CN113891430A

CN113891430A - Communication method, device and system

Info

Publication number: CN113891430A
Application number: CN202111198151.9A
Authority: CN
Inventors: 马景旺; 周彧; 张智; 帅扬来
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-11-28
Filing date: 2017-11-28
Publication date: 2022-01-04
Also published as: CN109842906B; CN109842906A

Abstract

The application relates to the technical field of wireless communication, and provides a communication method, which comprises the following steps: the first network function storage function network element receives first information from the first network function network element, wherein the first information comprises the NF type of a target network function network element, and the target network function network element is a network function network element requested to be discovered by the first network function network element. The first network function storage function network element sends first information to the second network function storage function network element, receives second information from the second network function storage function network element, and sends the second information to the first network function network element. Wherein the second information comprises an identifier of the target network function network element. By the scheme provided by this embodiment, the network functional network element of the core network can discover the target network functional network element of the access network, and establish communication connection with the target network functional network element. The service access mode distributes the signaling in the interaction among network elements for processing, thereby improving the service efficiency.

Description

Communication method, device and system

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method, an apparatus, and a system for communication.

Background

An Evolved Packet Core (EPC) adopts an architecture mode of a Network Element (NE). For example, the architecture encompasses NEs that include: mobility Management Entity (MME), Serving Gateway (S-GW), Packet Data Network Gateway (P-GW), and so on. Based on this architecture, Network Functions (NFs) provided by the EPC to the users (e.g., mobility management, bearer management, location management, etc.) are implemented by service features and processing logic solidified in the NEs and flow messages between the NEs.

However, in the fifth generation (5G) communication network, with the continuous expansion of business model and the continuous development of technology, the user service will put more demands (for example, the demand of ultra-low latency communication and the demand of high reliability communication, etc.), so the core network needs to support more new NFs. To meet this requirement, NEs (e.g., MMEs or S-GWs) in the EPC are split into different NF network elements according to the category of function. For example, various functions such as an authentication and security function, a session management function, a mobility management function, and an access control function are separated. Each NF network element interacts with other NF network elements through a defined service interface and provides services.

Furthermore, the functions in the 5G access network are also decoupled into Central Unit-Control plane (CU-C), Central Unit-User plane (CU-U) and Distributed Unit (DU) functions.

When the current core network and the access network perform service access mutually, the access network needs to perform signaling interaction with the NE of the core network through the MME network element. That is, after the communication connection between the core network and the access network is established from the beginning, all signaling for interaction is processed through the MME network element. This increases the load of the MME network element for processing the signaling, and the more services accessed, the larger the load of the network element, the longer the delay for processing the signaling, thereby causing a reduction in service efficiency.

Disclosure of Invention

The embodiment of the invention provides a communication method, a communication device and a communication system.

In one aspect, an embodiment of the present application provides a method of communication, where the method includes: a first network function storage function network element (e.g., a first NRF network element) receives first information from a first network function network element (e.g., a first NF network element), wherein the first information includes an NF type of a target network function network element (e.g., the NF type is represented by a name of the network function network element), the target network function network element requesting a discovered network function network element for the first network function network element; the first network function storage function network element sends first information to a second network function storage function network element (e.g., a second NRF network element); the first network function storage function network element receives second information from a second network function storage function network element, wherein the second information comprises an identifier of a target network function network element; and the first network function storage function network element sends the second information to the first network function network element.

According to the method, the network function network element of the core network can find the target NF network element of the access network with the specific NF type, and the network function network element of the access network can also find the target network function network element of the core network with the specific NF type. Then, the network functional network element of the core network can directly establish communication connection with the network functional network element of the access network and access services with each other. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

In one possible design, before the first network function storage function network element sends the first information to the second network function storage function network element, the first network function storage function network element determines that the first network function network element allows to discover the target network function network element according to third information, where the third information is used to indicate an NF type of the network function network element that the first network function network element allows to discover, and for example, the third information may also be called discovery policy information. Therefore, the NF type of the network functional network element allowed to be discovered by the first network functional network element is configured, so that the access authority of the network functional network elements of the core network and the access network can be limited, and the communication safety between the core network and the access network is improved.

In one possible design, the first network function storage function network element is a network function storage function network element of a core network, the second network function storage function network element is a network function storage function network element of an access network, and the first network function storage function network element determines the second network function storage function network element before the first network function storage function network element sends the first information to the second network function storage function network element. Therefore, the network function storage function network element of the core network can determine the network function storage function network element of the access network corresponding to the network function storage function network element of the core network.

In one possible design, before the network function storage function network element of the core network determines the network function storage function network element of the access network, the network function storage function network element of the core network receives an Area identifier of the network function storage function network element of the access network from the network management system or the network function storage function network element of the access network, where the Area identifier is used to indicate an Area served by the network function storage function network element of the access network, and for example, the Area identifier may be a Tracking Area Identifier (TAI). Therefore, when the network function storage function network element of the core network corresponds to the network function storage function network elements of the plurality of access networks, the core network can find the network function storage function network elements of one or more access networks which can provide services in the specified area according to the area identification of the network function storage function network element of the access network.

In one possible design, the first information further includes identification information, where the identification information includes an area identifier, a service identifier, or a network slice identifier of the target network function network element. The area identifier is used for indicating an area served by the target network function network element, the service identifier is used for indicating a service provided by the target network function network element, and the network slice identifier is used for indicating a network slice type supported by the target network function network element. Therefore, the network function network element of the access network or the network function network element of the core network may request a target network function network element belonging to a specific NF type in a specified area, or may request a target network function network element belonging to a specific NF type and capable of providing a plurality of specific services, or may request a target network function network element belonging to a specific NF type and capable of supporting a specific network slice type.

In one possible design, the second information further includes an association between the identification information and an identification of the target network function network element. Therefore, the network function network element of the access network or the network function network element of the core network may receive the area identifier of the target network function network element, or may receive the service identifier that the target network function network element can provide, or may receive the specific network slice type that the target network function network element can support.

In another aspect, the present application further discloses a communication method, including: a network function network element of the access network (e.g., an NF network element of the access network) sends first information to a network function storage function network element of the access network (e.g., an NRF network element of the access network), wherein the first information includes an NF type of a target network function network element of the core network (e.g., a target NF network element of the core network); and the network function network element of the access network receives second information from the network function storage function network element of the access network, wherein the second information comprises the identification of the target network function network element. The target network function network element of the core network is a network function network element of the core network requested to be discovered by the network function network element of the access network.

According to the method, the network function network element of the access network can receive the target network function network element of the core network of the specific NF type from the network function storage function network element of the access network. Then, the network functional network element of the access network can directly establish communication connection with the target network functional network element of the core network and access services with each other. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

In another aspect, the present application further discloses a communication method, including: receiving, by a second network function storage function network element (e.g., a second NRF network element), first information from a first network function storage function network element (e.g., a first NRF network element), the first information comprising an NF type of a target network function network element (e.g., a target NF network element); and the second network function storage function network element sends second information to the first network function storage function network element, wherein the second information comprises the identification of the target network function network element.

According to the method, the network function storage function network element of the core network may receive the identifier of the target network function network element of the access network of the specific NF type from the network function storage function network element of the access network, and the network function storage function network element of the access network may receive the identifier of the target network function network element of the core network of the specific NF type from the network function storage function network element of the core network. Then, the network functional network element of the core network can directly establish communication connection with the target network functional network element of the access network and access services mutually through the identifier of the target network functional network element of the access network, and the network functional network element of the access network can also directly establish communication connection with the target network functional network element of the core network and access services mutually through the identifier of the target network functional network element of the core network. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

In one possible design, the first information further includes an NF type of a first network function network element (e.g., a first NF network element), and the target network function network element requests the discovered network function network element for the first network function network element. Before the second network function storage function network element sends the second information to the first network function storage function network element, the method further comprises: the second network function storage function network element determines that the target network function network element is allowed to be discovered by the first network function network element according to fourth information and the first information, wherein the fourth information is used for indicating the NF type allowing the target network function network element to be discovered, and for example, the fourth information may also be called discovery policy information. Therefore, by configuring the network function network element of each access network to be discovered by the network function network elements of which types of core networks and the network function network element of each core network to be discovered by the network function network elements of which types of access networks, the mutual access authority of the network function network elements of the core networks and the network function network elements of the access networks can be further limited, and the communication safety between the core networks and the access networks is further improved.

In one possible design, the second network function storage function network element is a network function storage function network element of an access network, the first network function storage function network element is a network function storage function network element of a core network, and before the second network function storage function network element sends the second information to the first network function storage function network element, the second network function storage function network element determines the target network function network element according to the first information and NF description information of the network function network element of the access network, wherein the NF description information includes an NF type of the network function network element of the access network. Therefore, the network function storage function network element of the access network can determine the target network function network element of the access network.

In one possible design, the network function storage function network element of the access network may determine the target network function network element according to the first information and the NF description information of the network function network element of the access network by: the first information further comprises an area identifier of a target network function network element, the NF description information further comprises an area identifier of a network function network element of the access network, and the network function storage function network element of the access network determines the target network function network element according to the NF type and the area identifier of the target network function network element in the first information and the NF type and the area identifier of the network function network element of the access network in the NF description information;

or the first information further comprises a service identifier of the target network function network element, the NF description information further comprises a service identifier of the network function network element of the access network, and the network function storage function network element of the access network determines the target network function network element according to the NF type and the service identifier of the target network function network element in the first information and the NF type and the service identifier of the network function network element of the access network in the NF description information;

or the first information further includes a network slice identifier of the target network function network element, the NF description information further includes a network slice identifier of the network function network element of the access network, and the network function storage function network element of the access network determines the target network function network element according to the NF type and the network slice identifier of the target network function network element in the first information and the NF type and the network slice identifier of the network function network element of the access network in the NF description information.

Therefore, the network function storage function network element of the access network can determine the target network function network element of the access network belonging to the specific NF type in the designated area, or the network function storage function network element of the access network can also determine the target network function network element of the access network belonging to the specific NF type and capable of providing multiple specific services, or the network function storage function network element of the access network can also determine the target network function network element of the access network belonging to the specific NF type and capable of supporting the specific network slice type.

In one possible design, a network function storage function network element of the access network receives NF description information from a target network function network element; alternatively, the second Network Function storage Function Network element receives NF description information from a Network Management system (e.g., an Operation Administration and Maintenance (OAM) system or a Network Slice Subnet Management Function (NSSMF) system). Therefore, the network function storage function network element of the access network can obtain the NF description information of the target network function network element, and further determine the target network function network element capable of providing the specific service.

In one possible design, the network function storage function network element of the access network receives request information from the network management system or the target network function network element, the request information being used to request the network function storage function network element of the access network to register the target network function network element; and the network function storage function network element of the access network sets the state information of the target network function network element to be in an unavailable state. Therefore, the target network function network element can make the network function storage function network element of the access network know that the target network function network element is temporarily unavailable by requesting to register the network function storage function network element of the access network.

In another aspect, the present application further discloses a communication method, including: a network function network element of the access network (e.g., an NF network element of the access network) sends NF description information of the network function network element of the access network to a network function storage function network element of the access network (e.g., an NRF network element of the access network), wherein the NF description information includes an NF type of the network function network element of the access network; and the network function network element of the access network receives a first response message from the network function storage function network element of the access network, wherein the first response message is used for indicating that the network function network element of the access network is registered completely.

According to the method, the network function storage function network element of the access network can obtain NF description information of the network function network element of the access network. After receiving the first information, the network function storage function network element of the access network may find a target network function network element capable of providing a specific service by querying the NF description information.

In one possible design, the network function network element of the access network sends request information to the network function storage function network element of the access network, and the request information is used to request, to the network function storage function network element of the access network: registering a network function network element of an access network; and the network function network element of the access network receives a second response message from the network function storage function network element of the access network, wherein the second response message is used for indicating that the network function network element of the access network completes the registration. Therefore, a certain network function network element which is abnormal and cannot normally work in the access network requests the network function storage function network element of the access network to register, so that the network function storage function network element of the access network can know which network function network element of the access network is temporarily unavailable, and when the network function storage function network element of the access network searches for a target network function network element, the unavailable network function network element does not need to be compared, so that the working load of the network function storage function network element of the access network is reduced, and the service efficiency is improved.

