Method and apparatus for determining target eir

Abstract

The embodiment of the application provides a method and device for determining a target EIR. The method is applied to an AMF and includes the following steps: determining, based on the state of deployment of multiple EIRs, whether the multiple EIRs are centrally deployed or globally deployed; if the multiple EIRs are centrally deployed, sending a first request message to an NRF to determine a target EIR that matches user equipment information carried in the first request message; the NRF locally stores user equipment information served by each EIR of the multiple EIRs; and if the multiple EIRs are globally deployed, determining a target EIR based on a link state monitoring table. The link state monitoring table includes the IP address, port number and service state of each EIR of the multiple EIRs. The method for determining a target EIR provided by the embodiment of the application can meet the needs of different deployment scenarios of EIRs, ensure the accuracy of EIR device selection, and ensure timely switching in the case of link failure.

Description

Technical Field

[0001] This application relates to the field of communication equipment technology, and in particular to a method and apparatus for determining a target EIR. Background Technology

[0002] In 5G private network scenarios, for nationwide application industries, there are situations where terminals deployed at a specific central location are managed by that central location itself. The nationwide network only handles basic communication processes and does not manage the terminals. Therefore, Unified Data Management (UDM) and Equipment Identity Register (EIR) need to be deployed separately. Currently, related technologies primarily support multiple deployments of UDM. For scenarios with multiple EIR deployments, there is a lack of technical support to correctly select the appropriate EIR device based on different terminal information, leading to verification failures during terminal access and preventing the terminal from using network services.

[0003] In addition, there is another method for globally deploying UDM, EIR, and Network Repository Function (NRF) devices. In this method, where globally shared devices are deployed on global nodes, to reduce network complexity, the EIR devices are chosen not to register with the NRF. This means that each Access and Mobility Management Function (AMF) device at the centralized point needs to be pre-configured to connect to the global EIR device. In a 5G service-oriented architecture, service anomaly notifications are typically detected and communicated to network elements subscribed to the service status via the NRF. Therefore, in this scenario, since the EIR does not register with the NRF, it cannot obtain the network element status through the original service subscription notification method. When the EIR fails, the AMF cannot quickly detect it, leading to verification failure and a decrease in access success rate.

[0004] The current protocol provisions apply to public networks or scenarios where PEI device verification is not strict, and can be said to be applicable to 99% of current scenarios. However, for specific industries with strong PEI verification requirements, and for scenarios where EIRs are deployed in a decentralized manner through centralized points, the current protocol definition cannot accurately locate the corresponding EIR devices. In scenarios where EIRs are deployed globally, no NRF registration is required, making it impossible to quickly obtain the status of network elements, resulting in a decrease in terminal access success rate. These issues have become urgent technical problems to be solved in this field. Summary of the Invention

[0005] This application provides a method for determining a target EIR, which solves the technical problem in related technologies where the EIR device cannot be correctly selected for the service or the EIR fault cannot be quickly detected, resulting in verification failure during terminal access, and the terminal being unable to use network services or the access success rate being reduced.

[0006] In a first aspect, embodiments of this application provide a method for determining a target EIR, applied to an AMF, comprising:

[0007] Based on the status of multiple EIR deployments, it is determined whether the multiple EIRs are centrally deployed or globally deployed;

[0008] If the multiple EIRs are deployed at a centralized point, a first request message is sent to the NRF to determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the multiple EIRs.

[0009] If the multiple EIRs are deployed globally, the target EIR is determined based on the link status monitoring table; the link status monitoring table includes the IP address, port number and service status of each of the multiple EIRs.

[0010] Optionally, the user equipment information to be authenticated is represented by a first field added to the first request message, which is used to represent the PEI corresponding to the user equipment to be authenticated.

[0011] Optionally, if the multiple EIRs are deployed globally, the target EIR is determined based on the link state monitoring table, including:

[0012] When each of the plurality of EIRs establishes a connection with each of the central points, the link status monitoring table is initialized based on the IP address, port number and initial value of service status corresponding to each of the plurality of EIRs.

[0013] The link status monitoring table is updated based on the feedback messages from the received periodic probe messages;

[0014] Based on the updated link status monitoring table, the EIR that can establish a valid link with any of the multiple EIRs is identified as the target EIR.

[0015] Optionally, determining the EIR that can establish a valid link with any of the plurality of EIRs, based on the updated link state monitoring table, as the target EIR, includes:

[0016] Based on the principle of prioritizing the primary EIR, the service status of the primary EIR among the multiple EIRs is determined;

[0017] If the service status of the primary EIR is normal, then the primary EIR is determined to be the target EIR;

[0018] If the service status of the primary EIR is abnormal, the target EIR is determined based on the service status of the backup EIR among the multiple EIRs.

[0019] If the service status of the primary EIR is unavailable, then the target EIR is determined based on the service status of the backup EIR among the multiple EIRs;

[0020] The plurality of EIRs includes a primary EIR and a backup EIR.

[0021] Optionally, if the service status of the primary EIR is abnormal, determining the target EIR based on the service status of the backup EIR among the plurality of EIRs includes:

[0022] If the service status of the primary EIR is abnormal, determine the service status of the backup EIR among the plurality of EIRs;

[0023] If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR;

[0024] If the service status of the backup EIR is abnormal or unavailable, then the primary EIR is determined to be the target EIR.

[0025] Optionally, if the service status of the primary EIR is unavailable, determining the target EIR based on the service status of the backup EIRs among the plurality of EIRs includes:

[0026] If the service status of the primary EIR is unavailable, determine the service status of the backup EIR among the plurality of EIRs;

[0027] If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR;

[0028] If the service status of the backup EIR is abnormal, then the backup EIR is determined to be the target EIR;

[0029] If the service status of the backup EIR is unavailable, then it is determined that there is no target EIR.

[0030] Secondly, embodiments of this application provide a method for determining a target EIR, applied to an EIR, comprising:

[0031] When the EIR is deployed at a centralized point, the EIR sends a registration message to the NRF, and the registration message includes first information for representing user equipment information of the EIR service;

[0032] When the EIR is deployed globally, based on the probe messages periodically sent by the AMF, the EIR sends a feedback message, which includes the EIR's IP address, port number, and service status, and is used to update the AMF's link state monitoring table.

[0033] Optionally, the method further includes:

[0034] If the EIR is deployed at a centralized point, and the user equipment information of the EIR service changes, the EIR sends the updated first information to the NRF.

[0035] Optionally, the first information is represented by a second field added to the registration message. The second field is used to define the range of the user equipment's PEI, including the starting point of the PEI value, the ending point of the PEI value, and the pattern rules of the PEI value.

[0036] Optionally, the starting point, ending point, and pattern rules of the PEI value are all represented by regular expressions.

[0037] Thirdly, embodiments of this application provide a method for determining a target EIR, applied to NRF, including:

[0038] Based on the first request message sent by the AMF and the first set, a first response message corresponding to the first request message is determined; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated;

[0039] The first set includes user equipment information for each EIR service in multiple EIRs.

[0040] Optionally, the method for determining the first set includes:

[0041] In the case where the multiple EIRs are deployed at a centralized point, a first set is determined based on the registration messages sent by each of the multiple EIRs; the registration messages include first information for representing user equipment information of the EIR service; the first set is composed of the first information included in the registration messages sent by all the EIRs.

[0042] Fourthly, embodiments of this application also provide an AMF, including a memory, a transceiver, and a processor:

[0043] A memory for storing computer programs; a transceiver for sending and receiving data under the control of the processor; and a processor for reading the computer programs from the memory and executing the method for determining the target EIR as described in the first aspect above.

[0044] Fifthly, embodiments of this application also provide an EIR, including a memory, a transceiver, and a processor:

[0045] A memory for storing computer programs; a transceiver for sending and receiving data under the control of the processor; and a processor for reading the computer programs from the memory and executing the method for determining the target EIR as described in the second aspect above.

[0046] Sixthly, embodiments of this application also provide an NRF, including a memory, a transceiver, and a processor:

[0047] A memory for storing computer programs; a transceiver for sending and receiving data under the control of the processor; and a processor for reading the computer programs from the memory and executing the method for determining the target EIR as described in the third aspect above.

[0048] In a seventh aspect, embodiments of this application also provide an apparatus for determining a target EIR, applied to an AMF, comprising:

[0049] The first determining module is used to determine whether the multiple EIRs are centrally deployed or globally deployed based on the status of the multiple EIRs.

[0050] The centralization module is used to send a first request message to the NRF if the multiple EIRs are deployed at a centralization point, so that the NRF can determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the multiple EIRs.

