WO2022267688A1

WO2022267688A1 - Method and apparatus for discovering standby smf, and electronic device and medium

Info

Publication number: WO2022267688A1
Application number: PCT/CN2022/089810
Authority: WO
Inventors: 叶海洋
Original assignee: 中兴通讯股份有限公司
Priority date: 2021-06-23
Filing date: 2022-04-28
Publication date: 2022-12-29
Also published as: CN115514797A

Abstract

Provided in the present disclosure is a method for discovering a standby SMF. The method comprises: in response to the reception of an NF discovery request message sent by an NF, acquiring a selection parameter carried in the NF discovery request message, wherein the NF sends the NF discovery request message when it is detected that a first SMF corresponding to the current session has a fault; according to a mapping relationship between information of an SMF and the selection parameter, determining information of a second SMF corresponding to the selection parameter, wherein the first SMF and the second SMF belong to the same SMF cluster of the same SMF set, and SMFs in the same SMF cluster have a mutual active-standby relationship, manage the same session, and are configured with the same selection parameter; and sending, to the NF, an NF discovery response message carrying the information of the second SMF. Further provided in the present disclosure are an apparatus for discovering a standby SMF, and an electronic device and a readable medium.

Description

Alternate SMF discovery method, apparatus, electronic device and medium

technical field

The present disclosure relates to the technical field of communication, and in particular to a backup SMF discovery method, device, electronic equipment and medium.

Background technique

Application scenarios in vertical industries (such as coal mines, electric power, industrial control, etc.) require ultra-high reliability and ultra-low latency. 3GPP (3rd Generation Partnership Project, Third Generation Partnership Project) classifies such scenarios into uRLLC (Ultra reliable and low latency communication, ultra-reliable and ultra-low-latency communication), and proposed an end-to-end session redundancy scheme to improve reliability. This scheme establishes two PDU (Protocol Data Unit, protocol data unit) session.

In the uRLLC dual PDU session redundancy scheme, two redundant PDU sessions need to be established on two different SMFs (Session Management Function, session management function entity). When these two SMFs are in a SMF group (Set), and when one of the SMFs fails, if the NF (Network Function, network function node) randomly selects a SMF from the SMF group as the backup SMF, then it is possible to Two redundant PDU sessions are connected to the same SMF, which does not meet the end-to-end redundancy requirements and reduces reliability.

After the backup SMF is selected, in order to ensure that the two redundant PDU sessions can be connected to two different SMFs, there is currently a backup SMF discovery scheme: when the SMF fails, first obtain the SMF group where the faulty SMF is located. All SMF information of the SMF, and then select the standby SMF of the faulty SMF. However, the process of selecting a backup SMF in this scheme is relatively complicated.

uRLLC is widely used in vertical industries, so there are a large number of users. For an SMF that carries millions of sessions, when it fails, if the above-mentioned solution is used to reselect a backup SMF, the above-described steps need to be executed for each session. Complicated processing procedures will greatly consume resources, and may even cause core network load overload.

Contents of the invention

An embodiment of the present disclosure provides a backup SMF discovery method, including: in response to receiving the NF discovery request message sent by the NF, acquiring the selection parameters carried therein, wherein the NF detects that the first SMF corresponding to the current session fails Send the NF discovery request message, the selection parameters include the identification of the SMF group and the service parameters, and the identification of the SMF group is the identification of the SMF group where the first SMF is located; according to the information between the SMF and the selection parameters The mapping relationship is to determine the information of the second SMF corresponding to the selection parameter, wherein the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and the SMFs in the same SMF cluster have a master-backup relationship with each other , managing the same session and configured with the same selection parameters; and sending an NF discovery response message carrying the information of the second SMF to the NF.

The embodiment of the present disclosure also provides a backup SMF discovery method, including: in response to detecting the first SMF failure corresponding to the current session, sending a NF discovery request message to a network data warehouse function entity (Network Repository Function, NRF), wherein, the The NF discovery request message carries selection parameters of the first SMF, the selection parameters include an SMF group identifier and service parameters, and the SMF group identifier is the identifier of the SMF group where the first SMF is located; and receiving the NF discovery response message sent by the NRF, acquiring the information of the second SMF carried therein, and determining the standby SMF according to the information of the second SMF, wherein the NRF is based on the mapping between the information of the SMF and the selection parameters The relationship and the selection parameters determine the information of the second SMF, and wherein, the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and the SMFs in the same SMF cluster have a master-backup relationship with each other , manage the same session and are configured with the same selection parameters.

An embodiment of the present disclosure also provides a method for discovering a standby SMF, including: sending an NF registration request message to the NRF, wherein the NF registration request message carries selection parameters of the current SMF, so that the NRF can establish the information of the SMF The mapping relationship with the selection parameter, the selection parameter includes the identification and service parameters of the SMF group where the current SMF is located, and wherein the current SMF belongs to a SMF cluster in the SMF group, and the SMFs in the same SMF cluster are mutual The master-standby relationship manages the same session and is configured with the same selection parameters.

An embodiment of the present disclosure also provides an NRF, including a receiving module, an acquiring module, a discovering module, and a sending module, the receiving module is configured to receive the NF discovery request message sent by the NF, where the NF detects that the NF corresponding to the current session Sending the NF discovery request message when the first SMF fails; the obtaining module is configured to obtain the selection parameter carried in the NF discovery request message, wherein the selection parameter includes the identity and service parameters of the SMF group, and the The identification of the SMF group is the identification of the SMF group where the first SMF is located; the discovery module is used to determine the information of the second SMF corresponding to the selection parameter according to the mapping relationship between the information of the SMF and the selection parameter, wherein, The first SMF and the second SMF belong to the same SMF cluster of the same SMF group, each SMF in the same SMF cluster is in a master-backup relationship, manages the same session, and is configured with the same selection parameters; the sending module It is used to send an NF discovery response message carrying the information of the second SMF to the NF.