In one possible design, the NF description information further includes at least one of a network address (e.g., an IP address), a service identification, an area identification, or a network slice identification of a network functional network element of the access network. Wherein the network address is used to indicate a location of a network function network element of the access network. The service identifier is used for indicating a service provided by a network function network element of the access network. The area identification is used for indicating an area served by a network function network element of the access network. The network slice identifier is used for indicating the network slice type supported by the network function network element of the access network. Therefore, the network function storage function network element of the access network can determine the target network function network element of the access network belonging to a specific NF type in the designated area, or the target network function network element of the access network belonging to the specific NF type and capable of providing a plurality of specific services, or the target network function network element of the access network belonging to the specific NF type and capable of supporting the specific network slice type according to the first information and the NF description information of the network function network element of the access network.

In still another aspect, the present embodiment provides a communication apparatus having a function of implementing the behavior of the first network function storage function network element (e.g., the first NRF network element) in the foregoing method. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions. In one possible design, the communication device includes a processor and a transceiver, and the processor is configured to process the communication device to perform the corresponding functions of the method. The transceiver is used for realizing the communication between the communication device and the first network function network element/the second network function storage function network element. The communication device may also include a memory, coupled to the processor, that retains program instructions and data necessary for the communication device.

In another aspect, an embodiment of the present application provides a communication apparatus having a function of implementing a behavior of a network function network element of an access network (e.g., an NF network element of the access network) in the foregoing method. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions. In one possible design, the communication device includes a processor and a transceiver in its structure, and the processor is configured to perform the corresponding functions of the above method. The transceiver is used for realizing the communication between the communication device and the network function storage function network element of the access network. The communication device may also include a memory, coupled to the processor, that retains program instructions and data necessary for the communication device.

In still another aspect, the present application provides a communication apparatus having a function of implementing the behavior of the second network function storage function network element (e.g., the second NRF network element) in the foregoing method. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions. In one possible design, the communication device includes a processor and a transceiver, and the processor is configured to process the communication device to perform the corresponding functions of the method. The transceiver is used for realizing the communication between the communication device and the first network function storage function network element/the target network function network element/the network management system. The communication device may also include a memory, coupled to the processor, that retains program instructions and data necessary for the communication device.

In yet another aspect, the present application provides a computer-readable storage medium having stored therein instructions, which when executed on a computer, cause the computer to perform the method of the above aspects.

In yet another aspect, the present application provides a computer program product containing instructions which, when executed on a computer, cause the computer to perform the method of the above aspects.

In yet another aspect, the present application provides a chip system, which includes a processor for enabling the communication apparatus to implement the functions recited in the above aspects, for example, to generate or process information recited in the above methods. In one possible design, the system-on-chip further includes a memory for storing program instructions and data necessary for data transmission. The chip system may be constituted by a chip, or may include a chip and other discrete devices.

Drawings

In order to more clearly illustrate the technical solution in the embodiment of the present invention, the drawings required to be used in the embodiment of the present invention will be described below.

Fig. 1 is a schematic diagram of a 5G communication system provided in an embodiment of the present application;

fig. 2 is a flowchart of a method for discovering an NF network element of an access network by an NF network element of a core network according to an embodiment of the present application;

fig. 3A and fig. 3B are signaling interaction diagrams of registration of an NF network element of an access network to an NRF network element of the access network according to an embodiment of the present application;

fig. 4A and 4B are signaling interaction diagrams of an NF network element of an access network registering with an NRF network element of the access network according to an embodiment of the present application;

fig. 5 is a flowchart of a method for discovering an NF network element of a core network by an NF network element of an access network according to an embodiment of the present application;

fig. 6 is a flow chart of a method of communication provided in accordance with an embodiment of the present application;

fig. 7A and 7B are schematic structural diagrams of a communication device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application.

In the present application, "a plurality" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

Fig. 1 is a schematic diagram of a 5G communication system according to an embodiment of the present application. In the core network architecture of the 5G mobile network, the control plane function and the forwarding plane function of the mobile gateway are decoupled, and the separated control plane function and the MME are merged into a unified Control Plane (CP). The User Plane Function (UPF) network element can realize the User plane functions (SGW-U and PGW-U) of the SGW and the PGW. Further, the unified control plane network element may be decomposed into an access and mobility management function (AMF) network element and a Session Management Function (SMF) network element.

As shown in fig. 1, an embodiment of the present application provides a communication system, where the communication system includes a Network Function storage Function (NRF) 101 Network element of a core Network, an NRF Network element 112 of an access Network, an NF Network element of the core Network, and an NF Network element of the access Network. For example, the NF Network element of the core Network may be any one of a Network Slice Selection Function (NSSF) Network element 102, a Network open Function (NEF) 103 Network element, a Policy Control Function (PCF) Network element 104, a Unified Data Management (UDM) Network element 105, an Application Function (AF) Network element 106, an Authentication service Function (AUSF) Network element 107, an AMF 108 Network element, a Network Data analysis Function (Network analysis Function NWDAF) 109, and an SMF Network element 110. In the access network architecture of the 5G mobile network, in order to support flexible deployment of different service requirements and functions, the functions in the access network are decoupled into CU-C, CU-U and DU functions. The access network NF network element may be any one of the NWDAF network element 111, the DU network element 113, or the CU network element 114 (or, the CU-C network element 1141 in the CU network element 114, or the CU-U network element 1142 in the CU network element 114).

On the core network side, the network functions that the NRF network element 101 of the core network can provide include: the service discovery function, the function of maintaining the NF description information of the effective NF network element in the core network, and the function of maintaining the service supported by the effective NF network element in the core network. The service discovery function is to receive a discovery request message from an NF network element of any one of the core networks and provide information of a target NF network element requesting discovery to the NF network element.

The network functions that the NSSF network element 102 of the core network can provide include: a Network Slice (Network Slice) is selected for the user equipment.

The network functions that can be provided by the NEF network element 103 of the core network include services and capabilities of externally provided network elements, application functions, and edge computing. Optionally, the NEF network element 103 also provides an application function for securely providing information to the 3GPP network, such as a mobility mode and a communication mode. In this case, the NEF network element 103 may also provide network functions that authenticate, authorize and limit the above-described application functions.

The network functions that the PCF network element 104 of the core network can provide include: a unified policy framework is provided to manage the network. Optionally, PCF network element 104 may provide policies for control plane functions to perform network management. Alternatively, PCF network element 104 may also provide a front end to access subscription information related to decision policies of a Unified Data Repository (UDR).

The network functions that the UDM network element 105 of the core network can provide include: and storing the subscription data of the user. For example, the subscription data of the user includes subscription data related to mobility management and subscription data related to session management.

The network functions that the AF network element 106 of the core network can provide include: and performing policy control and charging control on the transmission plane resources.

The network functions that the AUSF network element 107 of the core network can provide include: authentication control for user equipment.

The network functions that the AMF network element 108 of the core network can provide include: and the system is responsible for registration, mobility management, tracking area update and the like of the terminal equipment.

The network functions that the NWDAF network element 109 of the core network can provide include: managing network analysis logic functions. Optionally, the NWDAF network element 109 may also provide the network data analysis information of the specific slice to the PCF network element according to the network slice dimension.

The network functions that the SMF network element 110 of the core network can provide include: and is responsible for session management of the terminal equipment. For example, session management includes selection of a user plane device, reselection of the user plane device, network protocol (IP) address allocation, quality of service (QoS) control, and establishment, modification, or release of a session.

On the access network side, the NRF network element 112 of the access network is a new network element proposed according to an embodiment of the present application, and can provide network functions including: and the service discovery function is to receive the request message from the NF network element of the access network and provide the NF network element with the information of the target NF network element of the discovered access network. The NRF network element 112 of the access network may also provide network functions including: and maintaining NF description information of the effective NF network elements in the access network, and maintaining services supported by the effective NF network elements in the access network.

The network functions provided by the NWDAF network element 111 of the access network include: managing network analysis logic functions. Optionally, the NWDAF network element 111 may also provide network data analysis information to the NWDAF network element 109 of the core network or a network element of the access network (e.g., the CU-C network element 1141).

The DU network element 113 of the Access network implements functions of Radio Link Control (RLC), Media Access Control (MAC), and physical layer (PHY) protocol.

The network functions provided by the CU network element 114 of the access network include: radio Resource Control (RRC), Service Data Adaptation (SDAP), and Packet Data Convergence (PDCP) protocols. Optionally, the network functions provided by the CU network element 114 also include control functions for DUs. Optionally, the network functions provided by the CU network element 114 further include supporting interface functions with the core network. The CU network element 114 may also be decoupled into a CU-C network element 1141 and a CU-U network element 1142.

The network functions that the CU-C network element 1141 of the access network can provide include: control plane functions of PDCP and RRC protocols are supported. Optionally, the network functions provided by the CU-C network element 1141 also include control of the DU network element 113 and the CU-U network element 1142.

The network functions that the CU-U network element 1142 of the access network can provide include: user plane functions of PDCP and SDAP are supported.

Each NF network element above may be a network element implemented on dedicated hardware, or may be a software instance running on dedicated hardware, or may be an instance of a virtualization function on a suitable platform, for example, the virtualization platform may be a cloud platform.

It should be noted that the NF network element of the core network and the NF network element of the access network are not limited to the above listed network elements, and may also be a network element that needs service interaction in the core network and the access network in a future communication system.

The embodiment of the application is also suitable for the network architecture supporting the network slice. Based on virtualization and the like, a common network infrastructure of the core network is sliced into N network slices. Network slices are used to implement network services that are needed for a certain service or services. The types of network slices may include: enhanced Mobile Broadband (eMBB), Ultra-reliable and low latency communications (URLLC), mass Internet of Things (mass Internet of Things, mrlot), and so on. The type of Slice may be identified by Single Network Slice Selection Assistance information (S-NSSAI). It is also possible to select the same network slice instance by different S-NSSAIs.

In addition, the embodiment of the application can also be applied to other communication technologies facing the future. The system architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not form a limitation on the technical solution provided in the embodiment of the present application, and as a person of ordinary skill in the art knows that along with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

The following takes the 5G communication system shown in fig. 1 as an example, and the technical solution of the present application is described in detail through some embodiments. The following several embodiments may be combined with each other and may not be described in detail in some embodiments for the same or similar concepts or processes.

Fig. 2 is a flowchart of a method for discovering an NF network element of an access network by an NF network element of a core network according to an embodiment of the present application. The method can be used for the NF network element of the core network to find the NF network element of the access network with a specific NF type according to the service requirement so as to obtain the scene of the corresponding network function. The access network NF network element to be discovered by the core network NF network element may also be called a target NF network element of the access network. For example, the NF network element of the core network may be any one of NSSF102, NEF 103, PCF 104, UDM 105, AF 106, AUSF 107, AMF 108, NWDAF109, or SMF 110 in fig. 1. The target NF network element of the access network may be any one of the NWDAF 111, DU 113, or CU 114 in fig. 1 (or CU-C1141 in CU 114 or CU-U1142 in CU 114). For example, when the NEF 103 of the core network needs to obtain the service of counting the number of terminal devices in a certain area from the CU-C1141 of the access network, the NEF 103 of the core network may first discover the CU-C1141 of the access network by the following mechanism, and then obtain the service by accessing the CU-C1141 of the access network. The CU-C1141 of the access network has network functions required for realizing the services.

As shown in fig. 2, the method may include:

s201: and the NF network element of the core network sends the first information to the NRF network element of the core network. Accordingly, the NRF network element of the core network receives the first information from the NF network element of the core network. Wherein the first information comprises an NF type of a target NF network element of the access network.

For example, the NRF network element of the core network may be the NRF network element 101 in fig. 1.

The NF type of the target NF network element of the access network may be represented by a name of the target NF network element of the access network. For example, the NF type of the target NF network element of the access network may be NWDAF, DU, CU-C or CU-U.

S203: the NRF network element of the core network determines the NRF network element of the access network.

The NRF network element of the access network described above may be, for example, NRF network element 112 in fig. 1.

For example, when the NRF network element of the core network corresponds to the NRF network element of the access network, the NRF network element of the core network may determine the NRF network element of the access network corresponding to the NRF network element of the core network.

The above step S203 is an optional step. The NRF network element of the core network may also determine the NRF network element of the access network by other manners, which is not limited herein.

S204: and the NRF network element of the core network sends the first information to the NRF network element of the access network. Accordingly, the NRF network element of the access network receives the above-mentioned first information from the NRF network element of the core network.

S205: the NRF network element of the access network determines a target NF network element of the access network.

