Method, device and system for formulating background data transmission strategy

Abstract

The embodiments of the present application disclose a method, apparatus, and system for formulating a background data transmission policy. The method includes: a first policy control network element sends a first message to a first network element for requesting a background data transmission policy stored by the first network element; obtaining from the first network element the background data transmission policy stored by the first network element and second decision information for formulating a second background data transmission policy; and the first policy control network element formulates the first background data transmission policy based on the first decision information for formulating the first background data transmission policy, the second decision information, and the background data transmission policy stored by the first network element. The present application solution can be used in the fields of communication technology, artificial intelligence, Internet of Vehicles, smart home networking, and the like.

Description

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on June 3, 2020, with application number 202010496925.5 and application name “Method, device and system for formulating background data transmission strategy”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present application relate to the field of communication technology, and in particular to a method, device, and system for formulating a background data transmission strategy. Background Art

[0003] In the 3rd Generation Partnership Project (3GPP) communication system, network-side equipment provides policy control, application detection and service awareness, billing control, usage control, and traffic steering for user service access. It also provides quality of service (QoS) assurance, sponsored data services, and background data transmission policy negotiation for third-party applications.

[0004] In the process of providing background data transmission policy negotiation function for third-party applications by network-side devices, the network-side devices obtain all existing background data transmission policies, determine candidate background data transmission policies based on all the background data transmission policies and other information, and the third-party application server selects a background data transmission policy from the candidate background data transmission policies as its own background data transmission policy to perform background data transmission. This background data transmission policy negotiation method does not take into account the background data transmission policies being formulated by other network-side devices for other third-party application servers, resulting in the formulated background data transmission policies being suboptimal, affecting the normal transmission of background data. In addition, when executing policies according to the background data transmission policy, the network-side devices do not consider that the background data transmission policy may be being modified by other network-side devices, resulting in errors in the execution of the background data transmission policy. Summary of the Invention

[0005] The embodiments of the present application provide a method, device, and system for formulating a background data transmission policy, which solve the problem of conflicts among multiple policy control network elements when formulating background data transmission policies.

[0006] To achieve the above objectives, the present invention adopts the following technical solutions:

[0007] In a first aspect, an embodiment of the present application provides a method for formulating a background data transmission strategy, which may include: a first policy control network element sends a first message to a first network element for requesting the background data transmission strategy saved by the first network element, obtains from the first network element the background data transmission strategy saved by the first network element and second decision information for formulating a second background data transmission strategy, and formulates a first background data transmission strategy based on the first decision information used to formulate the first background data transmission strategy, the second decision information, and the background data transmission strategy saved by the first network element.

[0008] Based on the first aspect, when formulating the background data transmission strategy, the policy control network element refers to the existing background data transmission strategy and the decision information corresponding to the background data transmission strategy being formulated by other policy control network elements, so as to avoid conflicts between the formulated background data transmission strategy and the background data transmission strategy formulated by other policy control network elements, thereby ensuring the availability of the background data transmission strategy.

[0009] In one possible design, the first decision information includes one or more of the following: the number of first terminals, the first time window, the first network area information, the first traffic volume when each terminal transmits background data, or the reason for formulating the first background data transmission policy; the second decision information includes one or more of the following: the number of second terminals, the second time window, the second network area information, the second traffic volume when each terminal transmits background data, or the reason for formulating the second background data transmission policy. Based on this possible design, one or more pieces of decision information can be provided to the policy control network element, thereby improving the accuracy of the background data transmission policy formulated by the policy control network element based on this policy information.

[0010] In one possible design, the second decision information includes one or more of the following: the number of second terminals, a second time window, second network area information, a second traffic volume when each terminal transmits background data, an indication that a second background data transmission policy is being negotiated, or a reason for formulating the second background data transmission policy. Based on this possible design, one or more pieces of decision information can be provided to the policy control network element, thereby improving the accuracy of the policy control network element in formulating the background data transmission policy based on this policy information.

[0011] In one possible design, the first policy control network element formulates the first background data transmission strategy based on the first decision information, the second decision information, and the background data transmission strategy saved by the first network element, including: when it is determined that the second decision information affects the formulation of the first background data transmission strategy, the first policy control network element formulates the first background data transmission strategy based on the first decision information, the second decision information, and the background data transmission strategy saved by the first network element, and the execution of the first background data transmission strategy and the second background data transmission strategy do not affect each other. Based on this possible design, when the second decision information affects the formulation of the first background data transmission strategy, the first policy control network element does not delay the formulation of the first background data transmission strategy, but continues to formulate the first background data transmission strategy based on all acquired background data transmission strategies and the first decision information, that is, formulates it in parallel with the second background data transmission strategy, thereby improving the formulation speed of background data transmission. At the same time, in order to avoid conflicts between the first background data transmission strategy and the second background data transmission strategy, it is required that the execution of the first background data transmission strategy and the second background data transmission strategy do not affect each other, thereby avoiding network congestion and ensuring the normal transmission of background data.

[0012] In one possible design, the first policy control network element formulates the first background data transmission strategy based on the first decision information, the second decision information, and the background data transmission strategy saved by the first network element, including: when it is determined that the second decision information affects the formulation of the first background data transmission strategy, the first policy control network element obtains the second background data transmission strategy and then formulates the first background data transmission strategy based on the first decision information, the background data transmission strategy saved by the first network element, and the second background data transmission strategy. Based on this possible design, when the second decision information affects the formulation of the first background data transmission strategy, the first policy control network element delays the formulation of the first background data transmission strategy, first formulates the second background data transmission strategy, and then formulates the first background data transmission strategy in combination with all the formulated background data transmission strategies, so as to avoid conflicts between the first background data transmission strategy and the second background data transmission strategy and ensure the normal transmission of background data.

[0013] In one possible design, the first policy control network element formulates the first background data transmission strategy based on the first decision information, the second decision information and the background data transmission strategy saved by the first network element, including: the first policy control network element delays the formulation of the first background data transmission strategy, and after obtaining the second background data transmission strategy, formulates the first background data transmission strategy based on the first decision information and the background data transmission strategy saved by the first network element.

[0014] Based on this possible design, the first policy control network element delays the formulation of the first background data transmission strategy. After the second background data transmission strategy is formulated, the first background data transmission strategy is formulated in combination with all the formulated background data transmission strategies (including the second background data transmission strategy) to avoid conflicts between the first background data transmission strategy and the second background data transmission strategy, thereby ensuring the normal transmission of background data.

[0015] In one possible design, the first policy control network element formulates the first background data transmission strategy based on the first decision information, the second decision information and the background data transmission strategy saved by the first network element, including: the first policy control network element delays the formulation of the first background data transmission strategy, and after obtaining the deletion indication corresponding to the second decision information, formulates the first background data transmission strategy based on the first decision information and the background data transmission strategy saved by the first network element.

[0016] Based on this possible design, when the first policy control network element refers to the second decision information to formulate the first background data transmission policy, if a deletion indication corresponding to the second decision information is received, the second decision information or the background data transmission policy corresponding to the second decision information is deleted, and the first background data transmission policy is no longer formulated with reference to the second decision information or the background data transmission policy corresponding to the second decision information, thereby improving the accuracy of the formulation of the first background data transmission policy and timely deleting unavailable / invalid background data transmission policies, thereby improving resource utilization.

[0017] In one possible design, the second decision information affects the formulation of the first background data transmission strategy, including one or more of the following situations: the first time window overlaps with the second time window, and the network area indicated by the first network area information overlaps with the network area indicated by the second network area information. Based on this possible design, whether the first decision information affects the formulation of the first background data transmission strategy can be determined based on whether the transmission time windows corresponding to the background data overlap and / or whether the network areas to which the background data transmission strategy is applicable overlap, thereby avoiding the formulation of multiple background data transmission strategies in the same time window and / or the same network area, and adopting multiple background data transmission strategies to transmit a large amount of background data, thereby ensuring the normal transmission of background data.

[0018] In one possible design, the first message includes a first reference identifier and first decision information, and the first reference identifier is used to identify the first background data transmission strategy. Based on this possible design, the first policy control network element can send the first decision information to the first network element so that the first network element can save the first decision information, and during the period when the first background data transmission strategy is formulated according to the first decision information, when other policy control network elements formulate background data transmission strategies, the first decision information is sent to other policy control network elements so that other policy control network elements can refer to the first decision information to formulate their own background data transmission strategies, thereby avoiding conflicts between different background data transmission strategies, affecting the availability of background data transmission strategies, and causing network congestion.

[0019] In one possible design, before the first policy control network element sends the first message to the first network element, the method further includes: the first policy control network element receiving a second message including first decision information from the first application server, where the second message is used to request the first policy control network element to formulate a first background data transmission policy. Based on this possible design, the first policy control network element obtains the first decision information from the first application server, i.e., the application server sends the user's background data transmission requirements, etc. to the policy control network element, eliminating the need for the user to send the information to the policy control network element through multiple network elements, thereby reducing signaling overhead.

[0020] In one possible design, the method further includes: when the network performance indicator is lower than or restored to a preset threshold, the first policy control network element sends a first message to the first network element, the network performance indicator event is an event in which the network performance indicator is lower than or restored to the preset threshold during the third background data transmission strategy time window, and the third background data transmission strategy is a background data transmission strategy formulated according to the first decision information. Based on this possible design, when the network performance indicator is lower than or restored to the preset threshold when background data is transmitted using the background data transmission strategy, that is, when the network status changes, the first message can be sent to the first network element in a timely manner to obtain the formulated background data transmission strategy, and the currently used background data transmission strategy can be adaptively adjusted according to the formulated background data transmission strategy, so that the currently used background data transmission strategy meets the network transmission requirements and improves the usability of the background data transmission strategy.

[0021] In one possible design, the method further includes: the first policy control network element sends a subscription request to the NWDAF for obtaining network performance indicator events, and receives network performance indicator events notified by the NWDAF. Based on this possible design, the first policy control network element can learn from the NWDAF that the network performance indicator is lower than or restored to a preset threshold, that is, the NWDAF analyzes whether the network performance indicator is lower than or restored to the preset threshold and notifies the first policy control network element, thereby reducing the power consumption of the first policy control network element in determining whether the network performance indicator is lower than or restored to the preset threshold.

[0022] In one possible design, the first network element includes a unified data management (UDM) network element, a network repository function (NRF) network element, or a unified data repository (UDR) network element. Based on this possible design, information such as background data transmission strategies can be stored by multiple different network elements, such as the UDM network element, the NRF network element, or the UDR network element, thereby improving system design flexibility.

[0023] In one possible design, the method further includes: the first policy control network element sends a third message including a first reference identifier and first decision information to the first network element, where the first reference identifier is used to identify the first background data transmission policy.

[0024] Based on this possible design, the first policy control network element can carry the first reference identifier and the first decision information in a third message and send it to the first network element, so that the first network element can save the first decision information, and during the period when the first background data transmission strategy is formulated according to the first decision information, when other policy control network elements formulate background data transmission strategies, the first decision information will be sent to other policy control network elements, so that other policy control network elements can refer to the first decision information to formulate their own background data transmission strategies, thereby avoiding conflicts between different background data transmission strategies, affecting the availability of background data transmission strategies, and causing network congestion.

[0025] In the second aspect, an embodiment of the present application also provides a method for formulating a background data transmission strategy, the method including: a first network element receives second decision information from a second policy control network element, the second decision information corresponds to a second background data transmission strategy; the first network element receives a first message from a first policy control network element, the first message is used to request the background data transmission strategy saved by the first network element; the first network element sends the background data transmission strategy saved by the first network element and the second decision information to the first policy control network element; the second decision information and the background data transmission strategy saved by the first network element are used to formulate the first background data transmission strategy.

[0026] Based on the second aspect, the first network element sends the saved background data transmission strategy and the decision information corresponding to the background data transmission strategy being negotiated to the first policy control network element that is to formulate the background data transmission strategy, so that when the first policy control network element formulates the background data transmission strategy, it can refer to the existing background data transmission strategy and the decision information corresponding to the background data transmission strategy being formulated by other policy control network elements, thereby avoiding conflicts between the formulated background data transmission strategy and the background data transmission strategy formulated by other policy control network elements, and ensuring the availability of the background data transmission strategy.

[0027] In one possible design, the method further includes: the first network element receiving a second background data transmission policy from a second policy control network element; the first network element sending the second background data transmission policy to the first policy control network element, and the second background data transmission policy is used to formulate the first background data transmission policy.

[0028] Based on this possible design, the successfully negotiated background data transmission policy can be sent to the first policy control network element so that the first policy control network element can formulate its own background data transmission policy based on the successfully negotiated background data transmission policy to avoid conflicts between different background data transmission policies.

[0029] In one possible design, the method also includes: the first network element receives a deletion indication corresponding to the second decision information from the second policy control network element; the first network element deletes the second decision information according to the deletion indication; the first network element sends a deletion indication corresponding to the second decision information to the first policy control network element, and the deletion indication is used to instruct the first policy control network element to delete the second decision information.

[0030] Based on this possible design, the second decision information or the background data transmission strategy corresponding to the second decision information can be deleted when the second decision information or the background data transmission strategy corresponding to the second decision information is invalid / unavailable, so that the first policy control network element deletes the acquired second decision information and / or the background data transmission strategy corresponding to the second decision information according to the deletion instruction sent by the first network element, and no longer refers to the second decision information and / or the background data transmission strategy corresponding to the second decision information when formulating its own background data transmission strategy, thereby improving the accuracy of background data transmission strategy formulation and improving resource utilization.

[0031] Among them, the relevant description of the second decision information described in the second aspect or the possible design of the second aspect can be referred to in the first aspect or the possible design of the first aspect, and will not be repeated here.

[0032] In a third aspect, an embodiment of the present application also provides a method for session management, the method comprising: a second policy control network element receives a policy-associated establishment request corresponding to a session establishment request of a user equipment UE, sends a fourth message to a first network element for requesting a first background data transmission policy applied to the session, obtains first decision information corresponding to the first background data transmission policy from the first network element, and manages the session according to the first decision information.

[0033] Based on the method described in the third aspect, when the policy control network element formulates the session management policy for the UE's session, it can obtain the decision information required to formulate the UE's session management policy from the first network element, and manage the session with reference to the obtained decision information, thereby avoiding the problem of conflict between the background data transmission policy corresponding to the formulated decision information and the UE's session, and ensuring the availability of the background data transmission policy and the UE's session.

[0034] In one possible design, the second policy control network element manages the session according to the first decision information, including: the second policy control network element rejects the request to establish a policy association according to the first decision information.

[0035] Based on this possible design, when the first decision information affects the formulation of the first strategy, the request to establish the policy association is rejected, and the formulation of the session management strategy and the establishment of the PDU session are stopped to avoid conflicts between the session management strategy and the background data transmission strategy corresponding to the first decision information, thereby ensuring the normal transmission of background data.

[0036] In one possible design, the second policy control network element manages the session according to the first decision information, including: the second policy control network element accepts a request to establish a policy association according to the first decision information.

[0037] Based on this possible design, a request to establish a policy association is accepted, and a session management policy for the session is formulated based on the background data transmission policy corresponding to the first decision information to ensure normal transmission of background data.

[0038] In one possible design, the method also includes: after the second policy control network element receives the first background data transmission policy corresponding to the first decision information sent by the first network element, it formulates a session management policy for the session for performing policy billing control on the session based on the first background data transmission policy, and sends the session management policy for the session to the session management network element.

[0039] Based on this possible design, the second strategy controls the network element to delay the formulation of the first strategy. After the formulation of the first background data transmission strategy is completed, the session management strategy is formulated in combination with all the formulated background data transmission strategies (including the first background data transmission strategy) to establish a session, thereby avoiding conflicts between the first background data transmission strategy and the session management strategy and ensuring the normal transmission of background data.

[0040] In one possible design, the method further includes: after the second policy control network element receives the first background data transmission policy sent by the first network element, terminating the policy association according to the first background data transmission policy.

[0041] Based on this possible design, after the second policy control network element formulates the first background data transmission policy, if the first background data transmission policy conflicts with the session management policy, the policy association is terminated according to the first background data transmission policy to avoid the conflict between the first background data transmission policy and the session management policy, thereby ensuring the normal transmission of background data.

[0042] In one possible design, the method also includes: the second policy control network element terminates the policy association after receiving a deletion indication corresponding to the first decision information.

[0043] Based on this possible design, the second policy control network element receives a deletion indication corresponding to the first decision information, determines that the first background data transmission policy is unavailable / invalid, and there is no first background data transmission policy associated with the session management policy, then terminates the policy association to avoid the background data transmission failure caused by the invalid session of the designated terminal.

[0044] Among them, the relevant description of the first decision information described in the third aspect or the possible design of the third aspect can be referred to in the first aspect or the possible design of the first aspect, and will not be repeated here.

[0045] In one possible design, the fourth message includes a first reference identifier. The relevant description of the first reference identifier can be referred to in the first aspect or the possible design of the first aspect and will not be repeated here.

[0046] In fourth aspect, an embodiment of the present application also provides a UE policy management method, which includes: a second policy control network element receives a request to establish a policy association corresponding to a registration request of a user device, sends a fourth message to a first network element, the fourth message is used to request a first background data transmission policy applied to the UE, obtains first decision information from the first network element, the first decision information corresponds to the first background data transmission policy, and formulates a UE policy for the UE based on the first decision information.

[0047] Based on the method described in the fourth aspect, when formulating the UE policy of the UE, the policy control network element can obtain the decision information required to formulate the UE policy of the UE from the first network element, and manage the session with reference to the obtained decision information to avoid the problem of conflict between the background data transmission policy corresponding to the formulated decision information and the UE, thereby ensuring the availability of the background data transmission policy and the UE policy of the UE.