An embodiment of the present disclosure also provides a NF, including a sending module, a receiving module, and a determining module, the sending module is configured to send a NF discovery request message to the NRF in response to detecting a first SMF failure corresponding to the current session, wherein the The NF discovery request message carries the selection parameters of the first SMF, the selection parameters include the identification of the SMF group and the service parameters, and the identification of the SMF group is the identification of the SMF group where the first SMF is located; The receiving module is used to receive the NF discovery response message sent by the NRF; the determination module is used to obtain the information of the second SMF carried in the NF discovery response message, and determine the standby SMF according to the information of the second SMF , wherein the NRF determines the information of the second SMF according to the mapping relationship between the information of the SMF and the selection parameter and the selection parameter, and wherein the first SMF and the second SMF belong to the same SMF group In the same SMF cluster, each SMF in the same SMF cluster has a master-backup relationship, manages the same session, and is configured with the same selection parameters.

An embodiment of the present disclosure also provides an SMF, including a registration module, the registration module is configured to send a NF registration request message to the NRF, wherein the NF registration request message carries selection parameters of the current SMF, so that the NRF Establish a mapping relationship between the information of this SMF and the selection parameters, the selection parameters include the identification and service parameters of the SMF group where the current SMF is located, and wherein the current SMF belongs to a SMF cluster in the SMF group, and the SMF cluster in the same SMF cluster Each of the SMFs has a master-backup relationship with each other, manages the same session, and is configured with the same selection parameters.

An embodiment of the present disclosure also provides an electronic device, including: one or more processors;

and a storage device, on which one or more programs are stored; when the one or more programs are executed by the one or more processors, the one or more processors are made to implement the aforementioned standby SMF discovery method.

An embodiment of the present disclosure further provides a computer-readable medium on which a computer program is stored, wherein, when the program is executed by a processor, the processor is enabled to implement the method for discovering a standby SMF as described above.

Description of drawings

FIG. 1 is a schematic diagram of a system architecture provided by the present disclosure;

FIG. 2 is a schematic flow diagram of a standby SMF discovery method with NRF as the execution subject provided by the present disclosure;

FIG. 3 is a schematic flow diagram of SMF registration to NRF provided by the present disclosure;

FIG. 4 is a schematic flow diagram of a backup SMF discovery method with NF as the execution subject provided by the present disclosure;

FIG. 5 is a schematic flow diagram of a standby SMF discovery method with SMF as the execution subject provided by the present disclosure;

Fig. 6 is the signaling flowchart of the standby SMF discovery method after UPF1 detects SMF1 failure provided by the present disclosure;

Fig. 7 is the signaling flowchart of the backup SMF discovery method after the PCF detects SMF1 failure provided by the present disclosure;

FIG. 8 is a signaling flow chart of SMF registering with NRF provided by the present disclosure;

FIG. 9 is a schematic structural diagram of an NRF provided by the present disclosure;

FIG. 10 is another structural schematic diagram of NRF provided by the present disclosure;

FIG. 11 is a schematic structural diagram of the NF provided by the present disclosure;

Figure 12 is a schematic structural diagram of the SMF provided by the present disclosure; and

FIG. 13 is another structural schematic diagram of the SMF provided by the present disclosure.

detailed description

Example embodiments will be described more fully hereinafter with reference to the accompanying drawings, but may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully enable those skilled in the art to fully understand the scope of this disclosure.

As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The terminology used herein is for describing particular embodiments only and is not intended to limit the present disclosure. As used herein, the singular forms "a" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will also be understood that when the terms "comprising" and/or "consisting of" are used in this specification, it specifies the presence of said features, integers, steps, operations, elements and/or components, but does not exclude the presence or addition of One or more other features, integers, steps, operations, elements, components and/or groups thereof.

Embodiments described herein may be described with reference to plan views and/or cross-sectional views by way of idealized schematic illustrations of the present disclosure. Accordingly, the example illustrations may be modified according to manufacturing techniques and/or tolerances. Therefore, the embodiments are not limited to the ones shown in the drawings but include modifications of configurations formed based on manufacturing processes. Accordingly, the regions illustrated in the figures have schematic properties, and the shapes of the regions shown in the figures illustrate the specific shapes of the regions of the elements, but are not intended to be limiting.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art and the present disclosure, and will not be interpreted as having idealized or excessive formal meanings, Unless expressly so limited herein.

In the uRLLC dual-PDU session scenario, one SMF group includes multiple SMFs, and each NF in the SMF group is in disaster recovery for each other. The traditional standby SMF discovery scheme is as follows: two redundant PDU sessions correspond to different S-NSSAI (Single Network Slice Selection Assistance Information, single network slice selection support information) + DNN (Digital Data Network, digital data network) combination parameters , when a SMF fails, the NF obtains the information of all SMFs in the SMF group, and then further selects an appropriate standby SMF based on the S-NSSAI+DNN combination parameters of the current session. The above scheme requires at least the following two key steps: the first step is to obtain all SMF information in the SMF group where the faulty SMF is located; the second step is to select a backup SMF from all SMFs obtained in the previous step based on the combination parameters of S-NSSAI+DNN, and The process is complex and consumes a lot of resources.

To this end, the present disclosure provides a backup SMF discovery method, which can be applied to the system shown in FIG. 1 . As shown in Figure 1, the system at least includes: NRF, PCF (Policy Control Function, policy control function entity), UE, access equipment (NG-RAN, 5G access network), UPF (User Plane Function, user plane Functional entities), DN (Data Network, data network) and SMF, among which, UPF and PCF can be collectively referred to as NF, and multiple SMFs form SMF groups, and SMF groups can be divided according to ToC (for enterprises) or ToB (for individuals), There can be multiple SMF groups.

