WO2020015503A1

WO2020015503A1 - Method, device and system for selecting session management function network element

Info

Publication number: WO2020015503A1
Application number: PCT/CN2019/092894
Authority: WO
Inventors: 钱宏; 胡翔; 薛原; 陈曦
Original assignee: 华为技术有限公司
Priority date: 2018-07-17
Filing date: 2019-06-26
Publication date: 2020-01-23
Also published as: CN110730487B; CN110730487A

Abstract

A method, device and system for selecting a session management function network element, the method comprising: determining whether a user plane function network element that meets a screening condition exists, and if yes, sending first state information of a session management function network element to a network function storage library function network element, the first state information of the session management function network element being used to indicate that the session management function network element is available under the filtering condition, and the first state information also being used to select a session management function network element. Therefore, when subsequently selecting the session management function network element, the session management function network element may be selected according to the state thereof, and it may be ensured to the greatest extent possible that an available session management function network element may be selected so as to reduce the delay in creating a session process.

Description

Method, device and system for selecting session management function network element

This application claims the priority of a Chinese patent application filed on July 17, 2018 with the State Intellectual Property Office of China with the application number 201810783829.1 and the invention name "A Method, Device and System for Selecting a Network Element for Session Management Function", which The entire contents are incorporated herein by reference.

Technical field

The present application relates to the field of communication technologies, and in particular, to a method, a device, and a system for selecting a network element for a session management function.

Background technique

In the process of creating a packet data unit (PDU) session, the access and mobility management function (AMF) is used to select the session management function (SMF). Process, and the process of selecting a user plane function (UPF) by the SMF. When AMF selects SMF, it selects SMF that meets certain parameter requirements. For example, AMF can send certain parameter requirements to the network function repository function (NRF), and NRF selects the SMF that meets the parameter requirements, and Send the selection result to AMF.

Using the selection method in the prior art, there may be a situation: AMF selects an SMF, but when the SMF selects a UPF, it cannot select a UPF that meets certain parameter requirements, that is, for the SMF, there is no The available UPF, which means that the SMF selected by the AMF is invalid, causing the activation to fail.

It can be seen that this method of selecting SMF is relatively inefficient and brings a large delay to the process of creating a PDU session.

Summary of the invention

The embodiments of the present application provide a method, a device, and a system for selecting a network element for a session management function, which are used to improve the efficiency of selecting a network element for a session management function and reduce the delay in the process of creating a session.

In a first aspect, a first method for selecting a session management function network element is provided. The method is performed by, for example, a session management function network element. In a 5G system, the session management function network element is, for example, an SMF. The method includes: determining whether there is a user plane function network element that meets the screening condition, and if there is a user plane function network element that meets the screening condition, sending the first state information of the session management function network element to the network function repository function Network element, the first state information of the session management function network element is used to indicate that the session management function network element is available under the screening condition, and the first state information of the session management function network element is used to select the session management function network element.

In the embodiment of the present application, the state of the session management function network element is determined according to the situation of the user plane function network element. If there is a user plane function network element that meets the filtering conditions, the state of the session management function network element is in the screening. The condition is the available status, and the first status information indicating that the session management function network element is available under the screening condition is sent to the network function repository function network element, and then the network function repository function network element is subsequently in the screening condition. When selecting a session management function network element, it can be selected according to the state of the session management function network element. For example, only the session management function network element with the first state information can be selected, that is, only the ones that are available under the filter condition are selected. Session management function network element, so as far as possible is guaranteed, the selected session management function network element has available user plane function network elements, thereby reducing the number of user plane function network elements because the selected session management function network element is not available The probability of re-selection of the network element of the session management function is caused, which improves the efficiency of selecting the network element of the session management function. Rate, reducing the delay in the process of creating a session and also increasing the activation rate.

In a possible implementation manner, the first state information includes: information indicating that the session management function network element is available under the screening condition; or, indicating that the session management function network element has a user plane that meets the screening condition Information about the functional NEs.

That is to say, the first state information can have two indication modes. The first indication mode can be called an implicit indication mode, which indicates that the session management function network element is available, and the session management function network element is available under the filtering conditions. It means that the session management function network element has user plane function network elements available under the filter condition. Therefore, the implicit indication method is to indicate whether the session management function network element is available to indicate whether the session management function network element is available. User plane function network element. The second indication method can be called an explicit indication method, which indicates that the session management function network element has a user plane function network element that satisfies the filtering conditions, that is, the explicit indication method directly indicates whether the session management function network element has Available user plane function network elements. Through the implicit indication method, it can be determined that the session management function network element is available, and it can be determined that the session management function network element is available with the user plane function network element, and the double content can be determined by one instruction; and the explicit instruction can It is directly determined that the session management function network element has a user plane function network element available, and the indication method is more direct. As for which indication method is adopted for the first state information, it may be predefined by a protocol, or determined in advance through negotiation between network elements, and the like is not specifically limited.

In a possible implementation manner, determining whether there is a user plane function network element that meets the filtering conditions may include: obtaining information of at least one user plane function network element, and according to the obtained information of at least one user plane function network element, Determine whether there is a user plane function network element that meets the screening condition among the at least one user plane function network element; or, that no information of the user plane function network element is obtained, and determine that there is no user plane function network element that meets the screening condition .

Since it is necessary to determine whether there are user plane function network elements that meet the filtering conditions, all that can be thought of is to obtain the information of the user plane function network elements, and then determine whether these user plane function network elements meet the filter conditions based on the information of the user plane function network elements. . To obtain the information of the user plane functional network elements, it may or may not be available. Then, in the embodiment of the present application, if the information of the user plane function network element is obtained, it can be determined whether the user plane function network element meets the filtering condition according to the information of the user plane function network element, and if the user plane function network element is not obtained, Information, you can directly determine that there are no user plane function network elements that meet the filtering conditions. Therefore, regardless of whether the information of the user plane function network element can be obtained, the embodiments of the present application can determine whether there is a user plane function network element that meets the filtering conditions.

In a possible implementation manner, acquiring information of at least one user plane function network element may include: receiving information of the at least one user plane function network element from the at least one user plane function network element, where the information from one user The area function network element is information of a user area function network element; or, a subscription message is sent to the network function repository function network element, the subscription message is used to subscribe to the information of the user plane function network element that meets the filtering conditions, and receive A notification message from the network element of the network function storage function, and information of at least one user plane function element is obtained according to the notification message.

The user plane function network element information can be obtained in different ways. For example, it can directly interact with the user plane function network element to obtain the user plane function network element information. This method of acquisition is relatively straightforward. Alternatively, you can also initiate a subscription to the functional unit of the network function repository, and obtain the user plane function network element information through the subscription process. This way does not need to interact with too many user plane function network elements, which reduces the interaction process between devices. In addition, only one subscription is needed to continuously obtain the information of the user plane functional network elements, and the method is relatively simple.

In a possible implementation manner, the screening condition includes at least one of DNN and S-NSSAI.

For example, the screening conditions include DNN, or the screening conditions include S-NSSAI, or the screening conditions include DNN and S-NSSAI. Of course, the parameters included in the screening conditions are not limited to this. For example, the screening conditions may include other parameters in addition to at least one of DNN and S-NSSAI. For example, the screening conditions include S-NSSAI and other parameters, or the screening conditions. DNN and S-NSSAI may not be included, but other parameters may be included, which are not specifically limited.

In a possible implementation manner, if there is no user plane function network element that meets the screening condition, the second state information of the session management function network element is sent to the network function repository function network element. The second state information is used to indicate that the session management function network element is unavailable under the screening condition; or, if there is no user plane function network element that meets the screening condition, sending a delete instruction to the network function repository function network element, The deletion instruction is used to instruct the network function repository function network element to delete the information of the session management function network element from the information of the session management function network element available under the screening condition.

For example, the network element of the network function storage function stores state information of the network element of the session management function. For a network element of the session management function, the state information of the network element of the session management function includes the first state of the network element of the session management function. Information or second status information. Then, if there is no user plane function network element that meets the screening conditions, the second state information of the session management function network element may be sent to the network function repository function network element, so that the network function repository function network element can store both The first state information of the session management function network element can also store the second state information of the session management function network element, so that it is very clear what kind of state the session management function network element is. Alternatively, the network function repository function network element may store only the first state information of the session management function network element, that is, the session management function network element where the network function repository function network element stores the first state information is NEs with session management functions available under certain filtering conditions. Then, if the state information of the session management function network element is the second status information, a deletion instruction can be sent to the network function storage function network element, so that the network function storage function network element can delete the session management function network element. The information indicates that the session management function network element is no longer an available session management function network element. It can be seen that when the network element of the network function storage function is used to store the state of the network element of the session management function, different storage methods can be adopted, which is more flexible.

In a possible implementation manner, the screening condition is specifically the first screening condition. Then, determining whether there is a user plane function network element that meets the screening condition may include: determining whether there is a user plane function that meets the first screening condition. Network element; or the screening condition is specifically the second screening condition and the third screening condition, then determining whether there is a user plane functional network element that meets the screening condition may include determining whether there is a user plane that meets the second screening condition A functional network element, and determining whether there is a user plane functional network element that meets the third screening condition.

The selection criteria may be one or more. For example, if there is one kind of screening condition, and this filtering condition is called the first filtering condition, then it can be directly determined whether there are user plane functional network elements that meet the first filtering condition; or there are multiple filtering conditions, for example, including the second filtering condition and The third screening condition, then, can determine whether there is a user plane function network element that meets the screening condition for each screening condition, so as to avoid missing the screening condition.

In a possible implementation manner, if there is a user plane function network element that meets the screening condition, the first state information of the session management function network element is sent to a network function repository function network element, and the session management function network The first state information of the element is used to indicate that the session management function network element is available under the screening condition, and includes:

The screening condition is specifically a first screening condition. If there is a user plane function network element that meets the first screening condition, the first state information of the session management function network element is sent to the network function repository function network element, and the session management The first state information of the function network element is used to indicate that the session management function network element is available under the first screening condition;

or,

The screening condition is specifically a second screening condition and a third screening condition. If there is a user plane function network element that meets the second screening condition, the first state information of the session management function network element is sent to the network function repository function network. Element, the first state information of the session management function network element is used to indicate that the session management function network element is available under the second screening condition; or, if there is a user plane function network element that meets the third screening condition, the session management The first state information of the function network element is sent to the network function repository function network element, and the first state information of the session management function network element is used to indicate that the session management function network element is available under the third screening condition.

It can be seen that for each screening condition, there can be corresponding first state information. Even if a session management function network element is unavailable under certain screening conditions, it is likely to be available under other screening conditions, thus a session management function. Network elements can exhibit a variety of characteristics and are more practical. Of course, if the first state information of the session management function network element under the second screening condition and the first state information under the third screening condition are to be sent to the network function repository function network element, then two first Status information, or only one piece of first status information can be sent, and this first status information can be used as the first status information of the session management function network element under the second screening condition and the session management function network element in the third The first state information under the filter condition.

In a possible implementation manner, when the screening condition is specifically the first screening condition, if the first screening condition is empty, it means that the first screening condition is used to screen all user plane function network elements; or In the case where the screening condition is specifically the second screening condition and the third screening condition, if at least one of the second screening condition and the third screening condition is empty, it means that the at least one screening condition is used for Filter all user plane function network elements.

A filter condition may correspond to at least one parameter, or may not correspond to any parameter, that is, the filter condition is empty. Then, the embodiment of the present application considers that if a screening condition is empty, it indicates that the screening condition is used to screen all user plane function network elements. Of course, all the user plane function network elements selected here should be the normal user plane function network elements.

In a possible implementation manner, the first state information of the session management function network element includes parameter information corresponding to the screening condition, and includes an instruction for indicating that the session management function network element is available under the screening condition. Information; or, the first state information of the session management function network element includes identification information of the screening condition, and includes indication information for indicating that the session management function network element is available under the screening condition.

The parameter information corresponding to the screening condition can characterize the corresponding screening condition, so the first state information can directly include the parameter information corresponding to the screening condition, so that the corresponding screening condition can be determined more directly. Alternatively, it is also possible to set identification information for the filtering conditions. For example, if one type of identification information is a number, the corresponding filtering conditions can be determined through the identification information. It is relatively simple, and the amount of data of the identification information of the filtering conditions is generally smaller than that of the parameter information. The amount of data, thereby helping to reduce the amount of data of the first state information.

In a second aspect, a second method for selecting a session management function network element is provided. The method may be executed by a network function repository function network element. In a 5G system, the network function repository function network element is, for example, NRF. The method includes: receiving a request message from a mobility management function network element, where the request message is used to request information of a session management function network element that meets a fourth screening condition, and is determined according to status information of at least one session management function network element Whether there are available session management function network elements that satisfy the fourth screening condition, and the status information of at least one session management function network element is used to indicate whether at least one session management function network element is in an available state under the fourth screening condition. The mobility management function network element sends a screening result.

When selecting a session management function network element, it can be selected according to the status information of the session management function network element. The status information of the session management function network element is used to indicate whether the session management function network element is available under the fourth screening condition. Wherein, the session management function network element is available under the fourth screening condition, which may mean that the session management function network element has a user plane function network element that meets the fourth screening condition. Therefore, selecting the session management function network element according to the state information of the session management function network element can ensure that the selected session management function network element has available user plane function network elements, so that the subsequent process of creating sessions can be performed sequentially. The selection of the session management function network element will not fail because the selected session management function network element has no user plane function network element available, which improves the efficiency of selecting the session management function network element and reduces the process of creating sessions. The delay also increases the activation rate.

In a possible implementation manner, the status information of a session management function network element includes: information indicating that a session management function network element is an available session management function network element that meets a fourth screening condition, or indicates a session management function The network element is information of an unavailable session management function network element that meets the fourth screening condition; or, information indicating that a session management function network element has a user plane function network element that meets the fourth screening condition, or indicates a session management function The network element does not have information of a user plane function network element that meets the fourth screening condition.

When introducing the implementation method of the first aspect, it was introduced that the first state information of the session management function network element may have two indication modes: implicit indication mode and explicit indication mode. Then, by the same token, the state of the session management function network element Information also has two indication modes: implicit indication mode and explicit indication mode. Which indication method is specifically selected may be predefined through a protocol or determined through negotiation between network elements.

In a possible implementation manner, the filtering result is specifically information of K session management function network elements, where the information of the K session management function network elements is used to indicate that the K session management function network elements meet the screening condition. Available session management function network element; or, the filtering information is specifically a failure indication, where the failure indication indicates that the available session management function network element that does not satisfy the fourth screening condition.

After the selection is completed, an available session management function network element that meets the fourth filter condition may be selected, or an available session management function network element that meets the fourth filter condition may not be selected. Then, if an available session management function network element that meets the fourth screening condition is selected, the information of the selected available session management function network element that meets the fourth screening condition can be directly sent to the mobility management function as the screening condition. Network element, and if an available session management function network element that meets the fourth screening condition is not selected, a failure indication may also be sent to the mobility management function network element, so whether or not an available one that meets the fourth screening condition can be selected Both the session management function network element and the mobility management function network element can clarify the corresponding screening results.

In a possible implementation manner, the state information of the at least one session management function network element is from at least one session management function network element.

That is, the session management function network element can determine the status information of the session management function network element and send the status information of the session management function network element to the network function repository function network element, so that the network function repository function network element Select based on the state information of the session management function NE. Among them, a session management function network element generally can only determine the status information of the session management function network element. Therefore, the network function repository function network element may interact with at least one session management function network element to obtain at least one session. Status information of management function NEs.

In a possible implementation manner, the state information of a session management function network element among the at least one session management function network element includes parameter information corresponding to at least one screening condition, and includes information used to indicate a session management function network element. Indication information about whether an element is available under each of the at least one screening condition, and the at least one screening condition includes a fourth screening condition; or, one of the at least one session management function network element of the session management function network element The status information includes identification information of at least one screening condition, and includes indication information for indicating whether a session management function network element is available under each of the at least one screening condition. The at least one screening condition includes Fourth screening condition.

