP-U protocol of the first message. By extending the existing GTP-U protocol, the first message can carry third information.

In a possible implementation manner, the foregoing wireless extension header further includes first indication information, and the first indication information is used to indicate that the wireless extension header includes the foregoing third information. By extending the existing GTP-U protocol, the first message can carry indication information indicating that the first message carries third information, so that the second base station can read from the first message according to the indication information Taking the third information improves the efficiency of the second base station for obtaining the third information.

In a possible implementation manner, the foregoing first base station sends a plurality of the foregoing first messages to the second base station through a GTP-U tunnel. In order to improve the successful transmission of the information used for data packet transmission status synchronization, the same user plane bearer may be used to transmit the above-mentioned first message multiple times.

In a possible implementation manner, the above method further includes: the first base station sends a first message to the second base station through a mobility management network element, and the mobility management network element is a mobility management network element served by the terminal device. This solution supports the transmission of the first message through multiple bearers, so that the second base station can synchronize the data packet transmission state according to the first message received first, and improve the efficiency of the data packet transmission state synchronization.

In an eighth aspect, a data packet transmission method is provided, which is applied to a process in which a terminal device is handed over from a first base station to a second base station, and the method includes: the second base station uses the user plane General Packet Radio Service Tunneling Protocol GTP- The U tunnel receives the first message from the first base station, the first message includes third information, the third information includes the count value of the first data packet, and the count value of the second data packet, the first data packet is the first A base station expects to receive the next uplink data packet from the terminal device via the first bearer. The second data packet is the next downlink data packet that the first base station will send to the terminal device via the first bearer. The first bearer is the terminal device. The radio bearer between the device and the first base station; the second base station determines, according to the above third information, the count value of the next uplink data packet that the second base station expects to receive from the terminal device on the second bearer, and the second The count value of the next downlink data packet that the base station is about to send to the terminal device through the second bearer; the above-mentioned second bearer means that after the terminal device is handed over from the first base station to the second base station, the terminal device and the second base station A radio bearer corresponding to the first bearer established between the base stations.

According to the technical solution provided by the above eighth aspect, the second base station can receive the information from the first base station for data packet transmission status synchronization through the user plane GTP tunnel between the second base station and the first base station, which can be guaranteed to be used for data Low-latency transmission of information synchronized with packet transmission status.

In a possible implementation manner, the above-mentioned second base station receives the first message from the first base station over the user plane General Packet Radio Service Tunneling Protocol GTP-U tunnel, including: the second base station communicates with the second base station through the first base station. The direct GTP-U tunnel between the two base stations receives the first message from the first base station; or, the second base station receives the first message through the GTP-U tunnel between the second base station and the gateway device; the first message The GTP-U tunnel between the first base station and the gateway device is transmitted from the first base station to the gateway device. The second base station can receive the information used for data packet transmission status synchronization from the first base station through the user plane GTP tunnel between the second base station and the first base station, which can ensure the low time of the information used for data packet transmission status synchronization Delay transmission.

In a possible implementation manner, the above-mentioned wireless extension header further includes first indication information, and the first indication information is used to indicate that the above-mentioned wireless extension header includes third information. By extending the existing GTP-U protocol, the first message can carry indication information indicating that the first message carries third information, so that the second base station can read from the first message according to the indication information Taking the third information improves the efficiency of the second base station for obtaining the third information.

In a possible implementation manner, the foregoing second base station receives multiple first messages from the first base station through the GTP-U tunnel. In order to improve the transmission success rate of the information used for data packet transmission status synchronization, the same user plane bearer may be used to transmit the foregoing first message multiple times.

In a possible implementation manner, the above method further includes: the second base station receives the first message from a mobility management network element, and the mobility management network element is a mobility management network element served by a terminal device. This solution supports the transmission of the first message through multiple bearers, so that the second base station can synchronize the data packet transmission status according to the first message received first, and improve the efficiency of data packet transmission status synchronization. Among them, the mobility management network element is mainly used for access control and mobility management of terminal equipment. In a conventional handover process, the second base station can receive the information used for packet transmission status synchronization from the first base station through the mobility management network element, and the transmission channel is the transmission channel between the user plane network element and the control plane network element.

In a possible implementation, the above method further includes: after the second base station receives the first first message from the first base station, the second base station discards the first message after the first The first message received by the second base station. This solution supports the transmission of the first message through multiple bearers, so that the second base station can synchronize the data packet transmission state according to the first message received first, and improve the efficiency of the data packet transmission state synchronization.

In a ninth aspect, a terminal device is provided. The terminal device includes: a memory for storing computer program code, the computer program code including instructions; a radio frequency circuit for transmitting and receiving wireless signals; and a processor for executing The foregoing instructions enable the terminal device to execute the data packet transmission method in any possible implementation manner of the seventh aspect.

In a tenth aspect, a second base station is provided. The second base station includes: a memory for storing computer program code, the computer program code including instructions; a radio frequency circuit for sending and receiving wireless signals; a processor for By executing the foregoing instructions, the second base station executes the data packet transmission method in any possible implementation manner of the eighth aspect.

In an eleventh aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores computer-executable instructions. When the computer-executable instructions are executed by a processor, the first aspect, the second aspect, the third aspect, and the A data packet transmission method in any possible implementation manner of the seventh aspect or the eighth aspect.

In a twelfth aspect, a chip system is provided. The chip system includes a processor and a memory, and instructions are stored in the memory; when the instructions are executed by the processor, the first, second, and third aspects are implemented. , The data packet transmission method in any possible implementation manner of the seventh aspect or the eighth aspect. The chip system can be composed of chips, or can include chips and other discrete devices.

In a thirteenth aspect, a computer program product is provided, and a computer program product is provided that, when it runs on a computer, makes any one of the first, second, third, seventh, or eighth aspects Data packet transmission method in possible implementations. For example, the computer may be at least one storage node.

Description of the drawings

FIG. 1 is a schematic diagram of an application network service architecture of a data packet transmission method provided by an embodiment of this application;

2 is a schematic diagram of the hardware structure of a terminal device provided by an embodiment of the application;

FIG. 3 is a conventional S1 handover flowchart provided by an embodiment of the application;

FIG. 4 is a schematic diagram of a COUNT structure provided by an embodiment of this application;

5A is a schematic diagram of data packet transmission delay when a terminal device performs cross-base station handover in a game scenario provided by an embodiment of the application;

5B is a schematic diagram of data packet transmission delay when a terminal device performs cross-base station handover in a data download scenario provided by an embodiment of the application;

FIG. 6 is a first flowchart of a data packet transmission method provided by an embodiment of the application;

FIG. 7 is a first flow chart of S1 handover provided by an embodiment of this application;

FIG. 8 is a second flow chart of S1 handover provided by an embodiment of this application;

FIG. 9 is a schematic diagram of a PDCP data packet format provided by an embodiment of the application;

10A is a second flowchart of a data packet transmission method provided by an embodiment of this application;

FIG. 10B is a third flow chart of S1 handover provided by an embodiment of this application;

FIG. 11 is a third flowchart of a data packet transmission method provided by an embodiment of this application;

FIG. 12 is a fourth flowchart of a data packet transmission method provided by an embodiment of this application;

FIG. 13A is a fourth flow chart of S1 handover provided by an embodiment of this application;

FIG. 13B is a fifth flowchart of a data packet transmission method provided by an embodiment of this application;

14 is a diagram of an example of a wireless extension header encoding format of the GTP-U protocol of the first message provided by an embodiment of the application;

FIG. 15 is a fifth flow chart of S1 handover provided by an embodiment of this application;

FIG. 16 is a sixth flow chart of S1 handover provided by an embodiment of this application;

FIG. 17 is a schematic structural diagram of a terminal device provided by an embodiment of this application.

detailed description

The embodiment of the present application provides a data packet transmission method, which is applied to a process in which a terminal device is handed over from a source base station to a target base station. Among them, the embodiment of the present application takes the first base station as the source base station and the second base station as the target base station as an example.

