WO2021223673A1

WO2021223673A1 - Data transmission method and apparatus

Info

Publication number: WO2021223673A1
Application number: PCT/CN2021/091409
Authority: WO
Inventors: 王亚鑫; 余芳; 孙海洋; 李岩
Original assignee: 华为技术有限公司
Priority date: 2020-05-06
Filing date: 2021-04-30
Publication date: 2021-11-11
Also published as: CN113630816A

Abstract

Embodiments of the present application provide a data transmission method and apparatus, capable of solving the problem of high packet loss rates during a base station handover procedure in the prior art. The method comprises: a source access network device determining a forwarding delay, wherein the forwarding delay is a time length in which the source access network device forwards a data packet to a target access network device; and the source access network device sending first information of the forwarding delay. In the embodiments of the present application, a source access network device sends information of a forwarding delay during a base station handover procedure, such that a target access network device can obtain the information of the forwarding delay. In this way, forwarding delays of forwarding paths can be taken into account during air interface scheduling, thereby improving the stability and reliability of delay-sensitive services in the base station handover procedure.

Description

Data transmission method and device

Cross-references to related applications

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on May 6, 2020, with application number 202010374725. 2. The application title is "a data transmission method and device", the entire content of which is incorporated into this application by reference .

Technical field

This application relates to the field of communication technology, and in particular to a data transmission method and device.

Background technique

The packet delay budget (PDB) is one of the quality of service (QoS) parameters. It is the data packet between the user equipment (UE) and the user plane function (UPF) The upper limit of the transmission delay, where the UPF refers to the UPF on the terminating N6 interface.

For ultra-reliable & low-latency communication (URLLC) services that have strict delay requirements, such as remote driving communication services, the end-to-end delay is less than 5 ms, and the reliability reaches 99.999%. In this scenario, if the base station can obtain the access network packet delay budget (access network PDB, AN PDB), that is, the PDB between the UE and the base station, it can reserve air interface resources in advance and optimize the scheduling of air interface resources to meet Delay requirements for URLLC services. For example, for a certain type of URLLC flow (URLLC flow), the PDB parameter value between the UE and the UPF is 5ms, the PDB between the base station and the UPF is 4ms, and the PDB between the UE and the base station is 1ms, and the base station can meet the PDB requirement of 1ms. Scheduling air interface resources can optimize the utilization of air interface resources while ensuring the latency requirements of URLLC services.

At present, the base station obtains the AN PDB through the session establishment process, so that the air interface resources are scheduled according to the AN PDB in the subsequent data transmission. However, during the base station handover process, because the UE switches the RRC connection from the source base station to the target base station, the anchor point of the core network is still at the source base station, and the target base station performs data transmission according to the AN PDB obtained by the source base station, which may cause data packets Lost.

Summary of the invention

The embodiments of the present application provide a data transmission method and device, which are used to solve the problem of high packet loss rate during base station handover in the prior art.

In a first aspect, an embodiment of the present application provides a data transmission method. The method includes: a source access network device determines a forwarding delay, where the forwarding delay is the time period for the source access network device to forward a data packet to the target access network device; The source access network device sends the first information of the forwarding delay. In the embodiment of the present application, the source access network device sends forwarding delay information during the base station handover process, so that the target access network device can obtain the forwarding delay information, so that the forwarding path can be considered when performing air interface scheduling. The forwarding delay can improve the stability and reliability of delay-sensitive services in the base station handover process.

In a possible design, the source access network device may send the first information of the forwarding delay to the source access and mobility management function.

In a possible design, the source access network device may send the first information of the forwarding delay to the target access network device.

In a possible design, before the source access network device sends the first information of the forwarding delay, the method further includes: the source access network device updates the transmission network packet delay obtained by the source access network device based on the forwarding delay Budget (TN PDB), the first information is the updated TN PDB. Through the above design, the updated TN PDB can reflect the forwarding delay, so that the target access network device can consider the forwarding delay when determining the access network packet delay budget (AN PDB) based on the updated TN PDB, thereby improving the time. The stability and reliability of delay-sensitive services in the base station handover process.

In a possible design, the forwarding delay includes the path forwarding delay of the data transmission path between the source access network device and the target access network device.

In a possible design, the forwarding delay includes the path forwarding delay of the data transmission path between the source access network device and the target access network device, and the processing time when the source access network device forwards the data packet.

In a possible design, the source access network device determines the forwarding delay, and can obtain the path forwarding delay according to the locally stored configuration information. Through the above design, if the source access network device stores the path forwarding delay locally, the source access network device can directly obtain the path forwarding delay.

In a possible design, the source access network device determines the forwarding delay, can send the first data packet to the target access network device, and record the sending time of the first data packet; the source access network device receives the target access The second data packet sent by the network access device is recorded, and the receiving time of the second data packet is recorded; the source access network device determines the path forwarding delay based on the sending time and the receiving time. In the above design, the path forwarding delay can be obtained by measuring the round-trip time of the test data packet.

In a possible design, the forwarding delay includes a forwarding delay corresponding to at least one quality of service (QoS flow).

In a second aspect, an embodiment of the present application provides a data transmission method. The method includes: a session management function receives first information of a first forwarding delay from a target access and mobility management function, and the first forwarding delay includes N services The forwarding delay corresponding to the quality QoS flow, N is an integer greater than 0; the session management function receives the QoS flow list from the target access and mobility management functions, and the QoS flow list includes N QoS flows that the target access network device accepts handover At least one QoS flow; the session management function sends second information of the second forwarding delay to the target access and mobility management function, where the second forwarding delay includes the forwarding delay corresponding to the QoS flow included in the QoS flow list.

In the embodiment of this application, the session management function can receive the forwarding delay transmitted by the source access network device through the target access and mobility management functions, and after the target access network device successfully switches the QoS flow, the QoS of the switch will be successfully switched The forwarding delay corresponding to the flow is transmitted to the target access network device through the target access and mobility management functions, so that the target access network device can obtain the forwarding delay information of each QoS flow that has been successfully handed over, so that it can perform air interface The forwarding delay of the forwarding path can be considered when scheduling, so that the stability and reliability of delay-sensitive services in the base station handover process can be improved.

In a possible design, the first information includes the updated TN PDB of N QoS flows, and the updated TN PDB of the QoS flow is obtained after the TN PDB of the QoS flow is updated based on the forwarding delay of the QoS flow ; The second information includes the updated TN PDB corresponding to the QoS flow included in the QoS flow list. Through the above design, the updated TN PDB can reflect the forwarding delay, so that the target access network device can consider the forwarding delay when determining the AN PDB based on the updated TN PDB, which can improve the delay-sensitive services in the base station handover process. Stability and reliability.

In a possible design, the first information is the first forwarding delay, and the second information is the second forwarding delay; the session management function can also send a TN PDB to the target access and mobility management function, and the TN PDB includes QoS The TN PDB of the QoS flow included in the flow list. In the above design, by sending TN PDB and forwarding delay, the target access network device can calculate AN PDB more accurately based on TN PDB, forwarding delay, and PDB.

In a third aspect, an embodiment of the present application provides a data transmission method, the method includes: a session management function determines a forwarding delay, the forwarding delay is the length of time the source access network device forwards a data packet to the target access network device; session management The function sends the first information of the forwarding delay to the target access and mobility management function. In the embodiment of this application, the session management function can sense the forwarding delay, and send forwarding delay information to the target access network device through the target access network device, so that the target access network device can obtain the forwarding delay information, so that When performing air interface scheduling, the forwarding delay of the forwarding path can be taken into consideration, so that the stability and reliability of delay-sensitive services in the base station handover process can be improved.

In a possible design, before the session management function sends the first information of the forwarding delay to the target access and mobility management function, the session management function can update the transmission network packet delay budget TN PDB based on the forwarding delay. One information is the updated TN PDB. Through the above design, the updated TN PDB can reflect the forwarding delay, so that the target access network device can consider the forwarding delay when determining the access network packet delay budget (AN PDB) based on the updated TN PDB, thereby improving the time. The stability and reliability of delay-sensitive services in the base station handover process.

In a possible design, the first information is the forwarding delay; the method further includes: the session management function sends a TN PDB to the target access and mobility management function. In the above design, by sending TN PDB and forwarding delay, the target access network device can calculate AN PDB more accurately based on TN PDB, forwarding delay, and PDB.

In a possible design, before the session management function determines the forwarding delay, the method further includes: the session management function receives the processing time from the target access and the mobility management function.

In a possible design, the session management function determines the forwarding delay, the session management function determines the first time period for the source access network device to send data packets to the source user plane function, and the source user plane function sends data to the target user plane function. The second duration of the packet and the third duration of the target user plane function sending the data packet to the target access network device; the session management function determines the path forwarding delay based on the first duration, the second duration, and the third duration. Through the above design, the session management function can obtain the forwarding delay more accurately.

