CN115707065A

CN115707065A - Communication method and device

Info

Publication number: CN115707065A
Application number: CN202110904205.2A
Authority: CN
Inventors: 李卓明; 丁辉
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-08-06
Filing date: 2021-08-06
Publication date: 2023-02-17
Also published as: WO2023010979A1

Abstract

The application provides a communication method and a device, and the method comprises the following steps: the policy decision function network element determines first policy information and sends the first policy information to a policy execution function network element, wherein the first policy information is used for the policy execution function network element to execute processing. The first policy information may include at least one of an access control rule of the network slice, a service processing parameter, or a charging key value corresponding to the network slice. The method can realize flexible control on the service of the access network slice.

Description

Communication method and device

Technical Field

The present application relates to the field of mobile communications technologies, and in particular, to a communication method and apparatus.

Background

A network slice (network slice) is a logical network with specific network characteristics, and is a key technology for meeting the requirements of a fifth generation (5g) mobile communication system on network differentiation proposed by the third generation partnership project (3 rd generation partnership project,3 gpp). A5G physical network can be abstractly divided into a plurality of network slices, and each network slice forms an end-to-end logic network which is logically isolated from each other and does not influence each other. Thus, a network slice is a logical network with specific network characteristics divided in the operator's communication network. The service of each network slice is identified using a single-network slice selection assistance information (S-NSSAI). And the 5G network selects a network slice for the service according to the S-NSSAI carried in the terminal service request, and transmits the service data of the client in the selected network slice.

In order to control the number of registered terminals or the number of Protocol Data Units (PDUs) sessions (sessions) accessed by a network slice, a Network Slice Access Control Function (NSACF) entity is introduced. When a terminal (UE) accesses a network slice through a registration request, an access and mobility management function (AMF) needs to inquire whether the number of existing registered terminals in the NSACF network slice has reached the maximum number of registered terminals. When a UE requests to establish a new PDU session in a network slice, a Session Management Function (SMF) needs to inquire whether the number of existing PDU sessions in an NSACF network slice has reached the maximum session establishment number. If it has, the AMF or SMF will reject the request to access this network slice.

At present, the above access management method for network slices is not flexible enough.

Disclosure of Invention

The application provides a communication method and a communication device, which are used for flexibly controlling the service of an access network slice.

In a first aspect, the present application provides a communication method, which may be performed by a policy decision function network element, or by a system-on-chip in the policy decision function network element, where the system-on-chip is capable of implementing a function of the policy decision function network element. Taking the 5G communication system as an example, the policy decision function network element may be a Policy Control Function (PCF). The method comprises the following steps: a policy decision function network element determines first policy information, wherein the first policy information comprises at least one of an access control rule of a network slice, a service processing parameter of the network slice or a charging key value corresponding to the network slice; the policy decision function network element sends the first policy information to a policy execution function network element, where the first policy information is used for the policy execution function network element to execute processing.

In this embodiment of the present application, the policy decision function network element may determine first policy information of the network slice, and indicate the first policy information to the policy execution function network element, so that the policy execution function network element may execute corresponding processing according to the first policy information, so as to improve flexibility of managing a service accessing the network slice. The first policy information may include at least one of an access control rule of the network slice, a service processing parameter, or a charging key value corresponding to the network slice. For example, in a scenario where multiple nsadcfs exist and each NSACF controls a part of an area, each NSACF may obtain first policy information from a PCF, and each NSACF performs corresponding processing in the area controlled by each NSACF according to the received first policy information, instead of performing the same processing on a service accessing the whole network slice according to the same control policy, so that flexibility can be improved.

For example, if the policy enforcement function network element includes an AMF, an SMF, or an NSACF, the first policy information may include an access control rule of the network slice, and if the policy enforcement function network element includes an SMF, the first policy information may include an access control rule of the network slice, a traffic processing parameter of the network slice, or a charging key corresponding to the network slice. Wherein the access control rule may be used to indicate whether a UE within a service area of a policy enforcement function network element is allowed to register to the network slice, or to indicate whether a session is allowed to be established through the network slice within the service area of the policy enforcement function network element, or to indicate whether the UE is allowed to register to the network slice with overrun within the service area of the network slice or a certain NSACF of the network slice, or to indicate whether the session of the network slice is allowed to be established with overrun within the service area of the network slice or a certain NSACF of the network slice.

In one possible design, the policy decision function network element may receive a first request, where the first request is for requesting the first policy information, or the first request is for requesting establishment of a connection, where the connection is for carrying the first policy information. The policy decision function network element may send the first policy information in response to the first request.

In one possible design, the policy decision function network element may determine the first policy information according to policy configuration information from a network slice policy configuration function network element. The network slice policy configuration function network element may include a Unified Data Repository (UDR) or an Application Function (AF). By adopting the design, the flexibility in determining the first strategy information can be improved, so that more means are provided for influencing the decision of the first strategy information according to the business requirement.

In one possible design, the policy decision function network element may determine the first policy information based on at least one of the first information and second information from the policy enforcement function network element. Wherein the first information is used for indicating that the first condition is satisfied. Wherein the first condition comprises: the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is reduced to a first threshold value; or, the number of terminal devices located in the service area of the policy enforcement function network element and registered with the network slice increases to the second threshold. The second information may be used to indicate the number of terminal devices located within the service area of the policy enforcement function network element and registered with the network slice. By adopting the design, the flexibility of the first strategy information determining process and the reasonability of access management of the network slice can be improved.

In one possible design, the policy decision function network element may determine the first policy information based on at least one of the first information and third information from the policy enforcement function network element. Wherein the first information is used for indicating that the first condition is satisfied. Wherein the first condition comprises: the number of sessions which are located in the service area of the policy enforcement function network element and are established through the network slice is reduced to a third threshold value; or, the number of sessions established through the network slice and located within the service area of the policy enforcement function network element increases to a fourth threshold. The third information is used to indicate the number of sessions established through the network slice and located within the service area of the policy enforcement function network element. With this design, the flexibility of the first policy information determination process and the rationality of access management to the network slice can be improved.

In one possible design, the policy decision function network element may obtain quantity information and determine the first policy information according to the quantity information. Wherein the number information is used for indicating the number of terminal devices which are located in the service area of each of the one or more NSACFs and register the network slice, or is used for indicating the number of sessions which are located in the service area of each NSACF and are established through the network slice. By adopting the design, the first strategy information can be determined according to the quantity information of the NSACFs aiming at different NSACFs, the service areas of the different NSACFs can correspond to different first strategy information, and the flexibility of the first strategy information determination process and the rationality of access management to network slices are improved.

In one possible design, the policy decision function network element may determine a first number based on the number information and determine the first policy information based on the first number. The first number is the number of all terminal devices registered to the network slice, or the first number is the number of all sessions established through the network slice. By adopting the design, the first strategy information corresponding to the network slice can be determined according to the number of the registered terminal devices or the number of sessions of the whole network slice, and the configuration efficiency of the strategy information of the network slice is improved.

In one possible design, in a case that the first number indicates that the number of all sessions established through the network slice exceeds (or is not lower than) a fifth threshold, and is located within a service area of the policy enforcement function network element and the number of all sessions established through the network slice is lower than (or does not exceed) a sixth threshold, the first policy information includes a session establishment quota that reserves the network slice for the session to be established. With this design, when the number of all sessions established through the network slice is large and the number of sessions established through the network slice in a service area of a certain NSACF is small, early Admission Control (EAC) is performed to prevent the network slice from establishing sessions beyond the limit, thereby improving communication reliability.

In one possible design, where the first number indicates that the number of all sessions established through the network slice is below (or does not exceed) a seventh threshold, the first policy information includes a number of sessions allowed to be located within a service area of the policy enforcement function network element and established through the network slice that exceeds a first session number limit. By adopting the design, when the number of all the sessions established by the network slice is small, the session of the network slice is allowed to be established in an overrun mode in the service area of the NSACF of the network slice, so that an operator can have means to improve the utilization rate of a service idle area network.

In one possible design, the first number of sessions quota for a first time period is different from the first number of sessions quota for a second time period, and/or the seventh threshold value for the first time period is different from the seventh threshold value for the second time period. With this design, the session number quota or the seventh threshold may be set according to the time period to further improve the flexibility of controlling the session establishment process of the network slice.

In one possible design, the first policy information may further include indication information of an eighth threshold, and the difference between the number of sessions established through the network slice and the first session number quota does not exceed the eighth threshold, and the indication information of the eighth threshold is located in a service area of the policy enforcement function network element.

In one possible design, in a case that the first number indicates that the number of all terminal devices registered in the network slice exceeds (or is not lower than) a ninth threshold, and is located in a service area of the policy enforcement function network element and the number of terminal devices registered in the network slice is lower than (or does not exceed) a tenth threshold, the first policy information includes reserving a registration quota for the terminal devices to be registered. By adopting the design, when the number of all the terminal devices for registering the network slice is larger and the number of the terminal devices for registering the network slice in a service area of a certain NSACF is smaller, the EAC is executed, so that the network slice is prevented from exceeding the registration limit of the terminal devices, and the communication reliability is improved.

In one possible design, in a case where the first number indicates that the number of all terminal devices registered for the network slice is below (or does not exceed) an eleventh threshold, the first policy information includes a first number of terminal devices allowed to be located within a service area of the policy enforcement function network element and registered for the network slice exceeding a first terminal device number limit. By adopting the design, when the number of all the terminal devices for registering the network slice is small, the terminal devices are allowed to be registered to the network slice in an overrun way in the service area of the NSACF of the network slice, so that an operator can have means to improve the utilization rate of a service idle area network.

In one possible design, the first terminal device number quota for a third time period is different from the first terminal device number quota for a fourth time period, or the eleventh threshold for the third time period is different from the eleventh threshold for the fourth time period. With this design, the limit of registered terminal devices or the eleventh threshold value can be set according to the time period to further improve the flexibility of controlling the number of terminal devices registered to the network slice.

In one possible design, the first policy information further includes an indication of a twelfth threshold, and a difference between the number of terminal devices that are located in the service area of the policy enforcement function network element and that register the network slice and the first terminal device number quota does not exceed the twelfth threshold. By adopting the design, the communication capacity of the network can be improved, excessive terminal equipment can be prevented from being registered in the network slice, and the communication reliability is improved.

In one possible design, the first policy information includes traffic processing parameters of the network slice, and the policy enforcement function network element includes an SMF; or, the first policy information includes a charging key corresponding to the network slice, and the policy enforcement function network element includes an SMF. By adopting the design, the flexible control of the service accessed to the network slice can be realized.

In one possible design, when the number of terminal devices registered to the network slice is less than the second terminal device number quota, the first policy information includes that the number of terminal devices allowed to register to the network slice exceeds the second terminal device number quota, and the policy enforcement function network element includes an NSACF; or, when the number of sessions established through the network slice is less than the second session number limit, the first policy information includes that the number of sessions of the network slice is allowed to exceed the second session number limit, and the policy enforcement function network element includes the NSACF.

In one possible design, the policy decision function network element includes a PCF.

In a second aspect, the present application provides a communication method, which may be performed by a policy enforcement function network element, or by a system-on-chip in the policy enforcement function network element, where the system-on-chip is capable of implementing a function of the policy enforcement function network element. The method comprises the following steps: the policy enforcement function network element sends a first request to the policy decision function network element, where the first request is used to request policy information of a network slice, or the first request is used to request to establish a connection, and the connection is used to carry the policy information of the network slice. The policy enforcement function network element receives first policy information from the policy decision function network element, where the first policy information includes at least one of an access control rule of the network slice, a service processing parameter of the network slice, or a charging key value corresponding to the network slice. And the strategy execution function network element executes first processing according to the first strategy information. Taking the 5G communication system as an example, the policy decision function network element is, for example, a policy control function network element.

In one possible design, the policy enforcement function network element may send the first request to the policy decision function network element when the policy enforcement function network element configures the network slice. Alternatively, in case it is determined that the access control of the network slice has been set, for example, when the policy enforcement function network element turns on the access control function switch of the network slice, the policy enforcement function network element may send the first request to the policy decision function network element. Setting the access control of the network slice means that the network slice needs to execute the access control. By adopting the design, the policy execution function network element can send the first request under the condition of configuring the network slice or determining that the network has set the access control of the network slice, so that the acquisition efficiency of the first policy information is improved. In addition, when the precondition for sending the first request is not satisfied, the first request does not need to be sent, so that the transmission overhead is reduced.

In a possible design, if the policy enforcement function network element is an SMF, the policy enforcement function network element may receive a session establishment request from the terminal device before sending the first request, where the session establishment request carries an identifier of the network slice, and when the first policy information includes a service processing parameter of the network slice, the policy enforcement function network element may set the service processing parameter of the session of the terminal device as the service processing parameter of the network slice. When the first policy information includes the charging key corresponding to the network slice, the policy enforcement function network element sets the charging key of the session of the terminal device as the charging key corresponding to the network slice. By adopting the design, if the policy enforcement function network element is the SMF, the SMF can set the session attribute according to the service processing parameter and/or the charging key value of the network slice, and further realize the flexible management of the session established by the network slice.

In one possible design, if the policy enforcement function network element includes an NSACF, and the first policy information includes an access control rule of the network slice, where the access control rule includes an access control rule that allows the number of terminal devices that are located in the service area of the policy enforcement function network element and registered to the network slice to exceed a first terminal device number limit, the policy enforcement function network element may store information of terminal devices to be registered or already registered to the network slice when the number of terminal devices that are located in the service area of the policy enforcement function network element and registered to the network slice is greater than or equal to the first terminal device number limit, and/or accept a first quota reservation application for requesting reservation of a registration quota of the network slice for the terminal devices to be registered to the network slice. In this application, receiving the first quota reservation application may be replaced by sending a response message for instructing to receive the first quota reservation application. The information of the terminal devices to be registered or registered to the network slice is stored to mark the terminal devices as registered terminal devices, so that the number of the terminal devices registered to the network slice is increased by a corresponding value. By adopting the design, when the NSACF allows the UE in the service area to be over-registered, and when the communication requirements of large-scale activities and the like exceed the number of ordinary users, more terminal devices in the service area can be registered to the network slice, and the communication capacity of the network slice is improved according to the service requirements.

In a possible design, the first policy information may further include indication information of a first threshold, and the policy enforcement function network element determines that a difference between the number of terminal devices located in a service area of the policy enforcement function network element and registered to the network slice and the first terminal device number quota does not exceed the first threshold, and accepts the first quota reservation application. With this design, the first policy information may further indicate an overrun proportion or an overrun number allowing the UE in the service area to overrun registration, so as to avoid the UE in the service area from being unlimitedly registered to the network slice to overload, thereby improving communication reliability.

In one possible design, if the first policy information includes an access control rule of the network slice, the access control rule includes an NSACF that is located within a service area of the policy enforcement function network element and a number of sessions established through the network slice exceeds a first session number quota, and the policy enforcement function network element includes an NSACF, the policy enforcement function network element may store information of sessions to be established or established through the network slice and/or accept a second quota reservation application for requesting establishment of a quota for sessions to be established through the network slice when the number of sessions established through the network slice is greater than or equal to the first session number quota. In this application, receiving the second quota reservation application may be replaced by sending a response message for instructing to receive the second quota reservation application. Wherein the information of the sessions to be established or established through the network slice is stored in order to mark the sessions as established sessions so as to reasonably calculate the number of the sessions established through the network slice in the service area. By adopting the design, more sessions can be established in the service area through the network slice at the moment of meeting a major event or a communication peak, and the communication capacity of the network slice is improved according to the service requirement.

In a possible design, the first policy information may further include indication information of a second threshold, and the policy enforcement function network element determines that a difference between the number of sessions established through the network slice and the first session number quota, which are located in a service area of the policy enforcement function network element, does not exceed the second threshold, and accepts the second quota reservation application. With this design, the first policy information may further indicate an overrun proportion or an overrun number of sessions allowed to be established through the network slice in the service area, so as to avoid the network slice from being overloaded due to unlimited establishment of sessions of the network slice in the service area, thereby improving communication reliability.