The parameter information corresponding to the screening condition can characterize the corresponding screening condition, so the first state information can directly include the parameter information corresponding to the screening condition, so that the corresponding screening condition can be determined more directly. Alternatively, it is also possible to set identification information for the filtering conditions. For example, if one type of identification information is a number, the corresponding filtering conditions can be determined through the identification information. It is relatively simple, and the amount of data of the identification information of the filtering conditions is generally smaller than that of the parameter information. The amount of data, thereby helping to reduce the amount of data of the first state information. Moreover, the state information of a session management function network element may include information corresponding to at least one filtering condition, so that a session management function network element may reflect one or more characteristics.

According to a third aspect, a system for selecting a session management function network element is provided. The system may include a session management function network element and a network function repository function network element. The session management function network element is used to determine whether there is a user plane function network element that meets the screening conditions. If there is a user plane function network element that meets the screening conditions, the first state information of the session management function network element is sent. To the network function repository function network element, the first state information of the session management function network element is used to indicate that the management function network element is available under the screening condition, and the first state information is used to select the session management function network element; network A functional network element of the functional repository is configured to receive the first status information.

For the technical effect brought by the third aspect or the possible implementation manner of the third aspect, refer to the technical effect brought by the first aspect or different implementation manners of the first aspect, which is not described in detail here.

In a possible implementation manner, the network function repository function network element is further configured to:

Receive a request message from a mobility management function network element, the request message is used to request information about a session management function network element that meets the fourth screening condition, where a session management function network element that meets the fourth screening condition refers to the The session management function network element has a user plane function network element that meets the fourth screening condition; and determines whether there is an available session management function network element that meets the fourth screening condition based on the status information of at least one session management function network element. The state information of a session management function network element is used to indicate whether at least one session management function network element is in an available state under a fourth screening condition; and sending a screening result to the mobility management function network element.

The system for selecting a network element for a session management function provided in the third aspect may further include a network element for a mobility management function, and of course, it may not include a network element for a mobility management function, which is not specifically limited.

For the technical effect brought by the possible implementation manner of the third aspect, refer to the technical effect brought by the second aspect, which is not described in detail here.

In a fourth aspect, the present application provides a device, which may be a session management function network element or a network function repository function network element, or a chip. The device has a function of implementing the embodiments of any one of the first aspect, the second aspect, or the third aspect described above. This function can be realized by hardware, and can also be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

According to a fifth aspect, an apparatus is provided, including: a processor and a memory; the memory is configured to store a computer execution instruction, and when the apparatus is running, the processor executes the computer execution instruction stored in the memory, so that the apparatus executes The method for selecting a session management function network element according to the above first aspect or any one of the first aspects, or to cause the apparatus to execute the session selection function network according to the second aspect or any of the second aspects above. Or a method for selecting the session management function network element according to the third aspect or any one of the third aspects.

According to a sixth aspect, the present application further provides a computer-readable storage medium, where the computer-readable storage medium stores instructions that, when run on a computer, cause the computer to execute the methods described in the above aspects.

In a seventh aspect, the present application further provides a computer program product including instructions, which when executed on a computer, causes the computer to execute the methods described in the above aspects.

In the embodiment of the present application, when selecting the network element of the session management function, the network element of the network function repository function may select the network element of the session management function, which improves the efficiency of selecting the network element of the session management function and reduces the efficiency. The delay in the process of creating a session also increases the activation rate.

These or other aspects of the present application will be more concise and easy to understand in the description of the following embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a schematic diagram of a system for selecting a network element for a session management function according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a network architecture of a non-roaming scenario applied in an embodiment of the present application; FIG.

3 is a schematic diagram of a network architecture of a local offload roaming scenario applied in an embodiment of the present application;

4 is a schematic diagram of a network architecture of a home routing roaming scenario applied to an embodiment of the present application;

FIG. 5 is a process of selecting SMF by AMF in the process of creating a PDU session;

Figure 6 shows the process by which the SMF selects the UPF in the process of creating a PDU session;

7 is a flowchart of a method for selecting an SMF according to an embodiment of the present application;

8 is a flowchart of another method for selecting SMF according to an embodiment of the present application;

FIG. 9 is a flowchart of still another method for selecting SMF according to an embodiment of the present application; FIG.

10 is a schematic diagram of a device according to an embodiment of the present application;

FIG. 11 is a schematic diagram of another device according to an embodiment of the present application.

detailed description

In order to make the objectives, 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.

In the following, some terms in the embodiments of the present application are explained so as to facilitate understanding by those skilled in the art.

1) A network element, or a network device, includes, for example, an access network network element, or an access network device, such as a base station (for example, an access point) and a user plane function network element.

The base station may refer to a device in an access network that communicates with a wireless terminal device through one or more cells on an air interface. The network element can be used to convert the received air frames and Internet Protocol (IP) packets into each other, and serve as a router between the terminal device and the rest of the access network, where the rest of the access network can include an IP network. The network element can also coordinate the attribute management of the air interface. For example, the network element may include an evolved base station (NodeB or eNB or e-NodeB, evolutional NodeB) in a long term evolution (LTE) system or an evolved LTE system (LTE-Advanced, LTE-A), or It can also include the next generation node B (gNB) in the fifth generation (5G) new radio (NR) system, or it can also include the cloud access network (cloud radio access A centralized unit (CU) and a distributed unit (DU) in a network (CloudRAN) system are not limited in the embodiments of the present application.

User plane functional network elements include, for example, a serving gateway (SGW) and a packet data network gateway (PDN-GW) in a fourth-generation mobile communication technology (4G) system. In a 5G system, for example, UPF is mainly responsible for connecting to external networks. It can be considered that the UPF in the 5G system is equivalent to the combination of the SGW and the PDN-GW in the 4G LTE system.

In the embodiment of the present application, the network element further includes a core network element, or a core network device. In a fourth generation mobile communication technology (4G) system, the core network device includes, for example, a mobility management entity (MME). ), Etc. In a 5G system, the core network equipment includes, for example, a policy control function (PCF), NRF, AMF, or SMF. It can be considered that after the evolution from 4G to 5G, the functions of the MME are separated into AMF and SMF, where AMF is used to manage the mobile context of the user, and SMF is used to manage the session context.

2) The terms "system" and "network" in the embodiments of the present application can be used interchangeably. "Multiple" means two or more. In view of this, in the embodiments of the present application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, such as one, two or more. For example, including at least one means including one, two, or more, and without limiting which ones are included, for example, including at least one of A, B, and C, then including A, B, C, A and B, A and C, B and C, or A and B and C. In the same way, the understanding of the description of "at least one" is similar. "And / or" describes the association relationship of the associated objects, and indicates that there can be three kinds of relationships, for example, A and / or B can mean: there are three cases where A exists alone, A and B exist simultaneously, or B exists alone. In addition, the character "/", unless otherwise specified, generally indicates that the related objects are an "or" relationship.

In addition, in order to facilitate a clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as “first” and “second” are used to distinguish between the same or similar items having substantially the same functions and functions. Those skilled in the art can understand that the words "first" and "second" do not limit the order, timing, priority, or importance, and the words "first" and "second" are not necessarily different. . For example, the "first screening condition" and the "second screening condition" described in the embodiments of the present application may be the same screening condition or different screening conditions, which are not specifically limited in the embodiments of the present application.

It should be noted that the session management function network element, network function repository function network element, mobility management function network element, and user plane function network element, etc., as well as further SMF, NRF, AMF, and UPF involved in the embodiments of the present application. Etc. is just a name, and the name does not constitute a limitation on the device itself. In 5G systems and other communication systems in the future, session management function network elements, network function repository function network elements, mobility management function network elements, and user plane function network elements, as well as further SMF, NRF, AMF, and UPF, etc. , May also be other names, which are not specifically limited in the embodiment of the present application. For example, UPF may also be replaced with UP, etc., which are described here in a unified manner, and will not be described in detail below.

First, an embodiment of the present application provides a system 100 for selecting a session management function network element. As shown in FIG. 1, the system 100 may include a session management function network element 101 and a network function repository function network element 102. In Figure 1, the connection between the session management function network element 101 and the network function repository function network element 102 indicates that the two network elements can communicate. The two network elements can be connected by wire or wirelessly. .

The session management function network element 101 may be used to determine whether there is a user plane function network element that meets the screening conditions. If there is a user plane function network element that meets the screening conditions, the first state information of the session management function network element 101 is sent. The first state information to the network function repository function network element 102 and the session management function network element 101 is used to indicate that the session management function network element 101 is available under the screening condition, and the first state information is used to select the session management function. Network element 101;

The network function repository function network element 102 is configured to receive the first status information.

To select a user plane function network element for the session management function network element 101, it is necessary to select a user plane function network element that meets certain parameter requirements. In the embodiment of the present application, the parameter requirements that need to be satisfied are referred to as a filtering condition. Among them, the session management When the functional network element 101 selects a user-plane functional network element, it may be selected according to one kind of filtering condition or may be selected based on multiple filtering conditions. That is, the number of filtering conditions may be one or multiple. No restrictions. Among them, the session management function network element 101 can obtain the information of the user plane function network element, and determine whether there is information of the user plane function network element that meets the screening conditions. If the information of the user plane function network element meets the screening condition, it indicates that the The user plane function network element to which the information of the user plane function network element belongs meets the filtering condition. If there are user plane function network elements that meet the screening conditions, the session management function network element 101 may send the first state information of the session management function network element 101 to the network function repository function network element 102. Of course, if there are User plane function network element, the session management function network element 101 may also first determine that the session management function network element 101 is available under the filtering conditions, and then send the first state of the session management function network element 101 to the network function repository function network element 102 information. In addition, if there is a user plane function network element that meets the filtering conditions, the session management function network element 101 can also set the state of the session management function network element 101 to be available under the filtering conditions.

Herein, the status information used to indicate that the session management function network element 101 is available is referred to as the first status information of the session management function network element 101. That is, although the session management function network element 101 determines whether there are user plane function network elements that meet the filtering conditions, there may be user plane function network elements that meet the screening conditions, or there may be no user plane function network elements that meet the screening conditions. That is, the state of the session management function network element 101 under the screening conditions may be available or unavailable. However, in the embodiment of the present application, the session management function network element 101 may only use the session management function network element. The first state information of 101 is sent to the network function repository function network element 102. After the network function repository function network element 102 receives the first state information, it can know which session management function network element 101 is available under the screening conditions.

In the embodiment of the present application, the first state information may have different implementation manners, and different implementation manners may implement different indication manners.

For example, the first state information includes information for indicating that the session management function network element 101 is available under the screening condition, and such an indication manner of the first state information may be considered as an implicit indication manner. That is, although the first state information directly indicates that the session management function network element 101 is available under the screening condition, it implicitly indicates that the session management function network element 101 has a user plane function network element that satisfies the screening condition. That is, whether the session management function network element 101 has a user plane function network element available is indicated by indicating the status of the session management function network element 101.

For another example, the first state information includes information used to indicate that the session management function network element 101 has a user plane function network element that meets the screening condition, and such an indication manner of the first state information may be considered as an explicit indication manner. That is, the first state information directly indicates whether the session management function network element 101 has a user plane function network element that satisfies the screening condition, which is relatively simple and straightforward.

As for the indication method of the first state information, it may be predefined by the protocol, or may be determined through negotiation between the network elements, and the like is not specifically limited.

When the mobility management function network element needs to obtain the information of the session management function network element 101 that satisfies the corresponding screening conditions, the mobility management function network element can send a request message to the network function repository function network element 102, and the network function repository The function network element 102 receives a request message from the mobility management function network element, for example, the request message is used to request information of the session management function network element 101 that meets the fourth screening condition, where the session management function that meets the fourth screening condition The network element 101 refers to a session management function network element 101 having a user plane function network element that meets a fourth screening condition, that is, a session management function network element 101 is available under the fourth screening condition.

According to the foregoing introduction, the session management function network element 101 sends the first state information of the session management function network element 101 to the network function repository function network element 102. Therefore, the network function repository function network element 102 may The state information of the session management function network element 101 determines whether there is an available session management function network element 101 that meets a fourth screening condition, wherein the state information of at least one session management function network element 101 is used to indicate at least one session management function network Whether element 101 is available under the fourth screening condition. The state information of the session management function network element 101 here may include first state information of the session management function network element 101.

The network function repository function network element 102 may send a screening result to the mobility management function network element after the screening is completed, where the screening result may indicate whether there is an available session management function network element 101 that meets the fourth screening condition.

As an optional manner, the system 100 for selecting a session management function network element provided in the embodiment of the present application may further include a mobility management function network element, which is not shown in the figure. If the system 100 further includes a mobility management function network element, the mobility management function network element can communicate with both the session management function network element 101 and the network function repository function network element 102.

It can be seen that in the embodiment of the present application, the state of the session management function network element 101 is determined according to the situation of the user plane function network element. If there is a user plane function network element that meets the filtering conditions, the session management function network element 101 The status of is the available status under the screening condition, and the session management function network element 101 may send the first status information indicating that the session management function network element 101 is available under the screening condition to the network function repository function network element 102 Then, when the network function repository function network element 102 subsequently selects the session management function network element 101 under the filtering condition, it may select according to the state of the session management function network element 101. For example, it may only select the first state information Session management function network element 101, that is, only the session management function network element 101 that is available under the filter condition is selected, so as to ensure that the selected session management function network element 101 has available user plane function network elements, The effective selection rate of the session management function network element 101 is improved.

In addition, if the mobility management function network element selects an unavailable session management function network element 101 in the manner in the prior art, the mobility management function network element needs to re-initiate the process of selecting the session management function network element 101 , The session management function network element 101 is reselected, and the solution provided in the embodiment of the present application is adopted, which reduces the need to reselect the session management function caused by the fact that the selected session management function network element 101 has no available user plane function network element. The probability of the network element 101 improves the efficiency of selecting the network element 101 for the session management function, reduces the delay in the process of creating a session, and increases the activation rate. The session here is, for example, a PDU session, or may be another session. As long as the session involving the mobility management function network element needs to select the session management function network element 101, it is within the protection scope of the embodiment of the present application, hereinafter Take PDU session as an example.

The embodiment shown in FIG. 1 introduces a system 100 for selecting a session management function network element provided by an embodiment of the present application. The following uses the system 100 as a 5G system as an example to introduce a possible application of the system 100 in a 5G system. Network architecture, or the application scenario of the system 100 in a 5G system. Scenarios in which the system 100 provided in the embodiment of the present application can be applied in a 5G system include, but are not limited to, a non-roaming scenario, a local offload roaming scenario, and a home routing roaming scenario. These scenarios are described below respectively.

Please refer to FIG. 2 for a schematic diagram of a network architecture in a non-roaming scenario. In this network architecture, the network slice selection function (NSSF), network opening function (NEF), NRF, policy control function (PCF), and unified data management , UDM), application functions (AF), authentication service functions (AUSF), AMF and SMF, these two network elements can communicate with each other based on the service method, of course, among them For two network elements to communicate, one network element needs to have a corresponding service method open to the other network element. In Figure 2, Nnssf can be regarded as the service interface of NSSF. Similarly, Nnef is the service interface of NEF, Npcf is the service interface of PCF, Nudm is the service interface of UDM, Naf is the service interface of AF, and Nausf is the service interface of AUSF. , Namf is the service interface of AMF, and Nsmf is the service interface of SMF. In addition, AMF and terminal equipment can communicate through the N1 interface, AMF and (R) AN can communicate through the N2 interface, SMF and UPF can communicate through the N4 interface, and terminal equipment communicates with the (R) AN through the air interface, (R) AN Can communicate with UPF through N3 interface, and UPF can communicate with data network (DN) through N6 interface.

For example, the session management function network element 101 provided in the embodiment of the present application may be implemented by SMF in the network architecture shown in FIG. 2, and the network function repository function network element 102 provided in the embodiment of the present application may be performed by FIG. 2 The implementation of NRF in the network architecture shown, and the mobility management function network element provided in the embodiment of the present application can be implemented by the AMF in the network architecture shown in FIG. 2. The user plane function network element involved in the embodiment of the present application , Can be realized by the UPF in the network architecture shown in FIG. 2. To make it easier to understand, some functional network elements mainly involved in the embodiments of the present application are briefly introduced below.