[0051] The global point module is used to determine the target EIR based on the link status monitoring table if the multiple EIRs are deployed as global points; the link status monitoring table includes the IP address, port number and service status of each of the multiple EIRs.

[0052] Eighthly, embodiments of this application also provide an apparatus for determining a target EIR, applied to an EIR, comprising:

[0053] The first sending module is configured to, when the EIR is deployed at a central point, send a registration message to the NRF, wherein the registration message includes first information representing user equipment information of the EIR service;

[0054] The second sending module is used to send a feedback message to the EIR based on the probe messages periodically sent by the AMF when the EIR is deployed as a global point. The feedback message includes the IP address, port number and service status of the EIR, and is used to update the link status monitoring table of the AMF.

[0055] Ninthly, embodiments of this application also provide an apparatus for determining a target EIR, applied to NRF, comprising:

[0056] The second determining module is used to determine a first response message corresponding to the first request message based on the first request message sent by the received AMF and a first set; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated;

[0057] The first set includes user equipment information for each EIR service in multiple EIRs.

[0058] In a tenth aspect, embodiments of this application also provide a computer-readable storage medium storing a computer program configured to cause a computer to perform the method for determining a target EIR as described in the first aspect, or the method for determining a target EIR as described in the second aspect, or the method for determining a target EIR as described in the third aspect.

[0059] Eleventhly, embodiments of this application also provide a communication device, wherein the communication device stores a computer program, the computer program being configured to cause the communication device to perform the method for determining a target EIR as described in the first aspect, or to perform the method for determining a target EIR as described in the second aspect, or to perform the method for determining a target EIR as described in the third aspect.

[0060] In a twelfth aspect, embodiments of this application also provide a processor-readable storage medium storing a computer program configured to cause a processor to perform the method for determining a target EIR as described in the first aspect, or the method for determining a target EIR as described in the second aspect, or the method for determining a target EIR as described in the third aspect.

[0061] In a thirteenth aspect, embodiments of this application also provide a chip product, wherein the chip product stores a computer program, the computer program being configured to cause the chip product to perform the method for determining a target EIR as described in the first aspect above, or to perform the method for determining a target EIR as described in the second aspect above, or to perform the method for determining a target EIR as described in the third aspect above.

[0062] The method for determining a target EIR provided in this application dynamically determines the EIR device that matches the user equipment information of all EIR services obtained locally after registration with the NRF, based on different EIR deployment scenarios. Alternatively, it determines the EIR with a normal service status based on the service status of all EIRs stored locally by the AMF, and uses this EIR as the target EIR for the terminal access process to complete authentication. This method enables fast and accurate locating of the service EIR or ensures the validity of the link status, making link selection more efficient, improving the success rate of the process, and avoiding situations where the terminal access is abnormal and cannot use network services. Attached Figure Description

[0063] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0064] Figure 1 This is a schematic diagram of the interconnection between the central point, the core network, and the dedicated bearer network provided in the embodiments of this application;

[0065] Figure 2 This is a schematic diagram of a network structure where the EIR is deployed at a centralized point, as provided in an embodiment of this application.

[0066] Figure 3 This is a schematic diagram of a network structure where the EIR is deployed globally, as provided in an embodiment of this application.

[0067] Figure 4 This is a flowchart illustrating the two-way authentication process during terminal access in related technologies;

[0068] Figure 5 This is a flowchart illustrating the registration process for network storage functions in related technologies;

[0069] Figure 6 This is a flowchart illustrating the AMF process for discovering EIRs in related technologies;

[0070] Figure 7 This is one of the flowcharts illustrating the service subscription discovery process in related technologies;

[0071] Figure 8 This is the second flowchart illustrating the service subscription discovery process in related technologies;

[0072] Figure 9 This is one of the flowcharts illustrating the method for determining a target EIR provided in the embodiments of this application;

[0073] Figure 10 This is a schematic diagram of the overall process for determining the target EIR provided in the embodiments of this application;

[0074] Figure 11 This is the second schematic diagram of the implementation process of the method for determining the target EIR provided in the embodiments of this application;

[0075] Figure 12 This is the third flowchart illustrating the method for determining a target EIR provided in the embodiments of this application;

[0076] Figure 13 This is a schematic diagram of an AMF structure provided in an embodiment of this application;

[0077] Figure 14 This is a schematic diagram of the structure of an EIR provided in an embodiment of this application;

[0078] Figure 15 This is a schematic diagram of an NRF structure provided in an embodiment of this application;

[0079] Figure 16 This is one of the structural schematic diagrams of the device for determining a target EIR provided in the embodiments of this application;

[0080] Figure 17 This is a second schematic diagram of the device for determining the target EIR provided in the embodiments of this application;

[0081] Figure 18 This is the third schematic diagram of the device for determining the target EIR provided in the embodiments of this application. Detailed Implementation

[0082] In the embodiments of this application, the term "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following associated objects have an "or" relationship.

[0083] In the embodiments of this application, the term "multiple" refers to two or more, and other quantifiers are similar.

[0084] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0085] To help understand the solutions of the embodiments of this application, the following will briefly introduce the relevant concepts that may be involved in this application:

[0086] In some private network application scenarios, the corresponding scope may involve the entire country. For example, in the railway scenario, the core network construction is concentrated in a few cities, which can be understood as a regional approach or a centralized point model.

[0087] In this scenario, each centralization point needs to deploy independent core network elements. The centralization points and their corresponding core networks can interconnect via a dedicated bearer network, such as... Figure 1 As shown.

[0088] For nationwide application industries, some centralized points may only manage terminals issued by that specific point, while the nationwide bearer network only handles basic communication processes and does not manage the terminals. Therefore, Unified Data Management (UDM) and Equipment Identity Register (EIR) devices may need to be managed separately. A network structure diagram showing UDM and EIR deployed separately, with EIR deployed independently at each centralized point, is shown below. Figure 2 As shown.

[0089] In a multi-point deployment scenario using UDM and EIR, when a terminal moves from one centralized point to another, the terminal access requires authentication, including authentication of the Universal Subscriber Identity Module (USIM) card and authentication of the terminal / User Equipment (UE). These authentications are performed by the UDM and EIR devices, respectively. In other words, the UDM stores the subscription data of terminals at that centralized point, while the EIR stores the configured (published) terminal equipment information at that centralized point. Errors in either of these pieces of information will affect the terminal's ability to use network services.

[0090] According to the current protocol definition, UDM multi-deployment is supported. However, for EIR multi-deployment scenarios, the current protocol cannot support the correct selection of EIR devices for services based on different terminal information, resulting in verification failure and the terminal being unable to use network services.

[0091] In addition, there is another deployment scenario where UDM, EIR, and Network Repository Function (NRF) devices can be deployed and managed globally, such as... Figure 3 As shown.

[0092] In a globally shared device deployment on global nodes, to reduce network complexity, the EIR device is not registered with the NRF. This means that the AMF devices at each centralized point need to be pre-configured to connect to the EIR device deployed at the global node. In a 5G service-oriented architecture, service anomaly notifications are typically detected by the NRF and sent to network elements with subscribed services, informing these elements of the corresponding subscription service status. Therefore, in this scenario, since the EIR is not registered with the NRF, it cannot obtain the network element status through the original service subscription notification method. When the primary EIR fails, the AMF cannot quickly detect it, leading to verification failure and a reduced access success rate.

[0093] In summary, the embodiments of this application provide a method for determining a target EIR, which can meet the needs of different deployment scenarios, ensure the accuracy of EIR device selection, and ensure link effectiveness.

[0094] The terminal access process requires two-way authentication of the USIM card and verification of the EIR device's legitimacy. The process is clearly defined in TS23.502 of the 3rd Generation Partnership Project (3GPP) protocol, and the specific flowchart is as follows: Figure 4 As shown.

[0095] Figure 4 Step 12 is the device information verification process, which is the process by which the AMF verifies the PEI information of the terminal after obtaining it from the terminal.

[0096] Due to the introduction of service-oriented features in 5G systems, each network element needs to initiate a service registration process with the NRF (Network RF) to register all the services or features it supports, including all services that the network element can invoke and the scope of those services. If using services from other network elements, a service discovery process needs to be initiated with the NRF. The NRF then searches its local repository for services that meet the criteria and returns them to the requester. Based on the returned results, the requester invokes the services of other network elements. This process is clearly defined in the 3GPP TS29.510 protocol, and the registration process is as follows: Figure 5 As shown, the Network Service Consumer (NF) sends NFProfile information to the Network Storage Function (NRF) via a PUT request. The NRF responds with a 201 status code, indicating successful NFProfile creation; or a 4XX / 5XX status code, indicating a problem during creation, along with a detailed description of the problem; or a 3XX status code. The status codes are typically 3 digits long, with 4XX, 5XX, and 3XX representing status codes starting with 4, 5, and 3, respectively.