For example, the NRF network element of the access network determines the target NF network element of the access network according to the first information and the NF description information of the NF network element of the access network. The NF description information of the NF network element of the access network comprises the NF type of the NF network element of the access network. For example, the NF description information of the NF network element of the access network is shown in table 1: NF description information of a CU-C1 network element of the access network is CU-C; and the NF description information of the CU-U2 network element of the access network is CU-U.

TABLE 1

NF network element of access network	NF description information
		CU-C 1	CU-C
CU-U 2	CU-U

For example, the NRF network element of the access network queries the NF description information according to the NF type in the first information, and finds the NF description information having the same NF type as that in the first information, and the NF network element corresponding to the NF description information is the target NF network element of the access network. For example, in the first information received by the NRF network element of the access network, the NF type of the target NF network element of the access network is CU-C, and the NRF network element of the access network inquires according to table 1 that the NF network element of the access network with the NF type of CU-C in the NF description information is a CU-C1 network element, thereby determining that the target NF network element of the access network is a CU-C1 network element.

The step S205 is an optional step, and the NRF network element of the access network may also determine the target NF network element of the access network through other manners, which is not limited in the present invention.

Optionally, the NRF network element of the access network may obtain the NF description information through a registration process of the NF network element of the access network. The registration process described above will be further described in conjunction with fig. 3A and 3B.

S207: and the NRF network element of the access network sends the second information to the NRF network element of the core network. Accordingly, the NRF network element of the core network receives the second information from the NRF network element of the access network. The second information includes an identifier of a target NF network element of the access network.

For example, after the NRF network element of the access network determines the target NF network element of the access network according to the first information, the identifier of the target NF network element of the access network may be obtained, and the identifier of the target NF network element of the access network is returned to the NRF network element of the core network through step S207.

S208: the NRF network element of the core network sends the second information to the NF network element of the core network in step S201. Correspondingly, the NF network element of the core network receives the second information from the NRF network element of the core network.

So far, the NF network element of the core network obtains the identifier of the target NF network element of the access network. Through the above identification, the NF network element of the core network can establish a communication connection with the target NF network element and access the service provided by the target NF network element. For example, a communication connection may be established between the NF network element of the core network and the target NF network element by using a Transmission Control Protocol (TCP) and a HyperText Transfer Protocol (HTTP).

In the prior art, because the internal structure of the core network is invisible to the outside, when an NE inside the core network accesses the service of the access network, the NE must interact with the access network through an MME network element. And, the MME network element needs to process the interactive signaling before the service access is realized. This way of relying on a network element to process all interactive signaling increases the signaling processing load of the network element, and the more services are accessed, the greater the load of the network element is, the longer the signaling processing time delay is, thereby causing the service efficiency to be reduced. However, according to the solution of the embodiment of the present invention, the NF network element of the core network may find the target NF network element of the access network of the specific NF type. Then, the NF network element of the core network may directly establish a communication connection with the target NF network element of the access network, and implement access to the network function of the access network. After the connection is established, the NF network element of the core network and the target NF network element of the access network can directly transmit and process the interactive signaling without depending on other network elements. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

Optionally, before step S204, the NRF network element of the core network may perform step S202 as follows. It should be noted that, the present application does not limit the sequence between step S202 and step S203. That is, step S202 may be executed first and then step S203 may be executed, step S203 may be executed first and then step S202 may be executed, or steps S202 and S203 may be executed simultaneously.

S202: and the NRF network element of the core network determines that the NF network element of the core network allows to discover the target NF network element of the access network according to the third information. Wherein the third information is used for indicating the NF type of the NF network element of the access network that the NF network element of the core network allows to be discovered. For example, the third information may also be called discovery policy information. That is, only when the NF network element of the core network allows to discover the target NF network element of the access network, the NRF network element of the core network sends the first information received in step S201 to the NRF network element of the access network.

For example, the third information in the NRF network element of the core network may be as shown in table 2. In the example of table 2, the SMF network element of the core network allows discovery of NF network elements with NF type CU-C in the access network; and the PCF network element of the core network allows discovering the NF network element with the NF type of CU-U or NWDAF in the access network.

TABLE 2

NF network element of core network	NF type of NF network element of access network
		SMF	CU-C
PCF	CU-U，NWDAF

It should be noted that table 2 is only an example, and the third information in the NRF network element of the core network according to the present application is not limited to table 2, and any information that can indicate the NF type of the access network NF network element that the NF network element of the core network allows to discover is within the scope of the present application.

Optionally, if the NRF network element of the core network determines that the NF network element of the core network does not allow to discover the target NF network element of the access network according to the third information, the NRF network element of the core network sends the first termination information to the NF network element of the core network. The first termination information is used for indicating that the NF network element of the core network does not allow to discover the target NF network element of the access network. For example, the first termination information is a cause value: the NF network elements of the core network do not allow discovery of the target NF network elements of the access network.

According to the step S202, by configuring the type of the NF network element of the access network allowed to be discovered by the NF network element of each core network, the access right of the NF network element of the core network can be limited, and the security of communication between the core network and the access network is improved.

Optionally, before step S207, the NRF network element of the access network may perform step S206 as follows.

S206: and the NRF network element of the access network determines that the target NF network element of the access network is allowed to be discovered by the NF network element of the core network according to the fourth information. And the fourth information is used for indicating the NF type of the NF network element of the core network which allows the target NF network element to be discovered. For example, the fourth information may also be called discovery policy information. That is, only in the case that the target NF network element of the access network is allowed to be discovered by the NF network element of the core network, the NRF network element of the access network sends the second information to the NRF network element of the core network.

For example, the fourth information in the NRF network element of the access network may be as shown in table 3. In the example of table 3, the CU-C1 network element of the access network is allowed to be discovered by the network element of which NF type is SMF or PCF in the core network; the NWDAF1 network element of the access network is allowed to be discovered by a network element with the NF type NEF in the core network.

TABLE 3

NF network element of access network	NF type of NF network element of core network
		CU-C 1	SMF，PCF
NWDAF
	1	NEF

It should be noted that table 3 is only an example, and the fourth information in the NRF network element of the access network according to the present application is not limited to table 3, and is within the scope of the present application as long as the fourth information is information capable of indicating the NF type of the NF network element of the core network that allows discovery of the target NF network element.

Optionally, if the NRF network element of the access network determines, according to the fourth information, that the target NF network element of the access network is not allowed to be discovered by the NF network element of the core network, the NRF network element of the access network sends the second termination information to the NRF network element of the core network. Wherein the second termination information is used to indicate that the target NF network element is not allowed to be discovered by the NF network element of the core network. For example, the second termination information is a cause value: the target NF network element is not allowed to be discovered by the NF network element of the core network.

According to the step S206, the NF network elements of which types of core networks are allowed to discover by configuring the NF network elements of each access network can further limit the authority of the core network NF network elements to access the access network NF network elements, thereby further improving the security of communication between the core network and the access network.

It should be noted that step S206 and step S202 may be executed separately or simultaneously. When the step S206 is executed independently, the security performance of the communication system is improved by limiting the authority of the NF network element of the access network on the access network side. When the step S202 is executed independently, the security performance of the communication system is also improved by limiting the authority of the NF network element of the core network on the core network side. When step S206 and step S202 are executed simultaneously, the system security is doubly protected by restricting the authority of the NF network element on the access network and the core network side simultaneously, and the security of communication between the core network and the access network is further improved.

Optionally, in step S207, the identifier of the target NF network element of the access network may be at least one of a network address, a full Domain Name (FQDN), and an agent identifier of the target NF network element of the access network.

For example, the network address may be an IP address of a target NF network element of the access network.

Optionally, the network address may be stored in NF description information of a target NF network element of the access network.

The proxy identification is a unified identification provided by the access network in order to hide the internal topology of the access network. The function of the access network hiding the internal topology structure is the proxy function. For example, the proxy identification may be a network address of the proxy function, or a FQDN of the proxy function.

Optionally, the NRF network element of the access network stores the correspondence between the proxy identifier of the target NF network element of the access network and the target NF network element of the access network. The correspondence relationship may be stored in any one of the following two ways.

In a possible implementation manner, the NRF network element of the access network stores the correspondence with the agent identifier as granularity, for example:

agent identification 1: NF 1, NF 3 …

Agent identification 2: NF 2, NF 4 …

The above examples show that: the network element with the agent identifier 1 at least comprises an NF 1 network element and an NF 3 network element, and the network element with the agent identifier 2 at least comprises an NF 2 network element and an NF 4 network element. Therefore, if the target NF network element of the access network is an NF 2 network element, the identifier of the target NF network element of the access network in the second information may be the agent identifier 2.

In another possible implementation manner, the NRF network element of the access network uses the NF network element as a granularity to store the correspondence. In this implementation, the agent identifier may be stored in NF description information of the target NF network element of the access network, for example:

description information of NF 1 network element: agent identification 1, NF type 1 …

Description information of NF 2 network element: agent identification 2, NF type 2 …

The above examples show that: the agent identification of the NF 1 network element is agent identification 1, the NF type is NF type 1, and both the agent identification 1 and the NF type 1 are stored in the description information of the NF 1 network element; the agent identification of the NF 2 network element is the agent identification 2, the NF type is NF type 2, and both the agent identification 2 and the NF type 2 are stored in the description information of the NF 2 network element.

Alternatively, the agent identifier may also be stored separately from NF description information of the target NF network element of the access network, for example:

NF 1 network element: agent identification 1, first NF description …

NF 2 network element: agent identification 2, second NF description information …

The above examples show that: the agent identification of the NF 1 network element is the agent identification 1, and the agent identification 1 and the first NF description information of the NF 1 network element are independently stored; and the agent identifier of the NF 2 network element is the agent identifier 2, and the agent identifier 2 and the second NF description information of the NF 2 network element are independently stored.

By the method, the NRF network element of the access network provides the proxy address of the access network corresponding to the NF network element of the access network to the NRF network element of the core network, so that the NF network element of the access network can be prevented from being directly accessed by the outside, and the topological structure in the access network is hidden outwards. And the proxy address of the access network can provide network security functions such as a firewall and the like, and can perform security check on access from the outside of the access network and process illegal network attacks, thereby improving the security performance of the access network.

In step S208, when the NRF network element of the core network receives the identifiers of the multiple target NF network elements from the NRF network elements of the multiple access networks through step S207, optionally, the NRF network element of the core network sends the identifiers of the multiple target NF network elements together to the NF network element of the core network in step S201.

For example, the NRF1 network element of the core network receives the identifier of the NF 1 network element of the access network from the NRF 2 network element of the access network, and receives the identifier of the NF 2 network element of the access network from the NRF 3 network element of the access network in step S207. The NRF1 network element of the core network sends the identity of the NF 2 network element and the identity of the NF 3 network element together to the NF network element of the core network.

Therefore, when the NRF network element of the core network receives the identifiers of the target NF network elements through the NRF network elements of the access networks, the NRF network element of the core network can reduce the service processing load of the core network by sending the identifiers of the target NF network elements to the NF network element of the core network, thereby improving the service efficiency.

Based on the embodiment shown in fig. 2, in a scenario where an NF network element of a core network needs to acquire a service of an access network in a specified area due to a service requirement, the following description may be further referred to:

in step S201, optionally, the first information further includes identification information of a target NF network element of the access network, where the identification information includes an area identifier of the target NF network element of the access network.

The area identification of the target NF network element of the access network is used for indicating the area served by the target NF network element. The area identity may be a network area identity; alternatively, it may be a geographical area identification. For example, the network Area identifier may be a Tracking Area Identifier (TAI). The geographic area identification may be represented by GPS coordinates and/or distance. For example, the geographic region identifier may be represented by a combination of a GPS coordinate and a distance of 500 meters to indicate a circular region defined by the GPS coordinate as an origin and a radius of 500 meters. Alternatively, the geographical area identifier may be identified by combining 4 GPS coordinate points to indicate a rectangular area determined by using the 4 GPS coordinate points as vertices.

Optionally, if the area identifier in the first information is a geographic area identifier, the method further includes: and the NRF network element of the core network converts the geographical area identifier into a network area identifier. For example, if the area identifier in the first information is a combination of a GPS coordinate and a distance of 500 meters, and is used to represent a circular area determined by using the GPS coordinate as an origin and using 500 meters as a radius, the NRF network element of the core network converts the geographical area identifier into a TAI to which the circular area belongs.

In step S203, optionally, the NRF network element of the core network determines the NRF network element of the access network according to the first information and the area identifier of the NRF network element of the access network.

