CN118803711A - Access method, device and network side equipment - Google Patents

Abstract

The application discloses an access method, an access device and network side equipment, which belong to the technical field of communication, and the access method of the embodiment of the application comprises the following steps: receiving a registration request sent by a terminal, acquiring subscription information of the terminal, establishing N15 connection, determining that the terminal roams, initiating PCF discovery twice to NRF, and sending an AM policy control establishment message to H-PCF through V-PCF to establish AM policy control; and receiving a PDU session establishment message sent by the terminal, if the DNN requested by the terminal is a specific DNN, sending an AM policy control update message to the H-PCF through the V-PCF to obtain a second DNN, and determining a target SMF based on the second DNN to realize that the terminal is accessed to the client side data center nearby. Wherein, the H-PCF needle pre-configures the mapping relation between the service area and the replacement DNN. The application can flexibly select the access of the nearby data center at the enterprise side based on the user visit position.

Description

Access method, device and network side equipment

Technical Field

The present application belongs to the field of communication technology, and specifically relates to an access method, device and network side equipment.

Background Art

5G industry customers set up multiple regions across the country according to their own data center planning. Each region plans a regional center and deploys client-side servers/data centers in the regional center. When industry users roam, how to access the client-side server/data center of the regional center nearby according to the roaming area is a problem that needs to be solved.

In the related technology, when a user signs a contract for a universal data network name, the data network name (Data Network Name, DNN), single network slice selection assistance information (Single Network Slice Selection Assistance Information, S-NSSAI) and other matching parameter services are used to discover the session management function (Session Management Function, SMF) of the user's visit location, and the SMF selects the optimal UPF based on the parameters such as S-NSSAI, DNN, and Tracking Area Identity (Tracking Area Identity, TAI) range that the user plane function (User Plane Function, UPF) is responsible for to achieve business unblocking. When a user signs up for a dedicated data network name or a network-wide data network name, the service platform of the external data network is only connected to specific SMF and UPF. The Access and Mobility Management Function (AMF) needs to perform SMF service discovery to the Network Repository Function (NRF) twice: AMF performs SMF service discovery to NRF for the first time, and matches SMF based on DNN and S-NSSAI, but does not match Preferred-TAI; then AMF performs SMF service discovery to NRF for the second time, and NRF matches the Intermediate Session Management Function (I-SMF) based on S-NSSAI and TAI.

The above-mentioned related technologies either use a general DNN method to select local SMF and UPF nearby, or use a dedicated or full-network DNN to fixedly point to a certain/group of specific SMF and UPF. They cannot flexibly select different data center access node SMFs and UPFs according to the user's access location, resulting in large service delays.

Summary of the invention

The embodiments of the present application provide an access method, an apparatus, and a network-side device, which can solve the problem that the related technology cannot flexibly select different data center access nodes SMF and UPF according to the user's visiting location, resulting in large service delays.

In a first aspect, an access method is provided, the method comprising:

The access and mobility management function AMF receives the registration request sent by the terminal, and obtains the subscription information of the terminal, where the subscription information includes: the specific data network name DNN subscribed by the terminal;

The AMF determines, based on the specific DNN subscribed by the terminal, that a condition for establishing an N15 connection is satisfied, and the AMF establishes an N15 connection;

The AMF determines that the terminal is roaming, initiates two policy control function PCF service discovery processes to the NRF, and obtains information about the visited policy control function V-PCF and the home policy control function H-PCF;

The AMF sends an AM policy control establishment message to the H-PCF through the V-PCF;

The AMF receives an AM policy control establishment response message, the AM policy control establishment response message carries SMF selection indication information, and the SMF selection indication information is used to indicate that the AMF needs to initiate a DNN replacement process when detecting that the terminal has created a new PDU session based on a specific DNN subscribed by the terminal;

The AMF receives a PDU session establishment message sent by the terminal, where the PDU session establishment message carries a first DNN, where the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

The AMF determines that the first DNN is in the specific DNN, and sends an AM policy control update message to the H-PCF through the V-PCF;

The AMF receives an AM policy control update response message, where the AM policy control update response message carries a second DNN;

The AMF determines the target SMF based on the second DNN, and enables the terminal to access the client-side data center nearby through the target SMF;

The second DNN is determined by the V-PCF according to other local strategies and the replacement DNN determined by the H-PCF;

The terminal has previously signed a nearby access service package at the H-PCF, and the H-PCF pre-configures a mapping relationship between each service area and a replacement DNN for each nearby access service package;

The replacement DNN determined by the H-PCF is determined based on the visited area information of the terminal, the operator information accessed by the terminal or the location information of the terminal, and the mapping relationship.

In a second aspect, an access method is provided, the method comprising:

The visited location policy control function V-PCF receives an AM policy control update message sent by the AMF, where the AM policy control update message carries information of the first DNN and the H-PCF, where the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

The V-PCF checks that the information of the H-PCF is valid, and sends a second N24 session request to the H-PCF, where the second N24 session request carries the first DNN and terminal location related information;

The V-PCF receives a second N24 session request response sent by the H-PCF, where the second N24 session request response carries the replacement DNN determined by the H-PCF;

The V-PCF determines a second DNN according to other local strategies and the replacement DNN determined by the H-PCF;

The V-PCF sends an AM policy control update response message to the AMF, where the AM policy control update response message carries the second DNN;

The second DNN is used by the AMF to determine the target SMF, so as to enable the terminal to access the client-side data center nearby through the target SMF;

The terminal has previously signed a nearby access service package at the H-PCF, and the H-PCF pre-configures a mapping relationship between each service area and a replacement DNN for each nearby access service package;

The replacement DNN determined by the H-PCF is determined based on the terminal location related information and the mapping relationship.

In a third aspect, an access method is provided, including:

The home policy control function H-PCF receives a second N24 session request sent by the V-PCF, where the second N24 session request carries the first DNN and terminal location related information; the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

The H-PCF determines, according to the terminal location related information and the preconfigured mapping relationship, a replacement DNN for the terminal to access nearby;

The H-PCF sends a second N24 session request response to the V-PCF, where the second N24 session request response carries the replacement DNN determined by the H-PCF;

Among them, the terminal has previously signed a nearby access service package in the H-PCF; the H-PCF preconfigures the mapping relationship for each nearby access service package, and the mapping relationship is a mapping relationship between each service area and the replacement DNN.

In a fourth aspect, an access method is provided, including:

The session management function SMF receives the specific DNN determined by the home PCF/UDR according to the access location of the terminal and the preconfigured mapping relationship;

The SMF executes the PCC policy based on the specific DNN, and activates the PDU session corresponding to the specific DNN for the terminal when receiving the first event reported by the UPF;

The first event is used to indicate that the destination address in the data message of the general DNN service of the terminal is the address corresponding to the specific DNN;

The terminal has previously signed a contract to activate a PCC policy on the home PCF/UDR of the terminal, and the PCC policy is used to indicate that when a destination address corresponding to a specific DNN is detected in a data message of a general DNN service of the terminal, the specific DNN is activated for the terminal;

The home PCF/UDR pre-configures the mapping relationship between each service area and a specific DNN

In a fifth aspect, an access device is provided, including:

A contract information acquisition unit, configured to receive a registration request sent by a terminal, and acquire contract information of the terminal, wherein the contract information includes: a specific data network name DNN contracted by the terminal;

An N15 establishing unit, configured to determine, based on the specific DNN subscribed by the terminal, that a condition for establishing an N15 connection is satisfied, and establish an N15 connection;

The first PCF service discovery unit is used to determine that the terminal is roaming, initiate two policy control function PCF service discovery processes to the NRF, and obtain information about the visited policy control function V-PCF and information about the home policy control function H-PCF;

A first AM policy control establishment unit, configured to send an AM policy control establishment message to the H-PCF through the V-PCF;

An AM policy control establishment response unit, configured to receive an AM policy control establishment response message, wherein the AM policy control establishment response message carries SMF selection indication information, wherein the SMF selection indication information is used to indicate that the AMF needs to initiate a DNN replacement process when detecting that the terminal has established a new PDU session based on a specific DNN subscribed by the terminal;

A session establishing unit, configured to receive a PDU session establishing message sent by the terminal, wherein the PDU session establishing message carries a first DNN, and the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

An AM policy updating unit, configured to determine that the first DNN is in the specific DNN, and then send an AM policy control update message to the H-PCF through the V-PCF;

An AM policy update response unit, configured to receive an AM policy control update response message, wherein the AM policy control update response message carries a second DNN;

An SMF determining unit is used to determine a target SMF based on the second DNN, and to enable the terminal to access the client-side data center nearby through the target SMF;

The second DNN is determined by the V-PCF according to other local strategies and the replacement DNN determined by the H-PCF;

The terminal has previously signed a nearby access service package at the H-PCF, and the H-PCF pre-configures a mapping relationship between each service area and a replacement DNN for each nearby access service package;

The replacement DNN determined by the H-PCF is determined based on the visited area information of the terminal, the operator information accessed by the terminal or the location information of the terminal, and the mapping relationship.

In a sixth aspect, an access device is provided, including:

A first receiving unit is configured to receive an AM policy control update message sent by the AMF, wherein the AM policy control update message carries information of a first DNN and an H-PCF, wherein the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

A first N24 session establishing unit, configured for the V-PCF to check if the information of the H-PCF is valid, and to send a second N24 session request to the H-PCF, wherein the second N24 session request carries the first DNN and terminal location related information;

A first N24 session response unit, configured to receive a second N24 session request response sent by the H-PCF, where the second N24 session request response carries a replacement DNN determined by the H-PCF;

A DNN decision unit, configured to determine a second DNN according to other local strategies and the replacement DNN determined by the H-PCF;

An AM policy update response sending unit, configured for the V-PCF to send an AM policy control update response message to the AMF, wherein the AM policy control update response message carries the second DNN;

The second DNN is used by the AMF to determine the target SMF, so as to enable the terminal to access the client-side data center nearby through the target SMF;

The terminal has previously signed a nearby access service package at the H-PCF, and the H-PCF pre-configures a mapping relationship between each service area and a replacement DNN for each nearby access service package;

The replacement DNN determined by the H-PCF is determined based on the terminal location related information and the mapping relationship.

In a seventh aspect, an access device is provided, including:

A second receiving unit is configured to receive a second N24 session request sent by the V-PCF, wherein the second N24 session request carries information related to the first DNN and the terminal location; the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

A replacement DNN determining unit, configured to determine a replacement DNN for the terminal to access nearby according to the terminal location related information and a preconfigured mapping relationship;

a replacement DNN sending unit, configured to send a second N24 session request response to the V-PCF, wherein the second N24 session request response carries the replacement DNN determined by the H-PCF;

Among them, the terminal has previously signed a nearby access service package in the H-PCF; the H-PCF preconfigures the mapping relationship for each nearby access service package, and the mapping relationship is a mapping relationship between each service area and the replacement DNN.

In an eighth aspect, an access device is provided, including:

A fourth receiving unit, configured to receive a specific DNN determined by a home PCF/UDR according to an access location of the terminal and a preconfigured mapping relationship;

A first PCC policy execution unit is configured to execute a PCC policy based on the specific DNN, and activate a PDU session corresponding to the specific DNN for the terminal when receiving a first event reported by the UPF;

The first event is used to indicate that the destination address in the data message of the general DNN service of the terminal is the address corresponding to the specific DNN;

The terminal has previously signed a contract to activate a PCC policy on the home PCF/UDR of the terminal, and the PCC policy is used to indicate that when a destination address corresponding to a specific DNN is detected in a data message of a general DNN service of the terminal, the specific DNN is activated for the terminal;

The home PCF/UDR preconfigures a mapping relationship between each service area and a specific DNN.

In the ninth aspect, a network side device is provided, which includes a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the program or instructions are executed by the processor, the steps of the method described in the first aspect, the second aspect, the third aspect, or the fourth aspect are implemented.