The standby SMF discovery method of the present disclosure can be applied to uRLLC double PDU session redundancy scenario, as shown in Figure 1, two redundant PDU sessions are respectively established on different SMFs in the same SMF group, wherein PDU session 1 passes UPF1 Established on SMF2, PDU session 2 is established on SMF4 through UPF2. The UE is a terminal in a vertical industry. For the same vertical industry business, the combination parameters of independent S-NSSAI+DNN can be used to trigger the establishment of two mutually redundant PDU sessions; the master (Master) NG-RAN and the auxiliary (Secondary) NG - RAN respectively serves the user plane paths of two redundant PDU sessions established by vertical industry services; UPF1 and UPF2 respectively serve the user plane paths of two redundant PDU sessions established by vertical industry services to provide data forwarding, and In the event of a SMF failure, a backup SMF for the failed SMF is found; SMF1 and SMF2 can provide session management for PDU session 1, and SMF3 and SMF4 can provide session management for another redundant PDU session (i.e., PDU session 2); NRF provides SMF registration and the SMF discovery function; the PCF is a policy and charging control decision node, and is used to discover its backup SMF when the SMF (such as SMF1) fails.

As shown in FIG. 2 , the standby SMF discovery method provided by the present disclosure includes the following steps S11 to S13.

In step S11, in response to receiving the NF discovery request message sent by the NF, the selection parameters carried in it are obtained, wherein the NF sends the NF discovery request message when detecting the failure of the first SMF corresponding to the current session, and the selection parameters include the SMF group ID and service parameters, and the ID of the SMF group is the ID of the SMF group where the first SMF belongs.

When the NF detects the failure of the first SMF corresponding to the current session, it sends an NF discovery request message carrying a selection parameter to the NRF. The selection parameter is a combination parameter composed of the identification of the SMF group and the service parameter, and the identification of the SMF group is occurrence The identifier of the SMF group where the first faulty SMF belongs. In this step, the NRF obtains the selection parameters carried in the received NF discovery request message. The NF can be UPF or PCF. UPF and PCF need to directly or indirectly interact with the SMF that manages the PDU session to implement the PDU session. Therefore, once the SMF fails, it can be detected by the UPF and PCF that manage the PDU session.

In step S12, according to the mapping relationship between the information of the SMF and the selection parameter, determine the information of the second SMF corresponding to the selection parameter, wherein the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and within the same SMF cluster Each of the SMFs has a master-backup relationship with each other, manages the same session, and is configured with the same selection parameters.

In the present disclosure, a mapping relationship between SMF information and selection parameters is established in the NRF in advance, for example, the SMF information may be an SMF identifier. An SMF group can be divided into at least one SMF cluster, and one SMF cluster includes at least two SMFs in a mutual master-backup relationship, and the SMFs in the same SMF cluster manage the same PDU session and are configured with the same selection parameters. Exemplarily, as shown in Figure 1, the SMF group includes two SMF clusters, SMF cluster 1 includes SMF1 and SMF2, SMF1 and SMF2 have a mutual master-backup relationship, SMF1 and SMF2 manage PDU session 1; SMF cluster 2 includes SMF3 and SMF4 , SMF3 and SMF4 have a master-backup relationship with each other, and SMF3 and SMF4 manage PDU session 2. Since the two redundant PDU sessions shown in FIG. 1 belong to the same SMF group, the identifiers of the SMF groups in the selection parameters of PDU session 1 and PDU session 2 are the same, but the service parameters are different.

The SMFs belonging to the same SMF cluster with a mutual master-backup relationship have the same selection parameters, and the mapping relationship between SMF information and selection parameters is established in advance. Therefore, the SMFs in the same SMF cluster correspond to the same selection parameter. In the step, the NRF can determine other standby SMFs belonging to the same SMF cluster as the first SMF by querying the mapping relationship according to the selection parameters.

In step S13, an NF discovery response message carrying the information of the second SMF is sent to the NF.

In this step, the NRF carries the information of the second SMF obtained from the query into the NF discovery response message and sends it to the NF, so that the NF determines the standby SMF according to the information of the second SMF.

According to the standby SMF discovery method provided by the present disclosure, by configuring the same selection parameters (which include the identification and service parameters of the SMF group) of the SMFs in the mutual master-backup relationship, and pre-establishing the mapping relationship between the SMF information and the selection parameters, When an SMF fails, the standby SMF of the failed SMF can be quickly determined based on the mapping relationship. It is not necessary to first obtain the information of all SMFs in the SMF group where the failed SMF is located, which simplifies the discovery process, improves system performance and discovery efficiency, and saves resources. Avoid network overload.

The alternate SMF discovery method may further include: establishing a mapping relationship between SMF information and selection parameters. The mapping relationship can be established during SMF registration. The process of establishing the mapping relationship between SMF information and selection parameters will be described in detail below in conjunction with FIG. 3 .

As shown in FIG. 3 , establishing a mapping relationship between SMF information and selection parameters includes the following steps S21 to S22.

In step S21, in response to receiving the NF registration request message sent by the SMF, the selection parameters carried therein are acquired.

In this step, SMF can realize SMF registration by sending NF registration request message (NFRegister Requset) to NRF, and NF configuration file (NFProfile) can be carried in NF registration request message, and NF configuration file can include the selection parameter of SMF, and SMF can Include the first SMF or the second SMF.

In step S22, a mapping relationship between selection parameters and SMF information is established.