[0097] The information carried in the registration message from the EIR device to the NRF is shown in Table 1. As can be seen from Table 1, the UE device information PEI under the jurisdiction of the EIR is not included in the registration message.

[0098] Table 1

[0099] nfInstanceId NfInstanceId M 1 NF instance ID nfType NFType M 1 The NF type and the EIR type are 5G-EIR. nfStatus NFStatus M 1 NF instance status nfInstanceName string O 0..1 NF instance name plmnList array(PlmnId) C 1..N List of PLMNs sNssais array(ExtSnssai) O 1..N Supported slice information perPlmnSnssaiList array(PlmnSnssai) O 1..N Supported slices and their correspondence with PLMN nsiList array(string) O 1..N The list of supported NSIs is not included; not including it indicates that all are supported. fqdn Fqdn C 0..1 FQDN Information IPv4 Addresses array(Ipv4Addr) C 1..N IPv4 address information IPv6 Addresses array(Ipv6Addr) C 1..N IPv6 address information capacity integer O 0..1 Weight information load integer O 0..1 Load information loadTimeStamp DateTime O 0..1 Timestamp of the last time load information was reported to NRF locality string O 0..1 Location information of NF instances defined by the operator priority integer O 0..1 Select priority

[0100] AMF discovers (finds) EIRs through NRF and finds suitable EIRs to serve it, such as Figure 6 As shown. In the currently serving public terrestrial mobile network, the Network Service Consumer (NF) sends a query parameter to the Network Storage Function (NRF) via a GET request. The NRF responds with a 200 status code, indicating that the corresponding result was found, and returns the result information along with the status code. Alternatively, it may respond with a 4XX / 5XX status code, indicating that there was a problem in the query process, along with a detailed description of the problem, or a 3XX status code. The status code is typically 3 digits long; 4XX, 5XX, and 3XX represent status codes starting with 4, 5, and 3, respectively.

[0101] The specific parameters of the query request message sent by AMF to NRF are shown in Table 2.

[0102] Table 2

[0103]

[0104] In the 3GPP protocol, after discovering a service, a subscription process needs to be initiated with the NRF to subscribe to the service's status. When a service encounters an anomaly, the NRF notifies the subscribed network element. For the REST protocol of the service-oriented interface, apart from heartbeat messages between each service and the NRF, there are no periodic monitoring messages between the client and server of other services.

[0105] Figure 7 and Figure 8This is a flowchart illustrating the service subscription discovery process in related technologies. In the current public terrestrial mobile network, the Network Service Consumer (NF) and the Network Storage Function (NRF) communicate via POST requests and corresponding feedback status codes to achieve service subscription discovery. In scenarios where network elements are not registered with the NRF, primarily in applications integrated with 5G, they cannot perceive service status changes through NRF subscription notifications. Furthermore, the connection between two network elements is typically established via the HTTP protocol, and can be either a short or long connection. For short connections, connection establishment is triggered when a message is sent; if there are link problems, message sending may be delayed or fail. For long connections, if a link problem occurs, the original link is directly disconnected, and the connection is re-attempted when a message is sent again. Moreover, in the event of a link failure, upper-layer applications cannot be notified immediately, leading to message sending failures and a decrease in the success rate of terminal access.

[0106] Under the current 3GPP definition, it is applicable to public networks or scenarios where PEI verification of terminal devices is not strict. It can be said to be applicable to most current scenarios. However, for specific industries, there is a strong demand for PEI verification. For scenarios where EIRs are deployed in a distributed (centralized) manner, the current protocol definition cannot accurately find the corresponding EIR device by using NRF selection. For scenarios where EIRs are deployed globally, i.e., scenarios where NRF registration is not required, it is necessary to quickly determine the effective link to ensure timely switching when encountering a faulty link.

[0107] In light of the aforementioned problems in related technologies, embodiments of this application propose that, in different scenarios, EIR device registration involves reporting the PEI information of the terminal devices it serves, or configuring the link status table of the EIR locally in the AMF and updating it in real time, thereby accurately selecting the EIR device to which the terminal belongs and ensuring that the corresponding link is valid.

[0108] Figure 9 This is one of the flowcharts illustrating a method for determining a target EIR provided in this application embodiment. This method can be applied to, for example... Figure 9 As shown, the method includes:

[0109] Step 901: Based on the status of multiple EIR deployments, determine whether the multiple EIRs are centrally deployed or globally deployed;

[0110] Step 902: If the multiple EIRs are deployed at a centralized point, a first request message is sent to the NRF to determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the multiple EIRs.

[0111] Step 903: If the multiple EIRs are deployed globally, then the target EIR is determined based on the link status monitoring table; the link status monitoring table includes the IP address, port number and service status of each of the multiple EIRs.

[0112] Specifically, in 5G private networks, the Equipment Identifier (EIR) can be deployed in different ways. For example, one EIR can be deployed at each central point, responsible for all terminals published at that central point, and can store the user equipment information corresponding to these terminals. Alternatively, multiple EIRs can be deployed globally, including at least one primary EIR and one backup EIR, with each EIR managing all terminals published at the central point. Depending on the EIR deployment, during the access process, terminals need to verify the legitimacy of the EIR device during two-way authentication. However, there is currently no solution in the relevant technologies for accurately determining the EIR device corresponding to a terminal.

[0113] Therefore, this application proposes that, in the case of EIR deployment as a centralized point, during the registration process of EIR devices with the NRF, the information of the EIR device and the terminals served by that EIR device should be sent to the NRF. In this way, the NRF will obtain information about all EIR devices and the terminals served by each EIR device. This achieves the goal of dynamic synchronization and network-wide sharing in multi-EIR deployment scenarios.

[0114] During terminal access, the terminal, acting as a user equipment to be authenticated, sends a registration request to the AMF. During the AMF's discovery of the EIR, the AMF has already obtained the user equipment information to be authenticated, and this information uniquely identifies the terminal. Various representation methods are possible, such as the International Mobile Equipment Identity (IMEI) or the Permanent Equipment Identifier (PEI). The AMF sends a first request message to the NRF to perform the EIR discovery process. This first request message carries the user equipment information corresponding to the terminal, i.e., the user equipment information to be authenticated. Using this user equipment information, the NRF searches and matches it against the user equipment information of all EIR services stored locally. This matches the target EIR, and the terminal's two-way authentication process is completed through this target EIR. The user equipment information of all EIR services stored locally by the NRF is obtained by each EIR reporting its service's user equipment information to the NRF during the registration process, thus providing the NRF with the user equipment information for all EIR services.

[0115] When EIRs are deployed globally, they do not register with the NRF. The AMF needs to statically configure EIR device information and their corresponding status locally. EIR device information can be represented by IP address, IP address and port number, or device identifier, while the EIR device status can be represented by service status, connection status, etc. Connection status refers to the link status between the EIR device and the AMF. A normal link status indicates the EIR device is in a normal state; conversely, a broken link indicates the EIR device is unavailable. The AMF's local link status monitoring table stores all EIR device information and their status, and can update the stored information in real time based on the EIR device status. This ensures the AMF's local link status monitoring table reflects the latest status information of all EIR devices. Based on this link status monitoring table, the target EIR's link status is determined to be valid. In the event of a link break or problem, an EIR with a normal link status can be promptly selected as the target EIR.

[0116] The method for determining a target EIR provided in this application dynamically determines the EIR device that matches the user equipment information of all EIR services obtained locally after registration with the NRF, based on different EIR deployment scenarios. Alternatively, it determines the EIR with a normal service status based on the service status of all EIRs stored locally by the AMF, and uses this EIR as the target EIR for the terminal access process to complete authentication. This method enables fast and accurate locating of the service EIR or ensures the validity of the link status, making link selection more efficient, improving the success rate of the process, and avoiding situations where the terminal access is abnormal and cannot use network services.

[0117] Optionally, the user equipment information to be authenticated is represented by a first field added to the first request message, which is used to represent the PEI corresponding to the user equipment to be authenticated.

[0118] Specifically, during the access process, the AMF sends a first request message to the NRF to determine the EIR device matching the terminal. This first request message may carry information about the user equipment to be authenticated, which can be represented in various ways, such as the terminal's IMEI or PEI. The existing flowchart of the AMF's EIR discovery process is as follows: Figure 6As shown, the first request message can be an improved version of the query request message sent during the existing AMF discovery of EIR process. Specifically, a first field is added to the query request message to represent the user equipment information to be authenticated. This first field is usually represented as a string, typically the terminal's PEI information. The specific name of the first field can be set according to requirements, and its priority is usually optional. To ensure compatibility with existing messages, the priority of this first field is usually set to optional. The specific representation is shown in Table 3 below:

[0119] Table 3

[0120] Pei String O 0..1 Optional, PEI information of the terminal

[0121] This adds definitions regarding the data type, priority, and description of the first field, based on Table 2 above. The PEI is a permanent device identifier defined for 3GPP UEs accessing a 5G system. Different PEI formats can be used for different UE types and use cases. The UE should share its PEI with the network, along with an indication of the PEI format being used. If the UE supports at least one 3GPP access technology, it is assigned a PEI in a specific format.