[0048] In one possible design, the second policy control network element formulates the UE policy of the UE based on the first decision information, including: the second policy control network element delays formulating the UE policy of the UE, and after obtaining the first background data transmission strategy corresponding to the first decision information, formulates the UE policy of the UE based on the first background data transmission strategy.

[0049] Based on this possible design, when the first decision information affects the formulation of the UE policy of the UE, the formulation of the UE policy of the UE is delayed. After obtaining the first background data transmission strategy corresponding to the first decision information, the UE strategy is formulated based on the background data transmission strategy corresponding to the first decision information to ensure the normal transmission of background data.

[0050] In one possible design, the method also includes: the second policy control network element sends a policy association establishment response, and the policy association establishment response does not carry the UE policy of the UE.

[0051] Among them, the relevant description of the first decision information described in the fourth aspect or the possible design of the fourth aspect can be referred to in the first aspect or the possible design of the first aspect, and will not be repeated here.

[0052] In one possible design, the fourth message includes a first reference identifier. The relevant description of the first reference identifier can be referred to in the first aspect or the possible design of the first aspect and will not be repeated here.

[0053] In a fifth aspect, the present application provides a communication device, which may be a first policy control network element or a chip or system on chip in the first policy control network element, or a module or unit in the first policy control network element for implementing the method for formulating background data transmission policy described in the embodiment of the present application, or other modules or units capable of implementing the method executed by the first policy control network element. The communication device can implement the functions performed by the first policy control network element in the above-mentioned first aspect or each possible design. In one design, the communication device may include a module unit or means corresponding to the method / operation / step / action described in the first aspect, and the module, unit, or means may be implemented by hardware, software, or by hardware executing the corresponding software implementation. The hardware or software includes one or more modules or units corresponding to the above-mentioned functions. For example, the communication device may include: a sending unit, a receiving unit, and a processing unit;

[0054] The sending unit is configured to send a first message to the first network element, where the first message is used to request the background data transmission policy saved by the first network element.

[0055] The receiving unit is configured to obtain, from the first network element, the background data transmission strategy and second decision information stored in the first network element, where the second decision information is used to formulate a second background data transmission strategy.

[0056] The processing unit is configured to formulate a first background data transmission strategy based on the first decision information, the second decision information and the background data transmission strategy stored in the first network element, wherein the first decision information is used to formulate the first background data transmission strategy.

[0057] The relevant definitions of the first decision information and the second decision information and the manner in which the processing unit formulates the first background data transmission strategy may refer to the first aspect or the possible design of the first aspect and will not be elaborated on herein.

[0058] The specific implementation of the communication device can refer to the behavior function of the terminal in the data transmission method provided in the first aspect or any possible design of the first aspect, and will not be repeated here. Therefore, the provided communication device can achieve the same beneficial effects as the first aspect or any possible design of the first aspect.

[0059] In another possible design, the communication device described in the fifth aspect can be a first network element or a chip or system on chip in the first network element, or a module or unit in the first network element for implementing the method for formulating a background data transmission strategy described in an embodiment of the present application, or other modules or units that can implement the method executed by the first network element. The communication device can implement the functions performed by the first network element in the above-mentioned second aspect or the possible design of the second aspect. For example, the communication device may include a module unit or means corresponding to the method / operation / step / action described in the second aspect, and the module, unit, or means can be implemented by hardware, software, or by hardware executing the corresponding software implementation. The hardware or software includes one or more modules or units corresponding to the above-mentioned functions.

[0060] For example, the communication device can be used to receive second decision information from a second policy control network element, the second decision information corresponds to a second background data transmission strategy, receive a first message from a first policy control network element, the first message is used to request the background data transmission strategy saved by the first network element, and send the background data transmission strategy saved by the first network element and the second decision information to the first policy control network element; the second decision information and the background data transmission strategy saved by the first network element are used to formulate the first background data transmission strategy.

[0061] In another possible design, the communication device described in the fifth aspect may be a second policy control network element or a chip or system on chip in the second policy control network element, or a module or unit in the second policy control network element for implementing the session management method described in the embodiment of the present application, or other modules or units capable of implementing the method executed by the second policy control network element. The communication device can implement the functions performed by the second policy control network element in the above-mentioned third aspect or each possible design of the third aspect. In one design, the communication device may include a module unit or means corresponding to the method / operation / step / action described in the third aspect, and the module, unit, or means may be implemented by hardware, software, or by hardware executing the corresponding software implementation. The hardware or software includes one or more modules or units corresponding to the above-mentioned functions.

[0062] For example, the communication device is used to receive a policy-associated establishment request corresponding to a session establishment request of a user equipment UE, send a fourth message to the first network element for requesting a first background data transmission policy applied to the session, obtain first decision information corresponding to the first background data transmission policy from the first network element, and manage the session according to the first decision information.

[0063] For another example, the communication device is used to receive a request to establish a policy association corresponding to a registration request of a user equipment, send a fourth message to the first network element for requesting a first background data transmission policy applied to the UE, obtain first decision information from the first network element, the first decision information corresponds to the first background data transmission policy, and formulate a UE policy for the UE based on the first decision information.

[0064] In a sixth aspect, a communication device is provided, which may be a first policy control network element or a chip or system on chip in the first policy control network element, or other modules or units capable of implementing the method on the first policy control network element side. The communication device may implement the functions performed by the first policy control network element in the above-mentioned first aspect or each possible design, and the functions may be implemented by hardware. In one possible design, the communication device may include: a processor and a communication interface, the processor being configured to send a first message for requesting a background data transmission policy saved by the first network element to the first network element through the communication interface, obtain the background data transmission policy saved by the first network element and second decision information for formulating a second background data transmission policy from the first network element, and formulate the first background data transmission policy based on the first decision information for formulating the first background data transmission policy, the second decision information, and the background data transmission policy saved by the first network element.

[0065] In another possible design, the communication device described in the sixth aspect may be a first network element or a chip or system on chip in the first network element, or may be a module or unit in the first network element for implementing the method for formulating a background data transmission strategy described in an embodiment of the present application, or other modules or units capable of implementing the method executed by the first network element, such as the communication device may include: a processor and a communication interface. The processor and communication interface included in the communication device are used to support the communication device in implementing the functions performed by the first network element in the above-mentioned second aspect or each possible design of the second aspect.

[0066] In another possible design, the communication device described in the sixth aspect may be a second policy control network element or a chip or system on chip in the second policy control network element, or may be a module or unit in the second policy control network element for implementing the session management method described in the embodiment of the present application, or other modules or units capable of implementing the method executed by the second policy control network element, such as the communication device may include: a processor and a communication interface. The processor and communication interface included in the communication device are used to support the communication device in implementing the functions performed by the second policy control network element in the third aspect or each possible design of the third aspect, or to implement the functions performed by the second policy control network element in the fourth aspect or each possible design of the fourth aspect.

[0067] In another possible design, the communication device of the sixth aspect may further include a memory, which is used to store computer instructions and / or data. When the communication device is running, the processor executes the computer instructions stored in the memory, so that the communication device executes the method for formulating a background data transmission strategy described in the first aspect or any possible design of the first aspect; or, executes the method for formulating a background data transmission strategy described in the second aspect or any possible design of the second aspect; or, executes the session management method described in the third aspect or any possible design of the third aspect; or, executes the UE policy management method described in the fourth aspect or any possible design of the fourth aspect. In an embodiment of the present application, the communication interface may be a transceiver, an interface circuit, a bus interface, a pin or other device capable of realizing transceiver functions.

[0068] In the seventh aspect, a computer-readable storage medium is provided, which stores instructions. When the computer-readable storage medium is run on a computer, the computer can execute the method for formulating a background data transmission strategy described in the first aspect or any possible design of the above aspects; or, execute the method for formulating a background data transmission strategy described in the second aspect or any possible design of the second aspect; or, execute the session management method described in the third aspect or any possible design of the third aspect; or, execute the UE policy management method described in the fourth aspect or any possible design of the fourth aspect.

[0069] In the eighth aspect, a computer program product comprising instructions is provided. The computer program product may include program instructions. When the computer program product is run on a computer, the computer can execute the method for formulating a background data transmission strategy described in the first aspect or any possible design of the above aspects; or, execute the method for formulating a background data transmission strategy described in the second aspect or any possible design of the second aspect; or, execute the session management method described in the third aspect or any possible design of the third aspect; or, execute the UE policy management method described in the fourth aspect or any possible design of the fourth aspect.

[0070] In a ninth aspect, a chip system is provided, comprising a processor and a communication interface. The chip system can be used to implement the functions performed by the first policy control network element in the first aspect or any possible design of the first aspect. For example, the processor is used to send a first message to the first network element via the communication interface to request a background data transmission policy stored by the first network element, obtain from the first network element the background data transmission policy stored by the first network element and second decision information for formulating a second background data transmission policy, and formulate the first background data transmission policy based on the first decision information for formulating the first background data transmission policy, the second decision information, and the background data transmission policy stored by the first network element.

[0071] In another possible design, the chip system can implement the function performed by the first network element in the above-mentioned second aspect or each possible design of the second aspect, or implement the function performed by the second policy control network element in the above-mentioned third aspect or each possible design of the third aspect, or implement the function performed by the second policy control network element in the above-mentioned fourth aspect or each possible design of the fourth aspect.

[0072] In one possible design, the chip system further includes a memory for storing program instructions and / or data. When the chip system is running, the processor executes the program instructions stored in the memory, causing the chip system to perform the method for formulating a background data transmission strategy described in the first aspect or any possible design of the first aspect. The chip system may be composed of a chip or may include a chip and other discrete components, without limitation.

[0073] In the tenth aspect, an embodiment of the present application further provides a communication system, which includes the communication device as described in the fifth aspect or the sixth aspect and a first network element. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 A flow chart of a method for formulating background data transmission strategies for an existing application;

[0075] Figure 2 A schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0076] Figure 2a A schematic diagram of the architecture of another communication system provided in an embodiment of the present application;

[0077] Figure 3a A schematic diagram of the architecture of a 5G communication system provided in an embodiment of the present application;

[0078] Figure 3b A schematic diagram of the architecture of a 4G communication system provided in an embodiment of the present application;

[0079] Figure 4 A schematic diagram of the composition of a communication device 400 provided in an embodiment of the present application;

[0080] Figure 5 A flowchart of a method for formulating a background data transmission strategy provided in an embodiment of the present application;

[0081] Figure 6 A flowchart of a method for formulating a background data transmission strategy provided in an embodiment of the present application;

[0082] Figure 7 A flowchart of a method for formulating a background data transmission strategy provided in an embodiment of the present application;

[0083] Figure 8 A schematic diagram of the composition of a communication device 80 provided in an embodiment of the present application;

[0084] Figure 9 A schematic diagram of the architecture of another communication system provided in an embodiment of the present application;

[0085] Figure 10A flowchart of a session management method provided in an embodiment of the present application;

[0086] Figure 11 A flowchart of a session management method provided in an embodiment of the present application;

[0087] Figure 12 A schematic diagram of the composition of a communication device 120 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0088] Before introducing the embodiments of the present application, the technical terms involved in the embodiments of the present application are described:

[0089] Background data: This type of data is transmitted non-real-time and typically runs in the background of a mobile device. For example, a user may need to upload or download large amounts of data to their mobile device, such as a smartphone or tablet computer. For example, uploading a batch of photos to a blog or downloading a video from a friend's blog takes time and uses system resources to process. Therefore, these uploaded or downloaded photos or videos are typically processed in the background of the mobile device. These uploaded or downloaded photos or videos can be referred to as background data.

[0090] Background data transfer (BDT) is a transmission method proposed by 3GPP to address the communication issues between a single application and a large number of terminal devices in the Internet of Things. By setting up off-peak hours, BDT provides lower-cost, faster communication between applications and terminal devices, while also alleviating network transmission pressure during peak hours. BDT is the core mode of AESE data transmission and is currently a hot topic in 3GPP research. Background data transmission refers to data transmission requests from various nodes in the 3GPP system (such as terminals, servers, and application servers) to the AESE. The AESE controls each data transmission request, determining when and at what rate to respond to each data transmission request to ensure load balancing.

[0091] Background data transmission policy is a policy that can be used to transmit background data. The background data transmission policy is formulated by the policy control network element. The background data transmission policy corresponds to the background data, and the background data transmission policy is uniquely identified by the policy identifier / reference identifier. The background data transmission policy may include one or more of the following: time window, rate within the time window, maximum aggregate bit rate, billing group identifier, reference identifier (reference ID) corresponding to the background data transmission policy. The background data transmission policy provides a transmission basis for background data and ensures the transmission requirements of background data. The background data transmission policy is bound to the decision information. The policy control network element can formulate the background data transmission policy based on the decision information and other information, such as all existing background data transmission policies, other network information (terminal access type, etc.), operator policies, etc.

[0092] The decision information may include one or more information such as the number of terminals, time window, network area information, traffic volume when each terminal transmits background data, or the reason for formulating the background data transmission strategy. The number of terminals may refer to the expected number of terminals that use the background data transmission strategy to transmit background data. The time window may refer to the time period for transmitting background data specified by the terminal user or preset by the system. The traffic volume when the terminal transmits background data may refer to the maximum transmission rate required when the terminal transmits background data. The network area information may be used to indicate the scope within which the background data transmission strategy can be applied. The network area information may be physical area information or a geographical location, such as a geographical location in a 3GPP network. If the decision information does not carry network area information, it indicates that the scope within which the background data transmission strategy corresponding to the decision information can be applied is the entire public land mobile network (PLMN).

[0093] The network information may refer to the current network status, and may be used to indicate which access network the terminal accesses, the type of wireless access technology used, the maximum transmission rate of the current network, and the like.

[0094] Among them, the operator policy can refer to the policy pre-made by the operator for the user (such as the user who uses the background data transmission policy to transmit background data). The operator policy may include one or more of the following: the user's usage level, the user's QoS requirements, the user's authorized bandwidth, etc.

[0095] Figure 1 This is a schematic diagram of formulating a background data transmission strategy in 3GPP. Since the policy control network element needs to negotiate with the application server during the formulation of the background data transmission strategy, in the embodiment of the present application, formulating the background data transmission strategy is to negotiate the background data transmission strategy, and the same applies below. Figure 1As shown, the method may include: S101: An application server sends a background data transfer request to a network open network element. The background data transfer request may carry an identifier (ID) of the application server and decision information for formulating a background data transfer policy. The background data transfer request is used to request the formulation of a background data transfer policy. Accordingly, the network open network element receives the background data transfer request. S102: The network open network element verifies and authorizes the background data transfer request, and after successful verification and authorization, sends the background data transfer request to a policy control network element. Accordingly, the policy control network element receives the background data transfer request. S103: The policy control network element sends a retrieval request to a network storage network element based on the background data transfer request. The retrieval request may be used to request all existing background data transfer policies. Accordingly, the network storage network element receives the retrieval request. S104: The network storage network element returns all existing / saved background data transfer policies to the policy control network element. Accordingly, the policy control network element receives all background data transfer policies saved by the network storage network element. S105: The policy control network element formulates one or more candidate background data transmission policies based on the decision information provided by the application server, all existing background data transmission policies, other network information (such as the terminal's access type), and operator policies. S106: The policy control network element returns a background data transfer response to the open network element. The background data transfer response carries the reference identifier (reference ID) assigned by the policy control network element to the background data transmission policy and one or more candidate background data transmission policies. S107: The open network element receives and returns the background data transfer response to the application server. S108: The application server receives the confirmation message, selects a background data transmission policy from one or more candidate background data transmission policies, and resends a background data transmission request to the open network element. The background data transmission request carries the reference identifier and the policy identifier of the selected background data transmission policy. S109: The open network element receives the background data transmission request and sends it to the policy control network element. S110: The policy control network element returns the background data transfer response to the open network element. S111: The open network element returns the background data transfer response to the application server. S112: The policy control network element sends a save request to the network storage network element to save the new background data transmission policy. The save request carries a reference identifier and the selected background data transmission policy. S113: The network storage network element receives and saves the new background data transmission policy and the reference identifier of the new background data transmission policy accordingly, and returns a confirmation message to the policy control network element.

[0096] It should be noted that Figure 1 The execution order of S110 to S113 is not restricted, and S110 and S111 can be as follows: Figure 1 As shown, it is executed before S112, or S112 and S113 may be executed first, and then S110 and S111, without limitation.

[0097] Further, the application server or terminal can transmit background data according to the background data transmission strategy. Subsequently, when transmitting background data according to the background data transmission strategy, if the network performance index is relatively low or the background data transmission strategy needs to be adjusted according to the user's application requirements, the background data transmission strategy can be referred to. Figure 1 In the process shown in S103 to S113 , a new background data transmission strategy is renegotiated / formulated.

[0098] Figure 1 In the process shown, the policy control network element needs to comprehensively consider all existing background data transmission policies to determine a new background data transmission policy. Since there may be multiple policy control network elements in the network, it is possible that multiple policy control network elements will simultaneously formulate background data transmission policies for multiple application servers. In this case, when formulating the background data transmission policy, each policy control network element does not consider the transmission policies being formulated by other policy control network elements. Therefore, the formulated transmission policies may not be optimal, resulting in conflicts in the formulated background data transmission policies. In addition, when the network-side device executes the policy according to the background data transmission policy, it does not consider whether the background data transmission policy has been updated, such as being modified by other network-side devices, resulting in a failure in executing the background data transmission policy.

