Session management function entity discovery method, network function node, access and mobility management function entity, electronic device and computer-readable storage medium

Abstract

The present disclosure is intended to disclose a method for discovering a session management function entity (SMF) applied to a session creation process, comprising: determining a set of SMFs in response to the reception of a first request message transmitted by an access and mobility management function entity (AMF), wherein the SMF in the set of SMFs is an SMF to which a virtual network (VN) group to which a user device (UE) requesting session creation by accessing the AMF is subscribed belongs; and determining a priority SMF of the VN group and transmitting information of the priority SMF to the AMF, wherein the priority SMF is one of the SMFs in the set of SMFs; and the present disclosure is also intended to provide a network function node, an access and mobility management function entity, an electronic device, and a computer-readable storage device.

Description

Technology Field

[0001] Cross-reference with related applications

[0002] This application requests priority to Chinese patent application No. 202110760119.9 filed on July 6, 2021, and incorporates the contents of said Chinese patent application into this application.

[0003] Technology field

[0004] This disclosure relates to the field of communication technology, specifically to a method for discovering a session management function entity, a network function node, an access and mobility management function entity, an electronic device, and a computer-readable storage medium. Background Technology

[0005] 3GPP (3rd Generation Partnership Project) version R16 introduced support for 5G (The 5th Generation Mobile Communications) LAN (Local Area Network) services, providing services similar to private LAN communication. Users under the same 5G LAN form a single 5G VN (Virtual Network) group, and each 5G VN group is assigned a single 5G VN group ID.

[0006] Conventional 3GPP standards require that the same 5G VN group belong to only one Session Management Function (SMF), but this restriction leads to a problem of reduced communication reliability. For example, if a failure occurs in the SMF to which the 5G VN group belongs, communication for users within the said 5G VN group may become impossible. Therefore, to ensure the availability of 5G LAN networks, the same 5G VN group is made to belong to multiple SMFs during actual deployment. However, when the same 5G VN group belongs to multiple SMFs, there are problems with relatively large time delays and network loads because the User Equipment (UE) on both sides of the communication perform data routing and transmission through two different Anchor User Plane Functions (A-UPFs).

[0007] In the first aspect, embodiments of the present disclosure are intended to provide a method for discovering session management function entities (SMFs) applied to a session creation process, wherein

[0008] In response to the reception of a first request message transmitted by an Access and Mobility Management Function Entity (AMF), a set of Session Management Function Entities (SMF) is determined, wherein the SMF among the set of SMFs is an SMF to which the Virtual Network (VN) group to which the user device requesting session creation by accessing the AMF belongs is joined;

[0009] Determine the priority SMF of the above VN group, wherein the priority SMF is one SMF among the above SMF set; and,

[0010] The information of the above priority SMF is transmitted to the above AMF.

[0011] In another aspect, embodiments of the present disclosure are also intended to provide an SMF discovery method applicable to a session creation process,

[0012] In response to the reception of a Session Management Function Entity (SMF) discovery request message transmitted by an Access and Mobility Management Function Entity (AMF), information on a Virtual Network (VN) group included in the said SMF discovery request message is obtained;

[0013] Based on the information of the above VN group and the second matching relationship between the information of the VN group and the information of the SMF, the set of SMFs of the above VN group is determined; and,

[0014] An SMF discovery response message containing the set of SMFs is transmitted to the above AMF, causing the above AMF to initiate a priority SMF selection request.

[0015] In another aspect, embodiments of the present disclosure are also intended to provide a method for discovering SMF,

[0016] In response to the reception of a session creation request message transmitted by a user device (UE), a first request message is transmitted to a network function node (NF), wherein the first request message is configured to indicate the NF to determine the priority SMF of the virtual communication network (VN) group to which the UE belongs, and the priority SMF is one of the SMFs in the set of SMFs, and the SMF in the set of SMFs is the SMF to which the VN group belongs;

[0017] Receive information of the priority SMF transmitted by the above NF; and,

[0018] A session creation request message is sent to the priority SMF corresponding to the information of the above priority SMF.

[0019] In another aspect, embodiments of the present disclosure also provide a network function node comprising a first processing module, an SMF discovery module, and a transmission module, wherein the first processing module determines a set of session management function entities (SMFs) in response to the reception of a first request message transmitted by an access and mobility management function entity (AMF), wherein the SMFs in the set of SMFs are configured to be SMFs to which the virtual network (VN) group to which the user device requesting session creation by accessing the AMFs belongs is joined;

[0020] The above SMF discovery module is configured to determine the priority SMF of the VN group, wherein the priority SMF is one of the SMF sets; and,

[0021] The above transmission module is configured to transmit information of the above priority SMF to the above AMF.

[0022] In another aspect, an embodiment of the present disclosure is also for providing a network function node comprising a receiving module, an acquisition module, a processing module, and a transmitting module, wherein the receiving module is configured to receive a Session Management Function Entity (SMF) discovery request message transmitted by an Access and Mobility Management Function Entity (AMF);

[0023] The above acquisition module is configured to acquire information about a virtual network (VN) group included in the above SMF discovery request message;

[0024] The above processing module is configured to determine the set of SMFs of the VN group according to the information of the VN group and the second matching relationship between the information of the VN group and the information of the SMF; and,

[0025] The transmission module is configured to transmit an SMF discovery response message containing the set of SMFs to the AMF, so that the AMF initiates a priority SMF selection request.

[0026] In another aspect, an embodiment of the present disclosure is also configured to provide an access and mobility management function entity, comprising an SMF discovery module, wherein the SMF discovery module transmits a first request message to a network function node (NF) in response to the reception of a session creation request message transmitted by a user device (UE), wherein the first request message is configured to indicate the NF to determine the priority SMF of a virtual network (VN) group to which the UE belongs, wherein the priority SMF is one of the SMFs in the set of SMFs, and the SMF in the set of SMFs is the SMF to which the VN group belongs; and wherein the NF receives information of the priority SMF transmitted by the NF and transmits a session creation request message to the priority SMF corresponding to the information of the priority SMF.

[0027] In another aspect, embodiments of the present disclosure are also intended for use in electronic devices,

[0028] At least one processor; and,

[0029] A storage device having at least one computer program stored therein; comprising,

[0030] When the above at least one computer program is executed by the above at least one processor, the above at least one processor is configured to implement the above SMF discovery method.