Please refer to FIG. 1, as shown in FIG. 1, which is a schematic diagram of an application network service architecture of a data packet transmission method provided by an embodiment of this application. Among them, Figure 1 uses the network service architecture of the 5th generation (5G) mobile communication system as an example to show the interaction between network functions and entities and the corresponding interfaces. Among them, the 3rd Generation Partnership Project (3GPP) service-based architecture (SBA) of the 5G system mainly includes network functions and entities including: Terminal Equipment (TE) , Access Network (AN) or Radio Access Network (RAN), User Plane Function (UPF), Data Network (DN), Access Management Function (Access Management) Function, AMF), session management function SMF, authentication service function (Authentication Server Function, AUSF), policy control function (Policy Control Function, PCF), application function (Application Function, AF), network slice selection function (Network Slice Selection Function) , NSSF), Unified Data Management (UDM), Network Exposure Function (NEF) and Network Storage Function (NF Repository Function, NRF).

Among them, TE, (R)AN, UPF and DN are generally called user plane network functions and entities (or user plane network elements), and the other parts are generally called control plane network functions and entities (or control plane network elements). ). The control plane network element is defined by 3GPP for processing functions in a network. The control plane network element has 3GPP-defined functional behavior and 3GPP-defined interface. The network function can be used as a network element running on proprietary hardware, or running on Software instances on proprietary hardware, or virtual functions instantiated on a suitable platform, such as implemented on a cloud infrastructure device.

The main functions of each network element are described in detail below.

(R)AN: (R)AN can be AN or RAN. Specifically, (R)AN can be various forms of base stations, such as: macro base station, micro base station, distributed unit-control unit (DU-CU), etc., among which DU-CU is a deployment A device capable of wireless communication with TE in a wireless access network. In addition, the aforementioned base station may also be a wireless controller in a cloud radio access network (CRAN) scenario, or a relay station, access point, vehicle-mounted device, wearable device, or a public land mobile network (public land mobile network) that will evolve in the future. land mobile network, PLMN) network equipment, etc. in the network. (R)AN is mainly responsible for radio resource management, service quality management, data compression and encryption on the air interface side. It should be noted that the names of devices with base station functions may be different in systems that use different wireless access technologies. For example, the base station may be an evolved base station (evolutional NodeB, eNB, or e-NodeB) in Long Term Evolution (LTE), or a gNB in a 5G system.

UPF: Mainly responsible for the forwarding and receiving of user data. UPF can receive downlink data from DN, and then transmit the downlink data to TE through (R)AN. UPF can also receive uplink data from TE through (R)AN, and then forward the uplink data to DN.

DN: For example, DN can be an operator service network, Internet access, or a third-party service network. DN can exchange information with TE through PDU session. Among them, PDU sessions can be divided into multiple types, such as Internet Protocol Version 4 (IPv4), IPv6, and so on.

AMF: Mainly responsible for the processing of control plane messages, such as: access control, mobility management, attach and detach, and gateway selection.

SMF: Mainly used for session management, session establishment, TE IP address allocation and management, etc.

AUSF: Mainly responsible for network security, used to generate keys and realize two-way authentication for TE.

PCF: Mainly used to manage policy rules, manage user subscription information, etc.

UDM: Mainly used for authentication and credit processing, user identification processing, access authorization, registration/mobility management, subscription management and short message management, etc.

NEF: Mainly used for monitoring, billing, etc.

NRF: Mainly used to provide internal/external addressing functions. For the functions of other network elements such as NSSF and AF in FIG. 1, reference may be made to related descriptions in the conventional technology, which will not be repeated here.

Wherein, the TE and (R)AN shown in FIG. 1 can communicate with each other by air interface technology. As shown in Figure 1, N1 is the reference point between TE and AMF, N2 is the reference point between (R)AN and AMF, N3 is the reference point between (R)AN and UPF, and N4 is the reference point between SMF and UPF. The reference point between DN, N6 is the reference point between UPF and DN. As shown in Figure 1, Namf is a service-based interface provided by AMF, Nsmf is a service-based interface provided by SMF, Nausf is a service-based interface provided by AUSF, Nnssf is a service-based interface provided by NSSF, and Nnef is a service-based interface provided by NEF. Service-based interface, Nnrf is the service-based interface provided by NRF, Npcf is the service-based interface provided by PCF, Nudm is the service-based interface provided by UDM, and Naf is the service-based interface provided by AF.

It should be noted that the foregoing Figure 1 is only an example of a network service architecture. The terminal device in the embodiment of the present application may be the TE shown in FIG. 1, and the source base station (ie, the first base station) and the target base station (ie, the second base station) may be R(AN) shown in FIG. The data packet transmission method provided in the embodiments of the present application can also be applied to other network architectures. For example, the network architecture of the fourth-generation (4th-Generation, 4G) mobile communication system. Alternatively, the data packet transmission method of the application embodiment can also be applied to other mobile communication systems developed after the fifth generation, which is not limited in the embodiment of the application.

In the embodiment of this application, the terminal device may be a netbook, a tablet computer, a smart watch, etc. Alternatively, the terminal device can also be other desktop devices, laptop devices, handheld devices, wearable devices, smart home devices, and vehicle-mounted devices with radio communication functions, such as Ultra-mobile Personal Computers (Ultra-mobile Personal Computer). , UMPC), smart cameras, netbooks, personal digital assistants (Personal Digital Assistant, PDA), portable multimedia players (Portable Multimedia Player, PMP), AR (augmented reality)/VR (virtual reality) equipment, aircraft, robots, etc. The embodiment of the present application does not limit the specific type and structure of the terminal device.

Please refer to FIG. 2, as shown in FIG. 2, which is a schematic diagram of the hardware structure of a terminal device provided by an embodiment of this application. As shown in FIG. 2, the terminal device 100 may include a processor 210, a memory (including an external memory interface 220 and an internal memory 221), a universal serial bus (USB) interface 230, a charging management module 240, and a power management module 241, battery 242, antenna 1, antenna 2, mobile communication module 250, wireless communication module 260, audio module 270, speaker 270A, receiver 270B, microphone 270C, earphone jack 270D, sensor module 280, buttons 290, motor 291, indicator 292, a camera 293, a display screen 294, and a subscriber identification module (SIM) card interface 295, etc. The sensor module 280 may include a pressure sensor, a gyroscope sensor, an air pressure sensor, a magnetic sensor, an acceleration sensor, a distance sensor, a proximity light sensor, a fingerprint sensor, a temperature sensor, a touch sensor, an ambient light sensor, a bone conduction sensor, etc.

It can be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on the terminal device 100. In other embodiments of the present application, the terminal device 100 may include more or fewer components than shown, or combine certain components, or split certain components, or arrange different components. The illustrated components can be implemented in hardware, software, or a combination of software and hardware.

The processor 210 may include one or more processing units. For example, the processor 210 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), and an image signal processor. (image signal processor, ISP), controller, video codec, digital signal processor (digital signal processor, DSP), baseband processor, and/or neural-network processing unit (NPU), etc. Among them, the different processing units may be independent devices or integrated in one or more processors.

The controller can generate operation control signals according to the instruction operation code and timing signals to complete the control of fetching and executing instructions.

The processor 210 may also be provided with a memory for storing instructions and data. In some embodiments, the memory in the processor 210 is a cache memory. The memory can store instructions or data that have just been used or recycled by the processor 210. If the processor 210 needs to use the instruction or data again, it can be directly called from the memory. Repeated access is avoided, the waiting time of the processor 210 is reduced, and the efficiency of the system is improved.

In some embodiments, the processor 210 may include one or more interfaces. The interface may include an integrated circuit (inter-integrated circuit, I2C) interface, an integrated circuit built-in audio (inter-integrated circuit sound, I2S) interface, a pulse code modulation (pulse code modulation, PCM) interface, and a universal asynchronous transmitter (universal asynchronous transmitter) interface. receiver/transmitter, UART) interface, mobile industry processor interface (MIPI), general-purpose input/output (GPIO) interface, subscriber identity module (SIM) interface, and / Or Universal Serial Bus (USB) interface, etc.

It can be understood that the interface connection relationship between the modules illustrated in the embodiment of the present invention is merely illustrative and does not constitute a structural limitation of the terminal device 100. In other embodiments of the present application, the terminal device 100 may also adopt different interface connection modes in the foregoing embodiments, or a combination of multiple interface connection modes.

The charging management module 240 is used to receive charging input from the charger. Among them, the charger can be a wireless charger or a wired charger. The power management module 241 is used to connect the battery 242, the charging management module 240 and the processor 210. The power management module 241 receives input from the battery 242 and/or the charge management module 240, and supplies power to the processor 210, the internal memory 221, the display screen 294, the camera 293, and the wireless communication module 260.