In a possible design, the forwarding delay includes the forwarding delay corresponding to at least one QoS flow.

In a fourth aspect, an embodiment of the present application provides a data transmission method. The method includes: a target access network device receives first information about a forwarding delay, where the forwarding delay is the source access network device forwarding data to the target access network device The duration of the packet; the target access network device determines the access network packet delay budget based on the first information. In the embodiment of this application, the target access network device can obtain forwarding delay information, so that the forwarding delay of the forwarding path can be taken into consideration when air interface scheduling is performed, thereby improving the stability of delay-sensitive services in the base station handover process. Sex and reliability.

In a possible design, the first information is obtained after the TN PDB is updated based on the forwarding delay; or, the first information is the forwarding delay. Through the above design, the updated TN PDB can reflect the forwarding delay, so that the target access network device can consider the forwarding delay when determining the access network packet delay budget (AN PDB) based on the updated TN PDB, thereby improving the time. The stability and reliability of delay-sensitive services in the base station handover process.

In a possible design, if the first information is the forwarding delay, the method further includes: the target access network device receives the TN PDB. In the above design, by sending TN PDB and forwarding delay, the target access network device can calculate AN PDB more accurately based on TN PDB, forwarding delay, and PDB.

In a fifth aspect, an embodiment of the present application provides a data transmission method. The method includes: a first communication device receives first information about a forwarding delay from a second communication device, where the forwarding delay is the source access network device accessing the target The time period for the network device to forward the data packet; the first communication device sends the first information to the third communication device. In the embodiment of this application, the source access network device can transparently transmit the forwarding delay information through the first communication device, so that the target access network device can obtain the forwarding delay information, so that the forwarding can be considered when performing air interface scheduling. The forwarding delay of the path can improve the stability and reliability of delay-sensitive services in the base station handover process.

In a possible design, the first information is obtained after the transmission network packet delay budget TN PDB is updated based on the forwarding delay; or, the first information is the forwarding delay. Through the above design, the updated TN PDB can reflect the forwarding delay, so that the target access network device can consider the forwarding delay when determining the access network packet delay budget (AN PDB) based on the updated TN PDB, thereby improving the time. The stability and reliability of delay-sensitive services in the base station handover process.

In a possible design, the first communication device is the source access and mobility management function, the second communication device is the source access network device, and the third communication device is the target access and mobility management function.

In a possible design, the first communication device has a target access and mobility management function, the second communication device has a source access and mobility management function, and the third communication device has a session management function.

In a possible design, the first communication device is the target access and mobility management function, the second communication device is the session management function, and the third communication device is the target access network device.

In a sixth aspect, this application provides a data transmission device, which may be a communication device, or a chip or chipset in the communication device, where the communication device may be an access network device or a session management function. The device may include a processing unit and a communication unit. When the device is a communication device, the processing unit may be a processor, and the communication unit may be a transceiver; the device may also include a storage module, and the storage module may be a memory; the storage module is used to store instructions, and the processing unit The instructions stored in the storage module are executed to enable the access network device to perform the corresponding functions in the first aspect or the fourth aspect, or the processing unit executes the instructions stored in the storage module, so that the session management function executes the foregoing functions. The corresponding function in the second or third aspect. When the device is a chip or chipset in a communication device, the processing unit may be a processor, and the communication unit may be an input/output interface, a pin or a circuit, etc.; the processing unit executes the instructions stored in the storage module to Make the access network device execute the corresponding function in the first aspect or the fourth aspect, or the processing unit executes the instruction stored in the storage module, so that the session management function executes the corresponding function in the second or third aspect above . The storage module may be a storage module (for example, register, cache, etc.) in the chip or chipset, or a storage module (for example, read-only memory, random access memory, etc.) located outside the chip or chipset in the network device. Fetch memory, etc.).

In a seventh aspect, a data transmission device is provided, including a processor, a communication interface, and a memory. The communication interface is used to transmit information, and/or messages, and/or data between the device and other devices. The memory is used to store computer-executable instructions. When the device is running, the processor executes the computer-executable instructions stored in the memory, so that the device executes any design of any one of the first aspect to the fifth aspect described above The method described.

In an eighth aspect, this application also provides a computer-readable storage medium having instructions stored in the computer-readable storage medium, which when run on a computer, cause the computer to execute any one of the first to fifth aspects above Any of the aspects design the method described.

In a ninth aspect, this application also provides a computer program product including instructions, which when run on a computer, cause the computer to execute the method described in any one of the first to fifth aspects.

In a tenth aspect, this application also provides a wireless communication system, which includes a source access network device, a session management function, and a target access network device. The source access network device can perform the corresponding operations in the first aspect. The session management function can perform the corresponding function in the above-mentioned second aspect, and the target access network device can perform the corresponding function in the above-mentioned fourth aspect.

In an eleventh aspect, this application also provides a wireless communication system that includes a session management function and a target access network device, wherein the session management function can perform the corresponding function in the third aspect, the target access network The device can perform the corresponding functions in the above fourth aspect.

In a possible design, the wireless communication system may also include a source access network device.

In a twelfth aspect, the present application also provides a wireless communication system, which includes a source access network device and a target access network device, wherein the source access network device can perform the corresponding function in the above first aspect, The target access network device can perform the corresponding function in the above fourth aspect.

In a thirteenth aspect, a chip provided by an embodiment of the present application includes a memory, at least one processor, and a communication interface. The processor is coupled with the memory and is used to read a computer stored in the memory. The program executes the method described in the first aspect or any one of the first aspects of the embodiments of the present application.

In a fourteenth aspect, a chip provided by an embodiment of the present application includes a memory, at least one processor, and a communication interface. The processor is coupled with the memory and is used to read a computer stored in the memory. The program executes the method described in the second aspect or any one of the second aspects of the embodiments of the present application.

In a fifteenth aspect, a chip provided by an embodiment of the present application includes a memory, at least one processor, and a communication interface. The processor is coupled to the memory and is used to read a computer stored in the memory. The program executes the method described in the third aspect or any one of the third aspects of the embodiments of the present application.

In a sixteenth aspect, a chip provided by an embodiment of the present application includes a memory, at least one processor, and a communication interface. The processor is coupled with the memory and is used to read a computer stored in the memory. The program executes the method described in the fourth aspect or any one of the fourth aspects of the embodiments of the present application.

In a seventeenth aspect, an embodiment of the present application provides a chip including a communication interface and at least one processor, and the processor runs to execute the method described in the first aspect or any one of the first aspects of the embodiments of the present application.

In an eighteenth aspect, an embodiment of the present application provides a chip including a communication interface and at least one processor, and the processor runs to execute the method described in the second aspect or any one of the second aspects of the embodiments of the present application.

In a nineteenth aspect, an embodiment of the present application provides a chip including a communication interface and at least one processor, and the processor runs to execute the method described in the third aspect or any one of the third aspects of the embodiments of the present application.

In a twentieth aspect, an embodiment of the present application provides a chip including a communication interface and at least one processor, and the processor runs to execute the method designed in the fourth aspect or the fourth aspect of the embodiment of the present application.

It should be noted that “coupled” in the embodiments of the present application means that two components are directly or indirectly combined with each other.

Description of the drawings

FIG. 1 is a schematic diagram of the architecture of a communication system provided by an embodiment of this application;

FIG. 2 is a schematic diagram of a flow of obtaining AN PDB by a base station according to an embodiment of the application;

FIG. 3 is a schematic diagram of a PDB provided by an embodiment of the application;

FIG. 4 is a schematic diagram of another PDB provided by an embodiment of the application;

FIG. 5 is a schematic flowchart of a data transmission method provided by an embodiment of this application;

FIG. 6 is a schematic diagram of a base station handover process provided by an embodiment of the application;

FIG. 7 is a schematic diagram of transmission and forwarding delay information provided by an embodiment of this application;

FIG. 8 is a schematic diagram of a base station handover process provided by an embodiment of the application;

FIG. 9 is a schematic diagram of transmission and forwarding delay information provided by an embodiment of this application;

FIG. 10 is a schematic flowchart of a data transmission method provided by an embodiment of this application;

FIG. 11 is a schematic diagram of a base station handover process provided by an embodiment of this application;

FIG. 12 is a schematic diagram of transmission and forwarding delay information provided by an embodiment of this application;

FIG. 13 is a schematic diagram of a base station handover process provided by an embodiment of this application;

FIG. 14 is a schematic diagram of transmission and forwarding delay information provided by an embodiment of this application;

15 is a schematic flowchart of a data transmission method provided by an embodiment of this application;

FIG. 16 is a schematic diagram of a base station handover process provided by an embodiment of this application;

FIG. 17 is a schematic diagram of transmission and forwarding delay information provided by an embodiment of this application;

FIG. 18 is a schematic diagram of a base station handover process provided by an embodiment of this application;

FIG. 19 is a schematic diagram of transmission and forwarding delay information provided by an embodiment of this application;

FIG. 20 is a schematic structural diagram of a data transmission device provided by an embodiment of this application;

FIG. 21 is a schematic structural diagram of a data transmission device provided by an embodiment of this application.

