Data transmission method and device

Abstract

The invention provides a data transmission method and device. The method is applied to a source base station in a terminal equipment switching process. The method comprises the following steps: sending a first switching request, wherein the first switching request comprises a quality of service (QoS) parameter of a protocol data unit (PDU) set of terminal equipment; and receiving first indication information, wherein the first indication information is used for indicating the processing capability of the target base station for the PDU set in the switching process of the terminal equipment. And executing a switching operation according to the first indication information. Therefore, during inter-station switching, resource waste caused by capacity mismatching between the base stations during cache data forwarding can be avoided, so that the forwarding efficiency is improved.

Description

Technical Field

[0001] The present application relates to the field of communications, and more specifically, to a data transmission method and device. Background Art

[0002] With the continuous development of communication technology, extended reality (XR) is one of the 5G multimedia applications that is currently being considered in the industrial field.

[0003] The 5G system forwards and processes data based on the granularity of the quality of service flow (QoS flow) and guarantees its quality of service (QoS). The 5G core network (5GC) in the 5G system indicates the QoS requirements of different QoS flows to the radio access network (RAN) through the QoS profile. For ordinary services in the 5G system, QoS guarantees are only required at the granularity of protocol data units (PDUs), but for XR services, QoS guarantees are usually expected to be required at the granularity of PDU sets. For XR services, the base station is usually required to have the ability to process PDU sets, so the base station will report its own processing capabilities for PDU sets to the core network.

[0004] When inter-station handover occurs in a terminal device, how to avoid resource waste caused by the mismatch between the capabilities of the source base station and the target base station during the handover process has become an urgent problem to be solved. Summary of the invention

[0005] The present application provides a data transmission method and device, which can avoid the waste of resources caused by the mismatch of capabilities between base stations when forwarding cache data during inter-station switching, thereby improving forwarding efficiency.

[0006] In a first aspect, a data transmission method is provided, which is applied to a source base station in a terminal device switching process. The method comprises: sending a first switching request, the first switching request comprising a quality of service (QoS) parameter of a protocol data unit (PDU) set of the terminal device. Receiving first indication information, the first indication information being used to indicate a processing capability of a target base station for a PDU set in the terminal device switching process. According to the first indication information, performing a switching operation.

[0007] In the above technical solution, the source base station fully considers the processing capability of the target base station for the PDU set and makes a reasonable switching decision, thereby avoiding the waste of link resources and even data decoding errors caused by the mismatch in the processing capability of the two base stations for the PDU set.

[0008] In combination with the first aspect, in some implementations of the first aspect, the QoS parameters include one or more of a protocol data unit set delay budget PSDB, a protocol data unit set error rate PSER, and a protocol data unit set integrity information PSIHI.

[0009] In combination with the first aspect, in certain implementations of the first aspect, performing a switching operation based on the first indication information includes: when the first indication information indicates that the target base station has the processing capability of the PDU set, sending a first cache data packet, the first cache data packet including relevant information of the PDU set.

[0010] In the above technical solution, when the first indication information indicates that the target base station has the PDU set processing capability, the source base station directly forwards the cached data to be forwarded to the target base station. Compared with the source base station directly forwarding the cached data to the target base station when the capability of the target base station is unknown, the solution of the present application can ensure that there is no waste of link resources when forwarding the cached data.

[0011] In combination with the first aspect, in certain implementations of the first aspect, performing a switching operation based on the first indication information includes: when the first indication information indicates that the target base station does not have the processing capability of the PDU set, sending a second cached data packet, the second cached data packet does not include relevant information of the PDU set; or, determining a new target base station; or, sending a second switching request to the target base station, the second switching request does not include QoS parameters of the PDU set.

[0012] In the above technical solution, when the first indication information indicates that the target base station does not have the PDU set processing capability, the source base station can reduce the packet header size of the forwarded data while ensuring that the inter-station switching process between the source base station and the target base station remains unchanged by removing the relevant information of the PDU set in the data packet of the cached data to be forwarded, thereby reducing the consumption of forwarding link resources. Alternatively, when the first indication information indicates that the target base station does not have the PDU set processing capability, by finding a more suitable new target base station, the capabilities of the two base stations for inter-station switching can be matched, ensuring the QoS guarantee based on the PDU set, which is more suitable for the data transmission process based on the PDU set. Alternatively, when the first indication information indicates that the target base station does not have the PDU set processing capability, the inter-station switching between the source base station and the target base station can continue to be implemented, thereby avoiding problems such as service interruption caused by the terminal's inability to switch in time. At the same time, the packet header size of the forwarded data is also reduced, thereby reducing the consumption of forwarding link resources.

[0013] In a second aspect, a data transmission method is provided, the method being applied to a source base station where a terminal device is located, the method comprising: sending a first capability query message, the first capability query message being used to query the processing capability of at least one candidate base station for a protocol data unit PDU set, and at least one candidate base station will be used for a terminal device switching process. Receiving second indication information, the second indication information being used to indicate the processing capability of at least one candidate base station for the PDU set. Performing a switching operation according to the second indication information.

[0014] In combination with the second aspect, in certain implementations of the second aspect, performing a switching operation according to the second indication information includes: determining a candidate base station having the processing capability of a PDU set indicated by the second indication information as a target base station in the terminal device switching process.

[0015] In the above technical solution, by understanding the processing capability of at least one candidate base station for PDU set, the candidate base station with PDU set processing capability is used as the target base station during the inter-station switching process, thereby ensuring the QoS requirements of the terminal device based on PDU set.

[0016] In combination with the second aspect, in certain implementations of the second aspect, performing a switching operation according to the second indication information includes: when one of at least one candidate base stations is determined as a target base station in a terminal device switching process, if the target base station does not have the processing capability of the PDU set, sending third cache data, and the third cache data does not include relevant information of the PDU set.

[0017] In the above technical solution, even if there is no base station with processing capability for PDU set among the candidate base stations around the source base station, a suitable inter-station switching strategy can be determined in advance, thereby improving the efficiency of data forwarding and avoiding resource waste.

[0018] In a third aspect, a data transmission method is provided, the method being applied to a source base station in a terminal device switching process, the method comprising: sending a fourth switching request, the fourth switching request comprising a quality of service QoS parameter of a PDU set. Receiving a second feedback message. According to the second feedback message, determining that a target base station in the terminal device switching process is an old version base station, and the old version base station does not have a processing capability for a protocol data unit PDU set. Performing a second operation.

[0019] It should be understood that the old version base station may be the old base station described below.

[0020] In the above technical solution, by not including indication information of the target base station's processing capability for the PDU set in the second feedback message, it can be determined that the target base station is an old base station, that is, an old version base station, so that during the inter-station switching process, a data transmission strategy that is more suitable for the old base station is determined to improve data forwarding efficiency and avoid waste of resources.

[0021] In combination with the third aspect, in certain implementations of the third aspect, the QoS parameters include one or more of a protocol data unit set delay budget PSDB, a protocol data unit set error rate PSER, and a protocol data unit set integrity information PSIHI.

[0022] In combination with the third aspect, in certain implementations of the third aspect, performing the second operation includes: sending a fourth cached data packet, the fourth cached data packet does not include relevant information of the PDU set; or, determining a new target base station; or, sending a fifth switching request to the target base station, the fifth switching request does not include QoS parameters of the PDU set.

[0023] In the above technical solution, when the target base station is an old base station that has not been upgraded, that is, an old version base station, the inter-station switching between the source base station and the old base station can continue to be implemented, thereby saving and avoiding problems such as service interruption caused by the terminal not being able to switch in time. At the same time, the packet header size of the forwarded data is also reduced, thereby reducing the consumption of forwarding link resources.

[0024] In a fourth aspect, a data transmission method is provided, the method being applied to a first base station, the method comprising: determining third indication information, the third indication information being used to indicate capability information of the first base station for a low latency, low loss and scalable throughput L4S mechanism. When a trigger condition is met, the third indication information is sent to a core network.

[0025] In the above technical solution, the first base station can promptly notify the core network of its support for L4S, so that the core network can understand the capabilities of the first base station, and thus select an appropriate method when there is a need for L4S, which helps to adjust the service transmission rate in a timely manner and improve user experience. For example, if the first base station only supports ECN marking but not congestion reporting, the core network can instruct the first base station to perform ECN marking. If the first base station only supports congestion reporting but not ECN marking, the core network can instruct the first base station to perform congestion reporting and the core network will be responsible for ECN marking, thereby ensuring that L4S is carried out normally.

[0026] In combination with the fourth aspect, in some implementations of the fourth aspect, the third indication information is used to indicate whether the first base station has both the explicit congestion notification ECN marking capability and the congestion information reporting capability.

[0027] In combination with the fourth aspect, in certain implementations of the fourth aspect, the third indication information is used to indicate whether the first base station has ECN marking capability and congestion information reporting capability respectively.

[0028] In combination with the fourth aspect, in certain implementations of the fourth aspect, the third indication information is used to indicate whether the first base station has an ECN marking capability or a congestion information reporting capability.

[0029] In combination with the fourth aspect, in some implementations of the fourth aspect, before determining the third indication information, the method further includes: receiving a first capability reporting request, the first capability reporting request being used to request capability information of the first base station for the L4S mechanism. When the trigger condition is met, sending the third indication information includes: sending the third indication information in response to the first capability reporting request.

[0030] In the above technical solution, triggering the third indication information through the capability reporting request allows the core network to obtain the capability of the base station for the L4S mechanism in a timely manner when it is needed, thereby helping to determine a more reasonable data transmission strategy.

[0031] In conjunction with the fourth aspect, in some implementations of the fourth aspect, before determining the third indication information, the method further includes: receiving a first start message, the first start message being used to instruct the first base station to mark the ECN and / or start a congestion information reporting operation. When a trigger condition is met, sending the third indication information includes: sending the third indication information when the first base station has or does not have an ECN marking capability and / or a congestion information reporting capability.

[0032] In the above technical solution, by triggering the base station to report the third indication information to the core network through a startup message, the core network can obtain the capability of the first base station through less information interaction when determining that the first base station needs to have the capability for the L4S mechanism.

[0033] In conjunction with the fourth aspect, in some implementations of the fourth aspect, before determining the third indication information, the method further includes: receiving first data, the first data including a quality of service QoS flow for the L4S mechanism. When the trigger condition is met, sending the third indication information includes: after receiving the first data, sending the third indication information.

[0034] In the above technical solution, by including the QoS flow for the L4S mechanism in the data, the base station is triggered to actively report the third indication information, so that the core network can obtain the capability of the first base station through less information interaction.

[0035] In conjunction with the fourth aspect, in some implementations of the fourth aspect, before determining the third indication information, the method further includes: receiving a second start message, the second start message being used to instruct the first base station to mark the ECN and / or start a congestion information reporting operation. When the trigger condition is met, sending the third indication information includes: sending the third indication information in response to the second start message.

[0036] In some implementations, the second startup information instructs the first base station to mark an ECN for an uplink data flow or a downlink data flow of a first QoS flow or a first DRB in the terminal device and / or to start a congestion information reporting operation.

[0037] It should be understood that the first QoS flow is any QoS flow in the terminal device, and the first DRB is any DRB in the terminal device.

[0038] In some implementations, the second startup information is used to indicate that the second base station has marked or is marking ECN and / or performing congestion information reporting operations for the uplink data flow or downlink data flow of the second QoS flow or the second DRB in the terminal device.

[0039] It should be understood that the second QoS flow is any QoS flow in the terminal device, and the second DRB is any DRB in the terminal device.

[0040] In some implementations, the second startup information is carried in a third switching request, and the third switching request is used to request the terminal device to switch from the second base station to the first base station.

[0041] In the above technical solution, when switching between stations, triggering the first base station to report the capability for the L4S mechanism helps to ensure that when switching from the second base station to the first base station, the data transmission of the terminal device can continue to be transmitted in the manner of the L4S mechanism.

[0042] In some implementations, the second startup information is carried in a first response message, the first response message is in response to a terminal device context query request message sent by the first base station to the second base station, and the first response message is used to indicate the context of the terminal device to the first base station. It should be understood that before receiving the first response message, the first base station sends a terminal device context query request message to the second base station, and the context query request message is used to query the context of the terminal device.

[0043] In combination with the fourth aspect, in certain implementations of the fourth aspect, the method further includes: within a first time period, no third indication information is sent, and the starting moment of the first time period is when the third indication information is sent each time.

[0044] In the above technical scheme, by limiting the sending frequency of the third indication information by presetting the duration, the two extreme sending methods of frequently sending the third indication information and sending the third indication information once can be avoided, thereby reducing the frequency of capability reporting and ensuring the timeliness and accuracy of capability reporting.

[0045] In a fifth aspect, a data transmission device is provided, the device comprising a transceiver unit and a processing unit: the transceiver unit is used to send a first switching request, the first switching request includes a quality of service QoS parameter of a protocol data unit PDU set of a terminal device. The transceiver unit is used to receive first indication information, the first indication information is used to indicate the processing capability of the target base station for the PDU set during the switching process of the terminal device. The processing unit is used to perform a switching operation according to the first indication information.

[0046] It should be understood that the beneficial effects corresponding to the scheme of the fifth aspect are similar to those of the first aspect and will not be elaborated here.

[0047] In combination with the fifth aspect, in certain implementations of the fifth aspect, the QoS parameters include one or more of a protocol data unit set delay budget PSDB, a protocol data unit set error rate PSER, and a protocol data unit set integrity information PSIHI.

[0048] In combination with the fifth aspect, in certain implementations of the fifth aspect, the processing unit is specifically used to: when the first indication information indicates that the target base station has the processing capability of the PDU set, control the transceiver unit to send a first cache data packet, and the first data cache packet includes relevant information of the PDU set.

[0049] In combination with the fifth aspect, in certain implementations of the fifth aspect, the processing unit is specifically used to: when the first indication information indicates that the target base station does not have the processing capability of the PDU set, control the transceiver unit to send a second cached data packet, the second cached data packet does not include relevant information of the PDU set; or, determine a new target base station; or, control the transceiver unit to send a second switching request to the target base station, the second switching request does not include the QoS parameters of the PDU set.

[0050] In a sixth aspect, a data transmission device is provided, the device comprising a transceiver unit and a processing unit: the transceiver unit is used to send a first capability query message, the first capability query message is used to query the processing capability of at least one candidate base station for a protocol data unit PDU set, and at least one candidate base station will be used for a terminal device switching process. The transceiver unit is used to receive second indication information, the second indication information is used to indicate the processing capability of at least one candidate base station for a PDU set. The processing unit is used to perform a switching operation according to the second indication information.

