A communication method and device

Abstract

The present application relates to the field of communication technology, and discloses a communication method and apparatus. The method includes: a first access network device receives first uplink data from a terminal device, and sends a request message to a core network device, the request message is used to request a path switch of user plane data of the terminal device, and the request message includes first information, and the first information is used to indicate a first PDU session corresponding to the first uplink data. In this way, since the request message sent by the first access network device to the core network device can include the first information, the core network device can refer to the first information to perform admission control on the PDU session of the terminal device, which can improve the rationality of the core network device's admission control on the PDU session.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0002] A protocol data unit (PDU) session is a session between a terminal device and a data network (DN) to provide a PDU connectivity service, wherein the PDU connectivity service may refer to a service for exchanging PDUs between a terminal device and a DN.

[0003] The 5th generation (5G) communication system introduces a new RRC state, namely the RRC inactive state. The terminal device in the RRC inactive state suspends the RRC connection with the access network device and does not need to continuously monitor downlink data, thereby achieving the same power saving effect as the idle state, but the terminal device and the access network device in the RRC inactive state both save the context information of the terminal device.

[0004] However, when a terminal device in an RRC inactive state needs to transmit data, how the core network device performs admission control on the PDU session of the terminal device still requires further research. Summary of the invention

[0005] In view of this, the present application provides a communication method and apparatus for improving the rationality of the admission control of PDU sessions by core network equipment.

[0006] In the first aspect, an embodiment of the present application provides a communication method, which can be applied to a first access network device, or can also be applied to a chip inside the first access network device. Taking the application of the method to the first access network device as an example, in the method, the first access network device receives the first uplink data from the terminal device, and sends a request message to the core network device, the request message is used to request the path switching of the user plane data of the terminal device; the request message includes the first information, and the first information is used to indicate the first PDU session corresponding to the first uplink data.

[0007] By adopting this method, since the request message sent by the first access network device to the core network device can include the first information, the core network device can refer to the first information to perform admission control on the PDU session of the terminal device, which can improve the rationality of the core network device's admission control on the PDU session; for example, the core network device can determine that the first PDU session has uplink data to be transmitted based on the first information, and then can give priority to accepting the first PDU session, effectively avoiding the problem of data failure due to the release of the first PDU session.

[0008] In one possible design, the method also includes: determining a logical channel corresponding to the first uplink data, obtaining indication information from a second access network device, wherein the indication information is used to indicate that the logical channel corresponds to a first protocol data unit PDU session, or the indication information is used to indicate a correspondence between the logical channel and the first PDU session; and then, determining the first PDU session corresponding to the first uplink data based on the logical channel corresponding to the first uplink data and the indication information.

[0009] In one possible design, the method further includes: receiving an RRC connection recovery request from a terminal device; wherein the first uplink data and the RRC connection recovery request are carried in the same message.

[0010] Using this method, since the first uplink data and the RRC connection recovery request are carried in the same message, that is, the first uplink data and the RRC connection recovery request are transmitted simultaneously, that is to say, the terminal device can transmit the first uplink data in an inactive state, thereby ensuring timely transmission of the first uplink data.

[0011] In a possible design, the request message also includes at least one of the following: an identifier QFI of the quality of service QoS flow corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate the second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of the third PDU session; third information, the third information is used to indicate the RRC state of the terminal device.

[0012] By adopting this method, since the request message can include the above-mentioned various possible information, it provides a reference basis for the core network device to perform admission control on PDU sessions from multiple dimensions, which can more effectively improve the rationality of the core network device's admission control on PDU sessions.

[0013] In one possible design, the method further includes: obtaining second information from the terminal device, the second information being determined by the terminal device based on historical data transmission information of the second PDU session; in this case, since the first access network device can directly obtain the second information from the terminal device, the processing burden of the first access network device can be effectively saved. Alternatively, obtaining historical data transmission information of the second PDU session from the second access network device; and determining the second information based on the historical data transmission information of the second PDU session.

[0014] In one possible design, the method further includes: receiving a buffer status report from a terminal device, the buffer status report being used to indicate a remaining amount of uplink data of a first PDU session and / or a remaining amount of uplink data of a third PDU session.

[0015] In one possible design, the method further includes: receiving a response message to the request message from a core network device, the response message including an identifier of an accepted PDU session and / or an identifier of a released PDU session.

[0016] In one possible design, the accepted PDU sessions include the first PDU session; or, the released PDU sessions include the first PDU session.

[0017] In one possible design, the first information includes an identifier of the first PDU session.

[0018] In the second aspect, the embodiment of the present application provides a communication method, which can be applied to a core network device, or can also be applied to a chip inside a core network device. Taking the application of the method to a core network device as an example, in the method, the core network device receives a request message from an access network device, the request message is used to request a path switch of user plane data of a terminal device, and the request message includes first information, and the first information is used to indicate a first PDU session corresponding to the first uplink data; according to the request message, the accepted PDU session and / or the rejected PDU session are determined.

[0019] In a possible design, the request message also includes at least one of the following: a QFI corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate the second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of the third PDU session; third information, the third information is used to indicate the RRC state of the terminal device.

[0020] In one possible design, the method further includes: sending a response message to the request message to the access network device, the response message including an identifier of the accepted PDU session and / or an identifier of a rejected PDU session.

[0021] In one possible design, the accepted PDU session includes the first PDU session; or, the released PDU session includes the first PDU session.

[0022] In one possible design, the first information includes an identifier of the first PDU session.

[0023] It should be noted that the communication method provided in the above-mentioned second aspect corresponds to the first aspect, so the beneficial effects of the relevant technical features of the second aspect can be referred to the description of the first aspect, and the details will not be repeated here.

[0024] In the third aspect, the embodiment of the present application provides a communication method, which can be applied to a first core network device, or can also be applied to a chip inside the first core network device. Taking the application of the method to the first core network device as an example, in the method, the first core network device receives a request message from an access network device, the request message is used to request a path switch of user plane data of a terminal device, the request message includes first information, and the first information is used to indicate a first PDU session corresponding to the first uplink data; according to the request message, the first information is sent to the second core network device; and an indication message is received from the second core network device, the indication message is used to indicate an accepted PDU session and / or a released PDU session.

[0025] Using this method, the first core network device can send the first information to the second core network device, so that the second core network device can refer to the first information to perform admission control on the PDU session of the terminal device, which can improve the rationality of the second core network device's admission control on the PDU session.

[0026] In one possible design, the method also includes: sending at least one of the following items to the second core network device: a QFI corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate a second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of a third PDU session; and third information, the third information is used to indicate the RRC state of the terminal device.

[0027] By adopting this method, since the first core network device can send the above-mentioned various possible information to the second core network device, it provides a reference basis for the second core network device to perform admission control on PDU sessions from multiple dimensions, and can more effectively improve the rationality of the second core network device's admission control on PDU sessions.

[0028] In a fourth aspect, an embodiment of the present application provides a communication method, which can be applied to a second core network device, or can also be applied to a chip inside the second core network device. Taking the application of the method to the second core network device as an example, in the method, the second core network device receives first information from the first core network device, the first information is used to indicate a first PDU session corresponding to the first uplink data; and, according to the first information, sends indication information to the first core network device, the indication information is used to indicate an accepted PDU session and / or a released PDU session.

[0029] In one possible design, the method also includes: receiving at least one of the following from the first core network device: a QFI corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate a second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of a third PDU session; and third information, the third information is used to indicate the RRC state of the terminal device.

[0030] It should be noted that the communication method provided in the fourth aspect corresponds to the third aspect, so the beneficial effects of the relevant technical features of the fourth aspect can be referred to the description of the third aspect, and the details will not be repeated here.

[0031] In a fifth aspect, an embodiment of the present application provides a communication method, which can be applied to an access network device, or can also be applied to a chip inside an access network device. Taking the application of the method to an access network device as an example, in the method, the access network device obtains information, the information is used to indicate the first PDU session corresponding to the uplink data expected to arrive, and sends a request message to the core network device, the request message is used to request the path switching of the user plane data of the terminal device, and the request message includes the information.

[0032] By adopting this method, since the request message sent by the access network device to the core network device can include the above information, the core network device can refer to the above information to perform admission control on the PDU session of the terminal device, which can improve the rationality of the core network device's admission control of the PDU session; for example, the core network device can determine based on the above information that the first PDU session is expected to have uplink data to be transmitted, and then can give priority to accepting the first PDU session, effectively avoiding the problem of data failure due to the release of the first PDU session.

[0033] In one possible design, the request message also includes at least one of the following: a QFI corresponding to the uplink data that is expected to arrive; and QoS parameter information corresponding to the uplink data that is expected to arrive.

[0034] In a sixth aspect, an embodiment of the present application provides a communication method, which can be applied to an access network device, or can also be applied to a chip inside an access network device. Taking the application of the method to an access network device as an example, in the method, the access network device obtains information, which is used to indicate the RRC state of the terminal device; and sends a request message to the core network device, the request message is used to request a path switch of the user plane data of the terminal device, and the request message includes the information.

[0035] By adopting this method, since the request message sent by the access network device to the core network device can include the above information, the core network device can refer to the above information to perform admission control on the PDU session of the terminal device, which can improve the rationality of the core network device's admission control on the PDU session; for example, if the RRC state of the terminal device is inactive, the core network device can reject or release part or all of the PDU sessions of the terminal device; if the RRC state of the terminal device is connected, the core network device should try to accept all PDU sessions of the terminal device to avoid affecting the data transmission of the terminal device.

[0036] In the seventh aspect, an embodiment of the present application provides a communication system, which may include a first access network device and a core network device; wherein the first access network device can be used to execute the method in any possible design or implementation of the first aspect, the fifth aspect or the sixth aspect, and the core network device can be used to execute the method in any possible design or implementation of the second aspect.

[0037] In a possible design, the communication system may further include a second access network device, which is a previous service access network device of the terminal device. Exemplarily, the second access network device may be used to send context information of the terminal device to the first access network device; and / or, the second access network device may be used to send historical data transmission information of the PDU session of the terminal device to the first access network device.

[0038] In the eighth aspect, an embodiment of the present application provides a communication system, which may include a first core network device and a second core network device; wherein the first core network device can be used to execute the method in any possible design or implementation of the third aspect, and the second core network device can be used to execute the method in any possible design or implementation of the fourth aspect.

[0039] In one possible design, the communication system may further include a first access network device, which may be used to execute the method in any possible design or implementation of the first aspect, the fifth aspect, or the sixth aspect.

[0040] In a possible design, the communication system may further include a second access network device, which is a previous service access network device of the terminal device. Exemplarily, the second access network device may be used to send context information of the terminal device to the first access network device; and / or, the second access network device may be used to send historical data transmission information of the PDU session of the terminal device to the first access network device.