For example, the NRF network element of the core network may determine the NRF network element of the access network as follows. The NRF network element of the core network firstly acquires the area identifier of the NRF network element of the access network, and then searches the NRF network element of the access network containing the area identifier in the first information, thereby determining the NRF network element of the access network. For example, the service areas corresponding to the area identifiers in the first information are TAI 1 to TAI 6. If the NRF network element of the core network knows that the area identifiers of the NRF1 network element of the access network are TAI 1-TAI 6, the NRF network element of the access network determined by the NRF network element of the core network is the NRF1 network element. If the NRF network element of the core network knows that the area identifiers of the NRF1 network element of the access network are TAI 1-TAI 4 and the area identifiers of the NRF 2 network element of the access network are TAI5 and TAI 6, the NRF network element of the access network determined by the NRF network element of the core network is an NRF1 network element and an NRF 2 network element.

By the above method, when the NRF network element of the core network corresponds to the NRF network elements of the multiple access networks, the core network may find, according to the area identifier in the first information, the NRF network element of one or more access networks that can provide services in the area specified by the area identifier, so as to send the first information to the NRF network element of the one or more access networks in step S204.

Optionally, the NRF network element of the core network may use any one of the following two implementation manners to obtain the area identifier of the NRF network element of the access network.

In a possible implementation manner, when deploying an NRF network element of an access network, a network management system sends NRF network element information of a core network corresponding to the NRF network element of the access network. And then the NRF network element of the access network sends the area identification of the NRF network element of the access network to the NRF network element of the core network. Therefore, the NRF network element of the core network acquires the area identification of the NRF network element of the access network.

In another possible implementation manner, when the NRF network element of the access network is deployed, the network management system directly sends the area identifier of the NRF network element of the access network to the NRF network element of the core network. Therefore, the NRF network element of the core network acquires the area identification of the NRF network element of the access network.

In the above two implementation manners, the Network Management system may be an Operation Administration and Maintenance (OAM) system, or a Network Slice Subnet Management Function (NSSMF) system.

In step S205, optionally, the NF description information of the NF network element of the access network further includes an area identifier of the NF network element of the access network, and the NRF network element of the access network determines the target NF network element of the access network according to the NF type and the area identifier of the target NF network element in the first information and the NF type and the area identifier in the NF description information of the NF network element of the access network.

The area identification of the NF network element of the access network is used for indicating the area served by the NF network element of the access network. For example, NF description information of the above access network NF network element is shown in table 4. In the example of Table 4, the NF description information of the CU-U1 network element of the access network comprises NF type CU-U and area identification TAI 1; NF description information of a CU-U2 network element of an access network comprises an NF type CU-U and area identifications TAI 1 and TAI 2; the NF description information of the NWDAF1 network element of the access network comprises NF type NWDAF and area identification TAI 1.

TABLE 4

For example, the NRF network element of the access network queries the NF description information according to the NF type and the zone identifier in the first information, finds NF description information that has the same NF type as the first information and contains at least 1 zone identifier in the first information, and then the NF network element corresponding to the NF description information is the target NF network element of the access network. For example, in the first information received by the NRF network element of the access network, the NF type of the target NF network element of the access network is CU-U, and the area identifier is TAI 2. The NRF network element of the access network inquires the NF description information according to table 4, the NF type is CU-U, and the NF network element of the access network having the area identifier TAI2 is a CU-U2 network element, thereby determining that the target NF network element of the access network is a CU-U2 network element. And if the NF type of the target NF network element of the access network is CU-U and the area identifier is TAI 1 in the first information received by the NRF network element of the access network. The NF network element of the access network inquires the NF description information according to table 4, where the NF type is CU-U and the NF network element of the access network with the area identifier TAI 1 includes two network elements CU-U1 and CU-U2, and then the NRF network element of the access network determines that the target NF network element of the access network is two network elements CU-U1 and CU-U2. And if the NF type of the target NF network element of the access network is CU-U and the area identifications are TAI2 and TAI 3 in the first information received by the NRF network element of the access network. The NF network element of the access network inquires the NF description information according to table 4, where the NF type is CU-U, and the NF network element of the access network including at least one of the area identifier TAI2 and TAI 3 includes a CU-U2 network element, and the NRF network element of the access network determines that the target NF network element of the access network is a CU-U2 network element.

In step S207, optionally, the second information further includes an association between an area identifier of a target NF network element of the access network and an identifier of the target NF network element.

Since the NF description information of the target network element may only include part of the area identifier in the first information, the number of the target NF network elements of the access network may be one or more. For example, when there are a plurality of target NF network elements of the access network, the target NF network element of the access network sends the association between the area identifier of the target NF network element and the identifier of the target NF network element to the NRF network element of the core network through the second information. For example, if the area identifiers in the first information are TAI 1 to TAI 4, and the target NF network elements of the access network determined by the NRF network element of the access network are CU-U1 network elements and CU-U2 network elements. The area identifiers of the CU-U1 network element are TAI 1 and TAI2, and the area identifiers of the CU-U2 network element are TAI 3 and TAI 4. The second information may be as shown in table 5, and includes: the identifier of the CU-U1 network element is an identifier 1, and the area identifiers corresponding to the identifier 1 are TAI 1 and TAI 2; the identifier of the CU-U2 network element is identifier 2, and the area identifiers corresponding to identifier 2 are TAI 3 and TAI 4. After receiving the second information, the NRF network element of the core network may establish a communication connection with the CU-U1 network element in a subsequent process, and then access the service provided by the CU-U1 network element in the area identified as TAI 1 and TAI2, and may access the service provided by the CU-U2 network element in the area identified as TAI 3 and TAI 4 by establishing a communication connection with the CU-U2 network element. Therefore, the NRF network element of the core network can access the service provided by the target NF network element of the access network in the area with the area identifications TAI 1-TAI 4.

TABLE 5

According to the method, the NF network element of the core network can find the target NF network element of the access network belonging to the specific NF type in the designated area. In the subsequent process, the NF network element of the core network establishes communication connection with the target NF network element of the access network, and then accesses the service provided by the target NF network element of the access network in the designated area.

Based on the embodiment shown in fig. 2, in the access network, the NF network elements of the same NF type may provide multiple services, and each NF network element having the same NF type may provide one or more of the multiple services. For example, an NF network element with NF type CU-U may provide 3 services: service 1, service 2, and service 3. Two NF network elements CU-U1 and CU-U2 with NF type CU-U are arranged in the access network, and can respectively provide one or more of the 3 services. For example, CU-U1 may provide service 1 services and CU-U2 may provide service 2 and service 3 services. In a scenario that the NF network element of the core network needs to acquire multiple services provided by the NF network element of the access network due to service requirements, the following description may be further referred to:

in step S201, optionally, the first information further includes identification information of a target NF network element of the access network, where the identification information includes a service identifier of the target NF network element of the access network. The service identifier of the target NF network element of the access network is used for indicating the service provided by the target NF network element of the access network. For example, the service identifier of the service for acquiring the number of the user equipments may be denoted as get _ UE _ count service.

In step S205, optionally, the NF description information of the NF network element of the access network further includes a service identifier of the NF network element of the access network, and the NRF network element of the access network determines the target NF network element of the access network according to the NF type and the service identifier of the target NF network element in the first information and the NF type and the service identifier in the NF description information of the NF network element of the access network.

The service identifier of the NF network element of the access network is used to indicate a service provided by the NF network element of the access network. For example, the NF description information described above is shown in table 6. In the example of table 6, the NF description information of the CU-U1 network element of the access network includes the NF type CU-U and the service identities service 1 and service 2; NF description information of CU-U2 network elements of the access network comprises an NF type CU-U and service identifications service 2 and service 3; the NF description information of the NWDAF1 network element of the access network comprises NF type NWDAF and service identification service 4.

TABLE 6

For example, when the NF network element of the core network needs to acquire multiple services provided by the NF network element of the access network with the NF type being CU-U, the NRF network element of the access network queries the NF description information according to the NF type and the service identifier in the first information, finds the NF description information that has the same NF type as the first information and contains all the service identifiers in the first information, and then the NF network element corresponding to the NF description information is the target NF network element of the access network. For example, in the first information received by the NRF network element of the access network, the NF type of the target NF network element of the access network is CU-U, and the service identifiers are service 1 and service 2, the access network queries, according to table 6, that the NF type of the target NF network element of the access network is CU-U and the service identifier of the access network including service 1 and service 2 is CU-U1 network element. And the CU-U2 network element does not contain the service identifier service 1, so that the NRF network element of the access network determines that the target NF network element of the access network only comprises the CU-U1 network element. In step S207, the NRF network element of the access network sends the second information to the NRF network element of the core network. And the second information comprises the identification of the target NF network element of the access network.

When only one target NF network element of the access network is available, the second information comprises an identification of the target NF network element. For example, in table 6 above, if the NRF network element of the access network determines that the target NF network element of the access network is the CU-U1 network element, and the identifier of the CU-U1 network element is identifier 1, the second information sent by the NRF network element of the access network to the NRF network element of the core network includes identifier 1. The identification 1 may be the network address, FQDN, or proxy identification of the CU-U1 network element.

And when a plurality of target NF network elements of the access network are available, the second information comprises the identifications of the target NF network elements. For example, the description information of the NF network elements of the access network is shown in table 7. In the example of table 7, the NF description information of the CU-U1 network element of the access network includes the NF type CU-U and service identities service 1 and service 2; NF description information of CU-U2 network elements of the access network comprises an NF type CU-U and service identifiers service 1 and service 2; the NF description information of the NWDAF1 network element of the access network comprises NF type NWDAF and service identification service 3. In the first information received by the NRF network element of the access network, the NF type of the target NF network element of the access network is CU-U, the service identifiers are service 1 and service 2, and the access network inquires that the NF network element of the access network, which has the NF type of CU-U and the service identifier comprising service 1 and service 2 in the NF description information, is CU-U1 network element and CU-U2 network element according to the table 7. The NRF network element of the access network determines that the target NF network elements of the access network are CU-U1 network elements and CU-U2 network elements. And because the identifier of the CU-U1 network element is identifier 1 and the identifier of the CU-U2 network element is identifier 2, the second information sent by the NRF network element of the access network to the NRF network element of the core network includes identifier 1 and identifier 2. Wherein, the identifier 1 may be a network address, an FQDN, or an agent identifier of the CU-U1 network element; the identification 2 may be the network address, FQDN, or proxy identification of the CU-U2 network element.

TABLE 7

According to the method, the NF network element of the core network can find the target NF network element of the access network which belongs to the specific NF type and can provide a plurality of specific services. And then, the NF network element of the core network establishes communication connection with the target NF network element of the access network so as to access various specific services provided by the target NF network element of the access network.

Optionally, the second information further includes a correlation between a service identifier of a target NF network element of the access network and an identifier of the target NF network element.

For example, when the service identifier of the target NF network element of the access network further includes another service identifier different from the service identifier in the first information, the target NF network element of the access network sends the association between the service identifier of the target NF network element and the identifier of the target NF network element to the NRF network element of the core network through the second information. For example, if the service identifiers in the first information are service 1 and service 2, and the target NF network elements of the access network determined by the NRF network element of the access network are CU-U1 network elements and CU-U2 network elements, where the service identifiers of the CU-U1 network elements are service 1, service 2 and service 3, and the service identifiers of the CU-U2 network elements are service 1 and service 2. Since the service identifier of the CU-U1 network element further includes other service identifiers different from the service identifier in the first information, for example, service 3, the second information may be as shown in table 8, and includes: the identifier of the CU-U1 network element is an identifier 1, and the service identifiers corresponding to the identifier 1 are service 1, service 2 and service 3; the identifier of the CU-U2 network element is an identifier 2, and the service identifiers corresponding to the identifier 2 are service 1 and service 2. Wherein, the identifier 1 may be a network address, an FQDN, or an agent identifier of the CU-U1 network element; the identification 2 may be the network address, FQDN, or proxy identification of the CU-U2 network element.

TABLE 8

According to the method, after the NF network element of the core network obtains the correlation between the service identifier of the target NF network element of the access network and the identifier of the target NF network element, when the NF network element of the core network requests to discover the NF network element of the access network which has the same NF type as the target NF network element and can provide other services again, whether the target NF network element can provide the newly required service is judged through the service identifier in the correlation. If the target NF network element can provide the newly required service, the NF network element of the core network can directly access the target NF network element; and if the target NF network element can not provide the service with the new requirement, the NF network element of the core network sends a request to the NRF network element of the core network. Therefore, signaling interaction in the process that the NF network element of the core network requests to find the target NF network element of the access network can be reduced, and therefore the efficiency of the core network accessing the access network is improved.