Detailed ways

In order to facilitate the understanding of the embodiments of the present application, the following introduces terms related to the embodiments of the present application:

PDB: The upper limit of the transmission delay of the data packet between the UE and the UPF on the terminating N6 interface. PDB is one of the QoS parameters. PDB includes the transmission network packet delay budget (transport network PDB, TN PDB) and AN PDB, where TN PDB refers to the upper limit of the transmission delay between the base station and the UPF on the terminating N6 interface, and AN PDB refers to the transmission between the UE and the base station The upper limit of the delay.

In order to describe the technical solutions of the embodiments of the present application more clearly, the data transmission method and device provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

A possible communication system architecture to which the data transmission method provided in the embodiments of this application is applicable. The communication system architecture may include network open function network elements, policy control function network elements, data management network elements, and application function network elements. , Core network access and mobility management function network element, session management function network element, terminal equipment, access network equipment, user plane function network element and data network. 1 shows a possible example of the architecture of the communication system, which specifically includes: network exposure function (NEF) network element, policy control function (PCF), data management ( unified data management (UDM) network element, application function (AF) network element, access and mobility management function (AMF), session management function (SMF) network element, User equipment (UE), access network (AN) equipment, user plane function (UPF) network elements, and data network (DN). Among them, the AMF network element and the terminal device can be connected through the N1 interface, the AMF and the AN device can be connected through the N2 interface, the AN device and the UPF can be connected through the N3 interface, and the SMF and UPF can be connected through the N4 interface. , UPF and DN can be connected through the N6 interface. The interface name is only an example, and the embodiment of the present application does not specifically limit this. It should be understood that the embodiment of the present application is not limited to the communication system shown in FIG. 1, and the name of the network element shown in FIG. The limit of the network element. The function of each network element or device in the communication system is described in detail below:

The terminal equipment, which may also be referred to as user equipment (UE), mobile station (MS), mobile terminal (MT), etc., is a way to provide users with voice and/or data connectivity Sexual equipment. For example, the terminal device may include a handheld device with a wireless connection function, a vehicle-mounted device, and the like. At present, the terminal devices may be: mobile phones (mobile phones), tablet computers, notebook computers, handheld computers, mobile Internet devices (MID), wearable devices, virtual reality (VR) devices, augmented Augmented reality (AR) equipment, wireless terminals in industrial control (industrial control), wireless terminals in self-driving (self-driving), wireless terminals in remote medical surgery, and smart grid (smart grid) Wireless terminals in ), wireless terminals in transportation safety, wireless terminals in smart cities, or wireless terminals in smart homes, etc. Wherein, the terminal device described in FIG. 1 is shown as a UE, which is only used as an example and does not limit the terminal device.

The wireless access network may be the AN shown in FIG. 1, which provides wireless access services to the terminal equipment. The access network device is a device that connects the terminal device to a wireless network in the communication system. The access network device is a node in a radio access network, which may also be called a base station, or may also be called a radio access network (RAN) node (or device). At present, some examples of access network equipment are: new generation node B (generated node B, gNB), transmission reception point (TRP), evolved node B (evolved Node B, eNB), radio network controller (radio network controller, RNC), node B (Node B, NB), base station controller (BSC), base transceiver station (base transceiver station, BTS), home base station (for example, home evolved NodeB, or home Node B, HNB, baseband unit (BBU), or wireless fidelity (Wifi) access point (AP), etc.

The data network, such as the DN shown in Figure 1, may be the Internet, IP Multi-media Service (IMS) network, regional network (ie, local network, such as mobile edge computing, MEC) network) and so on. The data network includes an application server, and the application server provides business services for the terminal device by performing data transmission with the terminal device.

The core network is used to connect the terminal device to a DN that can implement the service of the terminal device. The following describes the functions of each network element in the core network:

The access and mobility management function network element can be used to manage the access control and mobility of the terminal device. In practical applications, it includes the mobile in the network framework of long term evolution (LTE). The mobility management function in the management entity (mobility management entity, MME), and the access management function is added, which can be specifically responsible for the terminal equipment registration, mobility management, tracking area update process, reachability detection, and session management Selection of functional network elements, mobile state transition management, etc. For example, in 5G, the access and mobility management function network element may be referred to as an AMF network element. For example, as shown in FIG. 1, in future communications, such as 6G, the access and mobility management function network element is still It can be called an AMF network element or has other names, which is not limited in this application.

The session management function network element can be used to be responsible for the session management of the terminal device (including the establishment, modification and release of the session), the selection and reselection of the user plane function network element, and the internet protocol of the terminal device. , IP) address allocation, quality of service (quality of service, QoS) control, etc. For example, in 5G, the session management function network element may be called an SMF network element. For example, as shown in FIG. 1, in future communications, such as 6G, the session management function network element may still be called an SMF network element, or There are other names, and this application is not limited.

The policy control function network element can be used to be responsible for policy control decision-making, to provide functions such as service data flow and application detection, gating control, QoS and flow-based charging control, etc. For example, in 5G, the policy control function network element may be called a PCF network element. For example, as shown in FIG. 1, in future communications, such as 6G, the policy control function network element may still be a PCF network element, or Other names are not limited in this application.

The main function of the application function network element is to interact with the 3rd generation partnership project (3GPP) core network to provide services to influence service flow routing, access network capability opening, policy control, etc. For example, in 5G, the application function network element may be called an AF network element. For example, as shown in Figure 1, in future communications, such as 6G, the application function network element may still be an AF network element, or there may be other name.

The data management network element may be used to manage subscription data of the terminal device, registration information related to the terminal device, and the like. For example, in 5G, the data management network element may be called a unified data management network element (unified data management, UDM). For example, as shown in FIG. 1, in future communications, such as 6G, the data management network element may still be It is called a UDM network element, or has other names, and is not limited in this application.

The network open function network element can be used to enable 3GPP to safely provide network service capabilities to third-party AF (for example, Service Capability Server (SCS), Application Server (AS), etc.). For example, in 5G, the network open function network element may be called NEF, for example, as shown in Figure 1, in future communications, such as 6G, the network open function network element may still be called NEF network element, or there may be other The name of this application is not limited.

The above network elements in the core network can also be called functional entities. They can be network elements implemented on dedicated hardware, software instances running on dedicated hardware, or instances of virtualized functions on an appropriate platform. For example, the aforementioned virtualization platform may be a cloud platform.

It should be noted that the architecture of the communication system shown in FIG. 1 is not limited to only include the network elements shown in the figure, and may also include other devices not shown in the figure. The specifics of this application will not be listed here. .

It should be noted that the embodiment of the present application does not limit the distribution form of each network element in the core network. The distribution form shown in FIG. 1 is only exemplary, and the present application does not limit it.

For the convenience of description, the following description of this application will take the network element shown in FIG. 1 as an example, and the XX network element will be directly referred to as XX, for example, the SMF network element will be referred to as SMF. It should be understood that the names of all network elements in this application are merely examples, and may also be referred to as other names in future communications, or the network elements involved in this application may also be used by other entities or devices with the same function in future communications. Instead, this application does not limit this. Here is a unified explanation, and I won’t repeat it in the follow-up.

It should be noted that the communication system shown in FIG. 1 does not constitute a limitation of the communication system to which the embodiments of the present application can be applied. The communication system architecture shown in FIG. 1 is a 5G system architecture. Optionally, the method of the embodiment of the present application is also applicable to various future communication systems, such as 6G or other communication networks.

For URLLC services with strict delay requirements, such as communication services for remote driving, the end-to-end delay is less than 5 ms, and the reliability is 99.999%. In this scenario, if the base station can obtain AN PDB, it can reserve air interface resources in advance and optimize the scheduling of air interface resources to meet the delay requirements of URLLC services. For example, for a certain type of URLLC flow, the PDB parameter value between the UE and the UPF is 5ms, and the TN PDB between the base station and the UPF is 4ms, so the AN PDB between the UE and the base station is 1ms, so the base station can be based on the 1ms AN PDB Demand scheduling of air interface resources can optimize the utilization of air interface resources while ensuring the latency requirements of URLLC services.

