CN112020104A

CN112020104A - Method, communication device and communication system for background data transmission

Info

Publication number: CN112020104A
Application number: CN201910468636.1A
Authority: CN
Inventors: 丁辉; 时书锋
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-05-31
Filing date: 2019-05-31
Publication date: 2020-12-01
Anticipated expiration: 2039-05-31
Also published as: CN112020104B

Abstract

The application provides a method, a communication device and a communication system for background data transmission, wherein UE triggers PDU session establishment or flow modification in a time window according to the transmission type of the background data transmission in the time window so as to transmit the background data in a first time window, thereby more reasonably using network resources and reducing the waste of the network resources.

Description

Method, communication device and communication system for background data transmission

Technical Field

The present application relates to the field of communications, and more particularly, to a method, a communication apparatus, and a communication system for background data transmission.

Background

Background Data Transfer (BDT) mechanisms are proposed in the prior art. That is, the Application Function (AF) may negotiate a background data transmission policy in advance with the operator network, where the background data transmission policy includes a specific transmission time window (e.g., idle transmission time window), and when the negotiated transmission time window starts, the AF initiates a service request to the network side, and the network side executes a policy decision according to the negotiated background data transmission policy.

The negotiated time window may be provided to the terminal device in a User Routing Selection Policy (URSP) manner, so that the negotiated time window is used for the terminal device to establish a dedicated Protocol Data Unit (PDU) session for transmitting a background data transmission service. Since the opportunity of the AF initiating the service request is not perceived by the terminal device, and the background data transmission mechanism is simultaneously applicable to uplink data transmission and downlink data transmission, in order to avoid that a dedicated PDU session for the background data transmission service is not established yet at the beginning of the downlink data transmission, the terminal device needs to establish the dedicated PDU session at the beginning of the time window, and can release the PDU session only at the end of the time window. That is, the entire time window occupies the corresponding network resources. However, in some scenarios, the terminal device only needs to use a part of the time window to complete the background data transmission, which results in a waste of network resources.

Disclosure of Invention

The application provides a method, a communication device and a communication system for background data transmission, which can use network resources more reasonably and reduce the waste of the network resources.

In a first aspect, a method for background data transmission is provided, including:

first, a terminal device receives a user routing policy. The user routing strategy comprises at least one time window information and at least one transmission indication information, wherein the at least one time window information corresponds to the at least one transmission indication information one to one, the first transmission indication information is used for indicating the transmission type of background data transmission capable of being carried out in a first time window indicated by the first time window information, the first time window corresponds to the first transmission indication information, the first transmission indication information is any one of the at least one transmission indication information, and the first time window information is any one of the at least one time window information.

And then, the terminal equipment triggers a Protocol Data Unit (PDU) session establishment or modification flow in the first time window according to the first transmission indication information so as to transmit the background data in the first time window.

The transmission type in the present application may include uplink transmission, downlink transmission, and uplink transmission and downlink transmission. That is, the background data transmission that can be performed in a time window may be uplink transmission, may also be downlink transmission, and may also include both uplink transmission and downlink transmission.

According to the method provided by the application, the first policy control function network element can provide the transmission indication information corresponding to each time window information to the terminal equipment when providing the user routing policy to the terminal equipment, so that the terminal equipment can trigger the PDU session establishment or the PDU session modification flow based on the transmission type of the background data transmission capable of being performed in the time window indicated by each time window information, thereby more reasonably using the network resources and reducing the waste of the network resources.

For example, in some implementations, the triggering, by the terminal device, a PDU session establishment or modification procedure within the first time window according to the first transmission indication information includes:

if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is uplink transmission, triggering PDU session establishment or a PDU session modification process when the terminal device determines that the background data transmission needs to be initiated in the first time window.

That is, the terminal device triggers the PDU session establishment or modification procedure only at the time when the PDU session establishment or modification procedure needs to be triggered within the first time window, and does not need to trigger the PDU session establishment or modification procedure at the beginning of the time window, thereby avoiding the network resource overhead caused by maintaining the session context and saving the network resources to a certain extent.

In another implementation manner, the triggering, by the terminal device, a PDU session establishment or modification procedure within a first time window according to the first transmission indication information includes:

if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is downlink transmission, or downlink transmission and uplink transmission, the terminal device triggers PDU session establishment or a PDU session modification process when the first time window starts.

Because the opportunity of the application function network element for initiating the service request is not perceived by the terminal device, when the background data transmission required in the first time window is downlink transmission or downlink transmission and uplink transmission, the PDU session establishment or the PDU session modification process is triggered at the beginning of the first time window, so that the problem that the special PDU session for the background data transmission service is not established at the beginning of the downlink data transmission and the background data transmission service cannot be normally transmitted can be avoided.

In some implementations, the user routing policy further includes at least one Network Area Information (NAI), the at least one NAI corresponds to the at least one time window information and the at least one transmission indication information one to one, and a first network area indicated by a first network area information of the at least one NAI corresponds to the first time window and the first transmission indication information;

and the terminal equipment triggers a PDU session establishment or modification process in the first time window according to the first transmission indication information, and the process comprises the following steps:

and under the condition that the terminal equipment is positioned in the first network area, the terminal equipment triggers PDU session establishment or flow modification in the first time window according to the first transmission indication information.

The scheme can well inherit the prior art, namely the PDU session establishment or the modification process is triggered when the terminal equipment is positioned in the network area.

In some implementations, the method can further include: and the terminal equipment sends first feedback information, wherein the feedback information is used for indicating the terminal equipment to successfully receive the user routing strategy.

Based on the scheme, when the terminal device does not successfully receive the user routing strategy, the user routing strategy can be retransmitted.

In a second aspect, a method for background data transmission is provided, including:

first, a terminal device receives a user routing policy. The user routing strategy comprises first time window information and first transmission indication information, wherein the first transmission indication information is used for indicating the transmission type of background data transmission which can be carried out in the first time window indicated by the first time window information.

According to the system provided by the application, the first policy control function network element can provide the first transmission indication information corresponding to the first time window information to the terminal equipment when providing the user routing policy to the terminal equipment, so that the terminal equipment can trigger the PDU session establishment or modification flow based on the transmission type of the background data transmission capable of being performed in the first time window indicated by the first time window information, thereby more reasonably using network resources and reducing the waste of the network resources.

In some implementations, the user routing policy further includes first network area information, a first network area indicated by the first network area information corresponding to the first time window and the first transmission indication information;

The method of the second aspect may be implemented in a specific manner by referring to the method of the first aspect, and the second aspect will not be described herein.

In a third aspect, a method for background data transmission is provided, including:

a second policy control function network element receives a policy association creation request message, where the policy association creation request message includes a Data Network Name (DNN) and a user permanent identifier (SUPI); a second policy control function network element transmitting a data query request message including the DNN and the SUPI to a Unified Data Repository (UDR), the data query request message requesting a background data transfer policy; and the second policy control function network element receives the background data transmission policy corresponding to both the DNN and the SUPI sent by the UDR.

As will be understood by those skilled in the art, in the present application, the policy association creation request message is used to request Session management policy information, where the Session management policy indicates a control policy provided by the second policy control function network element to the Session management function network element for a specific Session or a specific data stream in the Session, for example, an Aggregated Maximum Bit Rate (AMBR) parameter of a Session (Session) for controlling a bandwidth of the Session, an event trigger for subscribing to a specific event in the Session, or a policy and charging control rule executed for a specific traffic stream in the Session, etc. The DNN represents the specific data network name corresponding to a PDU session on the terminal device, determining the manner or access technology by which the terminal device accesses the network. The SUPI represents a user permanent identity as a globally unique identity for a subscriber.

According to the method provided by the present application, the second policy control function network element may obtain the background data transfer policy from the UDR based on DNN and SUPI. Compared with the method that the application function network element sends the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user (or called terminal equipment), the method can save signaling overhead because the application function network element does not need to send the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user any more.

In a possible implementation manner, the policy association creation request message further includes single network slice selection assistance information (S-NSSAI). And the data query request message further includes the S-NSSAI, the S-NSSAI corresponding to the background data transmission policy.

Wherein the S-NSSAI represents single network slice selection assistance information, consisting of slice type and slice description information, for identifying one or more slice instances in a particular slice type in an operator network.

Based on the scheme, the second policy control function network element may further obtain the background data transmission policy from the UDR in combination with the S-NSSAI.

In a fourth aspect, another method for background data transmission is provided, comprising:

a second policy control function network element receiving a policy association update request message, the policy association update request message including Service Data Flow (SDF) description information and SUPI; a second policy control function network element transmitting a data query request message to the UDR, the data query request message including the service data flow description information, the SUPI, and a data network name DNN, the data query request for requesting a background data transfer policy; and the second policy control function network element receives a background data transmission policy sent by the UDR, wherein the background data transmission policy corresponds to the service data flow description information, the SUPI and the DNN.