In the tenth aspect, a readable storage medium is provided, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of the method described in the first aspect, the second aspect, the third aspect, or the fourth aspect are implemented.

In the eleventh aspect, a chip is provided, comprising a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run a program or instruction to implement the method described in the first aspect, the second aspect, the third aspect, or the fourth aspect.

In the twelfth aspect, a computer program/program product is provided, wherein the computer program/program product is stored in a storage medium, and the program/program product is executed by at least one processor to implement the steps of the method described in the first aspect, the second aspect, the third aspect, or the fourth aspect.

In an embodiment of the present application, by pre-configuring a dedicated DNN replacement strategy in the home PCF, that is, the mapping relationship between the service area and the replacement DNN, in the terminal registration process, when the AMF determines that the terminal is in a roaming state, it initiates two PCF service discovery processes to obtain information about the V-PCF and H-PCF, and then obtains the AM policy from the H-PCF through the V-PCF. When the AMF receives a new PDU session based on a specific DNN by the terminal, it initiates a DNN replacement process to the H-PCF through the V-PCF to obtain the DNN information finally determined by the V-PCF. The AMF uses the DNN information to discover the SMF of the nearest access node, thereby enabling users to access the nearest client-side server or data center. There is no need to configure complex TAC data to support flexible selection of the nearest data center access on the enterprise side based on the user's visit location. When new enterprise needs and changes in the deployment location of the enterprise-side data center are added, there is no need for complex full-network bureau data configuration. When the location of the industry customer data center or the nearest access province changes, the access policy adjustment can be achieved by simply modifying the user's home PCF configuration data. In terms of networking, there are no restrictions such as the need for secondary networking of NRF, and the networking method is more flexible. The network configuration and maintenance data is small, and the user terminal side only configures the dedicated DNN information signed by the enterprise. There is no need to change the DNN information as the customer-side data center area planning changes. This application has no special requirements for the user terminal UE and the enterprise data center side, supports flexible and rapid deployment, and can meet the user's automatic access needs when the customer data center changes, and is highly practical.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a block diagram of a wireless communication system applicable to an embodiment of the present application;

FIG2 is a schematic diagram of one of the flow charts of the access method provided in the embodiment of the present application;

FIG3 is a second flow chart of the access method provided in an embodiment of the present application;

FIG4 is a third flow chart of the access method provided in the embodiment of the present application;

FIG5 is a schematic diagram of a solution for a terminal that has signed a contract for a dedicated DNN or a full-network DNN to access a nearby client-side data center, provided in an embodiment of the present application;

6 is a schematic diagram of signaling interaction during the terminal registration phase in the access method provided in an embodiment of the present application;

7 is a schematic diagram of signaling interaction during the session establishment phase in the access method provided in an embodiment of the present application;

8 is a schematic diagram of signaling interaction of a switching process in an access method provided in an embodiment of the present application;

FIG9 is a fourth flow chart of the access method provided in an embodiment of the present application;

FIG10 is a schematic diagram of a solution for realizing terminal nearby access in a multi-DNN scenario without sensed traffic diversion provided by the present application;

FIG11 is a fifth flow chart of an access method provided in an embodiment of the present application;

FIG12 is a schematic diagram of a structure of an access device provided in an embodiment of the present application;

FIG13 is a second schematic diagram of the structure of the access device provided in an embodiment of the present application;

FIG14 is a third schematic diagram of the structure of the access device provided in an embodiment of the present application;

FIG15 is a fourth structural diagram of an access device provided in an embodiment of the present application;

FIG16 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application;

FIG17 is a schematic diagram of the structure of a network side device provided in an embodiment of the present application.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of this application.

The terms "first", "second", etc. in this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of one type, and the number of objects is not limited, for example, the first object can be one or more. In addition, "or" in this application represents at least one of the connected objects. For example, "A or B" covers three schemes, namely, Scheme 1: including A but not including B; Scheme 2: including B but not including A; Scheme 3: including both A and B. The character "/" generally indicates that the objects associated with each other are in an "or" relationship.

The term "indication" in this application can be a direct indication (or explicit indication) or an indirect indication (or implicit indication). A direct indication can be understood as the sender explicitly informing the receiver of specific information, operations to be performed, or request results in the sent indication; an indirect indication can be understood as the receiver determining the corresponding information according to the indication sent by the sender, or making a judgment and determining the operation to be performed or the request result according to the judgment result.

It is worth noting that the technology described in the embodiments of the present application is not limited to the Long Term Evolution (LTE)/LTE-Advanced (LTE-A) system, but can also be used in other wireless communication systems, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-carrier Frequency Division Multiple Access (SC-FDMA) or other systems. The terms "system" and "network" in the embodiments of the present application are often used interchangeably, and the described technology can be used for the above-mentioned systems and radio technologies as well as other systems and radio technologies. The following description describes a new radio (NR) system for example purposes, and NR terms are used in most of the following descriptions, but these technologies can also be applied to systems other than NR systems, such as ^6th Generation (6G) communication systems.

FIG1 shows a block diagram of a wireless communication system applicable to an embodiment of the present application. The wireless communication system includes a terminal 11 and a network side device 12. The terminal 11 may be a mobile phone, a tablet computer (Tablet Personal Computer), a laptop computer (Laptop Computer), a notebook computer, a personal digital assistant (Personal Digital Assistant, PDA), a handheld computer, a netbook, an ultra-mobile personal computer (Ultra-mobile Personal Computer, UMPC), a mobile Internet device (Mobile Internet Device, MID), an augmented reality (Augmented Reality, AR), a virtual reality (Virtual Reality, VR) device, a robot, a wearable device (Wearable Device), an aircraft (flight vehicle), a vehicle user equipment (VUE), a shipborne equipment, a pedestrian terminal (Pedestrian User Equipment, PUE), a smart home (a home appliance with wireless communication function, such as a refrigerator, a television, a washing machine or furniture, etc.), a game console, a personal computer (Personal Computer, PC), a teller machine or a self-service machine and other terminal side devices. Wearable devices include: smart watches, smart bracelets, smart headphones, smart glasses, smart jewelry (smart bracelets, smart bracelets, smart rings, smart necklaces, smart anklets, smart anklets, etc.), smart wristbands, smart clothing, etc. Among them, the vehicle-mounted device can also be called a vehicle-mounted terminal, a vehicle-mounted controller, a vehicle-mounted module, a vehicle-mounted component, a vehicle-mounted chip or a vehicle-mounted unit, etc. It should be noted that the specific type of the terminal 11 is not limited in the embodiment of the present application. The network side device 12 may include an access network device or a core network device, wherein the access network device may also be referred to as a radio access network (Radio Access Network, RAN) device, a radio access network function or a radio access network unit. The access network device may include a base station, a wireless local area network (Wireless Local Area Network, WLAN) access point (Access Point, AS) or a wireless fidelity (Wireless Fidelity, WiFi) node, etc. Among them, the base station may be referred to as a Node B (NB), an evolved Node B (eNB), a next generation Node B (gNB), a New Radio Node B (NR Node B), an access point, a Relay Base Station (RBS), a Serving Base Station (SBS), a Base Transceiver Station (BTS), a radio base station, a radio transceiver, a Basic Service Set (BSS), an Extended Service Set (ESS), a Home Node B (HNB), a Home Evolved Node B, a Transmission Reception Point (TRP) or other appropriate terms in the field. As long as the same technical effect is achieved, the base station is not limited to specific technical terms. It should be noted that in the embodiments of the present application, only the base station in the NR system is used as an example for introduction, and the specific type of the base station is not limited.

The core network device may include, but is not limited to, at least one of the following: a core network node, a core network function, a mobility management entity (Mobility Management Entity, MME), an access mobility management function (Access and Mobility Management Function, AMF), a session management function (Session Management Function, SMF), a user plane function (User Plane Function, UPF), a policy control function (Policy Control Function, PCF), a policy and charging rules function unit (Policy and Charging Rules Function, PCRF), an edge application service discovery function (Edge Application Server Discovery Function, EASDF), a unified data management (Unified Data Management, UDM), a unified data storage (Unified Data Repository, UDR), a home user server (Home Subscriber Server, HSS), a centralized network configuration (CNC), a network storage function (Network Repository Function, NRF), a network exposure function (Network Exposure Function, NEF), a local NEF (Local NEF, or L-NEF), and a binding support function (Binding Support Function, BSF), application function (Application Function, AF), etc. It should be noted that in the embodiment of the present application, only the core network device in the NR system is introduced as an example, and the specific type of the core network device is not limited.

The access method, apparatus and network side equipment provided in the embodiments of the present application are described in detail below through some embodiments and their application scenarios in combination with the accompanying drawings.

Figure 2 is one of the flow charts of the access method provided in the embodiment of the present application. As shown in Figure 2, the access method uses the access and mobility management function AMF as the execution subject. It should be noted that in order to clearly describe the access method provided in the embodiment of the present application, the AMF is used as the execution subject for description, and the access method provided in the embodiment of the present application can also be applied to other network elements that can execute the steps of the access method, and the present application does not limit this.

The method comprises the following steps:

Step 200: The access and mobility management function AMF receives a registration request sent by the terminal, and obtains the contract information of the terminal, where the contract information includes: a specific data network name DNN contracted by the terminal;

The access method provided by this application can meet the needs of the following application scenarios: 5G industry customers divide the country into multiple regions according to the data center planning on their side, and set up a regional center in each region to deploy client-side servers/data centers. When industry users roam, they access the client-side server/data center of the regional center to which they belong according to the area to which they roam. The user terminal side is only configured with the dedicated or full-network DNN or general DNN information signed by the enterprise, and there is no need to change the DNN information as the client-side data center changes. Off-site disaster recovery of customer data centers can be supported on demand.

In the access method provided by the present application, the terminal has pre-signed a local access service package at the Home Policy Control Function (H-PCF), and the H-PCF pre-configures a mapping relationship between each service area and the replacement DNN for each local access service package.

Subsequently, PCF identifies the terminal access province/region information through AMF Globally Unique AMF Identifier (GUAMI) or TA and other information. For international roaming scenarios, in addition to GUAMI, terminal access operator information or location information can also be identified based on fields such as Serving Public Land Mobile Network (PLMN), so as to determine the replacement DNN based on the mapping relationship pre-configured locally by PCF, and achieve access to the nearest enterprise data center.

The configuration example is as follows:

Table 1 Mapping relationship of PCF local preconfiguration

Different replacement DNNs for selecting the nearest access node are planned according to the enterprise regional division and the corresponding multiple access nodes (for example, if the enterprise has two access points in Beijing and Guangdong, two dedicated DNNs or a specific full-network DNN (without the province suffix) are allocated, such as Beijing corresponding to DNN.bj or a full-network DNN1, Guangdong corresponding to DNN.gd or a full-network DNN2.

If remote disaster recovery is considered, replacing the DNN may include replacing the active DNN and replacing the standby DNN. The following is an example of a remote disaster recovery scenario configuration:

Table 2 Mapping relationship of PCF local pre-configuration (considering disaster recovery)

And sign a contract for a dedicated DNN or a full-network DNN on the unified data management device UDM at the location, and replace the DNN list.

The replacement DNN list includes multiple replacement DNNs, which are used to access the nearest enterprise data center (i.e., the client-side server/data center in the roaming area) when the terminal is roaming. Therefore, it is necessary to sign a contract in advance to ensure that the client-side server/data center in the corresponding area can be accessed nearby in the future.

In some embodiments, the specific DNN subscribed by the terminal includes a dedicated DNN or a full-network DNN, and a replacement DNN list.

It should be noted that a dedicated DNN refers to a dedicated DNN of a client-side server or a client-side data center, for example, a DNN with a regional suffix, DNN.gd.

The specific implementation process of step 200 is as follows:

The enterprise user terminal sends a registration request to the AMF through the gNB.