The mobility management function network element is, for example, an MME in a 4G system and an AMF in a 5G system. The embodiments of the present application are not limited thereto, and may also be implemented by other network elements in other communication systems. Taking the mobility management function network element as AMF as an example, the AMF is mainly responsible for interfacing with the wireless and terminating the radio access network (RAN) control plane (CP) interface, that is, the N2 interface, terminating the non-access Layer (non-access-stratum (NAS)) and NAS encryption and integrity protection, registration management, connection management, reachability management, mobility management, transfer session management (session) between user equipment (UE) and SMF management (SM) message, or UE's mobility event notification.

The session management function network element, such as the session management function network element 101, is a SMF in a 5G system, and may also be implemented by other network elements in other communication systems. Taking the session management function network element as an example, the SMF can provide session management functions such as session establishment, modification, and release, including the maintenance function of the tunnel between the UPF and access network (AN) nodes, and the UE's Internet protocol (internet). protocol (IP) address allocation and management, dynamic host control protocol (DHCP), selection and control of user plane (UP) functions, configuration of UPF diversion function, termination policy control function interface, accounting, Roaming, or policy control related functions.

User plane function network elements, such as UPF in 5G systems, can also be implemented by other network elements in other communication systems. Take the user plane function network element as UPF as an example. UPF is the user plane data forwarding entity. As an external PDU session point for data network interconnection, it has message routing and forwarding, message detection, user plane policy enforcement, legal monitoring, Functions such as traffic usage reports or quality of service (QoS) processing.

The network function repository function network element, for example, the network function repository function network element 102, in a 5G system, such as NRF, may also be implemented by other network elements in other communication systems. Taking the network function repository function network element as the NRF as an example, the NRF can support the service discovery function and maintain the NF configuration of available network function (NF) instances. In the roaming scenario, it is divided into a visiting NRF (visit NRF, vNRF) and a home NRF (home NRF, hNRF). Based on network implementation, it is divided into public land mobile network (PLMN) level NRF, shared slice NRF, or specific slice NRF. Among them, PLMN-level NRF can be understood as different PLMNs can use different NRFs; shared slice NRF can be understood as different network slices can share one NRF; specific slice NRF can be understood as different network slices respectively Use different NRF.

In addition, the concept of service method was mentioned in the introduction of the network architecture shown in Figure 2. Specifically, in the 5G system, it is currently considered that the network elements on the control plane can interact through a service-based method. Elements can interact with each other based on a point-to-point method. For example, in a 5G system, as a network element of the control plane, some service methods can be opened, and other devices can interact with the NRF through these service methods. Refer to Table 1 for some service methods open for NRF:

Table 1

Among them, the SMSF in Table 1 is a short message service function (SMSF), wherein the SMS is a short message service (short message service), and the BSF is a binding support function (BSF).

According to Table 1, NRF has opened all the service methods in Table 1 to AMF and SMF, and opened NF register method, NF update method and NF deregister method in NF management service to UPF. Then, UPF can send registration to NRF , Update, or cancel service requests associated with UPF.

For example, in the network architecture shown in Figure 2, according to Table 1, it can be seen that NRF opened the NF status notification service method to AMF, SMF, PCF, NEF, NSSF, SMSF, and AUSF. Then AMF, SMF, PCF, NEF, NSSF , SMSF, and AUSF can communicate with NRF through the NF status notification service method, but because NRF does not open the NF status notification service method to UDM, UDM cannot communicate with NRF through the NF status notification service method.

Please refer to FIG. 3, which is a schematic diagram of a network architecture for a local offload roaming scenario. In this network architecture, terminal equipment roams, so it includes two areas: VPLMN and HPLMN. In VPLMN, NSSF, NEF, NRF, PCF, AF, AMF, SMF and visited security edge protection proxy (vSEPP), these two network elements can communicate with each other based on the service method Of course, for two of the network elements to communicate, one network element needs to open the corresponding service method to the other network element, not many examples. In addition, AMF and terminal equipment can communicate through N1 interface, AMF and (R) AN can communicate through N2 interface, SMF and UPF can communicate through N4 interface, and terminal equipment can communicate with (R) AN, (R) AN Can communicate with UPF through N3 interface, UPF and DN can communicate through N6 interface. In HPLMN, UDM, NRF, PCF, AUSF, NEF and home security edge protection proxy (hSEPP), these two network elements can communicate with each other based on services, of course, among them For two network elements to communicate, one network element needs to open the corresponding service method to the other network element, not many examples. vSEPP and hSEPP can communicate through the N32 interface.

For example, the session management function network element 101 provided in the embodiment of the present application may be implemented by the SMF located in the VPLMN in the network architecture shown in FIG. 3. The network function repository function network element 102 provided in the embodiment of the present application may be Through the implementation of the NRF located in the VPLMN in the network architecture shown in FIG. 3, the mobility management function network element provided in the embodiment of the present application can be implemented by the AMF located in the VPLMN in the network architecture shown in FIG. The user plane function network element involved in the example can be implemented by the UPF located in the VPLMN in the network architecture shown in FIG. 3. Of course, the embodiments of the present application are not limited. In addition to the technical solutions provided in the embodiments of the present application, in addition to the VPLMN, they can also be applied to the HPLMN, that is, each network element provided in the embodiment of the present application can also be Corresponding network element located in HPLMN.

Please refer to FIG. 4 for a schematic diagram of the network architecture of the home routing roaming scenario. In this network architecture, terminal equipment also roams, so it also includes two areas, VPLMN and HPLMN. In VPLMN, NSSF, NEF, NRF, PCF, AMF, SMF, and vSEPP, these two network elements can communicate with each other based on the service method. Of course, two network elements need a network to communicate. The element has opened the corresponding service method to another network element, not many examples. In addition, AMF and terminal equipment can communicate through N1 interface, AMF and (R) AN can communicate through N2 interface, SMF and UPF can communicate through N4 interface, and terminal equipment can communicate with (R) AN, (R) AN Can communicate with UPF through N3 interface, UPF and DN can communicate through N6 interface. In HPLMN, UDM, NRF, NSSF, SMF, AF, PCF, AUSF, NEF and hSEPP, these two network elements can communicate with each other based on the service method. Of course, two of these network elements need to communicate. , Need one network element to open the corresponding service method to another network element, not many examples. In addition, SMF can communicate with UPF through N4 interface, UPF and DN can communicate through N6 interface, UPF in VPLMN and UPF in HPLMN can communicate through N9 interface, and vSEPP and hSEPP can communicate through N32 interface.

For example, the session management function network element 101 provided in the embodiment of the present application may be implemented by the SMF located in the VPLMN in the network architecture shown in FIG. 4, and the network function repository function network element 102 provided in the embodiment of the present application may be Through the implementation of the NRF located in the VPLMN in the network architecture shown in FIG. 4, the mobility management function network element provided in the embodiment of the present application can be implemented by the AMF located in the VPLMN in the network architecture shown in FIG. 4, and this application is implemented. The user plane function network element involved in the example can be implemented by the UPF located in the VPLMN in the network architecture shown in FIG. 4. Of course, the embodiments of the present application are not limited. In addition to the technical solutions provided in the embodiments of the present application, in addition to the VPLMN, they can also be applied to the HPLMN, that is, each network element provided in the embodiment of the present application can also be Corresponding network element located in HPLMN.

The network architecture shown in FIG. 3 and the related network elements in the network architecture shown in FIG. 4 have already been introduced after the network architecture shown in FIG. 2 has been introduced, so they are not described in detail.

In Figures 2 to 4, the main function of the (R) AN is to control the terminal device to access the mobile communication network through wireless access. (R) AN is part of a mobile communication system. It implements a wireless access technology. (R) AN equipment includes but is not limited to: gNB, eNB, radio network controller (RNC), node B (NB), base station controller (BSC), base station in 5G Transceiver station (BTS), home base station (e.g., home nodeB, or home nodeB, HNB), baseband unit (BBU), transmission point (receiving point, TRP), and transmission point (TRP) transmitting point (TP), mobile switching center, etc. In addition, it can also include wireless fidelity (wifi) access points (AP) and the like.

The foregoing introduces a system 100 for selecting a session management function network element provided by the embodiment of the present application, and several network architectures in which the system 100 may be applied in a 5G system. The following takes the 5G system as an example to introduce the implementation of the present application. Case technical background.

The process of creating a PDU session includes the process of selecting the SMF by the AMF and the process of selecting the UPF by the SMF. In the 3rd Generation Partnership Project (3GPP) standard 23.502-f10 version, the process of selecting SMF and selecting UPF in the existing 5G system architecture is introduced in detail. First introduce the process of AMF selecting SMF, please refer to Figure 5.

S501. The AMF sends a request message to the NSSF. For example, the first request message is received by the NSSF. The NSSF receives the first request message, and the first request message carries request parameters. The request parameters include network slice selection support information that meets the request of the terminal device. assistance (information, NSSAI) conditions (single network selection, S-NSSAI), PLMN identification number (ID), and indicate whether the first request message is applicable to a non-roaming scenario or a local offload roaming scenario.

For example, the AMF may call a network slice selection acquisition (Nnssf_NSSelection_Get) service method provided by the NSSF, and send a first request message to the NSSF.

S502. The NSSF selects a network slice according to the request parameters sent by the AMF. That is, the NSSF selects a network slice that meets the request parameters sent by the AMF. After that, the NSSF determines and sends the NRF information suitable for the network slice to the AMF. For example, the NSSF is Call the response (Nnssf_NSSelection_Get response) service method provided by the NSSF to obtain the network slice selection response to the AMF. For example, the message sent by the NSSF to the AMF is called the first response message, which is the first response message in Figure 5. A response message. The network slice instance (NSI) ID of the network slice selected by the NSSF may be sent as an option.

S503. The AMF sends a second request message to the NRF, and the NRF receives the second request message. The second request message is used to query the SMF that meets the parameter requirements, and the AMF is used to query the parameters of the SMF, that is, the parameters carried in the second request message, such as S-NSSAI, PLMN ID, and DNN.

For example, the AMF may call a NF discovery request (Nnrf_NFDiscovery_Request) service method provided by the NRF to send a second request message to the NRF.

S504. The NRF sends the fully-qualified domain name (FQDN) or IP address of the SMF to the AMF. For example, the NRF sends the FQDN or IP address to the AMF by calling the service response (Nnrf_NFDiscovery_Request response) provided by the NRF. The FQDN or IP address of the receiving SMF. This is equivalent to the AMF obtaining the requested SMF information.

Of course, if the AMF knows the information of the NRF, S501 and S502 in the process shown in FIG. 5 may not be executed, and only S503 and S504 need to be executed; otherwise, S501 to S504 need to be executed.

The flow shown in Figure 5 introduces the process of AMF selecting SMF. The following describes the flow of SMF selecting UPF. The following describes the process of SMF selecting UPF through NRF. Please refer to Figure 6.

FIG. 6 includes two processes, one is a process in which the SMF subscribes to the UPF information to the NRF, and the other is a process in which the UPF sends the UPF information to the NRF.

The process of the SMF subscribing to the UPF information from the NRF includes the following S601 and S602:

S601. The SMF sends a subscription request to the NRF, and the NRF receives the subscription request. The subscription request carries subscription parameters. The subscription parameters are information about the UPF that the SMF is interested in, that is, information about the UPF that the SMF needs to subscribe to. The subscription parameters include, for example, a data network name (DNN), S-NSSAI, or SMF area identity (SMF).

For example, the SMF may call the NF management NF status subscription (Nnrf_NFManagement_NFStatusSubscribe) service method provided by the NRF to initiate a subscription to the NRF, that is, send a subscription request.

S602. The NRF sends a notification message to the SMF, and the SMF receives the notification message, and the notification message carries information about the UPF that currently meets the subscription parameters. In FIG. 6, the notification message in S602 is referred to as a first notification message.

For example, the NRF may call the NF management NF status notification (Nnrf_NFManagement_NFStatusNotify) service method provided by the NRF to send a notification message to the SMF.

For example, the UPF information carried in the first notification message may be the FQDN or IP address of the N4 interface of the UPF.

Among them, if there is currently no UPF that meets the subscription parameters, the NRF may not need to execute S602; or, the NRF executes S602, but in S602, the first notification message sent by the NRF to the SMF does not carry UPF information that meets the subscription parameters, Instead, it carries notification information, which is used to notify the SMF that there is currently no UPF that meets the subscription parameters.

The process by which the UPF sends UPF information to the NRF includes the following S603-S607. Among them, the following S603-S607 can also be understood as introducing the process that occurs after a new UPF is deployed to the system:

S603. A new UPF is deployed to the system.

S604. The operation, administration, and maintenance (OAM) system configures identification information of the NRF on the UPF, and configures attribute information for the UPF.

S605. The UPF sends a request message to the NRF, such as a third request message. The NRF receives the third request message, and the third request message carries the network function (NF) type of the UPF, the FQDN, or the IP of the N4 interface. Address, and attribute information configured by the OAM for the UPF in S604.

For example, the UPF may call the NF management NF registration (Nnrf_NFManagement_NFRegister) service method provided by the NRF to send a request message to the NRF.

S606. The OAM system registers the UPF information with the NRF.

For example, when a UPF is deployed to the system or is logged out of the system, the OAM system can write the information of the deployed or unregistered UPF into the local configuration of the SMF. SMF can choose UPF based on this information. In addition, the UPF information written in the local configuration of the SMF can also be updated. For example, at any time after the initial configuration, the UPF information on the SMF can be updated through the OAM system.

S606 is an equivalent method of S605, and one of the two methods can be selected, that is, S605 and S606 can be selected and executed.

S607. If the information of the UPF meets the subscription parameters of the SMF, that is, the UPF meets the subscription request of the SMF, the NRF can send a notification message to the SMF, and the SMF receives the notification message, and the notification message carries the information of the UPF. For example, the UPF information carried in the notification message may be the FQDN or IP address of the N4 interface of the UPF. In FIG. 6, the notification message in S607 is called a second notification message.

For example, the NRF may call the Nnrf_NFManagement_NFStatusNotify service method to send a second notification message to the SMF.

According to the process shown in Figure 5, the AMF may select multiple SMFs. According to the process shown in Figure 6, the SMF may select multiple UPFs. When creating a PDU session, the AMF may select one SMF from multiple SMFs to perform this process. If the SMF has multiple optional UPFs, the SMF can also select a UPF from multiple UPFs to perform the current PDU session.

According to the process shown in FIG. 6, when the SMF selects the UPF, it is not necessarily that the available UPF can be selected, that is, the SMF selected by the AMF does not necessarily select the available UPF, so the SMF selected by the AMF It may be invalid. If the selected SMF is invalid, the AMF needs to re-select the SMF. The re-selected SMF also needs to re-select the UPF. This results in a lower efficiency in selecting the SMF and brings a larger time to create a PDU session Delay.

In view of this, the technical solution of the embodiment of the present application is provided. By setting the state of the session management function network element 101, the selection of the session management function network element 101 can be made with reference to the state of the session management function network element 101, and the selected The session management function network element 101 can select available user plane function network elements, which improves the selection efficiency of the session management function network element 101 and reduces the delay in creating a session.

Among the network architectures shown in any one of FIGS. 2 to 4, the network elements related to the embodiment of the present application are mainly AMF, SMF, and NRF. Of course, the embodiment of the present application also relates to the UPF.

For the convenience of description, the following embodiments of the present application are all based on the application of the solutions provided in the embodiments of the present application to a 5G system, that is, in the following, the mobility management function network element is an AMF network element and session management. The function network element is an SMF network element, the network function repository function network element is an NRF network element, and the user plane function network element is a UPF. Further, the AMF network element is referred to as AMF, the SMF network element is referred to as SMF, the NRF network element is referred to as NRF, and the UPF network element is referred to as UPF. That is, the AMF described later in the embodiment of the present application can be replaced with a mobility management function network element, the SMF can be replaced with a session management function network element, the NRF can be replaced with a network function repository function network element, and the UPF can be replaced For the user plane function network element, for example, the SMF described later in the embodiment of the present application may be replaced with the session management function network element 101, and the NRF may also be replaced with the network function repository function network element 102.