[0051] It should be understood that the beneficial effects corresponding to the scheme of the sixth aspect are similar to those of the second aspect and will not be elaborated here.

[0052] In combination with the sixth aspect, in certain implementations of the sixth aspect, the processing unit is specifically used to: determine the candidate base station with the processing capability of the PDU set indicated by the second indication information as the target base station in the terminal device switching process.

[0053] In combination with the sixth aspect, in certain implementations of the sixth aspect, the processing unit is specifically used to include: when one of at least one candidate base stations is determined as the target base station in the terminal device switching process, if the target base station does not have the processing capability of the PDU set, controlling the transceiver unit to send third cache data, and the third cache data does not include relevant information of the PDU set.

[0054] In a seventh aspect, a data transmission device is provided, the device including a transceiver unit and a processing unit including: the transceiver unit is used to send a fourth switching request, the fourth switching request includes a quality of service QoS parameter of a PDU set. The transceiver unit is used to receive a second feedback message. The processing unit is used to determine, based on the second feedback message, that the target base station in the terminal device switching process is an old base station, and the old base station does not have the processing capability for the protocol data unit PDU set. The processing unit is used to perform a second operation.

[0055] It should be understood that the beneficial effects corresponding to the scheme of the seventh aspect are similar to those of the third aspect and will not be elaborated here.

[0056] In combination with the seventh aspect, in certain implementations of the seventh aspect, the QoS parameters include one or more of a protocol data unit set delay budget PSDB, a protocol data unit set error rate PSER, and a protocol data unit set integrity information PSIHI.

[0057] In combination with the seventh aspect, in certain implementations of the seventh aspect, the processing unit is specifically used to: control the transceiver unit to send a fourth cached data packet, the fourth cached data packet does not include relevant information of the PDU set; or, determine a new target base station; or, control the transceiver unit to send a fifth switching request to the target base station, the fifth switching request does not include the QoS parameters of the PDU set.

[0058] In an eighth aspect, a data transmission device is provided, the device comprising a processing unit and a transceiver unit: the processing unit is used to determine third indication information, the third indication information is used to indicate capability information of the first base station for a low latency, low loss and scalable throughput L4S mechanism. The transceiver unit is used to send the third indication information to the core network when a trigger condition is met.

[0059] It should be understood that the beneficial effects corresponding to the scheme of the eighth aspect are similar to those of the fourth aspect and will not be elaborated here.

[0060] In combination with the eighth aspect, in certain implementations of the eighth aspect, the third indication information is used to indicate whether the first base station has both the explicit congestion notification ECN marking capability and the congestion information reporting capability.

[0061] In combination with the eighth aspect, in certain implementations of the eighth aspect, the third indication information is used to indicate whether the first base station has ECN marking capability and congestion information reporting capability respectively.

[0062] In combination with the eighth aspect, in certain implementations of the eighth aspect, the third indication information is used to indicate whether the first base station has an ECN marking capability or a congestion information reporting capability.

[0063] In conjunction with the eighth aspect, in certain implementations of the eighth aspect, before the processing unit is used to determine the third indication information, the transceiver unit is further used to: receive a first capability reporting request, the first capability reporting request being used to request capability information of the first base station for the L4S mechanism. The transceiver unit is specifically used to: send the third indication information in response to the first capability reporting request.

[0064] In conjunction with the eighth aspect, in some implementations of the eighth aspect, before the processing unit is used to determine the third indication information, the transceiver unit is further used to: receive a first startup message, the first startup message is used to instruct the first base station to mark the ECN and / or start a congestion information reporting operation. The transceiver unit is specifically used to: send the third indication information when the first base station has or does not have the ECN marking capability and / or the congestion information reporting capability.

[0065] In conjunction with the eighth aspect, in certain implementations of the eighth aspect, before the processing unit is used to determine the third indication information, the transceiver unit is further used to: receive first data, where the first data includes a quality of service QoS flow for the L4S mechanism. The processing unit is specifically used to: after receiving the first data, control the transceiver unit to send the third indication information.

[0066] In conjunction with the eighth aspect, in some implementations of the eighth aspect, before the processing unit is used to determine the third indication information, the transceiver unit is further used to: receive a second startup message, where the second startup message is used to instruct the first base station to mark the ECN and / or start a congestion information reporting operation. The transceiver unit is specifically used to: send the third indication information in response to the second startup message.

[0067] In some implementations, the second startup information instructs the first base station to mark an ECN for an uplink data flow or a downlink data flow of a first QoS flow or a first DRB in the terminal device and / or to start a congestion information reporting operation.

[0068] It should be understood that the first QoS flow is any QoS flow in the terminal device, and the first DRB is any DRB in the terminal device.

[0069] In some implementations, the second startup information is used to indicate that the second base station has marked or is marking ECN and / or performing congestion information reporting operations for the uplink data flow or downlink data flow of the second QoS flow or the second DRB in the terminal device.

[0070] It should be understood that the second QoS flow is any QoS flow in the terminal device, and the second DRB is any DRB in the terminal device.

[0071] In some implementations, the second startup information is carried in a third switching request, and the third switching request is used to request the terminal device to switch from the second base station to the first base station.

[0072] In some implementations, the second startup information is carried in a first response message, the first response message is in response to a terminal device context query request message sent by the first base station to the second base station, and the first response message is used to indicate the context of the terminal device to the first base station. It should be understood that before receiving the first response message, the first base station sends a terminal device context query request message to the second base station, and the context query request message is used to query the context of the terminal device.

[0073] In combination with the eighth aspect, in certain implementations of the eighth aspect, the method also includes: within a first time period, no third indication information is sent, and the starting time of the first time period is when the third indication information is sent each time.

[0074] In the ninth aspect, a data transmission device is provided, which includes: a memory for storing programs; a processor for executing computer programs or instructions stored in the memory, and when the computer program or instructions stored in the memory are executed, the processor is used to execute the method provided in any one of the implementations of the first or fifth aspects above.

[0075] In one implementation, the apparatus is a source base station during a terminal device switching process.

[0076] In another implementation, the device is a chip, a chip system or a circuit in a source base station during a terminal device switching process.

[0077] In the tenth aspect, the present application provides a processor for executing the method provided by any one of the implementation modes of the first to fourth aspects above. In the process of executing these methods, the process of sending the above information and obtaining / receiving the above information in the above method can be understood as the process of outputting the above information by the processor, and the process of receiving the above information input by the processor. When outputting the above information, the processor outputs the above information to the interface and transmits it through the interface. After being output by the processor, the above information may also need to be processed in other ways before it reaches the interface. Similarly, when the processor receives the above information input, the interface obtains / receives the above information and inputs it into the processor. Furthermore, after the interface receives the above information, the above information may need to be processed in other ways before it is input into the processor.

[0078] For the operations involved, such as transmission, sending, and acquisition / reception, unless otherwise specified, or if they do not conflict with their actual functions or internal logic in the relevant descriptions, they can be understood as operations such as output and reception, input, etc., and can also be understood as transmission, sending, and receiving operations performed by radio frequency circuits and antennas. This application does not limit this.

[0079] In the implementation process, the processor may be a processor specifically used to execute these methods, or a processor that executes computer programs or instructions in a memory to execute these methods, such as a general-purpose processor. The memory may be a non-transitory memory, such as a read-only memory (ROM), which may be integrated with the processor on the same chip or may be separately arranged on different chips. The embodiment of the present application does not limit the type of memory and the arrangement of the memory and the processor.

[0080] In an eleventh aspect, a computer-readable storage medium is provided, which stores a program code for execution by a device, and the program code includes a method for executing any one of the implementations of the first to fourth aspects above.

[0081] In a twelfth aspect, a computer program product comprising instructions is provided. When the computer program product is run on a computer, the computer executes the method provided in any one of the implementations of the first to fourth aspects above.

[0082] In the thirteenth aspect, a chip is provided, which includes a processor and a communication interface. The processor reads instructions stored in a memory through the communication interface and executes the method provided in any one of the implementation modes of the first to fourth aspects.

[0083] Optionally, as an implementation method, the chip may also include a memory, in which a computer program or instruction is stored, and the processor is used to execute the computer program or instruction stored in the memory. When the computer program or instruction is executed, the processor is used to execute the method provided in any one of the implementation methods of the first to fourth aspects above. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] Figure 1 is a schematic diagram of a communication system provided in an embodiment of the present application;

[0085] Figure 2 is a schematic diagram of a 5G system based on a QoS architecture provided in an embodiment of the present application;

[0086] Figure 3 It is a schematic diagram of a flow chart of inter-station switching provided by an embodiment of the present application;

[0087] Figure 4 This is a schematic diagram of a process of inter-station switching of an XR service provided in an embodiment of the present application;

[0088] Figure 5 It is a flowchart of a data transmission method provided by an embodiment of the present application;

[0089] Figure 6 is a flowchart of another data transmission method provided in an embodiment of the present application;

[0090] Figure 7 It is a flowchart of another data transmission method provided in an embodiment of the present application;

[0091] Figure 8 This is a behavior flow diagram of a target base station provided in an embodiment of the present application;

[0092] Fig. 9 This is a schematic diagram of a behavior flow of a source base station provided in an embodiment of the present application;

[0093] Fig.10 is a flowchart of another data transmission method provided in an embodiment of the present application;

[0094] Fig.11 is a flowchart of another data transmission method provided in an embodiment of the present application;

[0095] Fig.12 It is a schematic diagram of the operation mode of the L4S mechanism provided in the embodiment of the present application;

[0096] Fig.13 is a flowchart of another data transmission method provided in an embodiment of the present application;

[0097] Fig.14 is a schematic diagram of a data transmission device 1400 provided in an embodiment of the present application;

[0098] Fig.15 is a schematic structural diagram of a data transmission device 1500 provided in an embodiment of the present application;

[0099] Fig.16 It is a schematic diagram of a chip system 1600 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0100] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0101] The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Global System of Mobile communication (GSM) system, Code Division Multiple Access (CDMA) system, Wideband Code Division Multiple Access (WCDMA) system, General Packet Radio Service (GPRS), Long Term Evolution (LTE) system, LTE Frequency Division Duplex (FDD) system, LTE Time Division Duplex (TDD), Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) communication system, fifth generation (5G) system or new radio (NR), and future evolved communication systems.

[0102] Figure 1 It is a schematic diagram of a communication system provided in an embodiment of the present application.

[0103] like Figure 1 As shown, the communication system using the solution of the embodiment of the present application may include an access network device, a terminal device and a core network. The communication system can be used for information exchange between the access network device and the core network, and can also be used for information exchange between access network devices. For example, Figure 1 As shown, both access network device #1 and access network device #2 can communicate with the core network through the NG interface. Access network device #1 and access network device #2 can communicate directly through the Xn interface, or access network device #1 and access network device #2 can communicate indirectly through the core network from the NG interface.

[0104] Terminal equipment, also known as user equipment (UE), mobile station (MS), mobile terminal (MT), etc., refers to equipment that provides voice and / or data connectivity to users. For example, the terminal equipment can be a mobile phone, a tablet computer (Pad), a computer with wireless transceiver function, a mobile Internet device (MID), a wearable device, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in self driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, a drone, a drone controller, etc. The embodiments of the present application do not limit the application scenarios. Terminal devices also include devices capable of sidelink communication, such as vehicle-mounted terminals, or handheld terminals capable of V2X (vehicle-to-everything) communication.

[0105] Access network equipment refers to the radio access network (RAN) node (or device) that connects the terminal to the wireless network, which can also be called a base station. For example, it can be an NR gNB or various types of base stations such as LTE eNB. For the sake of ease of description, the embodiments of the present application uniformly refer to "access network equipment" as "base station". Among them, NR gNB can adopt an architecture with a separation of centralized unit (CU) and distributed unit (DU), such as Figure 1 In the base station #1 shown, the CU and DU are connected via the F1 interface for message transmission; or the architecture of the CU and DU separation may not be adopted, such as Figure 1The base station #2 shown is not limited in the embodiments of the present application. In the separate deployment scenario where the access network equipment includes CU and DU, CU supports protocols such as radio resource control (RRC), packet data convergence protocol (PDCP), and service data adaptation protocol (SDAP); DU mainly supports radio link control layer (RLC), media access control layer (MAC) and physical layer protocols. Normally, a terminal device only maintains a data connection with one base station at the same time; in a dual connectivity (DC) scenario, a terminal device can be connected to two base stations at the same time, one of which serves as a control anchor point and provides control plane connection and user plane connection for the terminal, which is called the primary base station, and the other base station only provides user plane connection for the terminal, which is called the secondary base station. The present application may be applied to DC scenarios or not.

[0106] Core network equipment refers to equipment in the core network (CN) that provides service support for terminals. At present, some examples of core network equipment are: access and mobility management function (AMF) entity, session management function (SMF) entity, user plane function (UPF) entity, etc., which are not listed here one by one. Among them, the AMF entity can be responsible for terminal access management and mobility management; the SMF entity can be responsible for session management, such as user session establishment, etc.; the UPF entity can be a functional entity of the user plane, mainly responsible for connecting to the external network. It should be noted that the entity in this application can also be referred to as a network element or a functional entity. For example, the AMF entity can also be referred to as an AMF network element or an AMF functional entity. For another example, the SMF entity can also be referred to as an SMF network element or an SMF functional entity, etc.

[0107] In order to facilitate understanding of the solutions of the embodiments of the present application, the technical terms involved in the embodiments of the present application are described in detail below.

[0108] 1.PDU set

[0109] A collection of multiple data packets in the transport layer corresponds to the minimum granularity of data processing in the application layer. In some application scenarios, the application layer can only correctly parse the corresponding data unit if it correctly receives all the data packets in a PDU set. In other application scenarios, the application layer can parse the corresponding data unit if it correctly receives a certain proportion of the data packets in the PDU set.

[0110] 2.XR business

[0111] Extended Reality (XR) refers to various environments that combine reality and virtuality, as well as the interaction between people and machines, generated by computing technology and wearable devices. XR specifically includes the following typical forms: AR, VR and Mixed Reality (MR).

[0112] The 3rd Generation Partnership Project (3GPP) Rel-17 modeled and analyzed the service characteristics of XR. Usually, XR services will periodically generate data frames at a certain frame rate. For example, an AR service with a frame rate of 60fps (frames per second) generates 60 frames of video images per second, and a video frame appears approximately every 16.67ms. A video frame may be transmitted by multiple data packets, which may be divided into one or more PDU sets.

[0113] 3. Quality of Service (QoS)

[0114] Quality of service refers to a technology used to solve problems such as network delay and congestion. When the network is congested, data may be discarded. In order to meet users' requirements for different QoS for different applications, the network needs to be able to allocate and schedule resources according to user requirements and provide different QoS for different data.