[0099] To solve the above technical problems, an embodiment of the present application provides a method for formulating a background data transmission strategy: when a policy control network element decides to formulate / adjust a background data transmission strategy, the policy control network element carries decision information for formulating / adjusting the background data transmission strategy when requesting all existing output strategies from a network storage network element, and the network storage network element stores the decision information for formulating / adjusting the background data transmission strategy. Subsequently, when other policy control network elements send an acquisition request to the network storage network element to obtain an existing background data transmission strategy, the network storage network element provides the other policy control network elements with all existing background data transmission strategies and the stored decision information for formulating / adjusting the background data transmission strategy, so that the other policy control network elements formulate the background data transmission strategy based on all existing background data transmission strategies and the stored decision information being used to formulate / adjust the background data transmission strategy, or postpone the formulation until the background data transmission strategy to be formulated / adjusted is finally formulated and then formulate their own strategy.

[0100] It should be noted that the background data and background data transmission strategy described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Ordinary technicians in this field can know that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to conflict issues when formulating transmission strategies corresponding to other types of data.

[0101] The following describes the method for formulating a background data transmission strategy provided by an embodiment of the present application in conjunction with the accompanying drawings.

[0102] The method for formulating a background data transmission strategy provided in the embodiment of the present application can be used to Figure 2 The network shown, such as Figure 2 As shown, a communication system 10 provided in an embodiment of the present application is provided. The communication system 10 includes a first policy control network element and a first network element.

[0103] The first policy control network element can be used to formulate policies and charging control rules (PCC) such as background data transmission policy, service quality (quality of service) policy, slice selection policy, etc., and provide the formulated policies to network elements such as mobility management network element and session management network element.

[0104] The first network element may be called a network storage network element, and is used to store user data, such as user contract information, authentication or authorization data, etc. Specifically, the network storage network element may be a UDM network element, an NRF network element, or a UDR network element.

[0105] Specifically, the first policy control network element is configured to send a first message to the first network element, the first message being used to request the background data transmission policy stored by the first network element. The first network element is configured to receive the first message and return all stored background data transmission policies to the first policy control network element.

[0106] The first policy control network element is also used to obtain the background data transmission policy saved by the first network element and the second decision information for formulating the second background data transmission policy from the first network element, and formulate the first background data transmission policy based on the first decision information used to formulate the first background data transmission policy, the second decision information and the background data transmission policy saved by the first network element.

[0107] In one possible implementation, the first policy control network element is configured to, when determining that the second decision information affects the formulation of the first background data transmission policy, formulate the first background data transmission policy based on the first decision information, the second decision information, and the background data transmission policy stored by the first network element, with the execution of the first background data transmission policy and the second background data transmission policy not affecting each other. Alternatively, when determining that the second decision information affects the formulation of the first background data transmission policy, the first policy control network element, after obtaining the second background data transmission policy, formulates the first background data transmission policy based on the first decision information, the background data transmission policy stored by the first network element, and the second background data transmission policy.

[0108] Among them, in an embodiment of the present application, the second decision information affecting the formulation of the first background data transmission strategy may include one or more of the following situations: the first time window overlaps with the second time window, and the network area indicated by the first network area information overlaps with the network area indicated by the second network area information.

[0109] The first time window and the second time window may refer to time periods for transmitting background data, specified by the terminal user or preset by the system. The overlap between the first time window and the second time window may refer to partial or complete overlap. For example, the first time window may be from 6:00 AM to 9:00 AM, and the second time window may be from 6:00 AM to 9:00 AM or from 5:30 AM to 8:30 AM.

[0110] The first network area information can be used to indicate the applicable scope of the first background data transmission policy, and the second network area information can be used to indicate the applicable scope of the second background data transmission policy. The overlap between the network area indicated by the first network area information and the network area indicated by the second network area information can mean that the network area indicated by the first network area information partially overlaps or completely overlaps with the network area indicated by the second network area information. For example, the first network area can be cell 1, and the second network area can be cell 1 or a portion of cell 1.

[0111] Further, such as Figure 2 As shown, the communication system may further include a second policy control network element and a first application server. It should be noted that the second policy control network element may be the same as or different from the first policy control network element. When the second policy control network element is the same as the first policy control network element, Figure 2 There may be one policy control network element in the communication system shown.

[0112] The first application server can be deployed in a carrier network or a network deployed by a third-party provider that provides data transmission services to users, such as a carrier network that provides Internet Protocol (IP) Multimedia Services (IMS) to users. The first application server can be an application service (AS) or an application function (AF) and can provide background data transmission services to users.

[0113] Specifically, the first application server is configured to send a second message to the first policy control network element, where the second message includes the first decision information. The first policy control network element may be configured to receive the second message and send the first decision information to the first network element based on the second message. The first network element is further configured to receive and store the first decision information.

[0114] Among them, the function of the second policy control network element is similar to that of the first policy control network element. The second policy control network element is a network element that formulates a second background data transmission strategy based on the second decision information, such as: the second policy control network element is used to obtain the background data transmission strategy saved by the first network element from the first network element, and formulate the second background data transmission strategy based on the second decision information used to formulate the second background data transmission strategy and the background data transmission strategy saved by the first network element.

[0115] Furthermore, the second policy control network element is further configured to send second decision information to the first network element. The first network element is further configured to receive and store the second decision information.

[0116] It should be noted that, in this application, the first policy control network element and the second policy control network element can obtain the first decision information and the second decision information from the same application server, such as the first policy control network element and the second policy control network element can obtain the first decision information and the second decision information from the same application server. Figure 2 The first application server shown obtains the first decision information and the second decision information; alternatively, the first policy control network element and the second policy control network element may obtain the first decision information and the second decision information from different application servers.

[0117] When the first policy control network element and the second policy control network element obtain the first decision information and the second decision information from different sources, such as Figure 2a As shown, Figure 2 The illustrated communication system may further include a second application server.

[0118] The second application server is configured to send second decision information to the second policy control network element.

[0119] The second policy control network element is configured to obtain second decision information from the second application server.

[0120] further, Figure 2 or Figure 2a The communication system shown may also include a network open network element.

[0121] Network open network elements can be used to open core network events and capabilities, translate core network external parameters and internal parameters, receive and store identification information provided by core network external network elements, and perform core network element selection. Among them, core network external network elements can include application servers, etc.

[0122] For example, the first application server sending the second message to the first policy control network element may include:

[0123] The first application server is configured to send a second message to the network open function. The network open network element is configured to receive the second message, authenticate and authorize the second message, and then send the second message to the first policy control network element. The first policy control network element receives the second message from the network open network element.

[0124] It should be noted that Figure 2 or Figure 2a This is just an example architecture diagram. Figure 2 or Figure 2a In addition to the functional units shown in , the system may also include other functional network elements, such as: operation and management (O&M) network elements, etc., which are not limited in the embodiments of the present application. Figure 2 or Figure 2a The names of the devices in the Figure 2 or Figure 2a In addition to the names shown, each device can also be named other names, such as replacing them with network element names with the same or similar functions, without restriction.

[0125] in, Figure 2 The communication system shown can be a third generation partnership project (3GPP) communication system, such as a fourth generation (4G) communication system, a long term evolution (LTE) system, a fifth generation (5G) communication system or a new radio (NR) system, a next generation communication system, etc., or a non-3GPP communication system without limitation.

[0126] by Figure 2 The communication system shown is Figure 3aAs an example, the 5G communication system shown in FIG. Figure 3a As shown, the policy control network element can be a policy control function (PCF) in the 5G communication system, the network element or entity corresponding to the network exposure function network element can be a network exposure function (NEF) in the 5G communication system, and the network element or entity corresponding to the first network element can be an NRF network element or a UDR network element or a UDM network element in the 5G communication system.

[0127] by Figure 2 The communication system shown is Figure 3b As an example, the 4G communication system shown in FIG. Figure 3b As shown, the policy control network element may be a policy and charging rules function (PCRF) in a 4G communication system, the network element or entity corresponding to the network open function network element may be a service capability exposure function (SCEF) in a 4G communication system, and the network element or entity corresponding to the first network element may be a subscription profile repository (SPR) in a 4G communication system. Figure 3b As shown, the 4G communication system may further include a policy and charging enforcement function (PCEF).

[0128] Optionally, the policy control network element in the embodiment of the present application may also be referred to as a communication device, which may be a general device or a dedicated device, and the embodiment of the present application does not specifically limit this.

[0129] Optionally, the relevant functions of the policy control network element in the embodiment of the present application can be implemented by a single device, or by multiple devices, or by one or more functional modules within a single device, and the embodiment of the present application does not specifically limit this. It is understood that the above functions can be network elements in hardware devices, software functions running on dedicated hardware, or a combination of hardware and software, or virtualized functions instantiated on a platform (e.g., a cloud platform).

[0130] In the specific implementation, Figure 2 Each device shown (such as policy control network element, etc.) can use Figure 4 The structure shown, or including Figure 4 Parts shown. Figure 4This is a schematic diagram of the composition of a communication device 400 provided in an embodiment of the present application. The communication device 400 may include a processor 401 and a memory 404. Furthermore, the communication device 400 may also include a communication line 402 and a communication interface 403. The processor 401, the memory 404, and the communication interface 403 may be connected via the communication line 402.

[0131] Processor 401 may be a central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. Processor 401 may also be other devices with processing capabilities, such as circuits, devices, or software modules, without limitation.

[0132] The communication line 402 is used to transmit information between the components included in the communication device 400.

[0133] Communication interface 403 is used to communicate with other devices or other communication networks. Such other communication networks may be Ethernet, radio access networks (RAN), wireless local area networks (WLAN), etc. Communication interface 403 may be a module, circuit, transceiver, or any other device capable of communication.

[0134] The memory 404 is used to store instructions, where the instructions may be computer programs.

[0135] The memory 404 may be a read-only memory (ROM) or other type of static storage device that can store static information and / or instructions, or a random access memory (RAM) or other type of dynamic storage device that can store information and / or instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compact disc, laser disc, optical disc, digital versatile disc, Blu-ray disc), magnetic disk storage media, or other magnetic storage devices, without limitation.

[0136] It should be noted that the memory 404 can exist independently of the processor 401 or can be integrated with the processor 401. The memory 404 can be used to store instructions, program codes, or some data. The memory 404 can be located inside the communication device 400 or outside the communication device 400, without limitation.

[0137] Processor 401 is configured to execute instructions stored in memory 404 to implement the method for formulating a background data transmission policy provided in the following embodiments of this application. For example, when communication device 400 is a session management network element or a chip or system-on-chip in a session management network element, processor 401 executes instructions stored in memory 404 to implement the steps performed by the session management network element in the following embodiments of this application. For another example, when communication device 400 is a mobility management network element or a chip or system-on-chip in a mobility management network element, processor 401 may execute instructions stored in memory 404 to implement the steps performed by the mobility management network element in the following embodiments of this application.

[0138] In one example, the processor 401 may include one or more CPUs, such as Figure 4 CPU0 and CPU1 in.

[0139] As an optional implementation, the communication device 400 includes multiple processors, for example, Figure 4 In addition to the processor 401, a processor 407 may also be included.

[0140] As an optional implementation, the communication apparatus 400 further includes an output device 405 and an input device 406. For example, the input device 406 is a keyboard, a mouse, a microphone, a joystick, or the like, and the output device 405 is a display screen, a speaker, or the like.

[0141] It should be noted that the communication device 400 can be a desktop computer, a portable computer, a network server, a mobile phone, a tablet computer, a wireless terminal, an embedded device, a chip system or a computer with a plurality of CPUs. Figure 4 In addition, Figure 4 The structure shown in the figure does not constitute a limitation on the communication device, except Figure 4 In addition to the components shown, the communication device may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0142] In the embodiment of the present application, the chip system can be composed of chips, or can include chips and other discrete devices.

[0143] In addition, the actions and terms involved in the various embodiments of this application can refer to each other without limitation. The message names or parameter names in the messages exchanged between the various devices in the embodiments of this application are only examples, and other names can also be used in specific implementations without limitation.

[0144] The following combination Figure 2 The communication system shown in the figure describes the method for formulating background data transmission strategy provided by the embodiment of the present application. Each network element in the following embodiment may have Figure 4 The components shown are not described in detail here. It should be noted that the message names or parameter names in the messages exchanged between the various devices in the embodiment of the present application are only examples, and other names can also be used in specific implementations. For example, the formulation described in the embodiment of the present application can be replaced by terms such as decision-making and negotiation. The determination in the embodiment of the present application can also be understood as creation (create) or generation (generate), and the "include" in the embodiment of the present application can also be understood as "carrying", and the "formulation" in the embodiment of the present application can also be understood as "decision-making" or "determination", etc., which are uniformly explained here, and the embodiment of the present application does not make specific limitations on this.

[0145] Figure 5 A flow chart of a method for formulating a background data transmission strategy provided in an embodiment of the present application is shown as follows: Figure 5 As shown, the method may include:

[0146] S501: A first policy control network element sends a first message to a first network element. Correspondingly, the first network element receives the first message.

[0147] Among them, the first policy control network element can be Figure 2 Any policy control network element in the communication system shown.

[0148] Among them, the first network element can be a UDR network element or a UDM network element or an NRF network element or other network elements that can save background data transmission policies. The first network element can save the background data transmission policies and the reference identifiers of the background data transmission policies in a list or in the first network element in the form of an array. Taking the background data transmission policies and the reference identifiers of the background data transmission policies as an example, in the initial state, the list is empty. After the first network element receives the background data transmission policies and the reference identifiers of the background data transmission policies sent by the policy control network element, the background data transmission policies and the reference identifiers of the background data transmission policies are saved in the list. The relevant description of the background data transmission policies can be referred to above and will not be repeated here.

[0149] Furthermore, the first network element may also store decision information corresponding to the background data transmission strategy being formulated, and the decision information may be stored in the first network element in correspondence with the reference identifier corresponding to the background data transmission strategy being formulated. Exemplarily, the correspondence between the decision information corresponding to the background data transmission strategy being formulated and the reference identifier may be included in the same list as the correspondence between the formulated background data transmission strategy and the reference identifier of the background data transmission strategy. For example, Table 1 below shows the decision information corresponding to the background data transmission strategy already stored in the first network element and the background data transmission strategy being formulated. As shown in Table 1, the first network element stores background data transmission strategy 1 and background data transmission strategy 2, and also stores decision information 3 corresponding to the background data transmission strategy with reference identifier reference ID3. The background data transmission strategy with reference identifier reference ID3 has not been completed or is being formulated, that is, the background data transmission strategy with reference identifier reference ID3 is under negotiation. If background data transmission strategy 3 corresponding to reference ID3 already existed, decision information 1 also indicates that background data transmission strategy 3 is not a valid background data transmission strategy.

[0150] Table 1

[0151] Reference Designator Background data transmission strategy reference ID1 Background Data Transmission Strategy 1 reference ID2 Background Data Transmission Strategy 2 reference ID3 Decision Information 1

[0152] The first message may be used to request all background data transmission policies saved by the first network element, or may be replaced by the first message being used to request all existing / existing / established background data transmission policies. The first message may be a data management (DM) service_query request (DM_query request) provided by the interface between the first network element and the first policy control network element. The first message may include a first reference identifier and first decision information. The first reference identifier may be used to identify the first background data transmission policy, and the first reference identifier information is allocated by the first policy control network element. The first decision information may be information provided by the first application server to the first policy control network element that can be used to formulate / decide / adjust the first background data transmission policy. The first decision information may include one or more information such as the number of first terminals, the first time window, the first network area information, the first traffic volume when each terminal transmits background data, an indication that the first background data transmission policy is being negotiated, or the reason for formulating the first background data transmission policy.

[0153] It should be noted that if the first background data transmission policy is initially formulated / established for the first time, the reason for establishing the first background data transmission policy may not be carried. However, if the first background data transmission policy is adjusted, the reason for establishing the first background data transmission policy may be carried. The reason for establishing the first background data transmission policy may be network performance degradation, network performance recovery, or a change in the operator's policy.

[0154] The present application is not limited to including the first reference identifier and the first decision information in the first message and sending it to the first network element. The first policy control network element may also send the first reference identifier and the first decision information to the first network element through other messages, so that the first network element saves the first reference identifier information and the first decision information. For example, the first policy control network element may send a third message to the first network element, and the third message includes the first reference identifier and the first decision information. The following methods may be used to indicate that the first background data transmission policy is being formulated (i.e., being negotiated): the first policy control network element may carry the first decision information through a special information element to indicate that the background data transmission policy corresponding to the first reference identifier is being formulated (i.e., being negotiated) (i.e., indicating that it is not a valid background data transmission policy, the same below), or include a special identifier in the first decision information to indicate that the background data transmission policy corresponding to the first reference identifier is being formulated (i.e., being negotiated), or use the reason for formulating the first background data transmission policy to indicate that the background data transmission policy corresponding to the first reference identifier is being formulated (i.e., being negotiated).

[0155] The first number of terminals may refer to the number of terminals expected to transmit background data using the first background data transmission policy. The first traffic flow rate when a terminal transmits background data may refer to the maximum transmission rate required by the terminal when transmitting background data. The description of the first time window and the first network area information is as described above and is not repeated here.

[0156] In one example, after the first policy control network element receives the second message sent by the first application server, the first policy control network element is triggered to send the first message to the first network element.

[0157] The second message may be used to request the formulation of the first background data transmission strategy. The second message may include the first decision information, and may also include the identifier of the first application server and other information, etc., without limitation.

[0158] The identifier of the first application server may be used to identify the first application server, and the identifier of the first application server may be an Internet protocol (IP) address or a first media access control (MAC) address of the first application server.

[0159] Specifically, when a user needs to transmit background data, the user can trigger the application layer of the terminal to send a transmission request to the first application server. The transmission request can carry the time period, transmission rate, etc. that the user desires to transmit the background data. After receiving the transmission request, the first application server determines the first decision information based on the transmission request and sends a second message to the first policy control network element. For example, assuming that the current time is 2:00 p.m. and the user wants to download a 200MB movie during working hours (before 6:00 p.m.), the user can trigger the application layer of the terminal to send this request to the application server. The application server generates decision information based on the request and sends a second message carrying the decision information to the first policy control network element, triggering the first policy control network element to formulate a corresponding background data transmission policy so that the user can enjoy the movie at home after getting home from get off work.