After AMF completes the UE authentication request, it discovers the enterprise user terminal's home UDM through the Subscription Permanent Identifier (SUPI) service, obtains the user's contract information from the enterprise user terminal UE's home UDM, and the home UDM returns the user's contract information to AMF.

Optionally, if AMF is to automatically identify a specific DNN, it is necessary to trigger the establishment of the N15 interface. Therefore, the specific DNN signed by the terminal may also carry a special identification field that triggers the establishment of the N15 interface.

Step 201: The AMF determines that the conditions for establishing an N15 connection are met based on the specific DNN signed by the terminal, and the AMF establishes an N15 connection;

The conditions for establishing an N15 connection are that the specific DNN is included in the whitelist pre-configured locally by the AMF, or that the specific DNN contains a special identification field that triggers the establishment of the N15 interface.

Based on the specific DNN to which the terminal has signed a contract, the AMF determines that the conditions for establishing an N15 connection are met, and then establishes an N15 connection for the specific DNN.

Step 202: The AMF determines that the terminal is roaming, initiates two PCF service discovery processes to the NRF, and obtains information about the Visited Policy Control Function (V-PCF) and the Home Policy Control Function (H-PCF);

If the AMF determines that the terminal is roaming between provinces or internationally, the AMF initiates two PCF service discovery processes to the NRF for the terminal to obtain information about the visited policy control function V-PCF and the home policy control function H-PCF.

If AMF determines that the terminal has not roamed, AMF will initiate a PCF service discovery process to NRF for the terminal, that is, for users in the same province, only the V/H-PCF in the same province can be addressed and discovered.

Optionally, before determining that the terminal roams, the method further includes:

The AMF determines whether the terminal is roaming between provinces based on the information of the terminal's home data management device UDM.

In order to reduce system overhead, AMF can determine whether the UE is roaming between provinces based on the UDM source. For example, if the province field in the FQDN of UDM is outside the province, it is roaming, and then determine whether to perform PCF service discovery twice.

Furthermore, AMF initiates two policy control function PCF service discovery processes to NRF to obtain information about the visited policy control function V-PCF and the home policy control function H-PCF, including:

Discover the V-PCF through a service scope (ServingScope, SSP) or a service name (service-names), and obtain information of the V-PCF;

The H-PCF is discovered through a Generic Public Subscription Identifier (GPSI) or a subscription permanent identifier SUPI, and information about the H-PCF is obtained.

Step 203: The AMF sends a mobility and access management (Access and Mobility, AM) policy control establishment message to the H-PCF through the V-PCF;

It can be understood that V-PCF transfers messages between AMF and H-PCF. AMF and V-PCF communicate via N15 interface. V-PCF and H-PCF communicate via N24 interface.

Specifically, the AMF sends an AM policy control establishment message to the H-PCF through the V-PCF, including:

The AMF sends an AM policy control establishment message to the V-PCF, where the AM policy control establishment message is used to trigger the V-PCF to establish an N24 coupling with the H-PCF so that the V-PCF obtains the AM policy from the H-PCF.

In some embodiments, the AM policy control establishment message refers to an Npcf_AMPolicyControl_create message. The AMF sends the AM policy control establishment message to the V-PCF through the N15 interface. That is, the AM policy control establishment message here can be called the first N15 session request.

The V-PCF checks whether there is valid H-PCF information, then the V-PCF creates an N24 coupling and sends a first N24 session request to the H-PCF to request the H-PCF to establish terminal AM policy control, which can be understood as requesting the H-PCF for the AM policy for the terminal.

V-PCF receives the first N24 session request response sent by H-PCF, obtains the AM policy, and then V-PCF sends an AM policy control establishment response message to AMF. V-PCF sends an AM policy control establishment response message to AMF through the N15 interface. That is, the AM policy control establishment response message here can be called the first N15 session request response.

It should be noted that AMF sends an AM policy control establishment message to the H-PCF through the V-PCF, including AMF sending a first N15 session request to V-PCF, and V-PCF sending a first N24 session request to H-PCF, that is, the first N15 session request and the first N24 session request are specific forms of AM policy control establishment messages flowing in different network elements.

Step 204, the AMF receives an AM policy control establishment response message, the AM policy control establishment response message carries SMF selection indication information, and the SMF selection indication information is used to indicate that the AMF needs to initiate a DNN replacement process when it detects that the terminal has established a new protocol data unit (PDU) session based on a specific DNN subscribed by the terminal;

Specifically, the H-PCF sends a first N24 session request response to the V-PCF, and the V-PCF sends an AM policy control establishment response message to the AMF, which is the first N15 session request response.

The first N24 session request response and the first N15 session request response are specific forms of the AM policy control establishment response message flowing in different network elements.

The AMF receives the first N15 session request response sent by the V-PCF, and the first N15 session request response includes: the trigger rule of SMF selection change (SMF_SELECT_CH) and the SMF selection indication identifier (smfSelInfo information element), and the trigger rule of SMF selection change and the SMF selection indication identifier are used to indicate that when the AMF detects that the terminal has created a new PDU session based on the specific DNN signed by the terminal, it needs to initiate a DNN replacement process to the PCF.

That is, AMF obtains the AM policy from H-PCF through V-PCF and establishes AM policy control. That is, when the terminal creates a new PDU session based on the specific DNN signed by the terminal, it needs to initiate a DNN replacement process to PCF.

After completing the above steps, AMF returns a registration success message to the user terminal.

Step 205: The AMF receives a PDU session establishment message sent by the terminal, where the PDU session establishment message carries a first DNN, where the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

After the terminal registration is completed, the terminal sends a PDU session establishment request to the visited AMF, and the PDU session establishment request carries the DNN requested by the terminal.

Step 206: The AMF determines that the first DNN is in the specific DNN, and sends an AM policy control update message to the H-PCF through the V-PCF;

The AMF confirms that the first DNN needs to initiate a DNN replacement process based on the specific DNN obtained in the registration process of the terminal, that is, the first DNN belongs to the DNN signed by the terminal, then the AMF determines that a DNN replacement process needs to be initiated.

The AMF then sends an AM policy control update message to the V-PCF, where the AM policy control update message is used to trigger the V-PCF to establish an N24 coupling with the H-PCF so that the V-PCF obtains a replacement DNN from the H-PCF.

In some embodiments, the AM policy control update message refers to an Npcf_AMPolicyControl_Update message, and the AMF sends the AM policy control update message to the V-PCF through the N15 interface, that is, the AM policy control update message here is a second N15 session request.

The AM policy control update message carries information of the first DNN and the H-PCF. Optionally, the AM policy control update message carries an smfSelInfo information element and the H-PCF information, and the smfSelInfo information element includes the first DNN.

The V-PCF checks that there is valid H-PCF information for the session (i.e., the second N15 session request) and that DNN replacement is required this time, and then sends a second N24 session request to the H-PCF, where the second N24 session request carries information related to the first DNN and terminal location.

Optionally, the second N24 session request carries user information, GUMAI, and smfSelInfo information element, where the smfSelInfo information element includes the first DNN, that is, the dedicated DNN or the full-network DNN requested by the terminal.

The H-PCF matches the replacement DNN used by the terminal to access the client-side server/data center nearby in the roaming area according to the terminal location-related information and the mapping relationship between each service area and the replacement DNN preconfigured by the H-PCF for each nearby access service package;

Optionally, the terminal location related information includes: a visited area information of the terminal, information of an operator accessed by the terminal, or location information of the terminal.

The H-PCF sends a second N24 session request response to the V-PCF, where the second N24 session request response carries the replacement DNN.

In a specific implementation, the H-PCF sends a second N24 session request response to the V-PCF, where the second N24 session request response carries an smfSelInfo information element, and the smfSelInfo information element includes the replacement DNN determined by the H-PCF.

If remote disaster recovery is considered, H-PCF will feed back the information of primary and backup DNN replacement to V-PCF.

The V-PCF decides on a DNN, i.e., a second DNN, for the terminal to access the nearest client-side server/data center based on other local strategies and the replacement DNN determined by the H-PCF.

It should be noted that other local policies of V-PCF refer to policy rules corresponding to other local business processes of V-PCF.

Step 207: The AMF receives an AM policy control update response message, where the AM policy control update response message carries the second DNN.

The V-PCF sends an AM policy control update response message to the AMF, and the AM policy control update response message carries the second DNN. The V-PCF sends an AM policy control update response message to the AMF through the N15 interface, that is, the AM policy control update response message here can also be called a second N15 session request response.

In some embodiments, the AM policy control update response message is a Npcf_AMPolicyControl_UpdateResponse message.

Optionally, the AM policy control update response message carries a second smfSelInfo information element, and the second smfSelInfo information element includes a second DNN. If remote disaster recovery is considered, the second DNN includes: a primary DNN and a backup DNN.

Step 208: The AMF determines the target SMF based on the second DNN, and enables the terminal to access the client-side data center nearby through the target SMF.

Specifically, after the AMF service discovers the nearest service SMF, it sends the Nsmf_PDUSession_CreateSMContext Request message to the nearest service SMF (or through I-SMF) to request the establishment of a PDN connection. If remote disaster recovery is considered, after the AMF discovers the failure of the primary node, it discovers the backup node SMF. After the nearest service SMF obtains the user contract data from the home location, it sends the Nsmf_PDUSession_CreateSMContext Response message to the AMF (or through I-SMF).

The nearest service SMF discovers the user's affiliated H-PCF based on the number segment service, and obtains the user policy subscription data from the user's affiliated H-PCF.

The nearest service SMF selects the nearest service UPF through local configuration and establishes a PDU connection through the N4 Session EstablishmentRequest/Response message.

The nearest service SMF (or replies Nsmf_PDUSession_Create Response to I-SMF) sends a Namf_Communication_N1N2MessageTransfer message to AMF.

The AMF returns a PDU session establishment response to the user terminal.

The user terminal accesses the nearest client-side server/data center through the nearest UPF.

In an embodiment of the present application, by pre-configuring a dedicated DNN replacement strategy in the home PCF, that is, the mapping relationship between the service area and the replacement DNN, in the terminal registration process, when the AMF determines that the terminal is in a roaming state, it initiates two PCF service discovery processes to obtain information about the V-PCF and H-PCF, and then obtains the AM policy from the H-PCF through the V-PCF. When the AMF receives a new PDU session based on a specific DNN by the terminal, it initiates a DNN replacement process to the H-PCF through the V-PCF to obtain the DNN information finally determined by the V-PCF. The AMF uses the DNN information to discover the SMF of the nearest access node, thereby enabling users to access the nearest client-side server or data center. There is no need to configure complex TAC data to support flexible selection of the nearest data center access on the enterprise side based on the user's visit location. When new enterprise needs and changes in the deployment location of the enterprise-side data center are added, there is no need for complex full-network bureau data configuration. When the location of the industry customer data center or the nearest access province changes, the access policy adjustment can be achieved by simply modifying the user's home PCF configuration data. In terms of networking, there are no restrictions such as the need for secondary networking of NRF, and the networking method is more flexible. The network configuration and maintenance data is small, and the user terminal side only configures the dedicated DNN information signed by the enterprise. There is no need to change the DNN information as the customer-side data center area planning changes. This application has no special requirements for the user terminal UE and the enterprise data center side, supports flexible and rapid deployment, and can meet the user's automatic access needs when the customer data center changes, and is highly practical.

In some embodiments, the specific DNN subscribed by the terminal also carries a special identification field that triggers the establishment of the N15 interface;

The AMF determines, based on the specific DNN subscribed by the terminal, that a condition for establishing an N15 connection is satisfied, and the AMF establishes the N15 connection, including:

If the AMF detects that the specific DNN subscribed by the terminal is included in the whitelist pre-configured locally by the AMF, or the AMF detects that the specific DNN subscribed by the terminal contains the special identification field that triggers the establishment of the N15 interface, the AMF determines that the conditions for establishing the N15 connection are met;

The AMF establishes an N15 connection and deletes the special identification field in the specific DNN signed by the terminal.

