CN115915093B - A method for setting an EPLMN list, core network equipment and medium - Google Patents

Abstract

The invention provides a setting method of an EPLMN list, core network equipment and a medium, wherein the method comprises the following steps: acquiring capability information of a terminal and capability information of a visiting network; judging whether the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent according to the capability information of the terminal and the capability information of the visiting network; if the terminal satisfies the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent, the roaming PLMN of the visiting network or the home PLMN of the home network is carried in the EPLMN list and is sent to the terminal, the method, the core network equipment and the medium can solve the problem that the traditional setting method of the EPLMN list cannot set the capability information of the terminal and the visiting network in a distinguishing way, voice service cannot be used after the terminal moves to the visiting network easily, or when voice service cannot be used under the visiting network by the terminal, the situation that the home network cannot be actively returned is solved, and user experience is seriously influenced.

Description

A method for setting an EPLMN list, core network equipment and medium

Technical Field

The present invention relates to the field of network technology, and in particular to a method for setting an EPLMN list, a core network device and a medium.

Background technique

5G core network roaming means that in the independent networking (SA) mode, 5G users of the home network use 5G services by accessing the 5G network of the visited network within the 5G roaming area.

However, in the 5G core network roaming scenario, since the existing EPLMN list setting method cannot differentiate the capability information of the terminal and the visited network, it is easy for the terminal to be unable to use voice services after moving to the visited network, or when the terminal cannot use voice services in the visited network, it cannot actively return to the home network, which seriously affects the user experience.

Summary of the invention

The technical problem to be solved by the present invention is to provide a method for setting an EPLMN list, a core network device and a medium in view of the above-mentioned deficiencies in the prior art, so as to solve the problem that the existing method for setting an EPLMN list cannot differentiate and issue the EPLMN list according to the capability information of the terminal and the visited network, which may easily lead to the terminal being unable to use voice services after moving to the visited network, or when the terminal is unable to use voice services in the visited network, it is unable to actively return to the home network, which seriously affects the user experience.

In a first aspect, the present invention provides a method for setting an EPLMN list, which is applied to a core network device, and the method includes:

Obtaining terminal capability information and access network capability information;

determining, according to the capability information of the terminal and the capability information of the visited network, whether the terminal satisfies a condition for setting a roaming PLMN of the visited network and a home PLMN of the home network to be equivalent;

If the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent, the roaming PLMN of the visited network or the home PLMN of the home network is carried in the EPLMN list and sent to the terminal.

Furthermore, before acquiring the capability information of the terminal, the method further includes:

receiving an attach request/registration request from the terminal, and acquiring registration information of the terminal from the attach request/registration request from the terminal;

Determining whether the terminal meets the core network roaming condition according to the registration information;

The acquiring of the capability information of the terminal and the capability information of the visited network specifically includes:

If the terminal meets the core network roaming condition, capability information of the terminal and capability information of the visited network are obtained.

Further, the registration information includes: location information of the terminal, and/or international mobile subscriber identity code IMSI, and/or international mobile equipment identity code IMEI, and/or international mobile subscriber integrated services digital network MSISDN;

The determining, according to the registration information, whether the terminal meets the core network roaming condition specifically includes:

Whether the terminal meets the core network roaming condition is determined according to the location information, and/or IMSI, and/or IMEI, and/or MSISDN of the terminal.

Further, the acquiring the capability information of the terminal specifically includes:

The new voice over air (VoNR) capability and/or evolved packet circuit fallback (EPS) FB capability of the terminal are obtained.

Further, obtaining the VoNR capability of the terminal specifically includes:

Sending a first request message to a wireless network device, where the first request message is used to request to obtain the VoNR capability of the terminal;

Receiving a first response message sent by the wireless network device based on the first request message, where the first response message carries a VoNR capability field;

The VoNR capability of the terminal is obtained according to the value of the VoNR capability field, wherein if the value of the VoNR capability field is supported, it indicates that the terminal has the VoNR capability and is in an on state; if the value of the VoNR capability field is not supported, it indicates that the terminal does not have the VoNR capability or has the VoNR capability but the VoNR capability is in a off state.

Further, the sending a first request message to the wireless network device specifically includes:

Sending a user terminal device UE wireless capability matching request message or a UE wireless capability check request message to the wireless network device;

The receiving a first response message sent by the wireless network device based on the first request message specifically includes:

receiving a UE wireless capability matching response message sent by the wireless network device based on the UE wireless capability matching request message; or,

A UE radio capability check response message is received, which is sent by the wireless network device based on the UE radio capability check request message.

Further, obtaining the VoNR capability of the terminal specifically includes:

Receiving a UE wireless capability information indication message sent by a wireless network device;

The UE radio capability information indication message is parsed to obtain the VoNR capability of the terminal.

Further, judging whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent according to the capability information of the terminal and the capability information of the visited network, specifically includes:

According to the VoNR capability and/or EPS FB capability of the terminal and the VoNR capability and EPS FB capability of the visited network, it is determined whether the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

Further, judging whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent according to the VoNR capability and/or EPS FB capability of the terminal and the VoNR capability and EPS FB capability of the visited network, specifically includes at least one of the following:

If the visited network supports the VoNR capability and the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPSFB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability and the EPS FB capability, the terminal does not support the VoNR capability and the EPSFB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal supports the VoNR capability, determining that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal does not support the VoNR capability but supports the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the EPS FB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the VoNR capability but does not support the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability and does not support the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support VoNR capability and EPS FB capability, the terminal does not support VoNR capability and EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the conditions for setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

Further, obtaining the VoNR capability of the terminal specifically includes:

receiving a tracking area update message or a mobile registration update message sent by a terminal, where the tracking area update message or the mobile registration update message carries the VoNR capability of the terminal;

The VoNR capability of the terminal is obtained from the tracking area update message or the mobile registration update message.

Further, carrying the roaming PLMN of the visited network or the home PLMN of the home network in the EPLMN list and sending it to the terminal specifically includes:

If the core network device is a home network core network device, the roaming PLMN of the visited network is carried in the EPLMN list and sent to the terminal;

If the core network device is a visited network core network device, the home PLMN of the home network is carried in the EPLMN list and sent to the terminal.

Further, carrying the roaming PLMN of the visited network or the home PLMN of the home network in the EPLMN list and sending it to the terminal specifically includes:

Sending an EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network to the terminal through an attach accept message/registration accept message; or,

An EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network is sent to the terminal through a tracking area update accept message/mobile registration update accept message.

Furthermore, the method further comprises:

If the core network device is a home network core network device and the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, the EPLMN list is not sent to the terminal, or the EPLMN list without the roaming PLMN of the visited network is sent to the terminal.