Those skilled in the art will understand that the service data flow description information is used to describe the traffic flow for the terminal device initiated PDU session modification corresponding to the policy association update request message. The policy association update request message is used to request for updated policy rule information, and the policy association update request message may carry an event subscribed by the second policy control function network element, such as a resource modification request event initiated by the terminal device. The DNN is obtained by the second policy control function network element when the PDU session is established, represents a specific data network name corresponding to the PDU session, and determines a mode or an access technology by which the terminal device accesses the network. The SUPI represents a user permanent identity as a globally unique identity for a subscriber.

According to the method provided by the present application, the second policy control function network element may obtain the background data transmission policy from the UDR based on the service flow description information and the DNN. Compared with the method that the application function network element sends the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user (or called terminal equipment), the method can save signaling overhead because the application function network element does not need to send the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user any more.

In one possible implementation, the data query request message further includes an S-NSSAI, and the S-NSSAI corresponds to the background data transmission policy.

The S-NSSAI is acquired by the second policy control function network element when the PDU session is established, represents single network slice selection auxiliary information, is composed of a slice type and slice description information, and is used to identify one or more slice instances in a specific slice type in the operator network.

In a fifth aspect, a method for background data transmission is provided, including: the UDR receives a data query request message sent by a second policy control function network element, wherein the data query request message comprises DNN and SUPI, and the data query request is used for requesting a background data transmission policy; and the UDR sends a background data transmission strategy to a second strategy control function network element according to the data query request message, wherein the background data transmission strategy corresponds to the DNN and the SUPI.

Those skilled in the art will appreciate that the DNN represents the specific data network name for a PDU session on the terminal device, determining the manner or access technology by which the terminal device accesses the network. The SUPI represents a user permanent identity as a globally unique identity for a subscriber.

In a possible implementation manner, the data query request message further includes service data flow description information, and the background data transmission policy further corresponds to the service data flow description information.

It should be understood that the service data flow description information is used to describe the traffic flow for which the terminal device initiated PDU session modification corresponds to the policy association update request message.

Based on the scheme, the second policy control function network element may further obtain the background data transmission policy from the UDR in combination with the service data flow description information.

A sixth aspect provides a communication system, including a terminal device and a first policy control function network element;

a first policy control function network element, configured to obtain at least one time window information and at least one transmission indication information, and send a user routing policy to a terminal device, where the user routing policy includes the at least one time window information and the at least one transmission indication information, the at least one time window information corresponds to the at least one transmission indication information one to one, the first transmission indication information is used to indicate a transmission type of background data transmission that can be performed in a first time window indicated by the first time window information, the first time window corresponds to the first transmission indication information, the first transmission indication information is any one of the at least one transmission indication information, and the first time window information is any one of the at least one time window information;

and the terminal equipment is used for receiving the user routing strategy and triggering a Protocol Data Unit (PDU) session establishment or modification flow in the first time window according to the first transmission indication information so as to transmit background data in the first time window.

According to the system provided by the application, the first policy control function network element can provide the transmission indication information corresponding to each time window information to the terminal equipment when providing the user routing policy to the terminal equipment, so that the terminal equipment can trigger the PDU session establishment or the PDU session modification flow based on the transmission type of the background data transmission capable of being performed in the time window indicated by each time window information, thereby more reasonably using the network resources and reducing the waste of the network resources.

In a possible implementation manner, the terminal device is configured to trigger a PDU session establishment or modification procedure within the first time window according to the first transmission indication information, and includes: if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is uplink transmission, the terminal device is configured to trigger PDU session establishment or a PDU session modification procedure when it is determined that the background data transmission needs to be initiated in the first time window.

In a possible implementation manner, the terminal device is configured to trigger a PDU session establishment or modification procedure within the first time window according to the first transmission indication information, and includes: and if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is downlink transmission or downlink transmission and uplink transmission, the terminal device is configured to trigger PDU session establishment or a PDU session modification process when the first time window starts.

In one possible implementation, the system further comprises a first unified data repository UDR.

The first UDR is configured to send the at least one time window information and the at least one transmission indication information to the first policy control function network element;

and the first policy control function network element is configured to acquire at least one time window information and at least one transmission indication information, and includes:

and the first policy control function network element is configured to receive the at least one time window information and the at least one transmission indication information sent by the first UDR.

In a possible implementation manner, the system further includes an application function network element.

The application function network element is configured to send a background data transmission policy negotiation request message to the first policy control function network element, where the background data transmission policy negotiation request message includes the at least one time window information and the at least one transmission indication information;

and, the first policy control function, the network element, configured to obtain at least one time window information and at least one transmission indication information, includes:

the first policy control function network element is configured to acquire the at least one time window information and the at least one transmission indication information from the background data transmission policy negotiation request message.

The two manners are two possible manners in which the first policy control function obtains the at least one time window information and the at least one transmission indication information.

In a possible implementation manner, the user routing policy further includes at least one network area information, the at least one network area information corresponds to the at least one time window information and the at least one transmission indication information one to one, and a first network area indicated by a first network area information in the at least one network area information corresponds to the first time window and the first transmission indication information;

and the terminal device, configured to establish or modify a protocol data unit, PDU, session within the first time window according to the first transmission indication information, including:

and the terminal device is configured to trigger a PDU session establishment or a PDU session modification procedure within the first time window according to the first transmission indication information when the terminal device is located in the first network region.

In a possible implementation manner, the system further includes a session management function network element, a second policy control function network element, and a second unified data repository UDR;

and the terminal device is configured to trigger a PDU session establishment procedure within the first time window according to the first transmission indication information, and includes:

the terminal device is configured to send a PDU session establishment request message to the session management function network element according to the first indication information, where the PDU session establishment request message includes a data network name DNN and a user permanent identity SUPI;

the session management function network element is configured to receive the PDU session establishment request message, and send a policy association establishment request message to the second policy control function network element, where the policy association establishment request message includes the DNN and the SUPI;

the second policy control function network element, configured to receive the policy association creation request message and send a data query request message to the second UDR, where the data query request message includes the DNN and the SUPI, and the data query request message is used to request a background data transfer policy, where the background data transfer policy corresponds to the DNN and the SUPI;

the second UDR is configured to receive the data query request message, and send the background data transmission policy to the second policy control function network element according to the data query request message;

and the second policy control function network element is further configured to receive the background data transmission policy sent by the second UDR.

According to the system provided by the present application, the second policy control function network element may obtain the background data transfer policy from the UDR based on SUPI and DNN. Compared with the method that the application function network element sends the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user (or called terminal equipment), the method can save signaling overhead because the application function network element does not need to send the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user any more.

In one possible implementation, the PDU session setup request message further includes single network slice selection assistance information S-NSSAI, the policy association creation request message further includes the S-NSSAI, and the data query request message further includes the S-NSSAI, where the S-NSSAI corresponds to the background data transmission policy.

and the terminal device is configured to trigger a PDU session modification procedure within the first time window according to the first transmission indication information, and includes:

the terminal device is configured to send a PDU session modification request message to the session management function network element according to the first transmission indication information, where the PDU session modification request message includes service data flow description information and a user permanent identity SUPI;

the session management function network element is configured to receive the PDU session modification request message, and send a policy association update request message to the second policy control function network element, where the policy association update request message includes the service data flow description information and the SUPI;

the second policy control function network element, configured to receive the policy association update request message, and send a data query request message to the second UDR, where the data query request message includes the service data flow description information, the user permanent identity SUPI, and a data network name DNN, and the data query request message is used to request a background data transfer policy, where the background data transfer policy corresponds to the DNN, the SUPI, and the service data flow description information;

and the second UDR is used for receiving the data query request message and sending the background data transmission strategy to the second strategy control function network element according to the data query request message.

According to the system provided by the present application, the second policy control function network element may obtain the background data transfer policy from the UDR based on the service data flow description information, the DNN, and the SUPI. Compared with the method that the application function network element sends the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user (or called terminal equipment), the method can save signaling overhead because the application function network element does not need to send the background data transmission strategy authorization request message to the second strategy function network element at the granularity of the user any more.

In a possible implementation manner, the data query request message further includes single network slice selection assistance information S-NSSAI, and the background data transmission policy further corresponds to the S-NSSAI.

It should be understood that the first UDR and the second UDR in the sixth aspect may be the same, but the application does not limit this. The first UDR may correspond to the UDR in the first and second aspects, and the second UDR may correspond to the UDR in the third to fifth aspects. Reference may be made to the description of the first to fifth aspects above in relation to the sixth aspect.

In a seventh aspect, an apparatus is provided that includes means for performing the method of any one of the possible implementations of the first to fifth aspects and the first to fifth aspects.

In an eighth aspect, an apparatus is provided that includes a processor. The processor is coupled to the memory and is operable to execute the instructions in the memory to cause the apparatus to perform the method of any one of the possible implementations of the first to fifth aspects and the first to fifth aspects. Optionally, the apparatus further comprises a memory. Optionally, the apparatus further comprises an interface circuit, the processor being coupled to the interface circuit.