That is, in one implementation, the AMF detects that the specific DNN subscribed by the terminal is included in the AMF locally pre-configured whitelist, and then establishes an N15 connection.

In another implementation, the AMF detects that the specific DNN to which the terminal has signed a contract contains the special identification field that triggers the establishment of the N15 interface, then establishes an N15 connection, and after the N15 connection is successfully established, deletes the special identification field in the specific DNN to which the terminal has signed a contract.

In the embodiment of the present application, based on the N15 interface, the SMF selection management function of the AM POLICY is used to enable users to access the nearest client-side server or data center.

In some embodiments, the replacement DNN determined by the H-PCF includes: replacing the active DNN and replacing the standby DNN.

In the mapping relationship between the service area pre-configured by H-PCF and the replacement DNN, the replacement DNN includes replacing the active DNN and replacing the standby DNN, thus realizing remote disaster recovery in the nearby access scenario.

In some embodiments, in consideration of disaster recovery, the second DNN includes: a primary DNN and a backup DNN;

The AMF determines the target SMF based on the second DNN, and enables the terminal to access the client-side data center nearby through the target SMF, including:

The AMF determines the main SMF based on the main DNN, and enables the terminal to access the client-side data center nearby through the main SMF;

After the main SMF fails, a backup SMF is determined based on the backup DNN, and the terminal is connected to the nearest customer-side data center through the backup SMF.

By taking disaster recovery into consideration, the embodiment of the present application enables the terminal to access the client-side data center through the backup SMF corresponding to the backup DNN when a failure occurs in the main SMF corresponding to the main DNN, thereby realizing remote disaster recovery in the nearby access scenario and improving the reliability of nearby access.

In some embodiments, the method further comprises:

If it is determined that the terminal is not roaming, a PCF service discovery process is initiated to the visited NRF to obtain the local PCF information.

Optionally, if the AMF determines that the UE has not roamed between provinces based on the UDM source, for example, if the province field in the FQDN based on the UDM is determined to be the same province, then roaming has not occurred. In this case, it is determined that only one PCF service discovery is required, thereby saving system overhead.

In some embodiments, the target SMF carries the second DNN when registering with the network storage function NRF.

In some embodiments, the method further comprises:

The AMF obtains a new replacement DNN from the H-PCF based on a local configuration policy change or a V-PCF change;

In the case where the new replacement DNN is identical to the second DNN, inserting an I-SMF as needed;

In case the new replacement DNN is different from the second DNN, PDU session reconstruction is initiated.

When the user roams, AMF will re-initiate the N15 session based on the local configuration policy or V-PCF changes, and obtain the new replacement DNN information from PCF. When the replacement DNN sent is the same as the original DNN information, the nearest access point SMF will not be reselected, and the I-SMF will only be inserted as needed; if it is found that the newly sent replacement DNN is different from the original replacement DNN, the session establishment process needs to be re-initiated.

Optionally, session reconstruction may implement different triggering logics according to the session state, such as not reconstructing the session in a connected state and only reconstructing the session in an idle state, so as to improve user perception.

The access method provided in the present application can achieve: 1) when a user roams, the user can access the server/data center of the customer area center according to the customer-side area corresponding to the roaming location; 2) when the customer-side regional planning or access location changes, there are no new requirements for the terminal, and the terminal side does not need to modify the terminal-side DNN information to achieve the nearest access to the customer data center; 3) when the location of the industry customer data center or the nearest access province changes, the access policy can be adjusted by simply modifying the user-attributed PCF configuration data.

FIG3 is a second flow chart of the access method provided in the embodiment of the present application. As shown in FIG3, the access method uses the visited location policy control function V-PCF as the execution subject. It should be noted that in order to clearly describe the access method provided in the embodiment of the present application, V-PCF is used as the execution subject for description, and the access method provided in the embodiment of the present application can also be applied to other network elements that can execute the steps of the access method, and the present application does not limit this.

The access method comprises the following steps:

Step 300: The visited location policy control function V-PCF receives an AM policy control update message sent by the AMF, where the AM policy control update message carries information of the first DNN and the H-PCF, where the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

Optionally, the V-PCF receives an access and mobility AM policy control update message sent by an access and mobility management function AMF of a visited location. The access management policy control update message carries an smfSelInfo element and information of the H-PCF. The smfSelInfo element includes a first DNN, which is a dedicated DNN or a network-wide DNN requested by the terminal.

Step 301: The V-PCF checks that the information of the H-PCF is valid, and sends a second N24 session request to the H-PCF, where the second N24 session request carries the first DNN and information related to the terminal location;

The terminal location related information includes the visited area information of the terminal, the operator information accessed by the terminal or the location information of the terminal.

Optionally, the V-PCF checks whether there is valid H-PCF information and DNN replacement is required this time, then the V-PCF sends an N24 session request to the H-PCF, and the N24 session request carries the terminal information, GUAMI, and the smfSelInfo element.

Step 302: The V-PCF receives a second N24 session request response sent by the H-PCF, where the second N24 session request response carries a replacement DNN determined by the H-PCF.

The V-PCF receives the N24 session request response sent by the H-PCF, where the N24 session request response carries an smfSelInfo information element, and at this time, the smfSelInfo information element includes a replacement DNN determined by the H-PCF for the terminal to access nearby;

Step 303: The V-PCF determines a second DNN according to other local strategies and the replacement DNN determined by the H-PCF;

The V-PCF decides on a DNN, i.e., a second DNN, for the terminal to access the nearest client-side server/data center based on other local strategies and the replacement DNN determined by the H-PCF.

It should be noted that other local policies of V-PCF refer to policy rules corresponding to other local business processes of V-PCF.

Step 304: The V-PCF sends an AM policy control update response message to the AMF, where the AM policy control update response message carries the second DNN.

The V-PCF sends an AM policy control update response message to the AMF, and the AM policy control update response message carries the second DNN. The V-PCF sends an AM policy control update response message to the AMF through the N15 interface, that is, the AM policy control update response message here can also be called a second N15 session request response.

In some embodiments, the AM policy control update response message is a Npcf_AMPolicyControl_UpdateResponse message.

Optionally, the AM policy control update response message carries a second smfSelInfo information element, and the second smfSelInfo information element includes a second DNN. If remote disaster recovery is considered, the second DNN includes: a primary DNN and a backup DNN.

The second DNN is used by the AMF to determine the target SMF, so as to enable the terminal to access the client-side data center nearby through the target SMF;

The terminal has previously signed a nearby access service package at the H-PCF, and the H-PCF pre-configures a mapping relationship between each service area and a replacement DNN for each nearby access service package;

The replacement DNN determined by the H-PCF is determined based on the terminal location related information and the mapping relationship.

In some embodiments, the replacing the DNN includes: replacing the active DNN and replacing the standby DNN.

In some embodiments, the method further comprises:

The V-PCF receives an AM policy control establishment message sent by the AMF;

The V-PCF detects that there is valid H-PCF information, creates an N24 coupling, and sends a first N24 session request to the H-PCF, where the first N24 session request is used to request the H-PCF to establish terminal AM policy control;

The V-PCF receives the first N24 session request response sent by the H-PCF, and sends an AM policy control establishment response message to the AMF. The AM policy control establishment response message carries the triggering rule for SMF selection change and the SMF selection indication identifier. The triggering rule for SMF selection change and the SMF selection indication identifier are used to indicate that when the AMF matches the terminal to create a new PDU session based on the specific DNN signed by the terminal, it is necessary to initiate a DNN replacement process to the PCF.

Optionally, the AM policy control establishment message refers to an Npcf_AMPolicyControl_create message. The AMF sends the AM policy control establishment message to the V-PCF through the N15 interface. That is, the AM policy control establishment message here can be called the first N15 session request.

The V-PCF receives the AM policy control establishment message sent by the AMF, checks whether there is valid H-PCF information, and then creates an N24 coupling and sends a first N24 session request to the H-PCF to request the H-PCF to establish terminal AM policy control, which can be understood as requesting the H-PCF for the AM policy for the terminal.

V-PCF receives the first N24 session request response sent by H-PCF, obtains the AM policy, and then V-PCF sends an AM policy control establishment response message to AMF. V-PCF sends an AM policy control establishment response message to AMF through the N15 interface. That is, the AM policy control establishment response message here can be called the first N15 session request response.

The AM policy control establishes a response message carrying the trigger rule (SMF_SELECT_CH) for SMF selection change and the SMF selection indication identifier (smfSelInfo element). The trigger rule for SMF selection change and the SMF selection indication identifier are used to indicate that when the AMF matches the terminal to create a new PDU session based on the specific DNN signed by the terminal, it is necessary to initiate a DNN replacement process to the PCF.

In an embodiment of the present application, by pre-configuring a dedicated DNN replacement policy in the home PCF, that is, the mapping relationship between the service area and the replacement DNN, in the terminal registration process, when the AMF determines that the terminal is in a roaming state, it initiates two PCF service discovery processes to obtain information about the V-PCF and H-PCF, and then obtains the AM policy from the H-PCF through the V-PCF. The present application proposes to transmit the AM POLICY through the N24 interface. When the AMF receives a new PDU session based on a specific DNN by the terminal, the DNN replacement process is initiated to the H-PCF through the V-PCF to obtain the DNN information finally determined by the V-PCF. The AMF uses the DNN information to discover the SMF of the nearest access node, thereby enabling the user to access the nearest client-side server or data center. It does not require the configuration of complex TAC data to support flexible selection of the nearest data center access on the enterprise side based on the user's visiting location. When new enterprise needs and changes in the deployment location of the enterprise-side data center are added, there is no need for complex network-wide bureau data configuration. When the location of the industry customer data center or the nearest access province changes, the access policy adjustment can be achieved by simply modifying the user's home PCF configuration data. In terms of networking, it does not involve restrictions such as NRF requiring secondary networking, and the networking method is more flexible. The network configuration and maintenance data are small, and the user terminal side only configures the dedicated DNN information signed by the enterprise, and does not need to change the DNN information with the changes in the regional planning of the customer-side data center. This application has no special requirements for the user terminal UE and the enterprise data center side, supports flexible and rapid deployment, and can meet the user's automatic access needs under the changes of the customer data center, and is highly practical.

FIG4 is a third flow chart of the access method provided in the embodiment of the present application. As shown in FIG4, the access method uses the home policy control function H-PCF as the execution subject. It should be noted that in order to clearly describe the access method provided in the embodiment of the present application, the H-PCF is used as the execution subject for description, and the access method provided in the embodiment of the present application can also be applied to other network elements that can execute the steps of the access method, and the present application does not limit this.

The access method comprises the following steps:

Step 400: The home policy control function H-PCF receives a second N24 session request sent by the V-PCF, where the second N24 session request carries information related to the first DNN and the terminal location; the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

Optionally, the H-PCF receives an N24 session request sent by the V-PCF, wherein the N24 session request carries terminal information, GUAMI, and an smfSelInfo element, wherein the smfSelInfo element includes a first DNN, and the first DNN is a dedicated DNN or a full-network DNN requested by the terminal.

Step 401: The H-PCF determines a replacement DNN for the terminal to access nearby according to the terminal location related information and a preconfigured mapping relationship;

The H-PCF matches the replacement DNN used by the terminal to access the client-side server/data center nearby in the roaming area according to the terminal location-related information and the mapping relationship between each service area and the replacement DNN preconfigured by the H-PCF for each nearby access service package;

Optionally, the terminal location related information includes: a visited area information of the terminal, information of an operator accessed by the terminal, or location information of the terminal.

Step 402: The H-PCF sends a second N24 session request response to the V-PCF, where the second N24 session request response carries the replacement DNN determined by the H-PCF.

The H-PCF sends a second N24 session request response to the V-PCF, where the second N24 session request response carries the replacement DNN.