The wireless communication function of the terminal device 100 can be realized by the antenna 1, the antenna 2, the mobile communication module 250, the wireless communication module 260, the modem processor, and the baseband processor.

The antenna 1 and the antenna 2 are used to transmit and receive electromagnetic wave signals. Each antenna in the terminal device 100 can be used to cover a single or multiple communication frequency bands. Different antennas can also be reused to improve antenna utilization. For example, antenna 1 can be multiplexed as a diversity antenna of a wireless local area network. In other embodiments, the antenna can be used in combination with a tuning switch.

The mobile communication module 250 can provide a wireless communication solution including 2G/3G/4G/5G and the like applied to the terminal device 100. The mobile communication module 250 may include at least one filter, switch, power amplifier, low noise amplifier (LNA), etc. The mobile communication module 250 can receive electromagnetic waves by the antenna 1, and perform processing such as filtering, amplifying and transmitting the received electromagnetic waves to the modem processor for demodulation. The mobile communication module 250 can also amplify the signal modulated by the modem processor, and convert it into electromagnetic waves for radiation via the antenna 1. In some embodiments, at least part of the functional modules of the mobile communication module 250 may be provided in the processor 210. In some embodiments, at least part of the functional modules of the mobile communication module 250 and at least part of the modules of the processor 210 may be provided in the same device. In the embodiment of the present application, the terminal device 100 may communicate with the first base station 200 and/or the second base station 300 through the mobile communication module 250.

The modem processor may include a modulator and a demodulator. Among them, the modulator is used to modulate the low frequency baseband signal to be sent into a medium and high frequency signal. The demodulator is used to demodulate the received electromagnetic wave signal into a low-frequency baseband signal. Then the demodulator transmits the demodulated low-frequency baseband signal to the baseband processor for processing. The low-frequency baseband signal is processed by the baseband processor and then passed to the application processor. The application processor outputs a sound signal through an audio device (not limited to a speaker 270A, a receiver 270B, etc.), or displays an image or video through the display screen 294. In some embodiments, the modem processor may be an independent device. In other embodiments, the modem processor may be independent of the processor 210 and be provided in the same device as the mobile communication module 250 or other functional modules.

The wireless communication module 260 can provide applications on the terminal device 100 including wireless local area networks (WLAN) (such as Wi-Fi networks), Bluetooth (BT), global navigation satellite system (GNSS) ), frequency modulation (FM), near field communication (NFC), infrared technology (infrared, IR) and other wireless communication solutions. The wireless communication module 260 may be one or more devices integrating at least one communication processing module. The wireless communication module 260 receives electromagnetic waves via the antenna 2, frequency modulates and filters the electromagnetic wave signals, and sends the processed signals to the processor 210. The wireless communication module 260 may also receive the signal to be sent from the processor 210, perform frequency modulation, amplify it, and convert it into electromagnetic wave radiation via the antenna 2.

In some embodiments, the antenna 1 of the terminal device 100 is coupled with the mobile communication module 250, and the antenna 2 is coupled with the wireless communication module 260, so that the terminal device 100 can communicate with the network and other devices through wireless communication technology. The wireless communication technology may include long term evolution (LTE), New Radio (NR), BT, GNSS, WLAN, NFC, FM, and/or IR technologies, etc.

The terminal device 100 implements a display function through a GPU, a display screen 294, and an application processor. The GPU is a microprocessor for image processing, connected to the display 294 and the application processor. The GPU is used to perform mathematical and geometric calculations for graphics rendering. The processor 210 may include one or more GPUs that execute program instructions to generate or change display information.

The display screen 294 is used to display images, videos, etc. The display screen 294 includes a display panel. In some embodiments, the terminal device 100 may include one or N display screens 294, and N is a positive integer greater than one.

The terminal device 100 may implement a shooting function through an ISP, a camera 293, a video codec, a GPU, a display screen 294, and an application processor. The ISP is used to process the data fed back by the camera 293. The camera 293 is used to capture still images or videos. In some embodiments, the terminal device 100 may include 1 or N cameras 293, and N is a positive integer greater than 1. Digital signal processors are used to process digital signals. In addition to digital image signals, they can also process other digital signals. For example, when the terminal device 100 selects a frequency point, the digital signal processor is used to perform Fourier transform on the energy of the frequency point.

The external memory interface 220 may be used to connect an external memory card, such as a Micro SD card, to expand the storage capacity of the terminal device 100. The external memory card communicates with the processor 210 through the external memory interface 220 to realize the data storage function.

The internal memory 221 may be used to store computer executable program code, the executable program code including instructions. The internal memory 221 may include a storage program area and a storage data area. Among them, the storage program area can store an operating system, at least one application program (such as a sound playback function, an image playback function, etc.) required by at least one function. The data storage area can store data (such as audio data, phone book, etc.) created during the use of the terminal device 100. In addition, the internal memory 221 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, a universal flash storage (UFS), etc. The processor 210 executes various functional applications and data processing of the terminal device 100 by running instructions stored in the internal memory 221 and/or instructions stored in a memory provided in the processor.

The terminal device 100 can implement audio functions through an audio module 270, a speaker 270A, a receiver 270B, a microphone 270C, a headset interface 270D, and an application processor. For example, music playback, recording, etc.

The button 290 includes a power button, a volume button, and so on. The button 290 may be a mechanical button. It can also be a touch button. The motor 291 can generate vibration prompts. The indicator 292 can be an indicator light, which can be used to indicate the charging status, power change, and can also be used to indicate messages, missed calls, notifications, and so on. The SIM card interface 295 is used to connect to the SIM card. The SIM card can be inserted into the SIM card interface 295 or pulled out from the SIM card interface 295 to achieve contact and separation with the terminal device 100.

The data packet transmission methods provided in the embodiments of the present application can all be implemented in a terminal device having a hardware structure as shown in FIG. 2 or a terminal device having a similar structure.

It should be noted that the embodiments of this application can be applied to the cross-base station handover process in the remote deployment scenario of the core network control plane, or to other scenarios where the data interaction between the user plane and the data plane takes a long time. The specific network deployment scenario is not limited.

Wherein, the cross-base station handover in the embodiment of the present application may be a cross-base station handover between different systems. For example, the terminal device 100 is handed over from the first base station (ie the source base station) of the 4G LTE system to the second base station (ie, the target base station) of the 5th-Generation New Radio (5G NR) system of the fifth-generation mobile communication system.

Alternatively, the cross-base station handover may also be the cross-base station handover within the system. For example, the terminal device 100 switches from the first base station (ie, the source base station) of the 4G LTE system to the second base station (ie, the target base station) of the 4G LTE system. Among them, S1 is the reference point between the base station and the service gateway (SGW). The cross-base station handover of the terminal device 100 in the 4G LTE system may be referred to as S1 handover. For another example, the terminal device 100 switches from the first base station of the 5G NR system (that is, the source base station) to the second base station of the 5G NR system (that is, the target base station). Among them, N2 is the reference point between the base station and the AMF. The cross-base station handover of the terminal device 100 in the 5G NR system may be referred to as N2 handover. Of course, the cross-base station handover may also be other types of cross-base station handover, which is not limited in the embodiment of the present application.

Exemplarily, the handover of the terminal device 100 across base stations may be due to excessive (e.g., the timing advance (TA) of the serving cell is greater than the preset TA threshold, and the average value of the uplink quality of the serving cell within a certain period of time is less than The preset uplink quality threshold and the average value of the downlink quality of the serving cell within a certain period of time are less than the preset downlink quality threshold, and the level of the terminal device 100 suddenly drops below the preset level threshold during a call , The receiving level of the terminal equipment is greater than or equal to the preset level threshold, but the transmission quality is lower than the preset quality threshold or the system signaling traffic of the serving cell is greater than the preset load threshold. Among them, the terminal equipment 100 spans the base station The switching trigger conditions include but are not limited to the above conditions, which are not limited in the embodiment of the present application.

In order to facilitate those skilled in the art to understand the principles and effects of the methods in the embodiments of the present application, the embodiments of the present application here take S1 handover as an example to briefly introduce the cross-base station handover process of the terminal device 100 in the conventional technology.