Furthermore, the method further comprises:

If the core network device is a visited network core network device and the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, the terminal access is denied, and an attachment failure message/registration failure message carrying a rejection reason value is sent to the terminal, or a tracking area update failure message/mobile registration update failure message carrying a rejection reason value is sent to the terminal.

In a second aspect, the present invention provides a core network device, including:

A capability acquisition module is used to obtain the capability information of the terminal and the capability information of the visited network;

a condition judgment module, connected to the capability acquisition module, for judging whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, according to the capability information of the terminal and the capability information of the visited network;

The list sending processing module is connected to the condition judgment module and is used to carry the roaming PLMN of the visited network or the home PLMN of the home network in the EPLMN list and send it to the terminal if the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent.

In a third aspect, the present invention provides a core network device, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to implement the method for setting the EPLMN list described in the first aspect above.

In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the method for setting the EPLMN list described in the first aspect above is implemented.

The method for setting the EPLMN list, the core network device and the medium provided by the present invention first obtain the capability information of the terminal and the capability information of the visited network; then, according to the capability information of the terminal and the capability information of the visited network, determine whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent; if the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, then the roaming PLMN of the visited network or the home PLMN of the home network is carried in the EPLMN list and sent to the terminal. Since the present invention can issue the EPLMN list in a differentiated manner according to the capability information of the terminal and the visited network, it can ensure that when the terminal cannot use the voice service of the visited network, it does not roam to the visited network through reselection or redirection, and can reduce the frequent network selection operations of the terminal, or can ensure that when the terminal cannot use the voice service in the visited network, it can actively return to the home network, thereby solving the problem that the existing method for setting the EPLMN list cannot set it in a differentiated manner according to the capability information of the terminal and the visited network, which easily leads to the situation that the terminal cannot use the voice service after moving to the visited network, or when the terminal cannot use the voice service in the visited network, it cannot actively return to the home network, which seriously affects the user experience.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a core network roaming architecture in a scenario with a home network signal according to an embodiment of the present invention;

FIG2 is a flow chart of a method for setting an EPLMN list according to Embodiment 1 of the present invention;

FIG3 is a schematic diagram of the structure of a core network device according to Embodiment 2 of the present invention;

FIG4 is a schematic diagram of the structure of a core network device according to Embodiment 3 of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the present invention, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

It should be understood that the specific embodiments and drawings described herein are only used to explain the present invention rather than to limit the present invention.

It can be understood that, in the absence of conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other.

It can be understood that, for the convenience of description, the drawings of the present invention only show the parts related to the present invention, while the parts irrelevant to the present invention are not shown in the drawings.

It can be understood that each unit and module involved in the embodiments of the present invention may correspond to only one physical structure, or may be composed of multiple physical structures, or multiple units and modules may be integrated into one physical structure.

It can be understood that, in the absence of conflict, the functions and steps marked in the flowcharts and block diagrams of the present invention may occur in an order different from that marked in the drawings.

It is understood that the flowcharts and block diagrams of the present invention illustrate the possible architectures, functions, and operations of the systems, devices, equipment, and methods according to the various embodiments of the present invention. Each box in the flowchart or block diagram may represent a unit, module, program segment, or code, which contains executable instructions for implementing the specified functions. Moreover, each box or combination of boxes in the block diagram and flowchart may be implemented by a hardware-based system that implements the specified functions, or by a combination of hardware and computer instructions.

It can be understood that the units and modules involved in the embodiments of the present invention can be implemented by software or hardware. For example, the units and modules can be located in a processor.

Application Overview

In recent years, 5G technology has developed rapidly. However, the high investment cost of 5G network deployment has greatly restricted the development speed of 5G network. Therefore, 5G shared network technology has attracted more and more attention as a way to optimize network costs. 5G co-built and shared networks are divided into two network architectures: 5G access network sharing and 5G core network roaming. Among them, 5G core network roaming refers to the use of 5G services by 5G users of the home network in the 5G roaming area by accessing the 5G network of the visited network under the independent networking (SA) mode. The 5G access network and core network of both 5G core network roaming operators are independently built and managed, and users are managed independently. The mainstream 5G core network roaming is implemented by the home routing method, that is, the roaming user data returns to the home network, and the service is provided by the home network. In the network that provides 5G core network roaming, data services, voice/video services based on IMS (IP Multimedia Subsystem) and short message services based on SMS over IP should be provided to users at the same time. The operators providing 5G core network roaming services should provide corresponding services to roaming users based on the inter-network roaming agreement.

At present, according to the scenario, the network architecture of 5G core network roaming can be divided into core network roaming in the scenario of "with home network signal" and core network roaming in the scenario of "without home network signal". Among them, the core network roaming defined by 3GPP mainly refers to the international roaming scenario, that is, when there is no home network signal, the terminal can use the visited network 5G service for access. There is no N26 interface and N14 interface between the 4G/5G core network of the home network and the 5G core network of the roaming network. The N26 interface is the interface between the home network MME (Mobility Management Entity) and the roaming network AMF (Access and Mobility Management Function), and the N14 interface is the interface between the home network AMF and the roaming network AMF. However, in the 5G core network roaming scenario, since the existing EPLMN list setting method cannot differentiate the capability information of the terminal and the visited network, it is easy for the terminal to be unable to use voice services after moving to the visited network, or when the terminal cannot use voice services in the visited network, it cannot actively return to the home network, which seriously affects the user experience.

FIG1 shows a schematic diagram of the core network roaming architecture in the scenario with a home network signal. In the scenario with a home network signal, the common method for setting the EPLMN list is as follows: when a 5G terminal first accesses, it needs to attach/register to the 4G/5G core network of the home network. When the home 4G/5G network hopes that the user can enter the visited 5G network in the case of insufficient coverage, it will send an EPLMN list to the terminal, set the shared PLMN ID of the visited network to the equivalent PLMN of the current PLMN ID under the home network, and set the shared PLMN ID to a high-priority PLMN. When the terminal receives the EPLMN list, it is found that the current PLMN has a shared PLMN ID of EPLMN, and the terminal meets the reselection requirements, or the network instructs the terminal to redirect to the shared PLMN ID. The terminal can reselect or redirect to the visited 5G network. However, since the existing method for setting the EPLMN list cannot distinguish between sending the EPLMN list based on the capability information of the terminal and the visited network, it is easy to cause the terminal to be unable to use voice services after moving to the visited 5G network, which seriously affects the user experience. For example, operator A and operator B have deployed a core network roaming solution in a signal scenario. Operator B can provide VoNR (Voice Over New Radio) voice services to operators A's users, but because operator B has not opened the N26 interface between operator B and operator A, it cannot provide EPS FB services to operators A's user UEA. When UEA attaches/registers to A network, operator A's 4G/5G network sends the EPLMN list to UEA and sets PLMN A and PLMN X as equivalent PLMNs. Then, UEA can meet the requirements of reselection and redirection from operator network A to operator B's 5G network. However, there are both VoNR-supporting terminals and non-VoNR-supporting terminals in operator A's network. When the non-VoNR-supporting terminal UEA roams to operator B's 5G network, operator B's network cannot provide voice services to UEA. The terminal will use the offline re-search method to return to 4G or cannot use voice services, which greatly affects the user experience.