In a specific implementation, the H-PCF sends a second N24 session request response to the V-PCF, where the second N24 session request response carries an smfSelInfo information element, and the smfSelInfo information element includes the replacement DNN determined by the H-PCF.

If remote disaster recovery is considered, H-PCF will feed back the information of primary and backup DNN replacement to V-PCF.

Among them, the terminal has previously signed a nearby access service package in the H-PCF; the H-PCF preconfigures the mapping relationship for each nearby access service package, and the mapping relationship is a mapping relationship between each service area and the replacement DNN.

In some embodiments, the replacing the DNN includes: replacing the active DNN and replacing the standby DNN.

In some embodiments, the method further comprises:

The H-PCF receives a first N24 session request sent by the V-PCF, where the first N24 session request is used to request the H-PCF to establish a terminal AM policy control;

The H-PCF sends a first N24 session request response to the V-PCF, and the first N24 session request response includes: a trigger rule for SMF selection change and an SMF selection indication identifier, and the trigger rule for SMF selection change and the SMF selection indication identifier are used to indicate that when a new PDU session is created based on a specific DNN signed by the terminal and matched to the terminal, a DNN replacement process needs to be initiated to the PCF.

In an embodiment of the present application, by pre-configuring a dedicated DNN replacement policy in the home PCF, that is, the mapping relationship between the service area and the replacement DNN, in the terminal registration process, when the AMF determines that the terminal is in a roaming state, it initiates two PCF service discovery processes to obtain information about the V-PCF and H-PCF, and then obtains the AM policy from the H-PCF through the V-PCF. The present application proposes to transmit the AM POLICY through the N24 interface. When the AMF receives a new PDU session based on a specific DNN by the terminal, the DNN replacement process is initiated to the H-PCF through the V-PCF to obtain the DNN information finally determined by the V-PCF. The AMF uses the DNN information to discover the SMF of the nearest access node, thereby enabling the user to access the nearest client-side server or data center. It does not require the configuration of complex TAC data to support flexible selection of the nearest data center access on the enterprise side based on the user's visiting location. When new enterprise needs and changes in the deployment location of the enterprise-side data center are added, there is no need for complex network-wide bureau data configuration. When the location of the industry customer data center or the nearest access province changes, the access policy adjustment can be achieved by simply modifying the user's home PCF configuration data. In terms of networking, it does not involve restrictions such as NRF requiring secondary networking, and the networking method is more flexible. The network configuration and maintenance data are small, and the user terminal side only configures the dedicated DNN information signed by the enterprise, and does not need to change the DNN information with the changes in the regional planning of the customer-side data center. This application has no special requirements for the user terminal UE and the enterprise data center side, supports flexible and rapid deployment, and can meet the user's automatic access needs under the changes of the customer data center, and is highly practical.

Figure 5 is a schematic diagram of a solution provided by an embodiment of the present application for a terminal that has signed a contract for a dedicated DNN or a full-network DNN to access the nearest client-side data center.

FIG6 is a schematic diagram of signaling interaction in the terminal registration phase in the access method provided in an embodiment of the present application. As shown in FIG6 , the main process of the terminal registration phase includes:

① The enterprise user terminal sends a registration request to the AMF through the 5G wireless network gNB.

② After AMF completes the UE authentication request, it discovers the UDM of the enterprise user terminal through the SUPI service, obtains the user's contract information from the UDM of the enterprise user terminal UE, and the UDM of the home location returns the user contract data (including the user's contract DNN information) to AMF.

③AMF detects that the DNN returned by the UDM of the home region is included in the locally pre-configured whitelist, or the DNN information contains a specific identification field that triggers the establishment of N15, triggering the establishment of N15, and at the same time determines that the user is a roaming user (for example, if the province field in the FQDN of the UDM is used to determine that it is not in the province, then it is roaming). Then AMF needs to initiate two PCF service discovery processes to the roaming NRF: the first time through the ServingScope service to discover the roaming V-PCF, the second time through the GPSI service to discover the home H-PCF, and establish a coupling connection with the roaming V-PCF through the N15 interface. If the user is not roaming, only one service discovery of the local V/H-PCF can be initiated.

④AMF executes the access and mobility policy control establishment process and establishes the N15 interface to the roaming V-PCF.

⑤ V-PCF checks that the N15 session established by AMF has valid H-PCF information, then creates N24 coupling to request the terminal AM policy from H-PCF.

⑥V-PCF initiates N24 session request and requests AM policy from H-PCF.

⑦AMF obtains the terminal AM policy establishment request response from the H-PCF through the V-PCF. The session request response message carries SMF_SELECT_CH and smfSelInfo to indicate that when AMF creates a new PDU session based on the specific DNN signed by the terminal, it needs to initiate a DNN replacement process to PCF.

The other processes are the same as the standard process. AMF returns a registration success message to the user terminal.

FIG7 is a schematic diagram of signaling interaction during the session establishment phase in the access method provided in an embodiment of the present application. As shown in FIG7 , the main process of the session establishment phase includes:

① After the user terminal successfully registers, it sends a request to AMF to establish a PDU session.

②AMF confirms that the specific DNN carried by the terminal needs to initiate a DNN replacement process based on the specific DNN list obtained in the terminal registration process.

③AMF sends the Npcf_AMPolicyControl_Update message to the roaming V-PCF, carrying the smfSelInfo element, which contains the dedicated or network-wide DNN information requested from the user terminal.

④ The visited V-PCF checks that there is valid H-PCF information for the session and that DNN replacement is required this time. The V-PCF establishes an N24 coupling connection to the home H-PCF.

⑤ The visited V-PCF establishes N24 to the home H-PCF, which carries user information, GUAMI, and smfSelInfo (DNN is the dedicated or network-wide DNN information requested by the user terminal).

⑥ The home H-PCF matches the replacement DNN information used by the user terminal in the nearest data center in the roaming area according to the GUAMI.

⑦ The home H-PCF sends a response message to the roaming V-PCF with the smfSelInfo element, which contains the replacement DNN of the nearest data center in the roaming area. If off-site disaster recovery is required, the H-PCF will feed back the information of the primary and standby replacement DNNs to the V-PCF.

⑧ The visiting location V-PCF combines other local strategies and the DNN information returned by the home location H-PCF to decide the DNN that the user will eventually use.

⑨ The visited V-PCF sends the Npcf_AMPolicyControl_Update Response message to the AMF, carrying the smfSelInfo information element, which contains the replacement DNN of the nearest data center in the roaming area. If remote disaster recovery is considered, it also contains the information of the primary and backup replacement DNNs.

⑩a～b: After discovering the nearest service SMF, the AMF service sends the Nsmf_PDUSession_CreateSMContext Request message to the nearest service SMF (or through I-SMF) to request the establishment of a PDN connection. If remote disaster recovery is considered, after discovering the failure of the primary node, the AMF discovers the backup node SMF. After the nearest service SMF obtains the user subscription data from the home location, it sends the Nsmf_PDUSession_CreateSMContext Response message to the AMF (or through I-SMF).

The nearest service SMF discovers the user's affiliated H-PCF based on the number segment service, and obtains the user policy subscription data from the user's affiliated H-PCF.

The nearest service SMF selects the nearest service UPF through local configuration and establishes a PDU connection through the N4Session EstablishmentRequest/Response message.

The nearest service SMF (or replies Nsmf_PDUSession_Create Response to I-SMF) sends a Namf_Communication_N1N2MessageTransfer message to AMF.

The AMF returns a PDU session establishment response to the user terminal.

The user terminal accesses the nearest enterprise data center through the nearest UPF.

Figure 8 is a schematic diagram of the signaling interaction of the switching process in the access method provided by the embodiment of the present application. When the user is roaming, the AMF will re-initiate the N15 session based on the local configuration policy or V-PCF changes, and obtain new replacement DNN information from the PCF. When the replacement DNN issued is the same as the original DNN information, the nearest access point SMF will no longer be reselected, and the I-SMF will only be inserted as needed; if it is found that the newly issued replacement DNN is different from the original replacement DNN, the session establishment process must be re-initiated. Session reconstruction can implement different trigger logics according to the session state, such as no session reconstruction in the connected state, and only rebuilding the session in the idle state to enhance user perception.

In order to solve the technical problems of the present application, the present application also provides another solution - a solution for realizing terminal nearby access in a multi-DNN scenario with seamless diversion.

This scenario is a solution based on the seamless multi-DNN solution scenario proposed by a certain operator. This basic solution is a solution for the business requirement of "unconscious switching and coexistence of user public network services and private network services". It is mainly used when users want to use public network services, and still use the general DNN to implement public network service access; when users need to use private network services (access the corporate intranet), the network establishes an IP channel for the user UE to clear the private network services based on the seamless multi-DNN solution. During this process: (1) The user does not need to perform additional operations on the terminal UE (except clicking on the link/entering the target URL/URI/IP address). (2) The user terminal UE has no perception, such as the need to start a new DNN. (3) Supports user roaming in different locations.

FIG9 is a fourth flow chart of the access method provided in the embodiment of the present application. The method is executed by SMF. It should be noted that in order to clearly describe the access method provided in the embodiment of the present application, the SMF is used as the execution subject for description. The access method provided in the embodiment of the present application can also be applied to other network elements that can execute the steps of the access method, and the present application does not limit this. As shown in FIG9, the access method includes:

Step 900: The session management function SMF receives a specific DNN determined by the home PCF/UDR according to the access location of the terminal and a preconfigured mapping relationship;

Step 901: The SMF executes a PCC (Policy and Charging Control) policy based on the specific DNN, and activates a PDU session corresponding to the specific DNN for the terminal upon receiving a first event reported by the UPF;

The first event is used to indicate that the destination address in the data message of the general DNN service of the terminal is the address corresponding to the specific DNN;

The terminal has previously signed a contract to activate a PCC policy on the PCF/UDR to which the terminal belongs, and the PCC policy is used to indicate that when a destination address corresponding to a specific DNN is detected in a data message of a general DNN service of the terminal, the specific DNN is activated for the terminal;

The home PCF/UDR preconfigures a mapping relationship between each service area and a specific DNN.

In some embodiments, the method further comprises:

The SMF performs unified data management UDM service discovery on the network storage function NRF, and obtains the session management subscription data of the terminal from the terminal's home UDM/UDR;

The SMF performs PCF service discovery on the NRF, and obtains the PCC policy subscribed by the terminal from the home PCF/UDR of the terminal.

In some embodiments, activating a PDU session of a dedicated DNN or a full-network DNN for a terminal includes:

The SMF performs target SMF service discovery of a dedicated DNN or a full-network DNN to the NRF;

The SMF uses itself as the dedicated DNN of the terminal or the I-SMF of the whole network DNN, and selects UPF as the dedicated DNN of the terminal or the I-UPF of the whole network DNN.

In some embodiments, the SMF is selected by the AMF for the universal DNN service of the terminal upon receiving a universal DNN activation request sent by the terminal.

In some embodiments, the specific DNN includes: a dedicated DNN or a full-network type DNN.

In some embodiments, the method further comprises:

When the roaming location of the terminal changes, the SMF receives the updated specific DNN determined by the PCF according to the latest access location of the terminal and the preconfigured mapping relationship;

The SMF executes the updated PCC policy based on the updated specific DNN, and re-establishes the PDU session corresponding to the updated specific DNN for the terminal when receiving the second event reported by the UPF;

The second event is used to indicate that the destination address in the data message of the general DNN service of the terminal is the address corresponding to the updated specific DNN;

Among them, the PCF identifies the latest access location of the terminal through the AMF GUAMI information obtained through the N7 interface, and based on the pre-configured mapping relationship, re-sends new private network or full network DNN information to the intelligent diversion SMF according to the latest access location of the terminal.

In some embodiments, re-establishing a PDU session corresponding to the updated specific DNN for the terminal includes:

According to the triggering logic of the session state, the session is not reestablished when the terminal is in a connected state, and the PDU session is reestablished only when the terminal is in an idle state.