[0115] 4.QoS flow

[0116] The 5G system forwards and processes data based on the granularity of QoS flows and guarantees its QoS.

[0117] The 5G core network establishes one or more protocol data unit sessions (PDU sessions) for a UE. A QoS flow is a data flow with the same source and destination addresses and the same QoS requirements within a PDU session. Figure 2 Schematic diagram of a 5G system based on QoS architecture provided by an embodiment of the present application. Figure 2As shown, a PDU session is established between the UE and the UPF, a wireless bearer is established between the UE and the NB, a core network tunnel is established between the NB and the UPF, and the PDU session includes multiple QoS flows, including a first QoS flow, a second QoS flow, and the like.

[0118] For downlink, 5GC maps packets with the same characteristics to the same QoS flow by identifying the characteristics of the packet, including the source Internet Protocol (IP) address, destination IP address, source port number, destination port number, and transport layer protocol number of the packet, and carries a QoS flow ID (QFI) in the packet header to identify which QoS flow the packet belongs to. For uplink, 5GC can explicitly or implicitly configure the mapping relationship between the above packet characteristics and QoS flow to the UE, and the UE will map the uplink data to be transmitted to different QoS flows.

[0119] The data of different QoS flows are independent of each other when transmitted in the 5G system. For each QoS flow, 5GC will send its QoS profile to the radio access network (RAN) to indicate its QoS requirements, such as packet delay budget (PDB), packet error rate (PER), etc., which indicates the expected service quality of the data of this QoS flow when it is transmitted in the 5G system. PDB represents the upper limit of the transmission delay of data packets between the core network and the UE. Data packets that are not correctly transmitted in the PDB are considered to be timed out. PER represents the upper limit of the packet error rate during the transmission of the QoS flow, that is, the proportion of data packets processed by the sender but not correctly received by the receiver. Specifically, the core network and the UE can be understood as starting from the UPF of the core network to the UE for downlink behavior; and starting from the UE to the UPF of the core network for uplink behavior.

[0120] For a PDU session, RAN will establish one or more data radio bearers (DRBs) for it and map each QoS flow to these DRBs for air interface transmission. Multiple QoS flows can be mapped to one DRB, but one QoS flow cannot be mapped to multiple DRBs. Usually, QoS flows with the same or similar QoS requirements will be mapped to the same DRB, thereby providing the same QoS guarantee on the air interface.

[0121] 5. QoS parameters of PDU

[0122] 5GC indicates the QoS requirements of different QoS flows to RAN through QoS profile, and these requirements are reflected through various QoS parameters. For example, common QoS parameters include PDB, PER, etc. The transmission network should try its best to ensure that the QoS requirements of the service are met to ensure user experience.

[0123] 6. QoS parameters for PDU set

[0124] XR services usually expect QoS guarantees at the granularity of PDU sets, which is determined by the encoding method of XR services. Since a PDU set corresponds to the smallest unit of application layer data processing, such as a video frame, for many applications, only when all data packets of this PDU set are correctly received can the receiving side successfully decode the video frame. Therefore, XR services require the transmission network to provide overall QoS guarantees for the PDU set to avoid the failure of decoding the entire video frame due to timeout or errors of some data packets in the PDU set.

[0125] 3GPP R18 (Release-18) designed new QoS parameters for XR services, called PDU set QoS parameters, including PDU set delay budget (PSDB), PDU set error rate (PSER) and PDU set integrated information (PSIHI). PSDB and PSER correspond to the traditional PDB and PER respectively. PSDB indicates the upper limit of the delay from the transmission of the first data packet in the PDU set between the core network and the UE to the completion of the transmission of the last data packet in the PDU set between the core network and the UE, that is, the upper limit of the transmission delay of the PDU set between the core network and the UE. The PDU set that is not fully transmitted correctly in the PSDB is considered to have timed out. PSER indicates the upper limit of the proportion of PDU sets that are not correctly transmitted during the transmission of the QoS flow, that is, the upper limit of the proportion of PDU sets that are processed by the sender but not correctly received by the receiver. PSIHI is a description of whether the QoS flow requires PDU set integrity. It indicates whether the application layer requires the receiving side to correctly receive all data packets in the PDU set when processing the PDU set. This is related to the specific implementation of the application.

[0126] In one implementation, the application can only correctly decode the PDU set after correctly receiving all the data packets in the PDU set. In this case, when transmitting the PDU set, the transmission network should try its best to ensure that all the data packets in the PDU set are correctly transmitted within the delay budget, because once a data packet times out or is lost, the receiving application layer cannot process the PDU set in time, resulting in a decrease in user experience. If it is determined that there is a data packet in the PDU set that cannot be transmitted in time and correctly, the sending side can also give up the transmission of the remaining data packets, because even if the remaining data packets are transmitted correctly, the application cannot process them, and actively giving up can save network resources. In another implementation, the application does not need to correctly receive all the data packets in the PDU set to decode the PDU set. For example, when the PDU set is processed by redundant coding on the sending side, the receiving side can completely restore the data of the PDU set as long as it receives a certain number or proportion of data packets. In this case, even if some data packets in the PDU set have timed out or been lost, the sending side should continue to transmit the remaining data packets because they are still useful to the application layer.

[0127] Through PDU set QoS parameters, the core network requires RAN to provide PDU set-based QoS flows (such as XR services) with PDU set granularity QoS guarantees, thereby improving XR user satisfaction.

[0128] 7. Handover

[0129] In the mobile communication system, when the UE obtains services from the 5G network, it may need to change the serving cell due to a change in location. The process of a connected UE changing its serving cell is called handover. The handover process is controlled by the base station, that is, the base station sends a handover message to instruct the UE when and which cell to switch to. Usually, the base station decides whether to switch and which cell to switch to based on the signal quality that each cell can provide to the UE.

[0130] When the source cell (i.e., the cell where the UE is originally located) and the target cell (i.e., the cell to which the UE is to be switched) are located in different base stations, this type of handover is called inter-base station handover. Depending on the type of interface between the source base station and the target base station, it can be divided into Xn handover and NG handover.

[0131] Figure 3 It is a flow chart of an inter-station switching process provided in an embodiment of the present application.

[0132] like Figure 3 As shown in (a), when an Xn interface exists between the source base station and the target base station, switching based on the Xn interface can be performed.

[0133] S311, the source base station sends a handover request (HANDOVER REQUEST) #1 to the target base station.

[0134] The handover request #1 is used to indicate that the UE wishes to handover to the target cell. The handover request carries the configuration requirement information of the UE, for example, the PDU session and QoS flow established by the UE, and the QoS requirements of these QoS flows.

[0135] S312, the target base station performs admission control according to the cell load, capability, etc., and determines the handover request feedback message #1.

[0136] The handover request feedback message #1 is used to indicate whether to accept the handover UE, and which PDUsessions or QoS flows of the UE are accepted.

[0137] It should be understood that when the target base station agrees to the handover request #1, the type of the handover request feedback message #1 is a handover request confirmation message (HANDOVER REQUEST ACKNOWLEDGE). When the target base station disagrees with the handover request #1, the type of the handover request feedback message #1 is a handover preparation failure message (HANDOVER PREPARATION FAILURE).

[0138] S313, the target base station sends a handover request feedback message #1 to the source base station.

[0139] S314: When the target base station accepts the handover UE, the source base station sends a handover command #1 to the UE, wherein the handover command #1 is used to instruct the UE to access the target cell.

[0140] S315, the source base station no longer transmits data with the UE, and sends the buffered data #1 to the target base station.

[0141] The cache data #1 is the data that is already in the source base station cache and should be sent to the UE.

[0142] S316, after receiving the instruction, the UE performs handover and successfully accesses the target cell.

[0143] S317, the terminal device and the target base station complete the target cell access.

[0144] That is, the terminal device continues to transmit data in the target cell, that is, the core network sends subsequent downlink data to the UE through the target base station, and the UE's uplink data is also sent to the core network through the target base station.

[0145] like Figure 3As shown in (b), when there is no Xn interface between the source base station and the target base station, the switching request and confirmation message cannot be directly transmitted between the base stations. At this time, a switching based on the NG interface is required to forward the above message through the core network.

[0146] S321a, the source base station sends a handover request #2 to the core network. S321b, the core network sends a handover request #3 to the target base station.

[0147] Among them, the functions and effects of switching request #2, switching request #3 and switching request #1 are similar and will not be elaborated here.

[0148] S322, the target base station performs admission control according to the cell load, capability, etc., and determines the handover request feedback message #2.

[0149] Among them, the switching request feedback message #2 and the switching request feedback message #1 have similar functions, which will not be described here in detail.

[0150] S323, the target base station sends a switching request feedback message #2 to the core network.

[0151] S324a, when the target base station accepts the handover UE, the core network sends a handover command #2 to the source base station. S324b, the source base station sends a handover command #3 to the terminal device.

[0152] The handover command #2 is used to instruct the source base station to continue the handover operation, and the handover command #3 is used to instruct the UE to handover to the target cell.

[0153] S325a, the source base station no longer performs data transmission with the UE, and sends the buffered data #2 to the core network. S325b, the core network sends the buffered data #2 to the target base station.

[0154] The cache data #2 is data that is already in the source base station cache and should be sent to the UE.

[0155] S326, after receiving the instruction, the UE performs handover and successfully accesses the target cell.

[0156] S327, the terminal device and the target base station complete the target cell access.

[0157] That is, the terminal device continues to transmit data in the target cell, that is, the core network sends subsequent downlink data to the UE through the target base station, and the UE's uplink data is also sent to the core network through the target base station.

[0158] It should be understood that the information transmission method between the source base station and the target base station can be to realize direct communication between the source base station and the target base station through the Xn interface, or, it can also realize indirect communication between the source base station and the target base station through the NG interface and forwarding through the core network.

[0159] At present, since the XR service requires QoS guarantee based on the granularity of PDU set, the corresponding base station needs to support data processing and forwarding based on PDU set. Furthermore, during downlink transmission, when the QoS flow requires QoS guarantee based on PDU set and the base station supports PDU set processing, the core network will add relevant information of the PDU set to the header of each data packet when transmitting the data packet to the base station. The relevant information can be used to identify the PDU set or reflect the attributes of the PDUset. For example, the PDU set sequence number, the sequence number of the PDU in the PDU set, the PDU set size, the PDU set importance, etc., so that the base station can distinguish which PDU set different data packets belong to. If the base station does not support PDU set processing, the core network does not need to add this information. Therefore, the core network needs to know the capability information of whether the base station supports PDU set processing.

[0160] Specifically, if the base station receives a QoS profile of a QoS flow that contains QoS parameters of a PDU set, the base station reports to the core network whether it supports processing the PDU set.

[0161] Figure 4 : is a flow chart of inter-station switching of an XR service provided in an embodiment of the present application. Figure 4 The source base station supports processing PDU set, but the target base station does not support processing PDU set. The terminal device is running XR service (for example, receiving XR video from XR server) and expects that the data of XR service can obtain QoS guarantee based on PDU set. Figure 4 The source base station and the target base station shown can communicate directly via an Xn interface.

[0162] S401, the core network sends the QoS guarantee requirement of PDU set to the source base station.

[0163] The QoS guarantee requirement may include a QoS profile of the QoS parameters of the PDU set.

[0164] S402: The source base station sends capability indication information to the core network according to the QoS configuration file. The capability indication information is used to indicate that the source base station has a PDU set processing capability.

[0165] S403, the core network sends first XR data to the source base station, where the first XR data includes relevant information of the PDU set.

[0166] The relevant information of the PDU set may be carried in the header of the data packet in the QoS flow where the first XR data is located. The relevant information of the PDU set, for example, the PDU set sequence number, the sequence number of the PDU in the PDU set, the PDU set end identifier, the data burst end identifier, the PDU set size, the PDU set importance, etc.

[0167] S404: The source base station processes the first XR data according to the relevant information of the PDU set.

[0168] It should be understood that the source base station identifies the relevant information of the PDU set in the first XR data to determine which PDU set the first XR data corresponds to, and provides scheduling processing based on the PDU set to ensure its PDU set QoS requirements. The relevant information of the PDU set has been described in detail above and will not be repeated here.

[0169] S405: The source base station sends the processed first XR data to the terminal device.

[0170] The terminal device is currently in a source cell under a source base station. Assuming that the terminal device moves, the terminal device expects to switch to a target cell under a target base station.

[0171] S406: The source base station sends a handover request #3 to the target base station. The handover request #3 includes a QoS profile of the QoS flow where the first XR data is located, including QoS parameters of the PDU set.

[0172] S407: When the target base station does not support processing of the PDU set, the target base station sends capability indication information to the core network, where the capability indication information is used to indicate that the target base station does not support processing of the PDU set.

[0173] It should be understood that the core network device's knowledge of the capability indication information of the target base station helps the core network to send data to the target base station in a more targeted manner.

[0174] S408, the target base station performs admission control according to the cell load, capability, etc., and determines the handover request feedback message #3.

[0175] Among them, the switching request feedback message #3 and the switching request feedback message #1 have similar functions, which will not be described here in detail.

[0176] S409, the source base station sends a handover command #3 to the UE, wherein the handover command #3 is used to instruct the UE to access the target cell.

[0177] S410, the source base station no longer transmits data with the UE, and sends the buffered data #3 to the target base station.

[0178] The cached data #3 is the first XR data that has been cached in the source base station. Therefore, the data packet header of the cached data #3 carries relevant information of the PDU set.

[0179] S411, the terminal device and the target base station complete the target cell access.

[0180] S412, the target base station sends a switching completion message to the core network.

[0181] S413, the core network sends second XR data to the target base station, where the second XR data does not include relevant information of the PDU set.

[0182] It should be understood that since the target base station does not support processing PDU set, the data transmission between the core network and the target base station falls back to the traditional PDU-based transmission mode. That is, the second XR data includes relevant information about the PDU, rather than relevant information about the PDU set.

[0183] S414: The target base station processes the second XR data according to the relevant information of the PDU.

[0184] S415: The target base station sends the processed second XR data to the terminal device.

[0185] The difference in whether base stations support processing PDU sets is mainly due to the differences in base station capabilities and upgrades in actual networks. Although the above scheme has taken into account the fact that different base stations may have different capabilities to support processing PDU sets, and has designed corresponding schemes to enable the base stations to notify the core network of this capability, so that the core network can reasonably decide whether to provide QoS guarantees based on PDU sets for the QoS flow and whether to add PDU set related information to the data packets in the QoS flow. However, before the target base station and the terminal device transmit data, since the data originally cached in the source base station needs to be forwarded to the target base station, there may be a mismatch between the cached data and the capabilities of the target base station, such as Figure 4 As shown. Therefore, this may cause the relevant information of the PDU set carried in the packet header of the cached data to be useless to the target base station, but the relevant information of the PDU set occupies the resources of the forwarding link (for example, the Xn link or the NG link), resulting in a waste of resources. Even the target base station may be confused or misunderstood due to not understanding the meaning of this information, causing some unknown errors.