[0122] Optionally, if the multiple EIRs are deployed globally, the target EIR is determined based on the link state monitoring table, including:

[0123] When each of the plurality of EIRs establishes a connection with each of the central points, the link status monitoring table is initialized based on the IP address, port number and initial value of service status corresponding to each of the plurality of EIRs.

[0124] The link status monitoring table is updated based on the feedback messages from the received periodic probe messages;

[0125] Based on the updated link status monitoring table, the EIR that can establish a valid link with any of the multiple EIRs is identified as the target EIR.

[0126] Specifically, in the case of global point deployment of the above-mentioned EIR, that is, when each of the multiple EIRs establishes a connection with each centralized point, the link status monitoring table is initialized based on the initial values ​​of the IP address, port number and service status corresponding to each EIR.

[0127] The initial value of the service status indicates that the EIR is currently unavailable, and the value can be set according to the specific meaning of the representation. For example, the service status can be normal, pending connection, connected, disconnected, unavailable, and abnormal, etc., with each service status corresponding to a different status value.

[0128] For the link status between the AMF and EIR, the AMF can periodically send probe messages to the EIR device. Based on the feedback messages sent by the EIR, the normality of the link between the two can be determined, thereby determining the service status of the EIR and updating the AMF's local link status monitoring table. The sending period of this probe message can be set according to actual needs, either in seconds or minutes. Furthermore, to enhance the effective acquisition of link status and ensure the success rate of upper-layer signaling, an "abnormal" or "pending determination" status is set in the service status to indicate the temporary state of the link. For example, if the feedback message corresponding to the probe message indicates that the link is not working, the service status is set to "abnormal" or "pending determination." This is because this status may be due to a temporary loss of feedback messages caused by link jitter, and does not necessarily mean that the link between the two is broken. If no corresponding feedback message is received after multiple consecutive probe messages, the service status is changed to unavailable or disconnected. The above probe messages can also use existing heartbeat messages to save network resources.

[0129] The above link status monitoring table can be represented as follows:

[0130] Primary EIR IP address Primary EIR port 0: Unavailable / 1: Normal / 2: Abnormal Alternate EIR IP address Backup EIR port 0: Unavailable / 1: Normal / 2: Abnormal

[0131] The three service states shown in the table above are only illustrative. There may be more service states for primary EIR and standby EIR, which can be set according to actual application needs.

[0132] By employing the above methods, the AMF's local link status monitoring table is updated promptly to reflect the latest service status information of the EIR devices, ensuring that the link corresponding to the selected EIR device is valid and functioning normally. In the event of an anomaly, the EIR device matching the terminal can be dynamically selected based on this link status monitoring table.

[0133] Optionally, determining the EIR that can establish a valid link with any of the plurality of EIRs, based on the updated link state monitoring table, as the target EIR, includes:

[0134] Based on the principle of prioritizing the primary EIR, the service status of the primary EIR among the multiple EIRs is determined;

[0135] If the service status of the primary EIR is normal, then the primary EIR is determined to be the target EIR;

[0136] If the service status of the primary EIR is abnormal, the target EIR is determined based on the service status of the backup EIR among the multiple EIRs.

[0137] If the service status of the primary EIR is unavailable, then the target EIR is determined based on the service status of the backup EIR among the multiple EIRs;

[0138] The plurality of EIRs includes a primary EIR and a backup EIR.

[0139] Specifically, when multiple EIRs are deployed globally, these multiple EIRs may include one primary EIR and multiple backup EIRs, or a primary EIR and backup EIRs in pairs. The following description mainly uses the form of primary EIR and backup EIR pairs, but it is not intended to limit the specific implementation method of global point deployment of EIRs in this application.

[0140] During the EIR discovery process, AMF prioritizes the primary EIR. It first checks the status of the primary EIR and, based on its service status, determines either the primary or backup EIR as the target EIR for the terminal's access process, performing relevant verifications. Specific implementation methods include:

[0141] Determine the service status of the primary EIR, which includes normal, abnormal, and unavailable.

[0142] If the service status of the primary EIR is normal, it means that the link between the primary EIR and the AMF is in a normal state, that is, the link between the primary EIR and the AMF can communicate normally, and then the primary EIR is determined to be the target EIR.

[0143] If the primary EIR's service status is abnormal, it indicates that the link status between the primary EIR and the AMF is uncertain, representing a temporary state. It could actually be disconnected (unavailable) or functioning normally. Because there might be misjudgments due to temporary loss of feedback messages, the service status of the backup EIR should be checked first. If the backup EIR's service status is normal, it should be selected as the target EIR. If there are N EIRs that can serve as the target EIR, one of them can be randomly selected as the final target EIR. N is a positive integer greater than or equal to 2. Of course, it's also possible that all backup EIRs are abnormal or unavailable. In this case, it's necessary to revert to using the primary EIR, as there might be misjudgments regarding the link status between the primary EIR and the AMF.

[0144] If the service status of the primary EIR is unavailable, it means that the link between the primary EIR and the AMF is disconnected. Then, the service status of the backup EIR is determined, and the target EIR is determined based on the service status of the backup EIR.

[0145] Optionally, if the service status of the primary EIR is unavailable, the service status of the backup EIR among the plurality of EIRs is determined;

[0146] If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR;

[0147] If the service status of the backup EIR is abnormal, then the backup EIR is determined to be the target EIR;

[0148] If the service status of the backup EIR is unavailable, then it is determined that there is no target EIR.

[0149] Specifically, the service status of the backup EIR among multiple EIRs is determined. If the service status of the backup EIR is normal, it means that the link status between the backup EIR and the AMF is normal. Then, the backup EIR is used as the target EIR. If there are multiple backup EIRs with normal service status, any one of them can be selected as the target EIR.

[0150] If the service status of the backup EIR is abnormal, it indicates that the link status between the backup EIR and AMF is abnormal (uncertain), representing a temporary state. In reality, it may be disconnected (unavailable) or normal. That is, the link between the backup EIR and AMF may be normal, but the feedback message of the probe message is temporarily lost, causing a misjudgment. Therefore, the backup EIR can be used to try. If the corresponding process fails, it may be that the link between the backup EIR and AMF is actually disconnected. If the corresponding process succeeds, then the link between the backup EIR and AMF is actually normal.

[0151] If the service status of the standby EIR is unavailable, it means that the link between the standby EIR and the AMF is disconnected. In other words, the link between the primary EIR and the standby EIR and the AMF is disconnected, so there is no target EIR.

[0152] The above diagram illustrates the overall process for determining the target EIR based on the link status monitoring table, as follows: Figure 10 As shown.

[0153] The method for determining a target EIR provided in this application dynamically determines the EIR device that matches the user equipment information of all EIR services obtained locally after registration with the NRF, based on different EIR deployment scenarios. Alternatively, it determines the EIR with a normal service status based on the service status of all EIRs stored locally by the AMF, and uses this EIR as the target EIR for the terminal access process to complete authentication. This method enables fast and accurate locating of the service EIR or ensures the validity of the link status, making link selection more efficient, improving the success rate of the process, and avoiding situations where the terminal access is abnormal and cannot use network services.

[0154] Figure 11This is a second schematic flowchart of the method for determining the target EIR provided in the embodiments of this application, as shown below. Figure 11 As shown, this method is applied to EIR and includes:

[0155] Step 1101: When the EIR is deployed at a central point, the EIR sends a registration message to the NRF, the registration message including first information for representing user equipment information of the EIR service;

[0156] Step 1102: When the EIR is deployed globally, based on the probe messages periodically sent by the AMF, the EIR sends a feedback message, which includes the EIR's IP address, port number and service status, and is used to update the AMF's link status monitoring table.

[0157] Specifically, EIRs can be deployed at centralized points or globally. In different deployment scenarios, to facilitate the AMF's accurate identification of the target EIR, the EIR device needs to report the user equipment information of its services when registering with the NRF. The NRF receives all the user equipment information sent during EIR registration and stores it locally. Based on the user equipment information to be authenticated carried in the first request message sent by the AMF, the NRF finds the matching EIR device in the user equipment information of all EIR services stored locally, and uses it as the target EIR.