[0041] In a ninth aspect, the present application provides a communication device, which may be an access network device (such as a first access network device) or a chip disposed inside the access network device. The communication device has the function of implementing the first aspect, the fifth aspect, or the sixth aspect, for example, the communication device includes a module or unit or means corresponding to the steps involved in the first aspect, the fifth aspect, or the sixth aspect, and the module or unit or means may be implemented by software, or by hardware, or may be implemented by hardware executing the corresponding software.

[0042] In a possible design, the communication device includes a processing unit and a communication unit, wherein the communication unit can be used to send and receive signals to achieve communication between the communication device and other devices, for example, the communication unit is used to receive configuration information from a terminal device; the processing unit can be used to perform some internal operations of the communication device. The functions performed by the processing unit and the communication unit can correspond to the steps involved in the first aspect, the fifth aspect, or the sixth aspect.

[0043] In one possible design, the communication device includes a processor, which can be used to couple with a memory. The memory can store necessary computer programs or instructions for implementing the functions involved in the first aspect, the fifth aspect, or the sixth aspect. The processor can execute the computer program or instructions stored in the memory, and when the computer program or instructions are executed, the communication device implements the method in any possible design or implementation of the first aspect, the fifth aspect, or the sixth aspect.

[0044] In one possible design, the communication device includes a processor and a memory, and the memory can store necessary computer programs or instructions for implementing the functions involved in the first aspect, the fifth aspect, or the sixth aspect. The processor can execute the computer program or instructions stored in the memory, and when the computer program or instructions are executed, the communication device implements the method in any possible design or implementation of the first aspect, the fifth aspect, or the sixth aspect.

[0045] In one possible design, the communication device includes a processor and an interface circuit, wherein the processor is used to communicate with other devices through the interface circuit and execute the method in any possible design or implementation of the first aspect, fifth aspect or sixth aspect above.

[0046] In a tenth aspect, the present application provides a communication device, which may be a core network device (such as a first core network device or a second core network device) or a chip arranged inside a core network device. The communication device has the functions involved in implementing the second, third or fourth aspects above. For example, the communication device includes a module or unit or means corresponding to the steps involved in the second, third or fourth aspects above. The functions or units or means may be implemented by software, or by hardware, or by hardware executing the corresponding software implementation.

[0047] In a possible design, the communication device includes a processing unit and a communication unit, wherein the communication unit can be used to send and receive signals to achieve communication between the communication device and other devices, for example, the communication unit is used to send system information to a terminal device; the processing unit can be used to perform some internal operations of the communication device. The functions performed by the processing unit and the communication unit can correspond to the steps involved in the second aspect, the third aspect, or the fourth aspect.

[0048] In one possible design, the communication device includes a processor, which can be used to couple with a memory. The memory can store necessary computer programs or instructions for implementing the functions involved in the second aspect, the third aspect, or the fourth aspect. The processor can execute the computer program or instructions stored in the memory, and when the computer program or instructions are executed, the communication device implements the method in any possible design or implementation of the second aspect, the third aspect, or the fourth aspect.

[0049] In one possible design, the communication device includes a processor and a memory, and the memory can store necessary computer programs or instructions for implementing the functions involved in the second aspect, the third aspect, or the fourth aspect. The processor can execute the computer program or instructions stored in the memory, and when the computer program or instructions are executed, the communication device implements the method in any possible design or implementation of the second aspect, the third aspect, or the fourth aspect.

[0050] In one possible design, the communication device includes a processor and an interface circuit, wherein the processor is used to communicate with other devices through the interface circuit and execute the method in any possible design or implementation of the second aspect, third aspect or fourth aspect above.

[0051] It can be understood that in the ninth aspect or the tenth aspect above, the processor can be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor, which is implemented by reading the software code stored in the memory. In addition, the above processors can be one or more, and the memory can be one or more. The memory can be integrated with the processor, or the memory can be separately set from the processor. In the specific implementation process, the memory can be integrated with the processor on the same chip, or can be set on different chips respectively. The embodiment of the present application does not limit the type of memory and the setting method of the memory and the processor.

[0052] In the eleventh aspect, the present application provides a computer-readable storage medium, in which computer-readable instructions are stored. When a computer reads and executes the computer-readable instructions, the computer executes a method in any possible design of the first to sixth aspects above.

[0053] In a twelfth aspect, the present application provides a computer program product. When a computer reads and executes the computer program product, the computer executes the method in any possible design of the first to sixth aspects above.

[0054] In the thirteenth aspect, the present application provides a chip, comprising a processor, wherein the processor is coupled to a memory and is used to read and execute a software program stored in the memory to implement a method in any possible design of the first to sixth aspects above.

[0055] These and other aspects of the present application will become more clearly understood in the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 A schematic diagram of a network architecture applicable to an embodiment of the present application;

[0057] Figure 2a An example diagram of the protocol layer structure between the terminal device and the access network device provided in the embodiment of the present application;

[0058] Figure 2b A schematic diagram of a CU-DU separation architecture provided in an embodiment of the present application;

[0059] Figure 2c A schematic diagram of another CU-DU separation architecture provided in an embodiment of the present application;

[0060] Figure 2d A schematic diagram of an air interface protocol stack distribution provided in an embodiment of the present application;

[0061] Figure 3 A schematic diagram of the PDU session establishment process provided in an embodiment of the present application;

[0062] Figure 4 A possible flow chart of the terminal device switching between the RRC connected state and the inactive state provided in the embodiment of the present application;

[0063] Figure 5 A flow chart corresponding to the communication method provided in the embodiment of the present application;

[0064] Figure 6 A possible exemplary block diagram of the device involved in the embodiments of the present application;

[0065] Figure 7 A schematic diagram of the structure of an access network device provided in an embodiment of the present application;

[0066] Figure 8 A schematic diagram of the structure of a core network device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0067] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0068] Figure 1 Schematic diagram of a network architecture applicable to the embodiment of the present application. Figure 1 As shown, the terminal device can access the wireless network to obtain services of the external network (such as a data network (DN)) through the wireless network, or communicate with other devices through the wireless network, such as communicating with other terminal devices. The wireless network includes a radio access network (RAN) and a core network (CN), wherein the RAN can also be called an access network (AN), which is used to access the terminal device to the wireless network, and the CN is used to manage the terminal device and provide a gateway for communicating with the DN.

[0069] The following are Figure 1 The terminal equipment, RAN and CN involved are explained in detail.

[0070] 1. Terminal equipment

[0071] Terminal equipment, also known as user equipment (UE), includes equipment that provides voice and / or data connectivity to users, such as a handheld device with wireless connection function, or a processing device connected to a wireless modem. The terminal device can communicate with the core network via a radio access network (RAN) and exchange voice and / or data with the RAN. The terminal device may include a wireless terminal device, a mobile terminal device, a device-to-device communication (D2D) terminal device, a vehicle to everything (V2X) terminal device, a machine-to-machine / machine-type communication (M2M / MTC) terminal device, an Internet of Things (IoT) terminal device, a subscriber unit, a subscriber station, a mobile station, a remote station, an access point (AP), a remote terminal, an access terminal, a user terminal, a user agent, or a user equipment, etc. For example, it may include a mobile phone (or "cellular" phone), a computer with a mobile terminal device, a portable, pocket-sized, handheld, or a mobile device with a computer built in, etc. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDA), and other devices. It also includes limited devices, such as devices with low power consumption, or devices with limited storage capacity, or devices with limited computing power, etc. For example, it includes information sensing devices such as barcodes, radio frequency identification (RFID), sensors, global positioning systems (GPS), laser scanners, etc.

[0072] In the embodiment of the present application, the device for realizing the function of the terminal device can be a terminal device, or a device that can support the terminal device to realize the function, such as a chip system or a combination device or component that can realize the function of the terminal device, and the device can be installed in the terminal device. In the embodiment of the present application, the chip system can be composed of chips, or it can include chips and other discrete devices. In the technical solution provided in the embodiment of the present application, the technical solution provided in the embodiment of the present application is described by taking the device for realizing the function of the terminal as an example, which is a terminal device.

[0073] 2. RAN

[0074] The RAN may include one or more RAN devices, and the interface between the RAN device and the terminal device may be a Uu interface (or air interface). Of course, in future communications, the names of these interfaces may remain unchanged, or may be replaced by other names, which is not limited in this application.

[0075] RAN equipment is a node or device that connects a terminal device to a wireless network. RAN equipment can also be called access network equipment or base station. Access network equipment includes, but is not limited to: a new generation Node B (gNB), evolved node B (eNB), radio network controller (RNC), node B (NB), base station controller (BSC), base transceiver station (BTS), home evolved node B (HeNB) or home node B (HNB), baseband unit (BBU), transmitting and receiving point (TRP), transmitting point (TP), or mobile switching center in a 5G communication system.

[0076] In the embodiments of the present application, the device for realizing the function of the access network device may be the access network device, or may be a device capable of supporting the access network device to realize the function, such as a chip system or a combination device or component capable of realizing the function of the access network device, and the device may be installed in the access network device. In the technical solution provided in the embodiments of the present application, the technical solution provided in the embodiments of the present application is described by taking the device for realizing the function of the access network device as the access network device as an example.

[0077] (1) Protocol layer structure

[0078] The communication between the RAN device and the terminal device follows a certain protocol layer structure. For example, the control plane protocol layer structure may include a radio resource control (RRC) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, a media access control (MAC) layer and a physical layer; the user plane protocol layer structure may include a PDCP layer, an RLC layer, a MAC layer and a physical layer. In a possible implementation, a service data adaptation protocol (SDAP) layer may also be included above the PDCP layer.

[0079] Taking the data transmission between the access network device and the terminal device as an example, the data transmission needs to pass through the user plane protocol layer, such as the SDAP layer, PDCP layer, RLC layer, MAC layer, and physical layer, wherein the SDAP layer, PDCP layer, RLC layer, MAC layer, and physical layer can also be collectively referred to as the access layer. Exemplarily, data is transmitted between the access network device and the terminal device by establishing at least one data radio bearer (DRB), and each DRB can correspond to a set of functional entities, such as a PDCP layer entity, at least one RLC layer entity corresponding to the PDCP layer entity, at least one MAC layer entity corresponding to at least one RLC layer entity, and at least one physical layer entity corresponding to at least one MAC layer entity. It should be noted that the access network device and the terminal device can also transmit signaling by establishing at least one signaling radio bearer (SRB), and DRB and SRB can be collectively referred to as radio bearers (RB).