Assume that the terminal device 100 resides in a cell managed by the first base station 200. The terminal device 100 may receive downlink user plane data from a packet data network gateway (Packet Data Network Gateway, PDN GW). As shown in FIG. 3, the handover process of the terminal device 100 from the first base station 200 to the second base station 300 may include: the first stage: the handover decision stage, the second stage: the handover request stage, and the third stage: data packet transmission status Synchronization phase and fourth phase: the communication phase after S1 handover.

Among them, the first stage: the handover decision stage may include S301; the second stage: the handover request stage may include S302-S309a; the third stage: the data packet transmission state synchronization stage may include S310-S311a/S311b. The fourth stage: the communication stage after S1 handover, including S312 and other processes. Among them, the detailed description of the communication stage after S1 handover can refer to the conventional technology, the terminal device completes the communication process after S1 handover.

S301. The first base station 200 decides to perform handover of the terminal device 100 based on S1.

S302. The first base station 200 sends a handover request to a first mobility management entity (Mobility management entity, MME) 210.

S303. The first MME 210 selects a suitable target MME, and sends a forward relocation request to the MME (such as the second MME 310).

S304a. The second MME 310 sends a session establishment request to a second service gateway (service gateway, SGW) 320. It is used to request the second SGW 320 to allocate a user plane General Packet Radio Service Tunneling Protocol (GPRS Tunneling Protocol User Plane, GTP-U) address and a tunnel endpoint identifier (Tunnel Endpoint Identifier, TEID).

S304b. The second SGW 320 sends a session establishment response to the second MME 310. Wherein, the session establishment response includes the GTP-U allocated by the second SGW 320 to the second SGW 320 and the corresponding TEID.

S305a. The second MME 310 sends a handover command to the second base station 300.

S305b. The second base station 300 sends a handover command confirmation to the second MME 310.

S306a. The second MME 310 sends a request to establish an independent data forwarding channel to the second SGW 320.

S306b. The second SGW 320 sends a response to the request for establishing an independent data forwarding channel to the second MME 310.

S307. The second MME 310 sends a forward relocation request response to the first MME 210.

S308a. The first MME 210 sends a request to establish an independent data forwarding channel to the first SGW 220.

S308b. The first SGW 220 sends a response to the request for establishing an independent data forwarding channel to the first MME 210.

S309. The first MME 210 sends a handover command (Handover Command) to the first base station 200. It is used to indicate the establishment of an independent data forwarding channel between the first base station 200 and the second base station 300.

S309a. The first base station 200 sends a handover command to the terminal device 100.

S310-S310c and the first base station 200 send the Evolved Packet System Bear (EPS bear) packet data convergence protocol (Packet Data Convergence Protocol, PDCP) to the second base station 300 via the first MME 210 and the second MME 310, respectively ) Data packet transmission status.

S311a/S311b: The first base station 200 sends the direct forwarding data to the second base station 300. The directly forwarded data includes the downlink data buffered by the first base station 200.

S312. After the terminal device 100 synchronizes to the second base station 300, the terminal device 100 sends a handover confirmation (Handover Confirm) message to the second base station 300.

Among them, in the steps S310-S310c shown in FIG. 3, the PDCP data packet transmission status sent by the first base station 200 to the second base station 300 is used to indicate but not limited to at least one of the following: The count value COUNT of the last downlink data packet sent by 100 and the COUNT of the last uplink data packet that the first base station 200 has received from the terminal device 100.

Among them, COUNT is used for integrity protection and encryption of data packets. Exemplarily, in the LTE system, the PDCP layer allocates a 32-bit digital number, namely COUNT, to each data packet.

As shown in Figure 4, the COUNT can be composed of two parts: a high-order Hyper Frame Number (HFN) and a low-order PDCP serial number (Serial Number, SN). The length of the PDCP SN is configured by the upper layer. For example, the length of the PDCP SN can be 5 bits, 7 bits, or 12 bits.

The two parties in communication (for example, the terminal device 100 and the second base station 300) can save the same HFN in advance before data transmission, and the sender uses COUNT to encrypt the data packet, and then sends the encrypted data packet and the SN of the data packet To the receiving end. After the receiving end analyzes the SN of the data packet, it can form a COUNT with the SN and the HFN saved by the receiving end, and then use the COUNT to decrypt the data packet.

The length of the COUNT can be obtained by the second base station 300 from the first base station 200. For example, the second base station 300 obtains the length of the COUNT through S310 or S311a/S311b as shown in FIG. 3. Alternatively, the second base station 300 may also preconfigure the length of the aforementioned COUNT, which is not limited in this embodiment.

Therefore, after the terminal device 100 is handed over from the first base station 200 to the second base station 300, the COUNT of the uplink data packet to be transmitted between the terminal device 100 and the second base station 300 needs to be determined, which is used to set the state machine of the receiving end according to the above COUNT. . Exemplarily, the Rx_Deliv and Rx_Next of the receiving end state machine of the second base station 300 may be set to the aforementioned COUNT: [HFN, SN]. To know the COUNT of the uplink data packet to be transmitted between the terminal device 100 and the second base station 300, it is necessary to determine the PDCP data packet transmission state between the terminal device 100 and the first base station 200.

However, it is understandable that in scenarios such as remote deployment of the control plane of the core network, since the control plane network elements of the core network are too far away from the user plane network elements, the first base station 200 passes through the first MME 210 and the second MME. The process of 310 sending the PDCP data packet transmission status (S310-S310c shown in FIG. 3) to the second base station 300 will take a long time. Therefore, even if the terminal device 100 is successfully handed over from the first base station 200 to the second base station 300, the second base station 300 cannot perform data packet transmission with the terminal device 100. Or, it may cause the second base station 300 to fail to successfully connect the data packet transmission state of the first base station 200 and the terminal device 100 to perform data transmission with the terminal device 100.

For some scenes, for example, data download scenes or game scenes. When the terminal device 100 is handed over from the first base station 200 to the second base station 300, the second base station 300 may not be able to synchronize the transmission of the data packets of the first base station 200 and the terminal device 100 due to the excessive delay of the data packet transmission state status. Therefore, the second base station 300 may not be able to successfully connect the data packet transmission state of the first base station 200 and the terminal device 100 to perform data transmission with the terminal device 100. Furthermore, in the above-mentioned data downloading scene, data downloading may be interrupted or the game will be stuck in the game scene, which affects the user experience.

Exemplarily, as shown in FIG. 5A, a schematic diagram of data packet transmission delay when the terminal device 100 performs cross-base station handover in a game scenario provided in this embodiment of the application. In the game scenario, due to the long delay of the PDCP data packet transmission state synchronization process when the terminal device 100 switches from the first base station 200 to the second base station 300, the terminal device 100 takes a long time (as shown in FIG. 5A). Δt ₁ and Δt ₂ ), the transmission delay of the data packet is too large. In a game scenario, the terminal device 100 is a schematic diagram of the time delay of the PDCP data packet transmission state synchronization process when the terminal device 100 performs cross-base station handover.

As another example, FIG. 5B is a schematic diagram of the data packet transmission delay when the terminal device 100 performs cross-base station handover in the data download scenario provided in this embodiment of the application. As shown in FIG. 5B, due to the long delay of the PDCP data packet transmission state synchronization process when the terminal device 100 is handed over from the first base station 200 to the second base station 300, the terminal device 100 takes a long time (as shown in FIG. 5B). Δt ₃ ), the transmission delay of the data packet is too large.

In order to solve the above-mentioned problem of excessive transmission delay of the data packet transmission status, in the embodiment of the present application, the information used to synchronize the data packet transmission status may be carried on a path with a shorter time delay for transmission. In this way, the time delay during the transmission of the data packet transmission state can be reduced, and the continuous transmission of the data packet after the terminal device is successfully switched.

Example 1:

In this embodiment, the first base station 200 may send information for synchronizing the transmission state of the data packet to the terminal device 100, and the terminal device 100 may indicate to the second base station the SN of the uplink data packet to be received, so as to realize the first base station 200 is synchronized with the data packet transmission state of the second base station 300. In other words, the above-mentioned information for synchronizing the transmission state of the data packet can be transmitted through the user plane network element (the first base station 200 and the terminal device 100), which can reduce the transmission delay of the transmission state of the data packet.

In the following, a data packet transmission method provided in an embodiment of the present application will be described in detail with reference to the accompanying drawings. As shown in FIG. 6, a data packet transmission method provided by an embodiment of the present application may include:

S601. The terminal device 100 determines the first COUNT of the first uplink data packet.