[0031] In another aspect, embodiments of the present disclosure also provide a computer-readable storage medium in which a computer program is stored and configured to implement the SMF discovery method as described above when said computer program is executed by a processor. Brief explanation of the drawing

[0032] FIGS. 1a to 1c are exemplary diagrams of three methods of data routing and transmission between user devices under a 5G local area network (LAN) provided in an embodiment of the present disclosure; FIG. 2 is a flowchart illustrating a method for discovering a session management function entity (SMF) with a network function node (NF) as the executing entity, provided in an embodiment of the present disclosure; FIG. 3 is an example flowchart of SMF registration provided in an embodiment of the present disclosure; FIG. 4 is a flowchart illustrating an example of an SMF discovery method having a Group Management Function Entity (GMF) as the executing entity, provided in an embodiment of the present disclosure; FIG. 5 is a flowchart illustrating an example of an SMF discovery method having an Access and Mobility Management Function Entity (AMF) as the executing entity, provided in an embodiment of the present disclosure; FIG. 6 is an example flowchart of AMF re-erecting the session creation process provided in an embodiment of the present disclosure; FIG. 7 is a signaling flowchart of an SMF discovery method for deploying a GMF and a priority SMF selection function entity (GPSSF) under different NF environments, provided in an embodiment of the present disclosure; FIG. 8 is a signaling flowchart of an SMF discovery method for distributing GMF and GPSSF under the same NF environment, provided in an embodiment of the present disclosure; FIG. 9 is an example diagram of a signaling flow for registering an SMF as an NF to which a GMF is distributed, provided in an embodiment of the present disclosure; FIGS. 10 to 12 are exemplary structural diagrams of NF provided in embodiments of the present disclosure; FIGS. 13 and 14 are exemplary structural diagrams of an NF (NF with GMF distributed thereon) provided in an embodiment of the present disclosure; FIGS. 15 and 16 are exemplary structural diagrams of an AMF provided in an embodiment of the present disclosure. Specific details for implementing the invention

[0033] Exemplary embodiments will be described in more detail below with reference to the drawings; however, the illustrated exemplary embodiments may be implemented in other forms, and this disclosure should not be interpreted as being limited by the embodiments described herein. The following embodiments are provided to make this disclosure clearer and more complete, and to enable those skilled in the art to more fully understand the scope of this disclosure.

[0034] The term "and / or" as used in the text includes any and all combinations of one or more of the related listed items.

[0035] The terms used herein are for describing specific embodiments only and are not intended to limit this disclosure. Unless otherwise indicated in the context, the singular forms “one” and “above” used herein include the plural forms. Where the terms “comprising” and / or “...consisting of” are used in this specification, they mean only that certain features, compositions, steps, operations, elements, and / or elements are present, and do not preclude that one or more other features, compositions, steps, operations, elements, elements, and / or combinations thereof may be present or added.

[0036] The embodiments described in the text may be described with reference to plan views and / or cross-sectional views in accordance with the preferred exemplary drawings of this disclosure. Accordingly, exemplary drawings may be modified according to manufacturing technology and / or tolerances. Accordingly, the embodiments are not limited to the embodiments illustrated in the drawings, but also include modifications of configurations formed based on the manufacturing process. Accordingly, the areas illustrated in the drawings are merely illustrative, and the shapes of the areas illustrated in the drawings are examples of specific shapes of the areas of the device, but are not limiting.

[0037] Unless otherwise defined, all terms used in this text (including technical and scientific terms) shall have the same meaning as generally understood by those skilled in the art. Furthermore, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and the present invention, and unless explicitly defined in this text, it is desirable not to interpret them in an ideal or overly formal sense.

[0038] Under the same 5th Generation Mobile Communications (5G) Virtual Network (VN) group, communication data between users may be locally routed through an Anchor User Plane Function (A-UPF), routed through an N19 interface between two A-UPFs, or routed through a Data Network (DN) via an N6 interface between two A-UPFs, and the method used is determined by the relationship between the User Equipment (UE) of both communicating parties and the A-UPF. As shown in FIG. 1a, when both communicating parties (UE1 and UE2) belong to the same A-UPF, data transmission is performed directly through the local routing of the A-UPF; As shown in FIG. 1b, if the two communication parties (UE1 and UE2) belong to different A-UPFs and the A-UPF supports the N19 interface, data routing and delivery are performed based on the N19 interface; as shown in FIG. 1c, if the two communication parties (UE1 and UE2) belong to different A-UPFs and the A-UPF does not support the N19 interface, data routing and delivery are performed through the DN based on the N6 interface.

[0039] As can be seen from the three communication data routing architectures of the 5G LAN (Local Area Network) mentioned above, local routing based on A-UPF does not require a separate N19 or N6 interface for data routing and delivery, so it offers the lowest transmission time latency and can simultaneously reduce network load. Based on these characteristics, the 3GPP standard requires that Protocol Data Unit (PDU) sessions of users within the same 5G VN group belong to the same Session Management Function (SMF) entity, and for PDU sessions within the same 5G VN group, the SMF selects the same A-UPF whenever possible. However, this restriction leads to a problem of reduced communication reliability. For example, if a failure occurs in the SMF to which the 5G VN group belongs, communication among users within the 5G VN group becomes impossible. Therefore, to ensure the reliability of 5G LAN networks, the same 5G VN group is made to belong to multiple SMFs during actual deployment. However, since current 3GPP standards cannot ensure that PDU sessions under the same 5G VN group select the same SMF, the advantages of local routing under 5G LAN services cannot be utilized.

[0040] The embodiments of this disclosure are intended to provide a method for discovering SMFs. When the same 5G VN group belongs to multiple SMFs, when a user under the 5G VN group creates a PDU session, the Access and Mobility Management Function (AMF) entity selects and accesses the same SMF, that is, the AMF selects the same SMF for the PDU session of the same 5G VN group. The embodiments of this disclosure describe the creation of a PDU session in a 5G environment as an example.

[0041] As illustrated in FIG. 2, the SMF discovery method applied to the session creation process provided in the embodiment of the present disclosure includes steps 11 to 13.

[0042] In step 11, in response to the reception of the first request message transmitted by the AMF, the set of SMFs is determined, wherein the SMFs in the set of SMFs are SMFs to which the VN group to which the UE requesting session creation by accessing the AMF belongs is joined.

[0043] A single VN group includes multiple UEs, and if a PDU session is to be performed between UEs within the same VN group, they must first be registered on an AMF. UEs within the same VN group may be registered on the same AMF or on different AMFs, and a PDU session can be created only after the UE has completed registration on the AMF. After a UE in the VN group has completed AMF registration, if it wishes to communicate with another UE within the VN group, it sends a PDU session creation request message to the registered AMF, and after the AMF receives the PDU session creation request message, it sends a first request message to the NF (Network Function Node).

[0044] In this step, the NF receives a first request message transmitted by the AMF and then determines the set of SMFs through the first request message. The set of SMFs consists of at least two SMFs, and the SMFs are SMFs to which the VN group to which the UE that accessed the AMF and requested the creation of a PDU session belongs is joined.

[0045] The Group Management Function (GMF) is intended to manage information about VN groups, and the Group Preferred SMF Selection Function (GFSF) is intended to select a preferred SMF from a set of SMFs (i.e., a set of SMFs) to which the VN groups belong. It should be specifically explained that the GMF and GPSSF can be deployed independently on different NFs, or they can be deployed simultaneously on the same NF, and the GMF and GPSSF can be a single functional element of a conventional NF or a new NF. When the types and function settings of the NFs are different, the corresponding first request messages are also different, and the first request messages and processing flows for different NF types and function settings will be explained in detail in the following content.

[0046] In step 12, the priority SMF of the VN group is determined, and the priority SMF is one of the SMFs in the set of SMFs.