[0080] Take the following data transmission as an example: Figure 2a Figure 1 is a schematic diagram of downlink data transmission between layers. Figure 2aThe downward arrow in the figure indicates data transmission, and the upward arrow indicates data reception. After the SDAP layer entity obtains data from the upper layer, it can map the data to the PDCP layer entity of the corresponding DRB according to the data's QoS flow indicator (QFI). The PDCP layer entity can transmit the data to at least one RLC layer entity corresponding to the PDCP layer entity, which is then transmitted by at least one RLC layer entity to the corresponding MAC layer entity. The MAC layer entity then generates a transport block, which is then wirelessly transmitted through the corresponding physical layer entity. Data is encapsulated in each layer accordingly. The data received by a layer from the upper layer of the layer is regarded as the service data unit (SDU) of the layer. After layer encapsulation, it becomes a PDU and is then passed to the next layer. For example, the data received by the PDCP layer entity from the upper layer is called a PDCP SDU, and the data sent by the PDCP layer entity to the lower layer is called a PDCP PDU; the data received by the RLC layer entity from the upper layer is called an RLC SDU, and the data sent by the RLC layer entity to the lower layer is called an RLC PDU. Among them, data can be transmitted between different layers through corresponding channels. For example, data can be transmitted between the RLC layer entity and the MAC layer entity through a logical channel (logical channel, LCH), and data can be transmitted between the MAC layer entity and the physical layer entity through a transport channel (transport channel). Figure 2a It can also be seen that the terminal device also has an application layer and a non-access layer; wherein the application layer can be used to provide services to application programs installed in the terminal device, and the non-access layer can be used to forward user data.

[0081] (2)CU and DU

[0082] In an embodiment of the present application, the RAN device may include one or more centralized units (CU) and one or more distributed units (DU), and multiple DUs may be centrally controlled by one CU. As an example, the interface between the CU and the DU may be referred to as an F1 interface, wherein the control plane (CP) interface may be F1-C and the user plane (UP) interface may be F1-U. The CU and DU may be divided according to the protocol layer of the wireless network: for example Figure 2b As shown, the functions of the PDCP layer and the protocol layers above it are set in the CU, and the functions of the protocol layers below the PDCP layer (such as the RLC layer and the MAC layer, etc.) are set in the DU.

[0083] It can be understood that the above-mentioned division of the processing functions of CU and DU according to the protocol layer is only an example, and it can also be divided in other ways, such as the functions of the protocol layers above the PDCP layer are set in the CU, and the functions of the protocol layers below the PDCP layer are set in the DU. For example, the CU or DU can be divided into functions with more protocol layers, and the CU or DU can also be divided into partial processing functions with protocol layers. In one design, some functions of the RLC layer and the functions of the protocol layers above the RLC layer are set in the CU, and the remaining functions of the RLC layer and the functions of the protocol layers below the RLC layer are set in the DU. In another design, the functions of the CU or DU can also be divided according to the service type or other system requirements, for example, according to the delay, the functions that need to meet the delay requirements for processing time are set in the DU, and the functions that do not need to meet the delay requirements are set in the CU. In another design, the CU may also have one or more functions of the core network. Exemplarily, the CU can be set on the network side for centralized management; the DU can have multiple radio frequency functions, or the radio frequency functions can be set remotely. The embodiments of the present application are not limited to this.

[0084] For example, the functions of a CU may be implemented by one entity, or may be implemented by different entities. Figure 2c As shown, the functions of the CU can be further divided, that is, the control plane and the user plane are separated and implemented through different entities, namely the control plane CU entity (i.e., CU-CP entity) and the user plane CU entity (i.e., CU-UP entity). The CU-CP entity and the CU-UP entity can be coupled with the DU to jointly complete the functions of the RAN device. The interface between the CU-CP entity and the CU-UP entity can be an E1 interface, the interface between the CU-CP entity and the DU can be an F1-C interface, and the interface between the CU-UP entity and the DU can be an F1-U interface. Among them, one DU and one CU-UP can be connected to one CU-CP. Under the control of the same CU-CP, one DU can be connected to multiple CU-UPs, and one CU-UP can be connected to multiple DUs.

[0085] based on Figure 2c , Figure 2d Figure 1 is a schematic diagram of the air interface protocol stack distribution. Figure 2d As shown, for both the user plane and the control plane, the air interface protocol stack can be RLC, MAC, PHY in DU, and PDCP and above protocol layers in CU.

[0086] It should be noted that: Figure 2b to Figure 2dIn the illustrated architecture, the signaling generated by the CU can be sent to the terminal device through the DU, or the signaling generated by the terminal device can be sent to the CU through the DU. The DU may not parse the signaling but directly encapsulate it through the protocol layer and transparently transmit it to the terminal device or CU. In the following embodiments, if the transmission of such signaling between the DU and the terminal device is involved, then the sending or receiving of the signaling by the DU includes this scenario. For example, the signaling of the RRC or PDCP layer will eventually be processed into physical layer signaling and sent to the terminal device, or converted from the received physical layer signaling. Under this architecture, the signaling of the RRC or PDCP layer can also be considered to be sent by the DU, or by the DU and the radio frequency device.

[0087] 3. CN

[0088] CN may include one or more core network devices or core network elements. Taking the 5G communication system as an example, CN may include access and mobility management function (AMF) network element, session management function (SMF) network element, user plane function (UPF) network element, policy control function (PCF) network element, unified data management (UDM) network element, application function (AF) network element, etc.

[0089] The AMF network element is a control plane network element provided by the operator network, which is responsible for the access control and mobility management of terminal devices accessing the operator network, such as mobility status management, allocation of user temporary identity, authentication and authorization of users, etc.

[0090] The SMF network element is a control plane network element provided by the operator network, which is responsible for managing the PDU session of the terminal device. The PDU session is a channel for transmitting PDUs. The terminal device needs to transmit PDUs to and from the DN through the PDU session. The SMF network element is responsible for establishing, maintaining, and deleting the PDU session. The SMF network element includes session management (such as session establishment, modification, and release, including tunnel maintenance between UPF and RAN), selection and control of UPF network elements, service and session continuity (SSC) mode selection, roaming, and other session-related functions.

[0091] The UPF network element is a gateway provided by the operator and is the gateway for the operator network to communicate with the DN. The UPF network element includes user-plane related functions such as data packet routing and transmission, packet detection, quality of service (QoS) processing, legal monitoring, uplink packet detection, and downlink packet storage.

[0092] The PCF network element is a control plane function provided by the operator, which is used to provide PDU session policies to the SMF network element. The policies may include charging-related policies, QoS-related policies, and authorization-related policies.

[0093] The UDM network element is a control plane network element provided by the operator, responsible for storing information such as the subscriber permanent identifier (SUPI) and subscription data of subscribers in the operator's network.

[0094] The AF network element is a functional network element that provides various business services. It can interact with the core network through other network elements, and can interact with the policy management framework to perform policy management.

[0095] In addition, although not shown, the CN may also include other possible network elements, such as a network exposure function (NEF) and a network element unified data repository (UDR) network element.

[0096] In the embodiment of the present application, the device for realizing the function of the core network device may be the core network device, or may be a device capable of supporting the core network device to realize the function, such as a chip system or a combination device or component capable of realizing the function of the core network device, and the device may be installed in the core network device. In the technical solution provided in the embodiment of the present application, the technical solution provided in the embodiment of the present application is described by taking the device for realizing the function of the core network device as the core network device as an example.

[0097] Figure 1 Among them, Npcf, Nudm, Naf, Namf, Nsmf, N1, N2, N3, N4, and N6 are interface serial numbers. The meanings of these interface serial numbers can be found in the definitions in the relevant standard protocols and are not limited here.

[0098] Understandably, Figure 1The 5G communication system is used as an example for illustration, and the solution in the embodiment of the present application can also be applied to other possible communication systems, such as the future sixth generation (the 6th generation, 6G) communication system. The above-mentioned network elements or functions can be network elements in hardware devices, or software functions running on dedicated hardware, or virtualized functions instantiated on a platform (for example, a cloud platform). Optionally, the above-mentioned network elements or functions can be implemented by one device, or by multiple devices together, or can be a functional module in a device, and the embodiments of the present application do not specifically limit this.

[0099] based on Figure 1 The network architecture shown in the figure, the relevant technical features involved in the embodiments of the present application are explained below. It should be noted that these explanations are to make the embodiments of the present application easier to understand and should not be regarded as limiting the scope of protection required by the present application.

[0100] 1. Status of terminal equipment

[0101] The status of a terminal device may include: (1) RRC connected state, i.e., the terminal device has established an RRC connection with the access network device and data transmission can be performed; (2) RRC idle state, i.e., the terminal device has not established an RRC connection with the access network device and the access network device has not stored the context information of the terminal device; if the terminal device needs to enter the RRC connected state from the RRC idle state, it needs to initiate the RRC connection establishment process; (3) RRC inactive state, i.e., the terminal device and the access network device have suspended or hung up the RRC connection, but the network connection corresponding to the terminal device still exists in the core network.

[0102] Among them, the RRC idle state can be simply referred to as the idle state, the RRC inactive state can be simply referred to as the inactive state, and can also be called the third state or the deactivated state, and the RRC connected state can be simply referred to as the connected state.

[0103] 2. PDU Session

[0104] In the above Figure 1 In the illustrated network architecture, data can be transmitted between the terminal device and the DN through a PDU session. Each PDU session can transmit multiple data flows with different QoS requirements, which are called QoS flows. During the establishment or modification of a PDU session, the access network device can configure air interface resources for the QoS flow in the PDU session, and the core network device can establish an N3 tunnel corresponding to the PDU session for the PDU session.

[0105] Take PDU session establishment as an example. Figure 3 For a possible PDU session establishment process diagram, see Figure 3 As shown, the process includes:

[0106] Step 301: The terminal device establishes an RRC connection with access network device 1 and enters a connected state.

[0107] Exemplarily, after the terminal device enters the connected state, it can trigger the core network device to establish a PDU session for the terminal device, and then the following steps 302 to 306 can be executed.

[0108] Step 302, the SMF network element sends a PDU session resource setup request message to access network device 1 through the AMF network element to establish a PDU session for the terminal device.

[0109] Here, the PDU session resource establishment request message includes an identifier of the PDU session to be established (such as PDU session 1), identifiers of multiple QoS flows of the PDU session (QoS flow indicator, QFI), and QoS parameter information of multiple QoS flows. Among them, the QoS parameter information may include a 5G service quality identifier (5G QoS identifier, 5QI), or may include other possible information, such as at least one of the following 5G QoS feature information, which is not specifically limited. 5QI is a scalar used to index to the corresponding 5G QoS feature information. In an example, the 5G QoS feature information may include priority level (priority level), packet delay budget (packet delay budget, PDB), packet error rate (packet error rate, PER), etc.

[0110] Step 303 , the access network device 1 receives the PDU session resource establishment request message and sends an RRC reconfiguration message to the terminal device. The RRC reconfiguration message may include air interface resource configuration information corresponding to multiple QoS flows in the PDU session 1 .