In this step, for the currently registered SMF, the NRF establishes a mapping relationship between SMF information and selection parameters, and stores the mapping relationship locally. It should be noted that each SMF needs to register with NRF. Therefore, NRF can establish and store the mapping relationship between the information of each SMF and the corresponding selection parameters. In this way, when the subsequent NF initiates SMF discovery to NRF, by carrying the selection parameter parameter, the matching SMF (that is, the second SMF) can be found directly.

After setting up the mapping relationship between the information of the selection parameter and the SMF (that is, step S22), the standby SMF discovery method may also include: returning an NF registration response message (NFRegister Response) to the SMF, and carrying the NF configuration in the NF registration response message document.

The service parameter can be used to indicate the business scope that SMF can serve, for example, the service parameter can be RSN (Redundancy Sequence Number, redundancy sequence number), that is to say, the selection parameter can be the combination parameter of the mark+RSN of SMF group.

The RSN field is the field in the Nnrf interface message of NRF and the N4 interface/N7 interface message of SMF. Therefore, the RSN field of the above-mentioned various interface messages can be extended, and the combination parameter of SMF group identifier + RSN can be carried as a selection parameter In the RSN field, the transmission of the selected parameters is realized. This solution has little modification to the existing protocol and is easy to implement.

A SMF group includes at least two SMF clusters, and SMFs belonging to different SMF clusters have different selection parameters. This situation is a redundant PDU session scenario. Different SMF clusters manage a PDU session in the redundant PDU session respectively. The selection parameters of each SMF in the same SMF cluster are the same, and the selection parameters corresponding to different SMF clusters are different. The business parameters in the parameters are different (but the identification of the SMF group is the same).

In the scenario of redundant PDU sessions, according to the backup SMF discovery method provided by the present disclosure, not only can the backup SMF of the faulty SMF be quickly and easily found, but also it can be ensured that the redundant PDU sessions are still managed by different SMFs, that is, The standby SMF is not the same SMF as the SMF that manages another redundant PDU session, so as to meet the end-to-end redundancy requirements and ensure reliability. Taking Figure 1 as an example, if SMF1 fails, according to the disclosed scheme, only the standby SMF will be searched in the SMF cluster 1 where SMF1 is located, so that SMF2 can be found as the standby SMF, and PDU session 1 will be managed by SMF2, and the standby SMF will not appear as The case of the SMF within SMF cluster 2, that is, PDU session 1 will not be migrated to the SMF cluster that manages PDU2.

It should be noted that the present disclosure can also be applied to the scenario of non-redundant sessions, that is, one SMF group includes only one SMF cluster, and the PDU sessions managed by the SMFs in the SMF group do not have redundant relationship. In this scenario, according to the standby SMF discovery method provided in the present disclosure, the standby SMF of the faulty SMF can also be quickly and easily found.

In the present disclosure, when the service parameter is RSN, for vertical industry services, two redundant PDU sessions correspond to two different RSN parameter values. It should be noted that the SMFs managing the two redundant PDU sessions belong to the same SMF group. In an SMF group, for each SMF cluster, the SMF in the cluster only configures one RSN parameter value among two different RSN parameter values, so as to ensure that only one of the two redundant PDU sessions is managed, that is, mutual The SMF configurations in the master-standby relationship have the same RSN parameter value.

The present disclosure also provides a backup SMF discovery method, as shown in FIG. 4 , the backup SMF discovery method includes the following steps S31 to S32.

In step S31, in response to detecting the failure of the first SMF corresponding to the current session, a NF discovery request message is sent to the NRF, wherein the NF discovery request message carries a selection parameter of the first SMF, and the selection parameter includes the identification of the SMF group and service parameters, and the identifier of the SMF group is the identifier of the SMF group where the first SMF belongs.

In this step, if NF detects that the first SMF fails, then send to NRF the NF Discovery Request message (NFDiscovery Request) that carries the selection parameter of the first SMF, so that NRF selects parameter and the information of SMF and selection parameter Find the corresponding SMF information for the mapping relationship. It should be noted that the NF may be UPF or PCF.

In step S32, the NF discovery response message sent by the NRF is received, the information of the second SMF carried therein is obtained, and the standby SMF is determined according to the information of the second SMF, wherein the NRF is based on the mapping relationship between the information of the SMF and the selection parameters and The selection parameters determine the information of the second SMF, and wherein, the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and the SMFs in the same SMF cluster are mutually active and standby, manage the same session, and configure have the same selection parameters.

After the NRF determines the information of the SMF corresponding to the selected parameters, it returns an NF Discovery Response message (NFDiscovery Response) to the NF. In this step, the NF acquires the information of the second SMF carried in the NF discovery response message, and determines the standby SMF according to the information of the second SMF.

In the present disclosure, a mapping relationship between SMF information and selection parameters is established in the NRF in advance, for example, the SMF information may be an SMF identifier. An SMF group includes at least one SMF cluster, an SMF cluster includes at least two SMFs in a master-backup relationship, and the SMFs in the same SMF cluster manage the same PDU session and are configured with the same selection parameters. Exemplarily, as shown in Figure 1, the SMF group includes two SMF clusters, SMF cluster 1 includes SMF1 and SMF2, SMF1 and SMF2 have a mutual master-backup relationship, SMF1 and SMF2 manage PDU session 1; SMF cluster 2 includes SMF3 and SMF4 , SMF3 and SMF4 have a master-backup relationship with each other, and SMF3 and SMF4 manage PDU session 2.

SMFs belonging to the same SMF cluster with a mutual master-backup relationship have the same selection parameters, and the mapping relationship between SMF information and selection parameters is pre-established in NRF. Therefore, each SMF in the same SMF cluster corresponds to the same selection parameter. parameter, in this step, the acquired information of the second SMF is the information of other SMFs in the SMF cluster where the first SMF is located.