In one possible design, the policy enforcement function network element includes an NSACF, and when a first condition is satisfied, the policy enforcement function network element may further send first information to the policy decision function network element, where the first information is used to indicate that the first condition is satisfied. Wherein the first condition comprises: the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is reduced to a third threshold value; or, the number of terminal devices which are located in the service area of the policy enforcement function network element and register the network slice increases to a fourth threshold; or, the number of sessions located in the service area of the policy enforcement function network element and established through the network slice is reduced to a fifth threshold; or, the number of sessions established through the network slice and located within the service area of the policy enforcement function network element increases to a sixth threshold. With the above design, the first information may be used to indicate that the first condition is satisfied, so that the policy decision function network element may determine, according to the first information, the number of terminal devices that register a network slice in the service area of the NSACF or the number of sessions established through the network slice in the service area of the NSACF, thereby improving flexibility of number indication.

In a possible design, if the policy enforcement function network element includes an NSACF, the policy enforcement function network element may further send second information to the policy decision function network element when a second condition is satisfied, where the second information is used to indicate the number of terminal devices that are located in the service area of the policy enforcement function network element and that register the network slice. The second condition may include: a sending time condition of the second information, and/or receiving request information of the second information from the policy decision function network element. By adopting the design, the second information can be used for indicating the number of the terminal devices registered with the network slice in the service area of the NSACF, and the flexibility of indicating the number of the UE registered with the network slice in the service area can be improved.

In one possible design, if the policy enforcement function network element includes an NSACF, the policy enforcement function network element may further send, when a third condition is satisfied, third information to the policy decision function network element, the third information indicating a number of sessions established through the network slice and located within a service area of the policy enforcement function network element. Wherein the third condition comprises: a sending time condition of the third information, and/or receiving a request message of the third information from the policy decision function network element. With the above design, the third information may be used to indicate the number of sessions established through the network slice in the service area of the NSACF, and flexibility in indicating the number of sessions of the network slice in the service area may be improved.

In a third aspect, a communications apparatus is provided. The communication device may be the policy decision function network element described in the first aspect, or an electronic device (e.g., a chip system) configured in the policy decision function network element, or a larger device including the policy decision function network element. The policy decision function network element comprises corresponding means (means) or modules for performing the above method. The policy decision function network element is, for example, an access and mobility management function network element, a session management function network element, or a network slice access control function network element. For example, the communication device includes a processing module (sometimes also referred to as a processing unit) and a communication module (sometimes also referred to as a transceiver module). The communication module can implement a transmission function and a reception function, and may be referred to as a transmission unit (also sometimes referred to as a transmission module) when the communication module implements the transmission function, and may be referred to as a reception unit (also sometimes referred to as a reception module) when the communication module implements the reception function. The sending unit and the receiving unit can be the same functional module, the functional module is called as a communication module, and the functional module can realize the sending function and the receiving function; alternatively, the transmitting unit and the receiving unit may be different functional modules, and the communication module is a general term for these functional modules.

For example, in performing the method of the first aspect, the processing module may be configured to determine that the first policy information includes at least one of an access control rule of a network slice, a traffic processing parameter of the network slice, or a charging key corresponding to the network slice. The communication module may be configured to send the first policy information to a policy enforcement function network element.

In one possible design, the communication module may be further configured to receive a first request, where the first request is for requesting the first policy information, or the first request is for requesting establishment of a connection, where the connection is for carrying the first policy information. The processing module may determine the first policy information in response to the first request.

In one possible design, the communication module may be further configured to receive policy configuration information from a network slice policy configuration function network element, and the processing module may be configured to determine the first policy information according to the policy configuration information.

In one possible design, the processing module may be further operable to determine the first policy information based on at least one of the first information and the second information. Wherein the first information is used for indicating that the first condition is satisfied. Wherein the first condition comprises: the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is reduced to a first threshold value; or, the number of terminal devices located in the service area of the policy enforcement function network element and registered with the network slice increases to the second threshold. The second information may be used to indicate the number of terminal devices located within the service area of the policy enforcement function network element and registered with the network slice.

In one possible design, the processing module may be further configured to determine the first policy information based on at least one of the first information and the third information. Wherein the first information is used for indicating that the first condition is satisfied. Wherein the first condition comprises: the number of sessions which are located in the service area of the policy enforcement function network element and are established through the network slice is reduced to a third threshold value; alternatively, the number of sessions established through the network slice and located within the service area of the policy enforcement function network element increases to a fourth threshold. The third information is used to indicate the number of sessions established through the network slice and located within the service area of the policy enforcement function network element.

In one possible design, the processing module may be further configured to obtain quantity information and determine the first policy information according to the quantity information. The quantitative information can be found in the description of the first aspect.

In one possible design, the processing module may be further configured to determine a first number according to the number information, and determine the first policy information according to the first number, where the first number is the number of all terminal devices registered in the network slice, or the first number is the number of all sessions established through the network slice.

In one possible design, in a case that the first number indicates that the number of all sessions established through the network slice exceeds (or is not lower than) a fifth threshold, and is located within a service area of the policy enforcement function network element and the number of all sessions established through the network slice is lower than (or does not exceed) a sixth threshold, the first policy information includes a session establishment quota that reserves the network slice for the session to be established.

In one possible design, where the first number indicates that the number of all sessions established through the network slice is below (or does not exceed) a seventh threshold, the first policy information includes a number of sessions allowed to be located within a service area of the policy enforcement function network element and established through the network slice that exceeds a first session number quota.

In one possible design, the first number of sessions quota for a first time period is different from the first number of sessions quota for a second time period, and/or the seventh threshold value for the first time period is different from the seventh threshold value for the second time period.

In one possible design, in a case that the first number indicates that the number of all terminal devices registered in the network slice exceeds (or is not lower than) a ninth threshold, and is located in a service area of the policy enforcement function network element and the number of terminal devices registered in the network slice is lower than (or does not exceed) a tenth threshold, the first policy information includes reserving a registration quota for the terminal devices to be registered.

In one possible design, in a case where the first number indicates that the number of all terminal devices registered for the network slice is below (or does not exceed) an eleventh threshold, the first policy information includes a first number of terminal devices allowed to be located within a service area of the policy enforcement function network element and registered for the network slice exceeding a first terminal device number limit.

In a possible design, the first terminal device quantity quota for a third time period is different from the first terminal device quantity quota for a fourth time period, or the eleventh threshold value for the third time period is different from the eleventh threshold value for the fourth time period.

In a possible design, the first policy information further includes indication information of a twelfth threshold, and a difference between the number of terminal devices that are located in the service area of the policy enforcement function network element and that register the network slice and the first terminal device number quota does not exceed the twelfth threshold.

In one possible design, the first policy information includes traffic processing parameters of the network slice, and the policy enforcement function network element includes an SMF; or, the first policy information includes a charging key corresponding to the network slice, and the policy enforcement function network element includes an SMF.

In one possible design, the first policy information includes a number of terminal devices allowed to register to the network slice exceeding a second terminal device number quota, the policy enforcement function network element includes an NSACF; alternatively, the first policy information comprises a number of sessions allowed for the network slice to exceed a second session number limit, and the policy enforcement function network element comprises an NSACF.

Optionally, the communication device may further include: a processor, coupled to the memory, for executing the instructions in the memory to implement the method performed by the policy decision function network element in the above-mentioned first aspect. Optionally, the communication device further comprises other components, such as an antenna, an input-output module, an interface, etc. These components may be hardware, software, or a combination of software and hardware.

The technical terms and technical effects related to the above third aspect can be referred to the description of the above first aspect, and are not described herein again.

In a fourth aspect, a communication device is provided. The communication device may be the policy enforcement function network element according to any one of the second aspect, or an electronic device (e.g., a system on chip) configured in the policy enforcement function network element, or a larger device including the policy enforcement function network element. The policy enforcement function network element comprises corresponding means (means) or modules for performing the above method. The policy execution function network element is, for example, an access and mobility management function network element, a session management function network element, or a network slice access control function network element. For example, the communication device includes a processing module (sometimes also referred to as a processing unit) and a communication module (sometimes also referred to as a transceiver module). The communication module is capable of implementing a transmitting function and a receiving function, and may be referred to as a transmitting unit (also sometimes referred to as a transmitting module) when the communication module implements the transmitting function, and may be referred to as a receiving unit (also sometimes referred to as a receiving module) when the communication module implements the receiving function. The sending unit and the receiving unit can be the same functional module, the functional module is called as a communication module, and the functional module can realize the sending function and the receiving function; alternatively, the transmitting unit and the receiving unit may be different functional modules, and the communication module is a general term for these functional modules.

For example, in performing the method of the second aspect, the communication module may be configured to send a first request to a policy decision function network element. The communication module may be further configured to receive first policy information from the policy decision function network element. The processing module may be configured to perform a first process based on the first policy information.

In one possible example, the communication module may be configured to send the first request to the policy decision function network element when the policy enforcement function network element configures the network slice; alternatively, the communication module may be configured to send the first request to the policy decision function network element in case it is determined that the access control for the network slice has been set.

In a possible example, before sending the first request, the communication module may be further configured to receive a session establishment request from the terminal device, where the session establishment request carries an identifier of the network slice. The first policy information includes a service processing parameter of the network slice, and the processing module may be configured to set the service processing parameter of the session of the terminal device as the service processing parameter of the network slice. And/or, if the first policy information includes a charging key of the network slice, the processing module may be configured to set the charging key of the session of the terminal device as the charging key corresponding to the network slice.

In one possible example, if the policy enforcement function network element comprises an NSACF and the first policy information comprises an access control rule for the network slice, the access control rule comprising an allowance that the number of terminal devices located within the service area of the policy enforcement function network element and registered to the network slice exceeds a first terminal device number limit, the processing module may be configured to store information of terminal devices to be registered or already registered to the network slice when the number of terminal devices located within the service area of the policy enforcement function network element and registered to the network slice is greater than or equal to the first terminal device number limit, and/or to accept a first quota reservation application for requesting a reservation of a registration quota for the network slice for the terminal devices to be registered to the network slice, or the communication module may be configured to send a response message indicating receipt of the first quota reservation application.

In a possible example, the first policy information may further include indication information of a first threshold, the processing module may be further configured to determine that a difference between the number of terminal devices located within the service area of the policy enforcement function network element and registered to the network slice and the first terminal device number quota does not exceed the first threshold, and thereafter, the processing module may accept the first quota reservation application, or the communication module may be configured to send a response message indicating reception of the first quota reservation application.

In one possible example, if the first policy information includes an access control rule of the network slice, the access control rule includes a number of sessions that are located within a service area of the policy enforcement function network element and that are established through the network slice exceeds a first number of sessions limit, and the policy enforcement function network element includes an NSACF, the processing module may store information of sessions to be established or established through the network slice when the number of sessions that are located within the service area of the policy enforcement function network element and that are established through the network slice is greater than or equal to the first number of sessions limit, and/or accept a second quota reservation application for requesting to establish a quota for the session to be established through the network slice, or the communication module may be configured to send a response message indicating receipt of the second quota reservation application.

In one possible example, the first policy information may further include an indication of a second threshold, the processing module may be further configured to determine that a number of sessions established through the network slice within a service area of the policy enforcement function network element does not differ from the first quota of number of sessions by more than the second threshold, and thereafter the processing module may accept the second quota reservation application, or the communication module may be configured to send a response message indicating reception of the second quota reservation application.

In one possible design, the policy enforcement function network element includes an NSACF, and when the first condition is satisfied, the communication module may further send first information to the policy decision function network element, the first information indicating that the first condition is satisfied. Wherein the first information is used for indicating that the first condition is satisfied. Wherein the first condition comprises: the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is reduced to a third threshold value; or, the number of terminal devices which are located in the service area of the policy enforcement function network element and register the network slice increases to a fourth threshold; or, the number of sessions located in the service area of the policy enforcement function network element and established through the network slice is reduced to a fifth threshold; or, the number of sessions established through the network slice and located within the service area of the policy enforcement function network element increases to a sixth threshold.

In one possible design, the policy enforcement function network element includes an NSACF, and the communication module may further send a second message to the policy decision function network element when a second condition is satisfied. The second information is used for indicating the number of terminal devices which are located in the service area of the policy enforcement function network element and register the network slice. The second condition may include: a sending time condition of the second information, and/or receiving request information of the second information from the policy decision function network element.

In one possible design, if the policy enforcement function network element includes an NSACF, the communication module may further send, when a third condition is satisfied, third information to the policy decision function network element, the third information indicating a number of sessions that are located within a service area of the policy enforcement function network element and that are established through the network slice. Wherein the third condition comprises: a sending time condition of the third information, and/or receiving a request message of the third information from the policy decision function network element.

The technical terms and technical effects related to the above fourth aspect can be referred to the description of the above second aspect, and are not described herein again.

Optionally, the communication device includes: a processor, coupled to the memory, for executing the instructions in the memory to implement the method performed by the policy enforcement function network element in the second aspect. Optionally, the communication device further comprises other components, such as an antenna, an input-output module, an interface, etc. These components may be hardware, software, or a combination of software and hardware.

In a fifth aspect, a communication system is provided, which comprises a policy decision function network element for performing the method of the first aspect and a policy enforcement function network element for performing the method of the second aspect. Taking the 5G communication system as an example, the policy enforcement function network element may be AMF, SMF or NSACF, and the policy decision function network element may be PCF.

A sixth aspect provides a computer readable storage medium for storing a computer program or instructions which, when executed, cause the method performed by the policy performing function network element or the policy decision function network element in the above aspects to be implemented.

In a seventh aspect, there is provided a computer program product comprising instructions which, when run on a computer, cause the method performed by the policy enforcement function network element or the policy decision function network element in the above aspects to be implemented.

The technical terms and technical effects related to the above second to seventh aspects can be referred to the description of the above first aspect, and are not described herein again.

Drawings

Fig. 1 is a schematic architecture diagram of a wireless communication system provided in the present application;

fig. 2A is a schematic flow chart of a network slice access control method;

fig. 2B is a flowchart illustrating another network slice access control method;

fig. 3 is a schematic flowchart of a communication method provided in the present application;

fig. 4 is a schematic flow chart of another communication method provided in the present application;

fig. 5 is a schematic flow chart of another communication method provided in the present application;

fig. 6 is a schematic flow chart of another communication method provided in the present application;

fig. 7 is a flow chart illustrating another communication method provided herein;

fig. 8 is a schematic structural diagram of a communication device provided in the present application;

fig. 9 is a schematic structural diagram of another communication device provided in the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

Hereinafter, some terms in the embodiments of the present application are explained to facilitate understanding by those skilled in the art.

In the embodiment of the present application, the terminal device is a device having a wireless transceiving function, and may be a fixed device, a mobile device, a handheld device, a wearable device, an in-vehicle device, or a wireless apparatus (e.g., a communication module or a chip system, etc.) embedded in the above device. The terminal device is used for connecting people, objects, machines and the like, and can be widely used in various scenes, such as but not limited to the following scenes: cellular communication, device-to-device communication (D2D), vehicle-to-all (V2X), machine-to-machine/machine-type communication (M2M/MTC), internet of things (IoT), virtual Reality (VR), augmented Reality (AR), industrial control (industrial control), unmanned driving (self driving), remote medical (remote medical), smart grid (smart grid), smart furniture, smart office, smart wear, smart traffic, smart city (smart city), unmanned aerial vehicle, robot, etc. scenarios. The terminal device may sometimes be referred to as a User Equipment (UE), a terminal, an access station, a UE station, a remote station, a wireless communication device, or a user equipment, and for convenience of description, the terminal device is described in this embodiment by taking the UE as an example.

The network device in the embodiment of the present application includes, for example, an access network device (or referred to as an access network element), and/or a core network device (or referred to as a core network element).