In the scenario of no home network signal, the common method of sending the EPLMN list is: when the 5G terminal accesses for the first time, due to the lack of home network signal, the 5G terminal randomly selects an accessible network for registration; when the network currently registered by the 5G terminal user happens to be a visited network that has signed a core network roaming contract, the visited network will send the EPLMN list to the terminal, which carries the PLMN of the home network; after the terminal receives the EPLMN list, it sets the visited network PLMN of the core network roaming and the home network PLMN to be equivalent, then the 5G terminal will not regularly search for the home network PLMN network signal as defined by the 3GPP protocol, and try to actively return to the home network cell. However, when the 5G terminal is turned on for the first time, or when it moves to the visited network for the first time without EPLMN, it happens to be in the scenario of no home network signal, then the visited network will successfully accept the UE's registration request, regardless of whether the UE supports the voice service capabilities of the visited network. If the UE does not support the voice service capabilities of the visited network, the UE cannot use voice services in the visited network and will not actively return to the home network, which seriously affects the user experience.

In response to the above technical problems, the concept of the present application is to provide a method for setting an EPLMN list, a core network device and a medium, wherein the core network device sends the EPLMN list in a differentiated manner according to the capability information of the terminal and the visited network, thereby ensuring that when the terminal cannot use the voice service of the visited network, it does not roam to the visited network through reselection or redirection, and can reduce the frequent network selection operations of the terminal, or can ensure that when the terminal cannot use the voice service in the visited network, it can actively return to the home network, thereby solving the problem that the existing method for setting the EPLMN list cannot be differentiated according to the capability information of the terminal and the visited network, which easily leads to the situation that the terminal cannot use the voice service after moving to the visited network, or when the terminal cannot use the voice service in the visited network, it cannot actively return to the home network, seriously affecting the user experience.

After introducing the basic principles of the present application, various non-limiting embodiments of the present application will be described in detail with reference to the accompanying drawings.

Embodiment 1:

This embodiment provides a method for setting an EPLMN list, which is applied to a core network device. As shown in FIG2 , the method includes:

Step S101: Acquire capability information of the terminal and capability information of the visited network.

It should be noted that when the current network is a 4G network, a method for setting an EPLMN list provided by the present invention can be applied to the MME of the current network. When the current network is a 5G network, a method for setting an EPLMN list provided by the present invention can be applied to the AMF of the current network, wherein, in a scenario with a home network, the current network refers to the home network, and in a scenario without a home network, the current network refers to the visited network.

Optionally, before acquiring the capability information of the terminal, the method further includes:

receiving an attach request/registration request from the terminal, and acquiring registration information of the terminal from the attach request/registration request from the terminal;

Determining whether the terminal meets the core network roaming condition according to the registration information;

The acquiring of the capability information of the terminal and the capability information of the visited network specifically includes:

If the terminal meets the core network roaming condition, capability information of the terminal and capability information of the visited network are obtained.

In this embodiment, when the terminal is attached to the 4G home network/visited network, an attach request is sent to the core network device, which carries the registration information of the terminal. When the terminal is registered in the 5G home network/visited network, a Registration request is sent to the core network device, which carries the registration information of the terminal.

In this embodiment, the registration information may include at least one of the following: location information of the terminal, such as TAC (Tracking Area Code), IMSI (International Mobile Subscriber Identity), IMEI (International Mobile Equipment Identity), MSISDN (Mobile Subscriber International ISDN), IMS (IP Multimedia Subsystem), voice capability, short message capability and emergency call capability, etc.

Specifically, it may be determined whether the terminal meets the core network roaming condition according to the location information, and/or IMSI, and/or IMEI, and/or MSISDN of the terminal.

In this embodiment, different operators can set different core network roaming conditions according to the implementation situation. For example, the core network equipment can determine whether the terminal meets the core network roaming conditions based only on the TAC location information or IMSI of the terminal, or it can determine whether the terminal meets the core network roaming conditions based on a combination of TAC location information and IMSI.

In this embodiment, when the core network device determines that the terminal meets the core network roaming conditions, the terminal capability information is obtained, and the terminal capability information may include new radio voice VoNR capability and/or evolved packet circuit domain fallback EPS FB capability, and may also include IMS voice capability, emergency call capability, etc. Among them, EPS FB capability, IMS voice capability and emergency call capability can be obtained from the registration information.

Optionally, acquiring the VoNR capability of the terminal may specifically include:

Receiving a UE wireless capability information indication message sent by a wireless network device;

The UE radio capability information indication message is parsed to obtain the VoNR capability of the terminal.

In this embodiment, the wireless network device is a base station, and the base station first initiates a UE capability enquiry message to the terminal, and requests the terminal's capability information, including VoNR capability, supported frequency band information, etc. The terminal sends UE capability information to the base station, which carries the key capability field requested by the network, and then the base station sends a UE RADIO CAPABILITY INFO INDICATION message to the core network device, which carries the UE capability information. It should be noted that according to the 3GPP protocol, the existing core network device does not parse the UE capability information of the terminal, and if the terminal's capability information is not parsed, the core network device cannot know the terminal's VoNR capability. Therefore, in the present invention, when the core network device receives the UE radio capability information indication message carrying the UE capability information sent by the wireless network device, the message can be directly parsed to obtain the terminal's VoNR capability.

Optionally, acquiring the VoNR capability of the terminal may specifically include:

Sending a first request message to a wireless network device, where the first request message is used to request to obtain the VoNR capability of the terminal;

Receiving a first response message sent by the wireless network device based on the first request message, where the first response message carries a VoNR capability field;

The VoNR capability of the terminal is obtained according to the value of the VoNR capability field, wherein if the value of the VoNR capability field is supported, it indicates that the terminal has the VoNR capability and is in an on state; if the value of the VoNR capability field is not supported, it indicates that the terminal does not have the VoNR capability or has the VoNR capability but the VoNR capability is in a off state.

In this embodiment, in order to avoid excessive processing delays caused by excessive capability reading when parsing the UE wireless capability information indication message, the present invention carries the VoNR capability field in the pre-designed first request message and the first response message, so that the core network device can obtain the VoNR capability of the terminal without parsing the UE wireless capability information indication message. Among them, the value of the VoNR capability field can be supported (supported) or not supported (notsupported), which is consistent with the VoNR capability indication in UECapabilityinformation. If the terminal supports VoNR capability (that is, the terminal has VoNR capability and is in the turned-on state), the value is supported (supported), otherwise it is not supported (notsupported).