According to the standby SMF discovery method provided by the present disclosure, by configuring the same selection parameters (which include the identification and service parameters of the SMF group) of the SMFs in the mutual master-backup relationship, and pre-establishing the mapping relationship between the SMF information and the selection parameters, When an SMF fails, the standby SMF of the failed SMF can be quickly determined based on the mapping relationship, without first obtaining the information of all SMFs in the SMF group where the failed SMF is located, which simplifies the discovery process, improves system performance and discovery efficiency, and saves resources. Avoid network overload.

An SMF cluster includes at least two SMFs, and these SMFs can form a master-standby relationship. When a SMF cluster includes more than three SMFs, in step S32, obtain the information of a plurality of second SMFs, and these second SMFs are all SMFs with the first SMF in a master-backup relationship with each other, therefore, from multiple Select one of the second SMFs as the final backup SMF.

Correspondingly, determining the backup SMF according to the information of the second SMF (that is, step S32) may include: in response to obtaining the information of at least two second SMFs, randomly selecting a first SMF from the information of the at least two second SMFs information of the second SMF, and determine the standby SMF according to the information of the selected second SMF.

Before sending the NF discovery request message to the NRF (that is, step S31), the method may further include: receiving a selection parameter issued by the first SMF during the session establishment process.

The PDU session establishment process is as follows: UE sends a PDU session establishment request message (PDU Session Establish Request) to the first SMF, which carries the combined parameters of S-NSSAI+DNN; the first SMF sends the message to UPF and PCF respectively through different messages After the selection parameters of the first SMF, the first SMF returns a PDU session establishment response message (PDU Session Establish Response) to the UE.

Receiving the selection parameter issued by the first SMF may include: when the NF is a UPF, receiving an N4 session establishment message (N4 Session Establishment) that carries the selection parameter sent by the first SMF; when the NF is a PCF, receiving The first SMF sends a session management policy association establishment message (SM Policy Association Establishment) carrying selection parameters. The first SMF sends an N4 session establishment message to the UPF through the N4 interface to pass the selection parameters to the UPF; the first SMF sends a session management policy association establishment message to the PCF through the N7 interface to pass the selection parameters to the PCF.

After determining the standby SMF according to the information of the second SMF (that is, step S32), the standby SMF discovery method may also include: in the case that the NF is a UPF, sending an N4 session report request message (N4 Session Report Request) to the standby SMF ); in the case that the NF is a PCF, send a session management policy association modification message (SM Policy Association Modification) to the standby SMF. By sending the above message, the switching of the active and standby SMFs can be completed.

The service parameter is used to indicate the service scope that the SMF can serve. For example, the service parameter may be RSN, that is, the selection parameter may be a combined parameter of SMF group identifier+RSN.

The present disclosure also provides a backup SMF discovery method, as shown in FIG. 5 , the backup SMF discovery method includes the following step S41.

In step S41, send the NF registration request message to NRF, wherein, the selection parameter of current SMF is carried in the NF registration request message, so that NRF establishes the mapping relation between the information of this SMF and selection parameter, and selection parameter includes current SMF location The identification and service parameters of the SMF group, and wherein, the current SMF belongs to a SMF cluster in the SMF group, and each SMF in the same SMF cluster has a master-backup relationship with each other, manages the same session, and is configured with the same selection parameters.

In this step, the SMF realizes the SMF registration by sending the NF registration request message to the NRF. The NF registration request message carries the NF configuration file (NFProfile), which includes the selection parameters of the SMF, that is, the identification and service parameters of the SMF group where the SMF is located .

According to the backup SMF discovery method provided by the present disclosure, when SMF initiates registration to NRF, the selection parameters of SMF are sent to NRF, and NRF locally establishes a mapping relationship between SMF information and selection parameters. When initiating SMF discovery, you can directly find the matching SMF by carrying the selection parameters. By configuring the same selection parameters (including the identification and service parameters of the SMF group) for the SMFs in the mutual master-backup relationship, and pre-establishing the mapping relationship between the SMF information and the selection parameters, when the SMF fails, it can be based on the mapping relationship Quickly determine the backup SMF of the failed SMF, without first obtaining the information of all SMFs in the SMF group where the failed SMF is located, which simplifies the discovery process, improves system performance and discovery efficiency, saves resources, and avoids network load overload.

After sending the NF registration request message to the NRF (that is, step S41), the standby SMF discovery method may also include: receiving the NF registration response message (NFRegister Response) returned by the NRF, wherein the NF registration response message carries NF configuration file.

The standby SMF discovery method may further include: during the session establishment process, sending selection parameters to the NF in response to receiving a session establishment request message sent by the UE.

Sending the selection parameter to the NF may include: when the NF is a UPF, sending an N4 session establishment message (N4 Session Establishment) carrying the selection parameter to the UPF; when the NF is a PCF, sending a message carrying the selection parameter to the PCF The session management policy association establishment message (SM Policy Association Establishment) of the selection parameter. The SMF sends the N4 session establishment message to the UPF through the N4 interface to pass the selection parameters to the UPF, and the SMF sends the session management policy association establishment message to the PCF through the N7 interface to pass the selection parameters to the PCF.

The service parameter can be used to indicate the service scope that the SMF can serve. For example, the service parameter can be RSN, that is to say, the selection parameter can be a combined parameter of SMF group identifier+RSN.

In order to clearly describe the solution of the present disclosure, the process of UPF1 detecting a failure of SMF1 and finding a backup SMF will be described in detail below in conjunction with a specific example. FIG. 6 is a signaling flow chart of a backup SMF discovery method provided by the present disclosure after UPF1 detects a SMF1 failure. As shown in FIG. 6 , the PDU session establishment process includes the following steps S1 to S3.