At present, the base station obtains the AN PDB through the session establishment process, so that the air interface resources are scheduled according to the AN PDB in the subsequent data transmission. For example, as shown in Figure 2, the process for the base station to obtain the AN PDB may include:

S201: The UE sends a PDU session establishment request to the AMF.

In S202, AMF selects SMF, and SMF selects PCF and UPF.

S203: The PCF sends a policy and charging control (PCC) policy to the SMF, where the PCC policy includes a 5G QoS identifier (5G QoS identifier, 5QI).

The SMF can determine the PDB between the UE and the UPF according to the 5G QoS corresponding to the 5QI.

S204: The SMF sends a session establishment request to the UPF.

Among them, if the SMF does not store the TN PDB between the base station and the UPF, the session establishment/modification request may carry indication information, and the indication information is used to request the UPF to feed back the TN PDB.

S205: The UPF sends a session establishment response to the SMF.

Wherein, if the session establishment/modification request carries indication information requesting the UPF to feed back TN PDB, the session establishment/modification response may carry TN PDB or TN path information.

It can be understood that the TN PDB information between the UPF and each base station is pre-configured.

S206: The SMF sends PDB related information to the AMF.

For example, PDB related information is AN PDB calculated by SMF based on TN PDB and 5QI. For another example, PDB related information is TN PDB and 5QI determined by SMF based on TN path information.

S207: The AMF sends the PDB related information to the base station.

S208: The base station determines the AN PDB according to the PDB related information, and performs scheduling control according to the QoS flow corresponding to the AN PDB.

S209: The base station and the UE interact to complete the air interface configuration, and the RAN, AMF, and SMF interact to complete the update of the PDU session management context, and complete the session establishment process.

From the above, it can be seen that the base station obtains the AN PDB during the establishment of the PDU session, so as to schedule the air interface resources according to the AN PDB in the subsequent data transmission. However, in the base station handover process, because the UE switches the RRC connection from the source base station to the target base station, and the anchor point of the core network is still at the source base station, the downlink data transmission process during the base station handover process is: the core network equipment transfers to the source base station. The base station sends the data, and then the source base station forwards the data to the target base station, and the target base station sends the data to the UE. Similarly, the uplink data transmission process is: the UE sends data to the target base station, the target base station forwards the data to the source base station, and the source base station sends the data to the core network device. Due to the existence of the transmission process between the source base station and the target base station during the base station handover, the PDB between the target base station and the UE is lower than the AN PDB obtained by the source base station. The target base station schedules the air interface according to the AN PDB obtained by the source base station. Data transfer by resources may cause packet loss.

For example, the PDB between the UE and the UPF is 10ms, and the TN PDB between the UPF and the source base station is 5ms. Therefore, the AN PDB obtained by the source base station is 5ms. The transmission process takes 2ms, so the PDB between the target base station and the UE is 3ms. However, according to the current data transmission method, the target base station will perform data transmission according to the 5ms AN PDB scheduling air interface resources, which may cause data packet loss.

Based on this, the present application provides a data transmission method and device to solve the problem of high packet loss rate during base station handover in the prior art. Among them, the method and the device are based on the same inventive concept. Since the principles of the method and the device to solve the problem are similar, the implementation of the device and the method can be referred to each other, and the repetition will not be repeated.

It should be understood that in the embodiments of the present application, "at least one" refers to one or more, and "multiple" refers to two or more than two. "And/or" describes the association relationship of the associated object, indicating that there can be three relationships, for example, A and/or B, which can mean: A alone exists, A and B exist at the same time, and B exists alone, where A, B can be singular or plural. The character "/" generally indicates that the associated objects before and after are in an "or" relationship. "The following at least one (item)" or similar expressions refers to any combination of these items, including any combination of single item (item) or plural items (item). For example, at least one of a, b, or c can mean: a, b, c, a and b, a and c, b and c, or a, b and c, where a, b, c It can be single or multiple.

In addition, it should be understood that in the description of this application, words such as "first" and "second" are only used for the purpose of distinguishing description, and cannot be understood as indicating or implying relative importance, nor can it be understood as indicating Or imply the order, nor the number.

The data transmission method provided in the embodiments of the present application can be applied to a base station handover scenario, where when the UE moves from one base station to another base station, the base station needs to be handed over.

In an implementation scenario, there may be an Xn user plane forwarding tunnel between the source access network device (source RAN, S-RAN) and the target access network device (target RAN, T-RAN), namely S-RAN and T-RAN. There is an Xn-U interface between RANs, so that S-RAN and T-RAN can forward tunneled data through the user plane. For example, in the downlink transmission process, the transmission delay between S-RAN and T-RAN is the delay caused by the process of S-RAN forwarding data packets to T-RAN, as shown in Figure 3. It is understandable that the Xn user plane forwarding tunnel may be established between S-RAN and T-RAN, or the Xn user plane forwarding tunnel may also be a tunnel for forwarding through other base stations. For example, an Xn user plane tunnel is established between S-RAN and base station 1, and an Xn user plane tunnel is established between base station 1 and T-RAN. Therefore, data can be transmitted between S-RAN and T-RAN through base station 1. What needs to be explained Yes, only one base station in base station 1 is used as an example for description here, and the number of base stations through which data is transmitted between S-RAN and T-RAN is not specifically limited.

In another implementation scenario, there may be no Xn user plane forwarding tunnel between S-RAN and T-RAN, that is, S-RAN and T-RAN can configure source UPF (source UPF, S-UPF) and S-UPF through SMF. Target UPF (target UPF, T-UPF) transmits data, that is, S-UPF and T-UPF are used as forwarding network elements. For example, in downlink transmission, the process of S-RAN forwarding data packets to T-RAN is, S-RAN Forward the data packet to S-UPF, S-UPF forwards the data packet to T-UPF, and T-UPF forwards the data packet to T-RAN. The transmission delay between S-RAN and T-RAN is S -RAN->S-UPF->T-UPF->T-RAN The delay caused by the transmission of data packets is shown in Figure 4. In uplink transmission, the process of T-RAN forwarding data packets to S-RAN is: T-RAN forwards data packets to T-UPF, T-UPF forwards the data packets to S-UPF, and S-UPF then forwards the data The packet is forwarded to S-RAN, and the transmission delay between T-RAN and S-RAN is the delay generated by T-RAN->T-UPF->S-UPF->S-RAN transmission of data packets. Among them, S-UPF and T-UPF may be the same network element or different network elements. If S-UPF and T-UPF are the same network element, the data forwarding process of S-UPF and T-UPF may not be executed.

The data transmission method provided in the present application will be described in detail below in conjunction with the accompanying drawings.

Embodiment 1: The method can be applied to the scenario shown in FIG. 3. In the first embodiment, an Xn user plane forwarding tunnel is established between S-RAN and T-RAN, but no Xn control plane forwarding tunnel is established, that is, there is an Xn-U interface between S-RAN and T-RAN, but there is no Xn -C interface. As shown in Figure 5, the method may include:

S501: The S-RAN determines a first forwarding delay, where the first forwarding delay is the duration for the S-RAN to forward a data packet to the T-RAN.

Exemplarily, the first forwarding delay may include the path forwarding delay of the data transmission path between the S-RAN and the T-RAN. Among them, the data transmission path between S-RAN and T-RAN may be an Xn user plane forwarding tunnel established between S-RAN and T-RAN, or a data transmission path forwarded through other base stations.

Alternatively, the first forwarding delay may also include the path forwarding delay of the data transmission path between the S-RAN and the T-RAN, and the processing time when the S-RAN forwards the data packet. Among them, the processing time when the S-RAN forwards a data packet may be a packet data convergence protocol (packet data convergence protocol, PDCP) layer processing delay.

In an implementation manner, the path forwarding delay can be determined in the following manner: the S-RAN can obtain the path forwarding delay according to the locally stored configuration information.

In another implementation manner, the path forwarding delay can also be determined in the following manner: S-RAN sends the first data packet to T-RAN and records the sending time of the first data packet; S-RAN receives the data sent by T-RAN The second data packet, and the receiving time of the second data packet is recorded; the S-RAN determines the path forwarding delay based on the sending time and the receiving time, for example, the path forwarding delay can be equal to 0.5×(receiving time-sending time).

In an exemplary illustration, the forwarding delay may be QoS Flow granular. For example, in step S501, the S-RAN may determine the forwarding delays corresponding to the N QoS Flows, and the first forwarding delay may include N QoS Flows. Respectively corresponding forwarding delay, N is an integer greater than 0.

S502: The S-RAN sends the first information of the first forwarding delay to the S-AMF. Correspondingly, the S-AMF receives the first information of the first forwarding delay from the S-RAN.