[0111] Here, taking QoS flow 1 in PDU session 1 as an example, access network device 1 can determine the air interface resource configuration information corresponding to QoS flow 1 according to the QoS parameter information of QoS flow 1. Among them, the air interface resource configuration information corresponding to QoS flow 1 may include at least one of the DRB configuration information, PDCP configuration information, RLC configuration information, and logical channel configuration information corresponding to QoS flow 1. In one example, the PDCP configuration information may include the PDCP sequence number (SN) length, the RLC configuration information may include the RLC SN length and the RLC mode, and the logical channel configuration information may include the logical channel identifier.

[0112] Step 304: The terminal device receives the RRC reconfiguration message and performs corresponding configuration according to the RRC reconfiguration message.

[0113] Step 305, access network device 1 sends a PDU session resource establishment response message to the SMF network element through the AMF network element.

[0114] Step 306, the SMF network element can establish the N3 tunnel corresponding to the PDU session (such as the above-mentioned PDU session 1).

[0115] Exemplarily, the SMF network element can allocate an N3 tunnel address on the UPF network element side (referred to as the first N3 tunnel address for ease of description) to the UPF network element, and then send the first N3 tunnel address to the access network device 1 through the AMF network element; accordingly, the access network device 1 receives the first N3 tunnel address, and can allocate an N3 tunnel address on the access network device 1 side (referred to as the second N3 tunnel address), and send the second N3 tunnel address to the SMF network element through the AMF network element, and then send it to the UPF network element by the SMF network element; in addition, the SMF network element can also send the first N3 tunnel address allocated to the UPF network element to the UPF network element; in this way, an N3 tunnel is established between the access network device 1 and the UPF network element, and the data of the PDU session 1 can be transmitted through the N3 tunnel subsequently. Among them, the N3 tunnel address can be the N3 tunnel number.

[0116] 3. State Transition of Terminal Devices

[0117] Figure 4 A possible flow chart of a terminal device entering an inactive state from a connected state is shown in FIG. Figure 4 As shown, the process may include:

[0118] Step 401, access network device 1 sends an RRC connection release (RRC connection release) message to a terminal device in a connected state. The RRC connection release message is used to notify the terminal device to suspend the RRC connection and enter an inactive state.

[0119] Exemplarily, there may be multiple situations in which the access network device 1 sends an RRC connection release message to a terminal device in a connected state. For example, if the access network device 1 does not receive data from the terminal device within a set time period, it may send an RRC connection release message to the terminal device to configure the terminal device to enter an inactive state. Among them, "configuring the terminal device to enter an inactive state" can also be described as "suspending the RRC connection of the terminal device."

[0120] Step 402: The terminal device receives an RRC connection release message, releases the RRC connection, and enters an inactive state.

[0121] Exemplarily, the RRC connection release message may carry a release cause (release cause), for example, the release cause may be set to RRC suspend (RRC suspend) or RRC inactive (RRC inactive). In this way, when the terminal device receives the RRC connection release message and determines that the release cause is RRC suspend or RRC inactive, the RRC connection may be suspended and enter an inactive state. Among them, the release cause may also be understood as indication information indicating that the terminal device enters an inactive state or an idle state.

[0122] The RRC connection release message may also carry a resume ID, which may include information such as the terminal's ID, etc. The terminal's ID may be an inactive radio network temporary identifier (I-RNTI).

[0123] Step 403: The terminal device is in an inactive state and determines that the RRC connection needs to be restored.

[0124] Here, there may be many situations in which the terminal device determines that the RRC connection needs to be restored, such as the terminal device determines that uplink data needs to be transmitted in an inactive state, or the terminal device receives a paging message in an inactive state, or other possible situations, which are not specifically limited.

[0125] Step 404, the terminal device sends an RRC connection resume request (RRC connection resume request) to the access network device 2; accordingly, the access network device 2 receives the RRC connection resume request from the terminal device.

[0126] Exemplarily, the RRC connection resumption request may include a resumption identifier and may also include a resumption reason (resumecause).

[0127] Exemplarily, the terminal device may also send uplink data to the access network device 2 .

[0128] Step 405, after receiving the RRC connection recovery request, access network device 2 sends a retrieve UE context request (retrieve UE context request) to access network device 1, and the retrieve UE context request is used to request to obtain the context information of the terminal device; accordingly, access network device 1 receives the retrieve UE context request from access network device 2.

[0129] Here, access network device 2 can determine the access network device (such as access network device 1) where the context information of the terminal device is located based on the recovery identifier, and then send a UE context retrieval request to access network device 1; wherein the UE context retrieval request may include a recovery identifier.

[0130] Step 406: Access network device 1 sends a retrieve UE context response to access network device 2, where the retrieve UE context response includes context information of the terminal device.

[0131] Exemplarily, the context information of the terminal device may include the access stratum (AS) context of the terminal device, such as the cell identifier of the source primary cell, the physical cell identifier of the source primary cell, the cell radio network temporary identifier (C-RNTI) of the source primary cell, and the robust header compression (ROHC) state. Among them, the source primary cell may refer to the cell of the access network device 1 to which the terminal device accesses before entering the inactive state.

[0132] Optionally, the context information of the terminal device may also include key information, such as at least one of an access layer key, an RRC integrity protection key, a next hop (NH) key, and a next hop chaining counter (NCC).

[0133] Optionally, the context information of the terminal device may also include the identifier of the PDU session of the terminal device, the identifier of the QoS flow in the PDU session, and the air interface resource configuration information corresponding to the QoS flow, and may also include the QoS parameter information corresponding to the QoS flow. In this way, after the access network device 2 receives the context information of the terminal device, it can obtain the correspondence between the PDU session and the logical channel of the terminal device according to the air interface resource configuration information corresponding to the QoS flow in the PDU session. For example, PDU session 1 includes QoS flow 1 and QoS flow 2, QoS flow 1 corresponds to DRB1, DRB1 corresponds to logical channel 1, QoS flow 2 corresponds to DRB2, DRB2 corresponds to logical channel 2, and then it can be determined that PDU session 1 corresponds to logical channel 1 and logical channel 2.

[0134] Step 407: Access network device 2 requests a path switch.

[0135] Here, the purpose of path switching is to change the path of the user plane data of the terminal device (that is, the N3 tunnel corresponding to the PDU session), for example, switching the path of the user plane data from the UPF network element to the access network device 1 to the UPF network element to the access network device 2.

[0136] It should be noted that the access network device 1 and the access network device 2 may be different access network devices. For example, the access network device 2 may be an adjacent access network device of the access network device 1. In this case, the access network device 1 may be referred to as the last serving access network device or the source access network device or the old node, and the access network device 2 may be referred to as the target access network device or the new node. In other possible examples, the access network device 1 and the access network device 2 may also be the same access network device. In this case, the interaction operation between the access network device 1 and the access network device 2 may be omitted.

[0137] Based on the description of the above-mentioned related technical features, the embodiment of the present application will study the relevant implementation of the core network device's admission control of the PDU session of the terminal device when the terminal device in the non-activated state needs to transmit data.

[0138] See above Figure 4 In the process shown, when the terminal device needs to transmit data and the access network device 1 and the access network device 2 are different, the core network device needs to switch the N3 tunnel corresponding to the PDU session of the terminal device. In this case, if the core network device determines that the user plane resources are limited and / or the control plane resources are limited, it may release part or all of the PDU sessions of the terminal device. For example, the access network device 1 and the access network device 2 correspond to different AMF network elements (access network device 1 corresponds to AMF network element 1, and access network device 2 corresponds to AMF network element 2). When the access network device 2 requests path switching, the core network device may release part or all of the PDU sessions of the terminal device due to the limited control plane resources of the AMF network element 2. For another example, the access network device 1 and the access network device 2 correspond to different UPF network elements (access network device 1 corresponds to UPF network element 1, and access network device 2 corresponds to UPF network element 2). When the access network device 2 requests path switching, the core network device may release part or all of the PDU sessions of the terminal device due to the limited user plane resources of the UPF network element 2. Among them, the core network equipment can be an AMF network element or an SMF network element.

[0139] For example, the PDU sessions of the terminal device include PDU session 1, PDU session 2 and PDU session 3, and the terminal device in an inactive state needs to transmit uplink data through PDU session 3. If the access network device 2 requests path switching, the core network device accepts PDU session 1 and PDU session 2, and releases PDU session 3, the terminal device will be unable to transmit uplink data through PDU session 3, thereby affecting the transmission of uplink data.

[0140] Based on this, an embodiment of the present application provides a communication method for improving the rationality of the core network device's admission control of PDU sessions.

[0141] In one possible implementation, the communication method provided by an embodiment of the present application may include: a first access network device sends a request message to a core network device, the request message is used to request path switching of user plane data of a terminal device, and the request message may include auxiliary information; and then the core network device may perform admission control on a PDU session of the terminal device based on the auxiliary information, thereby improving the rationality of the core network device's admission control on the PDU session.

[0142] In an example, the auxiliary information may include at least one of the following: ⑴ first information, the first information is used to indicate a first PDU session corresponding to first uplink data, and the first uplink data is uplink data received by the first access network device from the terminal device; ⑵ QFI corresponding to the first uplink data; ⑶ QoS parameter information corresponding to the first uplink data; ⑷ data volume of the first uplink data; ⑸ the remaining uplink data volume of the first PDU session; ⑹ second information, the second information is used to indicate a second PDU session corresponding to the uplink data that is expected to arrive; ⑺ QFI corresponding to the uplink data that is expected to arrive; ⑻ QoS parameter information corresponding to the uplink data that is expected to arrive; ⑼ the remaining uplink data volume of the third PDU session; ⑽ third information, the third information is used to indicate the RRC state of the terminal device; ⑾ fourth information, the fourth information is used to indicate a fourth PDU session.

[0143] Here, the first PDU session, the second PDU session, the third PDU session and the fourth PDU session involved are explained. Among them, the first PDU session is a PDU session in which uplink data has arrived at the terminal device, and the terminal device has sent part or all of the uplink data that has arrived to the first access network device; the second PDU session is a PDU session in which no uplink data has arrived at the terminal device, but it is expected that uplink data will arrive at the terminal device; the third PDU session is a PDU session in which uplink data has arrived at the terminal device, and the terminal device has not yet sent the uplink data that has arrived to the first access network device; the fourth PDU session is a PDU session in which no uplink data has arrived at the terminal device, and it is expected that no uplink data will arrive.

[0144] Exemplarily, the PDU session of the terminal device may include at least one of a first PDU session, a second PDU session, a third PDU session, and a fourth PDU session.