[0158] Alternatively, the AMF can configure a link status monitoring table locally, and the AMF can periodically send probe messages to the EIR. The EIR can then send feedback messages to the AMF based on the real-time status, which are used by the AMF to update the link status monitoring table. The feedback messages sent by the EIR include the EIR's device information and corresponding status information. The EIR's device information can be represented by the EIR's IP address or by the EIR's IP address and port number. The status information corresponding to the EIR device can be the service status of the EIR device, indicating the status of the link between the EIR device and the AMF device.

[0159] The method for determining a target EIR provided in this application dynamically determines the EIR device that matches the user equipment information of all EIR services obtained locally after registration with the NRF, based on different EIR deployment scenarios. Alternatively, it determines the EIR with a normal service status based on the service status of all EIRs stored locally by the AMF, and uses this EIR as the target EIR for the terminal access process to complete authentication. This method enables fast and accurate locating of the service EIR or ensures the validity of the link status, making link selection more efficient, improving the success rate of the process, and avoiding situations where the terminal access is abnormal and cannot use network services.

[0160] Optionally, if the EIR is deployed at a centralized point, and the user equipment information of the EIR service changes, the EIR sends the updated first information to the NRF.

[0161] Specifically, when the EIR is deployed at a centralized point, if the user equipment information of the EIR service changes, such as adding new user equipment information, deleting one or more user equipment information, or changing the device identifier or the corresponding IP address of one or more user equipment information, the EIR can send the updated first information representing the user equipment information of the EIR service to the NRF.

[0162] Therefore, even when EIR is deployed at a centralized point, the user equipment information of all EIR services stored by NRF can still be updated in a timely manner.

[0163] Optionally, the first information is represented by a second field added to the registration message. The second field is used to define the range of the user equipment's PEI, including the start point of the PEI value, the end point of the PEI value, and the pattern rules of the PEI value.

[0164] Specifically, during the registration process with the NRF, the registration message sent by the EIR is an improvement on the original registration message. It adds first information to represent user equipment information for EIR services. The improvement is achieved by adding a second field to the original registration message. This second field is used to define the range of PEI corresponding to the user equipment, including the start point of the PEI value, the end point of the PEI value, and the pattern rules of the PEI value.

[0165] The starting point, ending point, and pattern rules of PEI values ​​are typically represented as strings in the message body using regular expressions.

[0166] The second field added to the registration message can be represented as follows:

[0167] 5geirinfo 5geirInfo O 0..1 5GEIR-specific information

[0168] The attribute corresponding to this second field can be expanded into a hierarchical structure. Specifically, the definition of 5geirInfo is as follows:

[0169] peiRanges array(peiRange) C 1..N PEI range

[0170] The definition of peiRange is as follows: the starting point of PEI value corresponds to the attribute name start, the ending point of PEI value corresponds to the attribute name end, and the pattern rule of PEI value corresponds to the attribute name pattern.

[0171]

[0172] In this context, the attribute names `start` and `end`, as well as `start` and `pattern`, are combined to determine the range of the PEI. That is, the range of the corresponding PEI is determined based on the starting and ending points of the PEI values, or based on the starting point and the pattern rules of the PEI values. Regular expressions, also known as definite expressions, are text patterns that include ordinary characters (e.g., letters from a to z) and special characters (called "metacharacters"), and are a concept in computer science. Regular expressions use a single string to describe and match a series of strings that match a certain syntax rule. They are commonly used to search for and replace text that conforms to a certain pattern (rule). In other words, regular expressions limit the corresponding rules that the PEI values ​​must satisfy.

[0173] The method for determining a target EIR provided in this application dynamically determines the EIR device that matches the user equipment information of all EIR services obtained locally after registration with the NRF, based on different EIR deployment scenarios. Alternatively, it determines the EIR with a normal service status based on the service status of all EIRs stored locally by the AMF, and uses this EIR as the target EIR for the terminal access process to complete authentication. This method enables fast and accurate locating of the service EIR or ensures the validity of the link status, making link selection more efficient, improving the success rate of the process, and avoiding situations where the terminal access is abnormal and cannot use network services.

[0174] Figure 12 This is the third flowchart illustrating the method for determining the target EIR provided in the embodiments of this application, as shown below. Figure 12 As shown, this method is applied to NRF and specifically includes:

[0175] Step 1201: Based on the first request message sent by the AMF and the first set, determine the first response message corresponding to the first request message; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated;

[0176] The first set includes user equipment information for each EIR service in multiple EIRs.

[0177] Specifically, when the EIR is deployed at a centralized point, the NRF receives a first request message from the AMF. This first request message carries information about the user equipment to be authenticated, and combines this information with a first set stored locally by the NRF. This first set includes information about all EIR devices and information about all user equipment served by that EIR device. Based on the user equipment to be authenticated information carried in the first request message, the NRF filters the EIR devices in the first set that match the user equipment to be authenticated information, and selects them as target EIR devices to assist the terminal device in completing the verification process.

[0178] The method for determining a target EIR provided in this application dynamically determines the EIR device that matches the user equipment information of all EIR services obtained locally after registration with the NRF, based on different EIR deployment scenarios. Alternatively, it determines the EIR with a normal service status based on the service status of all EIRs stored locally by the AMF, and uses this EIR as the target EIR for the terminal access process to complete authentication. This method enables fast and accurate locating of the service EIR or ensures the validity of the link status, making link selection more efficient, improving the success rate of the process, and avoiding situations where the terminal access is abnormal and cannot use network services.

[0179] Optionally, the method for determining the first set includes:

[0180] In the case where the multiple EIRs are deployed at a centralized point, a first set is determined based on the registration messages sent by each of the multiple EIRs; the registration messages include first information for representing user equipment information of the EIR service; the first set is composed of the first information included in the registration messages sent by all the EIRs.

[0181] Specifically, when the EIR device is deployed at a centralized point, after the 5G-EIR device is started, it sends a registration message to the NRF. The registration message adds first information to indicate the user equipment information served (managed) by the EIR device. The first information can be represented as the PEI range, specifically including the start point of the PEI value, the end point of the PEI value, and the pattern rules of the PEI value.

[0182] After the NRF receives the registration messages sent by all EIR devices, the information of all EIR devices and the user equipment served by the EIR devices constitutes the first set.

[0183] Figure 13 This is a schematic diagram of an AMF structure provided in an embodiment of this application, as shown below. Figure 13As shown, the Access and Mobility Management Function (AMF) includes a memory 1320, a transceiver 1310, and a processor 1300; wherein the processor 1300 and the memory 1320 can also be physically arranged separately.

[0184] The memory 1320 is used to store computer programs; the transceiver 1310 is used to send and receive data under the control of the processor 1300.

[0185] Specifically, transceiver 1310 is used to receive and send data under the control of processor 1300.

[0186] Among them, Figure 13 In this application, the bus architecture may include any number of interconnected buses and bridges, specifically linking various circuits of one or more processors represented by processor 1300 and memory represented by memory 1320 together. The bus architecture may also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be further described herein. The bus interface provides an interface. The transceiver 1310 may be multiple elements, including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium, including wireless channels, wired channels, optical fibers, and other transmission media.

[0187] The processor 1300 is responsible for managing the bus architecture and general processing, while the memory 1320 can store the data used by the processor 1300 when performing operations.

[0188] The processor 1300 can be a central processing unit (CPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor can also adopt a multi-core architecture.

[0189] The processor 1300 executes any of the methods described in the embodiments of this application according to the obtained executable instructions by calling the computer program stored in the memory 1320, for example:

[0190] Based on the status of multiple EIR deployments, it is determined whether the multiple EIRs are centrally deployed or globally deployed;

[0191] If the multiple EIRs are deployed at a centralized point, a first request message is sent to the NRF to determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the multiple EIRs.

[0192] If the multiple EIRs are deployed globally, the target EIR is determined based on the link status monitoring table; the link status monitoring table includes the IP address, port number, and service status of each of the multiple EIRs. Optionally, the user equipment information to be authenticated is represented by a first field added to the first request message, which is used to represent the PEI corresponding to the user equipment to be authenticated.

[0193] Optionally, if the multiple EIRs are deployed globally, the target EIR is determined based on the link state monitoring table, including:

[0194] When each of the plurality of EIRs establishes a connection with each of the central points, the link status monitoring table is initialized based on the IP address, port number and initial value of service status corresponding to each of the plurality of EIRs.

[0195] The link status monitoring table is updated based on the feedback messages from the received periodic probe messages;

[0196] Based on the updated link status monitoring table, the EIR that can establish a valid link with any of the multiple EIRs is identified as the target EIR.