In one implementation, the apparatus is a terminal device or a chip configured in the terminal device. When the apparatus is a terminal device, the interface circuit may be a transceiver, or an input/output interface. When the apparatus is a chip configured in a terminal device, the interface circuit may be an input/output interface.

In another implementation manner, the apparatus is a second policy control function network element or a chip configured in the second policy control function. When the apparatus is a second policy control function network element, the interface circuit may be a transceiver, or an input/output interface. When the apparatus is a chip configured in the second policy control function network element, the interface circuit may be an input/output interface.

In yet another implementation, the apparatus is a UDR or a chip configured in a UDR. When the device is a UDR, the interface circuit may be a transceiver, or an input/output interface. When the device is a chip configured in a UDR, the interface circuit may be an input/output interface.

Alternatively, the transceiver may be a transmit-receive circuit. Alternatively, the input/output interface may be an input/output circuit.

In a ninth aspect, there is provided a processor comprising: input circuit, output circuit and processing circuit. The processing circuit is configured to receive a signal through the input circuit and transmit a signal through the output circuit, so that the processor performs the method of any one of the possible implementations of the first to fifth aspects and the first to fifth aspects.

In a specific implementation process, the processor may be a chip, the input circuit may be an input pin, the output circuit may be an output pin, and the processing circuit may be a transistor, a gate circuit, a flip-flop, various logic circuits, and the like. The input signal received by the input circuit may be received and input by, for example and without limitation, a receiver, the signal output by the output circuit may be output to and transmitted by a transmitter, for example and without limitation, and the input circuit and the output circuit may be the same circuit that functions as the input circuit and the output circuit, respectively, at different times. The embodiment of the present application does not limit the specific implementation manner of the processor and various circuits.

In a tenth aspect, a processing apparatus is provided that includes a processor and a memory. The processor is configured to read instructions stored in the memory, and may receive a signal via the receiver and transmit a signal via the transmitter to perform the method of any one of the possible implementations of the first to fifth aspects and the first to fifth aspects.

Optionally, the number of the processors is one or more, and the number of the memories is one or more.

Alternatively, the memory may be integral to the processor or provided separately from the processor.

In a specific implementation process, the memory may be a non-transient memory, such as a Read Only Memory (ROM), which may be integrated on the same chip as the processor, or may be separately disposed on different chips.

The processing device in the tenth aspect may be a chip, the processor may be implemented by hardware or software, and when implemented by hardware, the processor may be a logic circuit, an integrated circuit, or the like; when implemented in software, the processor may be a general-purpose processor implemented by reading software code stored in a memory, which may be integrated with the processor, located external to the processor, or stand-alone.

In an eleventh aspect, there is provided a computer program product comprising: a computer program (which may also be referred to as code, or instructions), which when executed, causes a computer to perform the method of any of the possible implementations of the first to fifth aspects and of the first to fifth aspects described above.

In a twelfth aspect, a computer-readable medium is provided, which stores a computer program (which may also be referred to as code or instructions) that, when executed on a computer, causes the computer to perform the method of any one of the possible implementations of the first to fifth aspects and the first to fifth aspects.

Drawings

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

FIG. 2 is a schematic diagram of another system architecture provided by embodiments of the present application;

FIG. 3 is a schematic diagram of the architecture of a 5G system applied to the present application;

fig. 4 is a schematic architecture diagram of a 5G system applied to the local access roaming of the present application;

fig. 5 is an architecture diagram of a 5G system applied to home access roaming of the present application;

FIG. 6 is a schematic block diagram of an apparatus for use in embodiments of the present application;

FIG. 7 is a schematic flow chart diagram of a method for background data transmission provided herein;

FIG. 8 is a schematic flow chart diagram of another method for background data transmission provided herein;

fig. 9 is a schematic block diagram of a communication device provided herein.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

The technical scheme of the embodiment of the application can be applied to various communication systems, for example: long Term Evolution (LTE) systems, LTE Frequency Division Duplex (FDD) systems, LTE Time Division Duplex (TDD) systems, Universal Mobile Telecommunications System (UMTS), universal microwave access (WiMAX) communication systems, fifth generation (5G) systems (e.g., New Radio (NR)) and new communication systems that may appear in the future, and the like.

Fig. 1 is a schematic diagram of a system architecture provided in an embodiment of the present application. As shown in fig. 1, the system 100 includes: a terminal device 110 and a first policy control function network element 120. The system 100 described above may be used to perform the method for background data transmission provided herein. Optionally, the system 100 may further include a Unified Data Repository (UDR) 130 and an application function network element 140. It should be understood that UDR 130 is the first UDR in this application.

The first policy control function network element 120 is configured to:

first, at least one time window information and at least one transmission indication information are obtained. Wherein, the at least one time window information is in one-to-one correspondence with the at least one transmission indication information. The first transmission indication information is used to indicate a transmission type of the background data transmission that can be performed in a first time window indicated by the first time window information, the first time window corresponds to the first transmission indication information, the first transmission indication information is any one of the at least one transmission indication information, and the first time window information is any one of the at least one time window information.

The user routing policy is then sent to end device 110. Wherein the user routing policy includes the at least one time window information and the at least one transmission indication information.

Accordingly, terminal device 110 is configured to:

the user routing policy sent by the first policy control function network element 120 is received. And triggering PDU session establishment or a modification process in the first time window according to the first transmission indication information so as to transmit background data in the first time window.

It should be understood that the number of the at least one time window information and the number of the at least one transmission indication information are both K, K being a positive integer. If K is 1, the time window information acquired by the first policy control function network element 120 corresponds to the transmission indication information. If K is greater than 1, any one of the K pieces of time window information corresponds to only one piece of transmission indication information of the K pieces of transmission indication information, and any two pieces of time window information cannot correspond to the same piece of transmission indication information, and one piece of transmission indication information of the K pieces of transmission indication information corresponds to only any one of the K pieces of time window information, and any two pieces of transmission indication information cannot correspond to the same piece of time window information. For example, K2 indicates time window information #1 and time window information #2, K transmission indication information indicates transmission indication information #1 and transmission indication information #2, time window information #1 corresponds to transmission indication information #1, and time window information #2 corresponds to transmission indication information # 2.

For example, if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is uplink transmission, the terminal device triggers PDU session establishment or a PDU session modification procedure when it is determined that the background data transmission needs to be initiated in the first time window.

For example, if uplink background data transmission is required only at time t after a first time window starts for a period of time, the terminal device may trigger the PDU session establishment or modification procedure only at time t, and does not need to trigger the PDU session establishment or modification procedure at the start of the time window, thereby avoiding network resource overhead caused by maintaining a session context and saving network resources to a certain extent.

For another example, if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is downlink transmission, or downlink transmission and uplink transmission, the terminal device may trigger PDU session establishment or a PDU session modification procedure when the first time window starts.

Since the AF, for example, the application function network element 140, does not sense the timing of initiating the service request to the terminal device, when the background data transmission required in the first time window is downlink transmission, or downlink transmission and uplink transmission, by triggering PDU session establishment or a PDU session modification procedure at the beginning of the first time window, the problem that the special PDU session for the background data transmission service is not established yet at the beginning of the downlink data transmission and the background data transmission service cannot be normally transmitted can be avoided.

Optionally, the user routing policy may further include at least one Network Area Information (NAI).

Wherein the at least one network area information corresponds to the at least one time window information and the at least one transmission indicator information one to one. A first network area indicated by first network area information of the at least one network area information corresponds to the first time window and the first transmission indication information. In case that the terminal device 110 is located in the first network area, the terminal device 110 may trigger the PDU session establishment or the PDU session modification procedure within the first time window according to the first transmission indication information. In case the terminal device 110 is not in the first network region, the terminal device 110 is not capable of background data transmission, and thus there is no need to trigger the PDU session setup or modify the procedure within the first time window.

It should be noted that, in this application, the terminal device 110 may Match, according to the priority of the user routing policy, the to-be-initiated background data transmission service with the Traffic Descriptor (Traffic Descriptor) in the received user routing policy in sequence, and if a specific user routing policy is matched (the user routing policy may also be a default user routing policy, for example, the Traffic Descriptor is in a Match-all form), the terminal device 110 determines whether a PDU session conforms to the definition of the routing Descriptor (RSD) in the matched user routing policy.

If one or more of a Data Network Name (DNN), single network slice selection assistance information (S-NSSAI), Session and Service Continuity (SSC) mode (mode) and other information corresponding to a PDU session are consistent with corresponding information in a matched user routing policy, terminal device 110 may select to trigger a PDU session modification procedure by sending a PDU session modification request message based on the existing PDU session.

If none of the existing PDU sessions matches the RSD information of the matched user routing policy, terminal device 110 will trigger the PDU session establishment procedure by sending a PDU session establishment request message.

In addition, as will be understood by those skilled in the art, the background data transmission policy negotiated in advance by the application function network element 140 with the policy control function network element performing the background data transmission policy negotiation includes the at least one time window information and the at least one transmission indication information. After negotiating the context data transfer policy, the context data transfer policy may be stored in the UDR 130. The policy control function network element performing the background data transmission negotiation may be the same network element as the first policy control function network element 120, or may not be the same network element, which is not limited in this application.