[0047] In this step, the NF determines the priority SMF of the VN group, wherein the priority SMF is one of the SMFs in the set of SMFs. The priority SMF refers to the SMF that the AMF accesses preferentially; in a PDU session initiated by a UE within the VN group, the AMF accesses the priority SMF preferentially and transmits a request to create a PDU session to the priority SMF. It should be specifically noted that once the priority SMF is determined, no change typically occurs in order to ensure that the AMF selects and accesses the same SMF for the PDU session of the same 5G VN group, unless a failure occurs in the priority SMF.

[0048] In step 13, first, the information of the SMF is transmitted to the AMF.

[0049] In this step, if the type and function settings of the NF are different, the priority SMF determined through step 12 is transmitted to the AMF through a different message so that the AMF accesses the priority SMF and creates a PDU session.

[0050] An embodiment of the present disclosure is intended to provide a method for discovering SMFs applicable to a session creation process, wherein, in response to the reception of a first request message transmitted by an AMF, a set of SMFs is determined, wherein the SMF in the set of SMFs is an SMF to which the VN group to which the UE requesting session creation by accessing the AMF belongs is joined; a priority SMF of the VN group is determined, and information of the priority SMF is transmitted to the AMF, wherein the priority SMF is one of the SMFs in the set of SMFs; The SMF discovery method provided in the embodiment of the present disclosure selects one priority SMF from the set of SMFs to which the VN group to which the UE belongs, and when creating a session, the AMF accesses the priority SMF and initiates a session creation request, thereby enabling all AMFs to access the same SMF as much as possible regardless of whether the UEs within the VN group have accessed different AMFs or the same AMF, that is, by performing local routing delivery directly through A-UPF between each UE under the same VN group, the reliability of network communication can be ensured, while simultaneously reducing communication time delay and network load.

[0051] In some embodiments, the SMF discovery method further includes the step of obtaining information of the VN group included in the first request message after receiving the first request message transmitted by the AMF and before determining the priority SMF of the VN group.

[0052] In some embodiments, the determination of the priority SMF of the VN group (i.e., step 12) includes the step of using the determined priority SMF as the priority SMF of the VN group in response to the case where the priority SMF corresponding to the information of the VN group is determined according to the first mapping relationship between the information of the VN group and the information of the priority SMF; and the step of selecting one SMF from the set of SMFs and using it as the priority SMF of the VN group in response to the case where the priority SMF corresponding to the information of the VN group is not determined according to the first mapping relationship between the information of the VN group and the information of the priority SMF.

[0053] In the NF, a first mapping relationship between the information of the VN group and the information of the priority SMF is stored, and if the priority SMF can be determined according to the first mapping relationship, it means that the NF has previously selected a priority SMF for the VN group (i.e., the priority SMF of the VN group already exists). If, during the process of creating a PDU session, it is discovered that the priority SMF of the VN group already exists in the NF, then in step 12, there is no need to determine the priority SMF again, and the previously determined priority SMF is used as the priority SMF of the VN group; if it is discovered that the priority SMF of the VN group does not exist in the NF, then in step 12, the priority SMF is determined, that is, one SMF is selected from the set of SMFs and made the priority SMF of the VN group.

[0054] In some embodiments, selecting one SMF from the set of SMFs to use as the priority SMF for the VN group includes the step of using a pre-designated SMF from the set of SMFs as the priority SMF for the VN group, or randomly selecting one SMF from the set of SMFs to use as the priority SMF for the VN group. In other words, the priority SMF can be determined by a static setting method, or the priority SMF can be determined by a dynamic selection method. In the static setting method, one SMF from the set of SMFs can be pre-designated as the priority SMF using a setting file or setting parameters, and in the dynamic selection method, one SMF can be randomly selected from the set of SMFs to use as the priority SMF.

[0055] In order to ensure that the AMF selects and accesses the same SMF for the PDU session of the same 5G VN group, the priority SMF of the VN group is determined first, and then the information of the priority SMF is recorded during the NF. Accordingly, in some embodiments, the SMF discovery method also creates a first mapping relationship between the information of the VN group and the information of the priority SMF after selecting one SMF from the set of SMFs and using it as the priority SMF of the VN group. By creating a first mapping relationship between the information of the VN group and the information of the priority SMF, the existence of a priority SMF corresponding to the VN group during the NF can be determined by querying the first mapping relationship. If the first mapping relationship is queried, the information of the priority SMF can be obtained directly, and if the first mapping relationship is not queried, one priority SMF can be selected for the VN group. Since there is no need to perform the selection of the priority SMF every time, the processing of the NF can be simplified and the priority SMF can be ensured not to change.

[0056] Below, the process of determining the first request message and the SMF set will be explained separately, with respect to the different types and function settings of NFs.

[0057] In some embodiments, GMF and GPSSF are distributed simultaneously during NF, and the first request message is an SMF discovery request message, and the SMF discovery method further includes the step of obtaining information of a VN group included in the SMF discovery request message after receiving the first request message transmitted by the AMF. In some embodiments, determining the SMF set includes determining the SMF set of the VN group according to the second mapping relationship between the information of the VN group and the information of the SMF. Since the information of the VN group and the second mapping relationship between the information of the VN group and the information of the SMF are recorded in the GMF, the SMF set can be obtained by determining the information of all SMFs corresponding to the VN group according to the second mapping relationship during the process of determining the SMF set.

[0058] In some embodiments, the SMF discovery request message may further include at least one of UE location information, DNN (Data Network Name), and network slice information. When determining the SMF set, the information of the VN group and at least one of the information included in the SMF discovery request message may be combined and used as a determining element for the SMF set.

[0059] In the case where GMF and GPSSF are simultaneously distributed during NF, in some embodiments, transmitting the information of the priority SMF to the AMF (i.e., step 13) may include transmitting an SMF discovery response message to the AMF, wherein the SMF discovery response message includes the information of the priority SMF. In this step, when the NF in which GMF and GPSSF are simultaneously distributed transmits an SMF discovery response message to the AMF, the information of the priority SMF is included in the SMF discovery response message.

[0060] In some embodiments, as the SMF discovery response message may further include a set of SMFs, if the AMF subsequently fails to initiate a PDU session creation request to the priority SMF, the AMF may select another SMF from the set of SMFs and initiate a PDU session creation request again.

[0061] In some embodiments, when the GMF and GPSSF are each distributed in different NFs, the first request message is a VN group priority SMF selection request message, and determining the SMF set includes the step of obtaining the SMF set included in the VN group priority SMF selection request message, wherein the SMF set is determined by the second mapping relationship between the information of the VN group and the information of the SMF and the information of the VN group included in the SMF discovery request message transmitted by the AMF, and transmitting the obtained SMF set to the AMF. In other words, in an environment where the GMF and GPSSF are each distributed in different NFs, the AMF first transmits an SMF discovery request message containing the information of the VN group to the NF where the GMF is distributed (e.g., NF1), and NF1 determines the SMF set corresponding to the information of the VN group through the second mapping relationship between the information of the VN group and the information of the SMF, and returns an SMF discovery response message containing the SMF set to the AMF. AMF sends a VN group priority SMF selection request message containing the above SMF set to an NF (e.g., NF2) to which GPSSF is distributed, and NF2 directly obtains the SMF set from among the VN group priority SMF selection request messages.