In some embodiments, the terminal device 100 may determine the first COUNT of the first uplink data packet based on the received second information from the first base station 200.

The second information is used to indicate third information, and the third information includes: the first SN of the first uplink data packet or the second COUNT of the first uplink data packet. The first uplink data packet is the first uplink data packet lost on the first bearer. The first bearer is a radio bearer used for data packet transmission between the terminal device 100 and the first base station 200 before handing over from the first base station 200 to the second base station 300. Or a radio bearer used for data packet transmission between the terminal device 100 and the second base station 300 after switching from the first base station 200 to the second base station 300.

In the embodiment of the present application, the first uplink data packet is the first uplink data packet lost on the first bearer. It can be understood that the uplink data packet lost on the first bearer is the next uplink data packet that the terminal device 100 will resend on the first bearer.

In this embodiment of the present application, the second information may include: SN and HFN of all uplink data packets that the first base station 200 has successfully received from the terminal device 100. For example, the second information includes: COUNT [1, 31] and [1, 33] of data packets that the first base station 200 has successfully received from the terminal device 100. It means that the first base station 200 has successfully received the uplink data packets with SNs of 31 and 33 from the terminal device 100, and the second information may indicate: the first SN of the first uplink data packet is 32, or the first uplink data packet The second COUNT value of the data packet is [1, 32].

Alternatively, the second information may include: COUNT[1, 32] of the last data packet that the first base station 200 has successfully received from the terminal device 100. It means that the first base station 200 has successfully received all the uplink data packets with SN before 32 from the terminal device 100, then the second information may indicate: the first SN of the first uplink data packet is 32, or the first uplink data The second COUNT of the packet is [1, 32].

In some embodiments, the terminal device 100 may receive the second information from the first base station 200 through a handover command (Handover Command). As shown in S709a in FIG. 7, the message is a handover command, and the handover command carries second information.

Further, the handover command may also carry the address of the second base station 300, which is used by the terminal device 100 to establish a radio bearer between the terminal device 100 and the first base station 200 according to the address of the first base station 200.

In other embodiments, as shown in S810 in FIG. 8, the terminal device 100 may also separately receive the PDCP data packet from the first base station 200. Wherein, the PDCP data packet carries the second information.

As shown in S710 in FIG. 7 and S811 in FIG. 8, the terminal device 100 determines the first COUNT of the first uplink data packet according to the second information. Exemplarily, if the second information includes: COUNT[1,31] and [1,32] of the data packet that the first base station 200 has successfully received from the terminal device 100, then the terminal device 100 may determine the first data packet according to the second information. The first uplink data packet lost on a bearer is an uplink data packet with SN of 33 and HFN of 1.

Among them, when determining the HFN of the data packet, it is necessary to consider the problem of SN crossing the boundary. Taking the SN length of 8 bits as an example, if the COUNT of the data packet that the first base station 200 has successfully received from the terminal device 100 sent by the terminal device 100 is [2,255], then the second base station 300 can determine that the first bearer is missing The first uplink data packet of SN is 0 and HFN is 3.

In some embodiments, if the second information indicates the first SN of the first uplink data packet. The terminal device 100 may determine the first COUNT according to the first SN and the HFN corresponding to the first SN. That is, the first COUNT is: [HFN corresponding to the first SN, the first SN].

In other embodiments, if the second information indicates the second COUNT of the first uplink data packet. The terminal device 100 may determine that the second COUNT is the first COUNT.

It should be noted that the terminal device 100 may also determine the first COUNT of the first uplink data packet lost on the first bearer according to whether it receives the confirmation message of the uplink data packet from the base station. Specifically, the terminal device 100 may use the COUNT of the uplink data packet of the confirmation message from the first base station 200 that the terminal device 100 does not receive through the first bearer as the first COUNT. Alternatively, the terminal device 100 may use the COUNT of the next uplink data packet to be sent by the terminal device 100 via the first bearer as the first COUNT. It is understandable that the first COUNT determined by the terminal device 100 is used to identify the SN and HFN of the uplink data packet that the terminal device 100 will send to the second base station 300 on the first bearer.

S602. The terminal device 100 sends the first information to the second base station 300.

The first information includes the first COUNT, that is, the first information includes the SN and HFN of the uplink data packet that the terminal device 100 will send to the second base station 300 on the first bearer.

In some embodiments, the terminal device 100 may encapsulate the first information in a PDCP data packet and send it to the second base station 300.

Exemplarily, as shown in FIG. 9, it is a schematic diagram of a PDCP data packet format provided in an embodiment of this application. As shown in Figure 9, D/C is used to identify the PDCP data packet type. If D/C is set to 0, it indicates that the PDCP data packet is used to transmit control information. Among them, R is a reserved bit. In addition, in FIG. 9, the COUNT length is 32 as an example. Therefore, the PDCP data packet carries 4 COUNTs each having a length of 8 bits.

In some embodiments, as shown in S711 in FIG. 7, the terminal device 100 may send the first information to the second base station 300 through a handover confirmation message. The handover confirmation message is used to indicate the successful handover of the terminal device 100 from the first base station 200 to the second base station 300, and the handover confirmation message carries a PDCP data packet, and the PDCP data packet carries the first information.

Further, the handover confirmation message may also carry the identifier of the first bearer. Wherein, the identifier of the first bearer has a corresponding relationship with the PDCP data packet: (the identifier of the first bearer, the PDCP data packet). The corresponding relationship between the identifier of the first bearer and the PDCP data packet is used when the terminal device 100 sends PDCP data packets to the second base station 300 through multiple radio bearers, the second base station 300 may determine to transmit each PDCP data according to the corresponding relationship The radio bearer used by the packet.

In other embodiments, when the terminal device 100 sends the first information to the second base station 300 through the handover confirmation message, the terminal 100 may carry the first information through an extended field in the handover confirmation message.

In other embodiments, as shown in S812 in FIG. 8, the terminal device 100 may also directly send the PDCP data packet carrying the first information to the second base station 300.

If the terminal device 100 directly sends the PDCP data packet carrying the first information to the second base station 300, in some embodiments, the PDCP data packet may also include type indication information. As shown in the PDU type in FIG. 9, the type indication information is used to indicate that the PDCP data packet of the second base station 300 carries the first information.

S603. The second base station 300 determines, according to the first information, the SN and HFN of the next uplink data packet that the second base station 300 expects to receive on the first bearer.

Among them, the second base station 300 expects the SN of the next uplink data packet received on the first bearer to be the SN of the first COUNT, and the second base station 300 expects the HFN of the next uplink data packet received on the first bearer to be the first HFN of COUNT.

Exemplarily, if the first COUNT is [2, 33], the SN of the next uplink data packet that the second base station 300 expects to receive on the first bearer is 33, and the HFN is 2.

In some embodiments, as shown in FIG. 10A, the data packet transmission method of Embodiment 1 of the present application may further include:

S604-1. The terminal device 100 determines fourth information.

Wherein, the fourth information includes the SN and HFN of the first downlink data packet lost on the first bearer.

In the embodiment of the present application, the terminal device 100 may determine the fourth information according to the received downlink data packet from the first base station 200 and the SN and HFN of each downlink data packet.

Exemplarily, the terminal device 100 has successfully received downlink data packets with COUNTs of [0, 3], [0, 4], [0, 5], and [0, 6]. Then, the terminal device 100 may determine that the fourth information is [0, 7] according to the above information, that is, the COUNT of the first downlink data packet lost on the first bearer is [0, 7].

Wherein, the terminal device 100 may determine the second information and the fourth information at the same time, or may determine the fourth information before determining the second information, or may determine the fourth information after determining the second information (S1012 in FIG. 10B), The embodiments of this application do not limit this.

S605-1. The terminal device 100 sends fourth information to the second base station 300.

It should be noted that the fourth information may be sent to the second base station 300 by the terminal device 100 together with the first information. It can also be sent to the second base station 300 by the terminal device 100 alone. The terminal device 100 may also perform S605-1 after S602. Alternatively, the terminal device 100 may also perform S605-1 before S602, which is not limited in the embodiment of the present application.

In some embodiments, the fourth information may be sent by the terminal device 100 to the second base station 300 through a handover confirmation message.

In other embodiments, as shown in S1012 in FIG. 10B, the fourth information may also be sent by the terminal device 100 to the second base station 300 by directly sending PDCP data packets.