Optionally, the sending a first request message to the wireless network device specifically includes:

Sending a user terminal device UE radio capability match request message (UE RADIOCAPABILITY MATCH REQUEST) or a UE radio capability check request message (UE RADIO CAPABILITY CHECKREQUEST) to the wireless network device;

The receiving a first response message sent by the wireless network device based on the first request message may specifically include:

receiving a UE radio capability match response message (UE RADIO CAPABILITY MATCH RESPONSE) sent by the wireless network device based on the UE radio capability match request message; or,

A UE radio capability check response message (UE RADIO CAPABILITY CHECK RESPONSE) is received, which is sent by the wireless network device based on the UE radio capability check request message.

In this embodiment, if the home network/visited network is a 4G network, in order to obtain the VoNR capability of the terminal, the UE radio capability match request message (UE RADIOCAPABILITY MATCH REQUEST) sent by the core network device (MME) to the wireless network device (eNB) and the UE radio capability match response message (UE RADIOCAPABILITY MATCH RESPONSE) sent by the eNB to the MME carry the VoNR (Voice over NR) capability field. The description of the VoNR (Voice over NR) capability field is shown in Table 1 and Table 2:

Table 1: Description of VoNR capability fields in UE RADIO CAPABILITY MATCH REQUEST

Table 2: Description of VoNR capability fields in UE RADIO CAPABILITY MATCH RESPONSES

In this embodiment, if the home network/visited network is a 5G network, in order to obtain the VoNR capability of the terminal, the UE radio capability check request message (UE RADIOCAPABILITY CHECK REQUEST) sent by the core network device (AMF) to the radio network device (gNB) and the UE radio capability check response message (UE RADIOCAPABILITY CHECK RESPONSE) sent by the gNB to the AMF may carry the VoNR (Voice over NR) capability field. The description of the VoNR (Voice over NR) capability field is shown in Table 3 and Table 4:

Table 3: Description of VoNR capability fields in UE RADIO CAPABILITY CHECK REQUEST

Table 4: Description of VoNR capability fields in UE RADIO CAPABILITY CHECK RESPONSE

Step S102: judging whether the terminal satisfies a condition of setting a roaming PLMN of the visited network and a home PLMN of the home network to be equivalent, according to the capability information of the terminal and the capability information of the visited network.

Step S103: If the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent, the roaming PLMN of the visited network or the home PLMN of the home network is carried in the EPLMN list and sent to the terminal.

In this embodiment, the core network of the home network and the core network of the visited network both pre-store capability information of both parties, such as N26 support, VoNR support, EPS FB (EPS Fallback, Evolved Packet Circuit Domain Fallback) support, supported network frequency information, etc.

Optionally, judging, according to the capability information of the terminal and the capability information of the visited network, whether the terminal satisfies a condition for setting a roaming PLMN of the visited network and a home PLMN of the home network to be equivalent specifically includes:

According to the VoNR capability and/or EPS FB capability of the terminal and the VoNR capability and EPS FB capability of the visited network, it is determined whether the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

Optionally, judging whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent according to the VoNR capability and/or EPS FB capability of the terminal and the VoNR capability and EPS FB capability of the visited network, specifically includes at least one of the following:

If the visited network supports the VoNR capability and the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPSFB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability and the EPS FB capability, the terminal does not support the VoNR capability and the EPSFB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal supports the VoNR capability, determining that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal does not support the VoNR capability but supports the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the EPS FB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the VoNR capability but does not support the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability and does not support the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support VoNR capability and EPS FB capability, the terminal does not support VoNR capability and EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the conditions for setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

In this embodiment, the core network device can specifically determine whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent based on the capability information of the terminal shown in Table 5 and the capability information of the visited network. If the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, the roaming PLMN is sent as EPLMN; otherwise, the roaming PLMN is not sent as EPLMN.

Table 5: Correspondence between capability information and whether the roaming PLMN is EPLMN:

In this embodiment, in addition to the situation shown in Table 5, in actual applications, the core network device can also determine whether to send the EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network according to other capability information of the terminal or the visited network. For example, considering that the visited network can only provide 5G services but does not support IMS emergency calls, even if the terminal supports VoNR, the emergency call service cannot be used, and the core network device does not open the core network roaming service for such users. That is, if the visited network supports IMS voice and VoNR, but does not support EPS FB and IMS emergency calls, the terminal supports IMS voice and the visited network frequency, and the TAC location information belongs to the core network roaming area, supports VoNR and IMS emergency calls, the EPLMN list is not sent, otherwise the EPLMN list is sent. For another example, considering that some user information such as IMSI, MSISDN, IMEI and other information can be obtained by the network, if the user clearly indicates that he does not want to sign up for the core network roaming service, the network should be able to not activate the core network roaming service for the user based on the IMSI, MSISDN, IMEI and other information. That is, if the visited network supports IMS voice and VoNR, but does not support EPS FB, the terminal supports IMS voice and the visited network frequency, and the TAC location information belongs to the core network roaming area, but IMSI = xxx, or IMEI = yyy, or MSISDN = zzz, then the EPLMN list will not be issued, otherwise the EPLMN list will be issued.

Furthermore, the rules for sending the EPLMN list can be customized to different degrees according to the needs of operators. For example, according to the terminal's IMSI, IMEI, VoNR or the frequency of the visited network, IMS capability, EPSFB capability and other information, the EPLMN list can be sent or not sent to the single terminal level, and according to the terminal's location information (TAC) and VoNR information, the EPLMN list can be sent or not sent to the terminals in an area.

Optionally, acquiring the VoNR capability of the terminal specifically includes:

receiving a Tracking Area Update (TAU) message or a Mobility Registration Update (MRU) message sent by a terminal, wherein the Tracking Area Update message or the Mobility Registration Update message carries the VoNR capability of the terminal;

The VoNR capability of the terminal is obtained from the tracking area update message or the mobile registration update message.

In this embodiment, when a terminal that does not support VoNR capability (for example, the terminal has VoNR capability but the VoNR capability is in the turned-off state) successfully attaches to the 4G core network, the EPLMN list is not obtained. At this time, the UE turns on the VoNR function (that is, the VoNR capability is in the turned-on state). At this time, the voice capability of the terminal changes, and the terminal initiates a TAU process, which includes UE capability reporting. The VONR function has been turned on. The core network device re-judges whether the terminal meets the EPLMN list issuance conditions based on the changed VoNR capability of the terminal. If satisfied, a TAU accept (TAU accept message) is issued, which carries the EPLMN list.