In an implementation manner, the first information may be obtained after the TN PDB is updated based on the first forwarding delay. In an implementation manner, before the S-RAN sends the first information of the first forwarding delay, the TN PDB obtained by the S-RAN may be updated based on the first forwarding delay to obtain the updated TN PDB, and the updated TN PDB That is the first information. For example, assuming that the first forwarding delay is 2 ms and TN PDB is 5 ms, the updated TN PDB may be equal to the sum of the first forwarding delay and TN PDB, that is, 7 ms.

Further, if the forwarding delay is of the granularity of the QoS Flow, the S-RAN can update the TN PDB of the QoS Flow according to the forwarding delay corresponding to the QoS Flow to obtain the updated TN PDB of the QoS Flow. Therefore, the first information may include the updated TN PDB of N QoS Flows, and the updated TN PDB of the QoS Flow is obtained after the TN PDB of the QoS Flow is updated based on the forwarding delay of the QoS Flow.

In another implementation manner, the first information may be the first forwarding delay.

S503: The S-AMF sends the first information of the first forwarding delay to the T-AMF. Correspondingly, the T-AMF receives the first information of the first forwarding delay from the S-AMF.

S504: The T-AMF sends the first information of the first forwarding delay to the SMF. Correspondingly, the SMF receives the first information of the first forwarding delay from the T-AMF.

S505: The T-AMF sends a QoS Flow list to the SMF, where the QoS Flow list includes configuration information of at least one QoS Flow for which the T-RAN accepts handover. Correspondingly, SMF receives the QoS Flow list from T-AMF.

In an implementation manner, before step S505, the SMF may trigger the T-RAN to verify the session. For example, SMF can instruct T-RAN to verify at least one session through T-AMF. After verifying the at least one session, T-RAN determines to receive the handover session, and feeds back to T-AMF the QoS Flow corresponding to the handover session. Profile information.

S506: The SMF sends second information of the second forwarding delay to the T-AMF, where the second forwarding delay includes the forwarding delay corresponding to the QoS Flow included in the QoS Flow list.

In an implementation manner, if the first information includes the updated TN PDB of N QoS Flows, the second information may include the updated TN PDB corresponding to the QoS Flow included in the QoS Flow list.

In another implementation manner, if the first information is the first forwarding delay, the second information may be the second forwarding delay. In an exemplary illustration, the first forwarding delay may include the forwarding delays respectively corresponding to the N QoS Flows, and the second information may include the forwarding delays respectively corresponding to the QoS Flows included in the QoS Flow list. The second forwarding delay may be a subset of the first forwarding delay. In another exemplary description, the forwarding delays of the N QoS Flows may be the same, so the first forwarding delay may be a forwarding delay value, and the second forwarding delay and the first forwarding delay may be the same.

In this implementation manner, the SMF may also send a TN PDB to the T-AMF, and the TN PDB includes the TN PDB of the QoS flow included in the QoS Flow list.

S507: The T-AMF sends the second information to the T-RAN.

S508: The T-RAN determines the AN PDB based on the second information.

In an exemplary description, taking QoS Flow 1 as an example, if the second information includes the updated TN PDB of QoS Flow 1, the AN PDB of QoS Flow 1 can be equal to the PDB of QoS Flow 1 minus the updated QoS Flow 1 The difference of TN PDB.

In another exemplary description, taking QoS Flow 1 as an example, if the second information includes the forwarding delay corresponding to QoS Flow 1, the AN PDB of QoS Flow 1 can be equal to the PDB of QoS Flow 1 minus the PDB of QoS Flow 1. TN PDB, minus the difference of forwarding delay corresponding to QoS Flow 1.

It should be noted that T-AMF and S-AMF may be the same network element or different network elements. If T-AMF and S-AMF are the same network element, in the above S501-S507 process, the actions of S-AMF and T-AMF can be performed by the same network element, and between S-AMF and T-AMF The interaction process may not be executed.

In the embodiment of this application, the S-RAN sends forwarding delay information to the T-RAN during the base station handover process, so that the T-RAN can consider the forwarding delay of the forwarding path when scheduling the air interface, thereby improving the delay sensitivity. The stability and reliability of the service in the base station handover process.

In order to better understand the solutions provided by the embodiments of the present application, the following takes T-AMF and S-AMF as different network elements as an example, and the base station handover procedure will be described in conjunction with specific examples.

Example 1:

As shown in Figure 6, the base station handover procedure may include:

S601: The S-RAN determines the forwarding delay.

Exemplarily, the S-RAN can determine that there is an Xn user plane transmission path with the T-RAN by querying local information, that is, there is an Xn-U connection. S-RAN can obtain the path forwarding delay of the data transmission path between S-RAN and T-RAN according to the pre-configured information, or obtain the data transmission path between S-RAN and T-RAN in the form of sending measurement data packets. Path forwarding delay. For the specific process, please refer to the related description of S501, which will not be repeated here.

S602. The S-RAN updates the value of TN-PDB according to the forwarding delay.

For example, if the forwarding delay is 6ms and the TN-PDB is 4ms, the S-RAN can combine the forwarding delay with TN-PDB and the updated TN-PDB, that is, the updated TN-PDB is 10ms.

S603: The S-RAN sends a handover request message to the S-AMF, where the handover request message may carry the updated TN PDB.

Exemplarily, the handover request message may be a Handover Required message. It should be understood that this is only an example. In other access standards or in the future communication development, the updated TN PDB may also be carried in other messages. Make specific restrictions.

S604: If the T-RAN is not within the service range of the S-AMF, the S-AMF selects the T-AMF serving the T-RAN according to the identification information of the T-RAN.

S605: The S-AMF sends a UE context creation request message to the T-AMF, where the UE context creation request message may carry the updated TN PDB.

Exemplarily, the create UE context request message may be the Namf_Communication_CreateUEContext Request message. It should be understood that this is only an example. In other access standards or in the future development of communication, the updated TN PDB may also be carried in other messages. There is no specific limitation here.

S606: The T-AMF sends a session management (session management, SM) context update request message to the SMF, where the SM context update request message may carry the updated TN PDB.

Exemplarily, the update SM context request message may be the Namf_PDUSession_UpdateSMContext Request message. It should be understood that this is only an example for illustration. In other access standards, or in the future communication development, the updated TN PDB may also be carried in other messages. There is no specific limitation here.

S607: The SMF controls the establishment of an uplink tunnel between a PDU session anchor (PSA) and the T-UPF.

S608: The SMF feeds back the path establishment status to the T-AMF, where the path establishment status may include the session that the T-UPF allows to accept the handover and QoS Flow information.

S609: The T-AMF sends a handover request to the T-RAN, which includes a list of sessions and QoS Flows that the T-UPF allows to accept handover.

Wherein, step S610 may be executed when T-AMF receives Response messages of all PDU Sessions, or when the maximum waiting time is reached, or step S610 may be executed after T-AMF receives Response messages of all PDU Sessions, or reaches the maximum waiting time Execute after time.

S610: The T-RAN sends a handover request confirmation message to the T-AMF, where the handover request confirmation message may carry the session and QoS Flow information for which the T-RAN accepts the handover.

Exemplarily, the handover request confirmation message may be a Handover Request Acknowledge message. It should be understood that this is only an example for illustration. In other access standards, or in the future development of communication, other messages may also be used to carry T-RAN acceptance of handover. Session and QoS Flow information are not specifically limited here.

S611: The T-AMF sends an update SM context response message to the SMF, where the update SM context response message may carry the session and QoS Flow information for which the T-RAN accepts the handover.

Exemplarily, the update SM context response message may be the Nsmf_PDUSession_UpdateSMContext Response message. It should be understood that this is only an example. In other access standards, or in the future development of communication, other messages may also be used to carry the T-RAN accepting handover. Session and QoS Flow information are not specifically limited here.

S612: The SMF sends the updated TN PDB corresponding to the QoS Flow for which the T-RAN accepts the handover to the T-AMF.

Exemplarily, the SMF may also send the 5QI corresponding to the QoS Flow for which the T-RAN accepts the handover to the T-AMF.

S613: The T-AMF sends a handover command to the T-RAN, where the handover command carries the updated TN PDB corresponding to the QoS Flow for which the T-RAN accepts the handover. The handover command may also carry the 5QI corresponding to the QoS Flow for which the T-RAN accepts the handover.

Exemplarily, the handover command may be a Handover Command message. It should be understood that this is only an example. In other access standards, or in the future development of communication, other messages can also be used to carry the QoS Flow corresponding to the T-RAN accepting handover. The updated TN PDB is not specifically limited here.

S614: The T-RAN calculates and updates the AN PDB according to the updated TN PDB corresponding to the QoS Flow and the PDB information in the 5QI of each QoS Flow.

For example, the updated TN PDB corresponding to the QoS Flow is 12 ms, the PDB in the 5QI of the QoS Flow is 20 ms, and the AN PDB of the QoS Flow is 8 ms.