Based on the embodiment shown in fig. 2, in a scenario where an NF network element of a core network needs to acquire an access network service supporting a specific network slice due to a service requirement, the following description may be further referred to:

in step S201, optionally, the first information further includes identification information of a target NF network element of the access network, where the identification information includes a network slice identifier corresponding to the target NF network element of the access network, and the network slice identifier is used to indicate a network slice type supported by the target NF network element of the access network. For example, the network slice identity may be S-NSSAI. For example, the access network side lays out the access network NF network elements of CU-U type, such as CU-U1 network elements and CU-U2 network elements, for different types of network slices respectively. The CU-U1 network element supports a mobile broadband type network slice, the mobile broadband type network slice corresponds to S-NSSAI 1, and the network slice identifier of the CU-U1 network element is S-NSSAI 1; the CU-C2 network element supports the network slice with the ultra-low delay type, the network slice with the ultra-low delay type corresponds to S-NSSAI2, and the network slice of the CU-U2 network element is marked as S-NSSAI 2. When the NF network element of the core network wishes to acquire an access network service supporting a network slice of the mobile broadband type, the first information further includes S-NSSAI 1.

In step S205, optionally, the NF description information of the NF network element of the access network further includes a network slice identifier of the NF network element of the access network, and the NRF network element of the access network determines the target NF network element of the access network according to the NF type and the network slice identifier of the target NF network element in the first information and the NF type and the network slice identifier in the NF description information of the NF network element of the access network.

The network slice identifier of the NF network element of the access network is used to indicate the type of the network slice that the NF network element of the access network can provide. For example, the description information of the NF network element of the access network is shown in table 9. In the example of Table 9, the NF description information for the CU-U1 network element of the access network includes the NF type CU-U and the network slice identifier S-NSSAI 1; NF description information of a CU-U2 network element of the access network comprises an NF type CU-U and a network slice identifier S-NSSAI 2; the NF description information of the NWDAF1 network element of the access network comprises NF type NWDAF and network slice identification S-NSSAI 1.

TABLE 9

For example, the NRF network element of the access network queries the NF description information according to the NF type and the network slice identifier in the first information, finds the NF description information that has the same NF type as the first information and contains all network slice identifiers in the first information, and then the NF network element corresponding to the NF description information is the target NF network element of the access network. For example, in the first information received by the NRF network element of the access network, the NF type of the target NF network element of the access network is CU-U, and the network slice identifier is S-NSSAI 2. The access network inquires the NF description information according to the table 9, wherein the NF type is CU-U, and the NF network element of the access network with the network slice identifier of S-NSSAI2 is CU-U2 network element, thereby determining that the target NF network element of the access network is CU-C2 network element.

In step S207, the NRF network element of the access network sends the second information to the NRF network element of the core network. And the second information comprises the identification of the target NF network element of the access network.

When only one target NF network element of the access network is available, the second information comprises an identification of the target NF network element. For example, in table 9 above, if the NRF network element of the access network determines that the target NF network element of the access network is the CU-U2 network element, and the identifier of the CU-U2 network element is identifier 2, the second information sent by the NRF network element of the access network to the NRF network element of the core network includes identifier 2. The identification 2 may be the network address, FQDN, or proxy identification of the CU-U2 network element.

And when a plurality of target NF network elements of the access network are available, the second information comprises the identifications of the target NF network elements. For example, the description information of the NF network elements of the access network is shown in table 10. In the example of Table 10, the NF description information for the CU-U1 network element of the access network includes the NF type CU-U and the network slice identifications S-NSSAI 1 and S-NSSAI 2; NF description information of a CU-U2 network element of the access network comprises an NF type CU-U and network slice identifiers S-NSSAI 1 and S-NSSAI 2; the NF description information of the NWDAF1 network element of the access network comprises NF type NWDAF and network slice identification S-NSSAI 3. In the first information received by the NRF network element of the access network, the NF type of the target NF network element of the access network is CU-U, the network slice identifier is S-NSSAI 1 and S-NSSAI2, the access network inquires that the NF type in the NF description information is CU-U and the NF network element of the access network containing S-NSSAI 1 and S-NSSAI2 is CU-U1 network element and CU-U2 network element according to the table 10. The NRF network element of the access network determines that the target NF network elements of the access network are CU-U1 network elements and CU-U2 network elements. And because the identifier of the CU-U1 network element is identifier 1 and the identifier of the CU-U2 network element is identifier 2, the second information sent by the NRF network element of the access network to the NRF network element of the core network includes identifier 1 and identifier 2. Wherein, the identifier 1 may be a network address, an FQDN, or an agent identifier of the CU-U1 network element; the identification 2 may be the network address, FQDN, or proxy identification of the CU-U2 network element.

Watch 10

According to the method, the NF network element of the core network can find the target NF network element of the access network which belongs to the specific NF type and can support the specific network slice type. And then, the NF network element of the core network establishes communication connection with the target NF network element of the access network so as to access the service supported by the specific network slice.

Optionally, the second information further includes an association between a network slice identifier of a target NF network element of the access network and an identifier of the target NF network element. For example, when the network slice identifier of the target NF network element of the access network further includes another network slice identifier different from the network slice identifier in the first information, the target NF network element of the access network sends the association between the network slice identifier of the target NF network element and the identifier of the target NF network element to the NRF network element of the core network through the second information. For example, if the network slices in the first information are identified as S-NSSAI 1 and S-NSSAI2, and the target NF network elements of the access network determined by the NRF network element of the access network are CU-U1 network elements and CU-U2 network elements, the network slices of the CU-U1 network elements are identified as S-NSSAI 1 and S-NSSAI2, and the network slices of the CU-U2 network elements are identified as S-NSSAI 1, S-NSSAI2, and S-NSSAI 3. Since the network slice id of the CU-U2 network element further includes other network slice ids different from the network slice id in the first information, for example, S-NSSAI 3, the second information may be as shown in table 11, and includes: the CU-U1 network element is marked with an identifier 1, and the network slice identifiers S-NSSAI 1 and S-NSSAI2 corresponding to the identifier 1; the CU-U2 network element is marked with the mark 2, and the network slice marks S-NSSAI 1, S-NSSAI2 and S-NSSAI 3 corresponding to the mark 2.

TABLE 11

According to the method, after the NF network element of the core network obtains the association between the network slice identifier of the target NF network element of the access network and the identifier of the target NF network element, when the NF network element of the core network requests to find the NF network element of the access network which has the same NF type as the target NF network element and supports other network slices again, whether the target NF network element can support the newly required network slice is judged through the network slice identifier in the association. If the target NF network element can support the newly required network slice, the NF network element of the core network can directly access the target NF network element; and if the target NF network element can not support the newly required service, the NF network element of the core network sends a request to the NRF network element of the core network. Therefore, signaling interaction in the process that the NF network element of the core network requests to find the target NF network element of the access network can be reduced, and therefore the efficiency of the core network accessing the access network is improved.

Based on the embodiment shown in fig. 2, the first information may further include identification information, where the identification information may include any two or more of an area identifier, a service identifier, or a network slice identifier, and the NF description information of the access network NF network element also includes two or more identifiers corresponding to the first information. For the scenario in which the first information includes different identification information, the embodiment shown in fig. 2 may also be implemented by combining the methods in the above three scenarios, and the present invention is not limited thereto.

The application also discloses a method for registering the NF network element of the access network to the NRF network element of the access network. Fig. 3A and fig. 3B are two implementation methods for registering an NF network element of an access network with an NRF network element of the access network, respectively.

Fig. 3A is a signaling interaction diagram of registration of an NF network element of an access network with an NRF network element of the access network according to an embodiment of the present application. The method can comprise the following steps:

s301: and the NRF network element of the access network receives the NF description information of the NF network element from the NF network element of the access network. Correspondingly, the NF network element of the access network sends the NF description information to the NRF network element of the access network.

For example, the NF description information of the access network may be configured in an NF network element of the access network by a network management system (e.g., OAM or NSSMF) when the NF network element of the access network is deployed. Specifically, in the process of deploying the NF network elements of the access network (i.e., applying for resources in a virtual environment and implementing installation and operation of the NF network elements), a network management system (e.g., OAM or NSSMF) sends NF description information of the NF network elements and NRF network element information of the access network corresponding to the NF network elements. Therefore, the NF network element of the access network obtains the NF description information and sends the NF description information to the NRF network element of the access network through the registration request message.

Optionally, the NF network element of the access network sends the NF description information to the NRF network element of the access network by invoking the first service. For example, the first service may be a registration service of an NF network element.

Optionally, after step S301, the NRF network element of the access network may perform step S302 as follows.

S302: the NRF network element of the access network stores NF description information of the access network.

For example, after the NRF network element of the access network obtains the NF description information of the CU-C1 network element according to step S301, the NF description information is stored. Similarly, the NRF network element of the access network may obtain and store the NF description information of the CU-U2 network element in a similar manner. Therefore, the NRF network element of the access network stores the NF description information of the CU-C1 network element and the CU-U2 network element in the format of the table 1.

Optionally, after step S302, the NRF network element of the access network may perform the following step S303.

S303: and the NRF network element of the access network sends a first response message to the NF network element of the access network. Accordingly, the NF network element of the access network receives the first response message from the NRF network element of the access network. The first response message is used for indicating that the NF network element registration of the access network is completed.

According to the scheme, the NRF network element of the access network can obtain NF description information of the NF network element of the access network. After receiving the first information, the NRF network element of the access network may find a target NF network element capable of providing a specific service by querying the NF description information.

Fig. 3B is a signaling interaction diagram of another NF network element of an access network registering with an NRF network element of the access network according to the embodiment of the present application. The method can comprise the following steps:

s311: and the NRF network element of the access network receives the NF description information of the NF network element from the network management system. Correspondingly, the NF network element of the access network sends the NF description information to the network management system.

When a network management system (such as OAM or NSSMF) deploys NF network elements of an access network, the network management system sends the NF description information of the deployed NF network elements to an NRF network element of the access network, so that the NRF network element of the access network can obtain the NF description information of the NF network elements of the access network when the NF network elements of each access network are deployed. Optionally, the network management system may further send NRF network element information of the access network corresponding to each NF network element to an NRF network element of the access network.

Optionally, after step S311, the NRF network element of the access network may perform step S312 as follows.

S312: the NRF network element of the access network stores NF description information of the access network.

Step S312 can refer to the description of step S302 in fig. 3A, and is not described herein again.

Optionally, after step S311, the NRF network element of the access network may perform step S313 as follows.

S313: the NRF network element of the access network sends a first response message to the network management system. Accordingly, the network management system receives a first response message from the NRF network element of the access network. The first response message is used for indicating the completion of the NF network element registration of the access network.

According to the above scheme, the NRF network element of the access network can obtain NF description information when the network management system deploys the NF network element of the access network. When the network management system deploys the NF network elements of the access network, the NF description information of a plurality of NF network elements deployed at the same time can be sent to the NRF network element of the access network, so that the efficiency of acquiring the NF description information by the NRF network element of the access network is improved, and the time is saved.

Fig. 4A is a signaling interaction diagram of a NF network element of an access network deregistering with an NRF network element of the access network according to the embodiment of the present application. As shown in fig. 4A, the method may include:

s401: and the NF network element of the access network sends the request information to the NRF network element of the access network. Accordingly, the NRF network element of the access network receives the request information from the NF network element of the access network. The request information is used for requesting to an NRF network element of the access network: and de-registering the NF network element of the access network.

For example, when a certain NF network element of the access network is abnormal, the NF network element of the access network sends request information to an NRF network element of the access network. For example, the request message may be an identification bit, or may be a de-registration request message.

Optionally, the NF network element of the access network requests de-registration from the NRF network element of the access network by invoking the second service. For example, the second service may be a deregistration service.

S402: and the NRF network element of the access network sets the state information of the NF network element of the access network to be in an unavailable state.

The unavailable state of the NF network element of the access network indicates that the NF network element can not provide services for other network elements due to shutdown state or disconnected network connection and the like. And the availability status of an access network NF network element indicates that the NF network element can normally provide services in the network. For example, in the NRF network element of the access network, the status information of the NF network element of the access network is shown in table 12. In the example of table 12, the state information "0" indicates that the NF network element of the access network is in the unavailable state, and the state information "1" indicates that the NF network element of the access network is in the available state. In Table 12, the state of the CU-C1 network element is available and the state of the CU-U1 network element is not available.