In this embodiment, when a terminal that does not support VoNR capability (for example, the terminal has VoNR capability but the VoNR capability is in the turned-off state) successfully registers in the 5G core network, the EPLMN list is not obtained. At this time, the UE turns on the VoNR function (that is, the VoNR capability is in the turned-on state). At this time, the voice capability of the terminal changes, and the terminal initiates the MRU process, which includes UE capability reporting. The VONR function has been turned on, and the core network device of the home network re-determines whether the terminal meets the conditions for sending the EPLMN list based on the changed VoNR capability of the terminal. If so, it sends an MRU accept (MRU accept message) carrying the EPLMN list.

Optionally, carrying the roaming PLMN of the visited network or the home PLMN of the home network in the EPLMN list and sending it to the terminal specifically includes:

If the core network device is a home network core network device, the roaming PLMN of the visited network is carried in the EPLMN list and sent to the terminal;

If the core network device is a visited network core network device, the home PLMN of the home network is carried in the EPLMN list and sent to the terminal.

In this embodiment, in a scenario with a home network, the terminal resides in the home network, and when the home network core network device determines that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network as equivalent, the roaming PLMN of the visited network is carried in the EPLMN list and sent to the terminal; correspondingly, in a scenario without a home network, the terminal resides in the visited network, and when the visited network core network device determines that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network as equivalent, the home PLMN of the home network is carried in the EPLMN list and sent to the terminal.

Optionally, carrying the roaming PLMN of the visited network or the home PLMN of the home network in the EPLMN list and sending it to the terminal specifically includes:

Sending an EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network to the terminal through an attach accept message/registration accept message; or,

An EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network is sent to the terminal through a tracking area update accept message/mobile registration update accept message.

In this embodiment, if the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, an attachment acceptance message (attachaccept)/registration acceptance message (Registration accept) carrying the EPLMN list is sent to the terminal, or a tracking area update acceptance message/mobile registration update acceptance message carrying the EPLMN list is sent to the terminal.

It should be noted that the method for setting the EPLMN list provided by the present invention does not modify the EPLMN list message body, but only adds judgment logic and processing filters at the core network level, so that the core network can distribute the EPLMN list to terminals with different capabilities without modifying the terminals and wireless networks as much as possible, thereby improving the user experience.

Optionally, the method further comprises:

If the core network device is a home network core network device and the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, the EPLMN list is not sent to the terminal, or the EPLMN list without the roaming PLMN of the visited network is sent to the terminal.

Optionally, the method further comprises:

If the core network device is a visited network core network device and the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, the terminal access is denied, and an attachment failure message/registration failure message carrying a rejection reason value is sent to the terminal, or a tracking area update failure message/mobile registration update failure message carrying a rejection reason value is sent to the terminal.

In this embodiment, the tracking area update failure message/mobile registration update failure message may carry a rejection reason value, such as: #11 PLMN not allowed, #12 Tracking area not allowed, #13 roaming not allowed in this tracking area; #15 No suitable Cells in tracking area, etc.

In a specific embodiment, the network in which the terminal currently resides is a 4G network, the core network device is an MME of a home network/visited network, the wireless network device is an eNB of a home network/visited network, and the terminal is a 5G terminal. The method for setting the EPLMN list may include the following steps:

(1) When the 5G terminal is turned on and selects a network, it will give priority to logging in to the frequency point where the HPLMN (Home Public Land Mobile Network) is located.

(2) After the 5G terminal searches for the 4G signal and successfully accesses the 4G signal, it initiates an attach request to the MME of the 4G core network. The request carries the IMSI, IMEI, location information (TAC), IMS voice capability (IMS PS Voice preferred, i.e., IMS packet domain voice priority, CS Voice as secondary, i.e., circuit domain voice priority second), short message capability, emergency call capability, etc., and is sent directly to the MME of the core network through a NAS message.

(3) The eNB initiates a UE capability enquiry to the 5G terminal, and requests the 5G capability information of the terminal. When the 5G terminal supports VoNR, the VoNR capability can be identified in the VoiceoverNR carried in the UE capability message and sent to the 4G eNB. The method for transmitting UE capability information between the 4G wireless network and the core network is as follows:

a) After receiving the attach request, the core network MME can obtain the location information (such as TAC), IMSI, IMEI, MSISDN and other information of the 5G terminal. Based on this information, the MME can determine whether the 5G terminal meets the core network roaming conditions, and thus perform special actions for such terminals. That is, when the MME determines that the 5G terminal meets the conditions for core network roaming, the MME sends a UE RADIO CAPABILITY MATCH REQUEST message to the eNB to request the VoNR capability of the 5G terminal from the eNB, or the MME needs to start this process for all 5G terminals. A new Voice over NR field is set in the message body of UE RADIO CAPABILITY MATCH REQUEST and UE RADIO CAPABILITY MATCH RESPONSE, with a value of supported or not supported. This value is consistent with the VoNR capability indication in UECapabilityInformation. When the eNB parses the UE radio capability and finds that the VoiceoverNR field is supported, it replies in the UE RADIOCAPABILITY CHECK RESPONSE message that VoiceoverNR is supported, so that the MME successfully obtains the VoNR capability of the 5G terminal.

b) The eNB sends the UE capability message to the MME, which directly parses and reads the VoNR capability of the 5G terminal.

(4) MME obtains the capability information of the 5G terminal and stores it.

(5) The MME determines whether the 5G terminal satisfies the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent. If so, the MME jumps to step (7); otherwise, the MME jumps to step (6):

Specifically, if the visited network supports the VoNR capability and the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPS FB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability and the EPS FB capability, the terminal does not support the VoNR capability and the EPSFB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal supports the VoNR capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal does not support the VoNR capability but supports the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability but does not support the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the EPS FB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the VoNR capability but does not support the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability but supports the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability and does not support the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support VoNR capability and EPS FB capability, the terminal does not support VoNR capability and EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the conditions for setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

(6) The MME sends an attach accept message to the 5G terminal without carrying the EPLMN list.

(7) The MME sends an attach accept message to the 5G terminal, carrying the EPLMN list, to set the roaming PLMN of the visited network and the home PLMN of the home network as equivalent PLMNs.

In another specific embodiment, if the network in which the terminal currently resides is a 5G network, the core network device is the AMF of the home network/visited network, the wireless network device is the gNB of the home network/visited network, and the terminal is a 5G terminal, the setting method of the EPLMN list may include the following steps:

(1) When the 5G terminal is turned on and selects a network, the frequency point where the HPLMN is located is given priority for logging in.