[0160] When the first application server is an application server deployed by a third party, the first application server can send the second message to the first policy control network element through the network open network element. For example, the first application server sends the second message to the network open network element, and the network open network element authenticates and authorizes the second message before sending the second message to the first policy control network element. Alternatively, when the first application server is an application server deployed by an operator, the first application server can send the second message directly to the first policy control network element.

[0161] In another example, before executing S501, the first policy control network element has already formulated a background data transmission policy, such as a third background data transmission policy, based on the first decision information. When the first policy control network element determines that a network performance indicator during a time window of the third background data transmission policy is lower than a preset threshold, the first policy control network element is triggered to send a first message to the first network element. Alternatively, before executing S501, the first policy control network element has already formulated a background data transmission policy, such as the third background data transmission policy, based on the first decision information. The network performance indicator when transmitting background data according to the third background data transmission policy is poor, such as lower than a preset threshold. In this case, when the first policy control network element determines that the network performance indicator during the time window of the third background data transmission policy has returned to the preset threshold, the first policy control network element is triggered to send the first message to the first network element. In this case, the formulation of the first background data transmission policy by the first policy control network element can be replaced by the description that the first policy control network element adjusts the third background data transmission policy to obtain the first background data transmission policy. The third background data transmission policy can be referred to as the background data transmission policy before adjustment, and the first background data transmission policy can be referred to as the background data transmission policy after adjustment. At this time, a special information element is used to carry the first decision information, or the first decision information includes an indication that a background data transmission policy is being formulated, or a reason for formulating the background data transmission policy. The first decision information is also used to indicate that the third background data transmission policy is not a valid background data transmission policy.

[0162] The preset threshold value may be set as required, and may be set by an operator. For example, the operator may set the preset threshold value based on the user's level, the user's QoS requirement, authorized bandwidth, and the like.

[0163] Among them, the first policy control network element can determine whether the network performance indicator is lower than or restored to the preset threshold by itself, or learn from other network elements whether the network performance indicator is lower than or restored to the preset threshold, such as the first policy control network element sends a subscription request to the network data analytics function (NWDAF), and the subscription request is used to obtain network performance indicator events. The network performance indicator event is an event in which the network performance indicator is lower than or restored to the preset threshold during the third background data transmission policy time window; the first policy control network element receives a network performance indicator event notified by the NWDAF. Network performance indicators may include transmission rate, transmission bandwidth, etc.

[0164] In the method for a first policy control network element to send a third message to a first network element, the third message including a first reference identifier and first decision information, the first policy control network element first sends a first message to the first network element, requesting the background data transmission policy stored by the first network element. The first network element sends the stored background data transmission policy and corresponding decision information to the first policy control network element, including a third background data transmission policy and first decision information used to determine the third background data transmission policy (which is also used to determine the first background data transmission policy) (the first decision information does not include an indication that the background data transmission policy is currently being negotiated or a reason for establishing the background data transmission policy). When the first policy control network element determines that the first background data transmission policy needs to be re-established, the first policy control network element sends the updated first decision information to the first network element via a third message. The first policy control network element may carry the first decision information via a special information element to indicate that the background data transmission policy corresponding to the first reference identifier is currently being established (i.e., being negotiated) (i.e., indicating that the background data transmission policy corresponding to the first reference identifier is currently being established (i.e., being negotiated), or include a special identifier in the first decision information to indicate that the background data transmission policy corresponding to the first reference identifier is currently being established (i.e., being negotiated), or use a reason for establishing the first background data transmission policy to indicate that the background data transmission policy corresponding to the first reference identifier is currently being established (i.e., being negotiated).

[0165] S502: The first network element sends all background data transmission policies and second decision information stored in the first network element to the first policy control network element according to the first message. Correspondingly, the first policy control network element obtains all background data transmission policies and second decision information stored in the first network element from the first network element.

[0166] Among them, the second decision information can be decision information saved by the first network element and used to formulate a second background data transmission strategy. The second background data transmission strategy corresponding to the second decision information has not been completed or is being formulated (i.e., it is being negotiated). The second decision information can be provided by the second application server to the second policy control network element. When the second policy control network element requests all existing background data transmission strategies from the first network element, the second decision information and the second reference identifier assigned by the second policy control network element to the second background data transmission strategy are sent to the first network element. The first network element receives and correspondingly saves the second decision information and the second reference identifier, or the second policy control network element sends the second reference identifier and the second decision information to the first network element through other messages. The second policy control network element and the first policy control network element can be the same or different, and the second application server and the first application server can be the same or different, without limitation.

[0167] The second decision information may include one or more information such as the number of second terminals, a second time window, second network area information, a second traffic volume when each terminal transmits background data, an indication that the second background data transmission strategy is being negotiated, or a reason for formulating the second background data transmission strategy. The first network element may carry the second decision information through a special information element to indicate that the second background data transmission strategy is being formulated (i.e., being negotiated), or include a special identifier in the second decision information to indicate the second background data transmission strategy, or use the reason for formulating the second background data transmission strategy in the second decision information to indicate that the second background data transmission strategy is being formulated (i.e., being negotiated).

[0168] Taking the second decision information as decision information 1 in Table 1 as an example, after receiving the first message, the first network element can query Table 1 and send background data transmission policy 1, background data transmission policy 2 and decision information 1 to the first policy control network element.

[0169] Exemplarily, the first network element may send a data management service_query response (DM_query response) provided by the interface between the first network element and the first policy control network element to the first policy control network element. The DM_query response may include all background data transmission policies and the second decision information saved by the first network element.

[0170] Furthermore, the first network element may store the correspondence between the first decision information and the first reference identifier, such as storing the correspondence between the first decision information and the first reference identifier in the above-mentioned Table 1.

[0171] S503: The first policy control network element formulates a first background data transmission policy according to the first decision information, all background data transmission policies stored by the first network element, and the second decision information.

[0172] For example, the first policy control network element may determine whether the second decision information affects the formulation of the first background data transmission strategy. If the second decision information does not affect the formulation of the first background data transmission strategy, the first policy control network element may refer to Figure 1 The first background data transmission policy is formulated in the manner shown; if the second decision information affects the formulation of the first background data transmission policy, the first policy control network element may adopt the following manner 1, manner 2, or manner 3 to formulate the first background data transmission policy. The relevant definition of how the second decision information affects the formulation of the first background data transmission policy can be referred to above and is not elaborated on here.

[0173] Method 1: The first policy control network element formulates a first background data transmission policy according to the first decision information, the second decision information and all background data transmission policies stored by the first network element. The execution of the first background data transmission policy and the second background data transmission policy do not affect each other.

[0174] Among them, the first policy control network element can refer to Figure 1 The method shown continues to formulate the first background data transmission strategy, that is, the first background data transmission strategy and the second background data transmission strategy are formulated simultaneously or in parallel. However, after the formulation is completed, when data transmission is performed according to the background data transmission strategy, it is required / guaranteed that the execution of the first background data transmission strategy and the second background data transmission strategy do not affect each other. For example, the execution of the first background data transmission strategy and the second background data transmission strategy is required to meet one or more of the following: the time window of the first background data transmission strategy and the time window of the first background data transmission strategy do not overlap, and the maximum transmission rate of the first background data transmission strategy and the second background data transmission strategy when they are simultaneously executed in the same network area will not exceed the preset threshold of the network performance indicator set by the operator.

[0175] Method 2: The first policy control network element delays the formulation of the first background data transmission strategy. For example, after the first policy control network element obtains the second background data transmission strategy, that is, after the second background data transmission strategy is formulated and there are no other background data transmission strategies being formulated in the network, the first policy control network element formulates the first background data transmission strategy based on the first decision information, all background data transmission strategies saved by the first network element, and the second background data transmission strategy.

[0176] Among them, in method 2, the first policy control network element obtains the second background data transmission strategy, which may include: the second policy control network element is different from the first policy control network element, and the first policy control network element obtains the second background data transmission strategy from the first network element, such as the second policy control network element can receive the second decision information from the second application server, and send the second decision information to the first network element. At the same time, the second policy control network element obtains all background data transmission strategies saved by the first network element from the first network element, formulates candidate background data transmission strategies based on all background data transmission strategies, the second decision information and other information saved by the first network element, and finally selects the second background data transmission strategy from the formulated candidate background data transmission strategies through interaction with the second application server, and sends it to the first network element, triggering the first network element to send it to the first policy control network element. Alternatively, in another possible design, the second policy control network element is the same as the first policy control network element. After receiving the second decision information from the second application server, the second policy control network element obtains all background data transmission policies saved by the first network element from the first network element, formulates candidate background data transmission policies based on all background data transmission policies saved by the first network element, the second decision information and other information, and finally selects the second background data transmission policy from the formulated candidate background data transmission policies through interaction with the second application server.

[0177] Method 3: The first policy control network element delays formulating the first background data transmission policy, such as when the second policy control network element fails to negotiate the second background data transmission policy with the second application server. The second policy control network element requests the first network element to delete the second decision information, and the first network element requests the first policy control network element to delete the second decision information. For example, the first network element may send a deletion instruction corresponding to the second decision information to the first policy control network element. After the first policy control network element obtains the deletion instruction corresponding to the second decision information, it formulates the first background data transmission policy based on the first decision information and all background data transmission policies stored by the first network element.

[0178] The deletion indication corresponding to the second decision information may be replaced by the deletion indication corresponding to the second reference identifier, and the deletion corresponding to the second decision information may be used to indicate deletion of the second decision information and / or the second background data transmission strategy corresponding to the saved second decision information.

[0179] It should be noted that, when the first policy control network element obtains the second background data transmission policy from the first network element or obtains the deletion indication corresponding to the second decision information, before executing S502, the method further includes: the first policy control network element subscribes to a first event from the first network element, and the first event is an event notification of a change in the background data transmission policy / decision information saved by the first network element, so that when the saved background data transmission policy changes, the first network element notifies the first policy control network element of the changed background data transmission policy, or notifies the first policy control network element of all background data transmission policies after the change in the first network element, or notifies the first policy control network element of the change in the decision information. Among them, the background data transmission policy change may include adding, deleting, or updating the background data transmission policy. The change in decision information may include deleting decision information, or updating the content included in the decision information, or adding new decision information, etc.

[0180] Among them, in the second method, the first policy control network element can refer to Figure 1 The first background data transmission strategy is formulated in the manner shown, such as the first policy control network element can formulate one or more candidate background data transmission strategies based on the first decision information, all background data transmission strategies (including the second background data transmission strategy) saved by the first network element, the current network status, the operator strategy, etc., and formulate candidate background data transmission strategies including the first background data transmission strategy, so that the first application server selects the first background data transmission strategy from the candidate background data transmission strategies.

[0181] Among them, in method three, the first policy control network element can refer to Figure 1 The first background data transmission strategy is formulated in the manner shown, such as the first policy control network element can formulate one or more candidate background data transmission strategies based on the first decision information, all background data transmission strategies stored by the first network element, the current network status, the operator strategy, etc., and formulate candidate background data transmission strategies including the first background data transmission strategy, so that the first application server selects the first background data transmission strategy from the candidate background data transmission strategies.

[0182] The first decision information may be acquired by the first network element in the first policy control network element, or may be stored locally in the first policy control network element.

[0183] Further, Figure 5 The method may further include:

[0184] S504: The first policy control network element sends a first background data transmission policy and a first reference identifier to the first network element.

[0185] Exemplarily, the first policy control network element may send a data management service_update request (DM_update request) provided by the interface between the first network element and the first policy control network element to the first network element, where the DM_update request carries the first background data transmission policy and the first reference identifier.

[0186] S505: The first network element receives the first background data transmission policy and the first reference identifier, stores the first background data transmission policy and the first reference identifier accordingly, and the first policy controls the network element to send a confirmation message.

[0187] The confirmation message may be a data management service_update response (DM_update response) provided by an interface between the first network element and the first policy control network element.

[0188] It should be noted that, if before S504, that is, before the first background data transmission policy is completed, there is a third application server requesting the third policy control network element to formulate a background data transmission policy based on the third decision information, and the third policy control network element requests the first network element for an existing background data transmission policy, then the first network element can send all existing background data transmission policies and the first decision information to the third policy control network element, so that the third policy control network element can formulate a background data transmission policy based on the third decision information, the existing background data transmission policy, and the first decision information, thereby avoiding conflicts when multiple background data transmission policies are formulated simultaneously. Among them, the first policy control network element, the second policy control network element, and the third policy control network element can be the same or different, without limitation.

[0189] based on Figure 5 In the method shown, when formulating background data transmission policies, the policy control network element not only refers to the existing background data transmission policies, but also refers to the decision information required by other policy control network elements to formulate background data transmission policies, so as to avoid conflicts between the formulated background data transmission policies and other background data transmission policies and ensure the availability of the background data transmission policies.

[0190] The following combination Figure 3a In the 5G communication system shown, the policy control network element is PCF (such as the first policy control network element is PCF2, and the second policy control network element is PCF1), the application server is AF (such as the first application server is AF2, and the second application server is AF1), the first network element is a UDR network element, the first background data transmission strategy is background data transmission strategy 2, the second background data transmission strategy is background data transmission strategy 1, the first decision information is decision information 2, and the second decision information is decision information 1. As an example, the method for formulating a background data transmission strategy provided in an embodiment of the present application is described.

[0191] Figure 6 A flow chart of a method for formulating a background data transmission strategy provided in an embodiment of the present application is shown as follows: Figure 6 As shown, the method may include:

[0192] S601: AF1 sends message 1 to NEF.

[0193] Among them, AF1 can be Figure 3a Any AF in the system shown provides background data.

[0194] Message 1 may be used to request the formulation of background data transmission policy 1. Message 1 may be a background data transmission policy negotiation service_establishment request (Nnef_BDTPNegotiantion_Create request) provided by the Nnef interface. Message 1 may carry an identifier of AF1 and decision information 1. Decision information 1 may be used to formulate background data transmission policy 1. Decision information 1 may include one or more pieces of information, such as the number of first terminals, a first time window, first network area information, a first traffic volume when each terminal transmits background data, or a reason for formulating background data transmission policy 1. It should be noted that if AF1 initially formulates background data transmission policy 1, the reason for formulating background data transmission policy 1 may not be carried.

[0195] S602: NEF receives message 1, verifies and authorizes message 1. NEF successfully authorizes message 1, and sends message 1 to PCF1.

[0196] For example, NEF can check whether AF1 identified by the ID has a contract with the network based on the ID of AF1 carried in message 1, such as whether there is a contract between the third-party provider and the operator. If so, the authorization is successful; otherwise, the authorization fails and the process ends.

[0197] Among them, PCF1 can be a PCF that can provide policy formulation services for AF1.

[0198] For example, the message 1 sent by AF1 to NEF and the message 1 sent by NEF to PCF1 may carry the same content, but the message types of the two may be different. For example, the message 1 sent by NEF to PCF1 may be the background data transmission policy control service_establishment request (Npcf_BDTPolicyControl_Create request) provided by the Npcf interface. The message 1 sent by NEF to PCF1 may include the above-mentioned decision information 1 and may also include the ID of AF1.

[0199] It should be noted that although the first network area information sent by AF1 to NEF and the first network area information sent by NEF to PCF1 identify the same area, the information formats of the two are different. The first network area information sent by AF1 to NEF can be network area information identifiable by a third party, such as a geographic location in a 3GPP network. The first network area information sent by NEF to PCF1 can be network area information identifiable by core network elements, such as a cell identifier.

[0200] S603: PCF1 receives message 1 and sends message 2 to the UDR network element.

[0201] Among them, message 2 can be the data management service _query request (Nudr_DM_queryrequest) provided by the Nudr interface. Message 2 is used to request all background data transmission policies saved by the UDR network element. Message 2 can carry the reference identifier assigned by PCF1 to background data transmission policy 1: reference Id1 and the above-mentioned received decision information 1. This application is not limited to carrying reference Id1 and decision information 1 in message 2 and sending it to the UDR. PCF1 can also send reference Id1 and decision information 1 to the UDR through other messages.

[0202] In addition to the content described in S601, decision information 1 may also include an indication that background data transmission policy 1 is being negotiated (i.e., being negotiated). For example, PCF 1 may carry decision information 1 in a special information element to indicate that the background data transmission policy corresponding to reference ID 1 is being negotiated, or include a special identifier in decision information 1 to indicate that the background data transmission policy corresponding to reference ID 1 is being negotiated, or use the reason for establishing background data transmission policy 1 in decision information 1 to indicate that the background data transmission policy corresponding to reference ID 1 is being negotiated.

[0203] S604: The UDR network element receives message 2 and returns all background data transmission policies saved by the UDR network element to PCF1.

[0204] Furthermore, the UDR network element correspondingly stores decision information 1 and reference Id1.

[0205] It should be noted that, if the UDR network element stores decision information required by other PCFs in formulating background data transmission strategies, the UDR network element also returns the decision information stored in the UDR network element.

[0206] S605: PCF1 receives all background data transmission policies saved by the UDR network element, and formulates one or more candidate background data transmission policies according to all background data transmission policies saved by the UDR network element, the current network status, operator policies, etc.

[0207] The candidate background data transmission strategies are some background data transmission strategies that may be selected by AF1 as background data transmission strategy 1. A candidate background data transmission strategy may include one or more information such as strategy identifier, recommended transmission time window, maximum aggregate bit rate, and charging group identifier.

[0208] Exemplarily, the process of PCF1 formulating one or more candidate background data transmission strategies according to all background data transmission strategies saved by the UDR network element and the current network status, operator strategy, etc. can refer to the existing technology and will not be described in detail.