S615: The T-RAN sends a handover command to the UE, where the handover command is used to instruct the UE to switch to the T-RAN.

S616: The UE executes a base station handover procedure.

Example 1 For the scenario where there is an Xn user plane transmission tunnel between RANs, S-RAN can obtain the forwarding delay between T-RAN and update TN-PDB, and pass S-RAN->S-AMF->T -AMF->SMF->T-AMF->T-RAN is forwarded to T-RAN, as shown in Figure 7, so that T-RAN can consider forwarding delay factors when determining AN PDB, which can improve the time The stability and reliability of delay-sensitive services in the base station handover process.

Example 2:

As shown in Figure 8, the base station handover procedure may include:

For details of S801, refer to S601, which will not be repeated here.

S802 to S805 are similar to the above S603 to S606, except that S603 to S606 carry the updated TN PDB while S802 to S805 carry the forwarding delay.

For S806 to S810, please refer to the above S607 to S611 for details, which will not be repeated here.

S811~S812, similar to the above S612~S613, the difference is that S612~S613 carry the updated TN PDB corresponding to the QoS Flow that the T-RAN accepts handover, while S811～S812 carry the QoS Flow that the T-RAN accepts handover The corresponding forwarding delay.

S813~S815, please refer to S614~S616 for details, which will not be repeated here.

Example 2 For the scenario where there is an Xn user plane transmission tunnel between RANs, S-RAN can obtain the forwarding delay between T-RAN and pass S-RAN->S-AMF->T-AMF->SMF- The path of >T-AMF->T-RAN is forwarded to T-RAN, as shown in Figure 9, so that T-RAN can consider the factor of forwarding delay when determining the AN PDB, which can improve the handover of delay-sensitive services at the base station Stability and reliability in the process.

Embodiment 2: This method can be applied to the scenario shown in Figure 4. In the scenario shown in Figure 4, no Xn user plane forwarding tunnel and Xn control plane forwarding tunnel are established between S-RAN and T-RAN, namely There is no Xn-U and Xn-C interface between S-RAN and T-RAN. As shown in Figure 10, the method may include:

S1001: The SMF determines a first forwarding delay, where the first forwarding delay is the duration for the S-RAN to forward a data packet to the T-RAN.

Exemplarily, the first forwarding delay may include the path forwarding delay of the data transmission path between the S-RAN and the T-RAN. Among them, the data transmission path between S-RAN and T-RAN may be a path forwarded by core network equipment. For example, the data transmission path between S-RAN and T-RAN may be S-RAN->S-UPF-> T-UPF->T-RAN.

In an implementation manner, the processing duration may be received from T-AMF. For example, the S-RAN can determine the processing duration and send it to the SMF through T-AMF.

Exemplarily, the path forwarding delay can be determined in the following manner: SMF determines the first time length for S-RAN to send data packets to S-UPF, the second time length for S-UPF to send data packets to T-UPF, and T-UPF The third duration for sending the data packet to the T-RAN; SMF determines the path forwarding delay based on the first duration, the second duration, and the third duration. For example, the path forwarding delay may be equal to the sum of the first duration, the second duration, and the third duration.

In an exemplary illustration, the forwarding delay may be at the granularity of the QoS Flow. For example, in step S1001, the SMF may determine the forwarding delay corresponding to each of the N QoS Flows, and N is an integer greater than zero.

S1002: The SMF sends the first information of the first forwarding delay to the T-AMF. Correspondingly, T-AMF can receive the first information from SMF.

In an implementation manner, the first information may be obtained after the TN PDB is updated based on the first forwarding delay. In this implementation manner, before the SMF sends the first information, the TN PDB may be updated based on the first forwarding delay to obtain the updated TN PDB, and the updated TN PDB is the first information. For example, assuming that the first forwarding delay is 2 ms and TN PDB is 5 ms, the updated TN PDB may be equal to the sum of the first forwarding delay and TN PDB, that is, 7 ms.

Further, if the forwarding delay is of the granularity of the QoS Flow, the SMF can update the TN PDB of the QoS Flow according to the forwarding delay corresponding to the QoS Flow to obtain the updated TN PDB of the QoS Flow. Therefore, the first information may include the updated TN PDB of N QoS Flows, and the updated TN PDB of the QoS Flow is obtained after the TN PDB of the QoS Flow is updated based on the forwarding delay of the QoS Flow.

In an implementation manner, SMF can also send TN PDB to T-AMF.

S1003. The T-AMF sends the first information to the T-RAN. Correspondingly, the T-RAN receives the first information from the T-AMF.

In an implementation manner, if the first information is the first forwarding delay, the T-AMF may also send a TN PDB to the T-RAN.

S1004: The T-RAN determines the AN PDB based on the first information.

For details of S1004, please refer to the relevant description of S508, which will not be repeated here.

Example three:

As shown in Figure 11, the base station handover procedure may include:

S1101 to S1104 are similar to S603 to S606, except that S603 to S606 carry the updated TN PDB, while S1101 to S1109 do not carry the updated TN PDB. Optionally, the processing time can be carried in steps S1101 to S1104.

Optionally, before step S1101, the S-RAN may find that there is no Xn connection with the T-RAN by querying local information, and the handover control plane message needs to be forwarded through the N2 interface. At the same time, the forwarding of user plane data also needs to be configured through the N2 interface. S-RAN decides to trigger N2 handover.

S1105~S1109, please refer to S607~S611 for details, which will not be repeated here.

S1110: The SMF establishes a forwarding tunnel between the S-UPF and the T-UPF.

S1111, SMF is based on the QoS Flow information that the T-RAN accepts handover, the path forwarding delay, and the TN PDB of each QoS Flow. Optionally, it can also determine the updated TN corresponding to the QoS Flow that the T-RAN accepts handover according to the processing time. PDB.

S1112~S1116, please refer to the above S612~S616 for details, and will not be repeated here.

Example 3: S-RAN sends the processing time to SMF through S-AMF and T-AMF. After S-UPF and T-UPF forwarding tunnels are configured, SMF calculates and updates according to the path forwarding delay and processing time and TN PDB TN PDB is sent to T-RAN through T-AMF, as shown in Figure 12, so that T-RAN can consider forwarding delay factors when determining AN PDB, which can improve the stability of delay-sensitive services in the base station handover process Sex and reliability.

Example four:

As shown in Figure 13, the base station handover procedure may include:

For S1301 to S1310, please refer to the above S1101 to S1110 for details, which will not be repeated here.

S1311: The SMF determines the forwarding delay corresponding to the QoS Flow that the T-RAN accepts the handover according to the QoS Flow information and the path forwarding delay.

S1312~S1316, similar to S1113~S1116, the difference is that S1113~S1116 carry the updated TN PDB corresponding to the QoS Flow that T-RAN accepts handover, while S1312～S1316 carry the QoS Flow corresponding to T-RAN accepts handover The forwarding delay.

Example 4: S-RAN sends processing time to SMF through S-AMF and T-AMF. After SMF is configured with S-UPF and T-UPF forwarding tunnels, it calculates forwarding delay and processing time based on path forwarding delay and processing time. After T-AMF is sent to T-RAN, as shown in Figure 14, T-RAN can consider the factor of forwarding delay when determining AN PDB, which can improve the stability and reliability of delay-sensitive services in the base station handover process. sex.

Embodiment 3: This method can be applied to the scenario shown in Figure 3. In the scenario shown in Figure 3, an Xn control plane forwarding tunnel is established between S-RAN and T-RAN, namely S-RAN and T-RAN There is an Xn-C interface between. As shown in Figure 15, the method may include:

S1501. The S-RAN determines a first forwarding delay, where the first forwarding delay is the duration for the S-RAN to forward a data packet to the T-RAN.

For S1501, please refer to the relevant description of S501 above for details, and details are not repeated here.

S1502: The S-RAN sends the first information of the first forwarding delay to the T-RAN. Correspondingly, the T-RAN receives the first information of the first forwarding delay from the S-RAN.

Among them, the manner in which the S-RAN sends the first information to the T-RAN in S1502 is the same as the manner in which the S-RAN sends the first information to the S-AMF in S502. For details, please refer to the relevant description of the above S502, which will not be repeated here. .

In one implementation manner, if the first information is the first forwarding delay, the S-RAN may also send a TN PDB to the T-RAN.

S1503. The T-RAN determines the AN PDB based on the first information.

The manner in which the T-RAN determines the AN PDB according to the first information in S1503 is the same as the manner in which the T-RAN determines the AN PDB according to the second information in S508. For details, please refer to the relevant description of the foregoing S508, which will not be repeated here.

In order to better understand the solutions provided in the embodiments of the present application, the base station handover procedure will be described below in conjunction with specific examples.