The process of negotiating the background data transmission policy may refer to the prior art, and will not be described in detail in this application.

In a possible implementation manner, the first policy control function network element 120 may obtain the at least one time window information and the at least one transmission indication information from a background data transmission policy negotiation request message sent by the application function network element 140.

It can be understood that, in this manner, the time window information and the transmission indication information requested by the application function network element 140 are the same, namely the time window information and the transmission indication information in the negotiated background data transmission policy.

Generally, the background data transmission negotiation executed by the policy control function network element mainly needs to judge whether a data transmission request of the terminal device is supported in a time window, and determine the rate and bandwidth information according to the number of the terminal devices and the data transmission amount of each terminal device. Thus, the time window information and the transmission indication information in the negotiated background data transmission policy are generally the same as the time window information and the transmission indication information requested by the application function network element 140.

It should be understood that in this manner, the first policy control function network element 120 may be a policy control function network element that performs context data transmission negotiation.

In another possible implementation, the first policy control function network element 120 may obtain the at least one time window information and the at least one transmission indication information from the negotiated background data transmission policy.

For example, if the first policy control function network element 120 is a policy control function network element that performs a negotiation for background data transmission, the first policy control function network element 120 may directly obtain the at least one time window information and the at least one transmission indication information from the negotiated background data transmission policy, that is, the negotiated background data transmission policy includes the at least one time window information and the at least one transmission indication information.

It should be understood that, in this manner, the time window information and the transmission indication information in the negotiated background data transmission policy may be different from the time window information and the transmission indication information requested by the application function network element 140, but this is not limited in this embodiment of the present application.

In yet another possible implementation, the first policy control function network element 120 may obtain the at least one time window information and the at least one transmission indication information from the UDR 130. That is, the UDR 130 may send the at least one time window information and the at least one transmission indication information to the first policy control function network element 120.

For example, the first policy control function network element 120 may subscribe to an Application Data (Application Data) update event corresponding to the terminal device 110 in advance, or subscribe to an Application Data update event of an Application Service Provider (ASP) Identifier (ID) corresponding to the terminal device 110, so that after the policy control function network element performing the context Data negotiation stores the negotiated context Data transmission policy in the UDR 130, the UDR 130 may send the at least one time window information and the at least one transmission indication information in the negotiated context Data transmission policy to the first policy control function network element 120.

It should be understood that, in this manner, the policy control function network element performing context data negotiation may be different from the first policy control function network element 120, but this is not limited in this embodiment of the present application.

In summary, the first policy control function network element provides, to the terminal device, the transmission indication information corresponding to each time window information, so that the terminal device can trigger the PDU session establishment or the PDU session modification process based on the transmission type of the background data transmission that can be performed in the time window indicated by each time window information, thereby using the network resources more reasonably and solving the problem of wasting the network resources in the prior art.

In one technique, when background data transmission is required, when a time window starts, an application function network element triggers a background data transmission policy authorization request message with a terminal device granularity, where the background data transmission policy authorization request message carries a reference (reference) Identifier (ID) of a previously negotiated background data transmission policy, so that a policy control function network element obtains the background data transmission policy from a UDR. However, the number of terminal devices that need to perform background data transmission may be large, for example, many camera sensors in a region under a car networking scene need to send uplink data, and then more signaling interaction will be involved between the application function network element and the policy control function network element, thereby bringing about a large signaling overhead.

In view of the above, the present application provides a mechanism for the UDR to store the background data transmission policy, and provides a method for background data transmission based on the mechanism. The mechanism can be independent of the existing mechanism for storing the background data transmission strategy by the UDR, and can also be used as a substitute for the existing mechanism for storing the background data transmission strategy by the UDR.

Specifically, compared with the prior art in which the policy control function network element stores the background data transmission policy to the policy data with the BDT reference ID as the key value, so that the subsequent policy control function network element queries the corresponding background data transmission request with the BDT reference ID, the manner of storing the background data transmission by the policy control function network element responsible for negotiating the background data transmission policy provided in the present application may be any one of the following manners.

It should be understood that S-NSSAI (O) in the following description means S-NSSAI as an optional parameter.

In a first mode

After the policy control function network element executes the context data transmission policy negotiation, the policy control function network element may store the context data transmission policy to the session management policy subscription data in the UDR, where the data key value is a user permanent identifier (SUPI) + DNN + S-NSSAI (o), where the SUPI information is mapped by an Internal Group ID in a context data transmission policy negotiation request received by the policy control function network element (where the context data transmission policy negotiation request sent by the application function network element includes the External Group ID, NEF is responsible for mapping the External Group ID to the Internal Group identifier Internal Group ID), and the DNN and S-NSSAI information are configured according to an operator, for example, the operator configures a specific DNN + S-NSSAI (optional) for the context data transmission; at this time, the second policy control function network element may obtain the session management policy subscription data returned by the UDR by only sending a data query request message to the UDR without sensing DNN + S-NSSAI and carrying the SUPI + DNN + S-NSSAI (o).

Mode two

The background data transmission may be saved as application data keyed by SUPI + DNN + S-NSSAI (o), wherein SUPI, DNN, and S-NSSAI may be obtained in the manner described in manner one; at this time, the second policy control function network element needs to perceive the current request as a background data transmission service according to the SUPI + DNN + S-nssai (o), and sends a data query request message carrying the SUPI + DNN + S-nssai (o) to the UDR, so as to obtain the application data returned by the UDR.

Mode III

The background data transfer may be stored as application data keyed by SUPI + SDF description information + DNN + S-nssai (o). And the second policy control function network element acquires the background data transmission policy from the UDR according to SDF description information + DNN + S-NSSAI (O), wherein the SDF description information may contain ASP ID or quintuple information. When the SDF description information is quintuple information, the second policy control function network element may map the SDF description information to an ASP ID according to the local configuration information, and the mapping action may also be performed by the UDR, that is, the SM policy control function network element sends the SDF description information + DNN + S-nssai (o), and the UDR obtains the background data transmission policy according to the SDF description information, the local configuration information, and the stored background data transmission policy.

Based on the above mechanism for storing the background data transmission policy, in another method for background data transmission provided by the present application, a policy control function network element (i.e., a second policy control function network element hereinafter) may obtain a corresponding background data transmission policy from a UDR based on a DNN or a DNN and service flow description information, and this method may omit an operation of an application function network element sending a background data transmission policy authorization request message for each terminal device, thereby being capable of saving signaling overhead. In brief, in the prior art, before the policy control function network element obtains the background data transmission policy from the UDR, the application function network element needs to send a background data transmission policy authorization request message to the policy control function network element first, but the application does not need to send a background data transmission policy authorization request message to the policy control function network element. This is described in detail below in connection with system 200.

Fig. 2 is a schematic diagram of another system architecture provided in the embodiment of the present application. As shown in fig. 2, the system 200 includes: a second policy control function network element 210 and a UDR 220. The system 200 may be used to perform another method for background data transmission as provided herein. Optionally, the system 200 may further include a session management function network element 230 and a terminal device 240. It should be understood that UDR 220 is the second UDR in this application.

In one possible implementation, the second policy control function network element 210 is configured to receive a policy association creation request message, where the policy association creation request message includes a DNN and a SUPI; transmitting a data query request message including the DNN and the SUPI to the UDR 220, the data query request message for requesting a background data transfer policy; and receiving a background data transmission strategy corresponding to the DNN and the SUPI sent by the UDR.

Accordingly, the UDR 220 is configured to receive the data query request message sent by the second policy control function network element 210; and, according to the data query request message, sending the background data transmission policy to the second policy control function network element 210.

Specifically, the terminal device 240 may trigger the PDU session setup procedure by sending a PDU session setup request message to the session management function network element 230, wherein the PDU session setup request message includes the DNN and the SUPI. After receiving the PDU session establishment request message, the session management function network element 230 may send the policy association establishment request message to the second policy control function network element 210.

For example, when receiving the policy association creation request message, the second policy control function network element 210 may send a data query request message to the UDR 220 if determining that the service corresponding to the DNN and the SUPI is a background data transfer service, where the data query request message carries the DNN and the SUPI to obtain the background data transfer policy from the UDR 220.

Optionally, the PDU session setup request message may also include an S-NSSAI. Accordingly, the policy association creation request message and the data query request message may further include the S-NSSAI. The S-NSSAI corresponds to the background data transmission policy.

Therefore, according to the system provided by the present application, the second policy control function network element may obtain the background data transmission policy from the UDR based on the DNN and the SUPI corresponding to the PDU session requested to be established by the terminal device, and avoid the application function network element sending the background data transmission policy authorization request message to the second policy function network element at per-user granularity, thereby saving signaling overhead.