[0145] It can be understood that the above describes a possible example of auxiliary information. In specific implementations, the above example can also be modified according to actual needs. For example, in the above example, the PDU session of the terminal device is divided into: a first PDU session, a second PDU session, a third PDU session, and a fourth PDU session. In other possible examples, the PDU session of the terminal device can also be divided into: a PDU session with uplink data arriving at the terminal device and a PDU session with no uplink data arriving at the terminal device; in this case, the auxiliary information may include indication information a and / or indication information b, wherein the indication information a is used to indicate the PDU session corresponding to the uplink data arriving at the terminal device (or the PDU session with uplink data arriving at the terminal device, such as the first PDU session and the third PDU session mentioned above), and the indication information b is used to indicate the PDU session with no uplink data arriving at the terminal device (such as the second PDU session and the fourth PDU session mentioned above). Alternatively, the PDU session of the terminal device may be divided into: a PDU session with uplink data arriving at the access network device and a PDU session with no uplink data arriving at the access network device; in this case, the auxiliary information may include indication information c and / or indication information d, the indication information c is used to indicate a PDU session with uplink data arriving at the access network device, and the indication information d is used to indicate a PDU session with no uplink data arriving at the access network device.

[0146] It should be noted that: (1) If the first access network device does not receive the first uplink data from the terminal device before sending a request message to the core network device (that is, the first PDU session is not included in the PDU session of the terminal device), the auxiliary information may not include the above ⑴ to ⑸. If the PDU session of the terminal device does not include the second PDU session, the auxiliary information may not include the above ⑹ to ⑻. If the PDU session of the terminal device does not include the third PDU session, the auxiliary information may not include the above ⑼. If the PDU session of the terminal device does not include the fourth PDU session, the auxiliary information may not include the above ⑾.

[0147] In addition, for the auxiliary information corresponding to each PDU session, the auxiliary information may include one of them, or multiple or all of them. For example, for the first PDU, the auxiliary information may include at least one of the above ⑴ to ⑸, and for another example, for the second PDU, the auxiliary information includes at least one of the above ⑹ to ⑻. Accordingly, the core network device determines the PDU session to be accepted or rejected according to the rules corresponding to the content included in the auxiliary information, which will be described in detail below.

[0148] (2) There may be multiple situations that trigger the first access network device to send a request message to the core network device. For example, when a terminal device in an inactive state needs to transmit data, the first access network device may send a request message to the core network device. In this case, the RRC state of the terminal device indicated by the third information may be an inactive state. For another example, when the terminal device needs to switch from other access network devices to the first access network device, the first access network device sends a request message to the core network device. In this case, the RRC state of the terminal device indicated by the third information may be a connected state.

[0149] Exemplarily, when the RRC state of the terminal device indicated by the third information may be an inactive state, the core network device may reject or release some or all PDU sessions of the terminal device; when the RRC state of the terminal device indicated by the third information may be a connected state, the core network device should try to accept all PDU sessions of the terminal device to reduce the impact on the data transmission of the terminal device. In one example, if the auxiliary information includes the third information, and the RRC state of the terminal device indicated by the third information may be a connected state, the auxiliary information may no longer include the above-mentioned ⑴ to ⑼ and ⑾.

[0150] The following describes in detail the communication method provided in the embodiment of the present application by taking the scenario in which a terminal device in an inactive state needs to perform data transmission as an example.

[0151] Figure 5 This is a flow chart corresponding to the communication method provided in the embodiment of the present application. Figure 5 The first access network device can be the target access network device of the terminal device, the second access network device can be the front service access network device of the terminal device, the first core network device can be an AMF network element, and the second core network device can be an SMF network element.

[0152] like Figure 5 As shown, the method may include:

[0153] Step 501: A terminal device sends first uplink data to a first access network device; correspondingly, the first access network device receives the first uplink data.

[0154] Here, since the context information of the terminal device is saved when the terminal device is in an inactive state, the terminal device can send the first uplink data according to the saved context information.

[0155] In the embodiment of the present application, the terminal device may also send an RRC connection recovery request to the first access network device. The RRC connection recovery request and the first uplink data may be carried in the same message, for example, the message may be message 3 of the four-step random access process or message A of the two-step random access process; or, the first uplink data may be carried in the RRC connection recovery request; or, the RRC connection recovery request and the first uplink data may be carried in different messages, which are not specifically limited.

[0156] In one example, the terminal device may also send to the first access network device at least one of the following: the QFI corresponding to the first uplink data, the QoS parameter information corresponding to the first uplink data, the data volume of the first uplink data, the remaining uplink data volume of the first PDU session, second information (indicating the second PDU session corresponding to the uplink data expected to arrive), the QFI corresponding to the uplink data expected to arrive, the QoS parameter information corresponding to the uplink data expected to arrive, the remaining uplink data volume of the third PDU session, and fourth information (indicating the fourth PDU session).

[0157] There may be multiple ways for the terminal device to send the remaining uplink data volume of the first PDU session to the first access network device. For example, the terminal device may send a cache status report to the first access network device, and the cache status report is used to indicate the remaining uplink data volume of the first PDU session. In one example, the cache status report may include the identifiers of one or more logical channel groups corresponding to the first PDU session and the remaining uplink data volume of each logical channel group. After the first access network device receives the cache status report, it can obtain the remaining uplink data volume of the first PDU session according to the sum of the remaining uplink data volume of one or more logical channel groups corresponding to the first PDU session. Exemplarily, the way in which the terminal device sends the remaining uplink data volume of the third PDU session to the first access network device can refer to the processing.

[0158] It should be noted that the remaining uplink data volume of the first PDU session and the remaining uplink data volume of the third PDU session may be indicated by one buffer status report, or the remaining uplink data volume of the first PDU session and the remaining uplink data volume of the third PDU session may be indicated by different buffer status reports, without specific limitation.

[0159] There may be multiple ways for a terminal device to determine the second PDU session corresponding to the uplink data that is expected to arrive. For example, the terminal device may store the historical data transmission information of one or more PDU sessions of the terminal device. If it is predicted that the second PDU session in one or more PDU sessions will have uplink data arriving based on the historical data transmission information of one or more PDU sessions, the second information may be determined. Furthermore, the QFI corresponding to the uplink data that is expected to arrive and the QoS parameter information corresponding to the uplink data that is expected to arrive may also be determined. Among them, the historical data transmission information of each PDU session may include information such as the amount of data transmitted by each PDU session within a set time period, which is not specifically limited. In addition, the specific way in which the terminal device makes predictions based on the historical data transmission information of one or more PDU sessions may depend on the internal implementation of the terminal device, which is not limited in the embodiments of the present application.

[0160] It should be noted that, in other possible examples, the terminal device may also send at least one of indication information a, indication information b, indication information c, and indication information d to the first access network device.

[0161] Step 502: The first access network device sends a request message to the first core network device, the request message is used to request path switching of user plane data of the terminal device, and the request message may include auxiliary information; accordingly, the first core network device may receive the request message, wherein the request message may be a path switch request message.

[0162] Here, taking the auxiliary information including at least one item of the above ⑴ to ⑾ as an example, some possible implementations of the first access network device obtaining the above ⑴ to ⑾ are explained below.

[0163] (1) With respect to the first information: After receiving the first uplink data, the first access network device may determine the first PDU session corresponding to the first uplink data, thereby obtaining the first information. There may be multiple ways for the first access network device to determine the first PDU session corresponding to the first uplink data. For example, in one possible implementation, the first access network device may determine the logical channel (such as the first logical channel) corresponding to the first uplink data, and obtain first indication information from the second access network device, the first indication information being used to indicate that the first logical channel corresponds to the first PDU session, or the first indication information being used to indicate the correspondence between the first logical channel and the first PDU session, thereby the first access network device may determine the first PDU session corresponding to the first uplink data.

[0164] In the above method, there may be multiple ways for the first access network device to determine the logical channel corresponding to the first uplink data. For example, the first access network device may receive the logical channel identifier corresponding to the first uplink data from the terminal device, and then determine the logical channel corresponding to the first uplink data based on the logical channel identifier corresponding to the first uplink data.

[0165] In the above method, there may be multiple ways for the first access network device to obtain the first indication information from the second access network device. For example, the first access network device may send a UE context retrieval request message to the second access network device, and receive context information sent by the second access network device, wherein the context information includes the first indication information.

[0166] Among them, in one example, the first indication information is used to indicate that the first logical channel corresponds to the first PDU session, which may mean: the first indication information includes the identifier of the first logical channel corresponding to the first PDU session or the identifier of the first PDU session corresponding to the first logical channel. For example, the second access network device can send the first indication information to the first access network device through an XnAP message. In this case, the first access network device can directly obtain the first logical channel corresponding to the first PDU session based on the first indication information. In another example, the first indication information is used to indicate the correspondence between the first logical channel and the first PDU session, which may mean: the first indication information includes the correspondence between the identifier of the first PDU session and the identifier of the first logical channel, and then the first access network device can determine that the first PDU session corresponds to the first logical channel based on the first indication information. For example, the first indication information may include an identifier of the PDU session corresponding to the DRB (for example, an identifier of the first PDU session) and an identifier of the logical channel associated with the DRB (for example, an identifier of the first logical channel); in this case, it can be understood that the second access network device encapsulates the RRC reconfiguration message (including the identifier of the PDU session corresponding to the DRB and the identifier of the logical channel associated with the DRB) and sends it to the first access network device through the Xn interface.

[0167] It should be noted that there may be multiple ways for the first information to indicate the first PDU session corresponding to the first uplink data. In one example, the first information may include an identifier of the first PDU session. In another example, the first information includes identifiers of multiple PDU sessions of the terminal device and indication information corresponding to each PDU session. The indication information corresponding to each PDU session is used to indicate whether the first access network device has received the uplink data of the PDU session. For example, the indication information corresponding to each PDU session may include 1 bit. If the value of the bit is 1, it indicates that the first access network device has received the uplink data of the PDU session. If the value of the bit is 0, it indicates that the first access network device has not received the uplink data of the PDU session.

[0168] (2) Regarding the QFI corresponding to the first uplink data: As described above, the terminal device may send the QFI corresponding to the first uplink data to the first access network device, and then the first access network device may obtain the QFI corresponding to the first uplink data.

[0169] (3) Regarding the QoS parameter information corresponding to the first uplink data: As described above, the terminal device may send the QoS parameter information corresponding to the first uplink data to the first access network device, and then the first access network device may obtain the QoS parameter information corresponding to the first uplink data. Alternatively, the terminal device may not send the QoS parameter information corresponding to the first uplink data to the first access network device. In this case, the first access network device may obtain the QoS parameter information corresponding to the first uplink data based on the QFI or the identifier of the logical channel corresponding to the first uplink data and the context information obtained from the second access network device.

[0170] (4) Regarding the data volume of the first uplink data: As described above, the terminal device may send the data volume of the first uplink data to the first access network device, and then the first access network device may obtain the data volume of the first uplink data. Alternatively, the terminal device may not send the data volume of the first uplink data to the first access network device. In this case, after receiving the first uplink data, the first access network device may determine the data volume of the first uplink data by itself.

[0171] (5) Regarding the remaining uplink data volume of the first PDU session and the remaining uplink data volume of the third PDU session: As described above, the terminal device can send a cache status report to the first access network device, and then the first access network device can obtain the remaining uplink data volume of the first PDU session and the remaining uplink data volume of the third PDU session based on the cache status report.