Example five:

As shown in Figure 16, the base station handover procedure may include:

S1601: The AMF sends mobility control information to the S-RAN. Among them, the mobility control information is used to indicate information such as roaming information and access restrictions of the UE.

S1602: The UE reports measurement information to the S-RAN. For example, the measurement information may include reference signal received power (RSRP), reference signal received quality (RSRQ), and so on.

S1603: The S-RAN decides to switch the UE to the T-RAN by means of Xn handover according to the measurement information reported by the UE and the local strategy.

S1604 to S1605, please refer to the above S601 and S602 for details, which will not be repeated here.

S1606: The S-RAN sends a handover request message to the T-RAN, and the handover request message may carry the updated TN PDB. In addition, the handover request message may also carry 5QI.

S1607: The T-RAN calculates the AN PDB in the handover process according to the updated TN PDB and the PDB corresponding to the 5QI.

S1608: The T-RAN determines and controls whether handover is allowed.

S1609: The T-RAN sends a handover request confirmation message to the S-RAN, where the handover request confirmation message is used to indicate to accept the handover of the UE. The handover request confirmation message may include a handover command (Handover Command), which is used to instruct the UE to access the T-RAN through a random access procedure.

Exemplarily, the handover request confirmation message may be a Handover Request Acknowledge message. It should be understood that this is only an example. In other access standards, or in the future development of communication, other messages can also be used to instruct to accept the handover of the UE. Here There is no specific limitation.

S1610, the base station handover procedure.

Example 5 For the scenario where there is an Xn user plane transmission tunnel between RANs, S-RAN can obtain the forwarding delay between T-RAN and update TN-PDB, and pass the Xn between S-RAN and T-RAN The control plane transmission tunnel is forwarded to T-RAN, as shown in Figure 17, so that T-RAN can consider the factor of forwarding delay when determining AN PDB, which can improve the stability and reliability of delay-sensitive services in the base station handover process. sex.

Example 6:

As shown in Figure 18, the base station handover procedure may include:

S1801 to S1804, please refer to S1601 to S1604 for details, which will not be repeated here.

S1805: The S-RAN sends a handover request message to the T-RAN. The handover request message may carry forwarding delay and TN PDB. In addition, the handover request message may also carry 5QI.

In S1806, the T-RAN calculates the AN PDB in the handover process according to the forwarding delay, TN PDB, and PDB corresponding to 5QI.

S1807~S1809, please refer to S1608~S1610 for details, which will not be repeated here.

Example 6 For the scenario where there is an Xn user plane transmission tunnel between RANs, S-RAN can obtain the forwarding delay between T-RAN and forward it to the Xn control plane transmission tunnel between S-RAN and T-RAN. T-RAN, as shown in Figure 19, so that T-RAN can consider the factor of forwarding delay when determining the AN PDB, which can improve the stability and reliability of delay-sensitive services in the base station handover process.

Based on the same technical concept as the method embodiment, the embodiment of the present application provides a data transmission device. The structure of the device may be as shown in FIG. 20, including a processing unit 2001 and a communication unit 2002.

In an implementation manner, the data transmission device may be specifically used to implement the method executed by the source access network device (S-RAN) in the embodiments of FIG. 5 to FIG. 9 and FIG. 15 to FIG. 19. The device may be a source access network. The device may also be a chip or a chip set or a part of the chip used to perform related method functions in the source access network device. Wherein, the processing unit 2001 is configured to determine a forwarding delay, and the forwarding delay is the time length for the source access network device to forward the data packet to the target access network device. The communication unit 2002 is configured to send the first information of the forwarding delay.

Optionally, the processing unit 2001 may be further configured to: before the communication unit 2002 sends the first information of the forwarding delay, update the transmission network packet delay budget TN PDB obtained by the source access network device based on the forwarding delay, first The information is the updated TN PDB.

Exemplarily, the forwarding delay may include the path forwarding delay of the data transmission path between the source access network device and the target access network device.

Alternatively, the forwarding delay may include the path forwarding delay of the data transmission path between the source access network device and the target access network device, and the processing time when the source access network device forwards the data packet.

In some embodiments, the processing unit 2001, when determining the forwarding delay, may be specifically configured to obtain the path forwarding delay according to locally stored configuration information.

In other embodiments, the processing unit 2001, when determining the delay in forwarding, may be specifically configured to: send the first data packet to the target access network device through the communication unit 2002, and record the sending time of the first data packet; The unit 2002 receives the second data packet sent by the target access network device, and records the receiving time of the second data packet; and determines the path forwarding delay based on the sending time and the receiving time.

Exemplarily, the forwarding delay includes the forwarding delay corresponding to at least one quality of service QoS flow.

In one implementation, the data transmission device may be specifically used to implement the session management function (AMF) execution method in the embodiments of FIGS. 5-9. The device may be an AMF, or a chip or chipset or chip in the AMF. Part of the function used to perform related methods. Among them, the communication unit 2002 is used to communicate with target access and mobility management functions. The processing unit 2001 is configured to execute through the communication unit 2002: receiving first information about the first forwarding delay from the target access and mobility management function, where the first forwarding delay includes forwarding delays corresponding to N quality of service QoS flows, N is an integer greater than 0; the QoS flow list is received from the target access and mobility management function, and the QoS flow list includes at least one QoS flow for which the target access network device accepts handover among the N QoS flows; access to the target and mobility The management function sends the second information of the second forwarding delay, where the second forwarding delay includes the forwarding delay corresponding to the QoS flow included in the QoS flow list.

Exemplarily, the first information may include the updated TN PDB of N QoS flows, and the updated TN PDB of the QoS flow is obtained after the TN PDB of the QoS flow is updated based on the forwarding delay of the QoS flow. The second information may include the updated TN PDB corresponding to the QoS flow included in the QoS flow list.

Alternatively, the first information may be the first forwarding delay, and the second information may be the second forwarding delay;

Optionally, the processing unit 2001 may be further configured to send a TN PDB to the target access and mobility management function through the communication unit 2002, where the TN PDB includes the TN PDB of the QoS flow included in the QoS flow list.

Alternatively, the forwarding delay may also include the path forwarding delay of the data transmission path between the source access network device and the target access network device, and the processing time when the source access network device forwards the data packet.

In one implementation, the data transmission device can be specifically used to implement the session management function (AMF) execution method in the embodiments shown in FIG. 10 to FIG. 14. The device may be AMF, or a chip or chipset in AMF. Or a part of the chip used to perform related method functions. Wherein, the processing unit 2001 is configured to determine a forwarding delay, and the forwarding delay is the time length for the source access network device to forward the data packet to the target access network device. The communication unit 2002 is configured to send the first information of the forwarding delay to the target access and mobility management function.

Optionally, the processing unit 2001 may be further configured to: before the communication unit 2002 sends the first information of the forwarding delay to the target access and mobility management function, update the transmission network packet delay budget TN PDB based on the forwarding delay, The first information is the updated TN PDB.

Exemplarily, the first information may be the forwarding delay. The communication unit 2002 may also be used to send a TN PDB to the target access and mobility management functions.

Optionally, the communication unit 2002 may be further configured to: before the processing unit 2001 determines the forwarding delay, receive the processing time length from the target access and mobility management function.

In some embodiments, the processing unit 2001, when determining the delay in forwarding, may be specifically configured to: determine the first time period for the source access network device to send a data packet to the source user plane function, and the source user plane function to send the data packet to the target user plane function. The second duration of the data packet and the third duration of the target user plane function sending the data packet to the target access network device; the path forwarding delay is determined based on the first duration, the second duration, and the third duration.

In an implementation manner, the data transmission device can be specifically used to implement the method executed by the source access network device (S-RAN) in the embodiments shown in FIG. 5 to FIG. 19. The device may be a source access network device or It is the chip or chip set or part of the chip used to perform related method functions in the source access network device. The communication unit 2002 is configured to receive the first information of the forwarding delay, and the forwarding delay is the time length for the source access network device to forward the data packet to the target access network device; the processing unit 2001 is configured to determine the connection based on the first information Network packet delay budget.

Exemplarily, the first information may be obtained after the TN PDB is updated based on the forwarding delay; or, the first information may be the forwarding delay.

Optionally, if the first information is the forwarding delay, the communication unit 2002 may also be used to: receive TN PDB.

The division of modules in the embodiments of this application is illustrative, and it is only a logical function division. In actual implementation, there may be other division methods. In addition, the functional modules in the various embodiments of this application can be integrated into one process. In the device, it can also exist alone physically, or two or more modules can be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware or software functional modules. It can be understood that the function or implementation of each module in the embodiment of the present application may further refer to the related description of the method embodiment.