If the fourth information is sent by the terminal device 100 to the second base station 300 by directly sending a PDCP data packet, in some embodiments, the PDCP data packet may also carry type indication information. The type indication information is used to indicate that the PDCP data packet of the second base station 300 carries the fourth information. Regarding the structure of the PDCP data packet, reference may be made to the schematic diagram of the PDCP data packet format shown in FIG. 9, which will not be repeated here.

S606-1: The second base station 300 determines the SN of the next downlink data packet sent by the second base station 300 to the terminal device 100 according to the fourth information.

Exemplarily, the fourth information includes that the COUNT is [4, 7], that is, the COUNT of the first downlink data packet lost on the first bearer is [4, 7]. Then the second base station 300 can determine that the SN of the next downlink data packet sent by the second base station 300 to the terminal device 100 is 7.

Alternatively, in other embodiments, as shown in FIG. 11, the data packet transmission method of Embodiment 1 of the present application may further include:

S604-2. The second base station 300 receives the first message from the first base station 200.

Wherein, the first message includes at least one second data packet buffered in the first base station 200 and the SN of the at least one second data packet. The second data packet includes a data packet that the first base station 200 has sent to the terminal device 100 but has not received the confirmation message of the terminal device 100.

In some embodiments, the first message further includes at least one downlink data packet buffered in the first base station 200 and not sent by the first base station 200 to the terminal device 100, and the SN of the at least one downlink data packet.

S605-2. The second base station 300 determines the SN of the next downlink data packet sent by the second base station 300 to the terminal device 100 according to the first message.

Exemplarily, the first message includes the SN 7 of the data packet that the first base station 200 has sent to the terminal device 100 but has not received the confirmation message of the terminal device 100, and the downlink data packet corresponding to the SN 7. Then the second base station 300 can determine that the SN of the next downlink data packet sent by the second base station 300 to the terminal device 100 is 7.

In some embodiments, if every downlink data packet sent by the first base station 200 to the terminal device 100 has received a confirmation message from the terminal device 100, the second base station 300 can determine that the second base station 300 sends the terminal device 100 The next downlink data packet is the first data packet among at least one downlink data packet that the first base station 200 has not sent to the terminal device 100.

Example 2:

In this embodiment, the first base station 200 may send information for synchronizing the transmission state of the data packet to the second base station 300 through the GTP-U tunnel, for the second base station 300 to realize the data packet communication with the terminal device 100 according to the information. The transmission status is synchronized. In other words, the aforementioned information for synchronizing the transmission state of the data packet can be transmitted from the first base station 200 to the second base station 300 through the GTP-U tunnel with a small time delay, which reduces the transmission delay of the data packet transmission state.

In the following, a data packet transmission method provided in an embodiment of the present application will be described in detail with reference to the accompanying drawings. As shown in FIG. 12, the data packet transmission method of the embodiment of the present application may include:

S1201. The first base station 200 determines third information.

Wherein, the third information includes the COUNT of the first data packet and the COUNT of the second data packet. The first data packet is the first data packet that the first base station 200 has not yet received from the terminal device 100 on the first bearer. The second data packet is the next data packet that the first base station 200 will send to the terminal device 100 on the first bearer. The first bearer is a radio bearer between the terminal device 100 and the first base station 200.

S1202. The first base station 200 sends a first message carrying third information to the second base station 300 through the GTP-U tunnel.

In some embodiments, as shown in S1311a in FIG. 13A, the first base station 200 may send the first base station carrying the third information to the second base station 300 through the GTP-U tunnel between the first base station 200 and the second base station 300. news.

In other embodiments, the first base station 200 may also sequentially pass through the GTP-U tunnel between the first base station 200 and the data gateway, and the GTP-U tunnel between the data gateway and the second base station 300, to send to the second base station 300 The first message that carries the third information.

Wherein, the first base station 200 and the second base station 300 may serve the same data gateway (such as data gateway A). In this case, the first base station 200 can pass through the GTP-U tunnel between the first base station 200 and the data gateway A, and the GTP-U tunnel between the data gateway A and the second base station 300 in turn, to the second The base station 300 sends the first message that carries the third information.

Alternatively, the first base station 200 and the second base station 300 may serve different data gateways. For example, the first base station 200 serves the first SGW 220, and the second base station 300 serves the second SGW 320. In this case, as shown in S1311b in FIG. 13B, the first base station 200 may send the first message to the first SGW 220 through the GTP-U tunnel between the first base station 200 and the first SGW 220, so that the first The SGW 220 sends the first message to the second SGW 320 through the GTP-U tunnel between the first SGW 220 and the second SGW 320, and makes the second SGW 320 pass through the GTP-U between the second SGW 320 and the second base station 300 The tunnel sends the first message carrying the third information to the second base station 300.

In some embodiments, the first base station 200 may encapsulate the third information in a wireless extension header of the GTP-U protocol of the first message and send it to the second base station 300. Exemplarily, as shown in FIG. 14, an example diagram of a wireless extension header encoding format of the GTP-U protocol of the first message provided in an embodiment of this application.

In some embodiments, the wireless extension header includes first indication information. The first indication information is used to indicate that the wireless extension header includes the third information. Exemplarily, the first indication information may be identified according to the value of the PDU type as shown in FIG. 14 (x as shown in FIG. 14). For example, when the value of the PDU type is 10, it indicates that the third information is included in the wireless extension header. Among them, A in Figure 14 is a reserved bit.

It should be noted that the wireless extension header encoding format of the GTP-U protocol of the first message shown in FIG. 14 is only exemplary, and other encoding formats may also be used, which is not limited in this embodiment.

In some embodiments, the first base station 200 may use the S1202 method to send multiple first messages carrying the third information to the second base station 300. For example, the first base station 200 may use the method of S1202 to send a preset number of first messages carrying the third information to the second base station 300. For another example, the first base station 200 may use the method of S1202 to send the first message carrying the third information to the second base station 300 within a preset time.

S1203. The second base station 300 determines, according to the third information, the COUNT of the next uplink data packet that the second base station 300 expects to receive from the terminal device 100 on the second bearer, and the second base station 300 will send the message to the terminal device 100 on the second bearer. COUNT of the next downstream data packet sent.

The second bearer is a radio bearer established between the terminal device 100 and the second base station 300 after the terminal device 100 is handed over from the first base station 200 to the second base station 300.

In some embodiments, the data packet transmission method of Embodiment 2 of the present application may further include: the first base station 200 sends the first message carrying the third information to the second base station 300 through the mobility management network element. Wherein, the mobility management network element is a mobility management network element served by the terminal device 100.

In some embodiments, the first base station 200 and the second base station 300 may serve the same mobility management network element (such as MME 1). In this case, the first base station 200 may send the first message carrying the third information to the second base station 300 through the MME 1.

In other embodiments, the first base station 200 and the second base station 300 may serve different mobility management network elements. For example, as shown in FIG. 15, the first base station 200 serves the first MME 210, and the second base station 300 serves the second MME 310. In this case, as shown in S1510 in FIG. 15, the first base station 200 may sequentially send the first message carrying the third information to the second base station 300 through the first MME 210 and the second MME 310.

It should be noted that FIG. 15 uses a 4G LTE network as an example to illustrate the data packet transmission method of the embodiment of the present application. If the data packet transmission method of the embodiment of the present application is applied to other network structures, each network element shown in FIG. 15 can also be replaced by other network elements. For example, in a 5G NR network structure, the first base station 200 sends a first message carrying third information to the second base station 300 through the access management function AMF.

In the embodiment shown in FIG. 15, if the second base station 300 first receives the first message carrying the third information sent by the first base station 200 in S1510 through the mobility management network element. The second base station 300 determines, according to the third information received from the first base station 200 through the mobility management network element, the COUNT of the next uplink data packet that the second base station 300 expects to receive from the terminal device 100 on the second bearer, and the first The second base station 300 will send the COUNT of the next downlink data packet to the terminal device 100 through the second bearer.

If the second base station 300 first receives the first message carrying the third information sent by the first base station 200 through the GTP-U tunnel. The second base station 300 determines, according to the first information received from the first base station 200 through the GTP-U tunnel, the COUNT of the next uplink data packet that the second base station 300 expects to receive from the terminal device 100 on the second bearer, and the second The base station 300 will send the COUNT of the next downlink data packet to the terminal device 100 through the second bearer.