[0186] In view of the above problems, the present application provides a data transmission method and device. Figures 5 to 15 Detailed description.

[0187] Figure 5 1 is a flow chart of a data transmission method provided in an embodiment of the present application. The method is applied to a source base station during a terminal device switching process.

[0188] S510. The source base station sends a first handover request, where the first handover request includes QoS parameters of a PDU set.

[0189] The QoS parameters include one or more of the protocol data unit set delay budget PSDB, the protocol data unit set error rate PSER and the protocol data unit set integrity information PSIHI. It should be understood that the specific meanings of these parameters have been given in the above content and will not be repeated here.

[0190] As a possible implementation manner, the source base station directly sends the first switching request to the target base station during the switching process of the terminal device through the Xn interface.

[0191] As a possible implementation method, the source base station sends a first switching request to the core network through the NG interface. The core network can send the first switching request to the target base station through the NG interface, or the core network can send the processed first switching request to the target base station through the NG interface.

[0192] S520, the source base station receives first indication information, where the first indication information is used to indicate the processing capability of the target base station for the PDU set during the terminal device switching process.

[0193] As a possible implementation manner, the source base station may directly receive the first indication information from the target base station through an Xn interface.

[0194] As a possible implementation manner, the target base station may send the first indication information to the core network through the NG interface, and the core network sends the first indication information to the source base station through the NG interface.

[0195] It should be understood that the first indication information may be in an independent message, or may be carried in a first feedback message in response to the first switching request. The present application embodiment does not limit this, and the details will be described in Figure 6 Expand the description.

[0196] S530: The source base station performs a switching operation according to the first indication information.

[0197] As a possible implementation manner, when the first indication information indicates that the target base station has the processing capability of the PDU set, the source base station sends a first cache data packet, and the first cache data packet includes relevant information of the PDU set.

[0198] It should be understood that the relevant information of the PDU set has been described in detail in the above content and will not be repeated here.

[0199] As a possible implementation method, when the first indication information indicates that the target base station does not have the processing capability of the PDU set, a second cache data packet is sent, and the second cache data packet does not include relevant information of the PDU set; or, a new target base station is determined; or, a second switching request is sent to the target base station, and the second switching request does not include the QoS parameters of the PDU set.

[0200] In the above technical solution, the source base station fully considers the processing capability of the target base station for PDU set and makes reasonable switching decisions, thereby avoiding the waste of link resources and even data decoding errors caused by the mismatch of the processing capability of the two base stations for PDU set. For example, if the target base station does not support PDU set processing, and there are other optional switching base stations in the surrounding area, in order for the terminal device to continue to enjoy the QoS guarantee based on PDU set, the source base station can try to switch to other base stations. Even if the terminal device has no other choice but to switch to the current target base station, the source base station can also optimize the forwarded data packets during subsequent cache data forwarding, and remove the PDU set information carried in its packet header, thereby reducing the resource consumption of the forwarding link and improving the forwarding efficiency.

[0201] The following will be combined Figures 6 to 11 A more specific implementation method for the source base station to learn whether other base stations have the PDU set processing capability is described in detail.

[0202] Figure 6 It is a flowchart of another data transmission method provided in an embodiment of the present application. Figure 6 The interaction diagram shown in the example uses the source base station and the target base station in the terminal device switching process as the execution subject of the interaction diagram to illustrate the corresponding method, but the present application does not limit the execution subject of the interaction diagram. Figure 6 The source base station in the method may also be a chip, a chip system or a processor that supports the source base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the source base station. Figure 6 The target base station in the description may also be a chip, a chip system or a processor that supports the target base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the target base station.

[0203] S601: The source base station sends a first handover request to the target base station, where the first handover request includes QoS parameters of a PDU set.

[0204] The first switching request is used to request the terminal device to switch from the source base station to the target base station. It should be understood that the terminal device requires QoS guarantee based on PDU set.

[0205] It should be understood that the specific content of the QoS parameters of the PDU set has been described in detail above. The QoS parameters of the PDU set may include one or more of the PDU set delay budget PSDB, the PDU set error rate PSER and the PDU set integrity information PSIHI.

[0206] S602: The target base station performs admission control in response to the first handover request.

[0207] It should be understood that after admission control, the target base station has confirmed the information related to the first handover request.

[0208] The information related to the first switching request may include at least one of the following information: whether the first switching request is approved, whether the QoS flow is accepted, and whether the processing capability of the PDU set is available.

[0209] The QoS flow is a QoS flow with a QoS requirement of a PDU set.

[0210] It should be understood that the target base station may not consider the processing capability of the target base station for the PDU set when confirming whether to agree to the first switching request and / or whether to accept the QoS flow. For example, only the current load condition and / or current resource usage of the target base station may be considered. Alternatively, the target base station may also take into account its processing capability for the PDU set to determine whether to agree to the first switching request and / or whether to accept the QoS flow.

[0211] Method 1: The target base station sends the indication information of whether it has the processing capability of the PDU set through a separate message.

[0212] S603a-1, the target base station sends first indication information to the source base station, where the first indication information is used to indicate the processing capability of the target base station for the PDU set.

[0213] In other words, the first indication information is used to indicate whether the target base station has the processing capability of the PDU set.

[0214] S603a-2, the target base station sends a first feedback message to the source base station, the first feedback message is used to indicate whether the first handover request is approved. Optionally, the first feedback message may also indicate whether the QoS flow is accepted.

[0215] The QoS flow is a QoS flow with a QoS requirement of a PDU set.

[0216] As a possible implementation, when the message type of the first feedback message is a handover request confirmation message, the first feedback message is used to indicate approval of the first handover request. When the message type of the first feedback message is a handover preparation failure message, the first feedback message is used to indicate disapproval of the first handover request.

[0217] It should be understood that the embodiments of the present application do not limit the execution order of S603a-1 and S603a-2. For example, S603a-1 may be executed first, and then S603a-2. For another example, S603a-2 may be executed first, and then S603a-1. In this example, the target base station may first execute S603a-2 based on factors other than the PDU set processing capability. For example, the current load or currently available resources of the target base station determine the indication information of the first feedback message, for example, determine whether the first feedback message agrees to the first switching request. Then, when the first feedback message indicates agreement to the first switching request or disagreement to the first switching request, S603a-1 is executed.

[0218] Method 2: The target base station carries indication information of whether it has the processing capability of the PDU set in the first feedback message.

[0219] S603b: The target base station sends a first feedback message to the source base station, where the first feedback message includes first indication information, and the first indication information is used to indicate whether the target base station has a processing capability of the PDU set.

[0220] Optionally, other specific information indicated in the first feedback message may refer to S603a-2, which will not be described in detail here.

[0221] As a possible implementation, the first indication information is used to indicate that the target base station has the processing capability of the PDU set, that is, the target base station supports the PDU set processing. The first feedback message is used to indicate that the target base station agrees to the first switching request. Optionally, the first feedback message is also used to indicate that the target base station accepts the QoS flow.

[0222] For example, the first indication information may include an indication field, and when the indication field is a first value, the first indication information is used to indicate that the target base station has the processing capability of the PDU set. The embodiment of the present application does not impose any restrictions on the specific value of the first value, and the corresponding meanings of the first value for the source base station and the target base station are consistent.

[0223] As a possible implementation, the first indication information is used to indicate that the target base station does not have the processing capability of the PDU set, that is, the target base station does not support PDU set processing. The first feedback message is used to indicate that the target base station agrees to the first switching request. Optionally, the first feedback message is also used to indicate that the target base station accepts the QoS flow.

[0224] As a possible implementation, the first indication information is used to indicate that the target base station does not have the processing capability of the PDU set, that is, the target base station does not support PDU set processing. The first feedback message is used to indicate that the target base station agrees to the first switching request. Optionally, the first feedback message is also used to indicate that the target base station does not accept the QoS flow.

[0225] Exemplarily, the first indication information is used to indicate that the target base station does not have the processing capability of the PDU set, that is, the target base station does not support PDU set processing. The first feedback message is used to indicate that the target base station agrees to the first handover request. The first feedback message is also used to indicate that the target base station does not accept the QoS flow.

[0226] The reason why the target base station does not accept the QoS flow is that the target base station does not support PDU set processing.

[0227] For example, the first indication information may include an indication field, and when the indication field is a second value, the first indication information is used to indicate that the target base station does not have the processing capability of the PDU set. The embodiment of the present application does not impose any restrictions on the specific value of the second value, and the corresponding meanings of the second value for the source base station and the target base station are consistent.

[0228] For another example, the first feedback message may include a QoS flow not admitted list, and the QoS flow not admitted list may include a quality of service flow identity (QFI) corresponding to the QoS flow not admitted. The QoS flow not admitted list may also include a first cause field, and the first cause field may be a first indication information. When the first cause field is a third value, the first cause field is used to indicate that the target base station does not have the processing capability of the PDU set. In this case, the first indication information is carried in the first feedback message, and the cause field is a possible specific form of expression of the first indication information. It should also be understood that the embodiment of the present application does not impose any restrictions on the value of the third value, and the corresponding meanings of the value of the third value for the source base station and the target base station are consistent.

[0229] In the case where the target base station agrees to the first handover request, the first feedback message may also be referred to as a first handover request confirmation message, that is, the type of the first feedback message is a handover request confirmation message.

[0230] In a possible implementation, the first indication information is used to indicate that the target base station does not have the processing capability of the PDU set, that is, the target base station does not support PDU set processing. The first feedback message is used to indicate that the target base station does not agree to the first switching request. Optionally, the first feedback message is also used to indicate that the target base station does not accept the QoS flow.

[0231] In the case that the target base station does not agree to the first handover request, the first feedback message may also be referred to as a first handover preparation failure message. That is, the type of the first feedback message is a handover preparation failure message.

[0232] For example, the first switching preparation failure message includes a second reason field, and the second reason field can be the first indication information. When the second reason field is the fourth value, the second reason field is used to indicate that the target base station does not have the processing capability of the PDU set. In this case, the first indication information is carried in the first feedback message, and the reason field is a possible specific form of expression of the first indication information. It should also be understood that the embodiment of the present application does not impose any restrictions on the value of the fourth value, and the corresponding meanings of the fourth value for the source base station and the target base station are consistent.

[0233] For another example, the first indication information may include an indication field, and when the indication field is a second value, the first indication information is used to indicate that the target base station does not have the processing capability of the PDU set.

[0234] It should be understood that in the above S603a-1, S603a-2 or S603b, part or all of the information related to the first handover request is made known to the source base station.

[0235] It should also be understood that the above S603a-1, S603a-2 or S603b is based on the communication between the source base station and the target via the Xn interface as an example, and the target base station can also let the source base station know the information in the above S603a-1, S603a-2 or S603b through the core network via the NG interface. This implementation is not shown in the attached figure, and the specific interaction method can be referred to Figure 3 (b).

[0236] S604: The source base station performs a first operation according to the first indication information.

[0237] The first operation may be understood as a switching operation related to inter-station switching. S604a to S604d are four possible first operations.

[0238] As a possible implementation manner, when the first indication information indicates that the target base station has the processing capability of the PDU set, S604a may be executed.

[0239] As a possible implementation manner, when the first indication information indicates that the target base station does not have the processing capability of the PDU set, S604b, S604c or S604d may be executed.

[0240] In the above technical solution, the source base station fully considers the processing capability of the target base station for the PDU set, thereby avoiding the waste of link resources and even data decoding errors caused by the mismatch of the processing capabilities of the two base stations for the PDU set.

[0241] First operation #1: S604a, the source base station sends first buffered data to the target base station, where the first buffered data includes relevant information of the PDUset.

[0242] For example, the execution condition of the first operation #1 may be that the first indication information indicates that the target base station has the PDU set processing capability. Alternatively, the execution condition may also be that the first indication information indicates that the target base station has the PDU set processing capability, the first feedback message indicates that the target base station agrees to the first switching request, and the first feedback message is also used to indicate the acceptance of the QoS flow.

[0243] In this way, when the first indication information indicates that the target base station has the PDU set processing capability, the source base station directly forwards the cached data to be forwarded to the target base station. Compared with the source base station directly forwarding the cached data to the target base station when the capability of the target base station is unknown, the solution of the present application can ensure that there is no waste of link resources when forwarding the cached data.

[0244] First operation #2: S604b, the source base station sends second buffered data to the target base station, and the second buffered data does not include relevant information of the PDU set.

[0245] Before sending the second buffered data, the source base station removes the relevant information of the PDU set in the data packet header of the buffered data to be forwarded. The relevant information of the PDU set has been described in detail above and will not be repeated here.

[0246] For example, the execution condition of the first operation #2 may be that the first indication information indicates that the target base station does not have the PDU set processing capability. Alternatively, the execution condition may also be that the first indication information indicates that the target base station does not have the PDU set processing capability, and the first feedback message is used to indicate approval of the first switching request.

[0247] In this way, when the first indication information indicates that the target base station does not have the PDU set processing capability, the source base station can reduce the packet header size of the forwarded data while ensuring that the inter-station switching process between the source base station and the target base station remains unchanged, thereby reducing the consumption of forwarding link resources.

[0248] First operation #3: S604c, the source base station determines a new target base station.

[0249] That is, the source base station may abandon the subsequent switching steps and try to find other base stations that support PDU set processing to re-initiate the switching.

[0250] For example, the execution condition of the first operation #3 may be case one: the first indication information indicates that the target base station does not have the PDU set processing capability. Alternatively, the execution condition may also be case two: the first indication information indicates that the target base station does not have the PDU set processing capability, the first feedback message is used to indicate the approval of the first switching request, and the first feedback message is also used to indicate the acceptance of the QoS flow. Alternatively, the execution condition may also be case three: the first indication information indicates that the target base station does not have the PDU set processing capability, the first feedback message is used to indicate the approval of the first switching request, and the first feedback message is also used to indicate the non-acceptance of the QoS flow. Alternatively, the execution condition may also be case four: the first indication information indicates that the target base station does not have the PDU set processing capability, and the first feedback message is used to indicate the disapproval of the first switching request.

[0251] In this way, when the first indication information indicates that the target base station does not have the PDU set processing capability, by finding a more suitable new target base station, the capabilities of the two base stations for inter-station switching can be matched, ensuring the QoS guarantee based on the PDU set, which is more suitable for the data transmission process based on the PDU set.