The access network equipment is equipment with a wireless transceiving function and is used for communicating with the terminal equipment. The access network device includes, but is not limited to, a base station in the communication system, a transmission and reception point (t (R) ANsmission reception point, TRP), a base station of a subsequent evolution of 3GPP, an access node, a wireless relay node, or a wireless backhaul node in a wireless fidelity (WiFi) system. The base station may be: macro base stations, micro base stations, pico base stations, small stations, relay stations, etc. Multiple base stations may support the same access technology network as mentioned above, or may support different access technologies networks as mentioned above. A base station may include one or more co-sited or non-co-sited transmission reception points. The network device may also be a wireless controller, a Centralized Unit (CU), and/or a Distributed Unit (DU) in a cloud radio access network (C (R) AN) scenario. The network device may also be a server, a wearable device, or a vehicle mounted device, etc. For example, the network device in vehicle to everything (V2X) technology may be a Road Side Unit (RSU). The following description will take the access network device as a base station as an example. The multiple network devices in the communication system may be base stations of the same type or base stations of different types. The base station may communicate with the terminal device, and may also communicate with the terminal device through the relay station. A terminal device may communicate with multiple base stations in different access technologies.

The core network equipment is used for realizing at least one of the functions of mobile management, data processing, session management, policy, charging and the like. The names of devices for implementing the core network function in systems with different access technologies may be different, and this is not limited in this embodiment of the present application. Taking a 5G system as an example, the core network device includes: AMF, SMF, or User Plane Function (UPF), etc., NSACF, and PCF.

In the embodiment of the present application, the apparatus for implementing the function of the network device may be a network device, or may be an apparatus capable of supporting the network device to implement the function, for example, a system on chip, and the apparatus may be installed in the network device. In the technical solution provided in the embodiment of the present application, a device for implementing a function of a network device is taken as an example, and the technical solution provided in the embodiment of the present application is described.

In this application, the number of nouns means "singular nouns or plural nouns" or "one or more" unless otherwise specified. "at least one" means one or more, "a plurality" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a alone, A and B together, and B alone, wherein A and B may be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. For example, A/B, represents: a or B. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, represents: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b and c can be single or multiple.

It should be noted that the policy control function network element, the access and mobility management function network element, the session management function network element, the user plane function network element, the unified data repository network element, the network slice access control function network element, and the like according to the embodiments of the present application are only names, and the names do not limit the device itself. Taking the 5G system as an example, in the present application, the policy control function network element is, for example, a PCF, the access and mobility management function network element is, for example, an AMF, the session management function network element is, for example, an SMF, the network slice access control function network element is, for example, an NSACF, the user plane function network element is, for example, an UPF, and the unified data repository network element is, for example, a Unified Data Repository (UDR). In a non-5G system, for example, in a future other communication system, a policy control function network element, a session management function network element, a user plane function network element, or a unified data repository network element may also correspond to other network elements, which is not specifically limited in this embodiment of the present application.

The 5G communication system architecture is divided into an access network and a core network. Access networks are used to implement radio access related functions, including third generation partnership project (3 GPP) access networks and non- (non) -3GPP access networks. The core network is connected with the access network and is used for realizing functions related to user control management.

Please refer to fig. 1, which is a schematic diagram of a network architecture applied in the embodiment of the present application, for example, a service architecture of a 5G network, and the network architecture is a non-roaming network architecture. The 5G network includes (R) AN equipment, AN UPF, AN AMF, AN SMF, AN authentication server Function (AUSF), a Network Slice Selection Function (NSSF), a network open Function (NEF), a network Function storage Function (NRF), a Policy Control Function (PCF), a Unified Data Management (UDM), a UDR, AN Application Function (AF), or a charging Function (CHF), and the like. It should be noted that fig. 1 only shows some examples of network elements or entities in the 5G network by way of example, and the 5G network may further include network data analysis functions (NWDAFs) and other network elements or entities not shown in fig. 1, which is not specifically limited in this embodiment of the present application.

As shown in fig. 1, the UE accesses the 5G network through (R) AN equipment, and communicates with the AMF through AN N1 interface (N1 for short); (R) the AN device communicates with the AMF over AN N2 interface (N2 for short); (R) the AN device communicates with the UPF through AN N3 interface (N3 for short); the SMF communicates with the UPF via an N4 interface (N4 for short), and the UPF accesses a Data Network (DN) via an N6 interface (N6 for short). Control plane functions such as AUSF, AMF, SMF, NSSF, NEF, NRF, PCF, UDM, UDR, CHF, or AF shown in fig. 1 interact using a service interface. For example, the serving interface provided by the AUSF is Nausf; the serving interface provided by the AMF is Namf; the SMF provides a service interface for the outside as Nsmf; the external service interface provided by the NSSF is Nnssf; the serving interface provided by the NEF is Nnef; the NRF provides a service interface for the outside as Nnrf; the PCF provides a service interface to the outside as Npcf; a serving interface externally provided by the UDM is Nudm; the external serving interface provided by the UDR is Nudr; the serving interface externally provided by the CHF is Nchf; the service interface provided by the AF to the outside is Naf. The description of related functions and interfaces can refer to the 5G system architecture (5G system architecture) diagram in the 23501 standard, which is not repeated herein.

The following describes a manner in which the UE registers to the network slice, taking the 5G scenario shown in fig. 1 as an example.

Currently, when a UE requests access to a network slice, an EAC mechanism may be employed to control registration of the UE to the network slice and/or to control session establishment for the network slice. As shown in fig. 2A, when the number of terminal devices registered in the network slice is far less than the maximum number of registered terminal devices in the network slice, the NSACF turns off the EAC mechanism, so that the EAC mechanism is in a deactivated state (or deactivated EAC), and the process of registering the UE in the network slice includes the following steps:

step A0: and when the NSACF judges that the number of the terminal equipment registered to a certain network slice is far smaller than the maximum registered terminal equipment number of the network slice, the NSACF sends a message to the AMF to indicate that the EAC mechanism associated with the network slice is set to be in a deactivation state.

Step A1: the AMF receives a registration request from the UE, wherein the registration request can carry the identification of the network slice which the UE requests to access. For example, the network slice is identified as Network Slice Selection Assistance Information (NSSAI), where NSSAI includes one or more S-NSSAIs. The AMF may determine, according to the configuration, that the registration mechanism of the network slice corresponding to the S-NSSAI is controlled by the EAC mechanism, and may further query whether the EAC mechanism is in an active state.

Step A2: the AMF may process the registration request of the UE if it is determined that the EAC mechanism associated with the network slice is in a deactivated state. For example, the AMF may interact with network functions such as UDM and NSSF to complete registration request processing of the UE, and send NSSAI (Allowed NSSAI) of a network slice to which the UE is Allowed to access to the UE, where the Allowed NSSAI includes some or all of S-NSSAIs in the NSSAI to which the UE requests to access, so that the UE successfully registers to the network slice corresponding to the Allowed NSSAI. The AMF then determines the number of currently registered terminal devices that need to update the network slice with the NSACF.

Step A3: since the UE successfully registers to access the network slice, the AMF sends a message to the NSACF to update the number of currently registered terminal devices of the network slice, that is, to instruct the NSACF to increase the number of terminal devices registered to the network slice by 1.

Step A4: the NSACF increases the number of terminal devices registered to the network slice by 1 according to a message from the AMF.

It should be noted that, after the UE registers in the network slice, if the UE logs off from the network slice at a later stage (including logging off from the entire network, or after the UE re-registers in the network, the Allowed nsai does not include the above two cases of S-nsai), after the logging off is completed, the corresponding AMF sends a message to the NSACF to update the number of currently registered terminal devices of the network slice, that is, the number of terminal devices registered in the network slice is reduced by 1 by the NSACF.

For another example, when the number of terminal devices registered in the network slice exceeds a certain threshold or approaches the maximum number of registered terminal devices in the network slice, the NSACF starts the EAC mechanism, so that the EAC mechanism is in an active state (or called active EAC). The process of UE registration to network slice at this time includes the following steps as shown in fig. 2B:

step B0: when the NSACF judges that the number of the terminal devices registered in a certain network slice is close to the maximum registered terminal device number of the network slice (or exceeds a certain threshold), the NSACF sends a message to the AMF to indicate that the EAC mechanism associated with the network slice is set to be in an activated state.

Step B1: the AMF receives a registration request from the UE, wherein the registration request can carry the identification of the network slice to which the UE requests to access. For example, the network slice is identified as NSSAI, where NSSAI includes one or more S-NSSAIs. The AMF may determine, according to the configuration, that the registration mechanism of the network slice corresponding to the S-NSSAI is controlled by the EAC mechanism, and may further query whether the EAC mechanism is in an active state.

And step B2: in the case that the AMF determines that the EAC mechanism associated with the network slice is in an active state, before processing the registration request of the UE, the AMF needs to send a request message, which may be referred to as a first quota reservation application, to the NSACF to check and update the number of terminal devices registered to the network slice. Based on the message, the AMF may request the NSACF to check whether the number of terminal devices currently registered to the network slice has reached the maximum number of registered terminal devices of the network slice, and if not, the message may also be used to request the NSACF to increase the number of terminal devices registered to the network slice by 1 in advance, thereby reserving a registration quota for the UE to register to the network slice.

Accordingly, the NSACF returns a response message based on the message to the AMF to indicate the checking and updating result of the number of terminal devices.

And step B3: if the number of the terminal devices currently registered in the network slice does not reach the maximum number of the registered terminal devices of the network slice, the NSACF increases the number of the terminal devices registered in the network slice by 1, and sends a response message to the AMF to indicate that the maximum number of the registered terminal devices of the network slice is not reached, and the NSACF reserves a registration quota for the UE to be registered in the network slice.

And step B4: after receiving the response message of the NSACF, if the message indicates that the current terminal equipment number of the network slice does not exceed the maximum terminal equipment number of the slice, the AMF starts to process the registration request of the UE. Otherwise, the AMF refuses to register the UE to the network slice.

And step B5: after the NSACF increases the number of terminal devices registered to the network slice by 1 for the UE, if the UE fails to register to the network slice due to registration failure, the nsai assigned by the network to the UE does not include the S-nsai of the network slice, and the like, the AMF needs to send a message to the NSACF updating the number of terminal devices registered to the network slice for instructing the NSACF to decrease the number of terminal devices registered to the network slice by 1.

B6: the NSACF reduces the number of terminal devices registered to the network slice by 1 according to the indication of the AMF.

By the above method, when the EAC mechanism is in the deactivated state, the AMF only needs to notify the NSACF of the change in the number of currently registered UEs after processing the registration request of the UE. Because the interaction result of the NSACF does not need to be waited, the registration request processing time delay of the UE is greatly shortened, and meanwhile, when the UE fails to be successfully registered to the network slice, the NSACF is not required to be instructed to cancel the pre-increased number of registered terminal devices through an additional message. When the EAC mechanism is in an active state, the AMF processes the registration request of the UE after the NSACF successfully reserves a quota for the registration of the UE, so as to ensure that the number of UEs registered to the network slice does not exceed the quota. Thus, according to fig. 2A and 2b, the amf and NSACF may decide whether to control the number of UEs registered to a network slice according to whether EAC is activated.

It should be understood that, in the above description, the process of processing the registration request of the UE by the AMF is taken as an example, and the SMF and the NSACF may also control the number of PDU sessions (hereinafter, referred to as sessions) accessed to the network slice by activating the EAC or deactivating the EAC, and a specific control manner is similar to the manner in which the AMF and the NSACF control the number of UEs registered to the network slice according to the EAC mechanism, and is not described again.

Taking fig. 2A and fig. 2B as an example, the current AMF only accepts or rejects the request of the UE for accessing the network slice according to the response of the NSACF when the EAC mechanism is activated, the NSACF can only accept or reject the corresponding request according to whether the number of all UEs registering the network slice reaches the threshold or the maximum limit, and cannot flexibly control the processing of the registration request according to the number of terminal devices registering the network slice in the service area of the NSACF where the UE is located. The SMF has the same control process for the session establishment request of the network slice, and lacks flexibility.

The embodiment of the application provides a communication method. The method can be realized by the interaction of a strategy execution function network element and a strategy decision function network element. The policy decision function network element may be a policy control function network element (e.g., PCF). The policy enforcement function network element may be an access and mobility management function network element (e.g., AMF), a session management function network element (e.g., SMF), or a network slice access control function network element (e.g., NSACF).

As shown in fig. 3, the method may include the steps of:

s101: the policy enforcement function network element sends a first request to the policy decision function network element. The first request is used for requesting the policy information of the network slice, or the first request is used for requesting to establish a connection, and the connection is used for carrying the policy information of the network slice.

The policy enforcement function network element may send the first request when the policy enforcement function network element configures the network slice. In this application, configuring a network slice refers to configuring the network slice by a policy enforcement function network element according to configuration information. For example, after the policy enforcement function network element is started, when function configuration is started according to configuration information, where the configuration information includes an S-NSSAI corresponding to the network slice, the first request may be sent.

Alternatively, the policy enforcement function network element may send the first request upon determining that access control for the network slice has been set. The setting of access control of the network slice means turning on a switch for performing access control on the network slice. For example, in case of turning on the switch for access control, the AMF may control the UE to register to the network slice according to the activated or deactivated state of the EAC mechanism. For example, when the policy enforcement function network element determines that the function switch for performing access control on the network slice is turned on when processing a terminal device registration request or a session establishment request of the network slice, the policy enforcement function network element sends a first request.

In addition, if the policy enforcement function network element is the AMF, the policy enforcement function network element may further send the first request after receiving a registration request for registering to the network slice. Wherein the registration request may carry an identification of the network slice, such as S-NSSAI. The registration request may be the first registration request carrying the S-NSSAI. Or, if the policy enforcement function network element is an SMF, the policy enforcement function network element may further send the first request after receiving a request (or called session establishment request) for establishing a session of the network slice, where the request may carry an identifier of the network slice, such as S-NSSAI. The session establishment request may be the first session establishment request carrying the S-NSSAI.

Accordingly, the policy decision function network element receives the first request.

S102: the policy decision function network element determines first policy information.

The first policy information includes at least one of an access control rule of the network slice, a service processing parameter of the network slice, or a charging key value (charging key) corresponding to the network slice.

The following is a detailed description of the content that the first policy information may contain.

(1) Access control rules for a network slice, rules that may be used to determine whether to allow a UE to register with the network slice or to allow a session for the network slice to be established.

In one aspect, the access control rules in the present application may be used to indicate whether to allow an over-limit registration of a UE, or to indicate whether to allow an over-limit establishment of a session.

For example, if the policy enforcement function network element is an NSACF, the access control rule may be used to indicate whether the number of UEs registered to the network slice that are located within the service area of the NSACF is allowed to exceed a maximum terminal device number quota (which may be referred to as a first terminal device number quota) within the service area. It should be understood that the value of the first terminal device number quota may be different for different nsafcs. The first terminal device number quota is for example the maximum number of UEs registered to the network slice within the service area in the usual case. The first terminal equipment count is known to the NSACF. Here, the service area of an NSACF refers to a network range in which all AMFs controlled by a certain NSACF can provide services. For convenience, if the number of UEs registered in the service area of the NSACF to the network slice is allowed to exceed the maximum number of terminal devices in the service area, it may be referred to as UE over-registration allowed in the service area of the NSACF, otherwise, it may be referred to as UE over-registration not allowed in the service area of the NSACF.

The first policy information may further include an indication of the first threshold in case the number of UEs registered to the network slice that are allowed to be located within the service area of the NSACF exceeds the first terminal device number quota. In one possible example, the difference between the number of UEs registered to the network slice located within the service area of the NSACF and the first terminal device number quota does not exceed the first threshold, that is, the first threshold and the first terminal device number quota are used to determine the maximum number of UEs registered to the network slice located within the service area of the NSACF. In the present application, the difference between a and B means a value obtained by subtracting B from a, and the value is greater than 0.