The method for selecting a session management function network element provided in the embodiments of the present application will be specifically described below with reference to the accompanying drawings.

Please refer to FIG. 7, which is a flowchart of a method for selecting an SMF according to an embodiment of the present application. In the following description, the method is applied to the scenario shown in FIG. 2, FIG. 3, or FIG. 4 as an example. The method may be executed by the session management function network element 101 and the network function repository function network element 102 included in the system 100 for selecting a session management function network provided by the embodiment shown in FIG. 1, that is, SMF and NRF described below. Of course, during the implementation of this method, the mobility management function network element and the user plane function network element are also involved, that is, AMF and UPF described below. In addition, the embodiment of this application may include two processes. The first process, for example, is called a state synchronization process, which may occur before the PDU session is created, or it may occur in the process of creating a PDU session. The second process, for example, is called selection. The SMF process may occur during the process of creating a PDU session.

First, S701 to S706 are introduced. These steps belong to the state synchronization process described above, and occur before the PDU session is created or in the process of creating a PDU session.

S701. Configure a selection policy table for SMF and AMF.

To select a UPF for an SMF, it is necessary to select a UPF that meets the filtering conditions. Among them, when the SMF selects a UPF, it may choose based on one filtering condition or multiple filtering conditions. For a screening condition, the screening condition may include at least one parameter, for example, the screening condition may include DNN, or the screening condition may include S-NSSAI, or the screening condition may include DNN and S-NSSAI, of course In addition to DNN and / or S-NSSAI, the filter condition may include other parameters, such as some attribute parameters of UPF, or the filter condition may not include DNN and S-NSSAI, but Including other parameters, the embodiment of the present application is not limited. If the SMF is selected according to multiple filtering conditions, the parameters included in different filtering conditions may be the same, but the values of the parameters are different. For example, there are two kinds of screening conditions, and the parameters included in these two kinds of screening conditions are DNN, but the values of DNN in these two kinds of screening conditions are different. Or, different filtering conditions may include different parameters, such as one of them. One type of screening condition includes DNN, and the other type of screening condition includes DNN and S-NSSAI, which are not specifically limited. The filtering conditions used by the SMF when selecting the UPF can be pre-configured in the SMF. How many filtering conditions are configured and the parameters corresponding to each filtering condition can depend on the application scenario and the operator's configuration. Among them, if only one filtering condition is configured, it indicates that the SMF can support UPF of one type of characteristics, and if multiple filtering conditions are configured, it indicates that the SMF can support UPF of multiple types of characteristics. Because the AMF selects the SMF in the future, the filtering conditions can also be configured in the AMF. The filtering conditions configured in the AMF and the filtering conditions configured in the SMF may be the same or different.

In the embodiment of the present application, for example, the filtering conditions may be stored in a table, and the table may be called a selection policy table. The selection policy table may include at least one filtering condition. Then, the selection policy table may be configured for SMF and AMF. To configure the filter criteria.

To determine whether there is a UPF that meets the screening conditions, the SMF needs to obtain the UPF information, and then determine whether the UPF meets the screening conditions based on the UPF information. The UPF that the SMF can obtain information can be understood as the UPF associated with the SMF, or in the following, the SMF associated with the UPF may also be described as the SMF to which the UPF belongs. The following S702 to S704 introduce one way for the SMF to obtain UPF information.

S702. A UPF is deployed to the system and the configuration is completed.

Among them, after a UPF is deployed to the system, the UPF can be configured by OAM.

S703. The UPF sends a UPF instance information change message to the SMF through the N4 interface, and the SMF receives the UPF instance information change message through the N4 interface.

The UPF instance information change message is just a name and does not constitute a restriction on the message itself. The message is for the UPF to send the UPF attribute information to the SMF. As long as the message that can achieve this purpose can be a UPF instance information change message. In the embodiment of the present application, the attribute information of the UPF is also referred to as the information of the UPF. For example, it includes at least one of the UPF dynamic load, DNN, UE location information, S-NSSAI, and PDU session type. Of course, other information may also be included. information.

In the embodiment shown in FIG. 7, one UPF is deployed to the system as an example. In actual applications, there may be at least one UPF deployed to the system, and at least one UPF can send UPF information to the SMF, and thus the SMF It is possible to receive the information of the at least one UPF from at least one UPF, wherein one UPF sends only the information of the UPF to the SMF, and does not send information of other UPFs. Therefore, what the SMF receives from one UPF is The information of one UPF.

That is, after the UPF is deployed to the system, the UPF information can be actively sent to the SMF. If at least one UPF sends the UPF information to the SMF, the SMF can obtain at least one UPF information.

In the embodiment of the present application, the deployment of a new UPF to trigger the UPF to send UPF information to the SMF is taken as an example. Actually, it can also be applied to scenarios that need to update the UPF information, such as UPF update, UPF logout, or UPF load status change. Update, UPF can also send UPF information to. In these scenarios, only the trigger conditions have changed and the processing flow remains the same.

S704. The SMF classifies the information of the UPF into the UPF status parameter table.

After the SMF obtains the information of the UPF, it can directly store it, or it can also classify the information of the UPF. For example, the information of the UPF with the same parameters can be classified into one category. For example, the SMF can set the UPF status parameter table and group the UPF The information classification is saved in the UPF status parameter table. Among them, no matter what kind of storage method the SMF uses, the UPF information stored by the SMF refers to the available UPF information, and the availability here means that the UPF can normally provide external services. In addition, the SMF can also monitor the status of the UPF at any time. If the status of the UPF in the UPF status parameter table changes, such as offline, or sudden downtime, the SMF can remove such UPF information from the UPF status parameter table. Delete to ensure that all the available UPF information is stored in the UPF status parameter table. Among them, the UPF can complete the offline process through the deregistration process, and the SMF can know whether the UPF is offline. Regarding the downtime of the UPF, a detection mechanism can be maintained between the SMF and the UPF, such as the heartbeat detection mechanism. If the SMF cannot receive the heartbeat sent by the UPF, , It can be determined that the UPF is down, or the SMF can also determine whether the status of the UPF has changed through the notification of the NRF, thereby determining whether the UPF is available. The UPF status parameter table may include at least one UPF status, and one UPF status may correspond to at least one UPF information, that is, there may be at least one UPF that meets one UPF status. For example, please refer to Table 2 for an example of a UPF status parameter table:

Table 2

UPF状态(instance)IDUPF status (instance) ID	DNNDNN	S-NSSAIS-NSSAI
11	DNN_1DNN_1	S-NSSAI_1，S-NSSAI_2S-NSSAI_1, S-NSSAI_2
22	DNN_1DNN_1	S-NSSAI_1S-NSSAI_1
33	DNN_2DNN_2	S-NSSAI_3S-NSSAI_3

In Table 2, a type of UPF indicates a type of UPF, and a type of UPF will have some of the same attributes. The UPF status ID, that is, a number is set for the UPF status. 1, 2, and 3 in Table 2 represent three types of UPF. State, the parameters in the second column and the parameters in the third column are the parameters corresponding to the UPF state, that is, the parameters satisfied by a class of UPF. Of course, Table 2 is an example of setting the number for the UPF state. In practical applications, it is not necessary to set the number for the UPF state. That is, the first column in Table 2 can be removed, and Table 2 after the first column is removed. A line in it indicates a UPF status.

S705. The SMF decides whether SMF is available under the screening conditions.

The SMF needs to decide whether the SMF is available under the screening condition, that is, to determine whether a UPF is available under the screening condition, or to determine whether there is a UPF that meets the screening condition.

For example, there is a specific screening condition. This screening condition may be referred to as a first screening condition. Then, the SMF determines whether there is a UPF that meets the screening condition, and specifically determines whether there is a UPF that meets the first screening condition. Alternatively, there are multiple screening conditions. Two examples are used here, for example, the second screening condition and the third screening condition. Then, the SMF determines whether there is a UPF that meets the screening conditions. Specifically, it can determine whether there are UPF of the second screening condition, and determining whether there is a UPF that meets the third screening condition. If there are more kinds of screening conditions, the processing method is similar, so I won't go into details.

Refer to Table 3 for an example of the pre-configured selection strategy table in the SMF:

table 3

策略(Policy)IDPolicy ID	参数parameter
11	DNN:DNN_1,S-NSSAI:S-NSSAI_1DNN: DNN_1, S-NSSAI: S-NSSAI_1
22	DNN:DNN_3DNN: DNN_3

The strategies in Table 3 can be understood as the screening conditions. It can be seen that the selection strategy table shown in Table 3 includes two screening conditions. Among them, the policy ID is identification information set for the filtering conditions. The identification information may specifically be a number or the like, which is not limited in the embodiment of the present application, as long as it can distinguish different filtering conditions. 1 and 2 in Table 3 represent two kinds of filtering conditions. The parameters in the second column are the parameters corresponding to the filtering conditions. The identification information of the filtering conditions may also be set in advance, that is, the correspondence between the parameter information corresponding to the filtering conditions and the identification information of the filtering conditions is preset in the SMF. In the example in Table 3, the SMF can determine whether there are UPFs that meet these two screening conditions. In addition, in Table 3, the identification information is set as an example for the filtering conditions. In practical applications, the identification information may not be set for the filtering conditions. The selection strategy table shown in Table 3 becomes the selection strategy table shown in Table 4. :

Table 4

筛选条件Filter by
DNN:DNN_1,S-NSSAI:S-NSSAI_1DNN: DNN_1, S-NSSAI: S-NSSAI_1
DNN:DNN_3DNN: DNN_3

One row in Table 4 indicates one screening condition, and Table 4 includes two screening conditions.

In Tables 3 and 4, each screening condition corresponds to a specific parameter. In addition, there is also a case where a screening condition may not correspond to any parameter, that is, the parameter corresponding to the screening condition is empty, which means There is no need to screen UPF. As long as it can be found, it is a UPF that meets the screening conditions, or it can be understood that the screening condition is used to screen all UPFs. Of course, "all" means that it can be All available UPFs discovered by SMF. For example, when the screening condition is specifically the first screening condition, the first screening condition may correspond to some parameters, or the parameters corresponding to the first screening condition may be empty. If the parameter corresponding to the first screening condition is empty, it means that the first screening condition is used to screen all available UPFs. For another example, when the screening conditions are specifically the second screening condition and the third screening condition, the second screening condition and the third screening condition may both correspond to corresponding parameters; or, At least one of the filtering conditions may also be empty. If at least one of the second and third screening conditions is empty, it means that the at least one screening condition is used to screen all available UPFs, or it is understood that it indicates that at least one of the at least one screening condition is Each screening condition is used to screen all available UPFs.

After the SMF obtains the UPF information, it can directly determine whether the UPF information meets the screening conditions according to the screening conditions included in the selection policy table. For example, the SMF may obtain information of multiple UPFs, and the SMF does not classify and store the information of the UPFs during storage. Then the SMF may separately determine the information of each UPF to determine whether the information of each UPF meets the filtering conditions. Among them, the information of the UPF obtained by the SMF, or the information of the UPF used by the SMF to determine whether it meets the screening conditions, must be the information of the available UPF described above. In addition, there may be multiple screening conditions used by the SMF to determine. Then, for each UPF information obtained by the SMF, the SMF can determine whether the information of the UPF meets each of the multiple screening conditions. Among them, the information of a UPF meets a screening condition, which means that the UPF corresponding to the information of the UPF meets this screening condition.

Alternatively, if the SMF has a UPF status parameter table, the SMF can query the UPF status parameter table according to each filtering condition to determine whether there is a UPF that meets the filtering condition.

For example, the preset selection policy table in the SMF can refer to Table 3, the UPF information obtained by the SMF is stored in the UPF status parameter table, and the UPF status parameter table can refer to Table 2. The parameter corresponding to PolicyID = 1 in Table 3 matches UPFInstanceID = 1 and UPFInstanceInstanceID = 2 in Table2, and PolicyID = 2 in Table3 does not match UPF in Table2, that is, No UPF currently matches the Policy ID = 2 in Table 3.

Then the SMF can determine that the SMF is available under the first screening condition (Policy ID = 1) in the selection strategy table shown in Table 3. The SMF is the second screening in the selection strategy table shown in Table 3. The condition (Policy ID = 2) is unavailable.

It can be seen that, in the embodiment of the present application, since one or more filtering conditions may be set in the SMF in advance, if multiple filtering conditions are set, the same SMF can reflect multiple characteristics and expand the SMF. Application range.

The foregoing describes the situation in which the SMF has obtained UPF information. According to the foregoing description, if the SMF has obtained at least one UPF information, it can determine whether at least one UPF has a UPF that meets the filtering conditions based on the information of at least one UPF. . However, it is also possible that the SMF cannot obtain the UPF information. For example, the UPF can actively send the UPF information to the SMF, but the SMF has not received the UPF information sent by the UPF for the time being. In these cases, the SMF cannot obtain the UPF information. Or there is also a possibility that the UPF information obtained by the SMF is not available; or the SMF determines that the UPF stored in the UPF status parameter table is changed to an unavailable UPF, that is, it is considered that the previous introduction is all obtained by the SMF The situation of the available UPF information is reached. In this case, although the SMF has obtained the UPF information, these UPFs are not available. Unavailable here does not mean that the screening conditions are not met, but that it does not work properly, for example, the UPF is down or offline. Then, if the SMF does not obtain the UPF information, or the SMF does not obtain the available UPF information, the SMF can directly determine that there are no UPFs that meet the screening conditions, and it can be determined that the SMF is not available under the screening conditions.

If it is determined that there is a UPF that meets the filtering conditions, optionally, the SMF may set the state of the SMF to a state that is available under the filtering conditions.

As mentioned earlier, the screening conditions may be one or more. If there are multiple screening conditions, the SMF also judges whether there are UPFs that meet each of these screening conditions. Then, if the screening conditions are multiple , When the SMF sets the state of the SMF, it can also set the state of the SMF for each filtering condition.

For example, the screening condition is specifically the first screening condition. If there is a UPF that meets the first screening condition, the SMF can set the state of the SMF to be available under the first screening condition.

Alternatively, the screening conditions are specifically the second screening condition and the third screening condition. If there is a UPF that meets the second screening condition, the SMF can set the state of the SMF to be available under the second screening condition. The UPF that meets the third screening condition, the SMF can set the state of the SMF to be available under the third screening condition.

It can be seen that the state of the SMF is related to the filter condition. If the SMF stores the state of the SMF, the state of the SMF can be stored in correspondence with the filter condition. For example, if the filtering conditions are shown in Table 3, an additional column can be added to Table 3 to store the status of SMF. Please refer to Table 5 for this table. SMF can store Table 5, and Table 5 indicates which SMFs are filtered. Available under conditions.

table 5

策略(Policy)IDPolicy ID	状态status	参数parameter
11	可用Available	DNN:DNN_1,S-NSSAI:S-NSSAI_1DNN: DNN_1, S-NSSAI: S-NSSAI_1
22	Zh	DNN:DNN_3DNN: DNN_3

The second column of Table 5 indicates the status of the SMF. In addition, Table 5 is an example that combines the previous table with Table 2 and Table 3. In this example, the SMF is available under the first filter condition (Policy ID = 1). The status is unavailable under the second screening condition (Policy ID = 2), so in Table 5, the status of the SMF corresponding to the first screening condition (Policy ID = 1) is "available". Of course, the expression "available" here is just an example. For example, SMF can also indicate the state of SMF by 1 bit. If the bit is set to "1", it indicates that SMF is available. The embodiment of this application does not limit the state of SMF. Representation.

Or for example, if the filter conditions are shown in Table 4, you can add another column in Table 4 to store the status of SMF. Please refer to Table 6 for this table. SMF can store Table 6, and Table 6 shows which SMFs are in Available under filters.