[0209] Furthermore, after PCF1 formulates one or more candidate background data transmission strategies, it executes Figure 1 As shown in S106 to S113, during the process of PCF1 executing S106 to S113, other PCFs may also formulate background data transmission strategies, such as PCF2, which means that two or more PCFs may formulate background data transmission strategies at the same time. Specifically, the process is shown in the following steps:

[0210] S606: AF2 sends message 3 to NEF.

[0211] Message 3 may be Nnef_BDTPNegotiantion_Create request, and may include AF2's ID and decision information 2. AF2's ID may be used to identify AF2, and decision information 2 is as described above in decision information 1. Decision information 2 may be used to formulate background data transmission policy 2. Exemplarily, decision information 2 may include one or more pieces of information, such as the number of second terminals, a second time window, second network area information, a second traffic volume when each terminal transmits background data, or a reason for formulating background data transmission policy 2. It should be noted that if AF2 initially formulates background data transmission policy 2, the reason for formulating background data transmission policy 2 may not be carried.

[0212] S607: NEF receives message 3, verifies and authorizes message 3. NEF successfully authorizes message 3, and sends message 3 to PCF2.

[0213] Among them, S607 can refer to S602 and will not be described in detail.

[0214] S608: PCF2 receives message 3 and sends message 4 to the UDR network element.

[0215] Among them, message 4 can be Nudr_DM_query request, message 4 can be similar to the above-mentioned message 2, and message 4 can be used to request to obtain all existing / saved background data transmission policies of the UDR network element. Message 4 can include reference Id2 and decision information 2 assigned by PCF2 to background data transmission policy 2. This application is not limited to carrying reference Id1 and decision information 1 in message 4 and sending it to the UDR. PCF2 can also send reference Id2 and decision information 2 to the UDR through other messages.

[0216] In addition to the content described in S606, decision information 2 may also include an indication that background data transmission policy 2 is being negotiated. For example, PCF2 may carry decision information 2 in a special information element to indicate that the background data transmission policy corresponding to reference ID 2 is being negotiated, or include a special identifier in decision information 2 to indicate that the background data transmission policy corresponding to reference ID 2 is being negotiated, or use the reason for establishing background data transmission policy 2 in decision information 2 to indicate that the background data transmission policy corresponding to reference ID 2 is being negotiated.

[0217] S609: The UDR network element receives message 4 and returns all existing background data transmission policies and the decision information 1 received in S604 to PCF2.

[0218] Furthermore, the UDR network element stores reference Id2 and decision information 2 accordingly.

[0219] The UDR may carry decision information 1 through a special cell to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or include a special identifier in the decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or use the reason value for formulating background data transmission policy 1 in the decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated.

[0220] S610 : PCF2 determines that decision information 1 affects formulation of background data transmission strategy 2 .

[0221] The decision information 1 affecting the formulation of the background data transmission strategy 2 may include one or more of the following: the first time window overlaps with the second time window, and the network area indicated by the first network area information overlaps with the network area indicated by the second network area information.

[0222] Furthermore, PCF2 does not delay the decision, but refers to Figure 1 As shown in S105 to S113, one or more candidate background data transmission strategies are formulated and one or more candidate background data transmission strategies are indicated to AF2. After AF2 selects background data transmission strategy 2 from one or more candidate background data transmission strategies, background data transmission strategy 2 is saved in the UDR network element. Specifically, the process can be referred to Figure 1 At this time, PCF2 can formulate the background data transmission strategy in parallel with PCF1, and after executing S616, the process ends.

[0223] However, when PCF2 does not delay the decision, when executing background data transmission strategy 1 and background data transmission strategy 2 subsequently, it is necessary to ensure that the execution of background data transmission strategy 1 and background data transmission strategy 2 do not affect each other, such as ensuring one or more of the following: the time windows of background data transmission strategy 1 and background data transmission strategy 2 are set to non-overlapping, and the maximum transmission rate of background data transmission strategy 1 and background data transmission strategy 2 when they are executed simultaneously in the network intersection area (that is, the same network area) will not exceed the preset threshold of the network performance indicator set by the operator, etc.

[0224] Alternatively, PCF2 delays the decision and formulates the background data transmission strategy 2 after S618 , that is, PCF1 and PCF2 formulate the background data transmission strategy in sequence, and the process ends after PCF2 completes formulating the background data transmission strategy 2 .

[0225] S611: PCF1 formulates one or more candidate background data transmission strategies according to decision information 1, all existing background data transmission strategies, current network status and operator strategy, and sends confirmation message 1 to NEF.

[0226] The confirmation message 1 may be Npcf_BDTPNegotiantion_Create response, and the confirmation message 1 may carry reference Id1 and one or more candidate background data transmission strategies formulated by PCF1.

[0227] S612: NEF receives the confirmation message 1 and returns a notification message 1 to AF1.

[0228] The notification message 1 may carry a reference Id1 and one or more candidate background data transmission strategies.

[0229] S613: AF1 receives Notification Message 1. If AF1 decides to select one of the one or more candidate background data transmission policies as Background Data Transmission Policy 1, AF1 sends an Update Request 1 to the NEF, carrying Reference Id 1 and the policy identifier of the selected Background Data Transmission Policy 1. If AF1 rejects all candidate background data transmission policies, AF1 sends an Update Request 1 to the NEF, carrying a rejection indication. The Update Request 1 may be a Nnef_BDTPNegotiantion_Update request.

[0230] S614: NEF receives the update request 1 and sends the update request 1 to PCF1.

[0231] It should be noted that the update request 1 sent by AF1 to NEF and the update request 1 sent by NEF to PCF1 may carry the same content, but the message types may be different. The update request 1 sent by NEF to PCF1 may be Npcf_BDTPolicyControl_Update request.

[0232] S615: PCF1 receives update request 1 and sends update request 2 to the UDR network element.

[0233] The update request 2 may be a Nudr_DM_Update Request.

[0234] Exemplarily, PCF1 may send update request 2 to the UDR based on the content in update request 1. For example, if update request 1 carries reference Id1 and the policy identifier of the selected background data transmission policy 1, then update request 2 carries reference Id1 and the selected background data transmission policy 1; if update request 1 carries a rejection indication, then the update request may carry reference Id1 and a deletion indication, and the deletion indication may be used to instruct deletion of the decision information and / or background data transmission policy corresponding to reference Id1.

[0235] S616: The UDR network element receives the update request 2 and returns a response to the update request 2 to PCF1.

[0236] The response to the update request 2 may be Nudr_DM_Update_response.

[0237] Furthermore, when the update request 2 carries reference Id1 and a new background data transmission strategy 1, the UDR network element saves the reference Id1 and the new background data transmission strategy 1 accordingly; or, when the update request 2 carries reference Id1 and a deletion indication, the decision information 1 corresponding to the reference Id1 is deleted (i.e., the saved background data transmission strategy 1 is deleted).

[0238] S617: Based on the fact that PCF2 has previously subscribed to the background data transmission policy change event notification from the UDR network element, the UDR network element sends a new background data transmission policy 1 or an indication to delete the decision information 1 corresponding to reference Id1 (i.e., an indication to delete the background data transmission policy 1) to PCF2.

[0239] Exemplarily, the UDR network element may send a Nudr_DM_Notification Request to PCF2, where the Nudr_DM_Notification Request carries a new background data transmission policy 1 or an indication of deleting the decision information 1 corresponding to reference Id1 (ie, an indication of deleting the background data transmission policy 1).

[0240] S618: PCF2 receives the new background data transmission policy 1 or the instruction to delete the decision information 1 (ie, the instruction to delete the background data transmission policy 1), and returns a response message to the UDR network element.

[0241] S619: PCF2 formulates one or more candidate background data transmission strategies for AF2 based on decision information 2, all existing background data transmission strategies (including background data transmission strategy 1), the current network status and the operator strategy; or PCF2 formulates one or more candidate background data transmission strategies for AF2 based on decision information 2, all existing background data transmission strategies (excluding background data transmission strategy 1), the current network status and the operator strategy.

[0242] S620: PCF2 sends a confirmation message 2 to NEF.

[0243] The confirmation message 2 may be Npcf_BDTPNegotiantion_Create response, and the confirmation message 2 may carry reference Id2 and one or more candidate background data transmission strategies formulated by PCF2.

[0244] S621: NEF receives the confirmation message 2 and returns a notification message 2 to AF2.

[0245] The notification message 2 may carry reference ID2 and one or more candidate background data transmission strategies.

[0246] S622: AF2 receives notification message 2. If AF2 decides to select one of the background data transmission policies from one or more candidate background data transmission policies as background data transmission policy 2, AF2 carries reference Id2 and the policy identifier of the selected background data transmission policy 2 in the update request 3 sent to NEF; if AF2 rejects all candidate background data transmission policies, AF2 carries a rejection indication in the update request 3 sent to NEF.

[0247] The update request 3 may be Nnef_BDTPNegotiantion_Update request.

[0248] S623: NEF receives update request 3 and sends update request 3 to PCF2.

[0249] It should be noted that the update request 3 sent by AF2 to NEF and the update request 3 sent by NEF to PCF2 may carry the same content, but the message types may be different. The update request 3 sent by NEF to PCF2 may be Npcf_BDTPolicyControl_Update request.

[0250] S624: PCF2 receives update request 3 and sends update request 4 to the UDR network element.

[0251] The update request 4 may be a Nudr_DM_Update Request. If the update request 3 carries reference ID 2 and the selected background data transmission policy 2, then the update request 4 carries reference ID 2 and the selected background data transmission policy 2. If the update request 3 carries a rejection indication, then the update request 4 carries reference ID 2 and a deletion indication. The deletion indication may be used to instruct deletion of the decision information 2 and / or background data transmission policy 2 corresponding to the reference ID 2.

[0252] S625: The UDR network element receives the update request 4 and returns a response to the update request 4 to PCF2.

[0253] The response to the update request 4 may be Nudr_DM_Update_response.

[0254] Furthermore, when the update request 4 carries reference Id2 and a new background data transmission policy 2, the UDR network element correspondingly saves reference Id2 and background data transmission policy 2. When the update request 4 carries reference Id1 and a deletion indication, the UDR deletes the decision information 2 (i.e., deletes the saved background data transmission policy 2).

[0255] based on Figure 6 In the method shown, when formulating background data transmission strategies, multiple PCFs not only refer to existing background data transmission strategies, but also refer to the decision information required by other PCFs to formulate background data transmission strategies, thereby avoiding conflicts with the formulation of other PCFs and ensuring the availability of background data transmission strategies.

[0256] Figure 6 The method shown is described by taking the AF requesting to formulate a background data transmission strategy as an example. Alternatively, when the network performance index is lower than or restored to a preset threshold, the PCF can also be triggered to execute the process described in the embodiment of the present application. The process is as follows Figure 7 shown. Figure 7 A flow chart of a method for formulating a background data transmission strategy provided in an embodiment of the present application is shown as follows: Figure 7 As shown, the method may include:

[0257] S701: PCF1 determines that a network performance indicator is lower than or restored to a preset threshold.

[0258] The preset threshold can be set as needed and is not restricted. For example, after a transmission window is allocated, if the network changes and the network load becomes relatively congested during that period, the rate will also become higher, resulting in high user transmission rates and failing to meet the user's need for network transmission at the lowest cost. In other words, the network performance indicator falls below the preset threshold.

[0259] Exemplarily, PCF1 can determine by itself whether the network performance indicator is lower than or restored to the preset threshold; or, PCF1 can learn from other network elements whether the network performance indicator is lower than or restored to the preset threshold, such as PCF1 sends a subscription request to NWDAF, the subscription request is used to obtain network performance indicator events, the network performance indicator event is an event in which the network performance indicator is lower than or restored to the preset threshold during the time window of the established background data transmission strategy (such as background data transmission strategy 3 formulated according to decision information 1); PCF1 receives the network performance indicator event notified by NWDAF.

[0260] At this point, PCF1 has formulated background data transmission strategy 3 corresponding to Reference Id1, and saved background data transmission strategy 3 and decision information 1 in the UDR.

[0261] S702: PCF1 sends message 2 to the UDR network element.

[0262] Among them, message 2 can be the data management service_query request (Nudr_DM_queryreqeust) provided by the Nudr interface. Message 2 is used to request all background data transmission strategies saved by the UDR network element. Message 2 can carry the reference identifier assigned by PCF1 to the background data transmission strategy 1: reference Id1 and the above-mentioned received decision information 1.

[0263] The present application is not limited to carrying reference Id1 and decision information 1 in message 2 and sending it to UDR. PCF1 can also send reference Id1 and decision information 1 to UDR through other messages. In this case, PCF1 first sends message 2 to UDR, requesting the background data transmission policy saved by UDR. UDR sends the saved background data transmission policy and corresponding decision information to PCF1, including background data transmission policy 3 and decision information 1 used to decide background data transmission policy 3 (also used to decide background data transmission policy 1) (at this time, decision information 1 does not include an indication that background data transmission policy 1 is being negotiated or the reason for formulating background data transmission policy 1). When PCF1 determines that background data transmission policy 1 needs to be re-formulated, PCF1 sends the updated decision information 1 to UDR through other messages.

[0264] Among them, the decision information 1 sent by PCF1 to UDR includes one or more information such as the number of first terminals, the first time window, the first network area information, the first traffic volume when each terminal transmits background data, or the reason for formulating the background data transmission strategy 1 (this information can be stored locally by PCF1 or obtained from UDR), and can also include: an indication that the background data transmission strategy is being formulated (i.e., negotiated). For example, PCF1 can carry decision information 1 through a special information element to indicate that the background data transmission strategy corresponding to reference Id1 is being negotiated, or include a special identifier in decision information 1 to indicate that the background data transmission strategy corresponding to reference Id1 is being negotiated, or use the reason for formulating the background data transmission strategy in decision information 1 to indicate that the background data transmission strategy corresponding to reference Id1 is being negotiated.

[0265] S703: The UDR network element receives message 2 and returns all background data transmission policies saved by the UDR network element to PCF1.

[0266] Furthermore, the UDR network element correspondingly stores decision information 1 and reference Id1.

[0267] It should be noted that, if the UDR network element stores decision information required by other PCFs in formulating background data transmission strategies, the UDR network element also returns the decision information stored in the UDR network element.

[0268] S704: PCF1 receives all background data transmission strategies saved by the UDR network element, and formulates one or more candidate background data transmission strategies according to all background data transmission strategies saved by the UDR network element, the current network status, operator strategies, etc.

[0269] The candidate background data transmission strategies are some background data transmission strategies that may be selected by AF1 as background data transmission strategy 1. A candidate background data transmission strategy may include one or more information such as strategy identifier, recommended transmission time window, maximum aggregate bit rate, and charging group identifier.

[0270] Exemplarily, the process of PCF1 formulating one or more candidate background data transmission strategies according to all background data transmission strategies saved by the UDR network element and the current network status, operator strategy, etc. can refer to the existing technology and will not be described in detail.

[0271] Furthermore, after PCF1 formulates one or more candidate background data transmission strategies, it executes Figure 1 As shown in S106 to S113, during the process of PCF1 executing S106 to S113, other PCFs may also formulate background data transmission strategies, such as PCF2, which means that two or more PCFs may formulate background data transmission strategies at the same time. Specifically, the process is shown in the following steps:

[0272] S705: PCF2 determines that the network performance indicator is lower than or restored to a preset threshold.

[0273] At this point, PCF2 has formulated background data transmission strategy 4 corresponding to Reference Id2, and saved background data transmission strategy 4 and decision information 2 in the UDR.

[0274] Among them, S705 can refer to S701 and will not be described in detail.

[0275] It should be noted that S705 may also be replaced by a process in which AF2 requests PCF2 to formulate a background data transmission strategy, such as the above-mentioned S606 to S607.

[0276] S706: PCF2 sends message 4 to the UDR network element.

[0277] S707: The UDR network element receives message 4 and returns all existing background data transmission policies and decision information 1 received in S703 to PCF2.

[0278] The UDR carries decision information 1 through a special cell to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or includes a special identifier in the decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or uses the reason for formulating background data transmission policy 1 in the decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated.

[0279] S708 : PCF2 determines that decision information 1 affects the formulation of background data transmission strategy 2 .

[0280] Furthermore, PCF2 does not delay formulating background data transmission strategy 2, but formulates background data transmission strategy 2 based on decision information 2, decision information 1 and all existing background data transmission strategies. However, the execution of background data transmission strategy 1 and background data transmission strategy 2 do not affect each other, such as the time windows of background data transmission strategy 1 and background data transmission strategy 2 are set to be non-overlapping and / or the maximum transmission rate of background data transmission strategy 1 and background data transmission strategy 2 when they are executed simultaneously in the network intersection area (such as the same area) will not exceed the preset threshold of the network performance indicator set by the operator, etc.

[0281] Alternatively, PCF2 delays the decision, for example, after PCF2 obtains background data transmission policy 1 in subsequent S715, it formulates background data transmission policy 2 based on decision information 2, all background data transmission policies stored in the UDR network element, and background data transmission policy 1. As described below, after receiving background data transmission policy 1 from the UDR network element, PCF2 may formulate background data transmission policy 2 based on decision information 2, all background data transmission policies stored in the UDR network element, and background data transmission policy 1.

[0282] Alternatively, PCF2 delays the decision, and after receiving the subsequent indication in S715 that the decision information 1 sent by the UDR has been deleted, PCF2 formulates background data transmission policy 2 based on the decision information 2 and all background data transmission policies saved by the UDR. For example, in the process of executing the following S709 to S714, PCF1 fails to negotiate background data transmission policy 1 with the third-party application server, and PCF1 sends an indication to the UDR to delete the decision information 1 (i.e., an indication to delete background data transmission policy 1), instructing the UDR to delete the decision information 1, and the UDR instructs PCF2 to delete the decision information 1. After receiving the indication from the UDR, PCF2 formulates background data transmission policy 2 based on the decision information 2 and all background data transmission policies saved by the UDR.