In another possible implementation manner, the second policy control function network element 210 is configured to receive a policy association update request message, where the policy association update request message includes Service Data Flow (SDF) description information and SUPI; transmitting a data query request message including the service data flow description information, the SUPI, and the DNN to the UDR 220, the data query request for requesting a background data transfer policy; and receiving a background data transmission policy sent by the UDR, wherein the background data transmission policy corresponds to the service data flow description information, the SUPI and the DNN.

Specifically, the terminal device 240 may trigger the PDU session modification procedure by sending a PDU session modification request message to the session management function network element 230, wherein the PDU session modification request message includes the service data flow description information and the SUPI. Further, the PDU session modification request message may also include quality of service parameter information. After receiving the PDU session modification request message, the session management function network element 230 may send the policy association update request message to the second policy control function network element 210, where the policy association update request message carries the service data flow description information and may further carry the service quality parameter information.

For example, upon receiving the policy association update request message, the second policy control function network element 210 may send a data query request message to the UDR 220 to obtain the context data transmission policy from the UDR 220 if it is determined that the current service is a context data transmission service according to the service data flow description information and the SUPI. Wherein the data query request message may include the service data flow description information, the SUPI, and the DNN.

Those skilled in the art will understand that the service data flow description information is used to describe the traffic flow for the terminal device initiated PDU session modification corresponding to the policy association update request message. The policy association update request message is used to request for updated policy rule information, and the policy association update request message may carry an event subscribed by the second policy control function network element 210, such as a resource modification request event initiated by the terminal device 240. The DNN is obtained by the second policy control function network element when the PDU session is established, represents a specific data network name corresponding to the PDU session, and determines a mode or an access technology by which the terminal device accesses the network. The SUPI represents a user permanent identity as a globally unique identity for a subscriber.

Optionally, the data query request message may further include an S-NSSAI, the S-NSSAI corresponding to the background data transmission policy.

Therefore, according to the system provided by the present application, the second policy control function network element may obtain the background data transmission policy from the UDR based on the service data flow description information, the SUPI, and the DNN corresponding to the PDU session requested to be modified by the terminal device, so as to avoid the application function network element sending the background data transmission policy authorization request message to the second policy function network element at the user granularity, thereby saving signaling overhead.

It should be noted that the scheme described based on system 200 may also be used in combination with the scheme described based on system 100, in which case terminal device 110 and terminal device 240 are the same terminal device, and UDR 130 and UDR 220 are the same UDR. And, the terminal device may send a PDU session setup request message to the session management function network element 230 to trigger the PDU session setup procedure or send a PDU session modification request message to trigger the PDU session modification procedure based on the first transmission indication information.

It should be understood that each network element in the system 100 and the system 200 may be a single network element, or each of these network elements may be a functional module, or the functions implemented by any multiple network elements in these network elements may be integrated on a functional module or a network element, which is not limited in this application.

In addition, the terminal device in the embodiment of the present application may refer to a User Equipment (UE), an access terminal, a terminal in V2X communication, a subscriber unit, a subscriber station, a mobile station, a remote terminal, a mobile device, a user terminal, a wireless communication device, a user agent, or a user equipment. The terminal device may also be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in a future 5G network or a terminal device in a future evolved Public Land Mobile Network (PLMN), and the like, which are not limited in this embodiment. The terminal device may also include a V2X device, for example, a vehicle or an On Board Unit (OBU) in a vehicle.

Alternatively, the system 100 and the system 200 may be a 5G system and other possible networks in the future, and the embodiment of the present application is not particularly limited thereto.

For example, the terminal device 110, the first policy control function network element 120, and the application function network element 140 in the system 100 may be a UE, an access and mobility control (AM) Policy Control Function (PCF), and an Application Function (AF) in a 5G system, respectively. The second policy control function network element 210, the session management function network element 230, and the terminal device 240 in the system 200 may be a Session Management (SM) PCF, a Session Management Function (SMF), and a UE in the 5G system, respectively.

The following will illustrate the 5G system in different scenarios with reference to fig. 3 to 5. It should be understood that the 5G system described herein is an example only and should not be construed as limiting the present application in any way.

Fig. 3 shows a basic architecture diagram of a 5G system 300. As shown in fig. 3, the system 300 includes: access and mobility management function (AMF), Session Management Function (SMF), Radio Access Network (RAN), Unified Data Management (UDM), Policy Control Function (PCF), Data Network (DN), User Plane Function (UPF), UE, Application Function (AF), and UDR.

The main functions of each network element are described as follows:

AF: and (5) applying a function. Requirements of the application side on the network side, such as quality of service (QoS) requirements, are mainly transferred. The AF may be a third party functional entity, or may be an application service deployed by an operator, such as an IP Multimedia Subsystem (IMS) voice call service.

UDM: and (5) unified data management. The system is mainly responsible for functions of managing subscription data, user access authorization and the like.

UDR: a unified data warehouse. The access function of the type data such as subscription data, strategy data, application data and the like is mainly responsible.

PCF: a policy control function. The method is mainly responsible for carrying out charging, QoS bandwidth guarantee and mobility management, UE strategy decision and other strategy control functions aiming at the conversation and service flow level. In the system, PCFs connected to the AMF and the SMF are an access and mobility control PCF (AM PCF) and a session management PCF (SM PCF) respectively, and the AM PCF and the SM PCF may not be the same PCF entity in actual deployment.

SMF: a session management function. The method mainly has the functions of session management, execution of control strategies issued by PCF, UPF selection, UE IP address allocation and the like.

AMF: access and mobility management functions. Mainly performs the functions of mobility management, access authentication/authorization and the like. In addition, the method is also responsible for transferring the user policy between the UE and the PCF.

UPF: a user plane functional entity. And the UPF is used as an interface with a data network to complete functions of user plane data forwarding, session/stream level-based charging statistics, bandwidth limitation and the like.

(R) AN: the (wireless) access network corresponds to different access networks in the 5G, and has various modes such as wireless access, wireless base station access and the like.

PDU conversation: the Session service for PDU connectivity between the UE and the data network may be identified by a PDU Session ID.

Wherein, each interface function is described as follows:

n7: and the interface between the PCF and the SMF is used for transmitting the PDU session granularity and the service data flow granularity control strategy.

N15: and the interface between the PCF and the AMF is used for issuing the UE strategy and the access control related strategy.

N5: and the interface between the AF and the PCF is used for issuing the application service request and reporting the network event.

N4: the interface between the SMF and the UPF is used for transmitting information between the control plane and the user plane, and comprises the control of issuing of forwarding rules, QoS control rules, flow statistic rules and the like facing the user plane and the information reporting of the user plane.

N11: and the interface between the SMF and the AMF is used for transmitting PDU session tunnel information between the RAN and the UPF, transmitting control information sent to the UE, transmitting radio resource control information sent to the RAN and the like.

N2: and the interface between the AMF and the RAN is used for transmitting radio bearer control information from the core network side to the RAN and the like.

N1: the interface between the AMF and the UE, access independence, is used to deliver QoS control rules to the UE, etc.

N8: and the interface between the AMF and the UDM is used for acquiring the subscription data and the authentication data related to access and mobility management from the UDM by the AMF, registering the current mobility management related information of the UE from the UDM by the AMF and the like.

N10: and the interface between the SMF and the UDM is used for acquiring the subscription data related to the session management from the SMF to the UDM, registering the related information of the current session of the UE from the SMF to the UDM, and the like.

N35: and the interface between the UDM and the UDR is used for acquiring the user subscription data information from the UDR by the UDM.

N36: and the interface between the PCF and the UDR is used for the PCF to acquire the subscription data related to the strategy and the application data related information from the UDR.

N3: an interface between the RAN and the UPF for transferring user plane data between the RAN and the UPF. .

N6: and the interface between the UPF and the DN is used for transmitting the user plane data between the UPF and the DN.

N9: the interface between the UPFs, such as the interface between a visited-policy control function (V-PCF) and a home-policy control function (H-PCF), or the interface between the UPF connected to the DN and the UPF connected to the RAN, is used to transfer user plane data between the UPFs.

The third generation partnership project (3 GPP) standard defines two roaming modes for a user to access at a visited location, namely, a local roaming mode (local roaming) mode and a home-roaming mode (home-roaming) mode, which correspond to the systems shown in fig. 4 and 5, respectively.

Fig. 4 shows an architectural diagram of a 5G system 400 for local access roaming. As shown in fig. 4, the system 400 includes: AMF, SMF, (R) AN, UDM, visited-policy control function (V-PCF), home-policy control function (H-PCF), DN, UPF, UE, AF, and UDR. Wherein the interface between the V-PCF and the H-PCF is N24. It should be understood that in fig. 4, other network elements are located on the visited public land mobile network (V-PLMN) side, except that the UDM, UDR and H-PCF are located on the home public land mobile network (H-PLMN) side.

Referring to fig. 4, in the roaming architecture, the AMF and the SMF are both located at the visited place, and at this time, the session management function is executed by the SMF function entity at the visited place. In addition, the V-PCF connected to the AMF and the V-PCF connected to the SMF correspond to an AM PCF and an SM PCF, respectively, and the AM PCF and the SM PCF may not be the same PCF entity in an actual scene. The user routing strategy related to the present application can be provided by the H-PCF in the architecture.