TABLE 12

NF network element of access network	Status of NF network element
		CU-C 1	1
CU-U 1	0

For example, if the CU-C1 network element sends a request message to the NRF network element of the access network, or the CU-C1 network element invokes the second service, the NF network element of the access network sets the state of CU-C1 to "0", as shown in table 13.

Watch 13

NF network element of access network	Status of NF network element
		CU-C 1	0
CU-U 1	0

Optionally, the NRF network element of the access network may delete NF description information of the NF network element of the access network, for example, NF description information of CU-C1.

Optionally, after step S402, the NRF network element of the access network may perform step S403 as follows.

S403: and the NRF network element of the access network sends a second response message to the NF network element of the access network. Accordingly, the NF network element of the access network receives the second response message from the NRF network element of the access network. The second response message is used for indicating that the NF network element of the access network completes the de-registration.

According to the scheme, a certain NF network element which is abnormal and cannot normally work in the access network requests the NRF network element of the access network to register, so that the NRF network element of the access network can know which NF network element of the access network is temporarily unavailable, and the unavailable NF network element does not need to be compared when the NRF network element of the access network searches for the target NF network element, so that the working load of the NRF network element of the access network is reduced, and the service efficiency is improved.

Fig. 4B is a signaling interaction diagram of another NF network element of an access network deregistering with an NRF network element of the access network according to the embodiment of the present application. The method can comprise the following steps:

s411: and the network management system sends the request information to the NRF network element of the access network. Accordingly, the NRF network element of the access network receives the request information from the network management system. The request message includes an identifier of the NF network element of the at least one unregistered access network, and is used to request, from an NRF network element of the access network: and de-registering the NF network element of the access network.

For example, when the network management system does not need to use NF network elements of some access networks temporarily, the network management system sends the identifications of the NF network elements of the plurality of unneeded access networks to the NRF network elements of the access networks together through the request information. The request information is used for requesting to an NRF network element of the access network: and deregistering the NF network elements of the plurality of access networks. For example, the request message may be an identification bit, or may be a de-registration request message.

S412: and the NRF network element of the access network sets the state information of the NF network element of the access network to be in an unavailable state.

Optionally, when the request information received by the NRF network element of the access network through step S411 includes the identifiers of the multiple access network NF network elements, the NRF network element of the access network may set the state information of the multiple access network NF network elements to an unavailable state at the same time; or, the NRF network element of the access network may delete the NF description information of the multiple access network NF network elements at the same time.

Step S412 can refer to the description of step S402 in fig. 4A, and is not described herein again.

Optionally, after step S412, the NRF network element of the access network may perform step S413 as follows.

S413: and the NRF network element of the access network sends a second response message to the network management system. Correspondingly, the NF network element of the access network receives the second response message from the network management system. The second response message is used for indicating that the NF network element of the access network completes the de-registration.

According to the scheme, when the network management system does not need to use the NF network element of a certain access network temporarily, the network management system can enable the NRF network element of the access network to know which NF network element of the access network is temporarily unavailable by requesting to register the NRF network element of the access network, and then when the NRF network element of the access network searches for the target NF network element, the unavailable NF network element does not need to be compared, so that the workload of the NRF network element of the access network is reduced, and the service efficiency is improved. In addition, the network management system can simultaneously register the NF network elements of a plurality of access networks, so that the efficiency of the NRF network element of the access network for registering the NF network elements of the access networks is improved, and the time is saved.

Fig. 5 is a flowchart of a method for discovering an NF network element of a core network by an NF network element of an access network according to an embodiment of the present application. The method can be used for the NF network element of the access network in a scene that the NF network element of the core network with a specific NF type needs to be found due to service requirements. The core network NF network element to be discovered by the access network NF network element may also be called a target NF network element of the core network. For example, the NF network element of the access network may be any one of NWDAF 111, DU 113, or CU 114 in fig. 1 (or CU-C1141 in CU 114 or CU-U1142 in CU 114). The target NF network element of the core network may be any one of NSSF102, NEF 103, PCF 104, UDM 105, AF 106, AUSF 107, AMF 108, NWDAF109, or SMF 110 in fig. 1. For example, when the NWDAF 111 of the access network needs to acquire services of a certain number of sessions from the PCF 104 of the core network, the NWDAF 111 of the access network may first discover the PCF 104 of the core network through the following mechanism, and then obtain the services through the PCF 104 of the core network.

As shown in fig. 5, the method may include:

s501: and the NF network element of the access network sends the first information to the NRF network element of the access network. Accordingly, the NRF network element of the access network receives the first information from the NF network element of the access network. Wherein the first information comprises an NF type of a target NF network element of the core network.

The NF type of the target NF network element of the core network may be represented by a name of the target NF network element of the core network. For example, the NF type of the target NF network element of the core network may be NSSF, NEF, PCF, or the like.

S503: and the NRF network element of the access network sends the first information to the NRF network element of the core network. Accordingly, the NRF network element of the core network receives the above-mentioned first information from the NRF network element of the access network.

For example, when the NRF network element of the access network is deployed, the network management system sends information of the NRF network element of the core network corresponding to the NRF network element of the access network. Thus, the NRF network element of the access network knows the NRF network element of the core network corresponding to the NRF network element of the access network, and transmits the first information to the NRF network element of the core network.

S504: the NRF network element of the core network determines a target NF network element of the core network.

For example, the NRF network element of the core network determines the target NF network element of the core network according to the first information and the NF description information of the NF network element of the core network. The NF description information of the NF network element of the core network includes an NF type of the NF network element of the core network. For example, the NRF network element of the core network queries the NF description information according to the NF type in the first information, and finds the NF description information having the same NF type as that in the first information, and the NF network element corresponding to the NF description information is the target NF network element of the core network.

The above NRF network element of the core network determines the target NF network element of the core network in a similar manner to the NRF network element of the access network, which can refer to the description of step S205 in fig. 2.

The above step S504 is an optional step. The NRF network element of the core network may also determine the NF network element of the core network by other manners, which is not limited herein.

S506: and the NRF network element of the core network sends the second information to the NRF network element of the access network. Accordingly, the NRF network element of the access network receives the second information from the NRF network element of the core network. The second information includes an identifier of a target NF network element of the core network.

The identifier of the target NF network element of the core network is used to select an NF network element that can provide a specific service. For example, the identifier may be an IP address of the NF network element, or an FQDN, or a service identifier, and/or an instance of the NF network element. Or, the second information sent by the NRF network element of the core network may also be a proxy identifier of the core network. The proxy identifier is a unified identifier provided by the core network to hide the internal topology of the core network. The function of the core network hiding the internal topology structure is the proxy function. For example, the proxy identification may be a network address of the proxy function, or a FQDN of the proxy function.

S507: the NRF network element of the access network sends the second information to the NF network element of the access network in step S501. Correspondingly, the NF network element of the access network receives the second information from the NRF network element of the access network.

In the prior art, since the internal structure of the core network is invisible to the outside, when the access network accesses the service provided by the NE inside the core network, the access network must interact with other NEs through the MME network element of the core network. And, the MME network element needs to process the interactive signaling before the service access is realized. This way of relying on a network element to process all interactive signaling increases the signaling processing load of the network element, and the more services are accessed, the greater the load of the network element is, the longer the signaling processing time delay is, thereby causing the service efficiency to be reduced. However, according to the solution of the embodiment of the present invention, the NF network element of the access network may find the target NF network element of the core network of a specific NF type. Then, the NF network element of the access network can directly establish communication connection with the target NF network element of the core network, and access to the network function of the core network is realized. After the connection is established, the NF network element of the access network and the target NF network element of the core network can directly transmit and process the interactive signaling without depending on other network elements. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

Optionally, before step S503, the NRF network element of the core network may perform step S502 as follows. It should be noted that, the present application does not limit the sequence between step S502 and step S503. That is, step S502 may be executed first and then step S503 may be executed, step S503 may be executed first and then step S502 may be executed, or steps S502 and S503 may be executed simultaneously.

S502: and the NRF network element of the access network determines that the NF network element of the access network allows the target NF network element of the core network to be discovered according to the third information. Wherein the third information is used for indicating the NF type of the NF network element of the core network allowed to be discovered by the NF network element of the access network. For example, the third information may also be called discovery policy information.

For example, the third information in the NRF network element of the core network may be as shown in table 14. In the example of table 14, the CU-C1 network element of the access network allows discovery of NF network elements with NF type SMF in the core network; and the CU-U1 network element of the access network allows discovering the NF network element with the NF type of NSSF or PCF in the core network.

TABLE 14

NF network element of access network	NF type of NF network element of core network
		CU-C 1	SMF
CU-U 1	NSSF，PCF

It should be noted that the table 14 is only an example, and the third information in the NRF network element of the access network according to the present application is not limited to the table 14, and any information that can indicate the NF type of the core network NF network element that the NF network element of the access network allows to discover is within the scope of the present application.

Optionally, if the NRF network element of the access network determines that the NF network element of the access network does not allow to discover the target NF network element of the core network according to the third information, the NRF network element of the access network sends the first termination information to the NF network element of the access network. Wherein the first termination information is used for indicating that the NF network element of the access network does not allow to discover the target NF network element of the core network. For example, the first termination information is a cause value: the NF network elements of the access network do not allow discovery of the target NF network elements of the core network.

According to the step S502, the access right of the NF network element of the access network can be restricted by configuring the type of the NF network element of the core network that the NF network element of each access network allows to be discovered, and the security of communication between the access network and the core network is improved.

Optionally, before step S506, the NRF network element of the core network may perform the following step S505.

S505: and the NRF network element of the core network determines that the target NF network element of the core network is allowed to be discovered by the NF network element of the access network according to the fourth information. And the fourth information is used for indicating the NF type of the NF network element of the access network allowing to discover the target NF network element. For example, the fourth information may also be called discovery policy information.

For example, the fourth information in the NRF network element of the core network may be as shown in table 15. In the example of Table 15, the SMF network elements of the core network are allowed to be discovered by network elements with NF type CU-C or CU-U in the access network; and the NWDAF network element of the core network is allowed to be discovered by a network element with NF type of CU-C in the access network.

Watch 15

NF network element of core network	NF type of NF network element of access network
		SMF	CU-C，CU-U
NWDAF	CU-C

It should be noted that the table 15 is only an example, and the fourth information in the NRF network element of the core network according to the present application is not limited to the table 15, and any information that can indicate the NF type of the NF network element of the access network that allows discovery of the target NF network element is within the scope of the present application.

Optionally, if the NRF network element of the core network determines that the target NF network element of the core network is not allowed to be found by the NF network element of the access network according to the fourth information, the NRF network element of the core network sends the second termination information to the NRF network element of the access network. Wherein the second termination information is used for indicating that the target NF network element is not allowed to be discovered by the NF network element of the access network. For example, the second termination information is a cause value: the target NF network element is not allowed to be discovered by the NF network element of the access network.

According to the step S505, the NF network elements of each core network are configured to allow discovery by the NF network elements of which types of access networks, so that the access authority of the NF network elements of the access networks to the NF network elements of the core networks can be further limited, thereby further improving the security of communication between the access networks and the core networks.

Step S505 and step S502 may be executed separately or simultaneously. When step S505 is executed separately, the security performance of the communication system is improved by limiting the authority of the NF network element of the core network on the core network side. When the step S502 is executed independently, the security performance of the communication system is also improved by limiting the authority of the NF network element of the access network on the access network side. When step S505 and step S502 are executed simultaneously, the security of the system is doubly protected by restricting the authority of the NF network element on the core network and the access network side simultaneously, so that the security of the communication between the core network and the access network is further improved.

Based on the embodiment shown in fig. 5, in a scenario where an NF network element of an access network needs to acquire a service of a core network in a specified area due to a service requirement, the following description may be further referred to:

in step S501, optionally, the first information further includes identification information of the core network, where the identification information includes an area identifier of a target NF network element of the core network.

For example, the area identifier may be a TAI.

In step S504, optionally, the NF description information of the NF network element of the core network further includes an area identifier of the NF network element of the core network, and the NRF network element of the core network determines the target NF network element of the core network according to the NF type and the area identifier of the target NF network element in the first information and the NF type and the area identifier in the NF description information of the NF network element of the core network.