In step S1, UE sends a PDU session establishment request message (PDU Session Establish Request) to SMF1, which carries the combined parameters of S-NSSAI+DNN.

In step S2, SMF1 sends N4 session establishment message (N4 Session Establishment) to UPF1, which carries selection parameters composed of SMF group identifier + RSN; SMF1 sends session management policy association establishment message (SM Policy Association Establishment) to PCF , which carries a selection parameter consisting of the SMF group ID+RSN.

In step S3, SMF1 returns a PDU session establishment response message (PDU Session Establish Response) to the UE.

As shown in Fig. 6, UPF1 detects that SMF1 fails, and executes the following steps S4 to S7.

In step S4, UPF1 sends an NF Discovery Request message (NFDiscovery Request) to NRF, which carries selection parameters composed of SMF group identifier + RSN.

In step S5, the NRF determines the SMF2 information corresponding to the selection parameter according to the mapping relationship between the SMF information and the selection parameter (SMF group identifier+RSN).

In step S6, the NRF sends an NF Discovery Response message (NFDiscovery Response) to UPF1, which carries the information of SMF2.

In step S7, UPF1 sends N4 session report request message (N4 Session Report Request) to SMF2, to complete the switching of active and standby SMF.

The process of the PCF detecting the failure of the SMF1 and discovering the standby SMF will be described in detail below in conjunction with a specific example. FIG. 7 is a signaling flow chart of a backup SMF discovery method provided by the present disclosure after the PCF detects a SMF1 failure, wherein the PDU session establishment process (steps S1 to S3 ) will not be repeated here. As shown in FIG. 7 , the PCF detects that SMF1 fails, and executes the following steps S4' to S7'.

In step S4', the PCF sends an NF Discovery Request message (NFDiscovery Request) to the NRF, which carries selection parameters consisting of the SMF group identifier + RSN.

In step S5', the NRF determines the SMF2 information corresponding to the selection parameter according to the mapping relationship between the SMF information and the selection parameter (SMF group identifier+RSN).

In step S6', the NRF sends an NF Discovery Response message (NFDiscovery Response) to the PCF, which carries the information of SMF2.

In step S7', the PCF sends a session management policy association modification message (SM Policy Association Modification) to SMF2 to complete the switching of the active and standby SMFs.

The process of registering the SMF with the NRF will be described in detail below in conjunction with a specific example. Fig. 8 is a signaling flow chart of SMF registering with NRF provided by the present disclosure. As shown in Fig. 8, the SMF registers with the NRF including the following steps S10 to S20.

In step S10, the SMF sends an NF registration request message (NFRegister Requestet) to the NRF, which carries selection parameters consisting of the SMF group identifier + RSN.

In step S20, the NRF establishes a mapping relationship between selection parameters (SMF group identifier+RSN) and SMF information.

In step S30, the NRF returns an NF registration response message (NFRegister Response) to the SMF, which carries the NF configuration file.

This disclosure can be applied to vertical industry application scenarios such as industrial application and control, remote manufacturing, remote surgery, traffic safety and control, etc. These scenarios put forward the requirements of ultra-high reliability and ultra-high and low latency. For this reason, 3GPP specifically defines uRLLC characteristics . In vertical industry scenario applications, communication reliability is improved through end-to-end session redundancy. At this time, the UE uses independent DNN+S-NSSAI to establish two redundant PDU sessions, and the two PDU sessions are connected to the There are two independent SMFs. At the same time, multiple SMFs serving vertical industries are in the same SMF group.

When the solution of the present disclosure is applied to vertical industry application scenarios (such as coal mines, electric power, industrial control, etc.), for different SMFs in an SM group, if they can serve uRLLC dual redundant PDU sessions, then refer to the current 3GPP specification Configure service parameters for it, that is, the combined parameters of the SMF group ID + RSN. In order to ensure that the dual redundant PDU session falls on two different SMFs, the two redundant PDU sessions correspond to two different RSN parameter values, and the two RSN parameter values are respectively configured on different SMFs.

When a SMF in the SMF group fails, other NFs need to reselect the SMF for the uRLLC session established on the faulty SMF. All SMFs that support this RSN can be selected directly from the SMF group where the faulty SMF is located, and then Select an SMF to replace the failed SMF. For an SMF carrying millions of vertical industry redundant PDU sessions, when it fails, if the scheme of the present disclosure is used to select a backup SMF, then each PDU session can be selected to a backup SMF in one step, which simplifies the process , which improves system performance, saves core network resources, and avoids overloading.

Based on the same technical concept, the present disclosure also provides an NRF, as shown in FIG. 9 , including a receiving module 101 , an acquiring module 102 , a discovering module 103 and a sending module 104 . The receiving module 101 is configured to receive the NF discovery request message sent by the NF, wherein the NF sends the NF discovery request message when detecting that the first SMF corresponding to the current session fails.

The acquiring module 102 is configured to acquire the selection parameters carried in the NF discovery request message, wherein the selection parameters include the identification and service parameters of the SMF group, and the identification of the SMF group is the SMF group where the first SMF is located. logo.

The discovery module 103 is configured to determine the information of the second SMF corresponding to the selection parameter according to the mapping relationship between the information of the SMF and the selection parameter, wherein the first SMF and the second SMF belong to the same SMF of the same SMF group. In an SMF cluster, each SMF in the same SMF cluster has a master-backup relationship, manages the same session, and is configured with the same selection parameters.

The sending module 104 is configured to send an NF discovery response message carrying the information of the second SMF to the NF.

As shown in Figure 10, the NRF may also include an establishment module 105, and the receiving module 101 is also used to receive the NF registration request message sent by the SMF; the obtaining module 102 is also used to obtain the selection parameter carried in the NF registration request message ; The establishment module 105 is used to establish a mapping relationship between the selection parameter and the information of the SMF.