[0252] First operation #4: S604d, the source base station sends a second handover request to the target base station, and the second handover request does not include the QoS parameter of the PDU set.

[0253] In other words, the source base station continues to send a second handover request to the target base station. The difference between the second handover request and the first handover request is that the second handover request does not include the QoS parameters of the PDU set. That is, the source base station removes the QoS parameters of the PDU set from the QoS configuration file of the QoS flow requiring the PDU set, and reverts the QoS flow to a common QoS flow based on the PDU granularity QoS requirement before sending a handover request to the target base station.

[0254] Optionally, when the target base station indicates to the source base station that it agrees with the second handover request, the relevant information of the PDU set in the buffer data to be forwarded is removed before forwarding.

[0255] For example, the execution condition of the first operation #4 may be that the first indication information indicates that the target base station does not have the PDU set processing capability. Alternatively, the execution condition may also be that the first indication information indicates that the target base station does not have the PDU set processing capability, the first feedback message is used to indicate that the first switching request is approved, and the first feedback message is also used to indicate that the QoS flow is not accepted. Alternatively, the execution condition may be that the first indication information indicates that the target base station does not have the PDU set processing capability, and the first feedback message is used to indicate that the first switching request is not approved.

[0256] In this way, when the first indication information indicates that the target base station does not have the PDU set processing capability, the inter-station switching between the source base station and the target base station can continue to be implemented, thereby avoiding problems such as service interruption caused by the terminal not being able to switch in time. At the same time, the packet header size of the forwarded data is also reduced, thereby reducing the consumption of forwarding link resources.

[0257] It should be understood that the above S604a, S604b or S604d is based on the communication between the source base station and the target via the Xn interface. The source base station can also perform the above S604a, S604b or S604d steps between the core network and the target base station from the NG interface. This implementation is not shown in the accompanying drawings. For specific interaction methods, please refer to Figure 3 (b).

[0258] Figure 7 It is a flowchart of another data transmission method provided in an embodiment of the present application. Figure 7 The interaction diagram of FIG. 1 also uses the source base station and the target base station as the execution subjects of the interaction diagram during the terminal device switching process to illustrate the corresponding method, but the present application does not limit the execution subjects of the interaction diagram. For example, Figure 7 The source base station in the method may also be a chip, a chip system or a processor that supports the source base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the source base station. Figure 7 The target base station in the description may also be a chip, a chip system or a processor that supports the target base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the target base station.

[0259] It should be understood that since the PDU set related technology was introduced in 3GPP R18, there may be some base stations in the actual network that have not been upgraded to R18. Figure 7 The target base station in is the base station that has not been upgraded, and can also be called the old base station. Figure 7 The source base station in is an upgraded base station, which can also be called a new base station.

[0260] S701: The source base station sends a fourth handover request to the target base station, where the fourth handover request includes QoS parameters of a PDU set.

[0261] It should be understood that the function of the fourth handover request and the QoS parameters for the PDU set included therein are similar to those of the first handover request, and are not described in detail herein. Figure 6 .

[0262] S702: The target base station performs admission control in response to the fourth handover request.

[0263] It should be understood that since the target base station is an old base station that has not been upgraded, the target base station cannot identify the meaning of the parameters for the PDU set in the fourth switching request.

[0264] After admission control, the target base station determines a second feedback message.

[0265] It should be understood that since the target base station is an old base station, when determining the second feedback message, the target base station considers factors related to its own capabilities, such as the current load of the target base station, the current available resources, etc.

[0266] The type of the second feedback message may be a handover request confirmation message or a handover preparation failure message.

[0267] S703, the target base station sends a second feedback message to the source base station, the second feedback message is used to indicate whether the target base station agrees to the fourth switching request, and optionally, the second feedback message is also used to indicate whether to accept the QoS flow, wherein the QoS flow is a QoS flow with QoS requirements of PDU set.

[0268] It should be understood that Figure 7 The second feedback message and Figure 6 The contents of S603a-2 may be similar. For details, please refer to S603a-2, which will not be described in detail here.

[0269] That is, if the target base station is an old base station, the second feedback message does not include indication information of whether the target base station has the processing capability for the PDU set.

[0270] As a possible implementation manner, the second feedback message is used to indicate that the target base station agrees with the fourth handover request. Optionally, the second feedback message is also used to indicate that the QoS flow is accepted.

[0271] As a possible implementation manner, the second feedback message is used to indicate that the target base station agrees with the fourth handover request. Optionally, the second feedback message is also used to indicate that the target base station does not accept the QoS flow.

[0272] For example, the second feedback message may include a list of unaccepted QoS flows, and the list of unaccepted QoS flows may include the QFI corresponding to the unaccepted QoS flows. The list of unaccepted QoS flows may also include a third reason field, and the third reason field may be a specific reason, or others. The specific reason corresponding to the third reason field may be the capability of the target base station, for example, the current load of the target base station is too heavy, or the target base station has no available resources, etc.

[0273] As a possible implementation manner, the second feedback message is used to indicate that the target base station does not agree to the fourth handover request. The second feedback message may also include a fourth reason field, and the fourth reason field may be a specific reason, or other. The specific reason corresponding to the fourth reason field may be the capability of the target base station, for example, the current load of the target base station is too heavy, or the target base station has no available resources, etc.

[0274] S704: The source base station determines whether the target base station is an old base station according to the second feedback message.

[0275] It should be understood that it is unknown whether the source base station has upgraded the target base station. The source base station can determine that the target base station is an old base station because the second feedback message does not include feedback information indicating the processing capability for the PDU set, that is, it determines that the old base station does not have the processing capability for the PDU set.

[0276] S705: Execute the second operation.

[0277] The second operation can be understood as a switching operation related to inter-station switching. S705a to S705c are three possible second operations.

[0278] Second operation #1: S705a, the source base station sends fourth cache data to the target base station, and the fourth cache data does not include relevant information of the PDU set.

[0279] For example, the execution condition of the second operation #1 may be that the second feedback message is used to indicate that the fourth switching request is approved. Alternatively, the second feedback message may be used to indicate that the fourth switching request is approved and the QoS flow is admitted.

[0280] In this way, when the target base station is an old base station, the source base station can reduce the packet header size of the forwarded data while ensuring that the inter-station switching process between the source base station and the old base station that has not been upgraded remains unchanged, thereby reducing the consumption of forwarding link resources.

[0281] Second operation #2: S705b, the source base station determines a new target base station.

[0282] It should be understood that if the target base station is determined to be an old base station in S704 and the old base station does not have the processing capability for the PDU set, then the source base station may determine a new target base station.

[0283] As a possible implementation manner, the source base station may abandon subsequent switching steps and try to find other base stations that support PDUset processing to re-initiate switching.

[0284] For example, in this implementation, the execution condition of the second operation #2 may be case 1: the second feedback message may be used to indicate the approval of the fourth switching request and the acceptance of the QoS flow. Case 2: the second feedback message may be used to indicate the approval of the fourth switching request, and the second feedback message may also be used to indicate the non-acceptance of the QoS flow, wherein the list of non-accepted QoS flows included in the second feedback message may also include a third reason field, and the third reason field is used to indicate other reasons. That is, the second feedback message indicates that the target base station does not accept the QoS flow, but the specific reason why the target base station does not accept the QoS flow is not fed back. Case 3: the second feedback message may be used to indicate the disapproval of the fourth switching request, wherein the second feedback message may also include a fourth reason field, and the fourth reason field is used to indicate other reasons. That is, the second feedback message indicates that the target base station does not agree to the switching request, but the specific reason why the target base station does not agree to the switching request is not fed back.

[0285] As a possible implementation manner, the source base station may abandon the subsequent switching steps and determine a new target base station according to the reason for not agreeing to the fourth switching request or not accepting the QoS flow.

[0286] For example, in this implementation, the execution condition of the second operation #2 may be: the second feedback message is used to indicate that the fourth switching request is not agreed to and / or the QoS flow is not accepted, wherein the second feedback message may also include a third reason field or a fourth reason field, and the third reason field or the fourth reason field is used to indicate reasons related to the capabilities of the target base station, for example, the target base station is currently overloaded or has no available resources.

[0287] In this implementation manner, the determined new target base station may be a new target base station with a light load, or may be a new target base station with sufficient available resources.

[0288] Second operation #3: S705c, the source base station sends a fifth handover request to the target base station, and the fifth handover request does not include the QoS parameter of the PDU set.

[0289] It should be understood that the fifth switching request in S705c and Figure 6 The second switching request in is similar and will not be described here.

[0290] For example, the execution condition of the second operation #3 may be that the second feedback message is used to indicate that the fourth switching request is not approved and / or the QoS flow is not admitted.

[0291] In this way, when the target base station is an old base station that has not been upgraded, the inter-station switching between the source base station and the old base station can continue to be realized, thereby saving and avoiding problems such as service interruption caused by the terminal not being able to switch in time. At the same time, it also reduces the size of the forwarding data header, thereby reducing the consumption of forwarding link resources.

[0292] It should be understood that the above S701, S703, S705a, S705b and S705c are based on the communication between the source base station and the target through the Xn interface. The source base station can also perform the above S701, S703, S705a, S705b and S705c steps between the core network and the target base station from the NG interface. This implementation is not shown in the accompanying drawings. For specific interaction methods, please refer to Figure 3 (b).

[0293] The following combines 8 and Fig. 9 From the perspective of the target base station, a possible process of determining a feedback message in response to a handover request in the admission control process is described, and from the perspective of the source base station, a possible process of determining a handover operation is described.

[0294] Figure 8 is a schematic diagram of a behavior flow of a target base station provided in an embodiment of the present application. It should be understood that Figure 8 It is a comprehensive description of whether the target base station is a new base station or an old base station.

[0295] S801: Determine whether the target base station is a new base station.

[0296] If the target base station is an old base station, S802, the target base station determines that the second feedback message is used to indicate whether to approve the fourth handover request and / or whether to accept the QoS flow.

[0297] The second feedback message does not include the first indication information, that is, it does not include feedback information on whether the old base station has the processing capability for the PDU set. Figure 7 .

[0298] If the target base station is a new base station, S803, determine whether the target base station accepts the QoS flow.

[0299] If the target base station accepts the QoS flow, S804 determines whether the target base station has the processing capability of the PDU set.

[0300] If the target base station has the processing capability of the PDU set, S805, the target base station determines first indication information to indicate support for processing the PDU set.

[0301] If the target base station does not have the capability to process the PDU set, S806, the target base station determines first indication information to indicate that the processing of the PDU set is not supported.

[0302] At this time, the first feedback message may be used to indicate that the first switching request is approved and the QoS flow is admitted.

[0303] It should be understood that there is no order restriction for the determination of S803 and S804. Figure 8 This description is for exemplary purposes only.

[0304] If the target base station does not accept the QoS flow, S807 , it is determined whether the reason for the target base station to refuse to accept the QoS flow is that it does not have the processing capability for the PDU set.

[0305] Optionally, the target base station can also determine whether to agree to the first switching request. The factors considered for the first switching request may be the processing capability of the target base station for the PDU set or other capabilities of the target base station, such as the load condition of the target base station and the available resources of the target base station.

[0306] If the reason why the target base station rejects the QoS flow is that the target base station does not have the processing capability for the PDU set, S808, the first indication information determined by the target base station indicates that the processing of the PDU set is not supported.

[0307] At this time, the first feedback message may be used to indicate that the first switching request is approved and the QoS flow is not admitted. Alternatively, the first feedback message may also be used to indicate that the first switching request is not approved.

[0308] If the reason for the target base station to reject the QoS flow is not that the target base station does not have the processing capability for the PDU set, S809, the first feedback message determined by the target base station is used to indicate other reasons. Alternatively, in addition to determining the first feedback message, the target base station may also determine the first indication information to indicate whether the PDU set is not supported.

[0309] At this time, the first feedback message may also be used to indicate that the target base station agrees to the first handover request and does not accept the QoS flow. Alternatively, the first feedback message may also be used to indicate that the target base station does not agree to the first handover request.

[0310] The first feedback message determined by the target base station in S803 to S809 may include the first indication information or may not include the first indication information. Figure 6 .

[0311] Fig. 9 is a schematic diagram of a behavior flow of a source base station provided in an embodiment of the present application. It should be understood that Fig. 9 It is a comprehensive description of the switching operation after the source base station receives different feedback messages.

[0312] S901: The source base station determines whether first indication information is received.

[0313] The first indication information is used to indicate whether the target base station has the processing capability for the PDU set.

[0314] If the source base station determines that the first indication information is received, S902, determines whether the target base station supports PDU set processing according to the first indication information.

[0315] If the first indication information is used to indicate that the target base station supports PDU set processing, S903, execute the first operation #1.

[0316] If the first indication information is used to indicate that the target base station does not support PDU set processing, S904, determine whether the target base station agrees to the first switching request according to the first feedback message.

[0317] If the first feedback message is used to indicate approval of the first switching request, S905 , perform the first operation # 3 or the first operation # 2.

[0318] If the first feedback message is used to indicate that the first switching request is not approved, S906 , perform the first operation # 3 or the first operation # 4.

[0319] It should be understood that the first operation #1, the first operation #2, the first operation #3 and the first operation #4 can refer to Figure 6 In addition, the execution conditions for triggering these operations can be found in Figure 6 In addition, there is no order of precedence for S902, S903 and S904. Fig. 9 This description is for exemplary purposes only.

[0320] If the source base station determines that the first indication information is not received, the source base station determines that the target base station is an old base station, and S902 determines whether the target base station agrees to the fourth switching request according to the second feedback message.

[0321] If the second feedback message is used to indicate approval of the fourth switching request, S908 , execute the second operation #1 or the second operation #2.

[0322] If the second feedback message is used to indicate that the fourth switching request is not approved, S909 , execute the second operation #3 or the second operation #2.

[0323] It should be understood that the second operation #1, the second operation #2 and the second operation #3 can refer to Figure 7 In addition, the execution conditions for triggering these operations can be found in Figure 7 Description in .

[0324] If passed Figure 6 , Figure 7 or Fig. 9 If the first operation #4 or the second operation #3 in the switching operation is used, the QoS parameters for the PDU set have been removed from the switching request sent by the source base station to the target base station, and the target base station does not know that the service data of the terminal device requires QoS protection based on the PDU set. Therefore, the QoS configuration file currently saved by the target base station does not include the QoS parameters for the PDU set. When the terminal device switching process needs to switch from the current target base station to the next target base station, the switching request at this time will not include the QoS parameters for the PDU set. If the next target base station has the processing capability for the PDU set, at this time, the next target base station will not feedback to the core network that it has the processing capability for the PDU set. Therefore, the core network will not add relevant information about the PDU set to the data packet, resulting in the terminal device being unable to return to the QoS guarantee based on the PDU set.