(2) After the 5G terminal searches for the 5G signal and successfully accesses the 5G signal, it initiates a Registration request to the AMF of the 5G core network. The request carries IMSI, IMEI, location information (TAC), IMS voice capability (IMS PS Voice preferred, i.e., IMS packet domain voice priority, CS Voice as secondary, i.e., circuit domain voice priority second), short message capability, emergency call capability, etc., and is sent directly to the AMF of the core network through a NAS message.

(3) The gNB initiates a UE capability enquiry to the 5G terminal, and requests the 5G capability information of the terminal. When the 5G terminal supports VoNR, the VoNR capability can be identified in the VoiceoverNR carried in the UE capability message and sent to the 5G gNB. The method for transmitting UE capability information between the 5G wireless network and the core network is as follows:

a) After receiving the Registration request, the core network AMF can obtain the location information (such as TAC), IMSI, IMEI, MSISDN and other information of the 5G terminal. Based on this information, the AMF can determine whether the 5G terminal meets the core network roaming conditions, and thus perform special actions for such terminals. That is, when the AMF determines that the 5G terminal meets the conditions for core network roaming, the AMF sends a UE RADIO CAPABILITY CHECK REQUEST message to the gNB to request the VoNR capability of the 5G terminal from the gNB, or the AMF needs to start this process for all 5G terminals. A new Voice over NR field is set in the message body of UE RADIO CAPABILITY CHECK REQUEST and UE RADIO CAPABILITY CHECK RESPONSE, with a value of supported or not supported. This value is consistent with the VoNR capability indication in UECapabilityInformation. When the gNB parses the UE radio capability and finds that the VoiceoverNR field is supported, it replies in the UE RADIOCAPABILITY CHECK RESPONSE message that VoiceoverNR is supported, so that the AMF successfully obtains the VoNR capability of the 5G terminal.

b) gNB sends the UE capability message to AMF, which directly parses and reads the VoNR capability of the 5G terminal.

(4)AMF obtains the capability information of the 5G terminal and stores it.

(5) The AMF determines whether the 5G terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent. If so, it jumps to step (7); otherwise, it jumps to step (6):

Specifically, if the visited network supports the VoNR capability and the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPS FB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability and the EPS FB capability, the terminal does not support the VoNR capability and the EPSFB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal supports the VoNR capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal does not support the VoNR capability but supports the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network supports the VoNR capability but does not support the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the EPS FB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the VoNR capability but does not support the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability but supports the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support the VoNR capability and does not support the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

Specifically, if the visited network does not support VoNR capability and EPS FB capability, the terminal does not support VoNR capability and EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the conditions for setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

(6)AMF sends a Registration accept message to the 5G terminal without carrying the EPLMN list.

(7) The AMF sends a Registration accept message to the 5G terminal, carrying the EPLMN list, to set the roaming PLMN of the visited network and the home PLMN of the home network as equivalent PLMNs.

The method for setting the EPLMN list, the core network device and the medium provided by the present invention first obtain the capability information of the terminal and the capability information of the visited network; then, according to the capability information of the terminal and the capability information of the visited network, determine whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent; if the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, then the roaming PLMN of the visited network or the home PLMN of the home network is carried in the EPLMN list and sent to the terminal. Since the present invention can issue the EPLMN list in a differentiated manner according to the capability information of the terminal and the visited network, it can ensure that when the terminal cannot use the voice service of the visited network, it does not roam to the visited network through reselection or redirection, and can reduce the frequent network selection operations of the terminal, or can ensure that when the terminal cannot use the voice service in the visited network, it can actively return to the home network, thereby solving the problem that the existing method for setting the EPLMN list cannot set it in a differentiated manner according to the capability information of the terminal and the visited network, which easily leads to the situation that the terminal cannot use the voice service after moving to the visited network, or when the terminal cannot use the voice service in the visited network, it cannot actively return to the home network, which seriously affects the user experience.

Embodiment 2:

As shown in FIG. 3 , this embodiment provides a core network device, which is used to execute the above-mentioned method for setting the EPLMN list, including:

A capability acquisition module 11 is used to acquire capability information of the terminal and capability information of the visited network;

A condition judgment module 12, connected to the capability acquisition module 11, is used to judge whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent according to the capability information of the terminal and the capability information of the visited network;

The list sending processing module 13 is connected to the condition judgment module 12, and is used to carry the roaming PLMN of the visited network or the home PLMN of the home network in the EPLMN list and send it to the terminal if the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

Optionally, the core network device further includes:

A registration information acquisition module, used to receive an attachment request/registration request of the terminal, and acquire the registration information of the terminal from the attachment request/registration request of the terminal;

A roaming condition determination module, configured to determine whether the terminal meets the core network roaming condition according to the registration information;

The capability acquisition module 11 is specifically used for:

If the terminal meets the core network roaming condition, capability information of the terminal and capability information of the visited network are obtained.

Optionally, the registration information includes: location information of the terminal, and/or international mobile subscriber identity code IMSI, and/or international mobile equipment identity code IMEI, and/or international mobile subscriber integrated services digital network MSISDN;

The roaming condition determination module is specifically used for:

Whether the terminal meets the core network roaming condition is determined according to the location information, and/or IMSI, and/or IMEI, and/or MSISDN of the terminal.

Optionally, the capability acquisition module 11 includes:

The terminal capability acquisition unit is used to acquire the new air interface voice VoNR capability and/or evolved packet circuit domain fallback EPS FB capability of the terminal.

Optionally, the terminal capability acquisition unit includes:

A first sending unit, configured to send a first request message to a wireless network device, where the first request message is used to request to obtain the VoNR capability of the terminal;

A first receiving unit, configured to receive a first response message sent by the wireless network device based on the first request message, where the first response message carries a VoNR capability field;

The first acquisition unit is used to acquire the VoNR capability of the terminal according to the value of the VoNR capability field, wherein if the value of the VoNR capability field is supported, it indicates that the terminal has VoNR capability and is in an on state; if the value of the VoNR capability field is not supported, it indicates that the terminal does not have VoNR capability or has VoNR capability but the VoNR capability is in a off state.

Optionally, the first sending unit is specifically configured to:

Sending a user terminal device UE wireless capability matching request message or a UE wireless capability check request message to the wireless network device;

The first receiving unit is specifically configured to:

receiving a UE wireless capability matching response message sent by the wireless network device based on the UE wireless capability matching request message; or,

A UE radio capability check response message is received, which is sent by the wireless network device based on the UE radio capability check request message.

Optionally, the terminal capability acquisition unit includes:

A second receiving unit, configured to receive a UE wireless capability information indication message sent by a wireless network device;

The parsing and obtaining unit is used to parse the UE radio capability information indication message to obtain the VoNR capability of the terminal.