The above NRF network element of the core network determines the target NF network element of the core network in a similar manner to the NRF network element of the access network, and reference may be made to the description in the step S205 in the embodiment of fig. 2 in the scenario where the NF network element of the core network obtains the service of the access network in the specified area.

In step S506, optionally, the second information further includes an association between an area identifier of a target NF network element of the core network and an identifier of the target NF network element.

The above-mentioned manner in which the NRF network element of the core network sends the second information to the NRF network element of the access network is similar to the manner in which the NRF network element of the access network sends the second information to the NRF network element of the core network, and reference may be made to the description in the step S207 in the embodiment of fig. 2 in the scenario that the NF network element of the core network obtains the service of the access network in the specified area.

According to the method, the NF network element of the access network can find the target NF network element of the core network belonging to the specific NF type in the designated area. In the subsequent process, the NF network element of the access network establishes communication connection with the target NF network element of the core network, and then accesses the service provided by the target NF network element of the core network in the designated area.

Based on the embodiment shown in fig. 5, in the core network, NF network elements of the same NF type may provide multiple services, and each NF network element having the same NF type may provide one or more of the multiple services. For example, an NF network element with an NF type of SMF may provide 3 services: session establishment service, session update service, and session deletion service. Two NF network elements SMF 1 and SMF 2 with NF type SMF are deployed in the access network, and they can respectively provide one or more of the above-mentioned 3 services. For example, SMF 1 may provide session establishment services and SMF 2 may provide 3 services of session establishment, session update and session deletion. In a scenario that the NF network element of the access network needs to acquire multiple services provided by the NF network element of the core network due to service requirements, the following description may be further referred to:

in step S501, optionally, the first information further includes identification information of a target NF network element of the core network, where the identification information includes a service identifier of the target NF network element of the core network. The service identifier of the target NF network element of the core network is used to indicate a service provided by the target NF network element of the core network.

In step S504, optionally, the NF description information of the NF network element of the core network further includes a service identifier of the NF network element of the core network, and the NRF network element of the core network determines the target NF network element of the core network according to the NF type and the service identifier of the target NF network element in the first information and the NF type and the service identifier in the NF description information of the NF network element of the core network.

The above NRF network element of the core network determines the target NF network element of the core network in a similar manner to the NRF network element of the access network, and reference may be made to the description in step S205 in the embodiment of fig. 2 in the scenario where the NF network element of the core network obtains multiple services provided by the NF network element of the access network.

In the above step 506, the NRF network element of the core network sends the second information to the NRF network element of the access network. And the second information comprises the identification of the target NF network element of the core network.

According to the method, the NF network element of the access network can find the target NF network element of the core network which belongs to a specific NF type and can provide a plurality of specific services. And then, the NF network element of the access network establishes communication connection with the target NF network element of the core network so as to access various specific services provided by the target NF network element of the core network.

Optionally, the second information further includes a correlation between a service identifier of a target NF network element of the core network and an identifier of the target NF network element.

The above-mentioned manner in which the NRF network element of the core network sends the second information to the NRF network element of the access network is similar to the manner in which the NRF network element of the access network sends the second information to the NRF network element of the core network, and reference may be made to the description in step S207 in the embodiment of fig. 2 in the scenario that the NF network element of the core network obtains multiple services provided by the NF network element of the access network.

According to the method, after the NF network element of the access network obtains the correlation between the service identifier of the target NF network element of the core network and the identifier of the target NF network element, when the NF network element of the access network requests to find the NF network element of the core network which has the same NF type as the target NF network element and can provide other services again, whether the target NF network element can provide the newly required service is judged through the service identifier in the correlation. If the target NF network element can provide the newly required service, the NF network element of the access network can directly access the target NF network element; and if the target NF network element can not provide the service with the new requirement, the NF network element of the access network sends a request to the NRF network element of the access network. Therefore, the signaling interaction in the process that the NF network element of the access network requests to find the target NF network element of the core network can be reduced, and the efficiency of the access network accessing the core network is improved.

Based on the embodiment shown in fig. 5, in a scenario where an NF network element of an access network needs to acquire a core network service supporting a specific network slice due to a service requirement, the following description may be further referred to:

in the step S501, optionally, the first information further includes identification information of a target NF network element of the core network, where the identification information includes a network slice identifier corresponding to the target NF network element of the core network, and the network slice identifier is used to indicate a network slice type supported by the target NF network element of the core network. For example, the network slice identity may be S-NSSAI.

In step S504, optionally, the NF description information of the NF network element of the core network further includes a network slice identifier of the NF network element of the core network, and the NRF network element of the core network determines the target NF network element of the core network according to the NF type and the network slice identifier of the target NF network element in the first information and the NF type and the network slice identifier in the NF description information of the NF network element of the core network.

The above NRF network element of the core network determines the target NF network element of the core network in a similar manner to the NRF network element of the access network, and reference may be made to the description in step S205 in the embodiment of fig. 2 in the context of acquiring the access network service supporting the specific network slice by the NF network element of the core network.

According to the method, the NF network element of the access network can find the target NF network element of the core network which belongs to the specific NF type and can support the specific network slice type. And then, the NF network element of the access network establishes communication connection with the target NF network element of the core network so as to access the service supported by the specific network slice.

In step S506, optionally, the second information further includes an association between a network slice identifier of the target NF network element of the core network and an identifier of the target NF network element.

The above-mentioned manner in which the NRF network element of the core network sends the second information to the NRF network element of the access network is similar to the manner in which the NRF network element of the access network sends the second information to the NRF network element of the core network, and reference may be made to the description in the step S207 in the embodiment of fig. 2 in the context of the NF network element of the core network acquiring the access network service supporting the specific network slice.

According to the method, after the NF network element of the access network obtains the association between the network slice identifier of the target NF network element of the core network and the identifier of the target NF network element, when the NF network element of the access network requests to find the NF network element of the core network which has the same NF type as the target NF network element and supports other network slices again, whether the target NF network element can support the newly required network slice is judged through the network slice identifier in the association. If the target NF network element can support the newly required network slice, the NF network element of the access network can directly access the target NF network element; and if the target NF network element can not support the newly required service, the NF network element of the access network sends a request to the NRF network element of the access network. Therefore, the signaling interaction in the process that the NF network element of the access network requests to find the target NF network element of the core network can be reduced, and the efficiency of the access network accessing the core network is improved.

Based on the embodiment shown in fig. 5, the first information may include identification information, where the identification information may include any two or more of an area identifier, a service identifier, or a network slice identifier, and the NF description information of the core network NF network element also includes two or more identifiers corresponding to the first information. For the scenario in which the first information includes different identification information, the embodiment shown in fig. 5 may also be implemented by combining the methods in the above three scenarios, and the present invention is not limited thereto.

Fig. 6 is a flowchart of a communication method according to an embodiment of the present application. The method can be used for a scene that the NF network element of the core network needs to discover the NF network element of the access network of a specific NF type due to service requirements; the method can also be used in the scenario that the NF network element of the core network of a specific NF type needs to be discovered due to service requirements of the NF network element of the access network.

For example, when the NF network element of the core network needs to discover an NF network element of the access network of a specific NF type due to a service requirement, the first NF network element, the first NRF network element, and the second NRF network element are respectively used to execute various functions of the NF network element of the core network, the NRF network element of the core network, and the NRF network element of the access network in fig. 2. That is, the first NF network element may be any one of NSSF102, NEF 103, PCF 104, UDM 105, AF 106, AUSF 107, AMF 108, NWDAF109, or SMF 110 in fig. 1. The first NRF network element may be the NRF network element 101 of the core network in fig. 1. The target NF network element may be any one of NWDAF 111, DU 113, or CU 114 in fig. 1 (or CU-C1141 in CU 114 or CU-U network element 1142 in CU 114); the second NRF network element may be the NRF network element 112 of the access network in fig. 1.

Or, when the NF network element of the access network needs to discover the NF network element of the core network of a specific NF type due to a service requirement, the first NF network element, the first NRF network element, and the second NRF network element are respectively used to execute various functions of the NF network element of the access network, the NRF network element of the access network, and the NRF network element of the core network in fig. 5. That is, the first NF network element may be any one of NWDAF 111, DU 113, or CU 114 in fig. 1 (or CU-C1141 in CU 114 or CU-U network element 1142 in CU 114); the first NRF network element may be the NRF network element 112 of the access network of fig. 1; the target NF network element may be any one of NSSF102, NEF 103, PCF 104, UDM 105, AF 106, AUSF 107, AMF 108, NWDAF109, or SMF 110 in fig. 1; the second NRF network element may be the NRF network element 101 of the core network in fig. 1.

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

s601: the first NF network element sends the first information to the first NRF network element. Accordingly, the first NRF network element receives the first information from the first NF network element. Wherein the first information comprises the NF type of the target NF network element.

Specifically, step S601 may refer to the description of step S201 in fig. 2 or step S501 in fig. 5, which is not repeated herein.

S603: when the first NRF network element is an NRF network element of a core network and the second NRF network element is an NRF network element of an access network, the first NRF network element determines the second NRF network element.

Specifically, step S603 may refer to the description of step S203 in fig. 2, and is not repeated here.

The above step S603 is an optional step. The first NRF network element may also determine the second NRF network element by other manners, and the invention is not limited thereto.

S604: and the first NRF network element sends the first information to the second NRF network element. Correspondingly, the second NRF network element receives the first information from the first NRF network element.

Specifically, step S604 may refer to the description of step S204 in fig. 2 or step S503 in fig. 5, and is not described herein again.

S605: the second NRF network element determines a target NF network element.

Specifically, step S605 may refer to the description of step S205 in fig. 2 or step S504 in fig. 5, which is not repeated herein.

S607: the second NRF network element sends the second information to the first NRF network element. Accordingly, the first NRF network element receives the second information from the second NRF network element. The second information includes an identifier of the target NF network element.

Specifically, step S607 may refer to the description of step S207 in fig. 2 or step S506 in fig. 5, which is not described herein again.

S608: the first NRF network element sends the second information to the first NF network element in step S601. Correspondingly, the first NF network element receives the second information from the first NRF network element.

Specifically, step S608 may refer to the description of step S208 in fig. 2 or step S507 in fig. 5, and is not repeated herein.

In the prior art, because the internal structure of the core network is invisible to the outside, the NE inside the core network must interact with the access network through the MME network element. And, the MME network element needs to process the interactive signaling before the service access is realized. This way of relying on a network element to process all interactive signaling increases the signaling processing load of the network element, and the more services are accessed, the greater the load of the network element is, the longer the signaling processing time delay is, thereby causing the service efficiency to be reduced. However, according to the scheme of the embodiment of the present invention, the NF network element of the core network may find the target NF network element of the access network of the specific NF type, and the NF network element of the access network may find the target NF network element of the core network of the specific NF type. Then, the NF network element of the core network can directly establish communication connection with the target NF network element of the access network, and realize mutual access of network functions. After the connection is established, the NF network element of the core network and the target NF network element of the access network can directly transmit and process the interactive signaling without depending on other network elements. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

Optionally, before step S604, the first NRF network element may perform step S602 as follows.

S602: and the first NRF network element determines that the first NF network element allows the target NF network element to be discovered according to the third information. Wherein, the third information is used to indicate the NF types of the NF network elements that the first NF network element allows to be discovered.

Specifically, step S602 may refer to the description of step S202 in fig. 2 or step S502 in fig. 5, and is not repeated herein.

According to the step S602, the access right of the NF network element of the core network to the NF network element of the access network can be restricted, and the access right of the NF network element of the access network to the NF network element of the core network can be restricted, so that the security of communication between the core network and the access network is improved.

Optionally, before step S607, the second NRF network element may perform step S606 as follows.

S606: and the second NRF network element determines that the target NF network element is allowed to be discovered by the first NF network element according to fourth information, wherein the fourth information is used for indicating the NF type of the NF network element which is allowed to discover the target NF network element.

Specifically, step S606 may refer to the description of step S206 in fig. 2 or step S505 in fig. 5, which is not repeated herein.

According to the step S606, the communication security between the core network and the access network is further improved by further limiting the permission of the core network NF to access the access network NF and the permission of the access network NF to access the core network NF.

It should be noted that step S606 and step S602 may be executed separately or simultaneously. When the step S606 is executed alone or the step S602 is executed alone, the security performance of the communication system is improved by limiting the authority of the NF network element on a single side of the core network or the access network. When step S606 and step S602 are executed simultaneously, the permission of the NF network element can be restricted simultaneously on both sides of the core network and the access network, so that the system security is protected doubly, and the security of the communication between the core network and the access network is further improved.