[0197] Optionally, determining the EIR that can establish a valid link with any of the plurality of EIRs, based on the updated link state monitoring table, as the target EIR, includes:

[0198] Based on the principle of prioritizing the primary EIR, the service status of the primary EIR among the multiple EIRs is determined;

[0199] If the service status of the primary EIR is normal, then the primary EIR is determined to be the target EIR;

[0200] If the service status of the primary EIR is abnormal, the target EIR is determined based on the service status of the backup EIR among the multiple EIRs.

[0201] If the service status of the primary EIR is unavailable, then the target EIR is determined based on the service status of the backup EIR among the multiple EIRs;

[0202] The plurality of EIRs includes a primary EIR and a backup EIR.

[0203] Optionally, if the service status of the primary EIR is abnormal, determining the target EIR based on the service status of the backup EIR among the plurality of EIRs includes:

[0204] If the service status of the primary EIR is abnormal, determine the service status of the backup EIR among the plurality of EIRs;

[0205] If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR;

[0206] If the service status of the backup EIR is abnormal or unavailable, then the primary EIR is determined to be the target EIR.

[0207] Optionally, if the service status of the primary EIR is unavailable, determining the target EIR based on the service status of the backup EIRs among the plurality of EIRs includes:

[0208] If the service status of the primary EIR is unavailable, determine the service status of the backup EIR among the plurality of EIRs;

[0209] If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR;

[0210] If the service status of the backup EIR is abnormal, then the backup EIR is determined to be the target EIR;

[0211] If the service status of the backup EIR is unavailable, then it is determined that there is no target EIR.

[0212] Figure 14 This is a schematic diagram of the structure of an EIR provided in an embodiment of this application, as shown below. Figure 14 As shown, the device identification register EIR includes a memory 1420, a transceiver 1410, and a processor 1400; wherein the processor 1400 and the memory 1420 can also be physically arranged separately.

[0213] The memory 1420 is used to store computer programs; the transceiver 1410 is used to send and receive data under the control of the processor 1400.

[0214] Specifically, transceiver 1410 is used to receive and send data under the control of processor 1400.

[0215] Among them, Figure 14In this application, the bus architecture may include any number of interconnected buses and bridges, specifically linking various circuits of one or more processors represented by processor 1400 and memory represented by memory 1420 together. The bus architecture may also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be further described herein. The bus interface provides an interface. The transceiver 1410 may be multiple elements, including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium, including wireless channels, wired channels, optical fibers, and other transmission media.

[0216] The processor 1400 is responsible for managing the bus architecture and general processing, while the memory 1420 can store the data used by the processor 1400 when performing operations.

[0217] The processor 1400 can be a CPU, ASIC, FPGA or CPLD, and the processor can also adopt a multi-core architecture.

[0218] The processor 1400 executes any of the methods described in the embodiments of this application according to the obtained executable instructions by calling the computer program stored in the memory 1420. For example:

[0219] When the EIR is deployed at a centralized point, the EIR sends a registration message to the NRF, and the registration message includes first information for representing user equipment information of the EIR service;

[0220] When the EIR is deployed globally, based on the probe messages periodically sent by the AMF, the EIR sends a feedback message, which includes the EIR's IP address, port number, and service status, and is used to update the AMF's link state monitoring table.

[0221] Optionally, the method further includes:

[0222] If the EIR is deployed at a centralized point, and the user equipment information of the EIR service changes, the EIR sends the updated first information to the NRF.

[0223] Optionally, the first information is represented by a second field added to the registration message. The second field is used to define the range of the user equipment's PEI, including the starting point of the PEI value, the ending point of the PEI value, and the pattern rules of the PEI value.

[0224] Optionally, the starting point, ending point, and pattern rules of the PEI value are all represented by regular expressions.

[0225] Figure 15 This is a schematic diagram of an NRF structure provided in an embodiment of this application, as shown below. Figure 15 As shown, the network storage function (NRF) includes a memory 1520, a transceiver 1510, and a processor 1500; wherein the processor 1500 and the memory 1520 can also be physically arranged separately.

[0226] The memory 1520 is used to store computer programs; the transceiver 1510 is used to send and receive data under the control of the processor 1500.

[0227] Specifically, transceiver 1510 is used to receive and send data under the control of processor 1500.

[0228] Among them, Figure 15 In this application, the bus architecture may include any number of interconnected buses and bridges, specifically linking various circuits of one or more processors represented by processor 1500 and memory represented by memory 1520 together. The bus architecture may also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be further described herein. The bus interface provides an interface. The transceiver 1510 may be multiple elements, including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium, including wireless channels, wired channels, optical fibers, and other transmission media.

[0229] The processor 1500 is responsible for managing the bus architecture and general processing, while the memory 1520 can store the data used by the processor 1500 when performing operations.

[0230] The processor 1500 can be a CPU, ASIC, FPGA or CPLD, and the processor can also adopt a multi-core architecture.

[0231] The processor 1500 executes any of the methods described in the embodiments of this application according to the obtained executable instructions by calling the computer program stored in the memory 1520. For example:

[0232] Based on the first request message sent by the AMF and the first set, a first response message corresponding to the first request message is determined; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated;

[0233] The first set includes user equipment information for each EIR service in multiple EIRs.

[0234] Optionally, the method for determining the first set includes:

[0235] In the case where the multiple EIRs are deployed at a centralized point, a first set is determined based on the registration messages sent by each of the multiple EIRs; the registration messages include first information for representing user equipment information of the EIR service; the first set is composed of the first information included in the registration messages sent by all the EIRs.

[0236] It should be noted that the electronic device provided in this application embodiment can implement all the method steps implemented in the above method embodiment and can achieve the same technical effect. Here, the parts and beneficial effects that are the same as those in the method embodiment will not be described in detail.

[0237] Figure 16 This is one of the structural schematic diagrams of a device for determining a target EIR provided in an embodiment of this application. This device is applied to an AMF, such as... Figure 16 As shown, the device includes:

[0238] The first determining module 1600 is used to determine whether the multiple EIRs are centrally deployed or globally deployed based on the status of the multiple EIRs deployments.

[0239] The central point module 1610 is used to send a first request message to the NRF if the plurality of EIRs are deployed at a central point, so that the NRF can determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the plurality of EIRs.

[0240] The global point module 1620 is used to determine the target EIR based on the link status monitoring table if the multiple EIRs are deployed as global points; the link status monitoring table includes the IP address, port number and service status of each of the multiple EIRs.

[0241] Optionally, the user equipment information to be authenticated is represented by a first field added to the first request message, which is used to represent the PEI corresponding to the user equipment to be authenticated.

[0242] Optionally, the global point module 1620 is also used for:

[0243] When each of the plurality of EIRs establishes a connection with each of the central points, the link status monitoring table is initialized based on the IP address, port number and initial value of service status corresponding to each of the plurality of EIRs.

[0244] The link status monitoring table is updated based on the feedback messages from the received periodic probe messages;

[0245] Based on the updated link status monitoring table, the EIR that can establish a valid link with any of the multiple EIRs is identified as the target EIR.

[0246] Optionally, in the process of determining, based on the updated link state monitoring table, the global point module 1620 identifies the EIR that can establish a valid link with any of the plurality of EIRs as the target EIR, specifically for:

[0247] Based on the principle of prioritizing the primary EIR, the service status of the primary EIR among the multiple EIRs is determined;

[0248] If the service status of the primary EIR is normal, then the primary EIR is determined to be the target EIR;

[0249] If the service status of the primary EIR is abnormal, the target EIR is determined based on the service status of the backup EIR among the multiple EIRs.

[0250] If the service status of the primary EIR is unavailable, then the target EIR is determined based on the service status of the backup EIR among the multiple EIRs;

[0251] The plurality of EIRs includes a primary EIR and a backup EIR.

[0252] Optionally, the global point module 1620 is also used for:

[0253] If the service status of the primary EIR is abnormal, determine the service status of the backup EIR among the plurality of EIRs;

[0254] If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR;

[0255] If the service status of the backup EIR is abnormal or unavailable, then the primary EIR is determined to be the target EIR.

[0256] Optionally, the global point module 1620 is also used for:

[0257] If the service status of the primary EIR is unavailable, determine the service status of the backup EIR among the plurality of EIRs;

[0258] If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR;

[0259] If the service status of the backup EIR is abnormal, then the backup EIR is determined to be the target EIR;

[0260] If the service status of the backup EIR is unavailable, then it is determined that there is no target EIR.