In one possible manner, the data transmission device may be as shown in FIG. 21. The device may be a communication device or a chip in a communication device. The communication device may be an access network device or a session management function. The device may include a processor 2101, a communication interface 2102, and a memory 2103. The processing unit 2001 may be a processor 2101. The communication unit 2002 may be a communication interface 2102.

The processor 2101 may be a central processing unit (central processing unit, CPU), or a digital processing unit, and so on. The communication interface 2102 may be a transceiver, an interface circuit such as a transceiver circuit, etc., or a transceiver chip, and so on. The device also includes a memory 2103, which is used to store a program executed by the processor 2101. The memory 2103 may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), etc., and may also be a volatile memory, such as random access memory (random access memory). -access memory, RAM). The memory 2103 is any other medium that can be used to carry or store desired program codes in the form of instructions or data structures and that can be accessed by a computer, but is not limited to this.

The processor 2101 is configured to execute the program code stored in the memory 2103, and is specifically configured to execute the actions of the aforementioned processing unit 2001, which will not be repeated in this application. The communication interface 2102 is specifically configured to perform the actions of the above-mentioned communication unit 2002, which will not be repeated in this application.

The specific connection medium between the foregoing communication interface 2102, the processor 2101, and the memory 2103 is not limited in the embodiment of the present application. In the embodiment of the present application, in FIG. 21, the memory 2103, the processor 2101, and the communication interface 2102 are connected by a bus 2104. The bus is represented by a thick line in FIG. 21. The connection mode between other components is only for schematic illustration. , Is not limited. The bus can be divided into an address bus, a data bus, a control bus, and so on. For ease of representation, only one thick line is used in FIG. 21 to represent it, but it does not mean that there is only one bus or one type of bus.

The embodiment of the present invention also provides a computer-readable storage medium for storing computer software instructions required to execute the above-mentioned processor, which contains a program required to execute the above-mentioned processor.

Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, this application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, this application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

This application is described with reference to flowcharts and/or block diagrams of methods, equipment (systems), and computer program products according to this application. It should be understood that each process and/or block in the flowchart and/or block diagram, and the combination of processes and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing equipment to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing equipment are used to generate It is a device that realizes the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing equipment to work in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction device. The device implements the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

These computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operation steps are executed on the computer or other programmable equipment to produce computer-implemented processing, so as to execute on the computer or other programmable equipment. The instructions provide steps for implementing the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

Obviously, those skilled in the art can make various changes and modifications to the application without departing from the spirit and scope of the application. In this way, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, then this application is also intended to include these modifications and variations.

Claims

A data transmission method, characterized in that the method includes:

The source access network device determines a forwarding delay, where the forwarding delay is the time length for the source access network device to forward the data packet to the target access network device;

The source access network device sends the first information of the forwarding delay.
The method according to claim 1, wherein before the source access network device sends the first information of the forwarding delay, the method further comprises:

The source access network device updates the transmission network packet delay budget TN PDB acquired by the source access network device based on the forwarding delay, and the first information is the updated TN PDB.
The method according to claim 1 or 2, wherein the forwarding delay includes a path forwarding delay of a data transmission path between the source access network device and the target access network device;

Alternatively, the forwarding delay includes the path forwarding delay of the data transmission path between the source access network device and the target access network device, and the processing time when the source access network device forwards the data packet.
The method according to claim 3, wherein the source access network device determining the forwarding delay comprises:

The source access network device obtains the path forwarding delay according to locally stored configuration information.
The method according to claim 3, wherein the source access network device determining the forwarding delay comprises:

Sending, by the source access network device, a first data packet to the target access network device, and recording the sending time of the first data packet;

Receiving, by the source access network device, a second data packet sent by the target access network device, and recording the receiving time of the second data packet;

The source access network device determines the path forwarding delay based on the sending time and the receiving time.
The method according to any one of claims 1 to 5, wherein the forwarding delay comprises a forwarding delay corresponding to at least one quality of service QoS flow.
A data transmission method, characterized in that the method includes:

The session management function receives first information about the first forwarding delay from the target access and mobility management function, where the first forwarding delay includes forwarding delays corresponding to N quality of service QoS flows, where N is greater than 0 Integer

The session management function receives a QoS flow list from the target access and mobility management function, where the QoS flow list includes at least one QoS flow to which the target access network device accepts handover among the N QoS flows;

The session management function sends second information of a second forwarding delay to the target access and mobility management function, where the second forwarding delay includes the forwarding delay corresponding to the QoS flow included in the QoS flow list .
The method according to claim 7, wherein the first information includes the updated TN PDB of the N QoS flows, and the updated TN PDB of the QoS flow is the TN PDB of the QoS flow. PDB is obtained after updating based on the forwarding delay of the QoS flow;

The second information includes the updated TN PDB corresponding to the QoS flow included in the QoS flow list.
8. The method of claim 7, wherein the first information is the first forwarding delay, and the second information is the second forwarding delay;

The method also includes:

The session management function sends a TN PDB to the target access and mobility management function, where the TN PDB includes the TN PDB of the QoS flow included in the QoS flow list.
The method according to any one of claims 7 to 9, wherein the forwarding delay comprises a path forwarding delay of a data transmission path between a source access network device and a target access network device;

Alternatively, the forwarding delay includes the path forwarding delay of the data transmission path between the source access network device and the target access network device, and the processing time when the source access network device forwards the data packet.
A data transmission method, characterized in that the method includes:

The session management function determines the forwarding delay, where the forwarding delay is the time length for the source access network device to forward the data packet to the target access network device;

The session management function sends the first information of the forwarding delay to the target access and mobility management function.
The method according to claim 11, wherein before the session management function sends the first information of the forwarding delay to the target access and mobility management function, the method further comprises:

The session management function updates the transmission network packet delay budget TN PDB based on the forwarding delay, and the first information is the updated TN PDB.
The method of claim 11, wherein the first information is the forwarding delay;

The method also includes:

The session management function sends a TN PDB to the target access and mobility management function.
The method according to any one of claims 11-13, wherein the forwarding delay comprises a path forwarding delay of a data transmission path between the source access network device and the target access network device .
The method according to any one of claims 11-13, wherein the forwarding delay comprises a path forwarding delay of a data transmission path between the source access network device and the target access network device , And the processing time when the source access network device forwards the data packet.
The method according to claim 15, characterized in that, before the session management function determines the forwarding delay, the method further comprises:

The session management function receives the processing duration from the target access and mobility management function.
The method according to any one of claims 14-16, wherein the session management function determining the forwarding delay comprises:

The session management function determines the first time length for the source access network device to send the data packet to the source user plane function, the second time length for the source user plane function to send the data packet to the target user plane function, and the target user The third time duration for the face function to send a data packet to the target access network device;

The session management function determines the path forwarding delay based on the first duration, the second duration, and the third duration.
The method according to any one of claims 11-17, wherein the forwarding delay comprises a forwarding delay corresponding to at least one quality of service QoS flow.
A data transmission method, characterized in that the method includes:

The target access network device receives the first information of the forwarding delay, where the forwarding delay is the time length for the source access network device to forward the data packet to the target access network device;

The target access network device determines an access network packet delay budget based on the first information.
The method according to claim 19, wherein the first information is obtained after the TN PDB is updated based on the forwarding delay;

Alternatively, the first information is the forwarding delay.
The method according to claim 20, wherein if the first information is the forwarding delay, the method further comprises:

The target access network device receives the TN PDB.
The method according to any one of claims 19-21, wherein the forwarding delay comprises a forwarding delay corresponding to at least one quality of service QoS flow.
A data transmission device is characterized in that it comprises:

Communication interface, used to communicate with other devices;

Memory, used to store computer programs and data;

The processor is configured to run the computer program in the memory, read the computer program in the memory, and execute the method according to any one of claims 1-6 through the communication interface.
A data transmission device is characterized in that it comprises:

Communication interface, used to communicate with other devices;

Memory, used to store computer programs and data;

The processor is configured to run the computer program in the memory, read the computer program in the memory, and execute the method according to any one of claims 7-10 through the communication interface.
A data transmission device is characterized in that it comprises:

Communication interface, used to communicate with other devices;

Memory, used to store computer programs and data;

The processor is configured to run the computer program in the memory, read the computer program in the memory, and execute the method according to any one of claims 11-18 through the communication interface.
A data transmission device is characterized in that it comprises:

Communication interface, used to communicate with other devices;

Memory, used to store computer programs and data;

The processor is configured to run the computer program in the memory, read the computer program in the memory, and execute the method according to any one of claims 19-22 through the communication interface.
A computer storage medium, characterized in that a computer program is stored in the computer storage medium, and when the computer program is executed by a computer, the computer is caused to execute the method according to any one of claims 1-22.