Optionally, the condition judgment module 12 is specifically used for:

According to the VoNR capability and/or EPS FB capability of the terminal and the VoNR capability and EPS FB capability of the visited network, it is determined whether the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

Optionally, the condition judgment module 12 judges whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent according to at least one of the following:

If the visited network supports the VoNR capability and the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPSFB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability and the EPS FB capability, the terminal does not support the VoNR capability and the EPSFB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal supports the VoNR capability, determining that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, and the terminal does not support the VoNR capability but supports the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network supports the VoNR capability but does not support the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the EPS FB capability, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, and the terminal supports the VoNR capability but does not support the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability but supports the EPS FB capability, the terminal does not support the VoNR capability and the EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support the VoNR capability and does not support the EPS FB capability, and the terminal supports at least one of the VoNR capability and the EPS FB capability, it is determined that the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent;

If the visited network does not support VoNR capability and EPS FB capability, the terminal does not support VoNR capability and EPS FB capability and the terminal is a non-voice terminal, it is determined that the terminal meets the conditions for setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

Optionally, the terminal capability acquisition unit includes:

An update message receiving unit, configured to receive a tracking area update message or a mobile registration update message sent by a terminal, wherein the tracking area update message or the mobile registration update message carries the VoNR capability of the terminal;

The VoNR acquisition unit is used to acquire the VoNR capability of the terminal from the tracking area update message or the mobile registration update message.

Optionally, the list sending processing module 13 includes:

A first sending unit, configured to carry the roaming PLMN of the visited network in an EPLMN list and send the list to the terminal if the core network device is a home network core network device;

The second sending unit is used for carrying the home PLMN of the home network in the EPLMN list and sending it to the terminal if the core network device is a visited network core network device.

Optionally, the list sending processing module 13 includes:

a message sending unit, configured to send an EPLMN list carrying a roaming PLMN of the visited network or a home PLMN of the home network to the terminal through an attach accept message/registration accept message; or,

An EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network is sent to the terminal through a tracking area update accept message/mobile registration update accept message.

Optionally, the core network device further includes:

The first processing module is used for not sending the EPLMN list to the terminal, or sending the EPLMN list without the roaming PLMN of the visited network to the terminal, if the core network device is a core network device of the home network and the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent.

Optionally, the core network device further includes:

The second processing module is used to deny access to the terminal and send an attachment failure message/registration failure message carrying a rejection reason value to the terminal if the core network device is a visited network core network device and the terminal does not meet the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, or send a tracking area update failure message/mobile registration update failure message carrying a rejection reason value to the terminal.

Embodiment 3:

4 , this embodiment provides a core network device, including a memory 21 and a processor 22 , wherein the memory 21 stores a computer program, and the processor 22 is configured to run the computer program to execute the method for setting the EPLMN list in Embodiment 1.

The memory 21 is connected to the processor 22. The memory 21 may be a flash memory, a read-only memory or other memory. The processor 22 may be a central processing unit or a single-chip microcomputer.

Embodiment 4:

This embodiment provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the method for setting the EPLMN list in the above-mentioned embodiment 1 is implemented.

The computer-readable storage medium includes volatile or non-volatile, removable or non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, computer program modules or other data). Computer-readable storage media include, but are not limited to, RAM (Random Access Memory), ROM (Read-Only Memory), EEPROM (Electrically Erasable Programmable read only memory), flash memory or other memory technology, CD-ROM (Compact Disc Read-Only Memory), digital versatile disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer.

The core network equipment and media provided in Examples 2 to 4 first obtain the capability information of the terminal and the capability information of the visited network; then, based on the capability information of the terminal and the capability information of the visited network, determine whether the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent; if the terminal satisfies the condition of setting the roaming PLMN of the visited network and the home PLMN of the home network to be equivalent, the roaming PLMN of the visited network or the home PLMN of the home network is carried in the EPLMN list and sent to the terminal. Since the present invention can issue the EPLMN list in a differentiated manner according to the capability information of the terminal and the visited network, it can ensure that when the terminal cannot use the voice service of the visited network, it does not roam to the visited network through reselection or redirection, and can reduce the frequent network selection operations of the terminal, or can ensure that when the terminal cannot use the voice service in the visited network, it can actively return to the home network, thereby solving the problem that the existing method for setting the EPLMN list cannot set it in a differentiated manner according to the capability information of the terminal and the visited network, which easily leads to the situation that the terminal cannot use the voice service after moving to the visited network, or when the terminal cannot use the voice service in the visited network, it cannot actively return to the home network, which seriously affects the user experience.

It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims (16)

1. A method for setting an EPLMN list of a peer-to-peer public land mobile network, applied to a core network device, the method comprising:

Acquiring capability information of a terminal and capability information of a visiting network; the capability information of the terminal comprises VoNR capability and EPS FB capability of the terminal, and the capability information of the visiting network comprises VoNR capability and EPS FB capability of the visiting network;

Judging whether the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent according to the capability information of the terminal and the capability information of the visiting network; if the terminal does not support VoNR capability and EPS FB capability and is a non-voice terminal, judging that the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent;

And if the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent, carrying the roaming PLMN of the visiting network or the home PLMN of the home network in an EPLMN list and sending the roaming PLMN or the home PLMN of the home network to the terminal.

2. The method for setting an EPLMN list according to claim 1, wherein before the acquiring the capability information of the terminal, the method further comprises:

Receiving an attachment request/registration request of the terminal, and acquiring registration information of the terminal from the attachment request/registration request of the terminal;

judging whether the terminal meets the roaming condition of the core network according to the registration information;

the acquiring the capability information of the terminal and the capability information of the visiting network specifically comprises the following steps:

and if the terminal meets the roaming condition of the core network, acquiring the capability information of the terminal and the capability information of the visiting network.

3. The method for setting an EPLMN list according to claim 2, wherein the registration information includes: the position information of the terminal and/or the international mobile subscriber identity IMSI and/or the international mobile equipment identity IMEI and/or the international mobile subscriber integrated services digital network MSISDN;

the judging whether the terminal meets the roaming condition of the core network according to the registration information specifically comprises the following steps:

Judging whether the terminal meets the roaming condition of the core network according to the position information, and/or IMSI, and/or IMEI, and/or MSISDN of the terminal.

4. The method for setting an EPLMN list according to claim 1, wherein obtaining VoNR capabilities of the terminal specifically includes:

transmitting a first request message to a wireless network device, wherein the first request message is used for requesting to acquire VoNR capabilities of the terminal;

Receiving a first response message sent by the wireless network device based on the first request message, wherein the first response message carries VoNR capability fields;

And acquiring VoNR capability of the terminal according to the value of the VoNR capability field, wherein if the value of the VoNR capability field is supported, the terminal is VoNR capable and is in an on state, and if the value of the VoNR capability field is not supported, the terminal is not VoNR capable or VoNR capable but the VoNR capability is in an off state.