[0325] Therefore, the embodiments of the present application propose further improvement solutions to the above problems.

[0326] Fig.10 It is a flow chart of another data transmission method provided in an embodiment of the present application.

[0327] S1001, the core network sends a QoS configuration file to the base station where the terminal device is located, and the QoS configuration file includes QoS parameters for PDUset.

[0328] As a possible implementation method, the core network periodically sends a QoS configuration file to the base station where the terminal device is located until a new base station accepts the new QoS configuration file.

[0329] It should be understood that the base station where the terminal device is located may also resend the QoS configuration file to the target base station each time the terminal device switches to the target base station.

[0330] In this way, since the core network side always saves the complete QoS configuration file, which includes the QoS parameters for the PDU set, through this refresh method, even if the QoS configuration file on the base station side loses the PDU set QoS parameters, it can be obtained again from the core network, thereby re-enabling the relevant processing for the PDU set.

[0331] Optionally, before S1001, S1002, after the terminal device switching process occurs, the source base station sends a first notification message to the core network, and the first notification message is used to indicate that the QoS parameters for the PDU set in the QoS configuration file in the source base station have been deleted.

[0332] The execution condition of S1002 may be that the source base station executes the first operation #4 or the second operation #3.

[0333] In this way, not only can the service data based on PDU set QoS guarantee in the terminal device be guaranteed not to be downgraded to PDU-based QoS guarantee due to cell switching, but also the signaling interaction between the core network and the base station can be reduced.

[0334] The above method allows the source base station to learn the processing capability of the target base station for PDU set during the terminal device switching process when the inter-station switching occurs. Before the inter-station switching occurs, the source base station can also learn the processing capability of the surrounding base stations for PDU set.

[0335] Fig.11 It is a flow chart of another data transmission method provided in an embodiment of the present application. Fig.11 The interaction diagram shown in is to illustrate the corresponding method by taking the source base station, the candidate base station B and the core network as the execution subjects of the interaction diagram as an example, but the present application does not limit the execution subjects of the interaction diagram. Fig.11 The source base station in the method may also be a chip, a chip system or a processor that supports the source base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the source base station. Fig.11 The candidate base station B in the description may also be a chip, a chip system or a processor that supports the candidate base station B to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the candidate base station B. Fig.11 The core network in the embodiment may be a chip, a chip system or a processor that supports the core network to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the core network.

[0336] S1101. A source base station sends a first capability query message to a core network. The first capability query message is used to query a processing capability of at least one candidate base station for a PDU set.

[0337] For example, at least one candidate base station may include Fig.11 Candidate base station A and candidate base station B are shown.

[0338] Specifically, the first capability query message includes an identification list of at least one candidate base station.

[0339] S1102: The core network sends second indication information to the source base station, where the second indication information is used to indicate a processing capability of at least one candidate base station for a PDU set.

[0340] Optionally, the core network determines the second indication information.

[0341] It should be understood that the core network has a high probability of mastering the processing capabilities of each base station for PDU set, because as long as any terminal device wants to perform a QoS-guaranteed service based on PDU set (such as XR service), the core network will ask the base station where the terminal device is located to feedback whether it has the processing capability for PDU set when establishing a PDU session or QoS flow for the service. Since this is the capability information of a base station, once the base station has fed back to the core network once, the core network will understand the situation of the base station.

[0342] As a possible implementation manner, if the core network knows the processing capability of at least one candidate base station for the PDU set, then the second indication information is used to indicate whether the at least one candidate base station supports processing the PDU set.

[0343] As a possible implementation method, if the core network has not obtained the processing capability of a certain base station in at least one candidate base station for PDU set, the second indication information is used to indicate that the processing capability of a certain base station for PDU set is unknown or non-existent, and whether other base stations in at least one candidate base station support processing PDU set.

[0344] If the core network has not obtained the processing capability of at least one of the candidate base stations for the PDU set, for example, the core network is unknown to the processing capability of the candidate base station B for the PDU set.

[0345] Optionally, S1103, the core network sends a second capability query message to the candidate base station B, where the second capability query message is used to query the processing capability of the candidate base station B for the PDU set.

[0346] Optionally, S1104, the candidate base station B sends a first capability report to the core network, where the first capability report is used to indicate whether the candidate base station B supports processing PDU set.

[0347] It should be understood that the first capability query message sent by the source base station to the core network may also be further forwarded within the core network. For example, the source base station sends the message to AMF, and AMF forwards the message to SMF. Similarly, the first capability report of candidate base station B may also go through the above forwarding process. Correspondingly, the second capability query message sent by the core network may also be sent by SMF to AMF, and then forwarded by AMF to candidate base station B.

[0348] Optionally, S1107, within the second time period, candidate base station B no longer reports the first capability.

[0349] Specifically, the second duration can be implemented by the first timer. For example, after executing S1104, candidate base station B starts the first timer, and within the second duration, candidate base station B will no longer send the first capability report to the core network. The second duration can be pre-defined by the protocol, or pre-configured to candidate base station B by the core network, or determined by candidate base station B itself.

[0350] The source base station may perform the third operation according to the second indication information.

[0351] Optionally, S1105, during the terminal device switching process, determine the target base station according to the second indication information.

[0352] Specifically, the source base station determines a candidate base station with the processing capability of the PDU set among at least one candidate base station as the target base station in the terminal device switching process according to the processing capability of the at least one candidate base station for the PDU set indicated in the second indication information.

[0353] For example, when selecting a target base station for handover, the source base station can take the acquired base station capability information into consideration. When there are two candidate base stations and the reference signal quality of the terminal device in them is comparable (e.g., the amplitude difference does not exceed 1 dB), the source base station preferentially selects the base station that supports PDU set processing as the target base station for inter-station handover.

[0354] In the above technical solution, by understanding the processing capability of at least one candidate base station for PDU set, the candidate base station with PDU set processing capability is used as the target base station during the inter-station switching process, thereby ensuring the QoS requirements of the terminal device based on PDU set.

[0355] Optionally, S1106, during the switching process of the terminal device, one of the at least one candidate base stations is used as the target base station, the target base station does not support processing PDU set, and the switching request sent to the target base station includes or does not include QoS parameters for PDUset. When the target base station agrees to the switching request, the source base station sends third cache data to the target base station, and the third cache data belongs to a QoS flow with QoS requirements of PDU set, and the third cache data does not include relevant information of PDU set.

[0356] In the above technical solution, even if there is no base station with processing capability for PDU set among the candidate base stations around the source base station, a suitable inter-station switching strategy can be determined in advance, thereby improving the efficiency of data forwarding and avoiding resource waste.

[0357] Fig.11 In the scheme shown, the source base station sends a first capability query message to the core network. Optionally, the source base station can also directly send a capability query message to the surrounding base stations to query whether they have the processing capability for the PDU set. After receiving the capability query message, the surrounding base stations feedback their own capability status to the source base station. Alternatively, the source base station directly obtains the processing capability of the surrounding base stations for the PDU set from the network administrator (such as the operator's network management system).

[0358] For XR services, sometimes the higher the data transmission rate, the better. The transmission rate is the rate at which the application server sends data to the transmission network, that is, the rate at which the application server generates data, not the actual transmission rate of the application data in the network.

[0359] Taking video as an example, when the frame rate is fixed, the higher the transmission rate (or bit rate), the higher the clarity of each frame of video. However, due to the limited bandwidth of the transmission network, a higher transmission rate does not mean a higher transmission rate. When the transmission rate exceeds the available network bandwidth, packet loss may occur, which in turn reduces the user experience.

[0360] For example, suppose that for a video service, when the video definition of 1080p is selected, the transmission rate is 50Mbps, and when the video definition of 4k is selected, the transmission rate is 200Mbps, while the network bandwidth is only 100Mbps. When the definition is selected as 1080p, the network available bandwidth is greater than the video transmission rate, so the network can support the transmission of all video data and users can watch the video normally. If the definition is adjusted to 4k at this time, the network available bandwidth will be less than the video transmission rate, so some video data will inevitably fail to complete the transmission in time. At this time, the video frame may not be decoded or cannot be fully decoded, resulting in black screen, black edges, freezes, etc. in video playback, which seriously degrades the user experience.

[0361] Therefore, the sending rate of XR services should be adjusted according to the network status. For example, when the network is congested, the available bandwidth becomes smaller. At this time, the application should reduce the sending rate of XR services to avoid problems such as service freezes, which affect the user experience.

[0362] In order to achieve the above goals in the 5G system, 3GPP designed the 5G low-latency, low-loss and scalable throughput (L4S) mechanism to enable applications to perceive the status of the 5G transmission network. For the 5G network, the bottleneck of the rate is actually the air interface transmission part, so the congestion state of the 5G network can also be understood as the congestion state of the air interface. Fig.12It is a schematic diagram of the operation mode of the L4S mechanism provided in the embodiment of the present application.

[0363] like Fig.12 As shown in the figure, the operation mode of the L4S mechanism of the 5G system is as follows: in the first mode, the core network decides to add an explicit congestion notification (ECN) mark, or a Congestion Experienced (CE) mark, to the IP header included in the data packet through the 5G base station. The 5G base station receives the data packet from the application server and adds the ECN mark to some data packets according to the network congestion status. In the second mode, the core network decides to add the ECN mark to the IP header included in the data packet. At this time, the core network needs to obtain the congestion information of the air interface from the 5G base station, and determine the data packet to add the ECN mark based on the congestion information. When the terminal device receives a data packet carrying the ECN mark, the application of the terminal device can judge the network congestion status according to the proportion of data packets carrying the ECN mark in the received data packets, and trigger the application server to adjust the sending rate of the data packet. Fig.12 What is shown is the mode of downlink data transmission. The mode of uplink data transmission is similar and is not shown in the figure.

[0364] Currently, 3GPP only requires the base station to send a report request to the core network whether it has the processing capability for PDU set. Different base stations may have different capabilities for the L4S mechanism. The core network cannot decide whether the base station implements the L4S mechanism or how to implement the L4S mechanism based on the processing capability for PDUset. Therefore, how to let the core network know the L4S mechanism of the base station so that the core network can make reasonable decisions on data transmission is an urgent problem to be solved.

[0365] Fig.13 It is a flow chart of another data transmission method provided in an embodiment of the present application. Fig.13 The interaction diagram shown in the figure is to illustrate the corresponding method by taking the first base station, the second base station and the core network as the execution subjects of the interaction diagram as an example, but the present application does not limit the execution subjects of the interaction diagram. Fig.13 The first base station in the method may also be a chip, a chip system or a processor that supports the first base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the first base station. Fig.13 The second base station in the method may also be a chip, a chip system or a processor that supports the second base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the second base station. Fig.13The core network in the embodiment may be a chip, a chip system or a processor that supports the core network to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the core network.

[0366] S1301. The first base station determines third indication information, where the third indication information is used to indicate capability information of the first base station for an L4S mechanism.

[0367] As a possible implementation manner, the third indication information is used to indicate whether the first base station has both the ECN marking capability and the congestion information reporting capability.

[0368] Wherein, when the third indication information is used to indicate that the first base station has capability information for the L4S mechanism, the first base station has ECN marking capability and congestion information reporting capability. When the third indication information is used to indicate that the first base station does not have capability information for the L4S mechanism, the first base station does not have ECN marking capability and congestion information reporting capability.

[0369] For example, one bit is used to represent the third indication information. When the value of the bit is the fifth value, for example, the bit value is "1", the third indication information is used to indicate that the first base station has the ECN marking capability and the congestion information reporting capability. When the value of the bit is the sixth value, for example, the bit value is "0", the third indication information is used to indicate that the first base station does not have the ECN marking capability and the congestion information reporting capability.

[0370] For another example, the third indication information is represented by an enumeration type, and when the enumeration value indicates support, the third indication information is used to indicate that the first base station has the ECN marking capability and the congestion information reporting capability. When the enumeration value indicates non-support, the third indication information is used to indicate that the first base station does not have the ECN marking capability and the congestion information reporting capability.

[0371] As a possible implementation manner, the third indication information is used to indicate whether the first base station has ECN marking capability and congestion information reporting capability respectively.

[0372] In other words, the ECN marking capability and the congestion information reporting capability of the first base station can be indicated respectively through the third indication information.

[0373] For example, two bits are used to represent the third indication information, the first bit is used to indicate whether the first base station supports ECN marking, a value of "1" indicates support, a value of "0" indicates non-support, and the second bit is used to indicate whether the first base station supports congestion information reporting, a value of "1" indicates support, a value of "0" indicates non-support. It should be understood that the specific bit value corresponding to the third indication information here is an exemplary description, and the embodiments of the present application do not limit this.

[0374] It should be understood that in this implementation, the third indication information may be in one message, for example, one message includes 2 bits of the third indication information. Alternatively, the third indication information may be in two messages, for example, two messages respectively include 2 bits of the third indication information, that is, one message includes 1 bit of the third indication information, and the other message includes another bit of the third indication information.

[0375] As a possible implementation manner, the third indication information is used to indicate whether the first base station has an ECN marking capability or a congestion information reporting capability.

[0376] For example, one bit is used to represent the third indication information. When the value of the bit is "1", the third indication information is used to indicate that the first base station has the ECN marking capability. When the value of the bit is "0", the third indication information is used to indicate that the first base station does not have the ECN marking capability. It should be understood that the specific bit value corresponding to the third indication information here is an exemplary description, and the embodiments of the present application are not limited to this.

[0377] For another example, 1 bit is used to represent the third indication information. When the value of the bit is "1", the third indication information is used to indicate that the first base station has the capability to report congestion information. When the value of the bit is "0", the third indication information is used to indicate that the first base station does not have the capability to report congestion information. It should be understood that the specific bit value corresponding to the third indication information here is an exemplary description, and the embodiments of the present application do not limit this.

[0378] S1302: When a trigger condition is met, the first base station sends third indication information to the core network.

[0379] As a possible implementation method, after the trigger condition is met, the first base station sends third indication information to the core network when the first base station has both the ECN marking capability and the congestion information reporting capability in the L4S mechanism, or has the ECN marking capability, or has the congestion information reporting capability.

[0380] At this time, when the first base station does not send the third indication information to the core network, it means that the first base station does not have the ECN marking capability and the congestion information reporting capability in the L4S mechanism, or does not have the ECN marking capability, or does not have the congestion information reporting capability.

[0381] As a possible implementation method, after the trigger condition is met, the first base station sends a third indication information to the core network when the first base station does not have the ECN marking capability and the congestion information reporting capability in the L4S mechanism, or does not have the ECN marking capability, or does not have the congestion information reporting capability.