Example 3:

In this embodiment, the terminal device 100 may also determine the COUNT of the first uplink data packet lost on the first bearer according to the existing information it saves, and after the S1 handover is completed, the uplink data packet and the uplink data The COUNT of the packet is sent to the second base station 300 for the second base station 300 to set the state machine of the receiver according to the COUNT, so as to correctly receive the uplink data packet.

Compared with the prior art shown in FIG. 3, Embodiment 3 of the present application does not need to modify the existing protocols, messages, etc. At the same time, the time delay of data packet transmission status synchronization can be reduced.

As shown in FIG. 16, the data packet transmission method of the embodiment of the present application may include:

S1601. The terminal device 100 determines the COUNT of the first uplink data packet.

The first uplink data packet is the first uplink data packet lost on the first bearer. The terminal device 100 may determine the first uplink data packet lost on the first bearer according to whether it receives the confirmation message of the uplink data packet from the first base station 200.

S1602. The terminal device 100 sends the fifth information to the second base station 300 through the PDCP data packet.

Wherein, the fifth information includes the first uplink data packet lost on the first bearer and the COUNT of the uplink data packet.

It should be noted that the first uplink data packet lost on the first bearer may be sent to the second base station 300 separately from the COUNT of the uplink data packet, or may be sent to the second base station 300 together. The embodiments of this application do not limit this.

S1603. The second base station 300 parses the first uplink data packet according to the fifth information.

Wherein, the second base station 300 parses the first uplink data packet according to the fifth information, which may include:

The second base station 300 sets the state machine of the receiver to the COUNT of the first uplink data packet. Then, the second base station 300 analyzes the received first uplink data packet according to the COUNT.

It can be understood that, in order to implement the functions of any of the foregoing embodiments, the terminal device includes hardware structures and/or software modules corresponding to each function. Those skilled in the art should easily realize that in combination with the units and algorithm steps of the examples described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed by hardware or computer software-driven hardware depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered beyond the scope of this application.

The embodiment of the present application may divide the terminal device into functional modules. For example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The above-mentioned integrated modules can be implemented in the form of hardware or software functional modules. It should be noted that the division of modules in the embodiments of the present application is illustrative, and is only a logical function division, and there may be other division methods in actual implementation.

For example, in the case of dividing each functional module in an integrated manner, as shown in FIG. 17, it is a schematic structural diagram of a terminal device provided in an embodiment of this application. The terminal device 100 may include an analysis unit 1710, a sending unit 1720, and a receiving unit 1730.

Wherein, the analysis unit 1710 is used to support the terminal device to perform the above steps S601, S710, S811, S604-1, S1011, S1201, and S1601, and/or other processes used in the technology described herein. The sending unit 1720 is used to support the terminal device to execute the above steps S602, S711, S812, S605-1, S1012, and S1602 and/or other processes used in the technology described herein. The receiving unit 1730 is used to support the terminal device to perform the above steps S709a and S810, and/or other processes used in the technology described herein.

It should be noted that all relevant content of the steps involved in the foregoing method embodiments can be cited in the functional description of the corresponding functional module, and will not be repeated here.

It should be noted that the foregoing sending unit 1720 and receiving unit 1730 may include radio frequency circuits. Specifically, the terminal device can receive and send wireless signals through a radio frequency circuit. Generally, the radio frequency circuit includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and so on. In addition, the radio frequency circuit can also communicate with other devices through wireless communication. The wireless communication can use any communication standard or protocol, including but not limited to global system for mobile communications, general packet radio service, code division multiple access, broadband code division multiple access, long-term evolution, email, short message service, etc.

In an optional manner, when software is used to implement data transmission, it may be implemented in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, all or part of the processes or functions described in the embodiments of the present application are realized. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website site, computer, server or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrated with one or more available media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)).

The steps of the method or algorithm described in the embodiments of the present application may be implemented in a hardware manner, or may be implemented in a manner in which a processor executes software instructions. Software instructions can be composed of corresponding software modules, which can be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, mobile hard disk, CD-ROM or any other form of storage known in the art Medium. An exemplary storage medium is coupled to the processor, so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in the ASIC. In addition, the ASIC may be located in the detection device. Of course, the processor and the storage medium may also exist as separate components in the detection device.

Through the description of the above embodiments, those skilled in the art can clearly understand that for the convenience and brevity of the description, only the division of the above-mentioned functional modules is used as an example for illustration. In practical applications, the above-mentioned functions can be allocated as needed. It is completed by different functional modules, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above.

In the several embodiments provided in this application, it should be understood that the disclosed user equipment and method may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the modules or units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components may be It can be combined or integrated into another device, or some features can be omitted or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

The units described as separate parts may or may not be physically separate. The parts displayed as units may be one physical unit or multiple physical units, that is, they may be located in one place, or they may be distributed to multiple different places. . Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solutions of the embodiments of the present application are essentially or the part that contributes to the prior art, or all or part of the technical solutions can be embodied in the form of software products, which are stored in a storage medium There are several instructions to make a device (which may be a single-chip microcomputer, a chip, etc.) or a processor (processor) execute all or part of the steps of the methods described in the embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk and other media that can store program code .

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Any change or replacement within the technical scope disclosed in this application shall be covered by the protection scope of this application . Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A data packet transmission method, which is characterized in that it is applied to a process in which a terminal device is handed over from a first base station to a second base station. The method includes:

The terminal device determines the first count value of the first uplink data packet; the first uplink data packet is the first uplink data packet that is lost on the first bearer; wherein, the first bearer is the slave of the terminal device The radio bearer between the first base station and the first base station before the first base station is switched to the second base station, or the terminal equipment is connected to the second base station after the first base station is switched to the second base station Radio bearer between;

The terminal device sends first information to the second base station, where the first information includes the first count value.
The method according to claim 1, wherein the terminal device determining the first count value of the first uplink data packet comprises:

The terminal device receives second information from the first base station, where the second information is used to indicate third information, and the third information includes: the first sequence number of the first uplink data packet or the The second count value of the first uplink data packet;

The terminal device determines the first count value according to the second information.
The method according to claim 1 or 2, wherein the method further comprises:

The terminal device sends fourth information to the second base station, where the fourth information includes the sequence number and superframe number of the first downlink data packet lost on the first bearer.
The method according to any one of claims 1-3, wherein the sending of the first information to the second base station by the terminal device comprises:

The terminal device sends a handover confirmation message to the second base station, where the handover confirmation message carries the first information.
The method according to any one of claims 1-3, wherein the sending of the first information to the second base station by the terminal device comprises:

The terminal device sends a Packet Data Convergence Protocol PDCP data packet to the second base station, where the PDCP data packet carries the first information.
The method according to claim 5, wherein the PDCP data packet carries type indication information, and the type indication information is used to indicate that the PDCP data packet carries the first information.
A data packet transmission method, which is characterized in that it is applied to a process in which a terminal device is handed over from a first base station to a second base station. The method includes:

The second base station receives first information from the terminal equipment, where the first information includes a first count value of a first uplink data packet; the first uplink data packet is the first one lost on the first bearer Uplink data packet; wherein, the first bearer is a radio bearer between the terminal device and the first base station before handing over from the first base station to the second base station, or the terminal device is from the The radio bearer between the first base station and the second base station after handing over to the second base station;

The second base station determines, according to the first information, the sequence number and the superframe number of the next uplink data packet that the second base station expects to receive on the first bearer.
The method according to claim 7, wherein the method further comprises:

The second base station receives a second sequence number from the terminal device and a superframe number corresponding to the second sequence number, where the second sequence number is the sequence of the first downlink data packet lost by the terminal device number;

The second base station determines the sequence number and the superframe number of the next downlink data packet sent by the second base station to the terminal device according to the second sequence number and the superframe number corresponding to the second sequence number.
The method according to claim 8, wherein the method further comprises:

Receiving, by the second base station, a first message from the first base station, where the first message includes at least one second data packet buffered in the first base station;

Wherein, the second data packet includes a data packet that the first base station has sent to the terminal device, but has not received a confirmation message from the terminal device, and the first message further includes the at least one second The sequence number of the data packet;

The second base station determines the sequence number of the next downlink data packet sent by the second base station to the terminal device according to the sequence number of the at least one second data packet.
A data packet transmission method, characterized in that it is applied to a process in which a terminal device in a first system is handed over from a first base station to a second base station. The first system includes the terminal device, the first base station, and the For the second base station, the method includes:

The terminal device determines the first count value of the first uplink data packet; the first uplink data packet is the first uplink data packet that is lost on the first bearer; wherein, the first bearer is the slave of the terminal device The radio bearer between the first base station and the first base station before the first base station is switched to the second base station, or the terminal equipment is connected to the second base station after the first base station is switched to the second base station Radio bearer between;

Sending, by the terminal device, first information to the second base station, where the first information includes the first count value;

The second base station receives the first information from the terminal device;

The second base station determines the sequence number and superframe number of the next uplink data packet that the second base station expects to receive on the first bearer according to the first information.
The method according to claim 10, wherein the method further comprises:

The first base station sends second information to the terminal device, the second information is used to indicate third information, and the third information includes: the first sequence number of the first uplink data packet or the first The second count value of an uplink data packet;

The determining the first count value of the first uplink data packet by the terminal device includes:

The terminal device determines the first count value according to the second information.
The method according to claim 11, wherein the third information includes the first sequence number of the first uplink data packet, and the terminal device determines the first count value according to the second information, The method includes: the terminal device determines the first count value according to the first sequence number and a superframe number corresponding to the first sequence number; or,

The third information includes the second count value of the first uplink data packet, and the terminal device determining the first count value according to the second information includes: the terminal device determining the second count value Is the first count value.
The method according to claim 10, wherein the terminal device determining the first count value of the first uplink data packet comprises:

The terminal device uses the count value of the uplink data packet from the first base station confirmation message that the terminal device does not receive through the first bearer as the first count value;

Alternatively, the terminal device uses the count value of the next uplink data packet to be sent by the terminal device through the first bearer as the first count value.
The method according to any one of claims 10-13, wherein the method further comprises:

The terminal device sends fourth information to the second base station, where the fourth information includes a second sequence number and a superframe number corresponding to the second sequence number, and the second sequence number is that the terminal device is missing The sequence number of the first downlink data packet;

The second base station determines the sequence number and the superframe number of the next downlink data packet sent by the second base station to the terminal device according to the second sequence number and the superframe number corresponding to the second sequence number.
The method according to any one of claims 10-14, wherein the sending of the first information by the terminal device to the second base station comprises:

The terminal device sends a handover confirmation message to the second base station, where the handover confirmation message carries the first information.
The method according to any one of claims 10-14, wherein the sending of the first information by the terminal device to the second base station comprises:

The terminal device sends a Packet Data Convergence Protocol PDCP data packet to the second base station, where the PDCP data packet carries the first information.
The method according to any one of claims 14-16, wherein the method further comprises:

The first base station sends a first message to the second base station, where the first message includes at least one second data packet buffered in the first base station; the second data includes the A data packet sent to the terminal device but not receiving a confirmation message from the terminal device, the first message further including the sequence number of the at least one second data packet;

The second base station determines the sequence number of the next downlink data packet sent by the second base station to the terminal device according to the sequence number of the at least one second data packet.
A terminal device, characterized in that the terminal device includes:

The memory is used to store computer program code, where the computer program code includes instructions;

Radio frequency circuit for sending and receiving wireless signals;

The processor is configured to execute the instructions, so that the terminal device executes the data packet transmission method according to any one of claims 1-6.
A base station, characterized in that the base station includes:

The memory is used to store computer program code, where the computer program code includes instructions;

Radio frequency circuit for sending and receiving wireless signals;

The processor is configured to execute the instructions, so that the base station executes the data packet transmission method according to any one of claims 7-9.
A communication system, characterized in that, the communication system comprises: terminal equipment, a first base station and a second base station; the terminal equipment, the first base station and the second base station are used to perform the operations according to claim 10- 17. The data packet transmission method described in any one of items.
A method for data packet transmission, which is characterized in that it is applied to a process in which a terminal device is handed over from a first base station to a second base station. The method includes:

The first base station determines third information, where the third information includes the count value of the first data packet and the count value of the second data packet, and the first data packet is that the first base station expects to pass the first bearer The next uplink data packet received from the terminal device, and the second data packet is the next downlink data packet that the first base station will send to the terminal device via the first bearer, and the first bearer Is the radio bearer between the terminal device and the first base station;

The first base station sends a first message to the second base station through a user plane General Packet Radio Service Tunneling Protocol GTP-U tunnel, and the first message carries the third information.
The method according to claim 21, wherein the first base station sends the first message to the second base station through the user plane General Packet Radio Service Tunneling Protocol (GTP-U) tunnel, comprising:

Sending, by the first base station, the first message to the second base station through the GTP-U tunnel between the first base station and the second base station;

Alternatively, the first base station sends the first message to the data gateway through the GTP-U tunnel between the first base station and the data gateway, so that the data gateway communicates with the second data gateway through the data gateway. The GTP-U tunnel between the base stations sends the first message to the second base station.
The method according to claim 21 or 22, wherein the first base station sends a plurality of the first messages to the second base station through the GTP-U tunnel.
The method according to any one of claims 21-23, wherein the method further comprises:

The first base station sends the first message to the second base station through a mobility management network element, and the mobility management network element is a mobility management network element served by the terminal device.
A method for data packet transmission, which is characterized in that it is applied to a process in which a terminal device is handed over from a first base station to a second base station. The method includes:

The second base station receives a first message from the first base station through a user plane general packet radio service tunneling protocol GTP-U tunnel, the first message includes third information, and the third information includes a first data packet The count value of the second data packet, the first data packet is the next uplink data packet that the first base station expects to receive from the terminal device through the first bearer, and the second data packet is the The next downlink data packet that the first base station is about to send to the terminal device through the first bearer, where the first bearer is a radio bearer between the terminal device and the first base station;

The second base station determines, according to the third information, the count value of the next uplink data packet that the second base station expects to receive from the terminal device on the second bearer, and that the second base station is about to pass the first The second bearer is the count value of the next downlink data packet sent to the terminal equipment; the second bearer means that after the terminal equipment is handed over from the first base station to the second base station, the terminal equipment and all A radio bearer corresponding to the first bearer established between the second base stations.
The method according to claim 25, wherein the second base station receives the first message from the first base station from the user plane General Packet Radio Service Tunneling Protocol (GTP-U) tunnel, comprising:

The second base station receives the first message from the first base station through the direct GTP-U tunnel between the first base station and the second base station; or,

The second base station receives the first message through the GTP-U tunnel between the second base station and the gateway device; the first message passes through the GTP-U between the first base station and the gateway device The tunnel is transmitted from the first base station to the gateway device.
The method according to claim 25 or 26, wherein the third information is encapsulated in a wireless extension header of the GTP-U protocol of the first message.
The method according to claim 27, wherein the wireless extension header further includes first indication information, and the first indication information is used to indicate that the wireless extension header includes the third information.
The method according to claim 25 or 26, wherein the method further comprises:

The second base station receives the first message from a mobility management network element, where the mobility management network element is a mobility management network element served by the terminal device.
The method according to any one of claims 25-29, wherein the method further comprises:

After the second base station receives the first message from the first base station, the second base station discards the first message received by the second base station after the first message. news.
A terminal device, characterized in that the terminal device includes:

The memory is used to store computer program code, where the computer program code includes instructions;

Radio frequency circuit for sending and receiving wireless signals;

The processor is configured to execute the instructions, so that the terminal device executes the data packet transmission method according to any one of claims 21-24.
A base station, characterized in that the base station includes:

The memory is used to store computer program code, where the computer program code includes instructions;

Radio frequency circuit for sending and receiving wireless signals;

The processor is configured to execute the instruction, so that the base station executes the data packet transmission method according to any one of claims 25-30.
A computer-readable storage medium having computer-executable instructions stored on the computer-readable storage medium, and when the computer-executable instructions are executed by a processing circuit, the implementations of claims 1-6, 7-9, 10-17, 21- The data packet transmission method according to any one of 24 or 25-30.
A chip system, comprising: the chip system includes a processing circuit and a storage medium, and instructions are stored in the storage medium; when the instructions are executed by the processing circuit, the implementation is as claimed in claims 1-6, The data packet transmission method described in any one of 7-9, 10-17, 21-24, or 25-30.
A computer program product, the computer program product includes program instructions, when the program instructions are executed, to achieve any one of claims 1-6, 7-9, 10-17, 21-24 or 25-30 The data packet transmission method described.