5. The method for setting an EPLMN list according to claim 4, wherein the sending the first request message to the wireless network device specifically includes:

Transmitting a user terminal equipment (UE) wireless capability matching request message or a UE wireless capability checking request message to the wireless network equipment;

the receiving the first response message sent by the wireless network device based on the first request message specifically includes:

Receiving a UE wireless capability matching response message sent by the wireless network device based on the UE wireless capability matching request message; or alternatively

And receiving a UE wireless capability check response message sent by the wireless network equipment based on the UE wireless capability check request message.

6. The method for setting an EPLMN list according to claim 1, wherein obtaining VoNR capabilities of the terminal specifically includes:

Receiving a UE wireless capability information indication message sent by wireless network equipment;

And analyzing the UE wireless capability information indication message to acquire VoNR capability of the terminal.

7. The method for setting an EPLMN list according to claim 1, wherein the determining whether the terminal satisfies a condition that a roaming PLMN of a visited network and a home PLMN of a home network are set to be equivalent according to capability information of the terminal and capability information of the visited network specifically includes:

and judging whether the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent according to VoNR capability and/or EPS FB capability of the terminal, and VoNR capability and EPS FB capability of the visiting network.

8. The method for setting an EPLMN list according to claim 7, wherein the determining, according to VoNR capabilities and/or EPS FB capabilities of the terminal and VoNR capabilities and EPS FB capabilities of the visited network, whether the terminal satisfies a condition that a roaming PLMN of the visited network and a home PLMN of the home network are set to be equivalent specifically includes at least one of:

if the visited network supports VoNR capabilities and EPS FB capabilities, and the terminal supports at least one of VoNR capabilities and EPS FB capabilities, determining that the terminal satisfies a condition that a roaming PLMN of the visited network and a home PLMN of the home network are set to be equivalent;

If the visited network supports VoNR capabilities and supports EPS FB capabilities, the terminal does not support VoNR capabilities and EPS FB capabilities and is a non-voice terminal, judging that the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent;

If the visited network supports VoNR capabilities but does not support EPS FB capabilities, the terminal supports VoNR capabilities, determining that the terminal satisfies a condition that a roaming PLMN of the visited network and a home PLMN of the home network are set to be equivalent;

If the visited network supports VoNR capabilities but does not support EPS FB capabilities, the terminal does not support VoNR capabilities but supports EPS FB capabilities, determining that the terminal does not meet a condition that a roaming PLMN of the visited network and a home PLMN of the home network are set to be equivalent;

If the visited network supports VoNR capabilities but does not support EPS FB capabilities, the terminal does not support VoNR capabilities and EPS FB capabilities and is a non-voice terminal, judging that the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent;

If the visited network does not support VoNR capabilities but supports EPS FB capabilities, the terminal supports EPS FB capabilities, judging that the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent;

If the visited network does not support VoNR capabilities but supports EPS FB capabilities, the terminal supports VoNR capabilities but does not support EPS FB capabilities, judging that the terminal does not meet the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent;

if the visited network does not support VoNR capabilities but supports EPS FB capabilities, the terminal does not support VoNR capabilities and EPS FB capabilities and is a non-voice terminal, judging that the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent;

If the visited network does not support VoNR capability or EPS FB capability, and the terminal supports at least one of VoNR capability and EPS FB capability, judging that the terminal does not meet the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent;

If the visited network does not support VoNR capabilities and does not support EPS FB capabilities, the terminal does not support VoNR capabilities and EPS FB capabilities and is a non-voice terminal, judging that the terminal meets the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent.

9. The method for setting an EPLMN list according to claim 1, wherein obtaining VoNR capabilities of the terminal specifically includes:

receiving a tracking area update message or a mobile registration update message sent by a terminal, wherein the tracking area update message or the mobile registration update message carries VoNR capacity of the terminal;

and acquiring VoNR capability of the terminal from the tracking area update message or the mobile registration update message.

10. The method for setting an EPLMN list according to claim 1, wherein the sending the EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network to the terminal specifically includes:

If the core network equipment is home network core network equipment, carrying a roaming PLMN of the visiting network in an EPLMN list and sending the roaming PLMN to the terminal;

And if the core network equipment is visited network core network equipment, carrying the home PLMN of the home network in an EPLMN list and sending the home PLMN to the terminal.

11. The method for setting an EPLMN list according to claim 1, wherein the sending the EPLMN list carrying the roaming PLMN of the visited network or the home PLMN of the home network to the terminal specifically includes:

sending an EPLMN list carrying a roaming PLMN of the visited network or a home PLMN of a home network to the terminal through an attach accept message/registration accept message; or alternatively

And sending an EPLMN list carrying the roaming PLMN of the visiting network or the home PLMN of the home network to the terminal through a tracking area update accept message/a mobile registration update accept message.

12. The method for setting an EPLMN list according to claim 1, further comprising:

If the core network device is home network core network device and the terminal does not meet the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent, the EPLMN list is not sent to the terminal, or the EPLMN list which does not carry the roaming PLMN of the visited network is sent to the terminal.

13. The method for setting an EPLMN list according to claim 1, further comprising:

If the core network device is a visited network core network device and the terminal does not meet the condition that the roaming PLMN of the visited network and the home PLMN of the home network are set to be equivalent, rejecting the access of the terminal, and sending an attach failure message/registration failure message carrying a reject cause value to the terminal, or sending a tracking area update failure message/mobile registration update failure message carrying a reject cause value to the terminal.

14. A core network device, comprising:

the capability acquisition module is used for acquiring capability information of the terminal and capability information of the visiting network; the capability information of the terminal comprises VoNR capability and EPS FB capability of the terminal, and the capability information of the visiting network comprises VoNR capability and EPS FB capability of the visiting network;

The condition judging module is connected with the capability acquiring module and is used for judging whether the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent according to the capability information of the terminal and the capability information of the visiting network; if the terminal does not support VoNR capability and EPS FB capability and is a non-voice terminal, judging that the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent;

And the list issuing processing module is connected with the condition judging module and is used for carrying the roaming PLMN of the visiting network or the home PLMN of the home network in the EPLMN list and sending the EPLMN list to the terminal if the terminal meets the condition that the roaming PLMN of the visiting network and the home PLMN of the home network are set to be equivalent.

15. A core network device comprising a memory and a processor, the memory having stored therein a computer program, the processor being arranged to run the computer program to implement a method of setting an EPLMN list as claimed in any one of claims 1 to 13.

16. A computer-readable storage medium, characterized in that the computer-readable storage medium has stored thereon a computer program which, when executed by a processor, implements a method of setting an EPLMN list according to any of claims 1-13.