FIG10 is a schematic diagram of a solution for realizing terminal proximity access in a multi-DNN scenario with seamless traffic diversion provided in the present application.

First, you need to sign a contract ( step):

The PCC policy of "Private network service diversion strategy in public network service" is signed and activated in the user's PCF/UDR. The PCC policy indicates that if a URL/URI or IP address with the destination address of "private network" is detected in the user data message of the PDU session of the general DNN, the "private network DNN" will be activated for the user.

In the user-owned UDM/UDR, the user signs a contract for a general DNN and an enterprise private network DNN.

(2) Main implementation process:

① When a user uses data services (public network services or private network services), the user terminal UE initiates a general DNN activation request in the roaming area.

②AMF selects the target SMF for the general DNN service.

③ After the target SMF (SMF1 in Figure 10) performs UDM service discovery on the NRF, it obtains and subscribes to the user's SM (session management) subscription data from the user's home UDM/UDR. The relevant process follows the 3GPP standard.

④ The target SMF performs PCF service discovery on the NRF and obtains the PCC policy subscribed by the user from the user's PCF/UDR. Among them: the target SMF of the general DNN service (SMF1 in Figure 10) and the UPF selected by the target SMF (UPF1 in Figure 10) need to support the execution and processing of the PCC policy of the "Private network service diversion strategy in public network services" of this solution. That is: when the destination URL/URI or destination IP address in the user data message of the general DNN service of the user terminal UE is the destination URL/URI or destination IP address of the "enterprise intranet", a private network DNN session connection is established.

⑤General DNN session establishment.

⑥ When the conditions are met (i.e., the destination URL/URI or destination IP address in the user data message of the general DNN service of the user terminal UE is the destination URL/URI or destination IP address of the "enterprise intranet"), the target UPF reports the relevant events to the SMF.

⑦ The target SMF (SMF1 in Figure 10) executes the PCC policy, and upon receiving the relevant events reported by the UPF (UPF1 in Figure 10), activates the PDU session of the corresponding private network DNN for the user. Including: SMF performs SMF service discovery of the private network DNN to the NRF, and selects the SMF that establishes the private network DNN for the user terminal UE; SMF (SMF1 in Figure 10) uses itself as the I-SMF of the user's private network DNN, and selects UPF (UPF1 in Figure 10) as the I-UPF of the user's private network DNN.

⑧Private network DNN session is established.

Based on the above business scenarios and implementation mechanisms, in order to meet the needs of relevant users in this scenario to select the nearest access node based on the user's location when accessing the private network, this proposal proposes the following solution.

FIG11 is a fifth flow chart of the access method provided in the embodiment of the present application. As shown in FIG11 , the main implementation mechanism is as follows:

(1) User contract: The user belongs to the PCF/UDR and signs up for the PCC policy of "Private network service diversion strategy in public network service". The PCC policy specifies that if a URL/URI or IP address with the destination address of "private network" is detected in the user data message of the PDU session of the general DNN, the "private network DNN or global network-type DNN" will be activated for the user.

(2) The following configurations are added to the user attribution PCF: Support for configuring the mapping relationship between each access province and the private network or the whole network DNN. If you need to make a judgment based on more detailed location information (such as TA), you can also map it based on other user location information obtained.

Table 3 PCF policy configuration

Nearby access node Service Area Enterprise private network or full network DNN Beijing Beijing/Hebei/Shandong and other northern provinces Private network DNN.bj or a full network DNN1 Guangdong Guangdong/Guangxi/Yunnan and other southern provinces Private network DNN.gd or a full network class DNN2

(3) PCF supports selecting different private networks or full-network DNNs based on different user access provinces (such as identifying user access provinces through AMF GUAMI and other information obtained through the N7 interface).

(4) Other processes are the same as the seamless multi-DNN solution. The SMF (intelligent diversion SMF) selected to execute the general DNN service obtains and executes the user's PCC policy through the SM-PCC process. If the destination is the URL or IP address of the enterprise intranet, the "enterprise private network or full network type DNN" is activated for the user (the private network or full network type DNN issued by the PCF according to the user's location).

(5) For user roaming scenarios, when a user roams from area 1 to area 2 planned by the enterprise, the PCF needs to support changes based on the GUAMI information and re-send new private network or full network DNN information to the intelligent traffic diversion SMF based on the correspondence between the user access location and the private network or full network DNN.

(6) Intelligent traffic diversion SMF needs to support re-establishing sessions based on new PCC policies (i.e., new private network or network-wide DNN information). This function can further support triggering logic based on session status, such as not reestablishing sessions in connected state, and only reestablishing sessions in idle state, so that users can access the nearest access node of the enterprise when moving across regions.

The access method provided in the embodiment of the present application realizes the nearest access to private network services based on the scenario of seamless switching and coexistence of user public network services and private network services, that is, the scenario where the user only signs a general DNN contract. The PCF re-issues the N7 PCC policy implementation mechanism based on the user access AMF GUAMI change information. The SMF updates the policy based on the PCC and provides a mechanism for rebuilding the session when the private network or the whole network DNN information changes. It flexibly selects the nearest data center access on the enterprise side based on the user's visiting location, meets customer needs, and is highly practical.

The access method provided in the embodiment of the present application may be executed by an access device. In the embodiment of the present application, the access device provided in the embodiment of the present application is described by taking the access method executed by the access device as an example.

FIG. 12 is one of the structural schematic diagrams of an access device provided in an embodiment of the present application. As shown in FIG. 12 , the access device 1200 includes:

The contract information acquisition unit 1210 is used to receive a registration request sent by a terminal and acquire contract information of the terminal, wherein the contract information includes: a specific data network name DNN contracted by the terminal;

The N15 establishing unit 1220 is used to determine, based on the specific DNN subscribed by the terminal, that a condition for establishing an N15 connection is met, and establish an N15 connection;

The first PCF service discovery unit 1230 is used to determine that the terminal is roaming, initiate two policy control function PCF service discovery processes to the NRF, and obtain information about the visited policy control function V-PCF and information about the home policy control function H-PCF;

A first AM policy control establishing unit 1240, configured to send an AM policy control establishment message to the H-PCF through the V-PCF;

An AM policy control establishment response unit 1250 is configured to receive an AM policy control establishment response message, wherein the AM policy control establishment response message carries SMF selection indication information, and the SMF selection indication information is used to indicate that the AMF needs to initiate a DNN replacement process when detecting that the terminal has established a new PDU session based on a specific DNN subscribed by the terminal;

The session establishing unit 1260 is configured to receive a PDU session establishing message sent by the terminal, wherein the PDU session establishing message carries a first DNN, and the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

An AM policy updating unit 1270 is configured to determine that the first DNN is in the specific DNN, and then send an AM policy control update message to the H-PCF through the V-PCF;

An AM policy update response unit 1280 is configured to receive an AM policy control update response message, wherein the AM policy control update response message carries a second DNN;

The SMF determining unit 1290 is configured to determine a target SMF based on the second DNN, and enable the terminal to access the client-side data center nearby through the target SMF;

The second DNN is determined by the V-PCF according to other local strategies and the replacement DNN determined by the H-PCF;

The terminal has previously signed a nearby access service package at the H-PCF, and the H-PCF pre-configures a mapping relationship between each service area and a replacement DNN for each nearby access service package;

The replacement DNN determined by the H-PCF is determined based on the visited area information of the terminal, the operator information accessed by the terminal or the location information of the terminal, and the mapping relationship.

Optionally, the specific DNN subscribed by the terminal also carries a special identification field that triggers the establishment of the N15 interface;

The AMF determines, based on the specific DNN subscribed by the terminal, that a condition for establishing an N15 connection is satisfied, and the AMF establishes the N15 connection, including:

If the AMF detects that the specific DNN subscribed by the terminal is included in the whitelist pre-configured locally by the AMF, or the AMF detects that the specific DNN subscribed by the terminal contains the special identification field that triggers the establishment of the N15 interface, the AMF determines that the conditions for establishing the N15 connection are met;

The AMF establishes an N15 connection and deletes the special identification field in the specific DNN signed by the terminal.

Optionally, the specific DNN subscribed by the terminal includes a dedicated DNN or a full-network DNN, and a replacement DNN list.

Optionally, in consideration of disaster recovery, the replacement DNN determined by the H-PCF includes: replacing the active DNN and replacing the standby DNN.

Optionally, in consideration of disaster recovery, the second DNN includes: a primary DNN and a backup DNN;

The AMF determines the target SMF based on the second DNN, and enables the terminal to access the client-side data center nearby through the target SMF, including:

The AMF determines the main SMF based on the main DNN, and enables the terminal to access the client-side data center nearby through the main SMF;

After the main SMF fails, a backup SMF is determined based on the backup DNN, and the terminal is connected to the nearest customer-side data center through the backup SMF.

Optionally, the access device further includes:

The roaming judgment unit is used to judge whether the terminal roams between provinces according to the information of the home data management device UDM of the terminal.

Optionally, the access device further includes:

The second PCF service discovery unit is used to initiate a PCF service discovery process to the visited NRF to obtain the local PCF information if it is determined that the terminal is not roaming.

Optionally, the initiating two policy control function PCF service discovery processes to the NRF to obtain information of the visited policy control function V-PCF and information of the home policy control function H-PCF includes:

Discover the V-PCF through the service scope SSP or service name, and obtain the information of the V-PCF;

The H-PCF is discovered through a general public subscription identifier GPSI or a subscription permanent identifier SUPI, and information of the H-PCF is obtained.

Optionally, the target SMF carries the second DNN when registering with the network storage function NRF.

Optionally, the device further comprises:

A switching unit, configured for the AMF to obtain a new replacement DNN from the H-PCF based on a local configuration policy change or a V-PCF change;

In the case where the new replacement DNN is identical to the second DNN, inserting an I-SMF as needed;

In case the new replacement DNN is different from the second DNN, PDU session reconstruction is initiated.

The access device in the embodiment of the present application may be an electronic device, such as an electronic device with an operating system, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device may be a core network device.

The access device provided in the embodiment of the present application can implement each process implemented by the method embodiment of Figure 2 and achieve the same technical effect. To avoid repetition, it will not be repeated here.

FIG13 is a second schematic diagram of the structure of the access device provided in the embodiment of the present application. As shown in FIG13 , the access device 1300 includes:

The first receiving unit 1310 is configured to receive an AM policy control update message sent by the AMF, where the AM policy control update message carries information of a first DNN and an H-PCF, where the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

A first N24 session establishing unit 1320 is configured for the V-PCF to check whether the information of the H-PCF is valid, and to send a second N24 session request to the H-PCF, wherein the second N24 session request carries the first DNN and terminal location related information;

The first N24 session response unit 1330 is configured to receive a second N24 session request response sent by the H-PCF, where the second N24 session request response carries the replacement DNN determined by the H-PCF;

A DNN decision unit 1340, configured to determine a second DNN according to other local strategies and the replacement DNN determined by the H-PCF;

An AM policy update response sending unit 1350 is configured for the V-PCF to send an AM policy control update response message to the AMF, wherein the AM policy control update response message carries the second DNN;

The second DNN is used by the AMF to determine the target SMF, so as to enable the terminal to access the client-side data center nearby through the target SMF;

The terminal has previously signed a nearby access service package at the H-PCF, and the H-PCF pre-configures a mapping relationship between each service area and a replacement DNN for each nearby access service package;

The replacement DNN determined by the H-PCF is determined based on the terminal location related information and the mapping relationship.

Optionally, the replacing the DNN includes: replacing a primary DNN and replacing a backup DNN.