[0283] S709: PCF1 formulates one or more candidate background data transmission strategies according to decision information 1, all existing background data transmission strategies, current network status and operator strategy, and sends confirmation message 1 to NEF.

[0284] The decision information 1 is obtained by PCF1 from the UDR, or may be locally stored by PCF1 when AF1 requests the background data transmission policy from PCF1.

[0285] S710: NEF receives confirmation message 1 and returns notification message 1 to AF1.

[0286] S711: AF1 receives notification message 1. If AF1 decides to select one of the background data transmission strategies from one or more candidate background data transmission strategies as background data transmission strategy 1, AF1 carries reference Id1 and the policy identifier of the selected background data transmission strategy 1 in the update request 1 sent to NEF; if AF1 rejects all candidate background data transmission strategies, AF1 carries a rejection indication in the update request 1 sent to NEF.

[0287] S712: NEF receives update request 1 and sends update request 1 to PCF1.

[0288] S713: PCF1 receives update request 1 and sends update request 2 to the UDR network element.

[0289] The update request 2 may be a Nudr_DM_Update Request.

[0290] Exemplarily, PCF1 may send update request 2 to the UDR based on the content in update request 1. For example, if update request 1 carries reference Id1 and the policy identifier of the selected background data transmission policy 1, then update request 2 carries reference Id1 and the selected background data transmission policy 1; if update request 1 carries a rejection indication, then the update request may carry reference Id1 and a deletion indication, and the deletion indication may be used to instruct deletion of the decision information and / or background data transmission policy corresponding to reference Id1.

[0291] S714: The UDR network element receives the update request 2 and returns a response to the update request 2 to PCF1.

[0292] Furthermore, when update request 2 carries reference Id1 and a new background data transmission policy 1, the UDR network element updates background data transmission policy 3 corresponding to reference Id1 to background data transmission policy 1. Furthermore, the UDR deletes the indication that a background data transmission policy is being formulated or the reason for formulating the background data transmission policy from decision information 1; or, when update request 2 carries reference Id1 and a deletion indication, the UDR deletes decision information 1 and / or background data transmission policy 3 corresponding to reference Id1.

[0293] S715: Based on the fact that PCF2 has previously subscribed to the event notification of background data transmission policy change from the UDR network element, the UDR network element sends the background data transmission policy 1 or sends the reference Id1 and a deletion indication to PCF2.

[0294] S716: PCF2 receives the background data transmission policy 1 or reference Id1 and the deletion indication, and returns a response message to the UDR network element.

[0295] S717: PCF2 formulates one or more candidate background data transmission strategies for AF2 based on decision information 2, all existing background data transmission strategies (including background data transmission strategy 1), the current network status and the operator strategy; or formulates one or more candidate background data transmission strategies for AF2 based on decision information 2, all existing background data transmission strategies (excluding background data transmission strategy 3), the current network status and the operator strategy.

[0296] S718: PCF2 sends a confirmation message 2 to NEF.

[0297] S719: NEF receives the confirmation message 2 and returns a notification message 2 to AF2.

[0298] The notification message may carry Reference Id2 and one or more candidate background data transmission strategies.

[0299] S720: AF2 receives the notification message 2, selects one background data transmission policy from one or more candidate background data transmission policies as background data transmission policy 2, and sends an update request 3 to the NEF.

[0300] S721: NEF receives update request 3 and sends update request 3 to PCF2.

[0301] S722: PCF2 receives update request 3 and sends update request 4 to the UDR network element.

[0302] The update request 4 may be a Nudr_DM_Update Request. If the update request 3 carries reference ID 2 and the selected background data transmission policy 2, then the update request 4 carries reference ID 2 and the selected background data transmission policy 2. If the update request 3 carries a rejection indication, then the update request 4 carries reference ID 2 and a deletion indication. The deletion indication may be used to instruct deletion of the decision information 2 and / or background data transmission policy 2 corresponding to the reference ID 2.

[0303] S723: The UDR network element receives the update request 4 and returns a response to the update request 4 to PCF2.

[0304] Furthermore, when update request 4 carries reference ID 2 and background data transmission policy 2, the UDR network element updates background data transmission policy 4 corresponding to reference ID 2 to background data transmission policy 2. In addition, the UDR deletes the indication that a background data transmission policy is being formulated or the reason for formulating the background data transmission policy from decision information 2; or, when update request 2 carries reference ID 2 and a deletion indication, the UDR deletes decision information 2 corresponding to reference ID 2 and / or the stored background data transmission policy 4.

[0305] The execution process of the above S706 to S723 may refer to the description of S608 to S625, and will not be described in detail.

[0306] based on Figure 7 According to the method shown, multiple PCFs can re-formulate background data transmission strategies when network performance indicators are low or return to normal values. When formulating background data transmission strategies, they not only refer to existing background data transmission strategies, but also refer to the decision information required for other PCFs to formulate background data transmission strategies, so as to avoid conflicts between their own formulated background data transmission strategies and the background data transmission strategies formulated by other PCFs, thereby ensuring the availability of background data transmission strategies.

[0307] It should be noted that Figure 6 or Figure 7 The method shown can be applied to Figure 3a The 5G communication system shown is similar to Figure 6 or Figure 7 The method shown can also be applied to Figure 3b The 4G communication system shown in FIG. Figure 6 or Figure 7 After the PCF in the method shown is replaced by PCRF, the UDR network element is replaced by SPR, and the NEF is replaced by SCEF, Figure 6 or Figure 7The method shown can be applied to Figure 3b The 4G communication system shown.

[0308] The above mainly introduces the solution provided by the embodiment of the present application from the perspective of the interaction between each node. It can be understood that, in order to implement the above functions, each node, such as the first policy control network element, includes a hardware structure and / or software module corresponding to the execution of each function. Those skilled in the art should easily realize that, in combination with the algorithm steps of each example described in the embodiments disclosed herein, the method of the embodiment of the present application can be implemented in the form of hardware, software, or a combination of hardware and computer software. Whether a function is executed in a hardware or computer software-driven hardware manner depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0309] In the embodiment of the present application, the first policy control network element can be divided into functional modules according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. In actual implementation, there may be other division methods.

[0310] Figure 8 The structure diagram of a communication device 80 is shown. The communication device 80 can be a first policy control network element, a chip in the first policy control network element, a system on chip, or other devices capable of implementing the functions of the first policy control network element in the above method. The communication device 80 can be used to perform the functions of the first policy control network element involved in the above method embodiment. As an implementation method, Figure 8 The communication device 80 shown includes: a sending unit 801, a receiving unit 802, and a processing unit 803;

[0311] The sending unit 801 is configured to send a first message to a first network element, where the first message is used to request the background data transmission policy stored by the first network element. For example, the sending unit 801 is configured to support the communication device 80 in executing S501, S608, and S706.

[0312] The receiving unit 802 is configured to obtain the background data transmission policy and second decision information stored by the first network element from the first network element, where the second decision information is used to formulate the second background data transmission policy. For example, the receiving unit 802 is configured to support the communication device 80 in executing S502, S609, and S707.

[0313] The processing unit 803 is configured to formulate a first background data transmission policy based on the first decision information, the second decision information, and the background data transmission policy stored by the first network element, wherein the first decision information is used to formulate the first background data transmission policy. For example, the processing unit 803 is configured to support the communication device in executing S503, S619, and S717.

[0314] In one possible implementation, the processing unit 803 is specifically used to not delay the formulation of the first background data transmission strategy when the second decision information affects the decision / formulation of the first background data transmission strategy, but to formulate the first background data transmission strategy based on the first decision information, the second decision information and the background data transmission strategy saved by the first network element. However, the execution of the first background data transmission strategy and the second background data transmission strategy do not affect each other.

[0315] In another possible implementation, the processing unit 803 is specifically used to delay the formulation of the first background data transmission strategy when the second decision information affects the decision / formulation of the first background data transmission strategy, such as after obtaining the second background data transmission strategy, formulating the first background data transmission strategy based on the first decision information, the second background data transmission strategy and the background data transmission strategy saved by the first network element.

[0316] Optionally, before the sending unit 801 sends the first message to the first network element, the receiving unit 802 is also used to receive first decision information from the first application server, such as the receiving unit 802 receives a second message from the first application server, the second message includes the first decision information, and the second message is used to request the formulation of a first background data transmission strategy.

[0317] In one possible implementation, the sending unit 801 is specifically used to send the first message to the first network element based on the second message. For example, the second message is a trigger condition for the sending unit 801 to send the first message. Once the receiving unit 802 receives the second message, the sending unit 801 sends the first message to the first network element.

[0318] In another possible design, the sending unit 801 is specifically used to send a first message to the first network element when the network performance indicator is lower than or returns to a preset threshold. The network performance indicator may refer to the performance indicator of the network when transmitting background data according to a third background data transmission strategy. The third background data transmission strategy may be a background data transmission strategy formulated according to the first decision information before formulating the first background data transmission strategy.

[0319] Furthermore, the first message may include a first reference identifier and a first decision information, so that the first network element can save the first reference identifier and the first decision information accordingly, and provide the first decision information to other policy control network elements when other policy control network elements formulate background data transmission policies, so as to avoid conflicts between the background data transmission policies formulated by other policy control network elements and the background data transmission policies corresponding to the first decision information.

[0320] Specifically, the above Figure 5-Figure 7 All relevant contents of each step involved in the embodiment of the method shown can be referred to the functional description of the corresponding functional module, and will not be repeated here. Figure 5-Figure 7 In the method for formulating a background data transmission strategy shown in the method, the first strategy controls the function of the network element, and thus can achieve the same effect as the above method for formulating a background data transmission strategy.

[0321] In this embodiment, the communication device 80 can also be presented in the form of dividing various functional modules in an integrated manner. The "functional module" here can refer to an application specific integrated circuit (ASIC), a circuit, a processor and memory that executes one or more software or firmware programs, an integrated logic circuit, and / or other devices that can provide the above functions. In a simple embodiment, those skilled in the art can imagine that the communication device 80 can be presented in the form of Figure 4 The form of the communication device 400 is shown.

[0322] for example, Figure 4 The processor 401 in the communication device 400 shown may call the computer-executable instructions stored in the memory 404 to enable the communication device 400 to execute the method for formulating a background data transmission strategy in the above method embodiment.

[0323] Specifically, Figure 8 The functions / implementation processes of the sending unit 801 and the receiving unit 802 can be realized by Figure 4 The processor 401 in the communication device 400 is implemented by calling computer execution instructions stored in the memory 404 . Figure 8 The functions / implementation processes of the sending unit 801 and the receiving unit 802 can be realized by Figure 4 The communication interface 403 in the communication device 400 shown in FIG. Figure 8 The function / implementation process of the processing unit 803 can be achieved by Figure 4 The processor 401 in the communication device 400 shown in FIG. 1 is implemented.

[0324] The above embodiment introduces a solution for avoiding conflicts in background data transmission policies formulated by different PCFs when a network performance indicator falls below or recovers to a preset threshold and the PCF triggers the PCF to reformulate (i.e., renegotiate) the background data transmission policy, or when an application server triggers the PCF to formulate a background data transmission policy. In the process of formulating a background data transmission policy, in addition to considering conflicts between background data transmission policies formulated by different PCFs, it is also necessary to consider whether the background data transmission policy being formulated (i.e., negotiated) by the PCF will affect the formulation of other UE policies, such as the formulation of the UE policy and the UE session management policy of the UE.

[0325] In order to avoid the influence of the background data transmission strategy being formulated (ie negotiated) by the PCF on the formulation of other UE strategies, such as the session management strategy of the UE session, the present application also provides Figure 9 The session management scheme shown.

[0326] The following describes the session management solution provided in the embodiments of the present application in conjunction with the accompanying drawings.

[0327] The session management method provided in the embodiment of the present application can be used to Figure 9 The network shown, such as Figure 9 As shown, a communication system 10 provided in an embodiment of the present application is provided. The communication system 10 includes a second policy control network element and a first network element.

[0328] In the first implementation:

[0329] The second policy control network element can be used to formulate policies and charging control rules (PCC) such as background data transmission policy, service quality (quality of service) policy, slice selection policy, etc., and provide the formulated policies to network elements such as mobility management network element and session management network element.

[0330] The first network element may be called a network storage network element, and is used to store user data, such as user contract information, authentication or authorization data, etc. Specifically, the network storage network element may be a UDM network element, an NRF network element, or a UDR network element.

[0331] In one example, the second policy control network element is configured to receive a policy association establishment request corresponding to a session establishment request of a user equipment UE, and send a fourth message to the first network element for requesting a first background data transmission policy applied to the session.

[0332] The first network element is configured to receive the fourth message and send first decision information to the second policy control network element.

[0333] The second policy control network element is further configured to obtain first decision information corresponding to the first background data transmission policy from the first network element, and manage the session according to the first decision information.

[0334] In one possible design, the second policy control network element managing the session according to the first decision information includes:

[0335] The second policy control network element is specifically configured to reject the request for establishing a policy association according to the first decision information, or accept the request for establishing a policy association according to the first decision information.

[0336] Furthermore, when the second policy control network element accepts a request to establish a policy association based on the first decision information, the second policy control network element is also used to receive the first background data transmission policy corresponding to the first decision information sent by the first network element, formulate a session management policy for the session for performing policy billing control on the session based on the first background data transmission policy, and send the session management policy for the session to the session management network element.

[0337] In one possible design, the second policy control network element is further used to terminate the policy association according to the first background data transmission policy after receiving the first background data transmission policy sent by the first network element.

[0338] In one possible design, the second policy control network element is also used to terminate the policy association after receiving a deletion indication corresponding to the first decision information.

[0339] In the second implementation:

[0340] The second policy control network element is configured to receive a policy association establishment request corresponding to a registration request of the user equipment, and send a fourth message to the first network element for requesting a first background data transmission policy applied to the UE.

[0341] The first network element is configured to receive the fourth message and send first decision information to the second policy control network element.

[0342] The second policy control network element is further configured to obtain first decision information corresponding to the first background data transmission policy from the first network element, and formulate a UE policy for the UE according to the first decision information.

[0343] The second policy control network element formulating a UE policy for the UE according to the first decision information may include:

[0344] The second policy control network element is specifically configured to delay formulating a UE policy for the UE, and formulate a UE policy for the UE according to the first background data transmission policy after acquiring the first background data transmission policy corresponding to the first decision information.

[0345] In one possible design, the second policy control network element is also used for the second policy control network element to send a policy association establishment response, and the policy association establishment response does not carry the UE policy of the UE.

[0346] It should be noted that Figure 9 This is just an example architecture diagram. Figure 9 In addition to the functional units shown in , the system may also include other functional network elements, such as: a first policy control network element, etc., which is not limited in the embodiment of the present application. Figure 9 The names of the devices in the Figure 9 In addition to the names shown, each device can also be named other names, such as replacing them with network element names with the same or similar functions, without restriction.

[0347] The first policy control network element is used to send the first decision information to the first network element.

[0348] in, Figure 9 The communication system shown may be a 3rd Generation Partnership Project (3GPP) communication system, such as Figure 9 Can be Figure 3b The 4th generation (4G) communication system and the long term evolution (LTE) system shown in FIG. Figure 3a The fifth generation (5G) communication system or new radio (NR) system, next-generation communication system, etc. shown may also be a non-3GPP communication system without restriction.

[0349] Optionally, the second policy control network element in the embodiment of the present application may also be referred to as a communication device, which may be a general device or a dedicated device, and the embodiment of the present application does not specifically limit this.

[0350] Optionally, the relevant functions of the second policy control network element in the embodiment of the present application can be implemented by a single device, or by multiple devices together, or by one or more functional modules within a single device, and the embodiment of the present application does not specifically limit this. It is understandable that the above functions can be network elements in hardware devices, or software functions running on dedicated hardware, or a combination of hardware and software, or virtualized functions instantiated on a platform (e.g., a cloud platform).

[0351] In the specific implementation, Figure 9 Each device shown (such as the second policy control network element, etc.) can use Figure 4 The structure shown, or including Figure 4 Parts shown.

[0352] The following combination Figure 9 The communication system shown in the figure describes the session management method provided by the embodiment of the present application. Each network element in the following embodiment may have Figure 4 The components shown are not described in detail here. It should be noted that the message names or parameter names in the messages exchanged between the various devices in the embodiment of the present application are only examples, and other names can also be used in specific implementations. For example, the formulation described in the embodiment of the present application can be replaced by terms such as decision-making and negotiation. The determination in the embodiment of the present application can also be understood as creation (create) or generation (generate), and the "include" in the embodiment of the present application can also be understood as "carrying", and the "formulation" in the embodiment of the present application can also be understood as "decision-making" or "determination", etc., which are uniformly explained here, and the embodiment of the present application does not make specific limitations on this.

[0353] like Figure 10 As shown, a session management method provided in an embodiment of the present application may include:

[0354] S1001: A second policy control network element receives a request for establishing a policy association.

[0355] Among them, the second policy control network element can be Figure 2 Any policy control network element in the communication system shown.

[0356] The policy association establishment request may correspond to a session establishment request for a user equipment (UE). The policy association establishment request may be replaced by a session management policy association establishment request, which is used to request the establishment of a session management policy for the UE's session. The session management policy for the UE's session is used to perform policy charging control on the session. The session management policy may include at least policy charging control rules, which may be used to specify relevant performance parameters of a PDU session established by the UE for transmitting background data, such as quality of service (QoS) parameters and maximum rate of the PDU session.