Alternatively, the first threshold may be determined based on the first terminal device number limit, for example, the product of the first terminal device number limit and a proportional value a, where a is a positive number. At this time, the maximum number of UEs registered to the network slice that are allowed to be located within the service area of the NSACF is the product of (a + 1) and the first terminal device number limit. Alternatively, the first threshold may be a positive integer, where the maximum number of UEs registered to the network slice that are allowed to be located within the service area of the NSACF is the sum of the first threshold and the first terminal device number quota. a may be a predefined value, a protocol defined value, a value pre-configured at the NSACF, or may be a PCF-indicated value.

Alternatively, the first policy information may further include indication information of a maximum number of UEs allowed to be located within the service area of the NSACF and registered to the network slice.

Accordingly, an NSACF may allow UEs to register to the network slice if the number of UEs currently located within the service area of the NSACF registering the network slice does not exceed the maximum number. That is, at this time, if the AMF sends a first quota reservation application to the NSACF, the first quota reservation application is used to request the NSACF to reserve a registration quota for the UE registered in the network slice, and the NSACF may accept the first quota reservation application when the number of UEs currently located in the service area of the NSACF and registered in the network slice does not exceed the maximum number.

Similarly, if the policy enforcement function network element is an NSACF, the access control rules may also be used to indicate whether the number of sessions established through the network slice within the service area of the NSACF is allowed to exceed a maximum session number quota within the service area (which quota may be referred to as a first session number quota). The first session quantity quota is, for example, the maximum number of sessions established through the network slice within the service area in the usual case. The service area of an NSACF refers to a network range in which all SMFs controlled by a certain NSACF can provide services. The first session number quota is known to the NSACF. If the S-nsai carried at the session setup is the identity of the network slice and the SMF controlling the session is controlled by the NSACF, then the session is the session of the network slice located within the NSACF service area. For convenience of description, if the number of sessions established through the network slice in the service area of the NSACF is allowed to exceed the maximum session number quota in the service area, the session over-establishment is allowed in the service area of the NSACF, otherwise, the session over-establishment is not allowed in the service area of the NSACF.

The first policy information may further include an indication of a second threshold in the case where the number of established sessions located within the service area of the NSACF over the network slice is allowed to exceed the first session number quota. In one possible example, the difference between the number of sessions established through the network slice located within the service area of the NSACF and the first session number allowance does not exceed a second threshold, i.e., the second threshold and the first session number allowance may be used to determine a maximum number of sessions established through the network slice located within the service area of the NSACF.

Alternatively, the second threshold may be determined according to the first session number quota, for example, a product of the first session number quota and a proportional value b, where b is a positive number, where the maximum number of sessions established through the network slice that are allowed to be located in the service area of the NSACF is a product of (b + 1) and the first session number quota, or may be a positive integer, where the maximum number of sessions established through the network slice that are allowed to be located in the service area of the NSACF is a sum of the second threshold and the first session number quota. b may be a predefined value, a protocol defined value, a value pre-configured at the NSACF, or may be a PCF-indicated value.

Alternatively, the first policy information may further include indication information that allows a maximum number of sessions established through the network slice to be located within the service area of the NSACF.

Accordingly, an NSACF may allow establishment of sessions for a network slice currently located within a service area of the NSACF without exceeding the maximum number of sessions for the network slice. That is to say, at this time, if the AMF sends a second quota reservation application to the NSACF to request the NSACF to establish a quota for the session reservation session of the network slice, the NSACF may accept the application under the condition that the number of sessions of the network slice currently located in the service area of the NSACF does not exceed the maximum number.

On the other hand, in the present application, the access control rule may also be used to indicate that EAC is activated or deactivated within the service area of a certain NSACF of a certain network slice. If the EAC is activated, the AMF in the service area of the NSACF needs to apply for a UE registration quota to the NSACF before processing the registration request of the S-NSSAI carrying the network slice, and similarly, the SMF in the service area of the NSACF needs to apply for a session establishment quota to the NSACF before processing the session establishment request of the S-NSSAI carrying the network slice. If EAC is deactivated, the AMF in the service area of the NSACF can process the registration request for requesting registration to the network slice without applying for UE registration quota, and similarly, the SMF in the service area of the NSACF can process the request for requesting session establishment through the network slice without applying for session establishment quota.

(2) The traffic processing parameters of the network slice include, but are not limited to, qoS parameters of sessions of the network slice, and may be used for the SMF to set corresponding sessions according to the QoS parameters. If the policy enforcement function network element is an SMF, the SMF may set the service processing parameter of the session corresponding to the network slice according to the service processing parameter. The corresponding session means that, after receiving the first policy information including the service processing parameter, if the SMF is currently processing the session establishment request of the network slice or receives the session establishment request of the network slice later, the SMF sets the QoS parameter of the session according to the service processing parameter set to the session, for example, according to the QoS parameter carried by the first policy information. Illustratively, the traffic handling parameters may indicate that the SMF employs default QoS parameters for the session.

(3) The charging key may be used to perform charging for the session for the network slice. Different charging key values correspond to different charging standards in the charging system. If the policy enforcement function network element is an SMF, the SMF may set the charging key value of the session corresponding to the network slice to the charging key value carried by the first policy information, in the same way as the service processing parameter.

It is to be understood that the first policy information may be associated with certain conditions, i.e. the policy enforcement function network element may enforce the first processing according to the first policy information when certain conditions are met. For example, the condition may be a time condition, such as that the first policy information is validated between ten am and twelve am, and that other first policy information is validated between twelve am and two pm, wherein the policy enforcement function network element may perform the first process according to the validated first policy information. For another example, if the policy enforcement function network element receives indication information for indicating the first policy information that is in effect, where the indication information may carry an index of the first policy information that is in effect, the policy enforcement function network element may, after receiving the indication information, perform the first processing according to the first policy information.

Optionally, before S102, if the policy enforcement function network element is an NSACF, the NSACF may further send the first information and/or the second information, or the first information and/or the third information to the policy decision function network element. Accordingly, the policy decision function network element may determine the first policy information from the first information and/or the second information, or determine the first policy information from the first information and/or the third information.

Taking the example where the policy decision function network element is a PCF, the NSACF may send first information to the PCF when the first condition is satisfied, where the first information may be used to indicate that the first condition is satisfied.

In particular, the first condition may include that the number of UEs of the registered network slice located within the service area of the NSACF decreases to a third threshold, and thus, the PCF may determine, from the received first information, that the number of UEs of the registered network slice currently located within the service area of the NSACF is the third threshold. Wherein the third threshold may be less than, equal to, or greater than the first terminal device number limit.

Alternatively, the first condition may include that the number of UEs of the registered network slice located within the service area of the NSACF increases to a fourth threshold, and thus, the PCF may determine, from the received first information, that the number of UEs of the registered network slice currently located within the service area of the NSACF is the fourth threshold. Wherein the fourth threshold may be less than, equal to, or greater than the first terminal device quantity quota. The value of the fourth threshold may be the same as or different from the value of the third threshold.

Alternatively, the first condition may include that the number of sessions established through the network slice located within the service area of the NSACF decreases to a fifth threshold, and thus, the PCF may determine the number of sessions established through the network slice located within the service area of the NSACF to be the fifth threshold according to the received first information. Wherein the fifth threshold may be less than, equal to, or greater than the first session number quota.

Alternatively, the first condition may include that the number of sessions established through the network slice located within the service area of the NSACF increases to a sixth threshold, and thus, the PCF may determine, from the received first information, that the number of sessions established through the network slice located within the service area of the NSACF is the sixth threshold. Wherein the sixth threshold may be less than, equal to, or greater than the first session number limit. The value of the sixth threshold may be the same as or different from the value of the fifth threshold.

Still taking the example where the policy decision function network element is a PCF, the NSACF may also send second information to the PCF when a second condition is satisfied, the second information being usable to indicate a number of UEs of the registered network slice located within a service area of the NSACF. For example, the second condition may include the NSACF determining that a transmission time or event condition of the second information is satisfied. The time condition is, for example, that when the second information is transmitted according to a period, the period is reached from a time interval at which information indicating the number of UEs registered for the network slice located in the service area of the NSACF is last transmitted, or the time condition includes a transmission time of the second information indicated by reaching the preconfiguration or PCF or other network element. The time condition is, for example, that the NSACF receives the request information of the second information from the PCF. Therefore, after receiving the second information, the PCF can know the number of UEs currently located in the service area of the NSACF and registered to the network slice according to the second information.

Like the second information, the third information may be used to indicate the number of sessions established through the network slice located within the service area of the NSACF. Accordingly, the NSACF may transmit the third information when the third condition is satisfied. The third condition may include the NSACF determining that a transmission time or event condition of the second information is satisfied, and the time condition may include request information that the third information is received from the PCF. The third condition may be set in a manner described with reference to the second condition, for example, the third condition includes a time condition, or includes that the NSACF receives a request message for requesting the third information from the PCF. Accordingly, after receiving the third information, the PCF can obtain the number of sessions established through the network slice currently located in the service area of the NSACF according to the second information.

In the following, a manner of determining the first policy information for the policy decision function network element is described by taking the example that the policy decision function network element is a PCF.

In mode 1, the pcf may obtain quantity information and determine the first policy information based on the quantity information.

In one possible implementation, the quantity information may indicate a quantity of UEs located within a service area of one or more nsafs and registered with the network slice, for example, the quantity information may be determined according to the first information or the second information from the one or more nsafs. The PCF may determine its corresponding first policy information for each NSACF, wherein the first policy information determined by the PCF for different nsafcs may be different if the number of UEs registering the network slice within the service area of the different nsafcs indicated by the number information is different.

For example, if the number of UEs registered in a certain network slice in the service area of the first NSACF is smaller than the number of UEs registered in the same network slice in the service area of the second NSACF, the QoS quality of service corresponding to the QoS parameter indicated by the first policy information corresponding to the first NSACF may be higher than the QoS quality of service corresponding to the QoS parameter indicated by the first policy information corresponding to the second NSACF. Alternatively, the charging standard corresponding to the charging key indicated by the first policy information corresponding to the first NSACF may be higher than the charging standard corresponding to the charging key indicated by the first policy information corresponding to the second NSACF.

Further, if the number of UEs registered for a certain network slice within the service area of the first NSACF is smaller than the number of UEs registered for the same network slice within the service area of the second NSACF, the first policy information corresponding to the first NSACF may include an access control rule indicating that the EAC mechanism of the first NSACF is set to a deactivated state, and/or the first policy information corresponding to the second NSACF may include an access control rule indicating that the EAC mechanism of the second NSACF is set to an activated state. Optionally, the number of UEs within the service area of the first NSACF registering for a certain network slice may be less than (or not greater than) the UE number threshold for the EAC mechanism requiring activation of the first NSACF, and/or the number of UEs within the service area of the second NSACF registering for the same network slice may be greater than (or not less than) the UE number threshold for the EAC mechanism requiring activation of the second NSACF.

The UE number threshold for activating the EAC mechanism of the first NSACF is, for example, a product of the first terminal device number allowance allowed to register to the network slice in the first NSACF and a ratio value X, where 0 is smaller than X and smaller than 1, or a set value. Similarly, the UE number threshold for the EAC mechanism that requires activation of the second NSACF may be set with reference. X may be a predefined value, a protocol defined value, a value pre-configured at the first NSACF, or may be a PCF-indicated value.

In another possible implementation, the quantity information may be used to indicate the number of sessions that are located within the service area of the one or more nsafs and that are established through the network slice, for example, the quantity information may be determined based on the first information or the third information from the one or more nsafs. The PCF may determine its corresponding first policy information for each NSACF, wherein the first policy information determined by the PCF for different NSACF may be different if the number of sessions established through the network slice within the service area of the different NSACF indicated by the number information is different.

Taking the example that the service processing parameter indicated by the first policy information is a QoS parameter, if the number of sessions established in the service area of the first NSACF through the network slice is smaller than the number of sessions established in the service area of the second NSACF through the network slice, the QoS quality of service corresponding to the QoS parameter indicated by the first policy information corresponding to the first NSACF may be higher than the QoS quality of service corresponding to the QoS parameter indicated by the first policy information corresponding to the second NSACF, for example, it is limited that a session in the service area of the second NSACF can only adopt a default QoS parameter (e.g., adopt a session aggregation maximum bit rate (session-AMBR)), and cannot use a QoS parameter obtained by SMF from Unified Data Management (UDM) when the network slice signs. Alternatively, the charging standard corresponding to the charging key value indicated by the first policy information corresponding to the first NSACF may be higher than the charging standard corresponding to the charging key value indicated by the first policy information corresponding to the second NSACF.

Further, if the number of sessions established through the network slice within the service area of the first NSACF is smaller than the number of sessions established through the network slice within the service area of the second NSACF, the first policy information corresponding to the first NSACF may include an access control rule for indicating that the EAC mechanism of the first NSACF is set to a deactivated state, and/or the first policy information corresponding to the second NSACF may include an access control rule for indicating that the EAC mechanism of the second NSACF is set to an activated state. Optionally, the number of sessions established over the network slice in the service area of the first NSACF may be less than (or not greater than) the session number threshold for the EAC mechanism requiring activation of the first NSACF, and/or the number of sessions established over the network slice in the service area of the second NSACF may be greater than (or not less than) the session number threshold for the EAC mechanism requiring activation of the second NSACF.

The threshold of the number of sessions of the EAC mechanism that needs to activate the first NSACF is, for example, a product of a first number of sessions quota allowed to be established through the network slice in the first NSACF and a ratio value Y, where 0 is smaller than Y and smaller than 1, or a set value. Y may be a predefined value, a protocol defined value, a value pre-configured at the NSACF, or may be a value indicated by the PCF. Similarly, the threshold for the number of sessions for the EAC mechanism that requires activation of the second NSACF may be set with reference.

Mode 2, the first policy information is determined according to a first number, where the first number is the number of all terminal devices registered in the network slice or the number of all sessions established through the network slice.

The first number may be determined by the PCF according to the number information of all nsacfcs corresponding to the network slice, for example, the PCF may obtain the first number by accumulating the number information of all nsacfcs corresponding to the network slice. This quantity information can be seen in the description of mode 1.

In a possible implementation manner, when the number of sessions indicated by the first number exceeds the seventh threshold, even if the number of sessions established through the network slice in the service area of a certain NSACF is small, for example, does not exceed the eighth threshold, the PCF may carry, in the first policy information corresponding to the NSACF, an access control rule for instructing the NSACF to set the EAC mechanism to the active state. The seventh threshold may be a product of a maximum number of sessions established through the network slice (i.e., a maximum session establishment number) and a ratio value Z, 0 being less than Z being less than 1, or may be a set value. The eighth threshold is, for example, a number of sessions threshold that requires activation of the EAC mechanism of the NSACF. The eighth threshold may be less than the seventh threshold. Z may be a predefined value, a protocol defined value, a value pre-configured at the NSACF, or may be a PCF-indicated value.

In addition, when the number of sessions established through the network slice is less than (or does not exceed) the second session number quota, the PCF may also allow the number of sessions established through the network slice to exceed the second session number quota (which may be referred to as the number of sessions allowed for the network slice exceeding in the following), and at this time, the access control rule carried by the first policy information may be used to indicate that the number of sessions established through the network slice exceeds the second session number quota. For example, in a meeting or emergency situation, the limit set in normal times is temporarily allowed to be exceeded to increase the communication capacity. The second session number limit is, for example, a maximum number of sessions allowed to be established through the network slice under normal circumstances, and the PCF may indicate to the NSACF that the number of sessions allowed to be established through the network slice exceeds the second session number limit for a specified period of time. The NSACF controls the number of sessions of the network slice according to the indication not according to the second session number quota during the validity period, that is, the NSACF allows sessions to be established through the network slice. At this time, the PCF may also indicate (as indicated by the first policy information and/or the access control rule) to the NSACF that the limit on the number of sessions allowed to be established through the network slice is a product of the second limit on the number of sessions and a proportional value U, U being greater than 1, or the limit on the number of sessions allowed to be established through the network slice is a set value greater than the second limit on the number of sessions, or the PCF may indicate to the NSACF the difference of U or the set value and the second limit on the number of sessions. The PCF may also set U or an effective time period of the set value, and the NSACF may control the number of sessions of the network slice according to a product of the second session number quota and U or according to the set value within the effective time period as instructed by the PCF. U may be a predefined value, a protocol defined value, a value pre-configured in the NSACF, or may be a PCF-indicated value.