[0261] Figure 17 This is a second schematic diagram of the device for determining a target EIR provided in the embodiments of this application. This device is applied to EIR, such as... Figure 17 As shown, the device includes:

[0262] The first sending module 1700 is configured to, when the EIR is deployed as a centralized point, send a registration message to the NRF, wherein the registration message includes first information representing user equipment information of the EIR service;

[0263] The second sending module 1710 is used to send a feedback message to the EIR based on the probe messages periodically sent by the AMF when the EIR is deployed as a global point. The feedback message includes the IP address, port number and service status of the EIR, and is used to update the link status monitoring table of the AMF.

[0264] Optionally, the first sending module 1700 shown is further configured to, if the user equipment information of the EIR service changes when the EIR is deployed at a centralized point, send the updated first information to the NRF.

[0265] Optionally, the first information is represented by a second field added to the registration message. The second field is used to define the range of the user equipment's PEI, including the starting point of the PEI value, the ending point of the PEI value, and the pattern rules of the PEI value.

[0266] Optionally, the starting point, ending point, and pattern rules of the PEI value are all represented by regular expressions.

[0267] Figure 18 This is the third schematic diagram of the device for determining a target EIR provided in the embodiments of this application. This device is applied to NRF, such as... Figure 18 As shown, the device includes:

[0268] The second determining module 1800 is used to determine a first response message corresponding to the first request message based on the first request message sent by the received AMF and a first set; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated;

[0269] The first set includes user equipment information for each EIR service in multiple EIRs.

[0270] Optionally, the device further includes a first collection module 1810, for:

[0271] In the case where the multiple EIRs are deployed at a centralized point, a first set is determined based on the registration messages sent by each of the multiple EIRs; the registration messages include first information for representing user equipment information of the EIR service; the first set is composed of the first information included in the registration messages sent by all the EIRs.

[0272] It should be noted that the division of units in the embodiments of this application is illustrative and only represents one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units described above can be implemented in hardware or as software functional units.

[0273] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a processor-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0274] It should be noted that the apparatus provided in this application embodiment can implement all the method steps implemented in the above method embodiment and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.

[0275] On the other hand, embodiments of this application also provide a computer-readable storage medium storing a computer program for causing a computer to execute the methods for determining a target EIR provided in the above embodiments.

[0276] It should be noted that the computer-readable storage medium provided in this application embodiment can implement all the method steps implemented in the above method embodiment and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.

[0277] The computer-readable storage medium can be any available medium or data storage device that a computer can access, including but not limited to magnetic storage (e.g., floppy disks, hard disks, magnetic tapes, magneto-optical disks (MOs), etc.), optical storage (e.g., CDs, DVDs, BDs, HVDs, etc.), and semiconductor storage (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND flash), solid-state drives (SSDs)).

[0278] The technical solutions provided in this application can be applied to various systems, especially 5G systems. For example, applicable systems may include Global System for Mobile Communication (GSM), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA) General Packet Radio Service (GPRS), Long Term Evolution (LTE), LTE Frequency Division Duplex (FDD), LTE Time Division Duplex (TDD), Long Term Evolution Advanced (LTE-A), Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), and 5G New Radio (NR). All of these systems include terminal equipment and network equipment. The systems may also include a core network component, such as Evolved Packet System (EPS) and 5G system (5GS).

[0279] The terminal involved in the embodiments of this application can be a device that provides voice and / or data connectivity to a user, a handheld device with wireless connectivity, or other processing devices connected to a wireless modem. The name of the terminal may differ in different systems; for example, in a 5G system, the terminal can be called a User Equipment (UE). The wireless terminal device can communicate with one or more core networks (CNs) via a Radio Access Network (RAN). The wireless terminal device can be a mobile terminal device, such as a mobile phone (or "cellular" phone) and a computer with a mobile terminal device, for example, a portable, pocket-sized, handheld, computer-embedded, or vehicle-mounted mobile device. They exchange voice and / or data with the radio access network. Examples include Personal Communication Service (PCS) phones, cordless phones, Session Initiated Protocol (SIP) phones, Wireless Local Loop (WLL) stations, and Personal Digital Assistants (PDAs). Wireless terminal equipment can also be referred to as a system, subscriber unit, subscriber station, mobile station, mobile station, remote station, access point, remote terminal, access terminal, user terminal, user agent, or user device, but is not limited to these terms in the embodiments of this application.

[0280] The network device involved in this application embodiment can be a base station, which may include multiple cells providing services to terminals. Depending on the specific application, a base station may also be called an access point, or a device in an access network that communicates with a wireless terminal device through one or more sectors on the air interface, or other names. The network device can be used to exchange received air frames with Internet Protocol (IP) packets, acting as a router between the wireless terminal device and the rest of the access network, where the rest of the access network may include an Internet Protocol (IP) communication network. The network device can also coordinate the attribute management of the air interface. For example, the network equipment involved in the embodiments of this application can be a base transceiver station (BTS) in a Global System for Mobile communications (GSM) or Code Division Multiple Access (CDMA), a NodeB in a Wide-band Code Division Multiple Access (WCDMA) system, an evolved Node B (eNB or e-NodeB) in a long term evolution (LTE) system, a 5G base station (gNB) in a next generation system, a Home evolved Node B (HeNB), a relay node, a femto, a pico, etc., and is not limited in the embodiments of this application. In some network structures, the network equipment may include centralized unit (CU) nodes and distributed unit (DU) nodes, and the centralized unit and distributed unit may be geographically separated.

[0281] Network devices and terminal devices can each use one or more antennas for multiple-input multiple-output (MIMO) transmission. MIMO transmission can be single-user MIMO (SU-MIMO) or multiple-user MIMO (MU-MIMO). Depending on the configuration and number of antenna combinations, MIMO transmission can be 2D-MIMO, 3D-MIMO, FD-MIMO, or massive-MIMO, and can also be diversity transmission, precoding transmission, or beamforming transmission, etc.

[0282] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0283] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0284] These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0285] These processors can execute instructions that can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable device for implementing the process. Figure 1One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0286] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method of determining a target EIR, characterized by, Applied to AMF, the method includes: Based on the status of multiple EIR deployments, it is determined whether the multiple EIRs are centrally deployed or globally deployed; If the multiple EIRs are deployed at a centralized point, a first request message is sent to the NRF to determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the multiple EIRs. If the multiple EIRs are deployed globally, the target EIR is determined based on the link status monitoring table; the link status monitoring table includes the IP address, port number and service status of each of the multiple EIRs.

2. The method of determining a target EIR according to claim 1, wherein, The user equipment information to be authenticated is represented by a first field added to the first request message, which is used to represent the PEI corresponding to the user equipment to be authenticated.

3. The method of determining a target EIR of claim 1, wherein, If the multiple EIRs are deployed globally, the target EIR is determined based on the link state monitoring table, including: When each of the plurality of EIRs establishes a connection with each of the central points, the link status monitoring table is initialized based on the IP address, port number and initial value of service status corresponding to each of the plurality of EIRs. The link status monitoring table is updated based on the feedback messages from the received periodic probe messages; Based on the updated link status monitoring table, the EIR that can establish a valid link with any of the multiple EIRs is identified as the target EIR.

4. The method for determining the target EIR according to claim 3, characterized in that, The step of determining the EIR that can establish a valid link with any of the plurality of EIRs, based on the updated link status monitoring table, as the target EIR includes: Based on the principle of prioritizing the primary EIR, the service status of the primary EIR among the multiple EIRs is determined; If the service status of the primary EIR is normal, then the primary EIR is determined to be the target EIR; If the service status of the primary EIR is abnormal, the target EIR is determined based on the service status of the backup EIR among the multiple EIRs. If the service status of the primary EIR is unavailable, then the target EIR is determined based on the service status of the backup EIR among the multiple EIRs; The plurality of EIRs includes a primary EIR and a backup EIR.

5. The method for determining the target EIR according to claim 4, characterized in that, If the service status of the primary EIR is abnormal, then based on the service status of the backup EIR among the multiple EIRs, the target EIR is determined, including: If the service status of the primary EIR is abnormal, determine the service status of the backup EIR among the plurality of EIRs; If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR; If the service status of the backup EIR is abnormal or unavailable, then the primary EIR is determined to be the target EIR.

6. The method for determining the target EIR according to claim 4, characterized in that, If the service status of the primary EIR is unavailable, then based on the service status of the backup EIRs among the plurality of EIRs, the target EIR is determined, including: If the service status of the primary EIR is unavailable, determine the service status of the backup EIR among the plurality of EIRs; If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR; If the service status of the backup EIR is abnormal, then the backup EIR is determined to be the target EIR; If the service status of the backup EIR is unavailable, then it is determined that there is no target EIR.