[0172] (6) Regarding the second information, the QFI corresponding to the uplink data that is expected to arrive, and the QoS parameter information corresponding to the uplink data that is expected to arrive: As described above, the terminal device can send the second information, the QFI corresponding to the uplink data that is expected to arrive, and the QoS parameter information corresponding to the uplink data that is expected to arrive to the first access network device, and then the first access network device can obtain the second information, the QFI corresponding to the uplink data that is expected to arrive, and the QoS parameter information corresponding to the uplink data that is expected to arrive. Alternatively, the terminal device may not send the second information, the QFI corresponding to the uplink data that is expected to arrive, and the QoS parameter information corresponding to the uplink data that is expected to arrive to the first access network device. In this case, the first access network device can obtain the historical data transmission information of one or more PDU sessions of the terminal device from the second access network device. If it is predicted that the second PDU session in the one or more PDU sessions will have uplink data arriving based on the historical data transmission information of the one or more PDU sessions, the second information can be determined, and further, the QFI corresponding to the uplink data that is expected to arrive and the QoS parameter information corresponding to the uplink data that is expected to arrive can also be determined.

[0173] It should be noted that the manner in which the second information indicates the second PDU session corresponding to the uplink data that is expected to arrive can refer to the description of the first information. For example, the second information may include an identifier of the second PDU session, or the second information may include identifiers of multiple PDU sessions of the terminal device and indication information corresponding to each PDU session, and the indication information corresponding to each PDU session is used to indicate whether the PDU session has uplink data that is expected to arrive.

[0174] (7) Regarding the fourth information: As described above, the terminal device may send the fourth information to the first access network device, and the first access network device may obtain the fourth information. Alternatively, the terminal device may not send the fourth information to the first access network device, and the first access network device may determine the first PDU session, the second PDU session and the third PDU session based on other information sent by the terminal device (for example, based on the first information, the second information, and the remaining data volume of the third PDU session), and then determine that the PDU session of the terminal device other than the first PDU session, the second PDU session and the third PDU session is the fourth PDU session, and then obtain the fourth information. There are multiple ways for the fourth information to indicate the fourth PDU session, such as adaptively referring to the description of the first information and the second information mentioned above.

[0175] It should be noted that the above is an example in which the auxiliary information includes at least one of the above ⑴ to ⑾. In other possible examples, if the auxiliary information includes the above indication information a and / or indication information b, then in this case, the terminal device can send indication information a and / or indication information b to the first access network device, and then the first access network device can obtain indication information a and / or indication information b; or, the terminal device may not send indication information a and / or indication information b to the first access network device. In this case, the first access network device can determine the indication information a and / or indication information b based on other possible information sent by the terminal device (such as the first information and the second information). If the auxiliary information includes the above-mentioned indication information c and / or indication information d, then in this case, the terminal device can send indication information c and / or indication information d to the first access network device, and then the first access network device can obtain the indication information c and / or indication information d; or, the terminal device may not send indication information c and / or indication information d to the first access network device. In this case, the first access network device can determine the indication information c and / or indication information d based on other possible information sent by the terminal device (such as the first information).

[0176] Exemplarily, with respect to the above-mentioned indication information a, indication information b, indication information c and indication information d, taking indication information a as an example, the manner in which indication information a indicates that uplink data has arrived at the PDU session of the terminal device can be adaptively referred to the description of the first information.

[0177] Step 503: The first core network device determines the accepted PDU session and / or the released PDU session according to the auxiliary information. The released PDU session may also be described as a rejected PDU session.

[0178] In one example, when the first core network device performs admission control on the PDU session of the terminal device according to the auxiliary information, it can give priority to admitting the PDU session with a higher priority according to the priority of the PDU session. In another example, when the first core network device performs admission control on the PDU session of the terminal device according to the auxiliary information, it can give priority to releasing the PDU session with a lower priority according to the priority of the PDU session.

[0179] For example, the priority rule of the PDU session may include at least one of the following:

[0180] ① The priority of a PDU session with uplink data arriving at the terminal device is higher than the priority of a PDU session without uplink data arriving at the terminal device;

[0181] ② The priority of a PDU session with uplink data arriving at the access network device is higher than the priority of a PDU session without uplink data arriving at the access network device.

[0182] ③ The priority of the first PDU session is greater than the priority of the second PDU session or the priority of the third PDU session or the priority of the fourth PDU session; wherein, the meanings of the first PDU session, the second PDU session, the third PDU session, and the fourth PDU session can refer to the description above;

[0183] ④ The priority of the third PDU session is greater than the priority of the second PDU session or the priority of the fourth PDU session;

[0184] ⑤The priority of the second PDU session is greater than the priority of the fourth PDU session.

[0185] ⑥ For multiple first PDU sessions, for example, PDU session 1 and PDU session 2 are both first PDU sessions, wherein the uplink data 1 received by the first access network device corresponds to PDU session 1, and the uplink data 2 received by the first access network device corresponds to PDU session 2, then the first core network device can judge the delay urgency (or packet loss rate requirement) of uplink data 1 and uplink data 2 according to the QFI and / or QoS parameter information of uplink data 1 and uplink data 2. If the delay urgency of uplink data 1 is greater than the delay urgency of uplink data 2, the priority of PDU session 1 is greater than the priority of PDU session 2. Alternatively, if the data volume of uplink data 1 is greater than the data volume of uplink data 2, the priority of PDU session 1 is greater than the priority of PDU session 2. Alternatively, if the remaining uplink data volume of PDU session 1 is greater than the remaining uplink data volume of PDU session 2, the priority of PDU session 1 is greater than the priority of PDU session 2.

[0186] ⑦ For multiple second PDU sessions, for example, PDU session 1 and PDU session 2 are both second PDU sessions, the uplink data 1 expected to arrive corresponds to PDU session 1, and the uplink data 2 expected to arrive corresponds to PDU session 2, then the first core network device can judge the delay urgency (or packet loss rate requirement) of the uplink data 1 and the uplink data 2 according to the QFI and / or QoS parameter information of the uplink data 1 and the uplink data 2. If the delay urgency of the uplink data 1 is greater than the delay urgency of the uplink data 2, then the priority of PDU session 1 is greater than the priority of PDU session 2.

[0187] ⑧For multiple third PDU sessions, for example, PDU session 1 and PDU session 2 are both third PDU sessions, the uplink data 1 that has arrived at the terminal device corresponds to PDU session 1, and the uplink data 2 that has arrived at the terminal device corresponds to PDU session 2. If the remaining uplink data volume of PDU session 1 (i.e., the data volume of uplink data 1) is greater than the remaining uplink data volume of PDU session 2 (i.e., the data volume of uplink data 2), then the priority of PDU session 1 is greater than the priority of PDU session 2.

[0188] ⑨Multiple fourth PDU sessions can have the same priority.

[0189] It should be noted that: taking the priority rules of multiple first PDU sessions as an example, it can be applicable to multiple first PDU sessions of the same terminal device, or it can also be applicable to multiple first PDU sessions of different terminal devices. In other words, the above-mentioned PDU session 1 and PDU session 2 can be PDU sessions of the same terminal device, or they can also be PDU sessions of different terminal devices. The priority rules of multiple second PDU sessions and the priority rules of multiple third PDU sessions can be adaptively referenced and processed.

[0190] Based on the priority rules described above, several examples are given below to illustrate the admission control of the PDU session by the first core network device.

[0191] For example, the terminal device includes PDU session 1 and PDU session 2, wherein PDU session 1 is the first PDU session and PDU session 2 is the second PDU session. If the first core network device determines that only one PDU session of the terminal device can be accepted, PDU session 1 can be accepted and PDU session 2 can be rejected or released.

[0192] For another example, the terminal device includes PDU session 1 and PDU session 2, wherein PDU session 1 and PDU session 2 are both first PDU sessions, and the remaining uplink data volume of PDU session 1 is greater than the remaining uplink data volume of PDU session 2. If the first core network device determines that only one PDU session of the terminal device can be accepted, PDU session 1 can be accepted, and PDU session 2 can be rejected or released.

[0193] For another example, the terminal device includes PDU session 1, PDU session 2, and PDU session 3, wherein PDU session 1 is the first PDU session, PDU session 2 is the second PDU session, and PDU session 3 is the third PDU session. If the first core network device determines that it can only accept two PDU sessions of the terminal device, it can accept PDU session 1 and PDU session 2, and reject or release PDU session 3.

[0194] To give another example, the terminal device includes PDU session 1 and PDU session 2, wherein PDU session 1 is the second PDU session and PDU session 2 is the third PDU session. If the first core network device determines that it cannot accept the PDU session of the terminal device, it may reject or release PDU session 1 and PDU session 2. There may be many situations in which the first core network device determines that it cannot accept the PDU session of the terminal device, such as the first core network device also needs to accept the PDU sessions of other terminal devices, and the priorities of the PDU sessions of other terminal devices are greater than the priority of the PDU session of the terminal device.

[0195] It should be noted that the above step 503 can also be replaced by step 503': the first core network device sends auxiliary information to the second core network device according to the request message, and then the second core network device can determine the accepted PDU session and / or the released PDU session according to the auxiliary information, and send second indication information to the first core network device, and the second indication information is used to indicate the accepted PDU session and / or the released PDU session. Among them, the second core network device can also determine the accepted PDU session and / or the released PDU session according to the auxiliary information based on the above priority rules, which will not be repeated.

[0196] In one example, the second indication information may include an identifier of an admitted PDU session and / or an identifier of a released PDU session.

[0197] Step 504: The first core network device sends a response message to the request message to the first access network device, wherein the response message includes an identifier of the accepted PDU session and / or an identifier of the released PDU session. Accordingly, the first access network device may receive the response message, wherein the response message may be a path switch request ACK message.

[0198] In one example, the admitted PDU session may include at least one of the first PDU session, the second PDU session, and the third PDU session. In another example, the released PDU session may include at least one of the first PDU session, the second PDU session, and the third PDU session.

[0199] It can be understood that if the first core network device (or the second core network device) accepts all PDU sessions of the terminal device, the response message includes the identifier of the accepted PDU session, and no longer includes the identifier of the rejected PDU session; or does not include the identifier of the PDU session, and all PDU sessions are accepted by default. If the first core network device (or the second core network device) accepts some of the PDU sessions of the terminal device, the response message may include the identifier of the accepted PDU session and / or the identifier of the released PDU session. For example, it may only include the identifier of the accepted PDU session, and the PDU session not included is not accepted by default; or it may only include the identifier of the released PDU session, and the PDU session not included is accepted by default. If the first core network device (or the second core network device) rejects all PDU sessions of the terminal device, the response message includes the identifier of the rejected PDU session, and no longer includes the identifier of the accepted PDU session; or does not include the identifier of the PDU session, and all PDU sessions are rejected by default.