In the embodiments provided in the present application, the schemes of the communication method provided in the embodiments of the present application are introduced from the perspective of each network element itself and from the perspective of interaction between each network element. It is to be understood that each network element, for example, the first NRF network element, the second NRF network element, and the first NF network element, includes a corresponding hardware structure and/or software module for performing each function in order to implement the functions. Those of skill in the art would readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

For example, when the network element implements the corresponding functions through software modules. The communication device may include a receiving module 701 and a transmitting module 703, as shown in fig. 7A. Optionally, the communication device further comprises a processing module 702.

In one embodiment, the communication device may be configured to perform the operations of the first NRF network element of fig. 6 described above. For example:

the receiving module 701 is configured to receive first information from a first NF network element, where the first information includes an NF type of a target NF network element, and the target NF network element is an NF network element requested to be discovered by the first NF network element. The sending module 703 is configured to send the first information to the NRF network element. The receiving module 701 is further configured to receive second information from the NRF network element, where the second information includes an identifier of the target NF network element. The sending module 703 is further configured to send the second information to the first NF network element.

Therefore, the NF network element of the core network can find the target NF network element of the access network of the specific NF type, and the NF network element of the access network can also find the target NF network element of the core network of the specific NF type. Then, the NF network elements of the core network may directly establish a communication connection with the NF network elements of the access network and access services to each other. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

Optionally, the processing module 702 is configured to determine, before the sending module sends the first information to the NRF network element, that the first NF network element is allowed to discover the target NF network element according to third information, where the third information is used to indicate an NF type of the NF network element that the first NF network element is allowed to discover.

Optionally, when the communication device is an NRF network element of a core network and the NRF network element is an NRF network element of an access network, the processing module 702 is further configured to determine the NRF network element of the access network before the sending module 703 sends the first information to the NRF network element.

Optionally, before the processing module 702 determines the NRF network element of the access network, the receiving module 701 is further configured to receive, from the network management system or the NRF network element of the access network, an area identifier of the NRF network element of the access network, where the area identifier is used to indicate an area served by the NRF network element of the access network.

In addition, the receiving module 701, the processing module 702, and the sending module 703 in the communication apparatus may also implement other operations or functions of the first NRF network element in the above method, which is not described herein again.

In another embodiment, the communication apparatus shown in fig. 7A may be further configured to perform the operations of the second NRF network element in fig. 6 described above. For example:

the receiving module 701 is configured to receive first information from a network function storage function NRF network element, where the first information includes an NF type of a target network function NF network element. The sending module 703 is configured to send second information to the NRF network element, where the second information includes an identifier of the target NF network element.

Thus, the NRF network element of the core network may receive the identifier of the target NF network element of the access network of the specific NF type from the NRF network element of the access network, and the NRF network element of the access network may receive the identifier of the target NF network element of the core network of the specific NF type from the NRF network element of the core network. Then, the NF network element of the core network may directly establish a communication connection with the target NF network element of the access network and access the service with each other through the identifier of the target NF network element of the access network, and the NF network element of the access network may also directly establish a communication connection with the target NF network element of the core network and access the service with each other through the identifier of the target NF network element of the core network. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

Optionally, the first information further includes an NF type of the first NF network element, and the processing module 702 is configured to determine, before the sending module 703 sends the second information to the NRF network element, that the target NF network element is allowed to be discovered by the first NF network element according to the fourth information and the first information. Wherein the fourth information is used for indicating the NF type allowing the target NF network element to be discovered.

Optionally, when the communication device is an NRF network element of an access network and the NRF network element is an NRF network element of a core network, the processing module 702 is further configured to determine the target NF network element according to the first information and NF description information of the NF network element of the access network before the sending module 703 sends the second information to the NRF network element of the core network. Wherein the NF description information comprises NF type of NF network element of the access network.

Optionally, the first information further includes an area identifier of the target NF network element, the NF description information further includes an area identifier of an NF network element of the access network, and the processing module 702 is configured to determine the target NF network element according to the NF type and the area identifier of the target NF network element in the first information, and the NF type and the area identifier of the NF network element of the access network in the NF description information. Or the first information further includes a service identifier of the target NF network element, the NF description information further includes a service identifier of the NF network element of the access network, and the processing module 802 is configured to determine the target NF network element according to the NF type and the service identifier of the target NF network element in the first information and the NF type and the service identifier of the NF network element of the access network in the NF description information. Or the first information further includes a network slice identifier of the target NF network element, the NF description information further includes a network slice identifier of the NF network element of the access network, and the processing module 702 is configured to determine the target NF network element according to the NF type and the network slice identifier of the target NF network element in the first information, and the NF type and the network slice identifier of the NF network element of the access network in the NF description information.

Optionally, the receiving module 701 is further configured to receive NF description information from the target NF network element. Alternatively, the receiving module 701 is further configured to receive NF description information from the network management system.

Optionally, the receiving module 701 is further configured to receive request information from a network management system or a target NF network element. Wherein the request information is used for requesting, from the NRF network element: and the target NF network element is unregistered. The processing module 702 is further configured to set the status information of the target NF network element to an unavailable status.

In addition, the receiving module 701, the processing module 702, and the sending module 703 in the communication apparatus may also implement other operations or functions of the second NRF network element in the method, which is not described herein again.

In yet another embodiment, the communication apparatus shown in fig. 7A may be further configured to perform the operations of the first NF network element in fig. 6. For example:

the sending module 703 is configured to send NF description information of the communication apparatus to an NRF network element of the access network, where the NF description information includes an NF type of the communication apparatus. The receiving module 701 is configured to receive a first response message from an NRF network element of the access network, where the first response message is used to indicate that the registration of the communication apparatus is completed.

Therefore, the NRF network element of the access network can obtain NF description information of the NF network element of the access network. After receiving the first information, the NRF network element of the access network may find a target NF network element capable of providing the specific service by querying the NF description information.

Optionally, the sending module 703 is further configured to send the request information to an NRF network element of the access network. Wherein the request information is used for requesting to an NRF network element of the access network: the communication device is unregistered. The receiving module 701 is further configured to receive a second response message from an NRF network element of the access network, where the second response message is used to indicate that the deregistration of the communication device is completed.

As shown in fig. 7A, the sending module 703 of the communication apparatus may be further configured to send first information to an NRF network element of the access network, where the first information includes an NF type of a target NF network element of the core network. The receiving module 701 may be further configured to receive second information from an NRF network element of the access network, where the second information includes an identification of the target NF network element.

Thus, the NF network element of the access network may receive the target NF network element of the core network of the particular NF type from the NRF network element of the access network. Then, the NF network element of the access network can directly establish communication connection with the target NF network element of the access network and access services to each other. The service access mode distributes the signaling in the interaction among all network elements for processing, thereby saving the waiting time before the signaling processing and improving the service efficiency.

In addition, the receiving module 701, the processing module 702, and the sending module 703 in the communication apparatus may also implement other operations or functions of the NF network element of the access network in the above method, which is not described herein again.

Fig. 7B shows another possible structure diagram of the communication device involved in the above embodiment. The communication device includes a transceiver 704 and a processor 705, as shown in fig. 7B. For example, the processor 705 may be a general purpose microprocessor, a data processing circuit, an Application Specific Integrated Circuit (ASIC), or a field-programmable gate array (FPGA) circuit. The communication device may also include a memory 706, such as a Random Access Memory (RAM). The memory is for coupling with the processor 705 and holds the necessary computer programs 7061 for the communication device. Optionally, the communication method in the above embodiments further provides a carrier 707, in which a computer program 7071 of the communication apparatus is stored, and the computer program 7071 may be loaded into the processor 705. The carrier may be an optical signal, an electrical signal, an electromagnetic signal, or a computer readable storage medium (e.g., a hard disk). The

computer program

7061 or 7071 described above, when run on a computer (e.g., the processor 705), can cause the computer to perform the methods described above.

For example, in one embodiment, the processor 705 is configured for other operations or functions of the first NRF network element. The transceiver 704 is configured to enable communication between the communication device and the first NF network element/second NRF network element.

In another embodiment, the processor 705 is configured as other operations or functions of the second NRF network element. The transceiver 704 is used to enable communication between the communication device and the first NRF network element/target NF network element/network management system.

For example, the first NRF network element may be an NRF network element of a core network and the second NRF network element may be an NRF network element of an access network, or the first NRF network element may be an NRF network element of an access network and the second NRF network element may be an NRF network element of a core network. That is, in one possible implementation, the processor 705 is configured as other operations or functions of NRF network elements of the core network. The transceiver 704 is used to enable communication between NRF network elements of the core network and NRF network elements of the NF/access networks of the core network. In another possible implementation, the processor 705 is configured as other operations or functions of an NRF network element of the access network. The transceiver 704 is used to enable communication between an NRF network element of the access network and an NF network element of the access network/an NRF network element of the core network.

In another embodiment, the processor 705 is configured to perform the corresponding functions of the first NF network element in the above method by the communication apparatus. The transceiver 704 is used to enable communication between the communication device and the first NRF network element.

For example, the processor 705 is configured to perform the corresponding functions of the NF network elements of the access network in the above method by the communication apparatus. The transceiver 704 is used to enable communication between the communication device and NRF network elements of the access network.

Alternatively, the processor 705 is configured to configure the communication apparatus to perform the corresponding functions of the NF network elements of the core network in the above method. The transceiver 704 is used to enable communication between the communication device and NRF network elements of the core network.

The controller/processor for implementing the radio access network devices described above may be a Central Processing Unit (CPU), general purpose processor, Digital Signal Processor (DSP), Application Specific Integrated Circuit (ASIC), Field Programmable Gate Array (FPGA) or other programmable logic device, transistor logic device, hardware component, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. The processor may also be a combination of computing functions, e.g., comprising one or more microprocessors, DSPs, and microprocessors, among others.

The steps of a method or algorithm described in connection with the disclosure herein may be embodied in hardware or in software instructions executed by a processor. The software instructions may consist of corresponding software modules that may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be integral to the processor. The processor and the storage medium may reside in an ASIC. Additionally, the ASIC may reside in a radio access network device. Of course, the processor and the storage medium may reside as discrete components in a radio access network device.

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

The above-mentioned embodiments, objects, technical solutions and advantages of the present invention are further described in detail, it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made on the basis of the technical solutions of the present invention should be included in the scope of the present invention.

Claims

1. A method of communication, comprising:

a first network function storage function network element receives a network function NF type of a target network function network element from the first network function network element, wherein the target network function network element is a network function network element which is requested to be discovered by the first network function network element;

the first network function storage function network element sends the NF type of the target network function network element to a second network function storage function network element;

the first network function storage function network element receives the identification of the target network function network element from the second network function storage function network element;

and the first network function storage function network element sends the identification of the target network function network element to the first network function network element.

2. The method of claim 1, wherein before the first network function storage function network element sends the NF type of the target network function network element to the second network function storage function network element, the method further comprises:

and the first network function storage function network element determines that the first network function network element allows the discovery of the target network function network element according to third information, wherein the third information is used for indicating the NF type of the network function network element allowed to be discovered by the first network function network element.

3. The method according to claim 1 or 2, wherein the first network function storage function network element is a network function storage function network element of a core network, and the second network function storage function network element is a network function storage function network element of an access network.

4. The method of claim 3, further comprising:

and the first network function storage function network element determines the second network function storage function network element.

5. The method of claim 4, further comprising:

the first network function storage function network element receives a first area identifier of the second network function storage function network element from a network management system or the second network function storage function network element, wherein the first area identifier is used for indicating an area served by the second network function storage function network element.

6. The method of any of claims 1 to 5, wherein the receiving, by the first network function storage function network element, the NF type of the target network function network element from the first network function network element comprises:

the first network function storage function network element receives first information from the first network function network element, where the first information includes an NF type of the target network function network element, and a second area identifier, a service identifier, or a network slice identifier of the target network function network element, the second area identifier is used to indicate an area served by the target network function network element, the service identifier is used to indicate a service provided by the target network function network element, and the network slice identifier is used to indicate a network slice type supported by the target network function network element.

7. A communications apparatus, characterized in that the communications apparatus comprises at least one processor configured to execute software instructions to cause the communications apparatus to implement the method of any one of claims 1 to 6.

8. A computer-readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform the method of any of claims 1 to 6.

9. A computer program product comprising instructions which, when run on a computer, cause the computer to perform the method of any one of claims 1 to 6.