If the number of sessions indicated by the first number does not exceed the ninth threshold (which may be the same as or different from the seventh threshold, which may be the maximum number of sessions established through the network slice), the PCF may optionally carry, in the first policy information for any of the nsafs for the network slice, an access control rule that allows the number of sessions located within the service area of the nsafs and established through the network slice to exceed the first session number quota corresponding to the nsafs, and/or carry information indicative of a second threshold that may determine the maximum number of sessions allowed to be established through the network slice within the service area, e.g., the difference between the number of sessions established through the network slice located within the service area of an nsaf and the first session number quota does not exceed the second threshold. It should be understood that, within the service area of different nsafcs, if the number of sessions established through the network slice is different, the values of the second thresholds of the different nsafcs may be different. Alternatively, the second threshold value may take the same value for different nsafcs. Optionally, in the above example, a value of the ninth threshold in the first time period is different from a value of the ninth threshold in the second time period, and the first time period and the second time period are different time periods.

In another possible implementation manner, if the number of UEs indicated by the first number exceeds the tenth threshold, even if the number of UEs registering the network slice in the service area of a certain NSACF is small, for example, does not exceed the eleventh threshold, the PCF may carry, in the first policy information corresponding to the NSACF, an access control rule for instructing the NSACF to set the EAC mechanism to the active state. The tenth threshold may be a product of the maximum number of terminal devices registered to the network slice (i.e., the maximum number of registered terminal devices) and P%, 0 being less than P being less than 100, or may be a set value. The eleventh threshold is, for example, a UE number threshold that requires activation of the EAC mechanism of the NSACF. The eleventh threshold may be less than the tenth threshold.

In addition, when the number of terminal devices registered in the network slice is less than (or does not exceed) the second terminal device number limit, the PCF may also allow the number of terminal devices registered in the network slice to exceed the second terminal device number limit (which may be referred to as allowing the number of registered terminal devices in the network slice to exceed the second terminal device number limit, where the access control rule carried by the first policy information may be used to indicate that the number of terminal devices registered in the network slice is allowed to exceed the second terminal device number limit. The second terminal device quantity quota is, for example, a maximum number of terminal devices allowed to register to the network slice under normal circumstances, and the PCF may indicate to the NSACF that the number of terminal devices allowed to register to the network slice exceeds the second terminal device quantity quota for a specified period of time. The NSACF controls the number of registered terminal devices of the network slice according to the indication that the second number of terminal devices is not quota controlled during the valid time period, i.e. the UE is allowed to register to the network slice in the NSACF. At this time, the PCF may also indicate (as indicated by the first policy information and/or the access control rule) to the NSACF that the limit of the number of terminal devices allowed to register to the network slice is a product of the limit of the number of second terminal devices and a proportionality value V, V being greater than 1. Alternatively, the limit of the number of terminal devices registered to the network slice is allowed to be a set value larger than the limit of the number of second terminal devices, or the PCF may indicate V or a difference of the set value and the limit of the number of second terminal devices to the NSACF. The PCF may further set V or an effective time period of the set value, and the NSACF may control the number of terminal devices registered to the network slice according to the product of the second conference terminal device number quota and V or according to the set value within the effective time period according to the instruction of the PCF. V may be a predefined value, a protocol defined value, a value pre-configured in the NSACF, or may be a PCF-indicated value.

On the contrary, if the number of UEs indicated by the first number does not exceed the twelfth threshold, optionally, the PCF may carry, in the first policy information for any NSACF of the network slice, an access control rule that allows the number of terminal devices registered to the network slice within the service area of the NSACF to exceed the first terminal device number quota corresponding to the NSACF, and/or carry indication information of a first threshold, which may be used to determine a maximum number of UEs allowed to be registered to the network slice within the service area, for example, a difference between the number of UEs registered to the network slice within the service area of the NSACF and the first terminal device number quota does not exceed the first threshold. It should be understood that within the service areas of different nsafcs, if the number of terminal devices registered for the network slice is different, the corresponding first threshold values may be different. Alternatively, the first threshold values are the same for different nsafcs.

Optionally, in the above example, a value of the twelfth threshold in the first time period is different from a value of the twelfth threshold in the second time period, and the first time period and the second time period are different time periods.

Optionally, in S102, the policy decision function network element may determine the first policy information according to the policy configuration information from the policy configuration function network element, for example, the policy configuration information may be used to indicate a rule for determining the first policy information as exemplified above. The policy configuration function network element may be a unified data repository network element (e.g., UDR) or an application function network element (e.g., AF).

If the policy configuration function network element is a UDR, the policy configuration information may be configured in the network in advance, for example, the UDR may configure and store the policy configuration information corresponding to each time period, or the policy configuration information corresponding to each condition. If the policy configuration function network element is an AF, the policy configuration information may be policy information for a set or modified network slice, which may be flexibly indicated by the AF, for example, the AF may obtain status information of network slice control (e.g., a current number of UEs registered by the network slice or a current session) from the slice PCF, and optionally, an access control rule currently in use (e.g., whether to allow over-registration of UEs or establishment of sessions, etc.), for manually entering the configuration information to configure or modify the current access control rule through the setting of the configuration information. In addition, the configuration information stored in the UDR may be configured by the AF and stored in the UDR.

S103: and the policy decision function network element sends the first policy information to the policy execution function network element.

The first policy information may correspond to the policy enforcement function network element, e.g., the first policy information is in effect within a service area of the policy enforcement function network element.

Optionally, the first request in S101 may be used to subscribe to policy information of the network slice, where the policy information relates to UE registration and/or session establishment policies of the network slice. The policy decision function network element may send the first policy information to the policy enforcement function network element according to a period or when the policy information of the network slice for the policy enforcement function network element changes.

Accordingly, the policy enforcement function network element receives the first policy information.

S104: and the strategy execution function network element executes the first processing according to the first strategy information.

Illustratively, when the policy enforcement function network element is an NSACF, and the first policy information includes an access control rule that allows the number of UEs located in the service area of the NSACF and registered to the network slice to exceed the first terminal device number limit, the first processing performed by the NSACF may include storing information of the terminal devices to be registered or registered to the network slice, where the terminal devices to be registered or registered are UEs that send registration requests to the AMF. The first processing performed by the NSACF may further include accepting the first quota reservation application in a case that a number of UEs currently located within a service area of the NSACF registering the network slice does not exceed a sum of the first terminal device number quota and a first threshold. The first quota reservation application may be sent by the AMF according to the registration request of the UE, so that the AMF may process the registration request of the UE when the number of UEs currently located in the service area of the NSACF and registering the network slice does not exceed the sum of the first terminal device number quota and the first threshold, so that the UE successfully registers to the network slice.

When the policy enforcement function network element is an NSACF and the first policy information includes an access control rule that allows the number of sessions established through the network slice to be located in a service area of the NSACF to be greater than or equal to a first session number quota, the first processing performed by the NSACF includes: storing the information of the session of the network slice to be established or established, wherein the session to be established or established refers to the session corresponding to the session establishment request received by the SMF; and/or accepting the second quota reservation application in the case that the number of sessions currently located in the service area of the NSACF and established through the network slice does not exceed the sum of the first quota of sessions and the second threshold. The SMF may be configured to send the session establishment request according to the session establishment request, so that the SMF may process the session establishment request for requesting to establish the session of the network slice when the session is currently located in the service area of the NSACF and the number of sessions established through the network slice does not exceed the sum of the first session number quota and the second threshold, so that the session of the network slice may be established.

The following describes a communication method provided in the embodiments of the present application with reference to examples.

Example 1

In the scenario shown in example 1, the communication method provided by the embodiment of the present application may be performed by interaction of AMF, NSACF1, NSACF2 and PCF. Wherein, the network slice department marked by S-NSSAI belongs to and only deploys the NSACF1 and the NSACF2, wherein the service area of the NSACF1 and the service area of the NSACF2 are different service areas, and are respectively marked as a service area 1 and a service area 2. The PCF may be configured to determine policy information for the network slice, i.e., determine the first policy information. The number of AMFs may be one or more, and the AMFs may query the PCF corresponding to the network slice according to local configuration or from the NRF. In example 1, if the number of AMFs is multiple, for example, the AMFs include AMF1 and AMF2, where AMF1 is an AMF in a service area of NSACF1, and AMF2 is an AMF in a service area of NSACF2, and AMF1 is used as an example hereinafter.

In example 1, the method may include the following steps shown in fig. 4:

s201: and the PCF inquires the information of all the NSACFs deployed by the network slice to which the S-NSSAI belongs from the S-NSSAI to the NRF to obtain the access information of the NSACF1 and the access information of the NSACF 2. In this application, the access information may be information such as an interface identifier or an address.

S202: the PCF subscribes to the number of UEs within service area 1 of the NSACF1 for the network slice, and subscribes to the number of UEs within service area 2 of the NSACF2 for the network slice.

Optionally, in step S202, subscribing means that the PCF sends a request message to the NSACF1 and/or the NSACF 2. The S-NSSAI may be carried in the request message.

In one possible implementation, the request message may be used to request NSACF1 and/or NSACF2 to send the first information when it is determined that the first condition is satisfied. In example 1, the first condition and the first information may relate to a number of UEs registering the network slice within a service area of the NSACF. Taking NSACF1 as an example, the first information may be used to indicate that the number of UEs registered for the network slice within the service area of NSACF1 decreases to a third threshold or increases to a fourth threshold. In addition, the third threshold and/or the fourth threshold may be a value predefined by a protocol or the like, pre-configured to be determined, or a value indicated by the PCF, where if the value is indicated by the PCF, the third threshold and/or the fourth threshold may be carried in the request message, or may be carried in other messages sent by the PCF, which is not particularly limited.

In a further possible example, the request message may be used to request that NSACF1 and/or NSACF2 send the second information when it is determined that the second condition is satisfied. The request message may be used to indicate a time condition for sending the second information, and the time condition may be predefined by a protocol or the like, a value determined by pre-configuration, or may be indicated by the PCF through a message other than the request message. Alternatively, the request message may be request information of the second information for the NSACF1 and/or the NSACF2 to perform transmission of the second information in response to the request message.

In addition, the NSACF1 and/or the NSACF2 may send the PCF the number of UEs currently registered with the network slice in the respective service area after each reception of a request message from the PCF. Thereafter, the NSACF1 and/or the NSACF2 may also transmit the first information after a first condition indicated by the request message is satisfied, and/or transmit the second information after a second condition is satisfied.

Accordingly, the PCF may obtain the number of UEs registered for the network slice in service area 1 from the NSACF1 and the number of UEs registered for the network slice in service area 2 from the NSACF 2.

S203: the PCF determines the total number (i.e., the first number) of UEs registering the network slice from the number of UEs registering the network slice in service area 1 and the number of UEs registering the network slice in service area 2.

For example, when the ratio of the total number of UEs currently registered in the network slice to the maximum number of registered terminal devices in the network slice exceeds a specific threshold (e.g., 80%), it is determined that the policy information corresponding to the entire network slice is active EAC, that is, the policy information corresponding to all nsafs deployed in the network slice is used to indicate that the number of UEs registered in the network slice in the service area of an NSACF is not allowed to exceed the limit of the number of first terminal devices in the service area; otherwise, if the threshold is not exceeded, it may be determined that the policy information corresponding to the entire network slice is to deactivate EAC, that is, the PCF may determine that the policy information corresponding to all the nsefs deployed in the network slice is used for indicating that the number of UEs registered to the network slice in the service area of an nsecf is allowed to exceed the first terminal device number limit in the service area. In addition, the determination process of the policy information may also consider a time period, for example, the PCF may determine the policy information indicating to activate the EAC when determining that the policy information corresponding to the entire network slice is activated EAC in a time period with a large traffic of the network slice, such as ten to eleven am, and determine the policy information indicating to deactivate EAC in other time periods.

The PCF may also determine policy information of the service area of a certain NSACF according to the number of currently registered terminal devices in the service area of the NSACF, for example, when the number of terminal devices registered in the service area 1 of the NSACF1 for a slice reaches a specific value, for example, 5000, it is determined that the policy information corresponding to the service area 1 indicates activation of the EAC.

For example, when the number of UEs registered in the service area 1 for the network slice is different from the number of UEs registered in the service area 2 for the network slice, the PCF may determine corresponding first policy information for the NSACF1 and determine corresponding first policy information for the NSACF2, respectively, and the specific implementation manner may be as described in the foregoing manner 1.

Optionally, if the PCF determines that the number of UEs allowed to register the network slice in the service area of a certain NSACF exceeds the first terminal device number quota in the service area, the PCF may send an indication to the NSACF, that is, indicate to the NSACF that the number of UEs allowed to register the network slice in the service area exceeds the first terminal device number quota, and/or indicate a first threshold value, where the NSACF is configured to determine whether to accept the first quota reservation application sent by the AMF when the number of UEs allowed to register the network slice in the service area exceeds the first terminal device number quota. Wherein the difference between the number of UEs registered to the network slice in the service area of the NSACF and the first terminal device number quota, such as the maximum number of UEs registered to the network slice in the service area under normal conditions, does not exceed the first threshold. For example, the first threshold value may be a set value greater than the first terminal device quantity limit, or a value determined according to the first terminal device quantity limit.

S204: after AMF1 is started, determining policy information that the PCF needs to subscribe the network slice to the PCF according to local configuration, or after AMF1 receives a first registration request carrying the S-NSSAI from the UE, determining policy information that the PCF subscribes the network slice to the PCF, or determining that a function switch for executing access control on the network slice is turned on by AMF 1. In other words, AMF1 may determine a slice policy association (slice policy association) between itself and the PCF for establishing the network slice.

Among them, the AMF1 may obtain access information of the PCF through configuration or through NRF.

S205: AMF1 sends a first request to PCF, wherein the S-NSSAI is carried in the first request. The first request may be for subscription policy information.

Optionally, the first request may carry policy information for subscribing to the number of registered UEs for the network slice.

S206: the PCF may accept the subscription of the AMF1 to the policy information of the network slice, and send a response message corresponding to the first request to the AMF 1. Alternatively, the PCF may determine a slice policy association between it and AMF1 that establishes the network slice.

S207: the PCF sends the first policy information of the network slice to AMF1 and/or NSACF1.

The first policy information may be determined according to policy configuration information from a network element (e.g., UDM and/or AF) of a network slice policy configuration function, which is specifically referred to in the description of the present application. Optionally, the first policy information may include an access control rule.

For example, the PCF may send first policy information to the AMF1 and the nsecf 1, and after the AMF1 receives the registration request carrying the S-nsaii, if it is determined that the EAC mechanism is in the active state according to the first policy information, apply for the UE registration quota from the nsecf 1. If the NSACF1 determines that the EAC mechanism is in an activated state according to the first policy information, the NSACF1 only receives the message of applying for UE registration quota sent by the AMF1 when the number of the UE which registers the network slice in the self service area does not exceed the first terminal equipment number quota. If the EAC mechanism is determined to be in the deactivated state according to the first policy information, AMF1 may accept the registration request first, and after the registration request is successfully processed, AMF1 sends information of the successfully registered terminal device to NSACF1. The NSACF1 determines that the EAC mechanism is in a deactivation state according to the first strategy information, even if the number of the UE registering the network slice in the self service area exceeds the first terminal equipment number limit, the NSACF1 records the information of the successfully registered terminal equipment transmitted by the AMF1 and increases the number of the UE registering the network slice in the self service area.