Table 6

状态status	筛选条件Filter by
可用Available	DNN:DNN_1,S-NSSAI:S-NSSAI_1DNN: DNN_1, S-NSSAI: S-NSSAI_1
Zh	DNN:DNN_3DNN: DNN_3

The first column of Table 6 indicates the status of the SMF. In addition, Table 6 uses the filtering conditions indicated by the SMF in the first row of Table 6 as an example. Therefore, in Table 6, the first filtering condition (the first of Table 6 Line) The status of the corresponding SMF is "Available".

S706. If there is a UPF that meets the screening condition, the SMF sends the first status information of the SMF to the NRF, the NRF receives the first status information of the SMF from the SMF, and the first status information of the SMF is used to instruct the SMF to perform the screening. Available under conditions, the first state information is used to select an SMF.

For example, the SMF may call the NF management NF upgrade (Nnrf_NFManagement_NFUpdate) service method provided by the NRF to send the first state information of the SMF to the NRF.

As mentioned above, in this article, the state information used to indicate that SMF is available is called the first state information of SMF. For example, in Table 5, it is used to indicate that SMF is available under the first filter condition (Policy ID = 1). The state information of the state can be called the first state information of the SMF.

That is, although the SMF determines whether there are UPFs that meet the screening conditions, there may or may not be UPFs that meet the screening conditions, that is, the state of the SMFs under the screening conditions may be available. It may also be in an unavailable state, but in the embodiment of the present application, the SMF may send only the first state information of the SMF to the NRF, that is, the SMF only sends the information that the SMF is in the available state to the NRF, so the NRF can store only the available state SMF of the state. If there are multiple screening conditions, the SMF can only send the information that the SMF is available to the NRF. For example, for Table 5, the SMF can only make the SMF available under the first screening condition (Policy ID = 1). The status information is sent to the NRF. For the status information that the SMF is unavailable under the second screening condition (Policy ID = 2), the SMF may not send it to the NRF. In this case, the NRF can store only the information of the SMF in the available state. For example, the NRF can store the correspondence between the screening condition and the state of the SMF. As long as the NRF stores the correspondence, the SMF is in the available state. For example, the NRF can store the information in the first row of Table 6. Alternatively, the NRF can also store the identification information of the screening conditions, the screening conditions, and the state of the SMF. The corresponding relationship between these three is the same. As long as the NRF stores the corresponding relationship, the SMF is in the available state. For example, the NRF can store the information in the first row of Table 5.

Alternatively, the SMF may only send the second state information of the SMF to the NRF, and the second state information of the SMF may be used to indicate that the SMF is unavailable under the screening condition, that is, the SMF only sends the information that the SMF is in an unavailable state to the NRF. Therefore, the NRF can store only SMFs that are not available. If the filtering conditions are specific, the SMF can only send the information that the SMF is unavailable to the NRF. For example, for Table 5, the SMF can only make the SMF unavailable under the second filtering condition (Policy ID = 2). The state information of the state is sent to the NRF, and for the state information that the SMF is available under the first screening condition (Policy ID = 1), the SMF may not send it to the NRF. In this case, the NRF can store only the information of the SMF in the packet available state. For example, the NRF can store the correspondence between the filtering conditions and the state of the SMF. As long as the NRF stores the correspondence, it is unavailable. SMF. For example, the NRF can store the corresponding relationship between the filter condition and the state of the SMF, or the NRF can also store the identification information of the filter condition, the filter condition, and the state of the SMF. The corresponding relationship between the three is the same, as long as it is NRF stores the corresponding relationship, which are all unavailable SMFs.

In the embodiment of the present application, the first state information and the second state information of the SMF are collectively referred to as the state information of the SMF, that is, the state information of an SMF may include the first state information or the second state information of the SMF. As mentioned earlier, the first status information can have different implementations, and different implementations can implement different indications. Then, similarly, SMF status information also has different implementations, and different implementations can achieve different indications. Mode, for the same reason, the second status information of the SMF also has different implementations, and different implementations can implement different indication methods. The following mainly introduces the implementation of the status information of the SMF. The implementation of the second status information of the SMF can be And so on.

For example, the status information of the SMF includes information for indicating that the SMF is available under the screening condition, or includes information for indicating that the SMF is not available under the screening condition. This indication manner of the state information of the SMF can be considered as an implicit indication manner. That is, although the state information of the SMF directly indicates whether the SMF is available under the screening condition, it implicitly indicates whether the SMF has a UPF that satisfies the screening condition, that is, indicates the SMF by indicating the state of the SMF. Is there a UPF available?

For another example, the state information of the SMF includes information used to indicate that the SMF has a UPF that meets the screening condition. This indication manner of the state information of the SMF may be considered as an explicit indication manner. That is, the state information of the SMF directly indicates whether the SMF has a UPF that satisfies the screening condition, which is relatively simple and straightforward.

As for the indication method of the status information of the SMF, it can be predefined by the protocol, or it can also be determined through negotiation between the various network elements, and the like is not specifically limited. It can be seen that in the foregoing, the status information of the SMF is indicated by using the implicit indication as an example, and in the following, the status information of the SMF is also indicated by using the implicit indication as an example.

For an SMF, its status under a screening condition may change. For example, an SMF may have a UPF that meets the first screening condition at a moment. At this moment, the SMF is at the first screening condition. The following is the available status, but at the next moment, the SMF may not have a UPF that meets the first screening condition. For example, the UPF that meets the first screening condition may fail. At this moment, the SMF changes under the first screening condition. Is unavailable. Then, for the case where the NRF only stores the available SMF, if the SMF is the first state that sends the SMF to the NRF, the SMF can only send the first state information of the SMF to the NRF, that is, only the information that the SMF is available is sent, Not sending SMF is unavailable. For example, the SMF determines that the SMF is available under the second screening condition and is unavailable under the third screening condition. Then the SMF may send only the first state information to the NRF that the SMF is available under the second screening condition. No information is sent to the NRF that the SMF is unavailable under the third screening condition. However, if the SMF does not send the SMF status to the NRF for the first time, then regardless of whether the status of the SMF is available or unavailable, the SMF can be sent to the NRF so that the NRF can update the status of the SMF in a timely manner.

For example, the SMF does not send status information to the NRF for the first time. If the SMF determines that there is no UPF that meets the filtering conditions, the status of the SMF is unavailable under the filtering conditions, and the SMF can set the status of the SMF to be in the filtering The condition is unavailable under conditions. The SMF can send the second status information of the SMF to the NRF, and the second status information of the SMF can be used to indicate that the SMF is unavailable under the screening conditions. It can be understood that, in the embodiment of the present application, the state information of the SMF includes first state information and second state information of the SMF.

In the embodiment of the present application, the status information of the SMF may include parameter information corresponding to the screening condition and indication information for indicating whether the SMF is available under the screening condition. Then, the NRF may store the parameters corresponding to the screening condition. Information, and includes indication information for indicating whether the SMF is available under the screening condition, for example, the first state information of the SMF includes parameter information corresponding to the screening condition, and includes information for indicating that the SMF is available under the screening condition The second state information of the SMF includes parameter information corresponding to the screening condition, and includes indication information for indicating that the SMF is unavailable under the screening condition. Alternatively, the state information of the SMF may include parameter information corresponding to the screening condition, identification information of the screening condition, and indication information for indicating whether the SMF is available under the screening condition, and the NRF may store the information corresponding to the screening condition. Parameter information, identification information of the screening condition, and indication information including whether the SMF is available under the screening condition, for example, the first state information of the SMF includes parameter information corresponding to the screening condition, identification information of the screening condition, and It includes instruction information for indicating that the SMF is available under the screening condition, and the second state information of the SMF includes parameter information corresponding to the screening condition, identification information of the screening condition, and includes information for indicating that the SMF is under the screening condition. Unavailable instructions. Alternatively, the status information of the SMF may include identification information of the screening condition and indication information used to indicate whether the SMF is available under the screening condition, and the NRF may store identification information of the screening condition and include indication information Indication information of whether the SMF is available under the screening condition, for example, the first state information of the SMF includes identification information of the screening condition, and includes indication information for indicating that the SMF is available under the screening condition, and the second information of the SMF The status information includes identification information of the screening condition and indication information for indicating that the SMF is unavailable under the screening condition. In this case, the status information of the SMF may not include parameter information corresponding to the screening condition, then the SMF When sending SMF status information to the NRF, the amount of information that needs to be sent is small.

Or, as a special case, if the NRF only stores information of the available SMFs, and if subsequent SMFs become unavailable under the filtering conditions, the SMF sends a deletion instruction to the NRF, which is used to instruct the NRF to delete the filtering Information about the SMF under conditions. Then, the status information of the SMF may also include the parameter information corresponding to the screening condition and the identification information of the SMF, or the status information of the SMF includes the identification information of the screening condition and the identification information of the SMF, that is, because the SMF sends to the NRF all Is the available SMF information, so the status information sent by the SMF to the NRF may not include indication information indicating whether the SMF is available under the screening conditions. As long as the NRF receives the status information of the SMF, it can know that the SMF is Available SMFs under the appropriate screening conditions. If the state information of the SMF includes indication information indicating whether the SMF is available under the screening condition, a field for carrying the indication information needs to be added, and if the state information of the SMF does not include the indication of whether the SMF is available under the screening condition The instruction information does not need to be added with a field for carrying the instruction information, which helps to be compatible with the existing message format.

Or, as another special case, if the NRF only stores information of unavailable SMFs, and if subsequent SMFs become available under the filtering conditions, the SMF may also send a delete instruction to the NRF, and the delete instruction is used to indicate the NRF Delete the SMF information under the filter condition. Then, the status information of the SMF may also include the parameter information corresponding to the screening condition and the identification information of the SMF, or the status information of the SMF includes the identification information of the screening condition and the identification information of the SMF, that is, because the SMF sends to the NRF all Is the information of the unavailable SMF, so the status information sent by the SMF to the NRF may not include the indication information indicating whether the SMF is available under the screening conditions. As long as the NRF receives the status information of the SMF, it can know the SMF. Is an unavailable SMF under the corresponding filter condition. If the state information of the SMF includes indication information indicating whether the SMF is available under the screening condition, a field for carrying the indication information needs to be added, and if the state information of the SMF does not include the indication of whether the SMF is available under the screening condition The instruction information does not need to be added with a field for carrying the instruction information, which helps to be compatible with the existing message format.

However, in the following description, the state information of the SMF mainly includes the indication information for indicating whether the SMF is available under the screening condition as an example.

For example, the selection strategy table is shown in Table 3. The SMF determines that the SMF is available under the first screening condition included in the selection strategy table shown in Table 3. The second screening included in the selection strategy table shown in Table 3. If the condition is unavailable, you can add another column in Table 3 to store the status of the SMF. Please refer to Table 7 for this table. The SMF can store Table 7. Table 7 shows the conditions under which the SMF is available. And under which filters are not available.

Table 7

策略(Policy)IDPolicy ID	状态status	参数parameter
11	可用Available	DNN:DNN_1,S-NSSAI:S-NSSAI_1DNN: DNN_1, S-NSSAI: S-NSSAI_1
22	不可用unavailable	DNN:DNN_3DNN: DNN_3

The second column of Table 7 shows the status of the SMF. Of course, the expressions of "available" and "unavailable" here are just examples. For example, SMF can also indicate the status of SMF by 1 bit. If this bit is set to "1", it means that SMF is available. The bit is set to " “0” indicates that the SMF is in an unavailable state, and the embodiment of the present application does not limit the display manner of the SMF state. The first row of Table 7 can be regarded as a first state information of the SMF, and the second row can be regarded as a second state information of the SMF. Here, the first state information and the second state information are included to include the filtering conditions. The corresponding parameter information and the identification information of the filtering conditions are taken as an example. If the status information does not include the parameter information corresponding to the filtering conditions, for example, the first status information and the second status information include identification information corresponding to the filtering conditions, then Table 7 The third column can be removed. If the SMF sends status information to the NRF for the first time, it can send only the first line of information in Table 7. If the SMF does not send status information to the NRF for the first time, it can send all the information in Table 7.

Or, for example, the selection strategy table is shown in Table 4. The SMF determines that the SMF is available under the first screening condition included in the selection strategy table shown in Table 4, and the second type included in the selection strategy table shown in Table 4. If the condition is unavailable under the filter conditions, you can add another column in Table 4 to store the status of the SMF. Please refer to Table 8 for this table. The SMF can store Table 8. Table 8 shows the conditions under which the SMF is filtered. Available and under what filters.

Table 8

状态status	筛选条件Filter by
可用Available	DNN:DNN_1,S-NSSAI:S-NSSAI_1DNN: DNN_1, S-NSSAI: S-NSSAI_1
不可用unavailable	DNN:DNN_3DNN: DNN_3

The first column of Table 8 indicates the status of the SMF. In addition, Table 8 uses the filtering conditions indicated by the SMF in the first line of Table 8 as the available status and the filtering conditions indicated by the SMF on the second line of Table 8 as the unavailable status. Therefore, in Table 8, the status of the SMF corresponding to the first screening condition (the first row of Table 8) is "available", and the status of the SMF corresponding to the second screening condition (the second row of Table 8) is "Not Available" use". The first row of Table 8 can be regarded as a first state information of the SMF, and the second row can be regarded as a second state information of the SMF. Here, the first state information and the second state information are included to include filtering conditions. The corresponding parameter information is taken as an example. If the status information includes identification information of the filter condition, for example, the first status information and the second status information include identification information corresponding to the filter condition, then the second column in Table 8 can be replaced The identification information for the filter condition may be replaced with the first column of Table 7, for example. If the SMF sends status information to the NRF for the first time, it can send only the first line of information in Table 8. If the SMF does not send status information to the NRF for the first time, it can send all the information in Table 8.

Or, for the case where the NRF only stores information of the available SMF, if the SMF does not send status information to the NRF for the first time, then if the SMF determines that there is no UPF that meets the screening conditions, the SMF may not have to send the second status of the SMF to the NRF Instead, it can send a delete indication to the NRF, the delete indication being used to instruct the NRF to delete the information of the SMF from the information of the SMFs available under the filtering conditions. For example, if the first SMF initially has a UPF available under the first screening condition, then the first SMF is available under the first screening condition, and the first SMF takes the SMF as the first state that is available under the first screening condition. The information is sent to the NRF, and the NRF is stored. For example, the NRF can store the correspondence between the screening conditions and the available SMFs. Then the NRF can store at least one screening condition, each of which can correspond to the information of at least one SMF, and the SMF corresponding to each screening condition. Both are SMFs available under this filter. Then, if, subsequently, the first SMF has no available UPF under the first screening condition, then the first SMF becomes unavailable under the first screening condition, the first SMF may send a delete instruction to the NRF for indicating The NRF deletes the information of the first SMF corresponding to the first screening condition, and after receiving the deletion instruction, the NRF can delete the information of the first SMF in the information of the SMF corresponding to the first screening condition. The first SMF is no longer available SMF as soon as it is filtered.

Similarly, for the case where the NRF only stores the information of the SMF in the unavailable state, if the SMF does not send the state information to the NRF for the first time, then if the SMF determines that there is a UPF that meets the screening conditions, the SMF may not have to send the first It is a state information, but a deletion instruction may be sent to the NRF, and the deletion instruction is used to instruct the NRF to delete the information of the SMF from the information of the SMF that is not available under the screening condition.

What was introduced above is that the NRF only stores the information of the SMF in the available state. In the embodiment of the present application, the NRF may also store the information of the SMF in the unavailable state, that is, the NRF stores the information of the SMF in the available state and the information of the SMF in the available state. Unavailable state SMF information. Then, no matter if the SMF sends the SMF state information to the NRF for the first time or the SMF state information to the NRF subsequently, the SMF can send the first state information and the second state information to the NRF, so that NRF storage.