[0357] Among them, the UE's session establishment request is used to request the establishment of the UE's session. For example, in a 5G communication system, the UE's session establishment request can be a UE's protocol data unit (PDU) session establishment request, and the UE's session can be a UE's PDU session.

[0358] Exemplarily, the second policy control network element may receive a policy association establishment request from a session management network element (such as SMF).

[0359] S1002: The second policy control network element sends a fourth message to the first network element. Correspondingly, the first network element receives the fourth message.

[0360] The first network element may be a UDR network element, a UDM network element, an NRF network element, or other network elements capable of storing background data transmission policies, etc. The description of the first network element may refer to that in S501 and will not be repeated here.

[0361] Among them, the fourth message can be used to request the background data transmission policy corresponding to the first reference identifier applied to the UE saved by the first network element. The background data transmission policy corresponding to the first reference identifier can be the background data transmission policy that needs to be obtained for formulating the first policy, that is, the background data transmission policy corresponding to the first reference identifier is associated with the formulation of the first policy, and it is possible that the background data transmission policy corresponding to the first reference identifier needs to be referred to when formulating the first policy. Previously, the first policy control network element negotiated with the first application server with reference to the above embodiment, formulated a third background data transmission policy corresponding to the first reference identifier based on the first decision information, and saved it in the first network element. Subsequently, the first policy control network element decided to re-formulate the background data transmission policy corresponding to the first reference identifier (that is, the first background data transmission policy) due to the reasons described in the above embodiment. The first background data transmission policy is an unfinished or being formulated (that is, negotiated) background data transmission policy, and the third background data transmission policy is an invalid background data transmission policy.

[0362] Illustratively, the fourth message may include a first reference identifier, which may be used to identify the first background data transmission policy and the third background data transmission policy, where the third background data transmission policy is an old background data transmission policy, and the first background data transmission policy may be a newly formulated background data transmission policy. The first reference identifier may also be used to identify first decision information corresponding to the first background data transmission policy.

[0363] S1003: The first network element sends first decision information to the second policy control network element according to the fourth message. Correspondingly, the second policy control network element obtains the first decision information from the first network element.

[0364] Among them, the first decision information may include one or more information such as the number of first terminals, the first time window, the first network area information, the first traffic when each terminal transmits background data, an indication that the first background data transmission strategy is being negotiated, or the reason for formulating the first background data transmission strategy. The first network element may carry the first decision information through a special information element to indicate that the background data transmission strategy is being formulated (i.e., negotiated), or include a special identifier in the first decision information to indicate that the background data transmission strategy is being formulated (i.e., negotiated), or use the reason for formulating the background data transmission strategy in the first decision information to indicate that the background data transmission strategy is being formulated (i.e., negotiated). Exemplarily, the process of the first network element sending the first decision information saved by the first network element to the second policy control network element can be referred to as described in S502 and will not be repeated here.

[0365] S1004: The second policy control network element manages the UE session according to the first decision information.

[0366] Exemplarily, the second policy control network element may determine whether the first decision information affects the formulation of the UE's session management policy. If the first decision information does not affect the formulation of the UE's session management policy, the second policy control network element may manage the UE's session with reference to an existing method. If the first decision information affects the formulation of the UE's session management policy, the second policy control network element may manage the UE's session using the following method 1 or method 2. The first decision information affecting the formulation of the UE's session management policy may include one or more of the following situations: for example, determining, based on the network policy configured by the operator, that the first background data transmission policy is not considered.

[0367] Method 1: The second policy control network element rejects the request to establish the policy association according to the first decision information, and stops formulating the session management policy for the UE.

[0368] Method 2: The second policy control network element accepts the request to establish a policy association according to the first decision information.

[0369] Furthermore, under the second method, the second policy control network element delays the formulation of the first policy until the second policy control network element obtains the first background data transmission policy corresponding to the first decision information, formulates the session management policy of the UE session according to the first background data transmission policy, sends the session management policy of the session to the session management network element, and triggers the session management network element to establish the UE session. Or,

[0370] Furthermore, in the second mode, when the first background data transmission policy is formulated, after the second policy control network element obtains the first background data transmission policy, if the first background data transmission policy conflicts with the UE session, the policy association is terminated according to the first background data transmission policy. Or,

[0371] Furthermore, under method two, if the negotiation of the first background data transmission policy fails, such as the first application server rejects the background data transmission policy generated by the first policy control network element, sends a rejection indication to the first policy control network element, the first policy control network element sends a first reference identifier and a deletion indication to the first network element, the first network element sends a deletion first reference identifier and a deletion indication to the second policy control network element, and the second policy control network element terminates the policy association after receiving the deletion indication.

[0372] In the embodiment of the present application, the second policy control network element terminating the policy association may refer to the second policy control network element sending a termination request message to the session management network element, where the termination request message is used to indicate the termination of the policy association.

[0373] It should be noted that, in the case where the second policy control network element obtains the first background data transmission policy or obtains a deletion indication from the first network element, the method further includes: the second policy control network element subscribes to a first event from the first network element, the first event being an event notification of a change in the background data transmission policy / decision information stored by the first network element, so that when the stored background data transmission policy changes, the first network element notifies the second policy control network element of the changed background data transmission policy, or notifies the second policy control network element of all background data transmission policies after the change in the first network element, or notifies the second policy control network element of the change in decision information. Among them, the change in background data transmission policy may include adding, deleting, or updating the background data transmission policy, etc. The change in decision information may include deleting decision information, or updating the content included in the decision information, or adding new decision information, etc.

[0374] based on Figure 10 According to the method shown, when the policy control network element formulates the session management policy for the UE's session, it can obtain the decision information required for formulating other policies for the UE from the first network element, and manage the session with reference to the obtained decision information, so as to avoid the problem that the formulated decision information corresponds to the background data transmission policy and the session management policy for the UE's session, thereby ensuring the availability of the background data transmission policy and other policies of the UE.

[0375] In addition to managing the UE's session according to the decision information, the second policy control network element can also formulate other policies of the UE in addition to the background data transmission policy, such as UE policy, etc., according to the decision information, to avoid conflicts between the UE's other policies in addition to the background data transmission policy and other policies, resulting in background data transmission failure. Among them, taking the formulation of the UE policy of the UE according to the decision information as an example, the method for the second policy control network element to formulate the UE policy of the UE according to the decision information can be referred to Figure 10 As shown, it can include the following (1) to (4):

[0376] (1) The second policy control network element receives a policy association establishment request corresponding to a registration request of a user equipment.

[0377] The policy association establishment request corresponding to the registration request of the user equipment may be a UE policy association establishment request, for requesting to establish a UE policy. The UE policy may be used to instruct the UE to establish a PDU session for transmitting background data.

[0378] The registration request may request to register with the network.

[0379] Exemplarily, the second policy control network element may receive a policy association establishment request corresponding to a registration request of the user equipment from the session management network element.

[0380] (2) The second policy control network element sends a fourth message to the first network element for requesting the first background data transmission policy to be applied to the UE. This step is the same as S1002 and will not be described in detail.

[0381] (3) The second policy control network element obtains first decision information corresponding to the first background data transmission policy from the first network element. This step is the same as S1003 and will not be described in detail.

[0382] (4) The second policy control network element formulates a UE policy for the UE according to the first decision information.

[0383] Exemplarily, the second policy control network element may delay formulating the UE policy for the UE, and formulate the UE policy for the UE according to the first background data transmission policy after acquiring the first background data transmission policy corresponding to the first decision information.

[0384] Optionally, the second policy control network element sends a policy association establishment response, and the policy association establishment response does not carry the UE policy of the UE, such as the second policy control network element sends a policy association establishment response that does not carry the UE policy to the session management network element.

[0385] In this way, when formulating the UE policy for the UE, the policy control network element can obtain the decision information required for formulating other policies for the UE from the first network element, and formulate the UE policy with reference to the obtained decision information, thereby avoiding the problem of conflicts between the background data transmission policy and the UE policy corresponding to the formulated decision information, and ensuring the availability of the background data transmission policy and the UE policy.

[0386] The following combination Figure 3aIn the 5G communication system shown, the policy control network element is PCF (such as the first policy control network element is PCF2, the second policy control network element is PCF1), the application server is AF (such as the first application server is AF2, the second application server is AF1), the first network element is UDR network element, the first background data transmission policy is background data transmission policy 1, the first decision information is decision information 1, PCF1 updates or renegotiates background data transmission policy 1, PCF2 formulates UE policy and UE session management policy as an example. Figure 10 The method shown is introduced. Figure 3a Not shown, but Figure 3a The 5G communication system shown may also include: access and mobility management function (AMF), session management function (SMF) and other network elements, without restriction.

[0387] Figure 11 A flow chart of a method for formulating UE policy and session management policy based on background data transmission policy provided in an embodiment of the present application is as follows: Figure 11 As shown, the method may include:

[0388] S1101: PCF1 determines that a network performance indicator is lower than or restored to a preset threshold.

[0389] The preset threshold can be set as needed and is not restricted. For example, after a transmission window is allocated, if the network changes and the network load becomes relatively congested during that period, the rate will also become higher, resulting in high user transmission rates and failing to meet the user's need for network transmission at the lowest cost. In other words, the network performance indicator falls below the preset threshold.

[0390] Exemplarily, PCF1 can determine by itself whether the network performance indicator is lower than or restored to the preset threshold; or, PCF1 can learn from other network elements whether the network performance indicator is lower than or restored to the preset threshold, such as PCF1 sends a subscription request to NWDAF, the subscription request is used to obtain network performance indicator events, the network performance indicator event is an event in which the network performance indicator is lower than or restored to the preset threshold during the time window of the established background data transmission strategy (such as background data transmission strategy 3 formulated according to decision information 1); PCF1 receives the network performance indicator event notified by NWDAF.

[0391] Before S1101 , PCF1 formulates background data transmission strategy 3 according to decision information 1 , and saves decision information 1 and background data transmission strategy 3 corresponding to referenceId1 in UDR.

[0392] S1102: PCF1 sends message 1 to the UDR network element.

[0393] Among them, message 1 can be the data management service _query request (Nudr_DM_queryreqeust) provided by the Nudr interface. Message 1 is used to request all background data transmission policies saved by the UDR network element. Message 1 can carry the reference identifier assigned by PCF1 to the background data transmission policy 3: reference Id1 and decision information 1. This application is not limited to carrying reference Id1 and decision information 1 in message 1 and sending it to the UDR network element. PCF1 can also send reference Id1 and decision information 1 to the UDR network element through other messages.

[0394] PCF1 can indicate that a background data transmission policy corresponding to reference ID 1 is being formulated by carrying decision information 1 in a special information element, or by including a special identifier in decision information 1 to indicate that a background data transmission policy corresponding to reference ID 1 is being formulated, or by using the reason for formulating the background data transmission policy in decision information 1 to indicate that a background data transmission policy corresponding to reference ID 1 is being formulated. The above information also indicates that background data transmission policy 3 is not a valid background data transmission policy.

[0395] S1103: The UDR network element receives message 1 and returns all background data transmission policies saved by the UDR network element to PCF1.

[0396] Furthermore, the UDR network element correspondingly stores decision information 1 and reference Id1.

[0397] It should be noted that, if the UDR network element stores decision information required by other PCFs in formulating background data transmission strategies, the UDR network element also returns the decision information stored in the UDR network element.

[0398] S1104: PCF1 receives all background data transmission strategies saved by the UDR network element, and formulates one or more candidate background data transmission strategies according to all background data transmission strategies saved by the UDR network element, the current network status, operator strategies, etc.

[0399] The candidate background data transmission strategies are some background data transmission strategies that may be selected by AF1 as background data transmission strategy 1. A candidate background data transmission strategy may include one or more information such as strategy identifier, recommended transmission time window, maximum aggregate bit rate, and charging group identifier.

[0400] Exemplarily, the process of PCF1 formulating one or more candidate background data transmission strategies according to all background data transmission strategies saved by the UDR network element and the current network status, operator strategy, etc. can refer to the existing technology and will not be described in detail.

[0401] Furthermore, after PCF1 formulates one or more candidate background data transmission strategies, it executes Figure 1 As shown in S116 to S113, during the process of PCF1 executing S116 to S113, other PCFs may need to formulate UE policies or session management policies based on the background data transmission policy. Specifically, the process is shown in the following steps:

[0402] S1105: The UE initiates a registration request to the AMF, and the AMF receives the registration request from the UE.

[0403] The registration request of the UE is used to request registration with the network.

[0404] S1106: The AMF sends a UE policy association establishment request to PCF2. PCF2 determines that the background data transmission policy corresponding to reference Id1 is required to formulate the UE policy based on the UE's subscription information, network policy, or obtained application data. The UE policy association between the AMF and PCF2 is used by PCF2 to provide the UE policy to the AMF for transmission to the UE.

[0405] S1107: PCF2 sends message 2 to the UDR network element.

[0406] Message 2 may be used to request a background data transmission policy corresponding to reference Id1, and message 2 may include reference Id1.

[0407] S1108: The UDR network element returns decision information 1 corresponding to reference Id1 to PCF2.

[0408] Among them, the UDR network element can carry a special information element through decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or include a special identifier in decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or use the reason for formulating background data transmission policy 1 in decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated.

[0409] Optionally, the UDR also returns background data transmission policy 3 to PCF 2. Decision information 1 indicates that background data transmission policy 3 has expired.

[0410] S1109: PCF2 determines that decision information 1 affects the formulation of UE policy.

[0411] Since decision information 1 indicates that the background data transmission policy corresponding to reference Id1 is being formulated or decision information 1 indicates that background data transmission policy 3 has expired, PCF2 does not decide / formulate the UE policy corresponding to background data transmission policy 3 based on decision information 1 or background data transmission policy 3, or delays deciding / formulating the UE policy corresponding to background data transmission policy 1 based on background data transmission policy 1.

[0412] S1110: PCF2 returns a UE policy association establishment response to the AMF.

[0413] The UE policy association establishment response does not carry the UE policy that needs to be formulated according to background data transmission policy 1 or background data transmission policy 3.

[0414] S1111: After the UE successfully registers, the UE sends a PDU session establishment request to the AMF, which then sends a PDU session establishment request to the SMF. The SMF receives the PDU session establishment request from the AMF.

[0415] S1112: The SMF sends a session management policy association establishment request to PCF2. PCF2 determines, based on the contract or network policy, that it needs to obtain the background data transmission policy corresponding to reference Id1 to formulate the session management policy. The session management policy association established between the SMF and PCF2 is used by PCF2 to provide the SMF with relevant policies for managing PDU sessions, such as PDU session-related policy information (including the maximum aggregate bit rate of the session, policy control request triggers, etc.) and policy charging rules. This enables the PCF to manage the PDU session.

[0416] S1113: PCF2 sends message 3 to the UDR network element to request a background data transmission strategy.

[0417] Message 3 includes reference Id1.

[0418] S1114: The UDR network element returns decision information 1 corresponding to reference Id1 to PCF2.

[0419] For example, the UDR network element carries a special information element through decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or includes a special identifier in decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated, or uses the reason for formulating the background data transmission policy in decision information 1 to indicate that the background data transmission policy corresponding to reference Id1 is being negotiated.

[0420] Optionally, the UDR returns background data transmission strategy 3 to PCF2.

[0421] S1115: PCF2 determines that decision information 1 affects the formulation of the UE session management policy.

[0422] Since decision information 1 indicates that the background data transmission policy corresponding to reference Id1 is being formulated or decision information 1 indicates that background data transmission policy 3 has expired, PCF2 does not decide the UE's session management policy based on decision information 1; or PCF2 decides to accept the session management policy association establishment request and delays deciding the UE's session management policy corresponding to the background data transmission policy based on decision information 1 or background data transmission policy 3; or PCF2 decides to reject the session management policy association establishment request.

[0423] S1116: PCF2 returns a session management policy association response message to SMF.

[0424] If PCF2 decides to delay the decision on the UE session management policy corresponding to the background data transmission policy based on decision information 1, PCF2 returns an acceptance indication or a success response indication to SMF; if PCF2 decides to reject the session management policy association establishment request, the session management policy association response message carries a rejection indication and a reason value. The rejection indication can be used to indicate the rejection of the session management policy association establishment request, and the reason value can be that the background data transmission policy is being renegotiated or the background data transmission policy is invalid.

[0425] Furthermore, the SMF sends a rejection indication and a cause value to the AMF, and the AMF further sends a rejection indication and a cause value to the UE. The SMF further returns a corresponding response message to the AMF.

[0426] S1117: PCF1 formulates one or more candidate background data transmission strategies according to decision information 1, all existing background data transmission strategies, current network status, and operator strategy, and sends confirmation message 1 to NEF.

[0427] S1118: NEF receives confirmation message 1 and returns notification message 1 to AF1.

[0428] S1119: AF1 receives notification message 1. If AF1 decides to select one of the background data transmission strategies from one or more candidate background data transmission strategies as background data transmission strategy 1, then AF1 sends an update request 1 to NEF carrying reference Id1 and the policy identifier of the selected background data transmission strategy 1. If AF1 rejects all candidate background data transmission strategies, then AF1 sends an update request 1 to NEF carrying a rejection indication.

[0429] S1120: NEF receives update request 1 and sends update request 1 to PCF1.

[0430] S1121: PCF1 receives update request 1 and sends update request 2 to the UDR network element.

[0431] The update request 2 may be a Nudr_DM_Update Request.

[0432] Exemplarily, PCF1 may send update request 2 to the UDR based on the content in update request 1. For example, if update request 1 carries reference Id1 and the policy identifier of the selected background data transmission policy 1, then update request 2 carries reference Id1 and the selected background data transmission policy 1; if update request 1 carries a rejection indication, then the update request may carry reference Id1 and a deletion indication, and the deletion indication may be used to instruct deletion of the decision information and / or background data transmission policy corresponding to reference Id1.