[0062] In an environment where the GMF and GPSSF are each deployed in different NFs, in some embodiments, transmitting the information of the priority SMF to the AMF (i.e., step 13) includes transmitting a VN group priority SMF selection response message containing the information of the priority SMF to the AMF. In this step, the NF2 in which the GPSSF is deployed returns the VN group priority SMF selection response message to the AMF, wherein the VN group SMF selection response message includes the information of the priority SMF.

[0063] In some embodiments, the SMF discovery method further includes the step of creating a second mapping relationship between the information of the VN group and the information of the SMF, wherein the second mapping relationship is created at the time of registration of the SMF, and the process of creating the second mapping relationship between the information of the VN group and the information of the SMF will be explained in detail below with reference to FIG. 3.

[0064] As illustrated in FIG. 3, generating a second mapping relationship between the information of the VN group and the information of the SMF includes steps 21 and 22.

[0065] In step 21, in response to the reception of an SMF registration request message transmitted by the SMF, information about the VN group included in the SMF registration request message is obtained.

[0066] In this step, the SMF transmits an SMF registration request message to an NF in which the GMF is distributed (which may be an NF in which the GMF is distributed alone, or an NF in which the GMF and GPSSF are distributed simultaneously) to realize SMF registration, wherein the SMF registration request message includes information of a VN group corresponding to the SMF.

[0067] In step 22, a second mapping relationship is created between the information of the VN group and the information of the SMF.

[0068] In this step, for the currently registered SMF, the NF in which the GMF is distributed creates a second mapping relationship between the information of the VN group and the information of the SMF, and stores the second mapping relationship locally. It must be specifically explained that since each SMF must be registered in the NF in which the GMF is distributed, the NF in which the GMF is distributed can create and store a second mapping relationship between the information of each SMF and the information of the corresponding VN group, and accordingly, when determining the set of SMFs thereafter, the set of SMFs can be obtained by directly obtaining the information of all SMFs of the VN group through the information of the VN group and the second mapping relationship.

[0069] In some embodiments, the SMF discovery method may further include the step of returning a registration response message to the SMF after creating a second mapping relationship between the information of the VN group and the information of the SMF (i.e., step 22).

[0070] An embodiment of the present disclosure is also intended to provide a method for discovering SMF, and as illustrated in FIG. 4, the method for discovering SMF comprises steps 31 to 33.

[0071] In step 31, in response to the reception of the SMF discovery request message transmitted by the AMF, information about the VN group included in the SMF discovery request message is obtained.

[0072] In this step, the NF to which the GMF is distributed receives an SMF discovery request message transmitted by the AMF, and obtains information about the VN group included in the SMF discovery request message.

[0073] In step 32, the set of SMFs of the VN group is determined according to the second matching relationship between the information of the VN group and the information of the SMF.

[0074] Since the information of the VN group and the second mapping relationship between the information of the VN group and the information of the SMF are recorded in the NF in which the GMF is distributed, in this step, the SMF set can be obtained by determining the information of all SMFs corresponding to the VN group according to the second mapping relationship.

[0075] In step 33, an SMF discovery response message containing the SMF set is sent to the AMF to induce the AMF to initiate a priority SMF selection request.

[0076] An SMF discovery method applied to a session creation process provided in an embodiment of the present disclosure acquires information of a virtual network VN group included in an SMF discovery request message as a response to the reception of an SMF discovery request message transmitted by an AMF; determines a set of SMFs of a VN group according to the information of the VN group and a second mapping relationship between the information of the VN group and the information of the SMF; and transmits an SMF discovery response message containing the set of SMFs to the AMF so that the AMF initiates a priority SMF selection request. The SMF discovery method provided in the embodiment of the present disclosure selects one priority SMF from the set of SMFs to which the VN group to which the UE belongs, and when creating a session, the AMF accesses the priority SMF and initiates a session creation request, thereby enabling all AMFs to access the same SMF as much as possible regardless of whether the UEs within the VN group have accessed different AMFs or the same AMF, that is, by performing local routing delivery directly through A-UPF between each UE under the same VN group, the reliability of network communication can be ensured, while simultaneously reducing communication time delay and network load.

[0077] In some embodiments, the SMF discovery method further comprises the step of creating a second mapping relationship between the information of the VN group and the information of the SMF, wherein the second mapping relationship is created at the time of registration of the SMF, and as illustrated in FIG. 3, creating the second mapping relationship between the information of the VN group and the information of the SMF includes steps 21 and 22.

[0078] In step 21, in response to the reception of an SMF registration request message transmitted by the SMF, information about the VN group included in the SMF registration request message is obtained.

[0079] In this step, the SMF transmits an SMF registration request message to an NF in which the GMF is distributed (which may be an NF in which the GMF is distributed alone, or an NF in which the GMF and GPSSF are distributed simultaneously) to realize SMF registration, wherein the SMF registration request message includes information of a VN group corresponding to the SMF.

[0080] In step 22, a second mapping relationship is created between the information of the VN group and the information of the SMF.

[0081] In this step, for the currently registered SMF, the NF in which the GMF is distributed creates a second mapping relationship between the information of the VN group and the information of the SMF, and stores the second mapping relationship locally. It must be specifically explained that since each SMF must be registered in the NF in which the GMF is distributed, the NF in which the GMF is distributed can create and store a second mapping relationship between the information of each SMF and the information of the corresponding VN group, and accordingly, when determining the set of SMFs thereafter, the set of SMFs can be obtained by directly obtaining the information of all SMFs of the VN group through the information of the VN group and the second mapping relationship.

[0082] In some embodiments, the SMF discovery method may further include the step of returning a registration response message to the SMF after creating a second mapping relationship between the information of the VN group and the information of the SMF (i.e., step 22).

[0083] An embodiment of the present disclosure is also intended to provide a method for discovering SMF, and as illustrated in FIG. 5, the method for discovering SMF comprises steps 41 to 43.

[0084] In step 41, in response to the reception of a session creation request message transmitted by the UE, a first request message is transmitted to the NF, wherein the first request message is configured to determine the priority SMF of the VN group to which the UE is joined by indicating the NF, and the priority SMF is one of the SMFs in the set of SMFs, and the SMF in the set of SMFs is the SMF to which the VN group belongs.

[0085] A single VN group includes multiple UEs, and if a PDU session is to be performed between UEs within the same VN group, they must first be registered on an AMF. UEs within the same VN group may be registered on the same AMF or on different AMFs, and a PDU session can be created only after the UE has completed registration on the AMF. If a UE in the VN group wishes to communicate with another UE within the VN group after completing AMF registration, it sends a PDU session creation request message to the registered AMF. After receiving the PDU session creation request message, the AMF sends a first request message to the NF, so that the NF determines the priority SMF of the VN group to which the UE belongs, wherein the priority SMF is the first SMF in the set of SMFs, and the SMF in the set of SMFs is the SMF to which the VN group belongs.

[0086] When the types and function settings of NFs are different, the first request message is also different, and in the following content, the first request message and processing flow for different NF types and function settings will be explained in detail.