In addition, there may be one or more screening conditions. If the screening condition is the first screening condition, the SMF can send the status information of the SMF to the NRF. The status information of the SMF indicates whether the SMF is in the first screening condition. Available. Alternatively, the screening condition is specifically the second screening condition and the second screening condition, then it can be considered that the SMF sends a status message of the SMF to the NRF, the status information indicates whether the SMF is available in the second screening condition, and indicates that the SMF is in the third screening condition. Whether it is available under certain conditions; or, it can also be considered that the SMF sends two status information of the SMF to the NRF, one of which indicates whether the SMF is available in the second screening condition, and the other status information indicates that the SMF is in the third screening condition Is available. Of course, if the SMF sends the first state information of the SMF to the NRF, the method is similar, and I will not go into details.

As described in S701 to S706, these steps belong to the state synchronization process included in the embodiment of the present application, and occur before the PDU session is created or in the process of creating a PDU session. The following describes S707 to S708. These steps belong to the process of selecting an SMF included in the embodiment of the present application, and occur in the process of creating a PDU session.

S707. The AMF sends a request message to the NRF, and the NRF receives a request message from the AMF, where the request message is used to request information of an SMF that meets a fourth screening condition.

For example, the AMF can call the Nnrf_NFDiscovery_Request service method of the NRF to query the SMF that meets the fourth screening condition, that is, the AMF can call the Nnrf_NFDiscovery_Request service method of the NRF to send a request message to the NRF.

Among them, the filtering conditions used by AMF to select SMF and the filtering conditions used by SMF to select UPF can be the same concept, that is, as described above, in addition to the pre-configured filtering conditions in SMF, it is also necessary to use AMF. Filter conditions are pre-configured in. Alternatively, the filtering conditions can be configured only in the SMF, and the SMF sends the configured filtering conditions to the AMF, or the filtering conditions can be configured only in the AMF, and the AMF sends the configured filtering conditions to the SMF. For example, the fourth screening condition here may be the first screening condition described above, or may be the second screening condition or the third screening condition described above, or may be the same as the first screening condition described above. The conditions, the second screening condition, and the third screening condition are all different.

The AMF sends a request message to the NRF. The request message is used to request information about an SMF that meets the fourth screening condition. Here, the SMF that meets the fourth screening condition may mean that the SMF meets the fourth screening condition. The SMF of the screening condition may also mean that the SMF meets the fourth screening condition, and the SMF has a UPF that meets the fourth screening condition.

Among them, the form of the filtering conditions stored in AMF, SMF, and NRF may be corresponding. For example, the parameter information corresponding to the filtering conditions is stored in AMF, SMF, and NRF. Of course, the corresponding filtering conditions are stored in AMF and SMF. The parameter information stored in the NRF is the correspondence between the parameter information corresponding to the filtering conditions and the state information of the SMF. For another example, AMF, SMF, and NRF all store the identification information of the filter condition. Of course, AMF and SMF store the correspondence between the parameter information corresponding to the filter condition and the identification information of the filter condition. It can be the correspondence between the identification information of the screening condition and the status information of the SMF, or the correspondence between the identification information of the screening condition available in the NRF, the parameter information corresponding to the screening condition, and the status information of the SMF. .

If the correspondence between the parameter information corresponding to the filter condition and the status information of the SMF is stored in the NRF, the request message sent by the AMF can carry the parameter information corresponding to the fourth filter condition. In this way, the NRF can be directly clear. AMF needs query conditions. Or, if the correspondence between the identification information of the screening condition and the status information of the SMF is stored in the NRF, or the correspondence between the identification information of the screening condition, the parameter information corresponding to the screening condition and the status information of the SMF , The request message sent by the AMF can also carry the identification information of the fourth screening condition without carrying the parameter information corresponding to the fourth screening condition, which can reduce the amount of information exchanged between the AMF and the NRF, and save transmission resources.

After receiving the request message sent by the AMF, the NRF may determine whether there are available SMFs that satisfy the fourth screening condition according to the status information of at least one SMF, where the status information of the at least one SMF is used to indicate that the at least one SMF is in Whether it is available under the fourth screening condition.

The NRF may store the status information of at least one SMF. Among them, the status information of the at least one SMF may be from at least one SMF. For the manner in which the NRF obtains the status information of the SMF, and the content of the status information of the SMF, please refer to the foregoing. Introduction.

In the foregoing, different implementations of the state information of the SMF are introduced. Specifically, if the state information of the SMF is implicitly indicated, then for an SMF, the state information of the SMF may include an indication that the SMF is Information of available SMFs that satisfy the fourth screening condition, or information that indicates that the SMF is an unavailable SMF that meets the fourth screening condition; or, if the status information of the SMF is displayed in an indication manner, then For an SMF, the state information of the SMF may include information indicating that the SMF has a UPF meeting the fourth screening condition, or information indicating that the SMF does not have a UPF meeting the fourth screening condition. The “available SMFs that satisfy the fourth screening condition” can also be understood as the SMFs that are available under the fourth screening condition. “Available” here refers to whether there is a UPF that meets the fourth screening condition. The specific related content has been introduced in the foregoing, so I won't go into details.

If the request message carries parameter information corresponding to the fourth filtering condition, the SMF queries the parameter information corresponding to the fourth filtering condition when querying whether there are available SMFs that satisfy the fourth filtering condition, and if the request message carries the Is the identification information of the fourth filtering condition, the SMF performs an inquiry based on the identification information of the fourth filtering condition when inquiring whether there are available SMFs that satisfy the fourth filtering condition.

The state information of the SMF stored by the NRF may include only the first state information of the SMF, and may also include the first state information and the second state information of the SMF.

If the NRF only stores the first state information of the SMF, the NRF can query the information of the SMF corresponding to the stored fourth filtering condition. As long as the stored information of the SMF corresponding to the fourth filtering condition, the fourth filtering condition is satisfied. The information of the available SMFs, which meets the fourth screening condition and is available herein, means that these SMFs meet the fourth screening condition, and these SMFs all have UPFs available under the fourth screening condition. It can be seen that if the NRF only stores the first state information of the SMF, the NRF only needs to query whether there is corresponding SMF information under the fourth screening condition, and the method is relatively simple.

Or, if the NRF stores the first state information and the second state information of the SMF, the information of the SMF corresponding to the fourth filtering condition stored by the NRF may include both the information of the available SMFs and the unavailable ones. SMF information, then NRF can be processed in two ways:

In the first processing method, the NRF filters the available SMF information from the stored SMF information corresponding to the fourth screening condition. The SMF corresponding to the SMF information is the available SMF that meets the fourth screening condition. Of course, the premise is that The stored SMF information corresponding to the fourth screening condition includes available SMF information;

In the second processing method, the NRF determines all the stored SMF information corresponding to the fourth screening condition. The SMF corresponding to the SMF information may include available SMFs that meet the fourth screening condition, or may include satisfying the fourth screening condition. Unavailable SMF, or may include available SMFs that meet the fourth screening condition and unavailable SMFs that meet the fourth screening condition.

S708. The NRF sends the screening result to the AMF, and the AMF receives the screening result.

For example, the NRF can call the Nnrf_NFDiscovery_Request response service method of the NRF to send the screening results to the AMF.

The screening result indicates whether there are available SMFs that satisfy the fourth screening condition.

For example, the NRF may send a screening result to the AMF based on the Nnrf_NFDiscovery_Request service method of the NRF.

If the NRF only stores the first state information of the SMF, the NRF only needs to query whether there is corresponding SMF information under the fourth screening condition, for example, there are corresponding K SMF information under the fourth screening condition, then the NRF can set K The information of the SMFs is sent to the AMF as a screening result. The K SMFs are available SMFs that satisfy the fourth screening condition, and K is a positive integer. Alternatively, if there is no corresponding SMF information under the fourth screening condition, it indicates that there is no available SMF that meets the fourth screening condition, then the NRF can send a failure indication to the AMF, and the screening result at this time is the failure indication and the failure indication. It may indicate that no available SMF satisfies the fourth screening condition. For example, the NRF can send a screening result to the AMF by sending a message. One implementation of the failure indication is a message with empty content. If the message sent by the NRF to the AMF is empty, it indicates that the fourth filtering condition is not available. Or, another implementation of the failure indication is a specific indicator code, such as a failure code. If the message sent by the NRF to the AMF carries the indicator code, it indicates that the fourth filter condition is not available. SMF, the embodiment of the present application does not limit the implementation manner of the failure indication. Of course, if there are K available SMFs that satisfy the fourth screening condition, the NRF can carry the information of the K SMFs in the message and send it to the SMF.

In an implementation manner, if the NRF stores the first state information and the second state information of the SMF, and the NRF adopts the first processing method introduced in S605, then if the NRF query determines that the stored fourth filtering condition corresponds to The SMF information includes the available SMF information, and the NRF can send the information of the K SMFs as the screening result to the AMF, and these K SMFs are the available SMFs that satisfy the fourth screening condition. Alternatively, if there is no corresponding SMF information under the fourth screening condition, it indicates that there is no available SMF that meets the fourth screening condition, then the NRF can also send a failure indication to the AMF. For the introduction of the failure indication, refer to the content of the previous paragraph.

In another implementation, if the NRF stores the first state information and the second state information of the SMF, and the NRF adopts the second processing method introduced in S707, then the fourth filtering condition stored by the NRF query corresponds to For all the SMF information, as long as the fourth filter condition corresponds to the SMF information, the NRF can send the information of these SMFs to the AMF. Of course, the NRF can send the status information of these SMFs to the AMF. The SMFs available under the four screening conditions may either be SMFs that are not available under the fourth screening condition, or may include both SMFs that are available under the fourth screening condition and SMFs that are not available under the fourth screening condition, in short The NRF can be sent directly to the AMF without screening, which can be screened by the AMF. That is, the AMF may determine whether there is an available SMF that satisfies the fourth screening condition from the received SMF status information. If the NRF query determines that there is no corresponding SMF information in the fourth screening condition, the NRF can also send a failure indication to the AMF. For the introduction of the failure indication, please refer to the foregoing.

For example, the AMF may determine the status of the SMFs based on the received status information of the SMFs from the NRF. If it is determined that these SMFs are all SMFs available under the fourth screening condition, the AMF may select all or some of the SMFs in the SMFs; Alternatively, if it is determined that some of the SMFs are SMFs available under the fourth screening condition, and the remaining part of SMFs are SMFs that are not available under the fourth screening condition, the AMF may select the SMFs available under the fourth screening condition All or some of the SMFs in the SMF; or, if it is determined that these SMFs are all SMFs that are not available under the fourth screening condition, the AMF determines that there are no available SMFs that satisfy the fourth screening condition.

The information of the K SMFs sent by the NRF to the AMF may be the FQDN or IP address of the K SMFs, and of course, it may also be other information of the SMFs.

Through the technical solution provided by the embodiment of the present application, the information of the SMF obtained by the AMF can be the information of the available SMFs under the filtering conditions requested by the AMF, so that the AMF selects such SMFs, and when the SMF selects the UPF, Can choose the available UPF, try to avoid the situation that the SMF cannot select the available UPF, reduce the chance of the AMF reselecting the SMF, reduce the delay of the PDU session creation process, improve the efficiency of the SMF selection, and reduce the activation Odds of failure.

In order to solve the same technical problem, please refer to FIG. 8 again. This embodiment of the present application also provides a method for selecting a session management function network element. In the following description, this method is applied to FIG. 2, FIG. 3, or FIG. 4. The scenario shown is an example, and the method may be executed by the session management function network element 101 and the network function repository function network element 102 included in the system 100 for selecting a session management function network provided by the embodiment shown in FIG. The SMF and NRF described in the text, of course, also involve the mobility management function network element and the user plane function network element in the implementation process of the method, that is, the AMF and UPF described below. In addition, the embodiment of this application may include two processes. The first process, for example, is called a state synchronization process, which may occur before the PDU session is created, or it may occur in the process of creating a PDU session. The second process, for example, is called selection. The SMF process may occur during the process of creating a PDU session.

S801. Configure a selection policy table for SMF and AMF.

Regarding the introduction of S801, reference may be made to the introduction of S701 in the embodiment shown in FIG. 7. The content is the same, and details are not described repeatedly.

S802. The SMF sends a subscription request to the NRF, and the NRF receives the subscription request. The subscription request carries subscription parameters. The subscription parameters are information about the UPF that the SMF is interested in, that is, information about the UPF that the SMF needs to subscribe to. The subscription parameters include, for example, DNN, S-NSSAI, and SMF area identification.

For example, the SMF can call the Nnrf_NFManagement_NFStatusSubscribe service method of the NRF to initiate a subscription to the NRF, that is, call the Nnrf_NFManagement_NFStatusSubscribe service method of the NRF to send a subscription request to the NRF.

S803. The NRF sends a notification message to the SMF, and the SMF receives the notification message, and the notification message carries information about the UPF that currently meets the subscription parameters. In FIG. 8, the notification message in S803 is referred to as a first notification message.

For example, the NRF may call the Nnrf_NFManagement_NFStatusNotify service method to send a first notification message to the SMF.

Among them, if there is currently no UPF that meets the subscription parameters, the NRF may not need to perform S803, or the NRF executes S803, but in S803, the first notification message sent by the NRF to the SMF does not carry UPF information that meets the subscription parameters. Instead, it carries notification information, which is used to notify the SMF that there is currently no UPF that meets the subscription parameters.

The process by which the UPF sends UPF information to the NRF includes the following S804-S806. Among them, the following S804-S806 can also be understood as introducing the process that occurs after a new UPF is deployed to the system:

S804. A new UPF is deployed to the system and the configuration is completed.

The OAM system can configure the identification information of the NRF on the UPF and the attribute information for the UPF. That is, the information for configuring the UPF.

S805. The UPF sends a request message to the NRF, such as a third request message. The NRF receives the third request message, and the third request message carries the NF type of the UPF, the FQDN or the IP address of the N4 interface, and the OAM is the UPF. Configured attribute information.

For example, the UPF can call the NRF's Nnrf_NFManagement_NFRegister service method to register with the NRF, that is, call the NRF's Nnrf_NFManagement_NFRegister service method to send a third request message to the NRF.

S806. Due to the subscription operation of S802, if the information of the UPF meets the subscription parameters of the SMF, that is, the UPF complies with the subscription request of the SMF, the NRF can send a notification message to the SMF, and the SMF receives the notification message, and the notification message carries The UPF information. For example, the UPF information carried in the notification message may be the FQDN or IP address of the N4 interface of the UPF. In FIG. 8, the notification message in S806 is referred to as a second notification message.

Of course, if the information of the UPF does not meet the subscription parameters of the SMF, that is, the UPF does not meet the subscription request of the SMF, the NRF need not perform S806.

S807. The SMF classifies the information of the UPF into the UPF status parameter table.

Regarding the introduction to S807, reference may be made to the introduction to S704 in the embodiment shown in FIG. 7. The content is the same, and details are not described repeatedly.

S808. The SMF decides whether SMF is available under the screening conditions.

Regarding the introduction to S808, reference may be made to the introduction to S705 in the embodiment shown in FIG. 7. The content is the same, and details are not repeatedly described.

S809. The SMF sends the first state information of the SMF to the NRF, and the NRF receives the first state information of the SMF from the SMF. The first state information of the SMF is used to indicate that the SMF is available under the screening condition. The first state information Used to select SMF.

For example, the SMF may call the Nnrf_NFManagement_NFUpdate service method of the NRF to send the first state information of the SMF to the NRF.

Regarding the introduction of S809, reference may be made to the introduction of S706 in the embodiment shown in FIG. 7. The content is the same, and details are not described repeatedly.

As described in S801 to S809, these steps belong to the state synchronization process included in the embodiment of the present application. They occur before or during the process of creating a PDU session. The following describes S810 to S811. These steps belong to this step. The process of selecting an SMF included in the application embodiment occurs in the process of creating a PDU session.

S810. The AMF sends a request message to the NRF, and the NRF receives a request message from the AMF, and the request message is used to request information about an SMF that meets a fourth screening condition. In FIG. 8, the request message of S810 is referred to as a fourth request message, for example.

For example, the AMF can call the Nnrf_NFDiscovery_Request service method of the NRF to query the SMF that meets the fourth filtering condition, that is, the AMF can call the Nnrf_NFDiscovery_Request service method of the NRF to send a fourth request message to the NRF.