Fig. 5 shows an architectural diagram of a 5G system 500 for home access roaming. FIG. 5 differs from FIG. 4 in that a home user plane function (H-UPF) and a home session management function (H-SMF) are added to system 500. That is, both the V-PLMN side and the H-PLMN side contain UPFs and SMFs. The UPF of the V-PLMN side is connected with the UPF of the H-PLMN side through an N9 interface, and the UPF of the H-PLMN side is connected with the DN through an N9 interface; the V-SMF on the V-PLMN side is connected with the H-SMF on the H-PLMN side through an N11 interface, the H-SMF is connected with the UPF on the H-PLMN side through an N4 interface, and the H-SMF is connected with the UDM through an N10 interface. The H-PCF interfaces with the AF via an N5 interface.

Referring to fig. 5, in the roaming architecture, the AMF is located at a visited place, and the session management function is performed by the H-SMF. In addition, the H-PCF connected with the V-PCF and the H-PCF connected with the H-SMF respectively correspond to the AM PCF and the SM PCF in the application, and the AM PCF and the SM PCF may not be the same PCF entity or may be the same PCF entity in an actual scene. The user routing strategy related to the present application can be provided by the H-PCF in the architecture.

It should be understood that the SM PCF is a policy control function entity connected to the SMF, responsible for performing the session management policy rule decision function. The AM PCF is a policy rule decision function in charge of executing an access control policy and a UE policy by a policy control function entity directly connected to the AMF.

It should be noted that the name of each network element (such as V-PCF, H-PCF, AMF, etc.) included in fig. 3 to fig. 5 is only a name, and the name does not limit the function of the network element itself. In the 5G network and other networks in the future, the network elements may also be given other names, which is not specifically limited in the embodiment of the present application. For example, in a 6G network, some or all of the above network elements may use the terminology in 5G, or may use other nomenclature, and so on, which are described herein in a unified manner and will not be described again below. Similarly, the interfaces between the network elements shown in fig. 3 to fig. 5 are only an example, and in a 5G network and other networks in the future, the interfaces between the network elements may not be the interfaces shown in the figures, which is not limited in this application.

In addition, it should be further noted that the present application may be applied to a service architecture, and each network element may also communicate with another network element by using a service message.

The specific operation process and beneficial effects of the network elements in the systems of fig. 1 to 5 can be referred to the description of the method embodiments below.

Any of the network elements shown in fig. 1 and 2 may be implemented in the manner of the apparatus 600 shown in fig. 6.

Fig. 6 is a schematic diagram of an apparatus 600 provided in an embodiment of the present application. The apparatus 600 may be any network element to which the present application relates, and may implement the functions that are implemented by the network element described herein.

It is understood that the communication apparatus 900 may be a physical device, a component (e.g., an integrated circuit, a chip, etc.) of the physical device, or a functional module in the physical device.

For example, communications apparatus 900 can be utilized to implement the functionality of a terminal device as described herein. For example, the communication apparatus 900 may be a terminal device, a component (e.g., an integrated circuit, a chip, etc.) in the terminal device, or a functional module.

As another example, the communications apparatus 900 can be used to implement the functionality of the second policy control function network element described herein. For example, the communication apparatus 900 may be a second policy control function network element, a component (e.g., an integrated circuit, a chip, etc.) in the second policy control function network element, or a functional module in the second policy control function network element.

The apparatus 600 may be used to implement the methods provided herein, and the apparatus 600 may include one or more processors 601.

The processor 601 may also be referred to as a processing unit and may implement certain control functions. The processor 601 may be a general purpose processor or a special purpose processor, etc. For example, a baseband processor or a central processor. The baseband processor may be configured to process a communication protocol and communication data, and the central processor may be configured to control a communication device (e.g., a terminal device, a first policy control function network or a second policy control function network element, etc.), execute a software program, and process data of the software program.

In an alternative design, the processor 601 may also have instructions 603 stored therein, and the instructions 603 may be executed by the processor, so that the apparatus 600 performs the method described in the method embodiment of the present application.

In an alternative design, the processor 601 may include a transceiver unit to perform receive and transmit functions. The transceiving unit may be, for example, a transceiving circuit, or an interface circuit. The transmit and receive circuitry, interfaces or interface circuitry used to implement the receive and transmit functions may be separate or integrated. The transceiver circuit, the interface circuit or the interface circuit may be used for reading and writing code/data, or the transceiver circuit, the interface circuit or the interface circuit may be used for transmitting or transferring signals.

In yet another possible design, the apparatus 600 may include a circuit that may implement the functions of transmitting or receiving or communicating in the method embodiments of the present application.

Optionally, the apparatus 600 may further include one or more memories 602 on which instructions 606 may be stored, and the instructions may be executed on the processor 601, so that the apparatus 600 performs the method described in the method embodiment of the present application. Optionally, the memory 602 may further store data. The processor 601 and the memory 602 may be provided separately or integrated together.

Optionally, the apparatus 600 may further comprise a transceiver 605 and/or an antenna 606. The processor 601, which may be referred to as a processing unit, controls the apparatus 600. The transceiver 605 may be referred to as a transceiving unit, a transceiver, a transceiving circuit or a transceiver, etc. for implementing transceiving function.

The apparatus 600 may illustratively be a general-purpose computer device or a special-purpose computer device. In a specific implementation, the apparatus 600 may be a desktop computer, a laptop computer, a web server, a Personal Digital Assistant (PDA), a mobile phone, a tablet computer, a wireless terminal device, a communication device, an embedded device, or a device with a similar structure as in fig. 6. Embodiments of the invention are not limited by the type of device 600.

In addition, the network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not constitute a limitation to the technical solution provided in the embodiment of the present application, and it can be known by a person skilled in the art that the technical solution provided in the embodiment of the present application is also applicable to similar technical problems along with the evolution of the network architecture and the appearance of a new service scenario.

To better understand the present application, the method for background data transmission provided in the present application is exemplified below in conjunction with the 5G system described herein.

It should be understood that the UE, the AF, the AM PCF, the SM PCF, and the SMF in the method described below correspond to the terminal device, the application function network element, the first policy control function network element, the second policy control function network element, and the session management function network element in the system described above in sequence. The AM PCF and the SM PCF may or may not be the same PCF.

Fig. 7 shows a schematic flow chart of a method 700 for background data transmission according to an embodiment of the present application. In the method 700, the AM PCF may obtain the at least one time window information and the at least one transmission indication information from a background data transmission policy negotiation request message sent by the AF. The steps shown in fig. 7 will be explained below.

S701, the AF sends a background data transmission strategy negotiation request message to the AM PCF.

Wherein the context data transmission policy negotiation request message includes the at least one time window information and the at least one transmission indication information. In addition, the context data transmission policy negotiation request message may further include information such as ASP ID, Number of terminal devices (e.g., Number of UEs), amount of data transferred by each terminal device (Volume per UE), External Group Identifier (External Group Identifier), requested or expected time window (Desired time window), requested transmission indication information corresponding to the requested time window, and network area information.

It should be understood that, in the present application, the requested time window is the at least one time window information, and the requested transmission indication information is the at least one transmission indication information.

S701 differs from the prior art in that the background data transmission policy negotiation request message further includes the requested transmission indication information. The specific meaning of other information included in the background data transmission policy negotiation request message, except for the requested time window and the requested transmission indication information, may refer to the prior art, and is not described in detail in this application.

S702, the AM PCF and the AF perform the subsequent procedure of negotiating the background data transmission policy.

After receiving the background data transmission policy negotiation request message sent by the AF, the AM PCF may specifically refer to the prior art for how to negotiate the background data transmission policy with the AF, and details are not described here. As will be understood by those skilled in the art, after the AM PCF negotiates with the AF to obtain the background data transmission policy, the AM PCF may store the negotiated background data transmission policy in the UDR.

S703, the AM PCF sends the user routing strategy to the AMF. Accordingly, the AMF receives the user routing policy.

When the AM PCF determines that the related information of the background data transmission strategy needs to be sent to the UE in a user routing strategy mode, the AM PCF sends the user routing strategy to the AMF, and the user routing strategy comprises at least one time window information and at least one transmission indication information. Optionally, the user routing policy further comprises the at least one network area information.

Alternatively, the AM PCF may send the user routing policy through the Namf _ Communication _ N1N2MessageTransfer in the existing protocol, but the present application is not limited thereto.

S704, the AMF sends the user routing policy to the UE. Accordingly, the UE receives the user routing policy.

Specifically, the AMF sends the user routing policy to the (R) AN, which sends the user routing policy to the UE.

When the UE is in an idle state, the AMF needs to initiate a service request (service request) procedure to page the UE before sending the user routing policy.

Alternatively, the AMF may send the user routing policy through delivery UE policy delivery of UE policies in the existing protocol).

S705, the UE sends the first feedback information to the AMF. Accordingly, the AMF receives the first feedback information.