[0087] In step 42, the information of the priority SMF transmitted by NF is received.

[0088] In this step, if the type and function settings of the NF are different, the AMF receives information of the priority SMF transmitted by the NF of the corresponding type and function settings through different messages.

[0089] In step 43, a session creation request message is first sent to the priority SMF corresponding to the information of the SMF.

[0090] The SMF discovery method applied to the session creation process provided in the embodiment of the present disclosure is configured to transmit a first request message to an NF in response to the reception of a session creation request message transmitted by a UE, wherein the first request message is configured to determine the priority SMF of the VN group to which the UE is joined by indicating the NF, and the priority SMF is one SMF among the set of SMFs, and the SMF among the set of SMFs is the SMF to which the VN group belongs; the SMF discovery method provided in the embodiment of the present disclosure selects one priority SMF from the set of SMFs to which the VN group to which the UE is joined belongs, and when creating a session, causes the AMF to access the priority SMF and initiate a session creation request, thereby enabling all AMFs to access the same SMF regardless of whether UEs within the VN group have accessed different AMFs or the same AMF, that is, by performing local routing delivery directly through A-UPF between each UE under the same VN group, thereby ensuring the reliability of network communication, while simultaneously lowering communication time delay and reducing network load.

[0091] In some embodiments, the SMF discovery method further includes the step of acquiring a set of SMFs before sending a session creation request message to a priority SMF corresponding to the information of the priority SMF (i.e., step 43).

[0092] In some embodiments, as illustrated in FIG. 6, after first sending a session creation request message to an SMF corresponding to the information of the SMF (i.e., step 43), the SMF discovery method further includes steps 44 and 45.

[0093] In step 44, in response to the reception of a session creation request failure message transmitted by the SMF, other SMFs other than the SMF are selected from the set of SMFs.

[0094] First, if the SMF fails to create a PDU session, it returns a message indicating the failure of the PDU session creation request to the AMF. After receiving the message indicating the failure of the PDU session creation request transmitted by the SMF, the AMF selects another SMF (i.e., a replacement SMF) from the set of SMFs according to a local policy and may initiate a request to create a PDU session to the replacement SMF. The local policy may pre-designate the replacement SMF or randomly select the replacement SMF; specifically, the local policy may define whether to select the replacement SMF after the SMF has failed to create the PDU session.

[0095] In step 45, a session creation request message is sent to the selected other SMF.

[0096] In some embodiments, when GMF and GPSSF are simultaneously distributed within SMF, the first request message is an SMF discovery request message, and the SMF discovery request message includes information of the VN group to which the UE is joined. Receiving information of the priority SMF transmitted by the NF (i.e., step 42) and acquiring the SMF set includes receiving an SMF discovery response message transmitted by the NF and acquiring information of the priority SMF and the SMF set included in the SMF discovery response message, wherein the SMF set is determined by the NF based on information of the VN group and a second mapping relationship between information of the VN group and information of the SMF. Since information of the VN group and a second mapping relationship between information of the VN group and information of the SMF is recorded in the GMF within the NF, during the process of determining the SMF set, the GMF within the NF can acquire the SMF set by determining information of all SMFs corresponding to the VN group according to the second mapping relationship.

[0097] In some embodiments, GMF and GPSSF are distributed among different NFs, that is, the NF includes a first NF (NF1) and a second NF (NF2), the first NF is NF1 in which GMF is distributed, and the second NF is NF2 in which GPSSF is distributed. The first request message is a VN group priority SMF selection request message, and the SMF discovery method also includes the step of, before transmitting the first request message to the NF (step 41), transmitting an SMF discovery request message containing information of the VN group to the first NF, wherein the SMF discovery request message is configured to indicate the first NF to determine the SMF set; and the step of receiving an SMF discovery response message transmitted by the first NF and obtaining the SMF set included in the SMF discovery response message.

[0098] In some embodiments, transmitting a first request message to the NF (i.e., step 41) includes transmitting a VN group priority SMF selection request message containing an SMF set to the second NF, wherein the VN group priority SMF selection request message is configured to indicate the second NF to determine the priority SMF of the VN group.

[0099] In other words, in an environment where GMF and GPSSF are each distributed in different NFs, AMF first sends an SMF discovery request message containing information about VN groups to the first NF (NF1) where GMF is distributed, and the first NF (NF1) determines a set of SMFs corresponding to the information about VN groups through a second mapping relationship between the information about VN groups and the information about SMFs, and returns an SMF discovery response message containing the set of SMFs to AMF. AMF sends a VN group priority SMF selection request message containing the set of SMFs to the second NF (NF2) where GPSSF is distributed, and the second NF (NF2) obtains the set of SMFs from the VN group priority SMF selection request message and determines the priority SMF of the VN group.

[0100] In some embodiments, the request message for selecting a priority SMF for a VN group also includes information about the VN group, and the second NF (NF2) determines whether it has determined a priority SMF for a corresponding VN group based on the information about the VN group.

[0101] To further clarify the method of the embodiment of this disclosure, the process of SMF discovery in an environment where GMF and GPSSF are each deployed in different NFs will be described in detail with reference to the following example. In this example, NF1 is an NF in which GMF is deployed alone, and NF2 is an NF in which GPSSF is deployed alone, and the set of SMFs corresponding to the 5G VN group to which the UE is joined includes SMF1 and SMF2. As illustrated in FIG. 7, the SMF discovery flow includes steps S1 through S9.

[0102] In step S1, the UE is registered as a 5G core network, that is, the UE is registered as an AMF.

[0103] In step S2, the UE sends a PDU session creation request message to the AMF to trigger the creation of a PDU session under the 5G VN group.

[0104] In step S3, the AMF sends an SMF discovery request message containing information about the 5G VN group to NF1 (i.e., the NF to which the GMF is deployed alone) to initiate a flow for selecting an SMF for the PDU session of the 5G VN group.

[0105] In step S4, NF1 (i.e., NF in which GMF is distributed alone) queries the second mapping relationship between the information of the VN group and the information of the SMF, obtains the set of SMFs (SMF1, SMF2) corresponding to the 5G VN group, and returns an SMF discovery response message containing the set of SMFs as an AMF.

[0106] In step S5, the AMF transmits a VN group priority SMF selection request message to NF2 (i.e., an NF in which the GPSSF is deployed alone), wherein the VN group priority SMF selection request message includes information on the 5G VN group and a set of SMFs.

[0107] In step S6, NF2 (i.e., NF in which GPSSF is deployed alone) determines whether to select a priority SMF for the 5G VN group for the first time according to a first mapping relationship between the information of the VN group and the information of the priority SMF; if NF2 selects a priority SMF for the 5G VN group for the first time, it selects SMF1 from the set of SMFs through a static setting or dynamic selection method and uses it as the priority SMF for the 5G VN group, and locally creates a first mapping relationship between the information of the 5G VN group and the information of SMF1; if NF2 has already selected a priority SMF for the 5G VN group in advance, it obtains the information of the priority SMF (i.e., SMF1) previously selected for the 5G VN group; and NF2 transmits a VN group priority SMF selection response message containing the information of the priority SMF (i.e., SMF1) to the AMF.