Regarding the introduction to S810, reference may be made to the introduction to S707 in the embodiment shown in FIG. 7. The content is the same, and details are not described repeatedly.

S811. The NRF sends the screening result to the AMF, and the AMF receives the screening result.

Regarding the introduction to S811, reference may be made to the introduction to S708 in the embodiment shown in FIG. 7. The content is the same, and details are not repeated.

In the embodiment of the present application, the SMF can obtain the UPF information by subscribing to the NRF. The SMF only needs to perform a subscription operation, and the subsequent information can be obtained directly from the UPF. The SMF does not need to send too much information, and it also reduces The interaction process between SMF and UPF.

In the embodiment shown in FIG. 7 and the embodiment shown in FIG. 8, the state of the SMF is set by the SMF, and the state information of the SMF is sent to the NRF. When the AMF requests the NRF, the NRF directly The state information of the SMF determines whether there are available SMFs that satisfy the filtering conditions requested by the AMF. In addition to this method, the state of the SMF can also be determined by the NRF, that is, the SMF does not need to set the state of the SMF, and the NRF can determine the state of the SMF by itself after receiving the request from the AMF.

In view of this, reference may be made to FIG. 9, an embodiment of the present application further provides a method for selecting a network element of a session management function. In the following introduction process, the method is continuously applied to the scenarios shown in FIG. 2, FIG. 3, or FIG. 4. For example, the method may be executed by the session management function network element 101 and the network function repository function network element 102 included in the system 100 for selecting a session management function network provided by the embodiment shown in FIG. 1, which is described below. SMF and NRF, of course, in the implementation process of this method, also involve mobility management function network elements and user plane function network elements, that is, AMF and UPF described below. In addition, the embodiment of the present application may also include two processes. Among them, S901 to S904 belong to the first process. The first process, for example, is also called the information acquisition process, which may occur before the PDU session is created, or it may occur during the PDU session creation. In the process, S905 and subsequent steps belong to the second process. The first process, such as the process of selecting SMF, may occur in the process of creating a PDU session.

S901. Configure a selection policy table for SMF and AMF.

Regarding the introduction of S901, reference may be made to the introduction of S701 in the embodiment shown in FIG. 7 or the introduction of S801 in the embodiment shown in FIG. 8. The content is the same and will not be described repeatedly.

S902. A new UPF is deployed to the system and the configuration is completed.

S903. The UPF sends a request message to the NRF, such as a third request message. The NRF receives the third request message. The third request message carries the NF type of the UPF, the FQDN or the IP address of the N4 interface, and the OAM is the UPF. Configured attribute information.

Regarding the introduction of S903, reference may be made to the introduction of S805 in the embodiment shown in FIG. 8. The content is the same, and details are not described repeatedly.

S904. The AMF sends a request message to the NRF, and the NRF receives a request message from the AMF, where the request message is used to request information about an SMF that meets a fourth screening condition. In FIG. 9, this request message is referred to as a fourth request message, for example.

Regarding the introduction of S904, reference may be made to the introduction of S707 in the embodiment shown in FIG. 7 or the introduction of S810 in the embodiment shown in FIG. 8. The content is the same, and details are not repeated.

S905. The NRF determines whether there are available SMFs that meet the fourth screening condition.

The NRF can query according to the fourth screening condition to determine whether there are SMFs that meet the fourth screening condition. If there are SMFs that meet the fourth screening condition, the NRF then determines whether these SMFs that meet the fourth screening condition are in the fourth screening. SMFs that can be used under conditions, that is, determine whether these SMFs have UPFs available under the fourth screening condition, or determine whether there are UPFs that meet the fourth screening condition among the UPFs associated with these SMFs. The UPF associated with the SMF includes a UPF that satisfies the fourth screening condition. Such an SMF is an available SMF that satisfies the fourth screening condition.

S906. The NRF sends the screening result to the AMF, and the AMF receives the screening result.

If the NRF determines that there are available SMFs that meet the fourth screening condition, the NRF can send the information of these SMFs to the AMF as the screening result. For example, the NRF can send the FQDN or IP address of these SMFs to the AMF as the screening result, of course. Other information that can be SMF is sent to the AMF as a screening result. Alternatively, if the NRF determines that there are no available SMFs for the fourth screening condition, the NRF may send a failure indication to the AMF. The failure indication may be used to indicate that no SMF is available for the fourth screening condition. For the failure indication, refer to FIG. 7. The related description of S708 in the embodiment is not repeated here.

In the embodiment of the present application, the SMF that satisfies the screening condition and can be selected can be selected by the NRF. The SMF is not required to set the state of the SMF, which reduces the burden of the SMF.

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

Based on the same inventive concept, as shown in FIG. 10, a schematic diagram of a device provided by the present application may be used. The device may be a session management function network element 101, a mobility management function network element, a network function repository function network element 102, or a chip. , The method of any of the above embodiments can be performed. When the device is a session management function network element 101 or a chip, the device 1000 may be configured to perform an operation performed by the SMF in the embodiment shown in any one of FIGS. 7 to 9. When the device is a mobility management function network element or chip, the device 1000 may be configured to perform an operation performed by the AMF in the embodiment shown in any one of the drawings in FIG. 7 to FIG. 9. When the device is a network function repository function network element 102 or a chip, the device 1000 may be configured to perform an operation performed by the NRF in the embodiment shown in any one of FIGS. 7 to 9.

The device 1000 includes at least one processor 1001, a communication line 1002, a memory 1003, and at least one communication interface 1004.

The processor 1001 may be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrations for controlling the execution of the program of the solution of the present application. Circuit.

The communication line 1002 may include a path for transmitting information between the aforementioned components.

The communication interface 1004 uses any device such as a transceiver to communicate with other devices or communication networks, such as Ethernet, radio access network (RAN), wireless local area networks (WLAN), Wired access network, etc.

The memory 1003 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (random access memory, RAM), or other types that can store information and instructions The dynamic storage device can also be electrically erasable programmable read-only memory (EEPROM-ready-only memory (EEPROM)), compact disc (read-only memory (CD-ROM)) or other optical disk storage, optical disk storage (Including compact discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or can be used to carry or store desired program code in the form of instructions or data structures and can be used by a computer Any other media accessed, but not limited to this. The memory may exist independently, and is connected to the processor through the communication line 1002. The memory can also be integrated with the processor.

The memory 1003 is configured to store a computer execution instruction for executing the solution of the present application, and the processor 1001 controls the execution. The processor 1001 is configured to execute computer execution instructions stored in the memory 1003, so as to implement the method for selecting a session management function network element provided by the foregoing embodiment of the present application.

Optionally, the computer-executable instructions in the embodiments of the present application may also be referred to as application program codes, which are not specifically limited in the embodiments of the present application.

In a specific implementation, as an embodiment, the processor 1001 may include one or more CPUs, such as CPU0 and CPU1 in FIG. 10.

In a specific implementation, as an embodiment, the apparatus 1000 may include multiple processors, such as the processor 1001 and the processor 1008 in FIG. 10. Each of these processors may be a single-CPU processor or a multi-CPU processor. A processor herein may refer to one or more devices, circuits, and / or processing cores for processing data (such as computer program instructions).

When the device shown in FIG. 10 is a chip, for example, it may be a chip of the session management function network element 101, or a chip of the mobility management function network element, or a chip of the network function repository function network element 102, the chip includes processing A processor 1001 (which may also include a processor 1008), a communication line 1002, a memory 1003, and a communication interface 1004. Specifically, the communication interface 1004 may be an input interface, a pin, or a circuit. The memory 1003 may be a register, a cache, or the like. The processor 1001 and the processor 1008 may be a general-purpose CPU, a microprocessor, an ASIC, or one or more integrated circuits for controlling program execution of a method for selecting a session management function network element in any of the foregoing embodiments.

The embodiments of the present application may divide the function modules of the device according to the foregoing method examples. For example, each function module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The above integrated modules may be implemented in the form of hardware or software functional modules. It should be noted that the division of the modules in the embodiments of the present application is schematic, and is only a logical function division. In actual implementation, there may be another division manner. For example, in the case where each functional module is divided according to each function, FIG. 11 shows a schematic diagram of a device. The device 1100 may be the session management function network element 101 involved in the foregoing embodiment, or may be the same as in the foregoing embodiment. The involved mobility management function network element is either the network function repository function network element 102 involved in the above embodiments, or the chip in the session management function network element 101, or the mobility management function network element. A chip, or a chip in the network element 102 of the network function storage library. The device 1100 includes a transceiver unit 1101 and a processing unit 1102.

In one embodiment, when the device 1100 is a chip of the session management function network element 101 or the session management function network element 101 of the foregoing embodiment, then,

A processing unit 1102, configured to determine whether there is a user plane function network element that meets the screening conditions;

The transceiver unit 1101 is configured to send the first state information of the session management function network element 101 to the network function repository function network element 102 if the processing unit 1102 determines that there is a user plane function network element that meets the screening condition. The first state information of the session management function network element 101 is used to indicate that the session management function network element 101 is available under the screening condition, and the first state information is used to select a session management function network element.

In a possible implementation manner, the first state information includes:

Information indicating that the session management function network element is available under the screening condition; or,

Information indicating that the session management function network element has a user plane function network element that meets the screening condition.

In a possible implementation manner, the processing unit 1102 is specifically configured to:

Acquiring information of at least one user plane function network element, and determining, according to the information of the at least one user plane function network element, whether there is a user plane function network element that meets the screening condition in the at least one user plane function network element; or,

The information of the user plane function network element is not obtained, and it is determined that there is no user plane function network element that meets the screening condition.

In a possible implementation manner, the processing unit 1102 used to obtain the information of at least one user plane function network element specifically includes:

For receiving information of the at least one user plane function network element from the at least one user plane function network element, wherein the information from the one user plane function network element is the information of the one user plane function network element; or,

Configured to send a subscription message to the network function repository function network element 102, where the subscription message is used to subscribe to information of a user plane function network element that meets the screening condition, and to receive information from the network function repository function network The notification message of the element 102 obtains information of the at least one user plane function network element according to the notification message.

For example, the processing unit 1102 may receive the information from the at least one user plane function network element of the at least one user plane function network element through the transceiver unit 1101, and send the information to the network function repository function network element 102 through the transceiver unit 1101. The subscription message may also receive a notification message from the network function repository function network element through the transceiver unit 1101.

In a possible implementation manner, the transceiver unit 1101 is further configured to:

If the processing unit 1102 determines that there is no user plane function network element that meets the screening condition, sending the second state information of the session management function network element 101 to the network function repository function network element 102, the session management function The second state information of the network element 101 is used to indicate that the session management function network element 101 is unavailable under the screening condition; or,

If the processing unit 1102 determines that there is no user plane function network element that meets the screening conditions, a delete instruction is sent to the network function repository function network element 102, and the delete instruction is used to instruct the network function repository function network element 102 , Deleting the information of the session management function network element 101 from the information of the session management function network element available under the screening condition.

In one possible implementation,

The screening condition is specifically a first screening condition, and the processing unit 1102 is configured to determine whether there is a user plane function network element that meets the screening condition, and specifically includes:

Determining whether there is a user plane function network element that meets the first screening condition;

or,

The screening conditions are specifically the second screening condition and the third screening condition, and the processing unit 1102 is configured to determine whether there is a user plane function network element that meets the screening conditions, and specifically includes:

Determining whether there is a user plane function network element that meets the second screening condition, and determining whether there is a user plane function network element that meets the third screening condition.

In a possible implementation manner, the transceiver unit 1101 is configured to send the first state information of the session management function network element 101 to the network function repository function network element 102 if there is a user plane function network element that meets the screening condition. The first state information of the session management function network element 101 is used to indicate that the session management function network element 101 is available under the screening condition, and includes:

The screening condition is specifically the first screening condition. If the processing unit 1101 determines that there is a user plane function network element that meets the first screening condition, the transceiver unit 1101 sends the first state information of the session management function network element 101 to The network function repository function network element 102, the first state information of the session management function network element 101 is used to indicate that the session management function network element 101 is available under the first screening condition;

or,

The screening condition is specifically the second screening condition and the third screening condition. If the processing unit 1101 determines that there is a user plane function network element that meets the second screening condition, the transceiver unit 1101 sets the session management function network element 101 Sending the first state information of the network function storage network element 102 to the network function repository, and the first state information of the session management function network element 101 is used to indicate that the session management function network element is available under the second screening condition; or The processing unit 1101 determines that there is a user plane function network element that meets the third screening condition, and the transceiver unit 1101 sends the first state information of the session management function network element 101 to the network function repository function network element 102, and the session management function network element The first state information of 101 is used to indicate that the session management function network element 101 is available under the third screening condition.

In one possible implementation,

When the screening condition is specifically the first screening condition, if the first screening condition is empty, it means that the first screening condition is used to screen all user plane function network elements; or,

When the screening condition is specifically the second screening condition and the third screening condition, if at least one of the second screening condition and the third screening condition is empty, it means that the at least one screening condition Conditions are used to filter all user plane function network elements.

In one possible implementation,

The first state information of the session management function network element 101 includes parameter information corresponding to the screening condition, and includes indication information for indicating that the session management function network element 101 is available under the screening condition; or,

The first state information of the session management function network element 101 includes identification information of the screening condition, and includes indication information for indicating that the session management function network element 101 is available under the screening condition.

In another embodiment, when the device 1100 is a chip of the network function repository function network element 102 or the network function repository function network element 102 of the above embodiment, then,

The transceiver unit 1101 is configured to receive a request message from a mobility management function network element, where the request message is used to request information about a session management function network element 101 that meets a fourth screening condition;

A processing unit 1102 is configured to determine, according to the status information of at least one session management function network element 101, whether there is an available session management function network element 101 that meets the fourth screening condition, wherein the at least one session management function network element The state information of 101 is used to indicate whether the at least one session management function network element 101 is in an available state under the fourth screening condition;

The transceiver unit 1101 is further configured to send a screening result to the mobility management function network element.

In a possible implementation manner, the state information of a session management function network element 101 includes:

Information indicating that the one session management function network element 101 is an available session management function network element 101 that meets the fourth screening condition, or indicating that the one session management function network element 101 is a Information of the unavailable session management function network element 101; or,

Information indicating that the one session management function network element 101 has a user plane function network element that satisfies the fourth screening condition, or indicates that the one session management function network element 101 does not have a user plane that meets the fourth screening condition Information about the functional NEs.

In one possible implementation,

The filtering result is specifically information of K session management function network elements 101, where the information of the K session management function network elements 101 is used to indicate that the K session management function network elements 101 meet the fourth Available session management function network element 101 for the filter condition; or,

The screening information is specifically a failure indication, wherein the failure indication indicates that the available session management function network element 101 that does not meet the fourth screening condition is available.

In a possible implementation manner, the state information of the at least one session management function network element 101 is from at least one session management function network element 101.

In one possible implementation,

The state information of one session management function network element 101 among the at least one session management function network element 101 includes parameter information corresponding to at least one screening condition, and includes information indicating that the one session management function network element 101 is in Indication information of availability of each of the at least one screening condition, the at least one screening condition including the fourth screening condition; or,

The state information of one session management function network element 101 among the at least one session management function network element 101 includes identification information of at least one filtering condition, and includes information used to indicate that the one session management function network element 101 is in the Indication information indicating whether each of the at least one screening condition is available, and the at least one screening condition includes the fourth screening condition.

It should be understood that the apparatus may be used to implement the steps performed by the session management function network element 101, the mobility management function network element, and the network function repository function network element 102 in the method of the embodiment of the present application. For related features, refer to the foregoing. I won't repeat them here.

Specifically, the function / implementation process of the transceiver unit 1101 and the processing unit 1102 in FIG. 11 may be implemented by the processor 1001 in FIG. 10 calling a computer execution instruction stored in the memory 1003. Alternatively, the function / implementation process of the processing unit 1102 in FIG. 11 may be implemented by the processor 1001 in FIG. 10 calling a computer execution instruction stored in the memory 1003, and the function / implementation process of the transceiver unit 1101 in FIG. 11 may be performed through the graph. The communication interface 1004 in 10 is implemented.