7. A method for determining a target EIR, characterized in that, Applied to EIR, the method includes: When the EIR is deployed at a centralized point, the EIR sends a registration message to the NRF. The registration message includes first information representing user equipment information of the EIR service, so that the NRF can construct a first set for matching target EIRs and complete the target EIR matching determination corresponding to the user equipment to be authenticated. When the EIR is deployed globally, based on the probe messages periodically sent by the AMF, the EIR sends a feedback message. The feedback message includes the EIR's IP address, port number, and service status, which is used to update the AMF's link state monitoring table so that the AMF can determine the target EIR based on the updated link state monitoring table.

8. The method for determining a target EIR according to claim 7, characterized in that, The method further includes: If the EIR is deployed at a centralized point, and the user equipment information of the EIR service changes, the EIR sends the updated first information to the NRF.

9. The method for determining a target EIR according to claim 7 or 8, characterized in that, The first information is represented by a second field added to the registration message. The second field is used to define the range of the user device's PEI, including the starting point of the PEI value, the ending point of the PEI value, and the pattern rules of the PEI value.

10. The method for determining a target EIR according to claim 9, characterized in that, The starting point, ending point, and pattern rules of the PEI value are all represented by regular expressions.

11. A method for determining a target EIR, characterized in that, Applied to NRF, the method includes: Based on the first request message sent by the AMF and the first set, a first response message corresponding to the first request message is determined; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated; the first response message is sent to the AMF so that the AMF can determine the target EIR; The first set includes user equipment information for each EIR service in multiple EIRs; the method for determining the first set includes: In the case where the multiple EIRs are deployed at a centralized point, a first set is determined based on the registration messages sent by each of the multiple EIRs; the registration messages include first information for representing user equipment information of the EIR service; the first set is composed of the first information included in the registration messages sent by all the EIRs.

12. An Access and Mobility Management Function (AMF) device, characterized in that, Includes memory, transceiver, and processor; Memory, used to store computer programs; Transceiver, used to send and receive data under the control of the processor; Processor, configured to read the computer program in the memory and perform the following operations: Based on the status of multiple EIR deployments, it is determined whether the multiple EIRs are centrally deployed or globally deployed; If the multiple EIRs are deployed at a centralized point, a first request message is sent to the NRF to determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the multiple EIRs. If the multiple EIRs are deployed globally, the target EIR is determined based on the link status monitoring table; the link status monitoring table includes the IP address, port number and service status of each of the multiple EIRs.

13. The AMF device according to claim 12, characterized in that, The user equipment information to be authenticated is represented by a first field added to the first request message, which is used to represent the PEI corresponding to the user equipment to be authenticated.

14. The AMF device according to claim 12, characterized in that, If the multiple EIRs are deployed globally, the target EIR is determined based on the link state monitoring table, including: When each of the plurality of EIRs establishes a connection with each of the central points, the link status monitoring table is initialized based on the IP address, port number and initial value of service status corresponding to each of the plurality of EIRs. The link status monitoring table is updated based on the feedback messages from the received periodic probe messages; Based on the updated link status monitoring table, the EIR that can establish a valid link with any of the multiple EIRs is identified as the target EIR.

15. The AMF device according to claim 14, characterized in that, The step of determining the EIR that can establish a valid link with any of the plurality of EIRs, based on the updated link status monitoring table, as the target EIR includes: Based on the principle of prioritizing the primary EIR, the service status of the primary EIR among the multiple EIRs is determined; If the service status of the primary EIR is normal, then the primary EIR is determined to be the target EIR; If the service status of the primary EIR is abnormal, the target EIR is determined based on the service status of the backup EIR among the multiple EIRs. If the service status of the primary EIR is unavailable, then the target EIR is determined based on the service status of the backup EIR among the multiple EIRs; The plurality of EIRs includes a primary EIR and a backup EIR.

16. The AMF device according to claim 15, characterized in that, If the service status of the primary EIR is abnormal, then based on the service status of the backup EIR among the multiple EIRs, the target EIR is determined, including: If the service status of the primary EIR is abnormal, determine the service status of the backup EIR among the plurality of EIRs; If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR; If the service status of the backup EIR is abnormal or unavailable, then the primary EIR is determined to be the target EIR.

17. The AMF device according to claim 15, characterized in that, If the service status of the primary EIR is unavailable, then based on the service status of the backup EIRs among the plurality of EIRs, the target EIR is determined, including: If the service status of the primary EIR is unavailable, determine the service status of the backup EIR among the plurality of EIRs; If the service status of the backup EIR is normal, then the backup EIR is determined to be the target EIR; If the service status of the backup EIR is abnormal, then the backup EIR is determined to be the target EIR; If the service status of the backup EIR is unavailable, then it is determined that there is no target EIR.

18. A Device Identification Register (EIR) device, characterized in that, Includes memory, transceiver, and processor; The memory is used to store computer programs; the transceiver is used to send and receive data under the control of the processor. Processor, configured to read the computer program in the memory and perform the following operations: When the EIR is deployed at a centralized point, the EIR sends a registration message to the NRF. The registration message includes first information representing user equipment information of the EIR service, so that the NRF can construct a first set for matching target EIRs and complete the target EIR matching determination corresponding to the user equipment to be authenticated. When the EIR is deployed globally, based on the probe messages periodically sent by the AMF, the EIR sends a feedback message. The feedback message includes the EIR's IP address, port number, and service status, which is used to update the AMF's link state monitoring table so that the AMF can determine the target EIR based on the updated link state monitoring table.

19. The EIR device according to claim 18, characterized in that, The operation also includes: If the EIR is deployed at a centralized point, and the user equipment information of the EIR service changes, the EIR sends the updated first information to the NRF.

20. The EIR device according to claim 18 or 19, characterized in that, The first information is represented by a second field added to the registration message. The second field is used to define the range of the user device's PEI, including the starting point of the PEI value, the ending point of the PEI value, and the pattern rules of the PEI value.

21. The EIR device according to claim 20, characterized in that, The starting point, ending point, and pattern rules of the PEI value are all represented by regular expressions.

22. A network storage function (NRF) device, characterized in that, Includes memory, transceiver, and processor; Memory, used to store computer programs; The transceiver is used to send and receive data under the control of the processor; the processor is used to read the computer program in the memory and perform the following operations: Based on the first request message sent by the AMF and the first set, a first response message corresponding to the first request message is determined; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated; the first response message is sent to the AMF so that the AMF can determine the target EIR; The first set includes user equipment information for each EIR service in multiple EIRs; the method for determining the first set includes: In the case where the multiple EIRs are deployed at a centralized point, a first set is determined based on the registration messages sent by each of the multiple EIRs; the registration messages include first information for representing user equipment information of the EIR service; the first set is composed of the first information included in the registration messages sent by all the EIRs.

23. An apparatus for determining a target EIR, characterized in that, Applied to AMF, including: The first determining module is used to determine whether the multiple EIRs are centrally deployed or globally deployed based on the status of the multiple EIRs. The centralization module is used to send a first request message to the NRF if the multiple EIRs are deployed at a centralization point, so that the NRF can determine the target EIR that matches the user equipment information to be authenticated carried in the first request message; the NRF locally stores the user equipment information served by each of the multiple EIRs. The global point module is used to determine the target EIR based on the link status monitoring table if the multiple EIRs are deployed as global points; the link status monitoring table includes the IP address, port number and service status of each of the multiple EIRs.

24. An apparatus for determining a target EIR, characterized in that, Applied to EIR, including: The first sending module is configured to, when the EIR is deployed at a centralized point, send a registration message to the NRF, wherein the registration message includes first information representing user equipment information of the EIR service, so that the NRF can construct a first set for matching target EIRs and complete the target EIR matching determination corresponding to the user equipment to be authenticated; The second sending module is used to, when the EIR is deployed as a global point, send a feedback message to the EIR based on the probe messages periodically sent by the AMF. The feedback message includes the IP address, port number and service status of the EIR, and is used to update the AMF's link state monitoring table so that the AMF can determine the target EIR based on the updated link state monitoring table.

25. An apparatus for determining a target EIR, characterized in that, Applied to NRF, including: The second determining module is used to determine a first response message corresponding to the first request message based on the first request message sent by the received AMF and a first set; the first request message carries user equipment information to be authenticated, and the first response message includes a target EIR that matches the user equipment information to be authenticated; the first response message is sent to the AMF so that the AMF determines the target EIR; The first set includes user equipment information for each EIR service in multiple EIRs; the method for determining the first set includes: In the case where the multiple EIRs are deployed at a centralized point, a first set is determined based on the registration messages sent by each of the multiple EIRs; the registration messages include first information for representing user equipment information of the EIR service; the first set is composed of the first information included in the registration messages sent by all the EIRs.

26. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that causes a computer to perform the method according to any one of claims 1 to 6, or the method according to any one of claims 7 to 10, or the method according to any one of claims 11 to 12.

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