[0108] In step S7, the AMF sends a PDU session creation request message to the SMF first (i.e., the priority SMF of the 5G VN group).

[0109] In step S8, SMF1 returns a PDU session creation response message to AMF.

[0110] In step S9, if SMF1 returns a PDU session creation request failure message, AMF determines whether to continue selecting other SMFs in the 5G VN group according to local policy to continue initiating a PDU session creation flow; if to continue selecting other SMFs in the 5G VN group to continue initiating a PDU session creation flow, it selects and accesses other SMFs from the set of SMFs and sends a PDU session creation request message to said other SMFs; if not to continue selecting other SMFs in the 5G VN group to continue initiating a PDU session creation flow, the PDU session is rejected.

[0111] With reference to the following example, the process of SMF discovery in an environment where GMF and GPSSF are deployed in the same NF will be described in detail. In this example, the NF is an NF in which GMF and GPSSF are deployed, and the set of SMFs corresponding to the 5G VN group to which the UE is joined includes SMF1 and SMF2. As illustrated in FIG. 8, the SMF discovery flow includes steps S81 to S89.

[0112] In step S81, the UE is registered as a 5G core network, that is, the UE is registered as an AMF.

[0113] In step S82, the UE sends a PDU session creation request message to the AMF to trigger the creation of a PDU session under the 5G VN group.

[0114] In step S83, the AMF sends an SMF discovery request message containing information about the 5G VN group to the NF (i.e., the NF where the GMF and GPSSF are deployed) to initiate a flow to select an SMF for the PDU session of the 5G VN group.

[0115] In step S84, the NF (i.e., the NF in which the GMF and GPSSF are distributed) queries the second mapping relationship between the information of the VN group and the information of the SMF to obtain the set of SMFs (SMF1, SMF2) corresponding to the 5G VN group.

[0116] In step S85, the NF (i.e., the GPSSF and the NF in which the GPSSF is distributed alone) determines whether to select a priority SMF for the 5G VN group for the first time according to a first mapping relationship between the information of the VN group and the information of the priority SMF, and if the NF selects a priority SMF for the 5G VN group for the first time, it selects SMF1 from the set of SMFs through a static setting or dynamic selection method and uses it as the priority SMF for the 5G VN group, and locally creates a first mapping relationship between the information of the 5G VN group and the information of SMF1; if the NF has already selected a priority SMF for the 5G VN group in advance, it obtains the information of the priority SMF (SMF1) previously selected for the 5G VN group.

[0117] In step S86, the AMF transmits an SMF discovery response message containing information about the SMF set and SMF1 to the NF (i.e., the NF in which the GMF and GPSSF are distributed).

[0118] In step S87, the AMF sends a PDU session creation request message to SMF1 (i.e., the primary SMF).

[0119] In step S88, SMF1 returns a PDU session creation response message to AMF.

[0120] In step S89, if SMF1 returns a PDU session creation request failure message, AMF determines whether to continue selecting other SMFs in the 5G VN group according to local policy to continue initiating a PDU session creation flow; if to continue selecting other SMFs in the 5G VN group to continue initiating a PDU session creation flow, it selects and accesses other SMFs from the set of SMFs and sends a PDU session creation request message to said other SMFs; if not to continue selecting other SMFs in the 5G VN group to continue initiating a PDU session creation flow, the PDU session is rejected.

[0121] With reference to the following examples, the process of registering an SMF as an NF to which a GMV is distributed will be explained in detail. FIG. 9 is a signaling flowchart for registering an SMF as an NF (NF1) to which a GMF is distributed. As shown in FIG. 9, registering an SMF as NF1 includes steps S10 to S30.

[0122] In step S10, SMF transmits a registration request message to NF1, wherein the registration request message includes information about the 5G VN group.

[0123] In step S20, NF1 creates a second mapping relationship between the information of the 5G VN group and the information of the SMF.

[0124] In step S30, NF1 returns a registration response message to SMF.

[0125] The SMF discovery method provided in the embodiment of the present disclosure introduces a GMF logic entity responsible for managing 5G VN group information; said logic entity may be used independently as an NF or as a component of a conventional NF; said logic entity may also introduce a GPSSF logic entity responsible for selecting a priority SMF from a set of SMFs to which the 5G VN group belongs, said logic entity may be used independently as an NF or as a component of a conventional NF, or may be merged into the same NF together with the GMF.

[0126] Based on the same technical concept, an embodiment of the present disclosure is also intended to provide a network function node and includes a first processing module (101), an SMF discovery module (102), and a transmission module (103), as illustrated in FIG. 10.

[0127] The first processing module (101) determines a set of session management function entities (SMF) in response to the reception of a first request message transmitted by an access and mobility management function entity (AMF), wherein the SMFs among the set of SMFs are configured to be SMFs to which the virtual communication network (VN) group to which the user device requesting session creation by accessing the AMFs belongs.

[0128] The SMF discovery module (102) is configured to determine the priority SMF of the VN group, wherein the priority SMF is one of the SMF sets.

[0129] The transmission module (103) is configured to transmit the information of the priority SMF to the AMF.

[0130] In some embodiments, the first processing module (101) is also configured to obtain information about the VN group included in the first request message after receiving the first request message transmitted by the AMF, and before determining the priority SMF of the VN group.

[0131] In some embodiments, the SMF discovery module (102) is configured to use the determined SMF as the priority SMF of the VN group in response to the case where the priority SMF corresponding to the information of the VN group is determined according to a first mapping relationship between the information of the VN group and the information of the priority SMF.

[0132] In some embodiments, the SMF discovery module (102) is also configured to select one SMF from the set of SMFs and use it as the priority SMF of the VN group in response to the case where the priority SMF corresponding to the information of the VN group is not determined according to the first mapping relationship between the information of the VN group and the information of the priority SMF.

[0133] In some embodiments, the SMF discovery module (102) is configured to set a pre-specified SMF among the set of SMFs as the priority SMF of the VN group, or to randomly select one SMF from the set of SMFs to use as the priority SMF of the VN group.

[0134] In some embodiments, as illustrated in FIG. 11, the network function node also further includes a second processing module (104), and the second processing module (104) is configured to create a first mapping relationship between the information of the VN group and the information of the priority SMF after the SMF discovery module (102) selects one SMF from the set of SMFs and uses it as the priority SMF of the VN group.

[0135] In some embodiments, the first request message is an SMF discovery request message, and the first processing module (101) is also configured to acquire information of a VN group included in the SMF discovery request message; and to determine the set of SMFs of the VN group according to the second matching relationship between the information of the VN group and the information of the SMF.

[0136] In some embodiments, the transmitting module (103) transmits an SMF discovery response message to the AMF, wherein the SMF discovery response message is configured to include information of the priority SMF.

[0137] In some embodiments, the first request message is a VN group priority SMF selection request message, and the first processing module (101) acquires a set of SMFs included in the VN group priority SMF selection request message, wherein the set of SMFs is determined by the group management function entity GMF according to the second mapping relationship between the information of the VN group and the information of the SMF and the information of the VN group included in the SMF discovery request message transmitted by the AMF, and the acquired set of SMFs is configured to be transmitted to the AMF.