Alternatively, the PCF transmits the first policy information to the NSACF1. Wherein, the first policy information includes that the number of UEs registering the network slice in the NSACF1 service area is allowed to exceed the first terminal device number quota, and the first policy information may further include indication information of a first threshold, which may be referred to as the description of the first threshold in S203. Taking the sum of the first threshold and the first terminal device quantity limit as the maximum quantity of the UEs registered to the network slice in the service area of the NSACF1 as an example, after receiving the registration request carrying the S-NSSAI, the AMF1 applies for the UE registration quota to the NSACF1, and the NSACF1 still applies for the UE registration quota to the receiving AMF1 even if the quantity of the UEs registering the network slice in its own area exceeds the first terminal device quantity limit according to the first policy information. The NSACF1 refuses the AMF1 to apply for the UE registration quota only when the number of the UE which registers the network slice in the self area exceeds the sum of the first threshold and the first terminal equipment number quota. The AMF1 determines whether to process the registration request according to the response message returned by the NSACF1.

In S207, the first policy information may correspond to the network slice, e.g., the first policy information for all nsafcs of the network slice indicates that EAC is activated. Alternatively, the first policy information may correspond to a certain NSACF, e.g., for the same network slice, the first policy information of a certain (or some) NSACF may indicate activation of EAC, and the first policy information of some other NSACF may indicate deactivation of EAC. If the first policy information corresponds to a certain NSACF, the PCF sends the first policy information to AMF1 in the service area of the NSACF.

The PCF may determine the first policy information according to the service area of the nsecf to which the AMF belongs. The PCF may send the identifier of the nsecf to the NRF to query the AMF in the service area of the nsecf.

If the AMF belongs to NSACF1, the PCF transmits the first policy information corresponding to the NSACF1 to the AMF in S207. If the AMF belongs to the NSACF2, the PCF transmits the first policy information corresponding to the NSACF2 to the AMF in S207. For example, the first policy information corresponding to the NSACF1 is different from the first policy information corresponding to the NSACF2 according to the difference between the number of UEs registering the network slice in the service area of the NSACF1 and the number of UEs registering the network slice in the service area of the NSACF2, and the first policy information corresponding to the NSACF1 is different from the first policy information corresponding to the NSACF 2.

Optionally, the first policy information may be carried in a policy notification message, and the policy notification message may also carry an identifier of the network slice.

Optionally, the PCF may further send policy information to the NSACF indicating whether the number of UEs registering the network slice within the service area of the NSACF is allowed to exceed the first UE quota.

It should be understood that the first policy information may be sent by the PCF in response to the first request, or may be sent in response to a change in the policy information of the network slice and/or the policy information corresponding to the NSACF, for modifying the existing policy information of the AMF 1.

It should be understood that the first policy information related to S207 can be referred to the description in the present application, and is not specifically expanded here.

S208: after receiving the first policy information, the AMF1 activates or deactivates the EAC according to the first policy information.

S209: when AMF1 receives the registration request carrying the S-NSSAI, the state of the current EAC mechanism is identified to be activated or inactivated, and corresponding processing is executed. The registration request may be used to request registration of the UE to the network slice.

In S209, if the first policy information is used to indicate activation of EAC, AMF1 needs to send a first quota reservation application to NSACF1, so as to check and update the number of UEs registering the network slice in the service area of NSACF1, request a quota reservation for registration of the UE, and receive a feedback result of NSACF1. If the feedback result indicates that the NSACF1 accepts the first quota reservation application, the AMF1 may process the registration request to complete registration of the UE on the network slice; if the feedback result indicates that the NSACF1 does not accept the first quota reservation application, the AMF1 refuses to register the UE to the network slice. The NSACF1 may determine whether to accept the first quota reservation application according to the number of UEs that have registered the network slice in the service area of the NSACF, policy information on whether the number of UEs that are allowed to register the network slice in the service area exceeds the first terminal device number quota, or indication information of a first threshold. The first threshold value can be referred to the explanation of the first threshold value in S203.

If the first policy information is used to indicate deactivation of EAC, AMF1 may process the registration request.

In addition, if EAC is deactivated, after AMF1 processes the registration request and completes registration of the UE, if the S-nsai is included in the nsaai assigned by AMF1 to the UE, an indication message needs to be sent to NSACF1, so that NSACF1 increases the number of UEs registered to the network slice in its service area by 1. The first quota reservation application may also be used to request NSACF1 to increase the number of UEs within its service area that have registered to the network slice by 1 if EAC is activated. Alternatively, NSACF1 may increase the number of UEs within its service area that have registered to the network slice by 1 in response to the first quota reservation application.

Based on the method shown in fig. 4, when a network slice is deployed with multiple nsefs, the PCF can determine policy information according to the current operating condition of the entire network slice and/or the operating condition of the service area of the nsecf, to determine whether to allow the UE to register to the network slice, so as to implement flexible control of the UE accessing the network slice.

It should be understood that as the number of UEs registering the network slice increases, which may result in a change of the first policy information, the PCF may send the updated first policy information to the AMF1 and/or the NSACF according to the subscription to the number of UEs registering the network slice within the service area of the NSACF, so that the AMF and/or the NSACF performs control of the UE registration process according to the updated first policy information, and a specific flow may be performed with reference to fig. 4, and is not expanded in detail.

Example 2

In the scenario shown in example 2, the communication method provided by the embodiment of the present application may be performed by the SMF, the NSACF1, the NSACF2, and the PCF. Wherein, the network slice department marked by S-NSSAI belongs to and only deploys the NSACF1 and the NSACF2, wherein the service area of the NSACF1 and the service area of the NSACF2 are different service areas, and are respectively marked as a service area 1 and a service area 2. The PCF may be operable to determine policy information for the network slice, i.e., determine the first policy information. The number of SMFs may be one or more, and the SMFs may query the PCF corresponding to the network slice according to local configuration or from the NRF. In example 2, if the number of SMFs is multiple, for example, the SMFs include SMF1 and SMF2, where SMF1 is an SMF in the service area of NSACF1, and SMF2 is an SMF in the service area of NSACF2, and the SMF1 is taken as an example hereinafter.

In example 2, the method may include the following steps shown in fig. 5:

s301: and the PCF inquires the information of all the NSACFs deployed by the network slice to which the S-NSSAI belongs from the S-NSSAI to the NRF to obtain the access information of the NSACF1 and the access information of the NSACF 2.

S302: the PCF subscribes to the number of sessions established through the network slice within service area 1 from NSACF1 and subscribes to the number of sessions established through the network slice within service area 2 from NSACF 2.

S202 may be referred to for implementation of S302.

The PCF may determine the first policy information corresponding to the NSACF1 and the first policy information corresponding to the NSACF2 according to the number of sessions established through the network slice in the service area 1 and/or the number of sessions established through the network slice in the service area 2.

For example, at 10 to 11 am each day, only if the number of sessions established through the network slice for service area 1 is close to 6000 (or other values), the first policy information corresponding to NSACF1 may be used to indicate that EAC is activated; in other time periods, when the number of sessions established through the network slice in the service area 1 is close to 5000, the first policy information corresponding to the NSACF1 may be used to indicate that the EAC is activated; in other cases, the first policy information corresponding to NSACF1 is used to indicate deactivation of EAC.

For another example, in other time periods, if the number of PDU sessions in service area 2 is much less than 4000, the slice PCF may indicate activation of EAC only when the number of PDU sessions in service area 1 is close to 6000, and otherwise, the first policy information corresponding to NSACF1 may indicate deactivation of EAC. Therefore, the idle resources of the network slices can be fully utilized, and more sessions can be established as far as possible before the network slices reach the maximum number of sessions as a whole.

The PCF may also indicate, via the first policy information, to use a new charging key or to use default QoS parameters for the specified PDU session.

S303: after SMF1 starts, SMF1 may determine, according to the local configuration, that it needs to subscribe to the policy information of the network slice to the PCF, or, after receiving the first session establishment request related to the S-NSSAI, SMF1 subscribes to the policy information of the network slice to the PCF, that is, sends the first request. Alternatively, SMF1 may determine a slice policy association between it and the PCF that establishes the network slice.

Wherein, the SMF1 can obtain the access information of the PCF through configuration or through NRF.

S304: and after receiving the subscription of the SMF1 to the policy information of the network slice, the PCF sends the first policy information of the network slice to the SMF1 and/or the NSACF1.

The PCF may also send a response message corresponding to the first request to the SMF1 after accepting the subscription of the SMF1 for the policy information of the network slice.

If the first policy information does not include the access control rule, for example, the first policy information is a service processing parameter of a network slice and/or a charging key value corresponding to the network slice, the PCF may send the first policy information to the SMF 1.

If the first policy information includes the access control rule, the PCF may send the first policy information to the NSACF1, and optionally, may also send the first policy information to the SMF 1.

For example, the PCF may send first policy information carrying the access control rule to the SMF1 and the nsecf 1, and after the SMF1 receives the session establishment request carrying the S-nsai, if it is determined that the EAC mechanism is in an active state according to the first policy information, apply for the session establishment quota from the nsecf 1. If the NSACF1 determines that the EAC mechanism is in an active state according to the first policy information, the NSACF1 accepts the message for applying the session quota, which is sent by the SMF1, only when the number of sessions established in the network slice in the self service area does not exceed the first session number quota. If the EAC mechanism is determined to be in the deactivation state according to the first strategy information, the SMF1 can firstly accept the session establishment request, and after the session establishment request is successfully processed, the SMF1 sends the information of successfully establishing the session to the NSACF1. The NSACF1 determines that the EAC mechanism is in a deactivation state according to the first strategy information, even if the number of the established sessions in the network slice in the self service area exceeds the first session number quota, the NSACF1 records the information of the successfully established sessions sent by the SMF1 and increases the number of the established sessions in the network slice in the self service area.

Alternatively, the PCF transmits the first policy information to the NSACF1. Wherein the first policy information includes an access control rule that the number of sessions established in the network slice in the NSACF1 service area is allowed to exceed a first session number limit, and the first policy information may further include indication information of a second threshold. Wherein the difference between the number of sessions established through the network slice in the service area of NSACF1 and the first session number quota, such as the maximum number of sessions established through the network slice in the service area in a normal case, does not exceed the second threshold value.

Taking the example that the difference between the number of sessions established through the network slice in the service area of the NSACF1 and the first session number limit does not exceed the second threshold, after the SMF1 receives a session establishment request carrying S-NSSAI, the session quota is applied to the NSACF1, and the NSACF1 accepts the SMF1 to apply for the session quota even if the number of sessions established through the network slice in the self area exceeds the first session number limit according to the first policy information. The NSACF1 rejects the SMF1 to apply for the session quota only if the sum of the second threshold and the first session number quota is exceeded. The SMF1 determines whether to process the session establishment request according to the response message returned by the NSACF1.

The first policy information may be determined according to policy configuration information from a network element (e.g., UDM and/or AF) of a network slice policy configuration function, which is specifically referred to in the description of the present application.

In addition, the first policy information may be determined according to the number of sessions registered through the network slice in the service area 1 and/or the service area 2 acquired in S302, and specifically, refer to the description in S302.

In S304, the first policy information may correspond to the network slice, e.g., the first policy information for all nsafcs of the network slice indicates that EAC is activated. Alternatively, the first policy information may correspond to a certain NSACF, e.g., for the same network slice, the first policy information of a certain (or some) NSACF may indicate activation of EAC, and the first policy information of some other NSACF may indicate deactivation of EAC. If the first policy information corresponds to a certain NSACF, the PCF sends the first policy information to the SMF in the service area of the NSACF.

It should be understood that the first policy information may be sent by the PCF in response to the first request, or may be sent in response to a change in the policy information of the network slice and/or the policy information corresponding to the NSACF, for modifying the existing policy information of the SMF.

S305: optionally, the NSACF1 may establish a slice policy association with the PCF, and the PCF sends the first policy information corresponding to the NSACF1. Fig. 5 illustrates the NSACF1 as an example, but not limited thereto.

Alternatively, S305 may be executed before or after S304, or S304 and S305 may be executed simultaneously, without particular limitation.

S306: and after receiving the session establishment request carrying the S-NSSAI, the SMF1 identifies whether the current EAC mechanism is activated or not according to the first strategy information, and executes corresponding processing.

If the first policy information is used to indicate that the EAC is activated, the SMF1 needs to send a second quota reservation application to the NSACF1, a request message for checking and updating the number of sessions established through the network slice in the service area of the NSACF1, request a quota reservation for establishment of the session, and receive a feedback result of the NSACF1. The feedback result of the NSACF1 may be used to indicate whether the NSACF1 accepts the second quota reservation application, and if the feedback result indicates that the NSACF1 accepts the first quota reservation application, the SMF1 may process the session establishment request to complete establishment of the session.

The second quota reservation application may carry an identifier of the UE requesting to establish the Session and/or an identifier of the Session, where the identifier of the UE is, for example, a user permanent identifier (SUPI) of the UE, and the identifier of the Session is, for example, a PDU Session identifier (Session ID).

If the feedback result indicates that the NSACF1 does not accept the second quota reservation application, the SMF1 refuses to establish the session. The NSACF1 may determine whether to accept the first quota reservation application according to the number of sessions established by the network slice in the service area of the NSACF, policy information on whether the number of sessions established by the network slice in the service area is allowed to exceed the first quota of sessions, or indication information of a second threshold. The second threshold value is described with reference to the second threshold value in S304.

If the first policy information is used to indicate deactivation of the EAC, then SMF1 may process the registration request.

Furthermore, if EAC is deactivated, after SMF1 processes the session establishment request and completes the establishment of the session, SMF1 needs to send an indication message to NSACF1, so that NSACF1 increases the number of sessions established through the network slice in its service area by 1. The second quota reservation application may also be used to request NSACF1 to increase the number of sessions established over the network slice within its service area by 1 if EAC is activated. Alternatively, NSACF1 may increase the number of sessions established through the network slice within its service area by 1 in response to the second quota reservation application.

Based on the method shown in fig. 5, when a network slice is deployed with multiple nsafcs, the PCF can determine policy information according to the current operating condition of the entire network slice and/or the operating condition of the service area of the NSACF to decide whether to allow the session of the network slice to be established, thereby implementing flexible control over the establishment process of the session of the network slice.

It should be understood that as the number of sessions established through the network slice increases, which may result in a change of the first policy information, the PCF may send the updated first policy information to the SMF1 and/or the NSACF according to the subscription for the number of sessions established through the network slice within the service area of the NSACF, so that the SMF1 and/or the NSACF performs control of the session establishment process according to the updated first policy information, and a specific flow may be performed with reference to fig. 5 and is not specifically developed.

Example 3

In example 3, the communication method provided by the embodiment of the present application may be performed by AMF, SMF, NSACF, UDR, AF, and PCF. Wherein, the number of AMF, SMF and/or NSACF can be one or more. In this embodiment, the AF may obtain current status information of the network slice from the PCF, for example, obtain the current number of registered users of the network slice or the current number of PDU sessions. If multiple NSACFs exist, the multiple NSACFs are deployed in the same network slice.

Optionally, the AF may further obtain policy information corresponding to the current network slice, or policy information corresponding to the NSACF in the network slice, for example, the AF may know that the number of UEs currently allowed to register in the network slice exceeds the limit.

The UDR may store policy configuration information for the network slice, and the AF may set or modify configuration information associated with the network slice and send the new configuration information to the PCF. The application configuration information includes, for example, configuration information of the number of UEs allowed to register the network slice exceeding, and/or QoS parameters or charging key values after the number of UEs of the network slice exceeding is set. The PCF may determine policy information of the network slice according to the application configuration information, and perform the method provided by the embodiments of the present application.

As shown in fig. 6, the method may include the steps of:

s401: the PCF subscribes (or requests) to each NSACF for status information of a certain network slice within the service area of the NSACF, respectively. The state information includes the number of registered terminal devices currently registered in the service area of each NSACF, or the number of sessions established through the network slice. Implementation can refer to S201-S202, S301-S302, and/or the present application is a description of method embodiment portions.

S402: the NSACF sends a notification message to the PCF, wherein the notification message carries the state information of the network slice in the service area of the NSACF.

S403: the PCF obtains the state information of the whole network slice according to the state information of the network slice obtained from each NSACF, and determines first strategy information according to the state information of the whole network slice. Wherein the first policy information corresponds to the network slice.