Specifically, the UE transmits the first feedback information to the (R) AN, which transmits the first feedback information to the AMF.

Wherein the first feedback information indicates that the UE correctly receives the user routing strategy. Alternatively, the first feedback information may be signaled as a result of the delivery of UE policies (policies) by UE policies in existing protocols.

S706, the AMF sends the first feedback information to the AM PCF.

Accordingly, the AM PCF receives the first feedback information. The AM PCF can know that the UE correctly receives the first feedback information through the first feedback information.

Optionally, the AMF sends the first feedback information through a Namf _ N1MessageNotify in the existing protocol.

S707, for any time window information in the at least one first time window information, that is, the first time window information in the foregoing, the UE triggers a PDU session establishment or a PDU session modification procedure within the first time window according to the first transmission indication information.

Specifically, the UE may send a PDU session setup request message or a PDU session modification request message in the first time window according to the first transmission indication information, specifically send the PDU session setup request message or send the PDU session modification request message, which may refer to the description made above when describing the system 100, and is not described herein again.

For example, if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is uplink transmission, the UE triggers PDU session establishment or a PDU session modification procedure when it is determined that the background data transmission needs to be initiated in the first time window.

For example, if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is downlink transmission, or downlink transmission and uplink transmission, the UE triggers a PDU session establishment or a PDU session modification procedure when the first time window starts.

Optionally, as described above, the UE may further trigger the PDU session establishment or the PDU session modification procedure within the first time window according to the first transmission indication information in combination with the first network area information when the UE is located in the first network area.

It should be understood that the present application does not limit the sequencing of S707 and S705.

S708, after receiving the PDU session establishment request or modification message, the SMF sends a policy association establishment or modification request message to the SM PCF.

Specifically, if the SMF receives a PDU session establishment request message, the SMF sends a policy association establishment request message to the SM PCF, where the policy association establishment request message includes the DNN and the SUPI corresponding to the PDU session requested to be established. It should be understood that the PDU session setup request message also includes the DNN and SUPI. Further, the PDU session setup request message and the policy association creation request message may further include an S-NSSAI corresponding to the PDU session.

If the SMF receives the PDU session modification request message, the SMF sends a policy associated modification request message to the SM PCF, wherein the policy associated modification request message comprises the service data flow description information and the SUPI corresponding to the PDU session requested to be modified. It should be understood that the PDU session modify request message also includes the service data flow description information and the SUPI. The service data flow description information is used to describe a service flow for PDU session modification initiated by the UE, and the flow description information may include an application identifier to be initiated by the UE, or description information in a quintuple (source address, destination address, source port, destination port, protocol type) form of the service to be initiated, or other forms, which is not described herein again. Optionally, the PDU session modification request message may further include a QoS parameter.

It should be noted that the AM PCF and the SM PCF may be the same PCF functional entity, or may be different PCF functional entities, which is not limited in this application.

S709, the SM PCF sends a data query request message to the UDR.

S710, the UDR sends the background data transmission policy to the SM PCF.

For example, if the SM PCF determines that the current service is a background data transfer service according to the policy association creation request message, the SM PCF sends a data query request message to the UDR, where the data query request message may include SUPI and DNN, and further may include S-NSSAI. And the UDR searches a corresponding background data transmission strategy according to the data query request message and sends the background data transmission strategy to the SM PCF.

For another example, if the SM PCF determines that the current service is a background data transfer service according to the policy association modification request message, then sends a data query request message to the UDR, where the data query request message may include the service data flow description information, the SUPI, and the DNN, and further may include the S-NSSAI. And the UDR searches a corresponding background data transmission strategy according to the data query request message and sends the background data transmission strategy to the SM PCF. S711, the SM PCF executes policy decision according to the information of the rate, the bandwidth and the like in the background data transmission policy and the subscription information.

The prior art can be referred to how the SM PCF makes policy decision according to the background data transmission policy obtained from the UDR, and details are not described herein.

It should be noted that S709 to S711 may not depend on S703 to S707. For example, the operations before S709 may be performed according to the prior art. It should be noted that the AM PCF may refer to the three manners described above for storing the negotiated background data transmission policy in the UDR.

According to the method provided by the application, the AM PCF can acquire each time window information and the transmission indication information corresponding to each time window information from the background data transmission strategy negotiation request message sent by the AF, and the AM PCF can provide each time window information and the corresponding transmission indication information to the UE through the user routing strategy, so that the UE can trigger the PDU session establishment or modification flow according to the transmission type of the background data transmission capable of being carried out in each time window, thereby more reasonably using the network resources and solving the problem of wasting the network resources in the prior art. On the other hand, the SM PCF can acquire the corresponding background data transmission strategy from the UDR based on the DNN corresponding to the PDU session initiated by the UE or the DNN and the service flow description information, and the method does not need AF to send the background data transmission strategy authorization request message, thereby saving the signaling overhead.

Fig. 8 shows a schematic flow chart of a method 800 for background data transmission according to an embodiment of the application. In the method 800, the UDR may provide the at least one time window information and the at least one transmission indication information to the AM PCF. The steps shown in fig. 8 will be explained below.

S801, the UDR sends a background data transmission strategy to the AM PCF. Accordingly, the AM PCF receives the background data transmission policy sent by the UDR.

Before S801, the AF has already negotiated a background data transmission policy with the PCF that performed the background data transmission policy negotiation, and the background data transmission policy is stored in the UDR, which can provide the background data transmission policy to the AM PCF. Wherein the context data transmission policy includes the at least one time window information and the at least one transmission indication information. Optionally, the background data transmission policy may further include the at least one network area information.

Thereafter, the cells perform S802 to S810 accordingly.

S802 to S810 may refer to S703 to S711, which are not described herein.

According to the method provided by the application, the UDR can provide transmission indication information corresponding to each time window information of an AF (Ad hoc network) carrier to the AM PCF, and the AM PCF can provide each time window information and the corresponding transmission indication information to the UE through a user routing strategy, so that the UE can trigger PDU (protocol data Unit) session establishment or modification flow according to the transmission type of background data transmission capable of being carried out in each time window, network resources can be used more reasonably, and the problem of network resource waste in the prior art is solved. On the other hand, the SM PCF can acquire the corresponding background data transmission strategy from the UDR based on the DNN corresponding to the PDU session initiated by the UE or the DNN and the service flow description information, and the method does not need AF to send the background data transmission strategy authorization request message, thereby saving the signaling overhead.

Having described the method of transmitting a terminal policy according to an embodiment of the present application, an apparatus according to an embodiment of the present application will be described below.

Fig. 9 shows a schematic block diagram of a communication device 900 according to an embodiment of the application. The communication device may include a transceiving unit 910 and a processing unit 920.

The communication apparatus 900 may be any network element related to the present application, and may implement the functions that can be implemented by the network element. It is understood that the communication apparatus 900 may be a physical device, a component (e.g., an integrated circuit, a chip, etc.) of the physical device, or a functional module in the physical device.

In one implementation, the transceiving unit 910 is configured to receive a user routing policy, where the user routing policy includes at least one time window information and at least one transmission indication information, where the at least one time window information corresponds to the at least one transmission indication information in a one-to-one manner, the first transmission indication information is used to indicate a transmission type of background data transmission that can be performed in a first time window indicated by the first time window information, the first time window corresponds to the first transmission indication information, the first transmission indication information is any one of the at least one transmission indication information, and the first time window information is any one of the at least one time window information; a processing unit 920, configured to trigger a protocol data unit PDU session establishment or a modification procedure within the first time window according to the first transmission indication information, so as to perform background data transmission within the first time window.

Optionally, the processing unit 920 is specifically configured to: if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is uplink transmission, triggering PDU session establishment or a PDU session modification process when the need of initiating the background data transmission is determined in the first time window.

Optionally, the processing unit 920 is specifically configured to: and if the first transmission indication information indicates that the transmission type of the background data transmission capable of being carried out in the first time window is downlink transmission, triggering PDU session establishment or a PDU session modification process when the first time window begins.

Optionally, the user routing policy further includes at least one network area information, the at least one network area information corresponds to the at least one time window information and the at least one transmission indication information one to one, and a first network area indicated by a first network area information in the at least one network area information corresponds to the first time window and the first transmission indication information. And, the processing unit 920 is specifically configured to: and triggering a PDU session establishment or modification process within the first time window according to the first transmission indication information under the condition that the device is located in the first network area.

In one implementation, the transceiving unit 910 is configured to receive a policy association creation request message, where the policy association creation request message includes data network names DNN and DNN; sending a data query request message to the UDR, the data query request message including the DNN and the SUPI, the data query request message for requesting a background data transfer policy; and receiving a background data transmission strategy corresponding to the DNN and the SUPI sent by the UDR.

Optionally, the policy association creation request message further includes an S-NSSAI. And the data query request message further includes the S-NSSAI, the S-NSSAI corresponding to the background data transmission policy.