[0138] In some embodiments, the transmission module (103) is configured to transmit a VN group priority SMF selection response message containing information of the priority SMF to the AMF.

[0139] In some embodiments, as illustrated in FIG. 12, the network function node also further includes a registration module (105), and the registration module (105) is configured to acquire information of a VN group included in the SMF registration request message in response to the reception of an SMF registration request message transmitted by the SMF; and to create a second mapping relationship between the information of the VN group and the information of the SMF.

[0140] An embodiment of the present disclosure is also intended to provide a network function node and includes a receiving module (201), an acquisition module (202), a processing module (203), and a transmitting module (204), as shown in FIG. 13.

[0141] The receiving module (201) is configured to receive a Session Management Function Entity (SMF) discovery request message transmitted by an Access and Mobility Management Function Entity (AMF).

[0142] The acquisition module (202) is configured to acquire information about the virtual communication network VN group included in the SMF discovery request message.

[0143] The processing module (203) is configured to determine the set of SMFs of the VN group according to the information of the VN group and the second matching relationship between the information of the VN group and the information of the SMF.

[0144] The transmission module (204) is configured to transmit an SMF discovery response message containing the set of SMFs to the AMF, so that the AMF initiates a priority SMF selection request.

[0145] In some embodiments, as illustrated in FIG. 14, the network function node also further includes a registration module (205), and the registration module (205) is configured to acquire information of a VN group included in the SMF registration request message in response to the reception of an SMF registration request message transmitted by the SMF; and to create a second mapping relationship between the information of the VN group and the information of the SMF.

[0146] An embodiment of the present disclosure is also configured to provide an access and mobility management function entity, comprising, as illustrated in FIG. 15, an SMF discovery module (301), wherein the SMF discovery module (301) transmits a first request message to a network function node (NF) in response to receiving a session creation request message transmitted by a user device (UE), wherein the first request message is configured to indicate the NF to determine the priority SMF of the virtual communication network (VN) group to which the UE belongs, and wherein the priority SMF is one of the SMFs in the set of SMFs, and the SMF in the set of SMFs is the SMF to which the VN group belongs; and wherein the NF receives information of the priority SMF transmitted by the NF and transmits a session creation request message to the priority SMF corresponding to the information of the priority SMF.

[0147] In some embodiments, as illustrated in FIG. 16, the access and mobility management function entity also further includes an acquisition module (302), and the acquisition module (302) is configured to acquire a set of SMFs before sending a session creation request message to a priority SMF corresponding to the information of the priority SMF.

[0148] The access and mobility management function entity also further includes an SMF rediscovery module (303), and the SMF rediscovery module (303) is configured to select other SMFs other than the priority SMF from the set of SMFs and send a session creation request message to the selected other SMFs in response to the reception of a session creation request failure message sent by the priority SMF after the SMF discovery module (301) has sent a session creation request message to the priority SMF corresponding to the information of the priority SMF.

[0149] In some embodiments, the first request message is an SMF discovery request message, and the SMF discovery request message includes information of the VN group to which the UE is joined, and the acquisition module (302) acquires information of the priority SMF and the SMF set included in the SMF discovery response message transmitted by the NF, wherein the SMF set is configured such that the NF determines the information of the VN group and the second mapping relationship between the information of the VN group and the information of the SMF.

[0150] In some embodiments, the NF includes a first NF and a second NF, and the first request message is a VN group priority SMF selection request message, and the acquisition module (302) also transmits an SMF discovery request message containing information of the VN group to the first NF, wherein the SMF discovery request message is configured to determine the SMF set by indicating the first NF; and, the acquisition module is configured to receive an SMF discovery response message transmitted by the first NF and to acquire the SMF set included in the SMF discovery response message.

[0151] The SMF discovery module (301) transmits VN group priority SMF selection request information containing the set of SMFs to the second NF, wherein the VN group priority SMF selection request message is configured to indicate the second NF to determine the priority SMF of the VN group.

[0152] In some embodiments, the VN group priority SMF selection request message also includes information about the VN group.

[0153] An embodiment of the present disclosure is also provided for providing an electronic device, said electronic device comprising at least one processor and a storage device; said storage device stores at least one computer program, and when said at least one computer program is executed by said at least one processor, said at least one processor implements the SMF discovery method said above.

[0154] An embodiment of the present disclosure is also intended to provide a computer-readable storage medium, wherein a computer program is stored therein and configured to implement the SMF discovery method as described above when the computer program is executed by a processor.

[0155] Those skilled in the art will understand that all or part of the steps and functional modules / units of the device disclosed in the context may be implemented in software, firmware, hardware, and a suitable combination thereof. In hardware implementations, the distinction between the functional modules / units mentioned in the above description is not necessarily a distinction between physical elements, so that a single physical element may have multiple functions, or a single function or step may be performed by multiple physical elements working together. Some or all physical elements may be implemented through software executed by a processor (e.g., a central processing unit, a digital signal processor, or a microprocessor), or through hardware, or through an integrated circuit such as a dedicated integrated circuit. Such software may be distributed on a computer-readable medium, and the computer-readable medium may include a computer storage medium (or non-volatile medium) and a communication medium (or volatile medium). To those skilled in the art, it is obvious that the term computer storage medium may be volatile and non-volatile, removable and non-removable media implemented in any method or technique for storing information (e.g., computer-readable instructions, data structures, program modules or other data). Computer storage medium includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, DVD or other optical storage media, magnetic cartridge, magnetic tape, magnetic disk storage medium or other magnetic storage device, or any other medium that stores the necessary information and is readable by a computer.Additionally, to those skilled in the art, a communication medium typically includes computer-readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier or other transmission mechanism, and may include any information transmission medium.

[0156] Exemplary embodiments have already been disclosed in the text and specific terms have been used; however, these terms are to be used and interpreted only in a general descriptive sense and are not intended to be limiting. In some embodiments, it will be obvious to those skilled in the art that, unless otherwise explicitly stated, features, properties, and / or elements described with reference to specific embodiments may be used alone or in combination with features, properties, and / or elements described with reference to other embodiments. Accordingly, those skilled in the art will understand that various changes to the form and details may be made without departing from the scope of this disclosure as set forth in the appended claims.