For example, the first policy information is used to indicate, for example, whether to allow for over-registration of the UE or establishment of a session.

The manner of determining the first policy information may refer to S207, S304 or the description of the determination manner of the first policy information in the embodiment section of the present application.

S404: and the AF sends a network slice strategy information opening request to the PCF, wherein the network slice strategy information opening request carries the S-NSSAI of the network slice.

For example, when the AF needs to confirm whether the first policy information currently being executed meets the service requirement, or the like, the AF sends the network slice policy information release request. The service requirement is, for example, a QoS requirement or a charging key requirement, etc.

Where the AF may access the PCF directly or through the NEF to send the request. The AF or NEF may obtain access information for the PCF via local configuration, or by querying the NRF based on S-NSSAI.

Optionally, S404 may be executed before or after S403, or S404 and S405 may be executed simultaneously, which is not particularly limited in this application.

S405: in response to the network slice policy information opening request, the PCF sends the AF the status information and/or the first policy information of the network slice.

By the method shown in fig. 6, the AF may acquire the state information or the first policy information of the network slice, thereby implementing network function opening. The state information of the network slice may be used for the AF to determine new policy information of the network slice, where the new policy information may be the same as or different from the first policy information, or the state information of the network slice may be used for the AF to determine policy configuration information, where the policy configuration information may be used to determine new policy information of the network slice, for example, the AF may store the policy configuration information in the UDR, and is used for the PCF to determine the new policy information of the network slice after obtaining the policy configuration information from the UDR. The AF may determine whether to modify the first policy information based on the first policy information.

In the scenario shown in example 3, a decision process of the policy information of the network slice where the AF affects the PCF is also supported, or in other words, a decision process of the policy information of the network slice where the AF affects the PCF is supported to provide a suggestion.

As shown in fig. 7, at this time, the communication method provided in the embodiment of the present application may include the following steps:

s501: the AF sends a setup request for application configuration information to the UDR, which may carry policy configuration information for the application and the S-NSSAI carrying the network slice of the application. Wherein the policy configuration information of the application is usable to indicate at least one of: whether to allow over-registration of the UE or to establish a session, a first threshold, a second threshold, a QoS parameter, or a charging key.

Wherein, if the applied policy configuration information indicates a first threshold, a difference between the number of UEs registered to the network slice located in the service area of the NSACF and a first terminal device number quota, such as a maximum number of UEs registered to the network slice in the service area in a normal case, does not exceed the first threshold. For example, the first threshold may be a set value greater than the first terminal device number limit, or a value determined according to the first terminal device number limit. If the applied policy configuration information indicates a second threshold, the number of sessions established through the network slice within the service area of the NSACF does not differ by more than the second threshold from a first session number limit, e.g., a maximum number of sessions established through the network slice within the service area under normal circumstances.

For an example, the first threshold may be referred to in S207 for the description of the first threshold.

For example, the policy configuration information for the application may indicate that the number of PDU sessions that the application is allowed to establish exceeds the maximum number of sessions for the network slice by up to 20%, and indicate the demand of the application for network quality after overrun.

S502: the UDR stores policy configuration information and S-NSSAI for the application.

S503: and the PCF acquires the policy configuration information of the application from the UDR according to the S-NSSAI.

For example, the PCF sends the S-NSSAI of the network slice to the UDR and receives policy configuration information for the application from the UDR.

S504: and the PCF determines the first strategy information of the network slice according to the applied strategy configuration information.

For example, if the policy configuration information of the application allows the number of PDU sessions established by the application to exceed 20% of the maximum number of sessions of the network slice at most, the first policy information may indicate that the EAC is activated after the number of PDU sessions of the network slice reaches a certain value (e.g., the maximum number of sessions of the network slice); for another example, if the policy configuration information of the application indicates a requirement of the application for network quality after the overrun, the first policy information may further indicate to use a new charging key value or to use a default QoS parameter of the specified session after the number of PDU sessions of the network slice reaches or exceeds the maximum number of sessions of the network slice.

S505: the PCF sends the determined first policy information to the AMF, SMF and/or NSACF.

For the first policy information sending manner, reference may be made to the description in this application.

With the method of fig. 7, configuration information for a proposed or supported application may be sent by the AF to the UDR, providing a reference or basis for the PCF to determine the first policy information based on the configuration information obtained from the UDR.

By the method provided by the embodiment of the application, the policy decision function network element can determine the first policy information of the network slice and send the first policy information to the policy execution function network element, so that the policy execution function network element executes the first processing according to the first policy information, and the flexibility of managing the service accessing the network slice can be improved. The first policy information may include at least one of an access control rule of the network slice, a traffic processing parameter, or a charging key value corresponding to the network slice. For example, in a scenario where multiple nsadcfs exist and each NSACF controls a part of an area, each NSACF may obtain first policy information from a PCF, and each NSACF performs corresponding processing in the area controlled by each NSACF according to the received first policy information, instead of performing the same processing on a service accessing the whole network slice according to the same control policy, so that flexibility can be improved.

Wherein the access control rule may be used to indicate whether a UE in a service area of a policy enforcement function network element is allowed to register to the network slice, or to indicate whether a session is allowed to be established through the network slice in the service area of the policy enforcement function network element, or to indicate whether an over-provisioning of a UE to the network slice is allowed in the service area of the network slice or a certain nsaf of the network slice, or to indicate whether an over-provisioning of a session of the network slice is allowed in the service area of the network slice or a certain nsaf of the network slice. To further increase the flexibility of access management for network slices.

Based on the same concept, the present application also provides a communication device to execute the actions executed by the policy enforcement function network element and the policy decision function network element in the above embodiments. In order to implement each function in the method provided by the embodiment of the present application, the policy execution function network element and the policy decision function network element may include a hardware structure and/or a software module, and implement each function in the form of a hardware structure, a software module, or a hardware structure plus a software module. Whether any of the above-described functions is implemented as a hardware structure, a software module, or a hardware structure plus a software module depends upon the particular application and design constraints imposed on the technical solution.

It should be understood that, in the embodiment of the present application, the device may be divided into functional modules according to the method example described above, for example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. It should be noted that, in the embodiment of the present application, the division of the module is schematic, and is only one logic function division, and there may be another division manner in actual implementation.

As shown in fig. 8, a communication apparatus provided in an embodiment of the present application may include a communication module 801 and a processing module 802, where the communication module 801 and the processing module 802 are coupled to each other. The communication device 800 may be used to perform the steps performed by the policy enforcement function network element or the policy decision function network element shown in fig. 3-7 above. The communication module 801 may be used to support the communication device 800 to perform the communication actions in the method embodiments, and the communication module 801 may also be referred to as a communication unit, a communication interface, a transceiver module, or a communication unit. The communication module 801 may have a wireless communication function, and may communicate with another communication device by a wireless communication method, for example. For example, the communication module 801 may perform the sending and/or receiving actions of the policy enforcement function network element or the policy decision function network element in the examples shown in fig. 3-7.

The processing module 802 may also be referred to as a processing unit, and may be configured to support the communication apparatus 800 to perform the processing actions of the session management network element in the above method embodiments, including but not limited to: generate information, messages, and/or process signals received by the communication module 801, etc. For example, the processing module 802 may perform actions other than sending and/or receiving actions of the policy enforcement function network element or the policy decision function network element in the examples shown in fig. 3-7.

For example, in performing the steps performed by the policy enforcement function network element in the above method embodiments, the communication module 801 may be configured to send a first request to the policy decision function network element. The communication module 801 may be further configured to receive first policy information from the policy decision function network element. The processing module 802 may be configured to perform a first process according to the first policy information.

In a possible example, before sending the first request, the communication module 801 may be further configured to receive a session establishment request from the terminal device, where the session establishment request carries an identifier of the network slice. The first policy information includes the service processing parameter of the network slice, and the processing module 802 may be configured to set the service processing parameter of the session of the terminal device to the service processing parameter of the network slice. And/or if the first policy information includes a charging key of the network slice, the processing module 802 may be configured to set the charging key of the session of the terminal device as the charging key corresponding to the network slice.

In one possible example, if the policy enforcement function network element includes an NSACF, and the first policy information includes an access control rule for the network slice, the access control rule including an allowance that the number of terminal devices located within the service area of the policy enforcement function network element and registered to the network slice exceeds a first terminal device number limit, the processing module 802 may be configured to store information of terminal devices to be registered or already registered to the network slice when the number of terminal devices located within the service area of the policy enforcement function network element and registered to the network slice is greater than or equal to the first terminal device number limit, and/or accept a first quota reservation application requesting a reservation of a registration quota for the network slice for the terminal devices to be registered to the network slice, or the communication module 801 may be configured to send a response message indicating receipt of the first quota reservation application.

In one possible example, the first policy information may further include indication information of a first threshold, the processing module 802 may be further configured to determine that the number of terminal devices located in the service area of the policy enforcement function network element and registered to the network slice differs from the first terminal device number quota by no more than the first threshold, and thereafter, the processing module 802 may accept the first quota reservation application, or the communication module 801 may be configured to send a response message indicating that the first quota reservation application is received. Wherein, if the policy enforcement function network element is an NSACF, a difference between the number of UEs registered to the network slice in a service area of the policy enforcement function network element and a first terminal device number limit, for example, a maximum number of UEs registered to the network slice in the service area under a normal condition, does not exceed a first threshold.

In one possible example, if the first policy information includes an access control rule for the network slice, the access control rule including a number of sessions established through the network slice within a service area of the policy enforcement function network element that exceeds a first number of sessions quota, and the policy enforcement function network element includes an NSACF, when the number of sessions established through the network slice within the service area of the policy enforcement function network element is greater than or equal to the first number of sessions quota, the processing module 802 may store information of sessions to be established or established through the network slice, and/or accept a second quota reservation application requesting to establish a quota for the sessions to be established through the network slice, or the communication module 801 may be configured to send a response message indicating receipt of the second quota reservation application.

In a possible example, the first policy information may further include indication information of a second threshold, and the processing module 802 may be further configured to determine that a number of sessions established through the network slice within a service area of the policy enforcement function network element does not differ from the first quota of number of sessions by more than the second threshold, and thereafter, the processing module 802 may accept the second quota reservation application, or the communication module 801 may be configured to send a response message indicating that the second quota reservation application is received. Wherein, if the policy enforcement function network element is an NSACF, the difference between the number of sessions established through the network slice in the service area of the policy enforcement function network element and a first session number quota, such as the maximum number of sessions established through the network slice in the service area under normal conditions, does not exceed a second threshold.

In one possible design, where the policy enforcement function network element includes an NSACF, the communication module 801 may further send first information to the policy decision function network element when the first condition is satisfied, where the first information is used to indicate that the first condition is satisfied. The first condition may include the number of UEs of the registered network slice located within the service area of the NSACF decreasing to a third threshold, and thus, the PCF may determine from the received first information that the number of UEs of the registered network slice currently located within the service area of the NSACF is the third threshold.

Alternatively, the first condition may include that the number of UEs of the registered network slice located within the service area of the NSACF increases to a fourth threshold, and thus, the PCF may determine, from the received first information, that the number of UEs of the registered network slice currently located within the service area of the NSACF is the fourth threshold.

Alternatively, the first condition may include that the number of sessions established through the network slice located within the service area of the NSACF is reduced to a fifth threshold, and thus, the PCF may determine, from the received first information, that the number of sessions established through the network slice located within the service area of the NSACF is the fifth threshold.

Alternatively, the first condition may include that the number of sessions established through the network slice located within the service area of the NSACF increases to a sixth threshold, and thus, the PCF may determine the number of sessions established through the network slice located within the service area of the NSACF to be the sixth threshold according to the received first information.

In one possible design, if the policy enforcement function network element includes an NSACF, the communication module 801 may further send a second message to the policy decision function network element when a second condition is satisfied. The second condition may be used to indicate the number of UEs registered for a network slice located within the service area of the NSACF. The second condition may comprise a time condition or request information comprising that the NSACF receives the second information from the policy decision function network element.

In one possible design, if the policy enforcement function network element includes an NSACF, the communication module 801 may further send third information to the policy decision function network element when a third condition is satisfied, the third information indicating a number of sessions established through the network slice and located within a service area of the policy enforcement function network element. The second condition may comprise a time condition or request information comprising that the NSACF receives the third information from the policy decision function network element.

In performing the steps performed by the policy decision function network element in the above method embodiments, the processing module 802 may be configured to determine the first policy information. The communication module 801 may be configured to send the first policy information to a policy enforcement function network element.

In one possible design, the communication module 801 may be further configured to receive a first request for the first policy information, or request to establish a connection for carrying the first policy information. The processing module 802 may determine the first policy information in response to the first request.

In one possible design, the communication module 801 may be further configured to receive policy configuration information from a network slice policy configuration function network element, and the processing module 802 may be configured to determine the first policy information according to the policy configuration information.

In one possible design, the processing module 802 may be further configured to determine the first policy information based on at least one of the first information and the second information. Wherein the first information is used for indicating that the first condition is satisfied. Wherein the first condition comprises: the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is reduced to a first threshold value; or, the number of terminal devices located in the service area of the policy enforcement function network element and registered with the network slice increases to the second threshold. The second information may be used to indicate the number of terminal devices located within the service area of the policy enforcement function network element and registered with the network slice.

In one possible design, processing module 802 may be further configured to determine the first policy information based on at least one of the first information and the third information. Wherein the first information is used for indicating that the first condition is satisfied. Wherein the first condition comprises: the number of sessions which are located in the service area of the policy enforcement function network element and are established through the network slice is reduced to a third threshold value; alternatively, the number of sessions established through the network slice and located within the service area of the policy enforcement function network element increases to a fourth threshold. The third information is used to indicate the number of sessions established through the network slice and located within the service area of the policy enforcement function network element.

In one possible design, processing module 802 may be further configured to obtain quantity information and determine the first policy information according to the quantity information. The quantitative information can be found in the description of the second aspect.

In one possible design, the processing module 802 may be further configured to determine a first number according to the number information, and determine the first policy information according to the first number, where the first number is the number of all terminal devices registered in the network slice, or the first number is the number of all sessions established through the network slice.

In one possible design, in a case that the first quantity indicates that the quantity of all sessions established through the network slice exceeds (or is not lower than) a seventh threshold, and is located within a service area of the policy enforcement function network element and the quantity of all sessions established through the network slice is lower than (or does not exceed) an eighth threshold, the first policy information includes a session establishment quota that reserves the network slice for the session to be established.

In one possible design, where the first number indicates that the number of all sessions established through the network slice is below (or does not exceed) a ninth threshold, the first policy information includes a number of sessions allowed to be located within a service area of the policy enforcement function network element and established through the network slice that exceeds a first session number limit.

In a possible design, the first number of sessions quota for a first time period is different from the first number of sessions quota for a second time period, and/or the ninth threshold value for the first time period is different from the ninth threshold value for the second time period.

In one possible design, the first policy information may further include indication information of a second threshold, and the difference between the number of sessions established through the network slice and the first number of sessions quota does not exceed the second threshold. The second threshold may determine a maximum number of sessions allowed to be established through the network slice within the service area, e.g., a difference between a number of sessions established through the network slice located within the service area of the policy enforcement function network element and a first number of sessions quota, e.g., a maximum number of sessions established through the network slice within the service area in a typical case, does not exceed the second threshold.

In one possible design, in a case that the first number indicates that the number of all terminal devices registered in the network slice exceeds (or is not lower than) a tenth threshold, and is located in a service area of the policy enforcement function network element and the number of terminal devices registered in the network slice is lower than (or does not exceed) an eleventh threshold, the first policy information includes reserving a registration quota for the terminal devices to be registered.

In one possible design, in a case where the first number indicates that the number of all terminal devices registered for the network slice is below (or does not exceed) a twelfth threshold, the first policy information includes a number of terminal devices allowed to be located within a service area of the policy enforcement function network element and registered for the network slice exceeding a first terminal device number limit.