Optionally, the device further comprises:

A second AM policy control establishment unit, configured to receive an AM policy control establishment message sent by the AMF;

A second N24 session establishing unit is configured to detect the existence of valid H-PCF information, create an N24 coupling, and send a first N24 session request to the H-PCF, where the first N24 session request is used to request the H-PCF to establish a terminal AM policy control;

The second N24 session response unit is used to receive the first N24 session request response sent by the H-PCF, and send an AM policy control establishment response message to the AMF. The AM policy control establishment response message carries the trigger rule of SMF selection change and the SMF selection indication identifier. The trigger rule of SMF selection change and the SMF selection indication identifier are used to indicate that when the AMF matches the terminal to create a new PDU session based on the specific DNN signed by the terminal, it is necessary to initiate a DNN replacement process to the PCF.

The access device in the embodiment of the present application may be an electronic device, such as an electronic device with an operating system, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device may be a core network device.

The access device provided in the embodiment of the present application can implement each process implemented by the method embodiment of Figure 3 and achieve the same technical effect. To avoid repetition, it will not be repeated here.

FIG14 is a third structural diagram of an access device provided in an embodiment of the present application. As shown in FIG14 , the access device 1400 includes:

The second receiving unit 1410 is configured to receive a second N24 session request sent by the V-PCF, where the second N24 session request carries the first DNN and information related to the terminal location; the first DNN is a dedicated DNN or a full-network DNN requested by the terminal;

A replacement DNN determining unit 1420 is configured to determine a replacement DNN for the terminal to access nearby according to the terminal location related information and a preconfigured mapping relationship;

The replacement DNN sending unit 1430 is configured to send a second N24 session request response to the V-PCF, where the second N24 session request response carries the replacement DNN determined by the H-PCF;

Among them, the terminal has previously signed a nearby access service package in the H-PCF; the H-PCF preconfigures the mapping relationship for each nearby access service package, and the mapping relationship is a mapping relationship between each service area and the replacement DNN.

Optionally, the replacing the DNN includes: replacing a primary DNN and replacing a backup DNN.

Optionally, the device further comprises:

A third receiving unit is used to receive a first N24 session request sent by the V-PCF, where the first N24 session request is used to request the H-PCF to establish a terminal AM policy control;

The third N24 session response unit is used to send a first N24 session request response to the V-PCF, wherein the first N24 session request response includes: a trigger rule for SMF selection change and an SMF selection indication identifier, wherein the trigger rule for SMF selection change and the SMF selection indication identifier are used to indicate that when a new PDU session is created based on a specific DNN signed by the terminal and the terminal is matched, a DNN replacement process needs to be initiated to the PCF.

The access device in the embodiment of the present application may be an electronic device, such as an electronic device with an operating system, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device may be a core network device.

The access device provided in the embodiment of the present application can implement each process implemented by the method embodiment of Figure 4 and achieve the same technical effect. To avoid repetition, it will not be repeated here.

FIG15 is a fourth structural diagram of an access device provided in an embodiment of the present application. As shown in FIG15 , the access device 1500 includes:

The fourth receiving unit 1510 is configured to receive a specific DNN determined by the home PCF/UDR according to the access location of the terminal and a preconfigured mapping relationship;

The first PCC policy execution unit 1520 is configured to execute the PCC policy based on the specific DNN, and activate the PDU session corresponding to the specific DNN for the terminal when receiving the first event reported by the UPF;

The first event is used to indicate that the destination address in the data message of the general DNN service of the terminal is the address corresponding to the specific DNN;

The terminal has previously signed a contract to activate a PCC policy on the home PCF/UDR of the terminal, and the PCC policy is used to indicate that when a destination address corresponding to a specific DNN is detected in a data message of a general DNN service of the terminal, the specific DNN is activated for the terminal;

The home PCF/UDR preconfigures a mapping relationship between each service area and a specific DNN.

Optionally, the device further comprises:

The UDM service discovery unit is used to perform unified data management UDM service discovery to the network storage function NRF, and obtain the session management subscription data of the terminal from the terminal's home UDM/UDR;

The third PCF service discovery unit is used to perform PCF service discovery to the NRF, and obtain the PCC policy subscribed by the terminal from the home PCF/UDR of the terminal.

Optionally, activating a PDU session of a dedicated DNN or a full-network DNN for the terminal includes:

Perform target SMF service discovery for dedicated DNN or network-wide DNN to NRF;

Use itself as the dedicated DNN of the terminal or the I-SMF of the whole network DNN, and select UPF as the dedicated DNN of the terminal or the I-UPF of the whole network DNN.

Optionally, the SMF is selected by the AMF for the universal DNN service of the terminal when the AMF receives a universal DNN activation request sent by the terminal.

Optionally, the specific DNN includes: a dedicated DNN or a full-network type DNN.

Optionally, the device further comprises:

A DNN receiving unit, configured to receive, by the SMF, an updated specific DNN determined by the PCF according to the latest access location of the terminal and a preconfigured mapping relationship when the roaming location of the terminal changes;

A second PCC policy execution unit, configured to execute the updated PCC policy based on the updated specific DNN, and re-establish a PDU session corresponding to the updated specific DNN for the terminal when receiving a second event reported by the UPF;

The second event is used to indicate that the destination address in the data message of the general DNN service of the terminal is the address corresponding to the updated specific DNN;

Among them, the PCF identifies the latest access location of the terminal through the AMF GUAMI information obtained through the N7 interface, and based on the pre-configured mapping relationship, re-sends new private network or full network DNN information to the intelligent diversion SMF according to the latest access location of the terminal.

Optionally, re-establishing a PDU session corresponding to the updated specific DNN for the terminal includes:

According to the triggering logic of the session state, the session is not reestablished when the terminal is in a connected state, and the PDU session is reestablished only when the terminal is in an idle state.

The access device in the embodiment of the present application may be an electronic device, such as an electronic device with an operating system, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device may be a core network device.

The access device provided in the embodiment of the present application can implement each process implemented by the method embodiment of Figure 9 and achieve the same technical effect. To avoid repetition, it will not be repeated here.

As shown in FIG16, the embodiment of the present application further provides a communication device 1600, including a processor 1601 and a memory 1602, and the memory 1602 stores a program or instruction that can be run on the processor 1601. For example, when the communication device 1600 is a terminal, the program or instruction is executed by the processor 1601 to implement the various steps of the above-mentioned access method embodiment, and can achieve the same technical effect. When the communication device 1600 is a network side device, the program or instruction is executed by the processor 1601 to implement the various steps of the above-mentioned access method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

Specifically, the embodiment of the present application further provides a network side device. As shown in Figure 17, the network side device 1700 includes: a processor 1701, a network interface 1702 and a memory 1703. The network interface 1702 is, for example, a common public radio interface (CPRI).

Specifically, the network side device 1700 of the embodiment of the present invention also includes: instructions or programs stored in the memory 1703 and executable on the processor 1701. The processor 1701 calls the instructions or programs in the memory 1703 to execute the methods executed by the modules shown in Figures 12 to 15 and achieve the same technical effect. To avoid repetition, it will not be repeated here.

An embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, each process of the above-mentioned access method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

The processor is the processor in the terminal described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk. In some examples, the readable storage medium may be a non-transient readable storage medium.

An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned access method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

The embodiment of the present application further provides a computer program/program product, which is stored in a storage medium, and is executed by at least one processor to implement the various processes of the above-mentioned access method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises one..." does not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the method and device in the embodiment of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted or combined. In addition, the features described with reference to certain examples may be combined in other examples.

Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment method can be implemented by means of a computer software product plus a necessary general hardware platform, and of course, it can also be implemented by hardware. The computer software product is stored in a storage medium (such as ROM, RAM, disk, CD, etc.), including several instructions to enable the terminal or network side device to execute the method described in each embodiment of the present application.

The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms of implementation methods without departing from the purpose of the present application and the scope of protection of the claims, and these implementation methods are all within the protection of the present application.

Claims (29)

1. An access method, comprising:

The access and mobile management function AMF receives a registration request sent by a terminal, and acquires subscription information of the terminal, wherein the subscription information comprises: the specific data network name DNN signed by the terminal;

The AMF determines that the conditions for establishing N15 connection are met based on the specific DNN subscribed by the terminal, and the AMF establishes N15 connection;

the AMF determines that the terminal roams, initiates a PCF service discovery process of a policy control function twice to a network storage function NRF, and obtains the information of a visiting place policy control function V-PCF and the information of a home place policy control function H-PCF;

the AMF sends an AM policy control establishing message to the H-PCF through the V-PCF;

The AMF receives an AM policy control establishing response message, wherein the AM policy control establishing response message carries SMF selection indication information, and the SMF selection indication information is used for indicating that the AMF needs to initiate a DNN replacement flow when detecting that the terminal establishes a PDU session based on a specific DNN subscribed by the terminal;

The AMF receives a PDU session establishment message sent by the terminal, wherein the PDU session establishment message carries a first DNN, and the first DNN is a special DNN or a full-network DNN requested by the terminal;

the AMF determines that the first DNN is in the specific DNN, and sends an AM policy control update message to the H-PCF through the V-PCF;

the AMF receives an AM policy control update response message, wherein the AM policy control update response message carries a second DNN;

The AMF determines a target SMF based on the second DNN, and the terminal is accessed to a client-side data center nearby through the target SMF;

Wherein the second DNN is determined by the V-PCF according to other local strategies and the alternative DNN determined by the H-PCF;

the method comprises the steps that a terminal signs up on an H-PCF in advance to access a service package, and the H-PCF pre-configures a mapping relation between each service area and a replacement DNN for each service package;

The replacement DNN determined by the H-PCF is determined based on the visiting area information of the terminal, the operator information accessed by the terminal or the position information of the terminal and the mapping relation.

2. The access method according to claim 1, wherein the specific DNN subscribed by the terminal further carries a special identification field triggering the N15 interface to be established;

The AMF determines that the condition for establishing the N15 connection is met based on the specific DNN subscribed by the terminal, and the AMF establishes the N15 connection and comprises the following steps:

If the AMF detects that the specific DNN subscribed by the terminal is contained in a locally pre-configured white list of the AMF, or the AMF detects that the specific DNN subscribed by the terminal contains a special identification field for triggering the N15 interface to be established, the AMF determines that the condition for establishing N15 connection is met;

And the AMF establishes N15 connection and deletes the special identification field in the specific DNN subscribed by the terminal.

3. The access method according to claim 1, wherein the specific DNN subscribed to by the terminal comprises a dedicated DNN or a full network-like DNN, and a list of alternative DNNs.

4. The access method of claim 1, wherein the replacement DNN determined by the H-PCF in consideration of disaster recovery comprises: replacement of primary DNN and replacement of backup DNN.

5. The access method according to claim 1, wherein the second DNN includes, in consideration of disaster recovery: primary DNN and backup DNN;

The AMF determines a target SMF based on the second DNN, and realizes that the terminal accesses a client-side data center nearby through the target SMF, and the AMF comprises the following steps:

The AMF determines a main SMF based on the main DNN, and the terminal is accessed to a client side data center nearby through the main SMF;

and after the main SMF fails, determining a standby SMF based on the standby DNN, and realizing that the terminal is accessed to the client-side data center nearby through the standby SMF.

6. The access method of claim 1, wherein the determining that the terminal is roaming is preceded by the method further comprising:

and the AMF judges whether the terminal has inter-provincial roaming according to the information of the home data management equipment (UDM) of the terminal.

7. The access method according to claim 1 or 6, characterized in that the method further comprises:

And if the terminal is determined not to roam, initiating a PCF service discovery process to the visiting place NRF to acquire the information of the local PCF.

8. The access method according to claim 1, wherein the step of initiating the network storage function NRF with the twice policy control function PCF service discovery procedure to obtain the information of the visited policy control function V-PCF and the information of the home policy control function H-PCF includes:

the V-PCF is discovered through a service scope SSP or a service name, and information of the V-PCF is obtained;

And discovering the H-PCF through a general public subscription identifier GPSI or a subscription permanent identifier SUPI, and acquiring information of the H-PCF.

9. The access method according to claim 1, characterized in that the target SMF carries the second DNN when registering with a network storage function NRF.