Claims

Claim 1 A method for discovering a session management function entity (SMF) performed by a network function node (NF), wherein, in response to the reception of a first request message transmitted by an access and mobility management function entity (AMF), a set of SMFs comprising a plurality of session management function entities (SMFs) is determined, wherein a virtual communication network (VN) group comprising a plurality of user devices (UEs) that access the AMFs and request session creation belongs to the plurality of SMFs of the set of SMFs; and a priority SMF of the VN group is determined, wherein the priority SMF is one of the SMFs in the set of SMFs; A method for discovering a session management function entity (SMF), comprising: transmitting information of the priority SMF to the AMF; wherein the AMF accesses the priority SMF in response to a session creation request message transmitted by any UE within the VN group and transmits a session creation request message to the priority SMF; and, when the AMF receives a session creation request failure message transmitted by the priority SMF, selects another SMF from the set of SMFs excluding the priority SMF and transmits the session creation request message to the other SMF. Claim 2 A method according to claim 1, further comprising: obtaining information of a VN group included in the first request message after receiving a first request message transmitted by the AMF, and before determining the priority SMF of the VN group; and determining the priority SMF of the VN group, in response to the case where the priority SMF corresponding to the information of the VN group is determined according to a first mapping relationship between the information of the VN group and the information of the priority SMF, using the determined SMF as the priority SMF of the VN group. Claim 3 A method further comprising, in paragraph 2, determining the priority SMF of the VN group, selecting one SMF from the set of SMFs and using it as the priority SMF of the VN group as a response to the case where the priority SMF corresponding to the information of the VN group was not determined according to the first mapping relationship between the information of the VN group and the information of the priority SMF. Claim 4 A method according to claim 3, wherein selecting one SMF from the set of SMFs and using it as the priority SMF of the VN group comprises making a pre-specified SMF from the set of SMFs the priority SMF of the VN group, or randomly selecting one SMF from the set of SMFs and using it as the priority SMF of the VN group. Claim 5 A method further comprising, in paragraph 3, selecting one SMF from the set of SMFs and using it as the priority SMF of the VN group, and then generating a first mapping relationship between the information of the VN group and the information of the priority SMF. Claim 6 The method according to claim 1, wherein the first request message is an SMF discovery request message, and the SMF discovery method further comprises: obtaining information of a VN group included in the SMF discovery request message after receiving the first request message transmitted by the AMF; and determining the SMF set comprises determining the SMF set of the VN group according to a second matching relationship between the information of the VN group and the information of the SMF. Claim 7 A method according to claim 6, wherein transmitting information of the priority SMF to the SMF comprises transmitting an SMF discovery response message to the AMF, wherein the SMF discovery response message includes information of the priority SMF. Claim 8 A method comprising: in claim 1, wherein the first request message is a VN group priority SMF selection request message, and determining the SMF set is to acquire the SMF set included in the VN group priority SMF selection request message, wherein the SMF set is determined by a group management function entity (GMF) according to a second mapping relationship between the information of the VN group and the information of the SMF and the information of the VN group included in the SMF discovery request message transmitted by the AMF, and transmitting the acquired SMF set to the AMF. Claim 9 A method according to claim 8, wherein transmitting the information of the priority SMF to the SMF comprises transmitting a VN group priority SMF selection response message containing the information of the priority SMF to the AMF. Claim 10 A method according to claim 1, further comprising: acquiring information of a VN group included in the SMF registration request message as a response to the reception of an SMF registration request message transmitted by the SMF; and generating a second mapping relationship between the information of the VN group and the information of the SMF. Claim 11 A method for discovering a Session Management Function Entity (SMF) performed by a Network Function Node (NF), comprising: in response to the reception of a Session Management Function Entity (SMF) discovery request message transmitted by an Access and Mobility Management Function Entity (AMF), acquiring information of a Virtual Network (VN) group included in the SMF discovery request message; determining a set of SMFs of the VN group according to a second matching relationship between the information of the VN group and the information of the VN group and the information of the SMF, wherein the set of SMFs includes a plurality of SMFs and the VN group, which includes a plurality of User Devices (UEs) requesting session creation by accessing the AMF, belongs to the plurality of SMFs of the set of SMFs; transmitting an SMF discovery response message containing the set of SMFs to the AMF so that the AMF initiates a priority SMF selection request; and in response to the reception of a VN group priority SMF selection request message transmitted by the AMF, determining a priority SMF of the VN group from the set of SMFs. A method for discovering an SMF applied to a session creation process, comprising: transmitting information of the priority SMF to the AMF; wherein the AMF accesses the priority SMF in response to a session creation request message transmitted by any UE within the VN group and transmits a session creation request message to the priority SMF; and, when the AMF receives a session creation request failure message transmitted by the priority SMF, selects another SMF from the set of SMFs excluding the priority SMF and transmits the session creation request message to the other SMF. Claim 12 A method according to claim 11, further comprising: acquiring information of a VN group included in the SMF registration request message as a response to the reception of an SMF registration request message transmitted by the SMF; and generating a second mapping relationship between the information of the VN group and the information of the SMF. Claim 13 A method for discovering a Session Management Function Entity (SMF) performed by an Access and Mobility Management Function Entity (AMF), wherein, in response to the reception of a session creation request message transmitted by a UE belonging to a virtual network (VN) group comprising a plurality of user devices (UEs), a first request message is transmitted to a network function node (NF), wherein the first request message is configured to instruct the NF to determine the priority Session Management Function Entity (SMF) of the virtual network (VN) group to which the UE belongs from a set of SMFs comprising a plurality of SMFs, and wherein the VN group comprising the plurality of UEs belongs to the plurality of SMFs; receive information of the priority SMF transmitted by the NF; and, in response to a session creation request message transmitted by any UE within the VN group, transmit a session creation request message to the priority SMF corresponding to the information of the priority SMF; A method for discovering an SMF, comprising, when receiving a session creation request failure message transmitted by the priority SMF, selecting another SMF from the set of SMFs excluding the priority SMF and transmitting the session creation request message to the selected other SMF. Claim 14 A method further comprising, in paragraph 13, obtaining the set of SMFs before transmitting a session creation request message to the priority SMF corresponding to the information of the priority SMF. Claim 15 A method comprising: in paragraph 14, wherein the first request message is an SMF discovery request message, and the SMF discovery request message includes information of a VN group to which the UE belongs, and acquiring information of a priority SMF transmitted by the NF and the set of SMFs comprises receiving an SMF discovery response message transmitted by the NF and acquiring information of a priority SMF and the set of SMFs included in the SMF discovery response message, wherein the set of SMFs is determined by the NF through information of the VN group and a second mapping relationship between information of the VN group and information of SMFs. Claim 16 In claim 13, the above NF includes a first NF and a second NF, the above first request message is a VN group priority SMF selection request message, and the above SMF discovery method further comprises: transmitting an SMF discovery request message containing VN group information to the first NF before transmitting the first request message to the above NF, wherein the SMF discovery request message indicates the first NF to determine the SMF set; and receiving an SMF discovery response message transmitted by the first NF and obtaining the SMF set included in the SMF discovery response message; and transmitting the first request message to the above NF is configured to transmit VN group priority SMF selection request information containing the SMF set to the second NF, wherein the VN group priority SMF selection request message indicates the second NF to determine the priority SMF of the VN group. Claim 17 In paragraph 16, the method of including information of the VN group in the VN group priority SMF selection request message. Claim 18 An electronic device comprising: at least one processor; and a storage device storing at least one computer program, wherein, when the at least one computer program is executed by the at least one processor, the at least one processor is configured to implement an SMF discovery method according to any one of claims 1 to 17. Claim 19 A computer-readable storage medium in which a computer program is stored and, when said computer program is executed by a processor, a method for discovering an SMF according to any one of claims 1 to 17 is performed. Claim 20 delete Claim 21 delete Claim 22 delete

Images