The service parameter may be a redundant sequence number RSN.

A SMF group includes at least two SMF clusters, and SMFs belonging to different SMF clusters have different selection parameters.

The present disclosure also provides a NF, as shown in FIG. 11 , including a sending module 201 , a receiving module 202 and a determining module 203 . The sending module 201 is configured to send a NF discovery request message to the NRF in response to detecting a failure of the first SMF corresponding to the current session, wherein the NF discovery request message carries a selection parameter of the first SMF, and the selection parameter It includes the identification and service parameters of the SMF group, and the identification of the SMF group is the identification of the SMF group where the first SMF belongs.

The receiving module 202 is configured to receive the NF discovery response message sent by the NRF.

The determination module 203 is configured to obtain the information of the second SMF carried in the NF discovery response message, and determine the standby SMF according to the information of the second SMF, wherein the NRF is based on the mapping between the information of the SMF and the selection parameters The relationship and the selection parameters determine the information of the second SMF, and wherein, the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and the SMFs in the same SMF cluster have a master-backup relationship with each other , manage the same session and are configured with the same selection parameters.

The determining module 203 is further configured to, in response to the acquired information of at least two second SMFs, randomly select information of a second SMF from the information of the at least two second SMFs, and, according to the information of the selected second SMF, Identify alternate SMFs.

The receiving module 202 is also configured to receive the selection parameter issued by the first SMF during the session establishment process.

The receiving module 202 is also configured to receive the N4 session establishment message carrying the selection parameter sent by the first SMF when the NF is UPF; receive the N4 session establishment message sent by the first SMF when the NF is PCF; A session management policy association establishment message carrying the selected parameters.

The service parameter may be a redundant sequence number RSN.

The present disclosure also provides an SMF, as shown in FIG. 12 , including a registration module 301 . The registration module 301 is configured to send a NF registration request message to the NRF, wherein the NF registration request message carries the selection parameters of the current SMF, so that the NRF establishes a mapping relationship between the information of the current SMF and the selection parameters. The selection parameters include the identification and service parameters of the SMF group where the current SMF is located, and wherein the current SMF belongs to a SMF cluster in the SMF group, and each SMF in the same SMF cluster is in a master-backup relationship with each other, manages the same session, and is configured with The same selection parameters.

As shown in FIG. 13 , the SMF may further include a parameter sending module 302 . The parameter sending module 302 is configured to send the selection parameter to the NF of the session in response to receiving a session establishment request message sent by the UE during the session establishment process.

The parameter delivery module 302 is further configured to send an N4 session establishment message carrying the selection parameter to the UPF if the NF is a UPF; A session management policy association establishment message carrying the selected parameters.

The service parameter may be a redundant sequence number RSN.

The present disclosure also provides an electronic device, including: one or more processors and a storage device; wherein, one or more programs are stored on the storage device, and when the one or more programs are processed by the one or more When executed by a processor, the one or more processors implement the standby SMF discovery method according to the embodiments of the present disclosure.

The present disclosure also provides a computer-readable medium on which a computer program is stored, wherein, when the computer program is executed by a processor, the processor is enabled to realize the standby SMF discovery method according to each embodiment of the present disclosure.

Those skilled in the art can understand that all or some of the steps in the method disclosed above and the functional modules/units in the device can be implemented as software, firmware, hardware and an appropriate combination thereof. In a hardware implementation, the division between functional modules/units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component may have multiple functions, or one function or step may be composed of several physical components. Components cooperate to execute. Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit . Such software may be distributed on computer readable media, which may include computer storage media (or non-transitory media) and communication media (or transitory media). As known to those of ordinary skill in the art, the term computer storage media includes both volatile and nonvolatile media implemented in any method or technology for storage of information, such as computer readable instructions, data structures, program modules, or other data. permanent, removable and non-removable media. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disk (DVD) or other optical disk storage, magnetic cartridges, tape, magnetic disk storage or other magnetic storage devices, or can Any other medium used to store desired information and which can be accessed by a computer. In addition, as is well known to those of ordinary skill in the art, communication media typically embodies computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media .

Example embodiments have been disclosed herein, and while specific terms have been employed, they are used and should be construed in a generic descriptive sense only and not for purposes of limitation. In some instances, it will be apparent to those skilled in the art that features, characteristics and/or elements described in connection with a particular embodiment may be used alone, or may be described in combination with other embodiments, unless explicitly stated otherwise. Combinations of features and/or elements. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the scope of the present invention as set forth in the appended claims.

Claims

A method for discovering an alternate session management function entity SMF, comprising:

In response to receiving the NF discovery request message sent by the network function node NF, the selection parameters carried therein are obtained, wherein the NF sends the NF discovery request message when detecting a failure of the first SMF corresponding to the current session, and the selection parameter The parameters include the identification and service parameters of the SMF group, and the identification of the SMF group is the identification of the SMF group where the first SMF is located;

According to the mapping relationship between the information of the SMF and the selection parameter, determine the information of the second SMF corresponding to the selection parameter, wherein the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and the same SMF Each SMF in the cluster has a master-backup relationship with each other, manages the same session, and is configured with the same selection parameters; and

Sending an NF discovery response message carrying the information of the second SMF to the NF.
The method of claim 1, further comprising:

In response to receiving the NF registration request message sent by the SMF, obtain the selection parameters carried therein; and

Establish a mapping relationship between the selection parameter and the information of the SMF.
The method according to claim 1, wherein the service parameter is a redundant sequence number (RSN).
The method according to any one of claims 1 to 3, wherein one SMF group includes at least two SMF clusters, and the selection parameters of SMFs belonging to different SMF clusters are different.
An alternate SMF discovery method comprising:

In response to detecting the failure of the first SMF corresponding to the current session, sending a NF discovery request message to the network data warehouse functional entity NRF, wherein the NF discovery request message carries a selection parameter of the first SMF, and the selection parameter Including the identification and service parameters of the SMF group, and the identification of the SMF group is the identification of the SMF group where the first SMF is located; and

receiving the NF discovery response message sent by the NRF, acquiring the information of the second SMF carried therein, and determining the standby SMF according to the information of the second SMF, wherein the NRF is based on the mapping between the information of the SMF and the selection parameters relationship and said selection parameters determine information about said second SMF,

Wherein, the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and the SMFs in the same SMF cluster have a master-backup relationship with each other, manage the same session, and are configured with the same selection parameters.
The method according to claim 5, wherein determining the standby SMF according to the information of the second SMF comprises:

In response to acquiring the information of at least two second SMFs, randomly select information of a second SMF from the information of the at least two second SMFs, and determine a standby SMF according to the information of the selected second SMF.
The method according to claim 5, wherein, before sending the NF discovery request message to the NRF, the method further comprises:

During the session establishment process, the selection parameter delivered by the first SMF is received.
The method according to claim 7, wherein receiving the selection parameter issued by the first SMF comprises:

When the current NF is a user plane functional entity UPF, receive an N4 session establishment message carrying the selection parameter sent by the first SMF;

In the case that the current NF is a policy control function entity PCF, receiving a session management policy association establishment message carrying the selection parameter sent by the first SMF.
The method according to claim 5, wherein the service parameter is a redundant sequence number (RSN).
The method according to any one of claims 5 to 9, wherein one SMF group includes at least two SMF clusters, and the selection parameters of SMFs belonging to different SMF clusters are different.
An alternate SMF discovery method comprising:

Sending a NF registration request message to the NRF, wherein the NF registration request message carries selection parameters of the current SMF, so that the NRF establishes a mapping relationship between the information of the current SMF and the selection parameters, and the selection parameters include The identification and business parameters of the SMF group where the current SMF belongs,

Wherein, the current SMF belongs to an SMF cluster in the SMF group, and the SMFs in the same SMF cluster have a master-backup relationship with each other, manage the same session, and are configured with the same selection parameters.
The method of claim 11, further comprising:

During the session establishment process, in response to receiving a session establishment request message sent by the user equipment, the selection parameter is delivered to the NF of the session.
The method according to claim 12, wherein the delivering the selection parameter to the NF of the session comprises:

When the NF is a UPF, sending an N4 session establishment message carrying the selection parameter to the UPF;

If the NF is a PCF, send a session management policy association establishment message carrying the selection parameter to the PCF.
The method according to claim 11, wherein the service parameter is a redundant sequence number (RSN).
The method according to any one of claims 11 to 14, wherein one SMF group includes at least two SMF clusters, and the selection parameters of SMFs belonging to different SMF clusters are different.
A network data warehouse functional entity NRF, including a receiving module, an acquisition module, a discovery module and a sending module,

The receiving module is used to receive the NF discovery request message sent by the network function node NF, wherein the NF sends the NF discovery request message when detecting that the first session management function entity SMF corresponding to the current session fails;

The obtaining module is used to obtain the selection parameters carried in the NF discovery request message, wherein the selection parameters include the identification of the SMF group and service parameters, and the identification of the SMF group is the SMF group where the first SMF belongs logo;

The discovery module is configured to determine the information of the second SMF corresponding to the selection parameter according to the mapping relationship between the information of the SMF and the selection parameter, wherein the first SMF and the second SMF belong to the same SMF group In the same SMF cluster, each SMF in the same SMF cluster has a master-backup relationship, manages the same session, and is configured with the same selection parameters;

The sending module is configured to send an NF discovery response message carrying the information of the second SMF to the NF.
A network function node NF, including a sending module, a receiving module and a determining module,

The sending module is configured to send a NF discovery request message to the network data warehouse function entity NRF in response to detecting a failure of the first session management function entity SMF corresponding to the current session, wherein the NF discovery request message carries the first session management function entity SMF. A selection parameter of an SMF, the selection parameter including the identification and service parameters of the SMF group, and the identification of the SMF group is the identification of the SMF group where the first SMF is located;

The receiving module is configured to receive the NF discovery response message sent by the NRF;

The determination module is configured to acquire the information of the second SMF carried in the NF discovery response message, and determine the standby SMF according to the information of the second SMF, wherein the NRF is based on the information of the SMF and the selection parameter The mapping relationship and the selection parameters determine the information of the second SMF, and wherein the first SMF and the second SMF belong to the same SMF cluster of the same SMF group, and the SMFs in the same SMF cluster are mutually active and standby relationship, manage the same session, and are configured with the same selection parameters.
A session management function entity SMF, including a registration module,

The registration module is configured to send a network function node NF registration request message to the network data warehouse functional entity NRF, wherein the NF registration request message carries selection parameters of the current SMF, so that the NRF establishes the current SMF information and Select a mapping relationship between parameters, and the selection parameters include the identification and service parameters of the SMF group where the current SMF is located,

Wherein, the current SMF belongs to an SMF cluster in the SMF group, and the SMFs in the same SMF cluster have a master-backup relationship with each other, manage the same session, and are configured with the same selection parameters.
An electronic device comprising:

one or more processors; and

a storage device having one or more programs stored thereon;

When the one or more programs are executed by the one or more processors, the one or more processors are made to implement the standby SMF discovery method according to any one of claims 1 to 15.
A computer-readable medium, on which a computer program is stored, wherein, when the program is executed by a processor, the processor is made to implement the standby SMF discovery method according to any one of claims 1 to 15.