[0200] Exemplarily, after receiving the response message, the first access network device can send the uplink data of the terminal device to the UPF network element through the N3 tunnel corresponding to the accepted PDU session.

[0201] Step 505: The first access network device sends an RRC connection release message to the terminal device.

[0202] Referring to the description in the above step 501, if the terminal device sends an RRC connection recovery request to the first access network device, here, the first access network device can send an RRC connection release message to the terminal device. The RRC connection release message is used to notify the terminal device to continue to stay in the inactive state or enter the idle state. Specifically, the terminal device can be instructed to enter the inactive state or the idle state through the indication information carried by the RRC connection release message. The RRC connection release message can also include at least one of the recovery identifier and the NCC. For example, if the first access network device determines that the amount of uplink data of the terminal device is small and there is no need to restore the RRC connection, it can send an RRC connection release message to the terminal device; or, if the first access network device determines that the terminal device uses preset resources to send uplink data, it can send an RRC connection release message to the terminal device. The preset resources here can be preconfigured grant resources.

[0203] It should be noted that, in other possible examples, the first access network device may also send an RRC connection recovery message to the terminal device to instruct the terminal device to enter a connected state.

[0204] By adopting the above method, since the request message sent by the first access network device to the first core network device can include auxiliary information, the first core network device can refer to the auxiliary information to perform admission control on the PDU session, which can effectively improve the rationality of the first core network device's admission control on the PDU session.

[0205] It should be noted that the process described in the above steps 501 to 505 only illustrates some possible steps. In the specific implementation, other possible steps may also be included. For example, the first access network device may send a terminal device context release (UE context release) message to the second access network device to instruct the second access network device to release the context information of the terminal device.

[0206] In addition, the step numbers of each flowchart described in the embodiments of the present application are only examples of the execution process and do not constitute a limitation on the order of execution of the steps. In the embodiments of the present application, there is no strict execution order between the steps that have no timing dependency relationship with each other. In addition, not all the steps shown in each flowchart are required to be executed. Some steps can be added or deleted based on the actual needs of each flowchart, such as Figure 5 The steps indicated by the dotted lines are all optional steps.

[0207] The embodiments of the present application adopt some messages in the 5G communication system, but in the specific implementation, different messages or message names may be used, and the embodiments of the present application do not limit this.

[0208] The above mainly introduces the solution provided by the embodiment of the present application from the perspective of device interaction. It can be understood that in order to realize the above functions, the access network device or the core network device may include hardware structures and / or software modules corresponding to the execution of each function. It should be easily appreciated by those skilled in the art that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the embodiments of 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 each specific application, but such implementation should not be considered to exceed the scope of this application.

[0209] The embodiment of the present application can divide the access network device or the core network device into functional units according to the above method example. For example, each functional unit can be divided according to each function, or two or more functions can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of software functional units.

[0210] In the case of an integrated unit, Figure 6 A possible exemplary block diagram of the device involved in the embodiments of the present application is shown. Figure 6 As shown, the apparatus 600 may include: a processing unit 602 and a communication unit 603. The processing unit 602 is used to control and manage the actions of the apparatus 600. The communication unit 603 is used to support the communication between the apparatus 600 and other devices. Optionally, the communication unit 603 is also called a transceiver unit, and may include a receiving unit and / or a sending unit, which are respectively used to perform receiving and sending operations. The apparatus 600 may also include a storage unit 601, which is used to store program codes and / or data of the apparatus 600.

[0211] The device 600 may be the first access network device in the above embodiment, or may be a chip set in the first access network device. The processing unit 602 may support the device 600 to perform the actions of the first access network device in each method example above. Alternatively, the processing unit 602 mainly performs the internal actions of the first access network device in the method example, and the communication unit 603 may support the communication between the device 600 and other devices.

[0212] Specifically, in one embodiment, the communication unit 603 is used to: receive first uplink data from a terminal device; and send a request message to a core network device, wherein the request message is used to request a path switching of user plane data of the terminal device; the request message includes first information, and the first information is used to indicate a first PDU session corresponding to the first uplink data.

[0213] In one possible design, the processing unit 602 is used to: determine the logical channel corresponding to the first uplink data; the communication unit 603 is also used to: obtain indication information from the second access network device, the indication information is used to indicate that the logical channel corresponds to the first protocol data unit PDU session, or the indication information is used to indicate the correspondence between the logical channel and the first PDU session; the processing unit 602 is also used to: determine the first PDU session corresponding to the first uplink data based on the logical channel corresponding to the first uplink data and the indication information.

[0214] In a possible design, the communication unit 603 is also used to: receive a radio resource control RRC connection recovery request from the terminal device; wherein the first uplink data and the RRC connection recovery request are carried in the same message.

[0215] In a possible design, the request message also includes at least one of the following: an identifier QFI of the quality of service QoS flow corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate the second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of the third PDU session; third information, the third information is used to indicate the RRC state of the terminal device.

[0216] In one possible design, the communication unit 603 is also used to: obtain second information from the terminal device, where the second information is determined by the terminal device based on historical data transmission information of the second PDU session; or, obtain historical data transmission information of the second PDU session from the second access network device; and determine the second information based on the historical data transmission information of the second PDU session.

[0217] In one possible design, the communication unit 603 is also used to: receive a buffer status report from the terminal device, the buffer status report is used to indicate the remaining uplink data amount of the first PDU session and / or the remaining uplink data amount of the third PDU session.

[0218] In one possible design, the communication unit 603 is also used to: receive a response message to the request message from the core network device, the response message including an identifier of an accepted PDU session and / or an identifier of a released PDU session.

[0219] In one possible design, the accepted PDU sessions include the first PDU session; or, the released PDU sessions include the first PDU session.

[0220] In one possible design, the first information includes an identifier of the first PDU session.

[0221] The device 600 may be the first core network device in the above embodiment, or may be a chip set in the first core network device. The processing unit 602 may support the device 600 to perform the actions of the first core network device in each method example above. Alternatively, the processing unit 602 mainly performs the internal actions of the first core network device in the method example, and the communication unit 603 may support the communication between the device 600 and other devices.

[0222] Specifically, in one embodiment, the communication unit 603 is used to: receive a request message from an access network device, the request message is used to request path switching of user plane data of the terminal device, the request message includes first information, and the first information is used to indicate a first PDU session corresponding to the first uplink data; the processing unit 602 is used to: determine an accepted PDU session and / or a rejected PDU session based on the request message.

[0223] In a possible design, the request message also includes at least one of the following: an identifier QFI of the quality of service QoS flow corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate the second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of the third PDU session; third information, the third information is used to indicate the RRC state of the terminal device.

[0224] In one possible design, the communication unit 603 is further used to: send a response message to the request message to the access network device, and the response message includes an identifier of the accepted PDU session and / or an identifier of the rejected PDU session.

[0225] In one possible design, the accepted PDU session includes the first PDU session; or, the released PDU session includes the first PDU session.

[0226] In one possible design, the first information includes an identifier of the first PDU session.

[0227] In another embodiment, the communication unit 603 is used to: receive a request message from an access network device, the request message being used to request path switching of user plane data of the terminal device, the request message comprising first information, the first information being used to indicate a first PDU session corresponding to the first uplink data; send the first information to a second core network device according to the request message; and receive an indication message from the second core network device, the indication message being used to indicate an accepted PDU session and / or a released PDU session.

[0228] In one possible design, the communication unit 603 is also used to: send at least one of the following items to the second core network device: an identifier QFI of the QoS flow corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate the second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of the third PDU session; third information, the third information is used to indicate the RRC state of the terminal device.

[0229] The device 600 may be the second core network device in the above embodiment, or may be a chip set in the second core network device. The processing unit 602 may support the device 600 to perform the actions of the second core network device in each method example above. Alternatively, the processing unit 602 mainly performs the internal actions of the second core network device in the method example, and the communication unit 603 may support the communication between the device 600 and other devices.

[0230] Specifically, in one embodiment, the communication unit 603 is used to: receive first information from a first core network device, the first information being used to indicate a first PDU session corresponding to first uplink data; and, based on the first information, send indication information to the first core network device, the indication information being used to indicate an accepted PDU session and / or a released PDU session.

[0231] In one possible design, the communication unit 603 is also used to: receive at least one of the following items from the first core network device: an identifier QFI of the quality of service QoS flow corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; the data volume of the first uplink data; the remaining uplink data volume of the first PDU session; second information, the second information is used to indicate the second PDU session corresponding to the uplink data that is expected to arrive; the QFI corresponding to the uplink data that is expected to arrive; the QoS parameter information corresponding to the uplink data that is expected to arrive; the remaining uplink data volume of the third PDU session; third information, the third information is used to indicate the RRC state of the terminal device.

[0232] It should be understood that the division of the units in the above device is only a division of logical functions. In actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. And the units in the device can all be implemented in the form of software calling through processing elements; they can also be all implemented in the form of hardware; some units can also be implemented in the form of software calling through processing elements, and some units can be implemented in the form of hardware. For example, each unit can be a separately established processing element, or it can be integrated in a certain chip of the device. In addition, it can also be stored in the memory in the form of a program, and called and executed by a certain processing element of the device. The function of the unit. In addition, all or part of these units can be integrated together, or they can be implemented independently. The processing element described here can also be a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each unit above can be implemented by an integrated logic circuit of hardware in the processor element or in the form of software calling through a processing element.

[0233] In one example, the unit in any of the above devices may be one or more integrated circuits configured to implement the above method, such as one or more application specific integrated circuits (ASIC), or one or more digital singnal processors (DSP), or one or more field programmable gate arrays (FPGA), or a combination of at least two of these integrated circuit forms. For another example, when the unit in the device can be implemented in the form of a processing element scheduler, the processing element can be a processor, such as a general-purpose central processing unit (CPU), or other processors that can call programs. For another example, these units can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0234] The above unit for receiving is an interface circuit of the device, which is used to receive signals from other devices. For example, when the device is implemented in the form of a chip, the receiving unit is an interface circuit of the chip used to receive signals from other chips or devices. The above unit for sending is an interface circuit of the device, which is used to send signals to other devices. For example, when the device is implemented in the form of a chip, the sending unit is an interface circuit of the chip used to send signals to other chips or devices.

[0235] See also Figure 7 , is a schematic diagram of the structure of an access network device provided in an embodiment of the present application, and the access network device (or base station) can be applied to Figure 1 In the system architecture shown, the functions of the access network device in the above method embodiment are performed. The access network device 70 may include one or more DUs 701 and one or more CUs 702. The DU 701 may include at least one antenna 7011, at least one radio frequency unit 7012, at least one processor 7013 and at least one memory 7014. The DU 701 part is mainly used for receiving and transmitting radio frequency signals and converting radio frequency signals to baseband signals, as well as part of baseband processing. The CU 702 may include at least one processor 7022 and at least one memory 7021.