[0433] S1122: The UDR network element receives the update request 2 and returns a response to the update request 2 to PCF1.

[0434] Furthermore, when the update request 2 carries reference Id1 and background data transmission policy 1, the UDR network element updates the background data transmission policy corresponding to reference Id1 to background data transmission policy 1; or, when the update request 2 carries reference Id1 and a deletion indication, the decision information 1 corresponding to reference Id1 is deleted and / or the saved background data transmission policy 3 is deleted).

[0435] S1123: Based on the fact that PCF2 has previously subscribed to the event notification of background data transmission policy change from the UDR network element, the UDR network element sends a new background data transmission policy 1 or sends reference Id1 and a deletion indication to PCF2.

[0436] S1124: PCF2 receives background data transmission policy 1, or PCF2 receives reference Id1 and a deletion indication, and returns a response message to the UDR network element.

[0437] S1125: If PCF2 receives background data transmission policy 1, it formulates a corresponding UE policy based on background data transmission policy 1. PCF2 sends a UE policy provision message to the AMF, which includes the formulated UE policy. The AMF further sends the UE policy to the UE.

[0438] If PCF2 receives reference Id1 and a deletion instruction, PCF2 deletes decision information 1 and / or background data transmission policy 3 corresponding to reference Id1, and terminates the session management policy association establishment request.

[0439] S1126: If in step S1116, PCF2 returns an acceptance indication or a success response indication to SMF, and if a new background data transmission policy 1 is received, PCF2 formulates a corresponding UE session management policy according to the new background data transmission policy 1 or rejects the establishment of a PDU session according to the new background data transmission policy 1.

[0440] If PCF2 has formulated a corresponding UE session management policy, PCF2 sends the UE session management policy to SMF.

[0441] If PCF decides to reject the PDU session, PCF2 sends a rejection indication and a reason value to SMF. The reason value may be that the verification condition is not met or the policy authorization fails. Further, SMF sends the decision information to AMF.

[0442] If in step S1116, PCF2 returns an acceptance indication or a successful response indication to SMF, and if referenceId1 and a deletion indication are received, PCF2 sends a rejection indication and a reason value to SMF. The reason value may be that the verification condition is not met or the policy authorization fails, etc.

[0443] based on Figure 11 According to the method shown, when formulating UE policies or UE session management policies, PCF can refer to the background data transmission policies formulated by other PCFs or the decision information required for other PCFs to formulate background data transmission policies, so as to avoid conflicts between its own formulated UE policies or UE session management policies and the background data transmission policies formulated by other PCFs, and ensure the availability of its own formulated UE policies or UE session management policies.

[0444] Figure 12 The structure diagram of a communication device 120 is shown. The communication device 120 can be a second policy control network element, a chip in the second policy control network element, a system on chip, or other devices capable of implementing the functions of the second policy control network element in the above method. The communication device 120 can be used to perform the functions of the second policy control network element involved in the above method embodiment. As an implementation method, Figure 12 The communication device 120 shown includes: a sending unit 1201, a receiving unit 1202, and a processing unit 1203;

[0445] In the first implementation:

[0446] The receiving unit 1202 is configured to receive a policy association establishment request corresponding to a session establishment request of a user equipment UE. The receiving unit 1202 supports the communication device 120 to execute S1001.

[0447] The sending unit 1201 is configured to send a fourth message to the first network element, where the fourth message may be used to request a first background data transmission policy to be applied to the session. For example, the sending unit 1201 is configured to support the communication device 120 in executing S1002, S1107, and S1113.

[0448] The receiving unit 1202 is configured to obtain, from a first network element, first decision information stored by the first network element, where the first decision information corresponds to a first background data transmission policy. For example, the receiving unit 1202 is configured to support the communication device 120 in executing S1003.

[0449] The processing unit 1203 is configured to manage the session according to the first decision information. For example, the processing unit 1203 is configured to support the communication device in executing S1004, S1109, S1115, and S1126.

[0450] Among them, in this possible implementation, the processing unit 1203 is specifically used to accept the establishment request of the policy association according to the first decision information when the second decision information affects the decision / formulation of the first background data transmission policy. Further, after the second policy control network element receives the first background data transmission policy corresponding to the first decision information sent by the first network element, it formulates the session management policy of the session according to the first background data transmission policy and sends the session management policy of the session to the session management network element; or, after the second policy control network element receives the first background data transmission policy sent by the first network element, it terminates the policy association according to the first background data transmission policy; or, after the second policy control network element receives the first background data transmission policy sent by the first network element, it terminates the policy association according to the first background data transmission policy. Or,

[0451] The processing unit 1203 is specifically configured to reject the request for establishing a policy association according to the first decision information when the second decision information affects the decision / formulation of the first background data transmission policy.

[0452] In the second implementation:

[0453] The receiving unit 1202 is configured to receive a policy association establishment request, where the policy association establishment request corresponds to a registration request of a user equipment.

[0454] The sending unit 1201 is configured to send a fourth message to a first network element, where the fourth message is used to request a first background data transmission policy to be applied to the UE.

[0455] The receiving unit 1202 is further configured to obtain first decision information from the first network element, where the first decision information corresponds to a first background data transmission strategy.

[0456] The processing unit 1203 is configured to formulate a UE policy for the UE according to the first decision information.

[0457] In one possible design, the processing unit 1203 is specifically configured to delay formulating a UE policy for the UE, and after obtaining a first background data transmission policy corresponding to the first decision information, formulate a UE policy for the UE according to the first background data transmission policy.

[0458] In one possible design, the sending unit 1201 is also used for the second policy control network element to send a policy association establishment response, and the policy association establishment response does not carry the UE policy of the UE.

[0459] Specifically, the above Figure 10-11 All relevant contents of each step involved in the method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here. Figure 10-11 In the method for formulating a background data transmission strategy shown in the illustrated method, the second strategy controls the function of the network element, and thus can achieve the same effect as the above-mentioned method for formulating a background data transmission strategy.

[0460] In this embodiment, the communication device 120 can also be presented in the form of dividing various functional modules in an integrated manner. The "functional module" here can refer to an application specific integrated circuit (ASIC), a circuit, a processor and memory that executes one or more software or firmware programs, an integrated logic circuit, and / or other devices that can provide the above functions. In a simple embodiment, those skilled in the art can imagine that the communication device 120 can be presented in the form of Figure 4 The form of the communication device 400 is shown.

[0461] for example, Figure 4 The processor 401 in the communication device 400 shown may call the computer-executable instructions stored in the memory 404 to enable the communication device 400 to execute the method for formulating the background data transmission strategy in the above method embodiment.

[0462] Specifically, Figure 12 The functions / implementation processes of the sending unit 1201 and the receiving unit 1202 can be realized by Figure 4 The processor 401 in the communication device 400 is implemented by calling computer execution instructions stored in the memory 404 . Figure 12The functions / implementation processes of the sending unit 1201 and the receiving unit 1202 can be realized by Figure 4 The communication interface 403 in the communication device 400 shown in FIG. Figure 12 The function / implementation process of the processing unit 1203 can be achieved by Figure 4 The processor 401 in the communication device 400 shown in FIG. 1 is implemented.

[0463] The embodiments of the present application also provide a computer-readable storage medium. All or part of the processes in the above-mentioned method embodiments can be completed by a computer program to instruct the relevant hardware, and the program can be stored in the above-mentioned computer-readable storage medium. When the program is executed, it can include the processes of the above-mentioned method embodiments. The computer-readable storage medium can be a terminal device of any of the above-mentioned embodiments, such as: an internal storage unit including a data sending end and / or a data receiving end, such as a hard disk or memory of the terminal device. The above-mentioned computer-readable storage medium can also be an external storage device of the above-mentioned terminal device, such as a plug-in hard disk, a smart memory card (smart media card, SMC), a secure digital (secure digital, SD) card, a flash card (flash card), etc. equipped on the above-mentioned terminal device. Furthermore, the above-mentioned computer-readable storage medium can also include both the internal storage unit of the above-mentioned terminal device and an external storage device. The above-mentioned computer-readable storage medium is used to store the above-mentioned computer program and other programs and data required by the above-mentioned terminal device. The above-mentioned computer-readable storage medium can also be used to temporarily store data that has been output or is to be output.

[0464] The present application also provides a computer instruction. All or part of the process in the above method embodiment can be completed by the computer instruction to instruct the relevant hardware (such as a computer, processor, network device, and terminal, etc.). The program can be stored in the above computer-readable storage medium.

[0465] It should be understood that in the embodiments of the present application, "B corresponding to A" means that B is associated with A. For example, B can be determined based on A. It should also be understood that determining B based on A does not mean determining B based solely on A; B can also be determined based on A and / or other information. In addition, the "connection" in the embodiments of the present application refers to various connection methods, such as direct connection and indirect connection, to achieve communication between devices, and the embodiments of the present application do not impose any limitations on this.

[0466] Unless otherwise specified, the "transmission" (transmit / transmission) appearing in the embodiments of the present application refers to bidirectional transmission, including the actions of sending and / or receiving. Specifically, the "transmission" in the embodiments of the present application includes the sending of data, the receiving of data, or the sending of data and the receiving of data. In other words, the data transmission here includes uplink and / or downlink data transmission. Data may include channels and / or signals, uplink data transmission is uplink channel and / or uplink signal transmission, and downlink data transmission is downlink channel and / or downlink signal transmission. The "network" and "system" appearing in the embodiments of the present application express the same concept, and the communication system is the communication network.

[0467] In the description of this application, unless otherwise specified, " / " indicates that the objects associated with each other are in an "or" relationship. For example, A / B can mean A or B. "And / or" in this application is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, in the description of this application, unless otherwise specified, "multiple" means two or more than two. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple. In addition, to facilitate the clear description of the technical solutions of the embodiments of this application, in the embodiments of this application, words such as "first" and "second" are used to distinguish between identical or similar items with substantially the same functions and effects. Those skilled in the art will understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit differences. At the same time, in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or design. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete way for easy understanding.

[0468] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0469] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the modules or units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0470] The units described as separate components may or may not be physically separate, and the components shown as units may be one physical unit or multiple physical units, that is, they may be located in one place or distributed in multiple different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0471] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0472] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a device, such as a single-chip microcomputer, a chip, etc., or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

[0473] The above is only a specific embodiment of the present application, but the scope of protection of this application is not limited to this. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A method for formulating a background data transmission strategy, characterized in that: The method comprises: The first policy control network element determines that the network performance indicator is lower than a preset threshold within a first time window, where the first time window is a time window included in a first background data transmission policy, and the first background data transmission policy is a background data transmission policy corresponding to the first reference identifier; The first policy control network element obtains from the first network element all background data transmission policies saved by the first network element; The first policy control network element renegotiates the background data transmission policy corresponding to the first reference identifier according to all background data transmission policies stored by the first network element and the network performance; The first policy control network element sends a first message to the first network element, where the first message includes the first reference identifier and first decision information, where the first decision information is used to indicate that a background data transmission policy corresponding to the first reference identifier is being negotiated.

2. The method according to claim 1, characterized in that The first policy control network element renegotiating the first background data transmission policy corresponding to the first reference identifier according to all background data transmission policies and the network performance includes: The first policy control network element formulates at least one candidate background data transmission strategy according to all background data transmission strategies stored by the first network element and the network performance, and sends the at least one candidate background data transmission strategy and the first reference identifier to the first application function network element; The first policy control network element receives a policy identifier of a background data transmission policy selected by the first application function network element; The first policy control network element sends a second message to the first network element, where the second message includes the first reference identifier and the selected background data transmission policy.

3. The method according to claim 1, characterized in that The first policy control network element renegotiating the first background data transmission policy corresponding to the first reference identifier according to all background data transmission policies and the network performance includes: The first policy control network element formulates at least one candidate background data transmission strategy according to all background data transmission strategies stored by the first network element and the network performance, and sends the at least one candidate background data transmission strategy and the first reference identifier to the first application function network element; The first policy control network element receives a rejection indication sent by the first application function network element, where the rejection indication is used to instruct the first application function network element to reject all candidate background data transmission policies; The first policy control network element sends a deletion instruction and the first reference identifier to the first network element according to the rejection instruction, where the deletion instruction is used to instruct the first network element to delete the decision information and / or background data transmission policy corresponding to the first reference identifier.

4. A communication system, characterized in that: The communication system includes a first policy control network element and a first network element; The first policy control network element is used to determine that the network performance indicator is lower than a preset threshold within a first time window, the first time window is a time window included in the first background data transmission policy, and the first background data transmission policy is the background data transmission policy corresponding to the first reference identifier; The first policy control network element is further configured to obtain, from the first network element, all background data transmission policies stored by the first network element; and renegotiate the background data transmission policy corresponding to the first reference identifier according to all background data transmission policies stored by the first network element and the network performance; The first policy control network element is further used to send a first message to the first network element, where the first message includes the first reference identifier and first decision information, where the first decision information is used to indicate that a background data transmission policy corresponding to the first reference identifier is being negotiated.

5. The communication system according to claim 4, wherein: The first network element is further used to receive the first message from the first policy control network element and save the first decision information and the first reference identifier.

6. The communication system according to claim 5, characterized in that The first network element is further configured to receive a message from a second policy control network element for requesting the background data transmission policy saved by the first network element; The first network element sends all background data transmission policies, the first reference identifier, and the first decision information stored by the first network element to the second policy control network element.

7. The communication system according to claim 5, wherein: The first network element is further configured to receive a fourth message from a second policy control network element, where the fourth message includes the first reference identifier, and the fourth message is used to request a background data transmission policy corresponding to the first reference identifier applied to a user equipment UE; The first network element is further used to send the first decision information to the second policy control network element.

8. The communication system according to any one of claims 4 to 7, characterized in that: The first policy control network element is further configured to send the first reference identifier and the background data transmission policy renegotiated by the first policy control network element to the first network element; The first network element is further configured to receive the first reference identifier and the background data transmission policy renegotiated by the first policy control network element from the first policy control network element; The first network element is further configured to store the renegotiated background data transmission strategy.

9. The communication system according to claim 8, wherein: The first network element is further configured to send the renegotiated background data transmission policy to the second policy control network element.

10. A method for session management, characterized in that: The method comprises: The second policy control network element receives a policy association establishment request corresponding to the session establishment request of the user equipment UE; the second policy control network element sends a fourth message to the first network element, the fourth message including the first reference identifier, and the fourth message is used to request a background data transmission policy corresponding to the first reference identifier; The second policy control network element receives first decision information from the first network element, where the first decision information indicates that a background data transmission policy corresponding to the first reference identifier is being negotiated; The second policy control network element manages the session according to the first decision information.

11. The method according to claim 10, characterized in that The second policy control network element managing the session according to the first decision information includes: The second policy control network element rejects the request to establish the policy association according to the first decision information.

12. The method according to claim 10, characterized in that The second policy control network element managing the session according to the first decision information includes: The second policy control network element delays formulating a session management policy for managing the session according to the first decision information; After receiving the first background data transmission policy corresponding to the first reference identifier sent by the first network element, the second policy control network element formulates the session management policy according to the first background data transmission policy; The second policy control network element sends the session management policy to the session management network element.

13. The method according to claim 10, characterized in that The second policy control network element managing the session according to the first decision information includes: The second policy control network element delays formulating a session management policy for managing the session according to the first decision information; After receiving the first background data transmission policy corresponding to the first reference identifier sent by the first network element, the second policy control network element determines to terminate the session according to the first background data transmission policy; The second policy control network element sends an instruction to terminate the session to the session management network element.

14. A communication system, characterized in that: The communication system comprises: The second policy control network element is configured to receive a policy association establishment request corresponding to a session establishment request of a user equipment UE, and send a fourth message to the first network element, where the fourth message includes the first reference identifier and is used to request a background data transmission policy corresponding to the first reference identifier; The first network element is configured to receive the fourth message and send first decision information to the second policy control network element, where the first decision information indicates that a background data transmission policy corresponding to the first reference identifier is being negotiated; The second policy control network element is configured to receive the first decision information from the first network element, and manage the session according to the first decision information.

15. The communication system according to claim 14, wherein: The second policy control network element is specifically configured to reject the request to establish the policy association according to the first decision information.

16. The communication system according to claim 14, wherein: The second policy control network element is specifically configured to: delaying the formulation of a session management policy for managing the session according to the first decision information, After receiving the first background data transmission policy corresponding to the first reference identifier sent by the first network element, the session management policy is formulated according to the first background data transmission policy, and the session management policy is sent to the session management network element.

17. The communication system according to claim 14, wherein: The second policy control network element is specifically configured to: delaying formulating a session management policy for managing the session according to the first decision information; After receiving the first background data transmission policy corresponding to the first reference identifier sent by the first network element, determining to terminate the session according to the first background data transmission policy, and sending an instruction to terminate the session to the session management network element.

18. A communication device, characterized in that: include: memory for storing computer programs; A processor, configured to call and run the computer program from the memory to perform the method according to any one of claims 1 to 3 or any one of claims 10 to 13.

19. A processor, characterized in that: Used to perform the method according to any one of claims 1 to 3, or any one of claims 10 to 13.

20. A chip system, characterized in that: include: memory for storing computer programs; A processor, configured to call and run the computer program from the memory, so that a device equipped with the chip system executes the method according to any one of claims 1 to 3 or any one of claims 10 to 13.

21. A computer-readable storage medium comprising a computer program, characterized in that When the method is executed on a computer, the computer is enabled to execute the method according to any one of claims 1 to 3 or any one of claims 10 to 13.

22. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is run on a computer, the computer is caused to perform the method according to any one of claims 1 to 3 or any one of claims 10 to 13.

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