[0382] At this time, when the first base station does not send the third indication information to the core network, it means that the first base station has both the ECN marking capability and the congestion information reporting capability in the L4S mechanism, or has the ECN marking capability, or has the congestion information reporting capability.

[0383] In the above technical solution, the first base station can promptly notify the core network of its support for L4S, so that the core network can understand the capabilities of the first base station, and thus select an appropriate method when there is a need for L4S, which helps to adjust the service transmission rate in a timely manner and improve user experience. For example, if the first base station only supports ECN marking but not congestion reporting, the core network can instruct the first base station to perform ECN marking. If the first base station only supports congestion reporting but not ECN marking, the core network can instruct the first base station to perform congestion reporting and the core network will be responsible for ECN marking, thereby ensuring that L4S is carried out normally.

[0384] It should be understood that before S1301, there are several possible implementations of the trigger condition.

[0385] S1302a: The core network sends a first capability reporting request to the first base station, where the first capability reporting request is used to request capability information of the first base station for the L4S mechanism.

[0386] As a possible implementation method, the first capability reporting request is used to request the first base station for the ECN marking capability and congestion information reporting capability in the L4S mechanism; or, the first capability reporting request is used to request the ECN marking capability of the first base station, or, the first capability reporting request is used to request the congestion information reporting capability.

[0387] That is, the ECN marking capability and the congestion information reporting capability in the L4S mechanism can be included in one capability reporting request or in two capability reporting requests.

[0388] Specifically, satisfying the trigger condition may be sending third indication information in response to the first capability reporting request.

[0389] It should be understood that the embodiment of the present application does not limit whether the first base station sends the third indication information when it has capability information for the L4S mechanism or sends the third indication information when it does not have capability information for the L4S mechanism after the trigger condition is met.

[0390] S1302b: The core network sends a first start message to the first base station, where the first start message is used to instruct the first base station to mark the ECN and / or start a congestion information reporting operation.

[0391] As a possible implementation, the core network sends a first start message for any QoS flow or DRB. It should be understood that the first start message may be for a specific QoS flow or DRB.

[0392] Specifically, the trigger condition may be satisfied when the first base station has the ECN marking capability and / or the congestion information reporting capability, and sends the third indication information. Alternatively, the trigger condition may be satisfied when the first base station does not have the ECN marking capability and / or the congestion information reporting capability, and sends the third indication information.

[0393] S1302c: The first base station determines that the first data includes a QoS flow for an L4S mechanism.

[0394] As a possible implementation method, when establishing a QoS flow, the core network indicates to the first base station through the first data that the QoS flow supports the L4S function (for example, using a specific QFI), and the first base station determines that it may be necessary to enable the function for the L4S mechanism subsequently.

[0395] Specifically, satisfying the trigger condition may be sending third indication information after receiving the first data.

[0396] It should be understood that the embodiment of the present application does not limit whether the first base station sends the third indication information when it has capability information for the L4S mechanism or sends the third indication information when it does not have capability information for the L4S mechanism after the trigger condition is met.

[0397] S1302d, the first base station receives a second start message from the second base station, where the second start message is used to instruct the first base station to mark the ECN and / or start a congestion information reporting operation.

[0398] As a possible implementation manner, the second startup information instructs the first base station to mark the uplink data flow or downlink data flow of the first QoS flow or the first DRB in the terminal device with ECN and / or start a congestion information reporting operation.

[0399] It should be understood that the first QoS flow is any QoS flow in the terminal device, and the first DRB is any DRB in the terminal device.

[0400] As a possible implementation method, the second startup information is used to indicate that the second base station has marked or is marking ECN and / or performing congestion information reporting operations for the uplink data flow or downlink data flow of the second QoS flow or the second DRB in the terminal device.

[0401] It should be understood that the second QoS flow is any QoS flow in the terminal device, and the second DRB is any DRB in the terminal device.

[0402] As a possible implementation manner, the second startup information is carried in a third switching request, and the third switching request is used to request the terminal device to switch from the second base station to the first base station.

[0403] As a possible implementation, the second startup information is carried in a first response message, the first response message is in response to a terminal device context query request message sent by the first base station to the second base station, and the first response message is used to indicate the context of the terminal device to the first base station. It should be understood that before receiving the first response message, the first base station sends a terminal device context query request message to the second base station, and the context query request message is used to query the context of the terminal device.

[0404] Specifically, satisfying the trigger condition may be sending third indication information in response to the second start message.

[0405] It should be understood that the embodiment of the present application does not limit whether the first base station sends the third indication information when it has capability information for the L4S mechanism or sends the third indication information when it does not have capability information for the L4S mechanism after the trigger condition is met.

[0406] Optionally, the first base station sends a third feedback message to the second base station.

[0407] As a possible implementation, when the type of the third feedback message is a handover request confirmation message and the first base station refuses to accept the QoS flow, the reason for refusing to accept the QoS flow is added to the third feedback message. For example, the first base station does not have the ECN marking capability and congestion information reporting capability in the L4S mechanism, or the first base station does not have the ECN marking capability, or the first base station does not have the congestion information reporting capability.

[0408] As a possible implementation manner, when the type of the third feedback message is a handover preparation failure message and the first base station does not agree to the third handover request, the reason for rejecting the third handover request is added to the third feedback message. For example, the first base station does not have the ECN marking capability and the congestion information reporting capability in the L4S mechanism, or the first base station does not have the ECN marking capability, or the first base station does not have the congestion information reporting capability.

[0409] It should be understood that the embodiment of the present application does not limit the number of times the third indication information is reported when the trigger condition is met. Once the first base station meets the above trigger condition, the third indication information can be sent to the core network.

[0410] Alternatively, the first base station sends the third indication information to the core network only once.

[0411] In this way, once the first base station reports the third indication information once, it will never report the same third indication information again. This is because the capability of the first base station will not change easily. After receiving it once, the core network can understand the capability of the first base station, which can reduce the frequency of information exchange and thus reduce resource consumption.

[0412] Optionally, S1303, the first base station no longer sends the third indication information within the first time period, and the starting time of the first time period is the time when the third indication information is sent each time.

[0413] For example, the first base station starts the second timer each time after sending the third indication information. During the timer running, the first base station no longer sends the third indication information to the core network.

[0414] The first duration may be pre-defined by a protocol, or configured by the core network to the first base station, or determined by the first base station itself.

[0415] In the above technical scheme, by limiting the sending frequency of the third indication information by presetting the duration, the two extreme sending methods of frequently sending the third indication information and sending the third indication information once can be avoided, thereby reducing the frequency of capability reporting and ensuring the timeliness and accuracy of capability reporting.

[0416] Optionally, S1304, the core network determines the behavior of the first base station with respect to the L4S mechanism based on the third indication information.

[0417] Specifically, when the core network decides to enable the L4S function for the terminal device, the core network can instruct the first base station to perform ECN marking for a specific QoS flow or a specific DRB of the terminal device through the fourth indication information. Further, the core network can instruct the first base station to perform ECN marking for the uplink data flow or downlink data flow of the specific QoS flow or DRB.

[0418] Alternatively, if the core network sends fifth indication information to the first base station to instruct the first base station to report congestion information for the uplink data flow or downlink data flow of a specific QoS flow or a specific DRB, the first base station sends sixth indication information to the core network, and the sixth indication information indicates the congestion status of the uplink data flow or downlink data flow of the specific QoS flow or specific DRB of the terminal device, for example, using a percentage to represent the degree of congestion. The core network performs ECN marking for the specific QoS flow or specific DRB of the terminal device based on the congestion information.

[0419] Alternatively, if the core network sends the seventh indication information to the first base station, instructing the first base station to perform ECN marking on the uplink data flow or downlink data flow of a specific QoS flow or a specific DRB of the terminal device and report congestion information, the first base station sends the eighth indication information to the core network, and the eighth indication information is used to indicate the congestion status of the uplink data flow or downlink data flow of the specific QoS flow or a specific DRB of the terminal device, and the first base station performs ECN marking on the uplink data flow or downlink data flow of the specific QoS flow or a specific DRB of the terminal device.

[0420] Optionally, when the first base station is a CU-DU separation scenario, after the CU of the first base station receives the fourth indication information, the fifth indication information or the seventh indication information, it further indicates the DU the fourth indication information, the fifth indication information or the seventh indication information. Messages between the CU and the DU can be transmitted through the F1 interface.

[0421] Specifically, when the first base station is a CU-DU separation scenario, the first base station receives the fourth indication information or the seventh indication information, instructing the first base station to perform ECN marking for the uplink data flow or downlink data flow of a specific QoS flow or DRB, and the DU can send congestion information to the CU. According to the congestion information, the CU performs an ECN marking operation at the packet data convergence protocol (PDCP) layer. When the first base station is a CU-DU separation scenario, the first base station receives the fifth indication information or the seventh indication information, instructing the first base station to report congestion information. The CU of the first base station sends the fifth indication information or the seventh indication information to the DU, and the DU reports the congestion information to the CU. Messages between the CU and the DU can be transmitted through the F1 interface. For example, the DU can carry congestion information in a data packet sent to the CU.

[0422] It should be understood that the DU has a better understanding of the air interface congestion status, so the CU needs the DU to provide auxiliary information to determine which data packets to add the ECN mark to.

[0423] Optionally, when the first base station is a primary base station in a dual connectivity (DC) scenario, after the first base station receives the fourth indication information, the fifth indication information, or the seventh indication information, it further indicates the fourth indication information, the fifth indication information, or the seventh indication information to the secondary base station. The message between the first base station and the secondary base station can be transmitted through the Xn interface. For example, the secondary base station can carry congestion information in a data packet sent to the first base station.

[0424] Specifically, when the first base station is the main base station in the DC scenario, when the first base station receives the fourth indication information or the seventh indication information, instructing the first base station to perform ECN marking for the uplink data flow or downlink data flow of a specific QoS flow or DRB, the secondary base station can send congestion information to the first base station. The first base station performs an ECN marking operation based on the congestion information. When the first base station is the main base station in the DC scenario, the first base station receives the fifth indication information or the seventh indication information, instructing the first base station to report congestion information. The first base station sends the fifth indication information or the seventh indication information to the secondary base station, and the secondary base station reports the congestion information to the first base station. Messages between the first base station and the secondary base station can be transmitted through the Xn interface. For example, the secondary base station can carry congestion information in a data packet sent to the first base station.

[0425] It should be understood that the secondary base station has a better understanding of the congestion status, so the first base station needs the secondary base station to provide congestion information to determine which data packets to add ECN marks to.

[0426] Optionally, the message received by the core network from the first base station, or the message sent by the core network to the first base station, can be transmitted through one or more of AMF, SMF and UPF.

[0427] For example, the third indication information received by the core network from the first base station can first be received by the AMF of the core network, and then sent to the SMF of the core network. The message between the AMF and the base station can be transmitted through the NG interface.

[0428] For another example, the first capability reporting request sent by the core network to the first base station can be sent to the AMF of the core network through the SMF of the core network, and then sent to the first base station through the AMF of the core network. Messages between the AMF and the base station can be transmitted through the NG interface.

[0429] For another example, the fourth indication information, the fifth indication information or the seventh indication information sent by the core network to the first base station can be sent to the AMF of the core network through the SMF of the core network, and then sent to the first base station through the AMF of the core network. Messages between the AMF and the base station can be transmitted through the NG interface.

[0430] For another example, the sixth indication information or the eighth indication information sent by the first base station to the core network can be sent to the UPF of the core network through the NG interface. Specifically, the above message can be carried in the header of the data packet sent by the first base station to the UPF.

[0431] Optionally, when the first base station is a CU-DU separation scenario, before the first base station sends the sixth indication information or the eighth indication information to the core network, the DU may send congestion information to the CU. This is because the DU has a better understanding of the air interface congestion condition. The DU may send congestion information to the CU through the F1 interface. For example, the DU may carry a congestion message in a data packet sent to the CU.

[0432] Optionally, when the first base station is a primary base station in a DC scenario, before the first base station sends the sixth indication information or the eighth indication information to the core network, the secondary base station may send congestion information to the first base station. Messages between the first base station and the secondary base station may be transmitted through an Xn interface. For example, the secondary base station may carry congestion information in a data packet sent to the first base station.

[0433] Above, combined Figures 5 to 13 The data transmission method provided by the embodiment of the present application is described in detail. It can be understood that in order to realize the above functions, it includes hardware structures and / or software modules corresponding to executing each function.

[0434] Those skilled in the art should be aware that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for specific applications, but such implementation should not be considered to be beyond the scope of this application.

[0435] The following, combined Figures 14 to 16 The data transmission device provided in the embodiment of the present application is described in detail. It should be understood that the description of the device embodiment corresponds to the description of the method embodiment, so the contents not described in detail can be referred to the method embodiment above, and some contents will not be repeated for the sake of brevity.

[0436] Fig.14 1 is a schematic diagram of a data transmission device 1400 provided in an embodiment of the present application. The device 1400 may include a processing unit 1420, which is used to perform data processing. The device 1400 may also include a transceiver unit 1410, which may implement corresponding communication functions, and the transceiver unit 1410 may also be referred to as a communication interface or a communication unit or an interface unit. It should be understood that for the operations such as sending and receiving involved in this application, if there is no special explanation, or if it does not conflict with its actual role or internal logic in the relevant description, it can be more generally understood as operations such as output and input, rather than sending and receiving operations directly performed by the radio frequency circuit and the antenna.

[0437] Optionally, the device 1400 may further include a storage unit, which may be used to store instructions and / or data, and the processing unit 1420 may read the instructions and / or data in the storage unit so that the device implements the aforementioned method embodiment.

[0438] The device 1400 can be used to execute the actions performed by the source base station in the above method embodiment. In this case, the device 1400 can be a communication device or a component that can be configured in a communication device. The transceiver unit 1410 is used to execute the transceiver related operations on the communication device side in the above method embodiment, and the processing unit 1420 is used to execute the processing related operations of the source base station in the above method embodiment.

[0439] As a design, the device 1400 is used to perform the above Figure 5 or Figure 6 The actions performed by the source base station during the handover of the terminal device in the method embodiment shown. The execution subject can be a chip, chip system or processor that supports the source base station to implement the corresponding method, or a logic module or software that can implement all or part of the functions of the source base station.

[0440] Specifically, the transceiver unit 1410 is used to send a first switching request, the first switching request including the quality of service QoS parameter of the protocol data unit PDU set of the terminal device, and receive first indication information, the first indication information being used to indicate the processing capability of the target base station for the PDU set during the switching process of the terminal device.

[0441] The processing unit 1420 is configured to perform a switching operation according to the first indication information.