10. The access method of claim 1, wherein the method further comprises:

The AMF acquires new replacement DNN from the H-PCF based on local configuration strategy change or V-PCF change;

Inserting an I-SMF on demand, if the new replacement DNN is the same as the second DNN;

And in case the new replacement DNN is different from the second DNN, initiating PDU session reestablishment.

11. An access method, comprising:

The method comprises the steps that a visiting place policy control function V-PCF receives an AM policy control update message sent by an AMF, wherein the AM policy control update message carries information of a first DNN and H-PCF, and the first DNN is a special DNN or a full-network DNN requested by a terminal;

the V-PCF checks that the information of the H-PCF is valid, and sends a second N24 session request to the H-PCF, wherein the second N24 session request carries the first DNN and the terminal position related information;

The V-PCF receives a second N24 session request response sent by the H-PCF, wherein the second N24 session request response carries the replacement DNN determined by the H-PCF;

The V-PCF determines a second DNN according to other local strategies and the replacement DNN determined by the H-PCF;

the V-PCF sends an AM policy control update response message to the AMF, wherein the AM policy control update response message carries the second DNN;

The second DNN is used for determining a target SMF by the AMF so as to realize that the terminal accesses a client-side data center nearby through the target SMF;

the method comprises the steps that a terminal signs up on an H-PCF in advance to access a service package, and the H-PCF pre-configures a mapping relation between each service area and a replacement DNN for each service package;

and the replacement DNN determined by the H-PCF is determined based on the terminal position related information and the mapping relation.

12. The access method of claim 11, wherein the replacement DNN comprises: replacement of primary DNN and replacement of backup DNN.

13. The access method of claim 11, wherein the method further comprises:

The V-PCF receives an AM policy control establishing message sent by an AMF;

The V-PCF detects that effective H-PCF information exists, an N24 coupling is established, and a first N24 session request is sent to the H-PCF, wherein the first N24 session request is used for requesting the H-PCF to establish terminal AM policy control;

The V-PCF receives a first N24 session request response sent by the H-PCF, sends an AM policy control establishment response message to the AMF, wherein the AM policy control establishment response message carries a trigger rule of SMF selection change and an SMF selection indication mark, and the trigger rule of SMF selection change and the SMF selection indication mark are used for indicating that when the AMF is matched with a specific DNN new PDU session signed by the terminal based on the terminal, a DNN replacement process needs to be initiated to the PCF.

14. An access method, comprising:

The home policy control function H-PCF receives a second N24 session request sent by the V-PCF, wherein the second N24 session request carries the first DNN and the terminal position related information; the first DNN is a special DNN or a full-network DNN requested by a terminal;

the H-PCF determines the replacement DNN accessed nearby by the terminal according to the relevant information of the terminal position and the preconfigured mapping relation;

The H-PCF sends a second N24 session request response to the V-PCF, wherein the second N24 session request response carries the replacement DNN determined by the H-PCF;

the terminal has contracted in the H-PCF in advance and is accessed to a service package; the H-PCF pre-configures the mapping relation for each nearby access service package, wherein the mapping relation is the mapping relation between each service area and the replacement DNN.

15. The access method of claim 14, wherein the replacement DNN comprises: replacement of primary DNN and replacement of backup DNN.

16. The access method of claim 14, wherein the method further comprises:

The H-PCF receives a first N24 session request sent by the V-PCF, wherein the first N24 session request is used for requesting the H-PCF to establish terminal AM policy control;

The H-PCF sends a first N24 session request response to the V-PCF, wherein the first N24 session request response comprises the following steps: and when the SMF selection change trigger rule and the SMF selection indication mark are used for indicating that the PDU session is matched with the specific DNN newly-built PDU session subscribed by the terminal based on the terminal, a DNN replacement process needs to be initiated to the PCF.

17. An access method, comprising:

The session management function SMF receives a specific DNN determined by the attribution PCF/UDR according to the access position of the terminal and a preconfigured mapping relation;

The SMF executes PCC strategy based on the specific DNN, and activates PDU session corresponding to the specific DNN for the terminal under the condition of receiving a first event reported by UPF;

The first event is used for indicating that a destination address in a data message of the universal DNN service of the terminal is an address corresponding to a specific DNN;

The terminal signs a subscription to open a PCC policy on a attributive PCF/UDR of the terminal in advance, wherein the PCC policy is used for indicating that a specific DNN is activated for the terminal when a data message of a general DNN service of the terminal detects that a destination address is an address corresponding to the specific DNN;

the home PCF/UDR pre-configures the mapping relation between each service area and a specific DNN.

18. The access method of claim 17, wherein the method further comprises:

The SMF executes Unified Data Management (UDM) service discovery to a network storage function (NRF) and acquires session management subscription data of the terminal from a home UDM/UDR of the terminal;

And the SMF executes PCF service discovery to the NRF and acquires the PCC policy subscribed by the terminal from the home PCF/UDR of the terminal.

19. The access method according to claim 17, wherein the activating the PDU session corresponding to the specific DNN for the terminal includes:

The SMF executes target SMF service discovery of special DNN or full network DNN to NRF;

The SMF takes the SMF as the I-SMF of the special DNN or the full-network DNN of the terminal, and selects the UPF as the I-UPF of the special DNN or the full-network DNN of the terminal.

20. The access method of claim 17, wherein the SMF is selected for a generic DNN service of the terminal upon receipt of a generic DNN activation request sent by the terminal by the AMF.

21. The access method of claim 17, wherein the particular DNN comprises: dedicated DNN or full network-like DNN.

22. The access method according to any of claims 17-21, characterized in that the method further comprises:

when the roaming place of the terminal changes, the SMF receives updated specific DNN determined by PCF according to the latest access position of the terminal and a preconfigured mapping relation;

The SMF executes an updated PCC strategy based on the updated specific DNN, and reestablishes a PDU session corresponding to the updated specific DNN for the terminal under the condition of receiving a second event reported by the UPF;

the second event is used for indicating that a destination address in a data message of the universal DNN service of the terminal is an address corresponding to the updated specific DNN;

The PCF identifies the latest access position of the terminal through AMF GUAMI information acquired by an N7 interface, and issues new private network or full network DNN information to the intelligent shunt SMF again according to the latest access position of the terminal based on a preset mapping relation.

23. The access method according to claim 22, wherein reestablishing the PDU session for the updated specific DNN for the terminal comprises:

according to the triggering logic of the session state, the session reconstruction is not carried out when the terminal is in a connection state, and the PDU session is only reconstructed when the terminal is in an idle state.

24. An access device, comprising:

the subscription information acquisition unit is used for receiving a registration request sent by a terminal and acquiring subscription information of the terminal, wherein the subscription information comprises: the specific data network name DNN signed by the terminal;

An N15 establishing unit, configured to determine that an N15 connection establishment condition is satisfied based on the specific DNN subscribed by the terminal, and establish an N15 connection;

The first PCF service discovery unit is used for determining that the terminal roams and initiating a PCF service discovery process with a policy control function twice to the NRF to obtain the information of the visited policy control function V-PCF and the information of the home policy control function H-PCF;

A first AM policy control establishing unit, configured to send an AM policy control establishing message to the H-PCF through the V-PCF;

An AM policy control establishing response unit, configured to receive an AM policy control establishing response message, where the AM policy control establishing response message carries SMF selection indication information, where the SMF selection indication information is configured to instruct the AMF to initiate a DNN replacement procedure when detecting that the terminal establishes a PDU session based on a specific DNN subscribed by the terminal;

A session establishment unit, configured to receive a PDU session establishment message sent by the terminal, where the PDU session establishment message carries a first DNN, and the first DNN is a dedicated DNN or a full network DNN requested by the terminal;

An AM policy updating unit, configured to determine that the first DNN is in the specific DNN, and send an AM policy control update message to the H-PCF through the V-PCF;

an AM policy update response unit, configured to receive an AM policy control update response message, where the AM policy control update response message carries a second DNN;

The SMF determining unit is used for determining a target SMF based on the second DNN, and accessing the terminal to the client side data center nearby through the target SMF;

Wherein the second DNN is determined by the V-PCF according to other local strategies and the alternative DNN determined by the H-PCF;

the method comprises the steps that a terminal signs up on an H-PCF in advance to access a service package, and the H-PCF pre-configures a mapping relation between each service area and a replacement DNN for each service package;

The replacement DNN determined by the H-PCF is determined based on the visiting area information of the terminal, the operator information accessed by the terminal or the position information of the terminal and the mapping relation.

25. An access device, comprising:

The first receiving unit is used for receiving an AM policy control update message sent by an AMF, wherein the AM policy control update message carries information of a first DNN and an H-PCF, and the first DNN is a special DNN or a full-network DNN requested by a terminal;

A first N24 session establishment unit, configured to check, by using the V-PCF, that information of the H-PCF is valid, and send a second N24 session request to the H-PCF, where the second N24 session request carries the first DNN and information related to a terminal location;

A first N24 session response unit, configured to receive a second N24 session request response sent by the H-PCF, where the second N24 session request response carries the replacement DNN determined by the H-PCF;

the DNN decision unit is used for determining a second DNN according to the local other strategies and the replacement DNN determined by the H-PCF;

An AM policy update response sending unit, configured to send an AM policy control update response message to the AMF by using the V-PCF, where the AM policy control update response message carries the second DNN;

The second DNN is used for determining a target SMF by the AMF so as to realize that the terminal accesses a client-side data center nearby through the target SMF;

the method comprises the steps that a terminal signs up on an H-PCF in advance to access a service package, and the H-PCF pre-configures a mapping relation between each service area and a replacement DNN for each service package;

and the replacement DNN determined by the H-PCF is determined based on the terminal position related information and the mapping relation.

26. An access device, comprising:

The second receiving unit is used for receiving a second N24 session request sent by the V-PCF, wherein the second N24 session request carries the first DNN and the terminal position related information; the first DNN is a special DNN or a full-network DNN requested by a terminal;

A replacement DNN determining unit, configured to determine a replacement DNN that is accessed by the terminal nearby according to the terminal position related information and a preconfigured mapping relationship;

a replacement DNN sending unit, configured to send a second N24 session request response to the V-PCF, where the second N24 session request response carries the replacement DNN determined by the H-PCF;

the terminal has contracted in the H-PCF in advance and is accessed to a service package; the H-PCF pre-configures the mapping relation for each nearby access service package, wherein the mapping relation is the mapping relation between each service area and the replacement DNN.

27. An access device, comprising:

A fourth receiving unit, configured to receive a specific DNN determined by the home PCF/UDR according to the access location of the terminal and a preconfigured mapping relationship;

A first PCC policy executing unit, configured to execute a PCC policy based on the specific DNN, and activate, for the terminal, a PDU session corresponding to the specific DNN when a first event reported by a UPF is received;

The first event is used for indicating that a destination address in a data message of the universal DNN service of the terminal is an address corresponding to a specific DNN;

The terminal signs a subscription to open a PCC policy on a attributive PCF/UDR of the terminal in advance, wherein the PCC policy is used for indicating that a specific DNN is activated for the terminal when a data message of a general DNN service of the terminal detects that a destination address is an address corresponding to the specific DNN;

the home PCF/UDR pre-configures the mapping relation between each service area and a specific DNN.

28. A network side device comprising a processor and a memory storing a program or instructions executable on the processor, the program or instructions implementing the steps of the access method according to any one of claims 1 to 10, or the steps of the access method according to any one of claims 11 to 13, or the steps of the access method according to any one of claims 14 to 16, or the steps of the access method according to any one of claims 17 to 23.

29. A readable storage medium, characterized in that the readable storage medium has stored thereon a program or instructions which, when executed by a processor, implements the access method of any of claims 1 to 10, or implements the access method of any of claims 11 to 13, or implements the access method of any of claims 14 to 16, or implements the access method of any of claims 17 to 23.