In one possible design, the first terminal device quantity quota for a third time period is different from the first terminal device quantity quota for a fourth time period, or the twelfth threshold for the third time period is different from the twelfth threshold for the fourth time period.

In one possible design, the first policy information further includes indication information of a first threshold, and the difference between the number of terminal devices located in the service area of the policy enforcement function network element and the first terminal device number quota does not exceed the first threshold. The first threshold may be used to determine a maximum number of UEs allowed to register to the network slice within the service area, e.g., the number of UEs registered to the network slice that are located within the service area of the NSACF differs from the first terminal device number limit by no more than the first threshold. By adopting the design, the communication capacity of the network can be improved, excessive terminal equipment is prevented from being registered in the network slice, and the communication reliability is improved.

In one possible design, the first policy information includes that the number of terminal devices allowed to register to the network slice exceeds a second terminal device number quota, the policy enforcement function network element includes an NSACF; alternatively, the first policy information includes a number of sessions allowed for the network slice to exceed a second session number limit, and the policy enforcement function network element includes an NSACF.

In another possible implementation manner, the communication apparatus provided in the embodiments of the present application may also be formed by hardware components, such as a processor, a memory, or a transceiver, to implement the functions of the policy execution functional network element or the policy decision functional network element in the present application.

For ease of understanding, only the structure of the communication device 900 required to perform the methods described herein is shown in fig. 9, which is not intended to limit the scope of the invention to further components of the communication device. The communication device 900 may be configured to perform the steps performed by the policy enforcement function network element or the policy decision function network element in the above method embodiments. The communication device 900 may include a communication interface 901, a memory 902, and a processor 903. The communication interface 901 may be used for communication by a communication device, such as for sending or receiving signals. The memory 902 is coupled to the processor 903 and is operable to store programs and data necessary for the communication device 900 to perform various functions. The memory 902 is not necessarily a functional module included. The processor 903 is configured to support the communication apparatus 900 to perform processing functions performed by the policy enforcement function network element or the policy decision function network element in the above-described methods, such as determining to generate information, messages sent by the communication interface 901, and/or to demodulate and decode signals received by the communication interface 901, and so on. The memory 902 and the processor 903 may be integrated or separate.

Illustratively, the communication interface 901 may be a communication port, such as a communication port (or interface) for communication between network elements. The communication interface 901 may also be referred to as a transceiving unit or a communication unit.

The processor 903 may comprise a general-purpose Central Processing Unit (CPU), a microprocessor, an Application Specific Integrated Circuit (ASIC), or one or more ics for controlling the execution of programs in accordance with the teachings of the present disclosure. In particular implementations, communication device 900 may include multiple processors, as one embodiment. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, and/or processing cores that process data (e.g., computer program instructions).

The memory 902 may be, but is not limited to, a read-only memory (ROM) or other type of static storage device that may store static information and instructions, a Random Access Memory (RAM) or other type of dynamic storage device that may store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disk read-only memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.

For example, the above communication interface 901 may be used to perform the steps performed by the communication module 801 when performing the steps performed by the policy enforcement function network element in the above method embodiments. The processor 903 may be configured to perform the steps performed by the processing module 802, which are not described herein again. Similarly, the above communication interface 901 may be used to execute the steps executed by the communication module 801 when executing the steps executed by the policy decision function network element in the above method embodiment. The processor 903 may be configured to perform the steps performed by the processing module 802, which are not described herein again.

The communication apparatus 900 shown in fig. 9 may also be a chip or a system of chips or a circuit, for example, a chip in a policy enforcement function network element or a policy decision function network element. Optionally, when the communication device 900 is a chip or a circuit, the function/implementation process of the communication interface 9013 may also be implemented by a pin or a circuit.

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

The various illustrative logical units and circuits described in this embodiment of the application may be implemented or operated by general purpose processors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof. A general-purpose processor may be a microprocessor, but, in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration.

The steps of a method or algorithm described in the embodiments herein may be embodied directly in hardware, in a software element executed by a processor, or in a combination of the two. The software cells may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. For example, a storage medium may be coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC, which may be disposed in a terminal device. In the alternative, the processor and the storage medium may reside as discrete components in a terminal device.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Although the embodiments of the present application have been described with reference to specific features and embodiments thereof, it will be apparent that various modifications and combinations thereof may be made without departing from the spirit and scope of the embodiments of the present application. Accordingly, the present embodiments and figures are merely illustrative of the present embodiments as defined by the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the present embodiments. It will be apparent to those skilled in the art that various changes and modifications may be made in the embodiments of the present application without departing from the scope of the embodiments of the present application. Thus, if such modifications and variations of the embodiments of the present application fall within the scope of the claims of the embodiments of the present application and their equivalents, the embodiments of the present application are intended to include such modifications and variations as well.

Claims

1. A method of communication, comprising:

a policy decision function network element determines first policy information, wherein the first policy information comprises at least one of an access control rule of a network slice, a service processing parameter of the network slice or a charging key value corresponding to the network slice;

and the policy decision function network element sends the first policy information to a policy execution function network element, and the first policy information is used for the policy execution function network element to execute processing.

2. The method of claim 1, further comprising:

the policy decision function network element receives a first request, where the first request is used to request the first policy information, or the first request is used to request to establish a connection, and the connection is used to carry the first policy information.

3. The method of claim 1 or 2, wherein the determining, by the policy decision function network element, the first policy information comprises:

and the policy decision function network element determines the first policy information according to policy configuration information from a network slice policy configuration function network element.

4. The method of any of claims 1-3, wherein the determining, by the policy decision function network element, the first policy information comprises:

the policy decision function network element determines the first policy information according to at least one of first information and second information from the policy execution function network element;

wherein the second information is used to indicate the number of the terminal devices which are located in the service area of the policy enforcement function network element and register the network slice, the first information is used to indicate that a first condition is satisfied, and the first condition includes:

the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is reduced to a first threshold value; alternatively, the first and second liquid crystal display panels may be,

and the number of terminal devices which are positioned in the service area of the strategy execution function network element and register the network slice is increased to a second threshold value.

5. The method of any of claims 1-3, wherein the determining, by the policy decision function network element, the first policy information comprises:

the policy decision function network element determines the first policy information according to at least one of first information and third information from the policy execution function network element;

wherein the third information is configured to indicate the number of sessions established through the network slice and located in a service area of the policy enforcement function network element, and the first information is configured to indicate that a first condition is satisfied, where the first condition includes:

the number of sessions which are positioned in the service area of the strategy execution function network element and are established through the network slice is reduced to a third threshold value; alternatively, the first and second liquid crystal display panels may be,

the number of sessions located within the service area of the policy enforcement function network element and established through the network slice increases to a fourth threshold.

6. The method of any of claims 1-3, wherein the determining, by the policy decision function network element, the first policy information comprises:

the policy decision function network element obtains quantity information, where the quantity information is used to indicate the quantity of terminal devices that are located in a service area of each NSACF in one or more network slice access control function network elements NSACF and register the network slice, or is used to indicate the quantity of sessions that are located in the service area of each NSACF and are established through the network slice;

and the policy decision function network element determines the first policy information according to the quantity information.

7. The method of claim 6, wherein the determining, by the policy decision function network element, the first policy information based on the quantity information comprises:

the policy decision function network element determines a first number according to the number information, where the first number is the number of all terminal devices registered in the network slice, or the first number is the number of all sessions established through the network slice;

and the policy decision function network element determines the first policy information according to the first quantity.

8. The method of claim 7, wherein the first policy information comprises a session establishment quota that reserves the network slice for a session to be established, if the first number indicates that the number of all sessions established through the network slice exceeds a fifth threshold and is located within a service area of the policy enforcement function network element and the number of all sessions established through the network slice is below a sixth threshold.

9. The method of claim 7, wherein the first policy information includes an allowance of a number of sessions established through the network slice that are within a service area of the policy enforcement function network element that exceeds a first session number limit if the first number indicates that the number of total sessions established through the network slice is below a seventh threshold.

10. The method of claim 9, wherein the first limit on the number of sessions in a first time period is different from the first limit on the number of sessions in a second time period; alternatively, the seventh threshold value in the first time period is different from the seventh threshold value in the second time period.

11. The method according to claim 9 or 10, wherein the first policy information further comprises information indicative of an eighth threshold value, within a service area of the policy enforcement function network element and a difference between the number of sessions established through the network slice and the first session number quota does not exceed the eighth threshold value.

12. The method of claim 7, wherein in a case that the first number indicates that the number of all terminal devices registering the network slice exceeds a ninth threshold, and is located within a service area of the policy enforcement function network element and the number of terminal devices registering the network slice is below a tenth threshold, the first policy information comprises reserving a registration quota for terminal devices to be registered.

13. The method of claim 7, wherein in the event that the first number indicates that the number of all terminal devices registered for the network slice is below an eleventh threshold, the first policy information comprises a number of terminal devices allowed to be located within a service area of the policy enforcement function network element and registered for the network slice exceeding a first terminal device number limit.

14. The method of claim 13 wherein said first terminal device quantity quota for a third time period is different from said first terminal device quantity quota for a fourth time period; alternatively, the eleventh threshold value in the third time period is different from the eleventh threshold value in the fourth time period.

15. The method according to claim 13 or 14, wherein the first policy information further comprises information indicating a twelfth threshold value, and the difference between the number of terminal devices located within the service area of the policy enforcement function network element and registering the network slice and the first terminal device number quota does not exceed the twelfth threshold value.

16. The method of any one of claims 1-15,

the first policy information includes service processing parameters of the network slice, and the policy execution function network element includes a session management function network element SMF; alternatively, the first and second electrodes may be,

the first policy information includes a charging key value corresponding to the network slice, and the policy enforcement function network element includes an SMF.

17. The method of any one of claims 1-14 or 16,

when the number of the terminal devices registered to the network slice is smaller than the second terminal device number limit, the first policy information includes that the number of the terminal devices allowed to be registered to the network slice exceeds the second terminal device number limit, and the policy execution function network element includes an NSACF; alternatively, the first and second electrodes may be,

when the number of sessions established through the network slice is less than a second session number limit, the first policy information includes that the number of sessions established through the network slice exceeds the second session number limit, and the policy enforcement function network element includes an NSACF.

18. The method of any of claims 1-17, wherein the policy decision function network element comprises a PCF.

19. A method of communication, comprising:

a policy execution function network element sends a first request to a policy decision function network element, where the first request is used to request policy information of a network slice, or the first request is used to request to establish a connection, and the connection is used to carry the policy information of the network slice;

the policy execution function network element receives first policy information from the policy decision function network element, where the first policy information includes at least one of an access control rule of the network slice, a service processing parameter of the network slice, or a charging key value corresponding to the network slice;

and the strategy execution function network element executes first processing according to the first strategy information.

20. The method of claim 19, wherein the policy enforcement function network element sending a first request to a policy decision function network element comprises:

when the policy enforcement function network element configures the network slice, the policy enforcement function network element sends the first request to the policy decision function network element; alternatively, the first and second electrodes may be,

and under the condition that the access control of the network slice is determined to be set, the policy execution function network element sends the first request to the policy decision function network element.

21. The method of claim 19 or 20, wherein the policy enforcement function network element is a session management function network element, SMF, the method further comprising:

the policy execution function network element receives a session establishment request from a terminal device before sending the first request, wherein the session establishment request carries an identifier of the network slice;

the policy execution function network element executes a first process according to the first policy information, including:

the first policy information includes a service processing parameter of the network slice, and the policy enforcement function network element sets the service processing parameter of the session of the terminal device as the service processing parameter of the network slice; and/or the presence of a gas in the gas,

the first policy information includes a charging key corresponding to the network slice, and the policy execution function network element sets the charging key of the session of the terminal device as the charging key corresponding to the network slice.

22. The method according to claim 19 or 20, wherein the first policy information comprises access control rules for the network slice, the access control rules comprising allowance that the number of terminal devices located within a service area of the policy enforcement function network element and registered to the network slice exceeds a first terminal device number quota, the policy enforcement function network element comprising a network slice access control function network element NSACF;

when the number of terminal devices which are located in the service area of the policy enforcement function network element and registered to the network slice is greater than or equal to the first terminal device number quota, the policy enforcement function network element performs a first process according to the first policy information, including:

the strategy execution function network element stores the information of the terminal equipment to be registered or registered to the network slice; and/or the presence of a gas in the gas,

the policy enforcement function network element receives a first quota reservation application, where the first quota reservation application is used to request reservation of a registration quota of the network slice for the terminal device to be registered to the network slice.

23. The method of claim 22, wherein the first policy information further includes information indicative of a first threshold, and wherein the accepting, by the policy enforcement function network element, the first quota reservation application comprises:

the policy enforcement function network element determines that the difference between the number of terminal devices which are located in the service area of the policy enforcement function network element and registered to the network slice and the first terminal device number quota does not exceed the first threshold;

and the policy execution function network element receives the first quota reservation application.

24. The method of claim 19 or 20, wherein the first policy information includes access control rules for the network slice, the access control rules including a number of sessions established through the network slice within a service area of the policy enforcement function network element that includes an NSACF that performs a first process according to the first policy information, including:

when the number of sessions established through the network slice and located in the service area of the policy enforcement function network element is greater than or equal to the first session number quota, the policy enforcement function network element performs a first process according to the first policy information, including:

the strategy execution function network element stores the information of the session to be established or established through the network slice; and/or the presence of a gas in the gas,

and the policy execution function network element receives a second quota reservation application, wherein the second quota reservation application is used for requesting quota establishment for the session reservation session to be established through the network slice.

25. The method of claim 24, wherein the first policy information further includes an indication of a second threshold, and wherein the acceptance of the second quota reservation application by the policy enforcement function network element comprises:

the policy execution function network element determines that the difference between the number of sessions established through the network slice and the first session number quota, which are located in the service area of the policy execution function network element, does not exceed the second threshold;

and the policy execution function network element receives the second quota reservation application.

26. The method according to any of claims 19-25, wherein the policy enforcement function network element comprises an NSACF, the method further comprising:

when a first condition is met, the policy execution function network element sends first information to the policy decision function network element, wherein the first information is used for indicating that the first condition is met;

the first condition includes:

the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is reduced to a third threshold value; alternatively, the first and second electrodes may be,

the number of terminal devices which are located in the service area of the strategy execution function network element and register the network slice is increased to a fourth threshold value; alternatively, the first and second electrodes may be,

reducing the number of sessions which are located in the service area of the policy enforcement function network element and are established through the network slice to a fifth threshold; alternatively, the first and second electrodes may be,

the number of sessions located within the service area of the policy enforcement function network element and established through the network slice increases to a sixth threshold.

27. The method according to any of claims 19-26, wherein the policy enforcement function network element comprises an NSACF, the method further comprising:

when a second condition is met, the policy execution function network element sends second information to the policy decision function network element, wherein the second information is used for indicating the number of terminal devices which are located in a service area of the policy execution function network element and register the network slice;

the satisfying the second condition includes:

the sending time condition of the second information is met; and/or the presence of a gas in the atmosphere,

the policy execution function network element receives the request information of the second information from the policy decision function network element.

28. The method according to any of claims 19-27, wherein the policy enforcement function network element comprises an NSACF, the method further comprising:

when a third condition is met, the policy execution function network element sends third information to the policy decision function network element, where the third information is used to indicate the number of sessions that are located in a service area of the policy execution function network element and are established through the network slice;

the satisfying a third condition includes:

the sending time condition of the third information is met; and/or the presence of a gas in the atmosphere,

and the policy execution function network element receives request information of the third information from the policy decision function network element.

29. A communications apparatus, comprising: a processor and a memory; the memory for storing one or more computer programs, the one or more computer programs comprising computer executable instructions that, when executed by the communication apparatus, cause the communication apparatus to perform the method of any of claims 1-18 or cause the communication apparatus to perform the method of any of claims 19-28.

30. A computer-readable storage medium, for storing a computer program which, when run on a computer, causes the computer to perform the method of any one of claims 1-18, or causes the computer to perform the method of any one of claims 19-28.