[0442] For matters not described in detail, reference may be made to the above method embodiments.

[0443] As a design, the data transmission device 1400 is used to execute the above Figure 7 The actions performed by the source base station in the method embodiment shown may be performed by a chip, a chip system or a processor that supports the source base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the source base station.

[0444] Specifically, the transceiver unit 1410 is used to send a first capability query message, the first capability query message is used to query the processing capability of at least one candidate base station for a protocol data unit PDU set, and at least one candidate base station will be used for the terminal device switching process. The transceiver unit 1410 is used to receive second indication information, the second indication information is used to indicate the processing capability of at least one candidate base station for the PDU set. The processing unit 1420 is used to perform a switching operation according to the second indication information.

[0445] For matters not described in detail, reference may be made to the above method embodiments.

[0446] As a design, the data transmission device 1400 is used to execute the above Fig.11 The actions performed by the source base station in the method embodiment shown may be performed by a chip, a chip system or a processor that supports the source base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the source base station.

[0447] Specifically, the transceiver unit 1410 is used to send a fourth switching request, wherein the first switching request includes a quality of service QoS parameter of a PDU set. The transceiver unit 1410 is used to receive a second feedback message. The processing unit 1420 is used to determine, based on the first feedback message, that a target base station in a terminal device switching process is an old base station, and the old base station does not have a processing capability for a protocol data unit PDU set. The processing unit 1420 is used to perform a second operation.

[0448] For matters not described in detail, reference may be made to the above method embodiments.

[0449] As a design, the data transmission device 1400 is used to execute the above Fig.13 The actions performed by the first base station in the method embodiment shown may be performed by a chip, a chip system or a processor that supports the first base station to implement the corresponding method, or may be a logic module or software that can implement all or part of the functions of the first base station.

[0450] Specifically, the processing unit 1420 is used to determine the third indication information, where the third indication information is used to indicate the capability information of the first base station for the low latency, low loss and scalable throughput L4S mechanism. The transceiver unit 1410 is used to send the third indication information to the core network when the trigger condition is met.

[0451] For matters not described in detail, reference may be made to the above method embodiments.

[0452] It should be understood that the specific process of each unit executing the above corresponding steps has been described in detail in the above method embodiment, and for the sake of brevity, it will not be repeated here.

[0453] The processing unit 1420 in the above embodiment may be implemented by at least one processor or processor-related circuits. The transceiver unit 1410 may be implemented by a transceiver or a transceiver-related circuit. The storage unit may be implemented by at least one memory.

[0454] Fig.15 It is a schematic structural diagram of a data transmission device 1500 provided in an embodiment of the present application.

[0455] like Fig.15As shown, the embodiment of the present application also provides a data transmission device 1500. The device 1500 includes a processor 1510, the processor 1510 is coupled to a memory 1520, the memory 1520 is used to store computer programs or instructions and / or data, and the processor 1510 is used to execute the computer programs or instructions and / or data stored in the memory 1520, so that the method in the above method embodiment is executed.

[0456] Optionally, the device 1500 includes one or more processors 1510.

[0457] Optional, such as Fig.15 As shown, the device 1500 may further include a memory 1520 .

[0458] Optionally, the memory 1520 included in the device 1500 may be one or more.

[0459] Optionally, the memory 1520 may be integrated with the processor 1510 or provided separately.

[0460] Optional, such as Fig.15 As shown, the device 1500 may further include a transceiver 1530, and the transceiver 1530 is used for receiving and / or sending signals. For example, the processor 1510 is used to control the transceiver 1530 to receive and / or send signals.

[0461] As a solution, the device 1500 is used to implement the operations performed by the source base station, the target base station, the first base station, the second base station or the core network in the above method embodiment.

[0462] For example, the processor 1510 is used to implement processing-related operations performed by the source base station, the target base station, the first base station, the second base station or the core network in the above method embodiments, and the transceiver 1530 is used to implement transceiver-related operations performed by the source base station, the target base station, the first base station, the second base station or the core network in the above method embodiments.

[0463] Fig.16 is a schematic diagram of a chip system 1600 provided in an embodiment of the present application, such as Fig.16As shown. The chip system 1600 (or it may also be referred to as a processing system) includes a logic circuit 1610 and an input / output interface (input / output interface) 1620, the logic circuit is used to couple with the input interface, and transmit data parameters through the input / output interface to execute the method in the above method embodiment. The device installed with the chip system 1600 can implement the method and function of the embodiment of the present application. For example, the logic circuit 1610 can be a processing circuit in the chip system 1600, which realizes the control of the device installed with the chip system 1600, and can also be coupled to a storage unit to call the instructions in the storage unit so that the device can implement the method and function of the embodiment of the present application. The input / output interface 1620 can be an input / output circuit in the chip system 1600, which outputs the information processed by the chip system 1600, or inputs the data or signaling information to be processed into the chip system 1600 for processing.

[0464] As a solution, the chip system 1600 is used to implement the operations performed by the data transmission device (such as the source base station, the target base station, the first base station, the second base station or the core network) in the above method embodiment.

[0465] For example, the logic circuit 1610 is used to implement the processing-related operations performed by the source base station, the target base station, the first base station, the second base station or the core network in the above method embodiments, and the input / output interface 1620 is used to implement the sending and receiving-related operations performed by the source base station, the target base station, the first base station, the second base station or the core network in the above method embodiments.

[0466] An embodiment of the present application also provides a computer-readable storage medium on which computer instructions are stored for implementing the method performed by a data transmission device (such as a source base station, a target base station, a first base station, a second base station or a core network) in the above method embodiment.

[0467] For example, when the computer program is executed by a computer, the computer can implement the method performed by the data transmission device (such as the source base station, the target base station, the first base station, the second base station or the core network) in the above method embodiment.

[0468] An embodiment of the present application also provides a computer program product comprising instructions, which, when executed by a computer, enables the computer to implement the method performed by a data transmission device (such as a source base station, a target base station, a first base station, a second base station or a core network) in the above method embodiment.

[0469] The explanation of the relevant contents and beneficial effects of any of the above-mentioned devices can be referred to the corresponding method embodiments provided above, which will not be repeated here.

[0470] It should be understood that the processor mentioned in the embodiments of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0471] It should also be understood that the memory mentioned in the embodiments of the present application may be a volatile memory and / or a non-volatile memory. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM). For example, RAM can be used as an external cache. By way of example and not limitation, RAM may include the following forms: static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM).

[0472] It should be noted that when the processor is a general-purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, the memory (storage module) can be integrated into the processor.

[0473] It should also be noted that the memory described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0474] Those of ordinary skill in the art will appreciate that the units and steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of protection of this application.

[0475] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0476] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to implement the solution provided by the present application.

[0477] In addition, each functional unit in each embodiment of the present application may be integrated into one unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0478] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loading and executing computer program instructions on a computer, the process or function according to the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices. For example, the computer can be a personal computer, a server, or a network device, etc. The computer instruction can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instruction can be transmitted from a website site, a computer, a server or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server, a data center, etc. that contains one or more available media integrations. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state disk (SSD)). For example, the aforementioned available medium may include, but is not limited to, various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0479] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A data transmission method, characterized in that: The method is applied to a source base station during a terminal device switching process, and includes: Sending a first switching request, where the first switching request includes a quality of service (QoS) parameter of a protocol data unit (PDU) set of the terminal device; Receiving first indication information, where the first indication information is used to indicate a processing capability of a target base station for the PDU set during a handover of the terminal device; Perform a switching operation according to the first indication information.

2. The method according to claim 1, characterized in that The QoS parameters include one or more of a protocol data unit set delay budget PSDB, a protocol data unit set error rate PSER, and a protocol data unit set integrity information PSIHI.

3. The method according to claim 1 or 2, characterized in that: The performing the switching operation according to the first indication information includes: When the first indication information indicates that the target base station has the processing capability of the PDU set, a first cache data packet is sent, where the first cache data packet includes relevant information of the PDU set.

4. The method according to claim 1 or 2, characterized in that: The performing the switching operation according to the first indication information includes: When the first indication information indicates that the target base station does not have the processing capability of the PDU set, a second cached data packet is sent, and the second cached data packet does not include relevant information of the PDU set; or, a new target base station is determined; or, a second switching request is sent to the target base station, and the second switching request does not include QoS parameters of the PDU set.

5. A data transmission method, characterized in that: The method is applied to a source base station where a terminal device is located, and includes: Sending a first capability query message, where the first capability query message is used to query the processing capability of at least one candidate base station for a protocol data unit PDU set, and the at least one candidate base station will be used for the terminal device switching process; receiving second indication information, where the second indication information is used to indicate a processing capability of the at least one candidate base station for the PDU set; Perform a switching operation according to the second indication information.

6. The method according to claim 5, characterized in that The performing the switching operation according to the second indication information includes: The candidate base station indicated by the second indication information and having the processing capability of the PDU set is determined as the target base station in the terminal device switching process.

7. The method according to claim 5, characterized in that The performing the switching operation according to the second indication information includes: When one of the at least one candidate base stations is determined as the target base station in the terminal device switching process, if the target base station does not have the processing capability of the PDU set, third cache data is sent, and the third cache data does not include relevant information of the PDU set.

8. A data transmission method, characterized in that: The method is applied to a first base station, comprising: Determine third indication information, where the third indication information is used to indicate capability information of the first base station for a low latency, low loss and scalable throughput L4S mechanism; When the trigger condition is met, the third indication information is sent to the core network.

9. The method according to claim 8, characterized in that The third indication information is used to indicate whether the first base station has both an explicit congestion notification (ECN) marking capability and a congestion information reporting capability.

10. The method according to claim 8, characterized in that The third indication information is used to indicate whether the first base station has ECN marking capability and congestion information reporting capability respectively.

11. The method according to claim 8, characterized in that The third indication information is used to indicate whether the first base station has an ECN marking capability or a congestion information reporting capability.

12. The method according to any one of claims 8 to 11, characterized in that Before determining the third indication information, the method further includes: receiving a first capability reporting request, where the first capability reporting request is used to request capability information of the first base station for the L4S mechanism; When the trigger condition is met, sending the third indication information includes: In response to the first capability reporting request, the third indication information is sent.

13. The method according to any one of claims 8 to 11, characterized in that Before determining the third indication information, the method further includes: receiving a first start message, where the first start message is used to instruct the first base station to mark an ECN and / or start a congestion information reporting operation; When the trigger condition is met, sending the third indication information includes: When the first base station has or does not have the ECN marking capability and / or the congestion information reporting capability, the third indication information is sent.

14. A data transmission device, characterized in that: The device comprises a transceiver unit and a processing unit: The transceiver unit is used to send a first switching request, where the first switching request includes a quality of service QoS parameter of a protocol data unit PDU set of the terminal device; The transceiver unit is used to receive first indication information, where the first indication information is used to indicate the processing capability of the target base station for the PDU set during the switching process of the terminal device; The processing unit is configured to perform a switching operation according to the first indication information.

15. The device according to claim 14, characterized in that The QoS parameters include one or more of a protocol data unit set delay budget PSDB, a protocol data unit set error rate PSER, and a protocol data unit set integrity information PSIHI.

16. The device according to claim 14 or 15, characterized in that The processing unit is specifically used for: When the first indication information indicates that the target base station has the processing capability of the PDU set, the transceiver unit is controlled to send a first cache data packet, where the first data cache packet includes relevant information of the PDU set.

17. The device according to claim 14 or 15, characterized in that The processing unit is specifically used for: When the first indication information indicates that the target base station does not have the processing capability of the PDU set, controlling the transceiver unit to send a second cache data packet, wherein the second cache data packet does not include relevant information of the PDU set; Alternatively, a new target base station is determined; or alternatively, the transceiver unit is controlled to send a second switching request to the target base station, wherein the second switching request does not include the QoS parameters of the PDU set.

18. A data transmission device, characterized in that: The device comprises a transceiver unit and a processing unit: The transceiver unit is used to send a first capability query message, where the first capability query message is used to query the processing capability of at least one candidate base station for a protocol data unit PDU set, and the at least one candidate base station will be used for the terminal device switching process; The transceiver unit is used to receive second indication information, where the second indication information is used to indicate the processing capability of the at least one candidate base station for the PDU set; The processing unit is configured to perform a switching operation according to the second indication information.

19. The device according to claim 18, characterized in that The processing unit is specifically used for: The candidate base station indicated by the second indication information and having the processing capability of the PDU set is determined as the target base station in the terminal device switching process.

20. The device according to claim 18, characterized in that The processing unit is specifically configured to include: When one of the at least one candidate base stations is determined as the target base station in the terminal device switching process, if the target base station does not have the processing capability of the PDU set, the transceiver unit is controlled to send third cache data, and the third cache data does not include relevant information of the PDU set.

21. A data transmission device, characterized in that: The device comprises a processing unit and a transceiver unit: The processing unit is used to determine third indication information, where the third indication information is used to indicate capability information of the first base station for a low latency, low loss and scalable throughput L4S mechanism; The transceiver unit is used to send the third indication information to the core network when a trigger condition is met.

22. The device according to claim 21, characterized in that The third indication information is used to indicate whether the first base station has both an explicit congestion notification (ECN) marking capability and a congestion information reporting capability.

23. The device according to claim 21, characterized in that The third indication information is used to indicate whether the first base station has ECN marking capability and congestion information reporting capability respectively.

24. The device according to claim 21, characterized in that The third indication information is used to indicate whether the first base station has an ECN marking capability or a congestion information reporting capability.

25. The device according to any one of claims 21 to 24, characterized in that Before the processing unit is used to determine the third indication information, the transceiver unit is further used to: receiving a first capability reporting request, where the first capability reporting request is used to request capability information of the first base station for the L4S mechanism; The transceiver unit is specifically configured to send the third indication information in response to the first capability reporting request.

26. The device according to any one of claims 21 to 24, characterized in that Before the processing unit is used to determine the third indication information, the transceiver unit is further used to: receiving a first start message, where the first start message is used to instruct the first base station to mark an ECN and / or start a congestion information reporting operation; The transceiver unit is specifically configured to send the third indication information when the first base station has or does not have the ECN marking capability and / or the congestion information reporting capability.

27. A data transmission device, characterized in that: The device comprises a processor, the processor is coupled to a memory, the memory is used to store a computer program or instructions, and the processor is used to execute the computer program or instructions in the memory, so that the device performs the method according to any one of claims 1 to 13.

28. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program or instruction, and when the computer program or instruction is executed on a computer, the computer is caused to execute the method according to any one of claims 1 to 13.

29. A chip, characterized in that: The chip is coupled to a memory and is used to read and execute program instructions stored in the memory to implement the method according to any one of claims 1 to 13.

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