[0236] The CU 702 part is mainly used for baseband processing, controlling the access network device, etc. The DU 701 and CU 702 can be physically set together or physically separated, that is, a distributed base station. The CU 702 is the control center of the access network device, which can also be called a processing unit, and is mainly used to complete the baseband processing function. For example, the CU 702 can be used to control the access network device to execute the operation process of the access network device in the above method embodiment.

[0237] In addition, optionally, the access network device 70 may include one or more radio frequency units, one or more DUs, and one or more CUs. The DU may include at least one processor 7013 and at least one memory 7014, the radio frequency unit may include at least one antenna 7011 and at least one radio frequency unit 7012, and the CU may include at least one processor 7022 and at least one memory 7021.

[0238] In one example, the CU702 may be composed of one or more boards, and the multiple boards may jointly support a wireless access network (such as a 5G network) with a single access indication, or may respectively support wireless access networks with different access standards (such as an LTE network, a 5G network, or other networks). The memory 7021 and the processor 7022 may serve one or more boards. In other words, a memory and a processor may be separately set on each board. It may also be that multiple boards share the same memory and processor. In addition, necessary circuits may be provided on each board. The DU701 may be composed of one or more boards, and the multiple boards may jointly support a wireless access network (such as a 5G network) with a single access indication, or may respectively support wireless access networks with different access standards (such as an LTE network, a 5G network, or other networks). The memory 7014 and the processor 7013 may serve one or more boards. In other words, a memory and a processor may be separately set on each board. It may also be that multiple boards share the same memory and processor. In addition, necessary circuits may also be provided on each board.

[0239] Figure 7 The access network equipment shown can achieve Figure 5 The illustrated method embodiment involves various processes of the access network device. Figure 7 The operations and / or functions of each module in the access network device shown are respectively for implementing the corresponding processes in the above method embodiments. For details, please refer to the description in the above method embodiments. To avoid repetition, the detailed description is appropriately omitted here.

[0240] refer to Figure 8 , is a structural diagram of a core network device provided in an embodiment of the present application. It can be the SMF network element or AMF network element in the above embodiment, used to implement the operation of the SMF network element or AMF network element in the above embodiment.

[0241] like Figure 8 As shown, the core network device 800 may include a processor 801, a memory 802, and an interface circuit 803. The processor 801 may be used to process the communication protocol and communication data, and to control the communication device. The memory 802 may be used to store programs and data, and the processor 801 may execute the method performed by the AMF network element or the SMF network element in the embodiment of the present application based on the program. The interface circuit 803 may be used for the core network device 800 to communicate with other devices, and the communication may be wired communication or wireless communication. The interface circuit may be, for example, a service-oriented communication interface.

[0242] The above memory 802 may also be externally connected to the core network device 800, in which case the core network device 800 may include an interface circuit 803 and a processor 801. The above interface circuit 803 may also be externally connected to the core network device 800, in which case the core network device 800 may include a memory 802 and a processor 801. When both the interface circuit 803 and the memory 802 are externally connected to the core network device 800, the communication device 800 may include a processor 801.

[0243] Figure 8 The core network equipment shown can achieve Figure 5 The illustrated method embodiment involves various processes of a core network device. Figure 8 The operations and / or functions of each module in the core network device shown are respectively for implementing the corresponding processes in the above method embodiments. For details, please refer to the description in the above method embodiments. To avoid repetition, the detailed description is appropriately omitted here.

[0244] The terms "system" and "network" in the embodiments of the present application can be used interchangeably. "At least one" refers to one or more, and "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B, which can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following (single)" or its similar expression refers to any combination of these items, including any combination of single (single) or plural (single). For example, "at least one of A, B and C" includes A, B, C, AB, AC, BC or ABC. And, unless otherwise specified, the ordinal words such as "first" and "second" mentioned in the embodiments of the present application are used to distinguish multiple objects, and are not used to limit the order, timing, priority or importance of multiple objects.

[0245] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0246] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0247] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0248] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0249] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A communication method, characterized in that: The method is applicable to a first access network device, and the method includes: Receiving first uplink data from a terminal device; A request message is sent to a core network device, wherein the request message is used to request that the path of the user plane data of the terminal device be switched to a user plane network element to the first access network device; the request message includes first information, wherein the first information is used to indicate a first PDU session corresponding to the first uplink data, and the first information is used for admission control of the first PDU session.

2. The method according to claim 1, characterized in that The method further comprises: Determining a logical channel corresponding to the first uplink data; Acquire indication information from the second access network device, where the indication information is used to indicate that the logical channel corresponds to the first protocol data unit PDU session, or the indication information is used to indicate a correspondence between the logical channel and the first PDU session; Determine the first PDU session corresponding to the first uplink data according to the logical channel corresponding to the first uplink data and the indication information.

3. The method according to claim 1, characterized in that The method further comprises: receiving a radio resource control RRC connection recovery request from the terminal device; The first uplink data and the RRC connection recovery request are carried in the same message.

4. The method according to claim 1, characterized in that The request message also includes at least one of the following: An identifier QFI of a quality of service QoS flow corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; The data volume of the first uplink data; The remaining uplink data amount of the first PDU session; second information, where the second information is used to indicate a second PDU session corresponding to the uplink data that is expected to arrive; The QFI corresponding to the uplink data expected to arrive; QoS parameter information corresponding to the uplink data expected to arrive; The remaining uplink data volume of the third PDU session; The third information is used to indicate the RRC state of the terminal device.

5. The method according to claim 4, characterized in that The method further comprises: Acquire the second information from the terminal device, where the second information is determined by the terminal device according to historical data transmission information of the second PDU session; or, Obtain historical data transmission information of the second PDU session from the second access network device; determine the second information based on the historical data transmission information of the second PDU session.

6. The method according to claim 5, characterized in that The method further comprises: Receive a buffer status report from the terminal device, where the buffer status report is used to indicate the remaining uplink data volume of the first PDU session and / or the remaining uplink data volume of the third PDU session.

7. The method according to any one of claims 1 to 6, characterized in that The method further comprises: A response message to the request message is received from the core network device, where the response message includes an identifier of an accepted PDU session and / or an identifier of a released PDU session.

8. The method according to claim 7, characterized in that The accepted PDU session includes the first PDU session; or the released PDU session includes the first PDU session.

9. The method according to any one of claims 1 to 6, characterized in that The first information includes an identifier of the first PDU session.

10. A communication method, characterized in that: The method is applicable to a core network device, and the method includes: Receiving a request message from a first access network device, the request message being used to request that a path of user plane data of a terminal device be switched from a user plane network element to the first access network device, the request message comprising first information, the first information being used to indicate a first PDU session corresponding to the first uplink data, the first information being used for admission control of the first PDU session; According to the request message, an accepted PDU session and / or a rejected PDU session is determined.

11. The method according to claim 10, characterized in that The request message also includes at least one of the following: The QFI corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; The data volume of the first uplink data; The remaining uplink data amount of the first PDU session; second information, where the second information is used to indicate a second PDU session corresponding to the uplink data that is expected to arrive; The QFI corresponding to the uplink data expected to arrive; QoS parameter information corresponding to the uplink data expected to arrive; The remaining uplink data volume of the third PDU session; The third information is used to indicate the RRC state of the terminal device.

12. The method according to claim 10, characterized in that The method further comprises: A response message of the request message is sent to the access network device, wherein the response message includes an identifier of the accepted PDU session and / or an identifier of the rejected PDU session.

13. The method according to claim 12, characterized in that The accepted PDU session includes the first PDU session; or the rejected PDU session includes the first PDU session.

14. The method according to any one of claims 10 to 13, characterized in that The first information includes an identifier of the first PDU session.

15. A communication method, characterized in that: The method is applicable to a first core network device, and the method includes: Receiving a request message from a first access network device, the request message being used to request that a path of user plane data of a terminal device be switched from a user plane network element to the first access network device, the request message comprising first information, the first information being used to indicate a first PDU session corresponding to the first uplink data, the first information being used for admission control of the first PDU session; Sending the first information to the second core network device according to the request message; Receive an indication message from the second core network device in response to the first information, where the indication message is used to indicate an accepted PDU session and / or a released PDU session.

16. The method according to claim 15, characterized in that The method further comprises: Send at least one of the following to the second core network device: The QFI corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; The data volume of the first uplink data; The remaining uplink data amount of the first PDU session; second information, where the second information is used to indicate a second PDU session corresponding to the uplink data that is expected to arrive; The QFI corresponding to the uplink data expected to arrive; QoS parameter information corresponding to the uplink data expected to arrive; The remaining uplink data volume of the third PDU session; The third information is used to indicate the RRC state of the terminal device.

17. A communication method, characterized in that: The method is applicable to a second core network device, and the method includes: Receiving first information from a first core network device, where the first information is used to indicate a first PDU session corresponding to first uplink data, and the first information is used for admission control of the first PDU session; the first information is obtained by the first core network device from a request message from a first access network device, and the request message is used to request that a path of user plane data of a terminal device be switched from a user plane network element to the first access network device; According to the first information, indication information is sent to the first core network device, where the indication information is used to indicate the accepted PDU session and / or the released PDU session.

18. The method according to claim 17, characterized in that The method further comprises: Receive at least one of the following from the first core network device: The QFI corresponding to the first uplink data; QoS parameter information corresponding to the first uplink data; The data volume of the first uplink data; The remaining uplink data amount of the first PDU session; second information, where the second information is used to indicate a second PDU session corresponding to the uplink data that is expected to arrive; The QFI corresponding to the uplink data expected to arrive; QoS parameter information corresponding to the uplink data expected to arrive; The remaining uplink data volume of the third PDU session; The third information is used to indicate the RRC status of the terminal device.

19. A communication system, characterized in that: The communication system includes an access network device and a core network device; wherein the access network device is used to execute the method described in any one of claims 1 to 9, and the core network device is used to execute the method described in any one of claims 10 to 14.

20. A communication system, characterized in that: The communication system includes a first core network device and a second core network device; The first core network device is used to execute the method described in claim 15 or 16, and the second core network device is used to execute the method described in claim 17 or 18.

21. The communication system according to claim 20, characterized in that The communication system further comprises an access network device, and the access network device is used to execute the method according to any one of claims 1 to 9.

22. A communication device, characterized in that: The method comprises means for performing the steps of the method according to any one of claims 1 to 18.

23. A communication device, characterized in that: The system comprises at least one processor and an interface circuit, wherein the at least one processor is used to communicate with other devices through the interface circuit and execute the method according to any one of claims 1 to 18.

24. A communication device, characterized in that: The device comprises a processor, configured to call a program stored in a memory to execute the method according to any one of claims 1 to 18.

25. A computer-readable storage medium, characterized in that: The method comprises a program, and when the program is executed by a processor, the method according to any one of claims 1 to 18 is executed.

26. A computer program product, characterized in that When a computer reads and executes the computer program instructions in the computer program product, the method according to any one of claims 1 to 18 is performed.

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