In another implementation, the transceiving unit 910 is configured to receive a policy association update request message, where the policy association update request message includes service data flow description information and SUPI; transmitting a data query request message including the description information, the SUPI, and a data network name DNN to the UDR, the data query request for requesting a background data transfer policy; and receiving a background data transmission policy sent by the UDR, wherein the background data transmission policy corresponds to the service data flow description information, the SUPI and the DNN.

Optionally, the data query request message further includes an S-NSSAI, and the S-NSSAI corresponds to the background data transmission policy.

It should be understood that in the present embodiment, the communication apparatus 900 is presented in the form of a functional module. As used herein, a "module" may refer to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that may provide the described functionality. In a simple embodiment, those skilled in the art will appreciate that the apparatus 900 may take the form shown in FIG. 6. The processing unit 920 may be implemented by the processor 601 shown in fig. 6. Alternatively, if the apparatus shown in fig. 6 includes the memory 602, the processing module 920 may be implemented by the processor 601 and the memory 602. The transceiving unit 910 may be implemented by the transceiver 605 shown in fig. 6. In particular, the processor is implemented by executing a computer program stored in the memory. Alternatively, when the apparatus 900 is a chip, the functions and/or implementation processes of the transceiver module 910 can also be implemented by pins or circuits. Alternatively, the memory may be a storage unit in the chip, such as a register, a cache, or the like, and the storage unit may also be a storage unit in the computer device that is located outside the chip, such as the memory 602 shown in fig. 6, or may also be a storage unit disposed in another system or device, which is not in the computer device.

It should be understood that the processor in the embodiments of the present application may be an integrated circuit chip having signal processing capability. In implementation, the steps of the above method embodiments may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The processor may be a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic device, or discrete hardware components.

It will be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM, enhanced SDRAM, SLDRAM, Synchronous Link DRAM (SLDRAM), and direct rambus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

The present application also provides a computer-readable medium having stored thereon a computer program which, when executed by a computer, performs the functions of any of the method embodiments described above.

The present application also provides a computer program product which, when executed by a computer, implements the functionality of any of the above-described method embodiments.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a Digital Video Disk (DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), among others.

It should be appreciated that reference throughout this specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, the various embodiments are not necessarily referring to the same embodiment throughout the specification. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. It should be understood that, in the various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

It should also be understood that, in the present application, "when …", "if" and "if" all refer to the fact that the UE or the base station will perform the corresponding processing under certain objective conditions, and are not limited time, and do not require the UE or the base station to perform certain judgment actions, nor do they mean that there are other limitations.

Additionally, the terms "system" and "network" are often used interchangeably herein. The term "and/or" herein is merely an association describing an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. "A/B" is described herein, and means A or B except SAC/AS. Herein, the term "at least one of … …" or "at least one of … …" means all or any combination of the listed items, e.g., "at least one of A, B and C", may mean: there are six cases of a alone, B alone, C alone, a and B together, B and C together, and A, B and C together.

It should be understood that in the embodiments of the present application, "B corresponding to a" means that B is associated with a, from which B can be determined. It should also be understood that determining B from a does not mean determining B from a alone, but may be determined from a and/or other information.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for background data transmission, comprising:

a terminal device receives a user routing strategy, wherein the user routing strategy comprises at least one time window information and at least one transmission indication information, the at least one time window information corresponds to the at least one transmission indication information one to one, the first transmission indication information is used for indicating a transmission type of background data transmission capable of being carried out in a first time window indicated by the first time window information, the first time window corresponds to the first transmission indication information, the first transmission indication information is any one of the at least one transmission indication information, and the first time window information is any one of the at least one time window information;

and the terminal equipment triggers a Protocol Data Unit (PDU) session establishment or modification flow in the first time window according to the first transmission indication information so as to transmit background data in the first time window.

2. The method of claim 1, wherein the triggering, by the terminal device, a PDU session establishment or modification procedure within the first time window according to the first transmission indication information comprises:

if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is uplink transmission, triggering PDU session establishment or a PDU session modification flow when the terminal device determines that the background data transmission needs to be initiated in the first time window.

3. The method according to claim 1 or 2, wherein the triggering, by the terminal device, a PDU session establishment or modification procedure within the first time window according to the first transmission indication information comprises:

and if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is downlink transmission, the terminal equipment triggers PDU session establishment or a PDU modification flow when the first time window begins.

4. The method according to any of claims 1 to 3, wherein the user routing policy further comprises at least one network area information, the at least one network area information corresponding one-to-one to the at least one time window information and the at least one transmission indication information, a first network area indicated by a first network area information of the at least one network area information corresponding to the first time window and the first transmission indication information;

5. A communications apparatus, comprising:

a receiving and sending unit, configured to receive a user routing policy, where the user routing policy includes at least one time window information and at least one transmission indication information, where the at least one time window information corresponds to the at least one transmission indication information one to one, the first transmission indication information is used to indicate a transmission type of background data transmission that can be performed in a first time window indicated by the first time window information, the first time window corresponds to the first transmission indication information, the first transmission indication information is any one of the at least one transmission indication information, and the first time window information is any one of the at least one time window information;

and the processing unit is used for triggering Protocol Data Unit (PDU) session establishment or flow modification in the first time window according to the first transmission indication information so as to transmit background data in the first time window.

6. The apparatus as claimed in claim 5, wherein said processing unit is specifically configured to:

and if the first transmission indication information indicates that the transmission type of the background data transmission capable of being carried out in the first time window is uplink transmission, triggering PDU session establishment or flow modification when the background data transmission needs to be initiated in the first time window.

7. The apparatus according to claim 5 or 6, wherein the processing unit is specifically configured to:

and if the first transmission indication information indicates that the transmission type of the background data transmission capable of being carried out in the first time window is downlink transmission, triggering PDU session establishment or flow modification when the first time window begins.

8. The method according to any of claims 5 to 7, wherein the user routing policy further comprises at least one network area information, the at least one network area information corresponding one-to-one to the at least one time window information and the at least one transmission indication information, a first network area indicated by a first network area information of the at least one network area information corresponding to the first time window and the first transmission indication information;

and the processing unit is specifically configured to:

and under the condition that the device is positioned in the first network area, triggering PDU session establishment or modification flow in the first time window according to the first transmission indication information.

9. A communication system, comprising:

the terminal equipment and the first strategy control function network element;

the first policy control function network element is configured to obtain at least one time window information and at least one transmission indication information, and send a user routing policy to the terminal device, where the user routing policy includes the at least one time window information and the at least one transmission indication information, the at least one time window information corresponds to the at least one transmission indication information one to one, the first transmission indication information is used to indicate a transmission type of background data transmission that can be performed in a first time window indicated by the first time window information, the first time window corresponds to the first transmission indication information, the first transmission indication information is any one of the at least one transmission indication information, and the first time window information is any one of the at least one time window information;

10. The system of claim 9, wherein the system further comprises a first unified data repository, UDR;

11. The system of claim 9, wherein the system further comprises an application function network element;

12. The system according to any of claims 9 to 11, wherein the terminal device is configured to trigger a PDU session establishment or modification procedure within the first time window according to the first transmission indication information, and includes:

if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is uplink transmission, the terminal device is configured to trigger PDU session establishment or a PDU session modification procedure when it is determined that the background data transmission needs to be initiated in the first time window.

13. The system according to any of claims 9 to 12, wherein the terminal device is configured to trigger a PDU session establishment or modification procedure within the first time window according to the first transmission indication information, and includes:

and if the first transmission indication information indicates that the transmission type of the background data transmission capable of being performed in the first time window is downlink transmission, the terminal device is configured to trigger a PDU session establishment or a PDU session modification process when the first time window starts.

14. The system according to any of claims 9 to 13, wherein the user routing policy further comprises at least one network area information, the at least one network area information corresponding one-to-one to the at least one time window information and the at least one transmission indication information, a first network area indicated by a first network area information of the at least one network area information corresponding to the first time window and the first transmission indication information;

15. The system according to any of the claims 9 to 14, wherein the system further comprises a session management function network element, a second policy control function network element and a second unified data repository, UDR;

16. The system according to any of the claims 9 to 14, wherein the system further comprises a session management function network element, a second policy control function network element and a second unified data repository, UDR;

and the terminal device is configured to trigger a PDU session modification procedure within the first time window according to the first transmission indication information, including:

the terminal equipment is used for sending a PDU session modification request message to the session management function network element according to the first transmission indication information, wherein the PDU session modification request message comprises service data flow description information and a user permanent identity (SUPI); the session management function network element is used for receiving the PDU session modification request message; sending a policy association update request message to the second policy control function network element, the policy association update request message including the service data flow description information and the SUPI;

the second policy control function network element is configured to receive the policy association update request message; sending a data query request message to the second UDR, the data query request message including the service data flow description information, the user permanent identity, SUPI, and a data network name, DNN, the data query request message requesting a background data transfer policy, the background data transfer policy corresponding to the DNN, the SUPI, and the service data flow description information;

the second UDR is used for receiving the data query request message; and sending the background data transmission strategy to the second strategy control function network element according to the data query request message.