Optionally, when the device 1000 is a chip or a circuit, the function / implementation process of the transceiver unit 1101 may also be implemented through pins or circuits. Optionally, when the device 1000 is a chip, the memory 1003 may be a storage unit in the chip, such as a register, a cache, and the like. Of course, when the device 1000 is a session management function network element 101, such as the session management function network element 101 in the foregoing embodiment, the memory 1003 may also be a storage unit located outside the chip in the session management function network element 101. This application The embodiment does not specifically limit this. When the device 1000 is the network function repository function network element 102, the memory 1003 may also be a storage unit located outside the chip in the network function repository function network element 102, which is not specifically limited in this embodiment of the present application.

In the above embodiments, it may be implemented in whole or in part 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. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions according to the embodiments of the present application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. 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 from a website site, computer, server, or data center Transmission by wire (for example, coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (for example, infrared, wireless, microwave, etc.) to another website site, computer, server, or data center. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, a data center, and the like that includes one or more available medium integration. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)).

Various illustrative logic units and circuits described in the embodiments of the present application may be implemented by a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), and field programmable A gate-array (field-programmable gate array, FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination of the above is designed to implement or operate the described functions. The general-purpose processor may be a microprocessor. Alternatively, the general-purpose processor may also be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented by a combination of computing devices, such as a digital signal processor and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration. achieve.

The steps of the method or algorithm described in the embodiments of the present application may be directly embedded in hardware, a software unit executed by a processor, or a combination of the two. A software unit may be stored in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium in the art. For example, the storage medium may be connected to the processor, so that the processor can read information from the storage medium and can 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 be provided in an ASIC, and the ASIC may be provided in a terminal device. Alternatively, the processor and the storage medium may also be provided in different components in the terminal device.

These computer program instructions can also be loaded on a computer or other programmable data processing device, so that a series of steps can be performed on the computer or other programmable device to produce a computer-implemented process, and the The instructions provide steps for implementing the functions specified in one or more flowcharts and / or one or more blocks of the block diagrams.

Although the embodiments of the present application have been described in combination with specific features and embodiments thereof, it is obvious that various modifications and combinations can be made without departing from the spirit and scope of the embodiments of the present application. Accordingly, the embodiments and drawings of the present application are merely exemplary illustrations of the embodiments of the present application as defined by the appended claims, and are deemed to have covered any and all modifications, changes, combinations, or equivalents within the scope of the embodiments of the present application. Thing. Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present application without departing from the scope of the embodiments of the present application. In this way, if these 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 equivalent technologies, the embodiments of the present application are also intended to include these changes and modifications.

Claims

A method for selecting a session management function network element, comprising:

Determine whether there are user plane function network elements that meet the screening conditions;

If there is a user plane function network element that meets the screening condition, the first state information of the session management function network element is sent to the network function repository function network element, and the first state information of the session management function network element is used. For indicating that the session management function network element is available under the screening condition, the first state information is used to select a session management function network element.
The method according to claim 1, wherein the first state information comprises:

Information indicating that the session management function network element is available under the screening condition; or,

Information indicating that the session management function network element has a user plane function network element that meets the screening condition.
The method according to claim 1 or 2, characterized in that determining whether there is a user plane function network element that meets the filtering conditions comprises:

Acquiring information of at least one user plane function network element, and determining, according to the information of the at least one user plane function network element, whether there is a user plane function network element that meets the screening condition in the at least one user plane function network element; or,

The information of the user plane function network element is not obtained, and it is determined that there is no user plane function network element that meets the screening condition.
The method according to claim 3, wherein acquiring information of at least one user plane function network element comprises:

Receiving information of the at least one user plane function network element from the at least one user plane function network element, wherein the information from the one user plane function network element is the information of the one user plane function network element; or,

Sending a subscription message to the network function repository function network element, the subscription message being used to subscribe to information of a user plane function network element that meets the screening condition, and receiving a notification from the network function repository function network element A message to obtain information of the at least one user plane function network element according to the notification message.
The method according to any one of claims 1-4, wherein the screening condition comprises at least one of a data network name DNN and a single network slice selection support information S-NSSAI.
The method according to any one of claims 1-5, further comprising:

If there is no user plane function network element that meets the screening condition, sending the second state information of the session management function network element to the network function repository function network element, the second state of the session management function network element The information is used to indicate that the session management function network element is unavailable under the screening condition; or,

If there is no user plane function network element that meets the screening conditions, a delete instruction is sent to the network function repository function network element, where the delete instruction is used to instruct the network function repository function network element, Delete the information of the session management function network element from the information of the session management function network element available under the conditions.
The method according to any one of claims 1-6, wherein:

The screening condition is specifically a first screening condition, and determining whether there is a user plane function network element that meets the screening condition includes:

Determining whether there is a user plane function network element that meets the first screening condition;

or,

The screening condition is specifically the second screening condition and the third screening condition, and determining whether there is a user plane function network element that meets the screening condition includes:

Determining whether there is a user plane function network element that meets the second screening condition, and determining whether there is a user plane function network element that meets the third screening condition.
The method according to claim 7, wherein if there is a user plane function network element that meets the screening condition, sending the first state information of the session management function network element to a network function repository function network element, The first state information of the session management function network element for indicating that the session management function network element is available under the screening condition includes:

The screening condition is specifically the first screening condition. If there is a user plane function network element that meets the first screening condition, the first state information of the session management function network element is sent to the network function repository function network. Element, the first state information of the session management function network element is used to indicate that the session management function network element is available under the first screening condition;

or,

The screening condition is specifically the second screening condition and the third screening condition. If there is a user plane function network element that meets the second screening condition, the first state information of the session management function network element is sent. To the network function repository function network element, the first state information of the session management function network element is used to indicate that the session management function network element is available under the second screening condition; or The user plane function network element of the third screening condition sends the first state information of the session management function network element to a network function repository function network element, and the first state information of the session management function network element is used for And instructing the session management function network element to be available under the third screening condition.
The method according to any one of claims 1-8, characterized in that:

When the screening condition is specifically the first screening condition, if the first screening condition is empty, it means that the first screening condition is used to screen all user plane function network elements; or,

When the screening condition is specifically the second screening condition and the third screening condition, if at least one of the second screening condition and the third screening condition is empty, it means that the at least one screening condition Conditions are used to filter all user plane function network elements.
The method according to any one of claims 1-9, wherein:

The first state information of the session management function network element includes parameter information corresponding to the screening condition, and includes indication information for indicating that the session management function network element is available under the screening condition; or,

The first state information of the session management function network element includes identification information of the screening condition, and includes indication information for indicating that the session management function network element is available under the screening condition.
A method for selecting a session management function network element, comprising:

Receiving a request message from a mobility management function network element, where the request message is used to request information about a session management function network element that meets a fourth screening condition;

Determining, according to the status information of at least one session management function network element, whether there is an available session management function network element that meets the fourth screening condition, wherein the status information of the at least one session management function network element is used to indicate the Whether at least one session management function network element is available under the fourth screening condition;

Sending a screening result to the mobility management function network element.
The method according to claim 11, wherein the state information of a session management function network element comprises:

Information indicating that the one session management function network element is an available session management function network element that meets the fourth screening condition, or indicating that the one session management function network element is an unavailable Information about the network element of the session management function; or,

Information indicating that the one session management function network element has a user plane function network element that meets the fourth screening condition, or indicates that the one session management function network element does not have a user plane function network that meets the fourth screening condition Meta information.
The method according to claim 11 or 12, wherein:

The screening result is specifically information of K session management function network elements, where the information of the K session management function network elements is used to indicate that the K session management function network elements are the ones that satisfy the fourth screening condition. Available session management function network elements; or,

The screening information is specifically a failure indication, where the failure indication indicates that no available session management function network element satisfies the fourth screening condition.
The method according to any one of claims 11-13, wherein the method further comprises:

The state information of the at least one session management function network element is from at least one session management function network element.
The method according to any one of claims 11 to 14, wherein:

The state information of one session management function network element among the at least one session management function network element includes parameter information corresponding to at least one filtering condition, and includes information for instructing the one session management function network element in the at least one Indication information of whether a screening condition is available under each of the screening conditions, the at least one screening condition includes the fourth screening condition; or,

The state information of one session management function network element among the at least one session management function network element includes identification information of at least one filtering condition, and includes information for indicating that the one session management function network element is in the at least one Indication information of whether each of the screening conditions is available, the at least one screening condition includes the fourth screening condition.
A system for selecting a network element for a session management function, comprising:

The session management function network element is used to determine whether there is a user plane function network element that meets the screening condition. If there is a user plane function network element that meets the screening condition, the first state information of the session management function network element is sent to Network function repository function network element, the first state information of the session management function network element is used to indicate that the session management function network element is available under the screening condition, and the first state information is used to select a session management function Network element

The network function repository function network element is configured to receive the first status information.
The method according to claim 16, wherein the first state information comprises:

Information indicating that the session management function network element is available under the screening condition; or,

Information indicating that the session management function network element has a user plane function network element that meets the screening condition.
The system according to claim 16 or 17, wherein the network function repository function network element is further configured to:

Receiving a request message from a mobility management function network element, the request message is used to request information about a session management function network element that meets a fourth screening condition; wherein the session management function network element that meets the fourth screening condition Means that the session management function network element has a user plane function network element that satisfies the fourth screening condition;

Determining, according to the status information of at least one session management function network element, whether there is an available session management function network element that meets the fourth screening condition, wherein the status information of the at least one session management function network element is used to indicate the Whether at least one session management function network element is available under the fourth screening condition;

Sending a screening result to the mobility management function network element.
A device, comprising:

A processing unit, which is used to determine whether there is a user plane functional network element that meets the screening conditions;

A transceiver unit, configured to send the first state information of the session management function network element to the network function repository function network element if the processing unit determines that there is a user plane function network element that meets the screening condition, and the session The first status information of the management function network element is used to indicate that the session management function network element is available under the screening condition, and the first status information is used to select the session management function network element.
The apparatus according to claim 19, wherein the first state information comprises:

Information indicating that the session management function network element is available under the screening condition; or,

Information indicating that the session management function network element has a user plane function network element that meets the screening condition.
The apparatus according to claim 19 or 20, wherein the processing unit is specifically configured to:

Acquiring information of at least one user plane function network element, and determining, according to the information of the at least one user plane function network element, whether there is a user plane function network element that meets the screening condition in the at least one user plane function network element; or,

The information of the user plane function network element is not obtained, and it is determined that there is no user plane function network element that meets the screening condition.
The apparatus according to claim 21, wherein the processing unit for acquiring information of at least one user plane function network element specifically comprises:

For receiving information of the at least one user plane function network element from the at least one user plane function network element, wherein the information from the one user plane function network element is the information of the one user plane function network element; or,

Configured to send a subscription message to the network function repository function network element, where the subscription message is used to subscribe to information of a user plane function network element that meets the screening condition, and to receive a message from the network function repository function network element And obtaining information of the at least one user plane function network element according to the notification message.
The device according to any one of claims 19 to 22, wherein the transceiver unit is further configured to:

If the processing unit determines that there is no user plane function network element that meets the screening condition, sending the second state information of the session management function network element to the network function repository function network element, the session management function network The second state information of the meta is used to indicate that the session management function network element is unavailable under the screening condition; or,

If the processing unit determines that there is no user plane function network element that meets the screening condition, sending a delete instruction to the network function repository function network element, where the delete instruction is used to instruct the network function repository function network element, Delete the information of the session management function network element from the information of the session management function network element available under the screening condition.
The device according to any one of claims 19-23, wherein:

The screening condition is specifically a first screening condition, and the processing unit for determining whether there is a user plane function network element that meets the screening condition specifically includes: determining whether there is a user plane function network element that meets the first screening condition;

or,

The screening condition is specifically a second screening condition and a third screening condition, and the processing unit is configured to determine whether there is a user plane function network element that meets the screening condition. The processing element specifically includes: determining whether there is a user plane that meets the second screening condition. A functional network element, and determining whether there is a user plane functional network element that meets the third screening condition.
The device according to claim 24, wherein the transceiver unit is configured to: if the processing unit determines that there is a user plane function network element that meets the screening condition, change the first state of the session management function network element The information is sent to a network function repository function network element, and the first state information of the session management function network element is used to indicate that the session management function network element is available under the screening condition, including:

The screening condition is specifically the first screening condition. If the processing unit determines that there is a user plane function network element that meets the first screening condition, the transceiver unit sets the first state of the session management function network element. The information is sent to a network function repository function network element, and the first state information of the session management function network element is used to indicate that the session management function network element is available under the first screening condition;

or,

The screening condition is specifically the second screening condition and the third screening condition. If the processing unit determines that there is a user plane function network element that meets the second screening condition, the transceiver unit manages the session. The first status information of the function network element is sent to the network function repository function network element, and the first status information of the session management function network element is used to indicate that the session management function network element is under the second screening condition. Available; or, if there is a user plane function network element that meets the third screening condition, the transceiver unit sends the first state information of the session management function network element to a network function repository function network element, the session The first state information of the management function network element is used to indicate that the session management function network element is available under the third screening condition.
A device, comprising:

A transceiver unit, configured to receive a request message from a mobility management function network element, where the request message is used to request information about a session management function network element that meets a fourth screening condition;

A processing unit, configured to determine, according to the status information of at least one session management function network element, whether there is an available session management function network element that satisfies the fourth screening condition, wherein the status information of the at least one session management function network element Configured to indicate whether the at least one session management function network element is in an available state under the fourth screening condition;

The transceiver unit is further configured to send a screening result to the mobility management function network element.
The apparatus according to claim 26, wherein the state information of a session management function network element comprises:

Information indicating that the one session management function network element is an available session management function network element that meets the fourth screening condition, or indicating that the one session management function network element is an unavailable one that meets the fourth screening condition Information about the network element of the session management function; or,

Information indicating that the one session management function network element has a user plane function network element that meets the fourth screening condition, or indicates that the one session management function network element does not have a user plane function network that meets the fourth screening condition Meta information.
The device according to claim 26 or 27, wherein

The screening result is specifically information of K session management function network elements, where the information of the K session management function network elements is used to indicate that the K session management function network elements are the ones that satisfy the fourth screening condition. Available session management function network elements; or,

The screening information is specifically a failure indication, where the failure indication indicates that no available session management function network element satisfies the fourth screening condition.
A communication device, comprising: a processor and a memory; the memory is configured to store a computer execution instruction, and when the communication device is running, the processor executes the computer execution instruction stored in the memory, In this way, the communication device executes the method for selecting a session management function network element according to any one of claims 1-10.
A communication device, comprising: a processor and a memory; the memory is configured to store a computer execution instruction, and when the communication device is running, the processor executes the computer execution instruction stored in the memory, In this way, the communication device executes the method for selecting a network element for a session management function according to any one of claims 11-15.
A processing device, comprising:

Memory for storing computer programs;

A processor, configured to call and run the computer program from the memory to execute the method of selecting a session management function network element according to any one of claims 1-10, or any one of claims 11-15.
A processor, which is configured to execute the method for selecting a network element for a session management function according to any one of claims 1-10, or any one of claims 11-15.
A chip system is characterized in that it includes:

Memory for storing computer programs;

A processor, configured to call and run the computer program from the memory, so that a device having the chip system installed executes the selection according to any one of claims 1-10, or any one of claims 11-15 Method of session management function network element.
A computer-readable storage medium including a computer program, which when run on a computer, causes the computer to perform the selection session management according to any one of claims 1-10, or any one of claims 11-15 Functional network element method.
A computer program product, the computer program product comprising a computer program, when the computer program is run on a computer, causing the computer to execute any one of claims 1-10, or any one of claims 11-15 Method for selecting a session management function network element.
An apparatus for performing a method for selecting a network element for a session management function according to any one of claims 1-10.
An apparatus for performing a method for selecting a network element for a session management function according to any one of claims 11-15.