WO2019041897A1

WO2019041897A1 - Network communication method and device

Info

Publication number: WO2019041897A1
Application number: PCT/CN2018/087890
Authority: WO
Inventors: 李永翠; 李岩; 李欢; 唐廷芳
Original assignee: 华为技术有限公司
Priority date: 2017-08-29
Filing date: 2018-05-22
Publication date: 2019-03-07
Also published as: CN109451577B; CN109451577A

Abstract

Disclosed in the present application are a network communication method and device, for use in resolving the problem of being unable to ensure, by a UDM entity, simultaneous network registration success of two AMF entities responsible for mobility management of one terminal device. In the solution, when a terminal device has accessed a first PLMN and is to access a second PLMN, the terminal device or a UDM entity may decide, when the access types of access technologies employed by the terminal device to access the two PLMNs are different, that the UDM entity still retain registration information of a first AMF entity response for mobility management during the access of the terminal device to the first PLMN. In this way, the UDM entity may register a second AMF entity response for mobility management during the access of the terminal device to the second PLMN, and may also not deregister the first AMF entity. Thus, dual registration of the first AMF entity and the second AMF entity is implemented.

Description

Network communication method and device

This application claims the priority of the Chinese Patent Application, filed on Aug. 29, 2017, the application Serial No. .

Technical field

The present application relates to the field of communications technologies, and in particular, to a network communication method and device.

Background technique

Currently, when accessing a public land mobile network (PLMN), the terminal device needs to perform network registration with the core network for the PLMN by:

The access and mobility management function (AMF) entity responsible for the mobility management of the terminal device in the core network passes the location management procedure to the unified data management (UDM) entity. Network registration is performed to notify the UDM of the information of the AMF entity. After the AMF entity registers with the UDM entity, the UDM maintains information of the AMF entity for the terminal device.

Typically, a UDM entity in the core network maintains, for each terminal device, information about an AMF entity responsible for mobility management of the terminal device. Therefore, when the terminal device accesses the PLMN through the first AMF entity by using the access technology of the first access type (such as the 3rd generation partnership project (3GPP) access type), the UDM will Saving information of an entity of the first AMF responsible for mobility management of the terminal device; after the terminal device accesses the PLMN, the terminal device further adopts a second access type (eg, non-3GPP access When the access technology accesses the PLMN through the second AMF entity, the UDM entity replaces the information of the first AMF entity with the information of the second AMF entity.

With the development of communication technologies for terminal devices, many terminal devices (such as smart phones, tablets, etc.) currently have dual connectivity capabilities, that is, access to PLMNs using access technologies using 3GPP access types and non-3GPP access types. . However, in the traditional network registration process, the UDM entity in the core network can only store information about the AMF entity responsible for the mobility management of the terminal device for one terminal device. Therefore, when the terminal device needs to access different PLMNs through different AMF entities by using the access technologies of the two access types, the UDM cannot guarantee that the two AMF entities simultaneously register successfully, which further The network access of the terminal device is affected, so that the terminal device frequently initiates a network registration process, which causes unnecessary signaling overhead, and thus affects the service of the terminal device.

Summary of the invention

The present application provides a network communication method and device for solving the problem that a UDM entity cannot guarantee that two AMF entities responsible for mobility management of the same terminal device are successfully registered at the same time.

In a first aspect, an embodiment of the present application provides a network communication method, where the method may include the following steps:

First, the terminal device acquires the first access type to which the first access technology is used when accessing the first public land mobile network (PLMN), and the second access mode to which the second access technology is used when accessing the second PLMN. a type, where the first PLMN is a PLMN to which the terminal device has access, the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a 3GPP access plan 3GPP access type and/or non a 3GPP access type, where the second access type is a 3GPP access type or a non-3GPP access type; and then, when the terminal device determines that the second access type is different from the first access type, sending the data to the unified data management UDM entity a first registration indication to indicate that the UDM entity retains registration information of the first access and mobility management function AMF entity, wherein the first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN.

In the above method, when the terminal device has accessed the first PLMN and is to access the second PLMN, the terminal device may use the access technology to which the access technology belongs when the terminal device accesses the two PLMNs. And determining that the UDM entity still retains registration information of the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but also may not deregister the first AMF entity, thereby implementing the first AMF entity and Double registration of the second AMF entity. With the above solution, the UDM can simultaneously store the registration information of the two AMF entities responsible for the mobility management of the same terminal device. Therefore, when the terminal device determines that the access technology corresponding to the two different access types is used to access the PLMN, It is ensured that two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, so that the terminal device can implement access technologies corresponding to two different access types at the same time, and access the PLMN through two AMF entities. In addition, the solution can prevent the terminal device from frequently initiating a network registration process, reduce unnecessary signaling overhead, and improve network access performance and service performance of the terminal device.

In a possible design, before the terminal device sends the first registration indication to the UDM entity, the terminal device further needs to determine that the identifier of the second PLMN is different from the identifier of the first PLMN.

In the mobile communication system, when the identifier of the first PLMN is different from the identifier of the second PLMN, and the second access type is different from the first access type, the terminal device is responsible for the 3GPP access type. The AMF entity that manages mobility when accessing the PLMN must be a different AMF entity from the AMF entity responsible for mobility management when the terminal device accesses the PLMN through the non-3GPP access type. Therefore, the terminal device indicates that the UDM entity retains the first in the case that it is determined that the second access type is different from the first access type, and the identifier of the second PLMN is different from the identifier of the first PLMN. An AMF registration information, ie, no registration for the first AMF. In this way, after the UDM entity successfully registers the second AMF entity, the UDM entity can simultaneously save the registration information of the two AMF entities responsible for the mobility management of the same terminal device, and the terminal device can implement two different connections simultaneously. The access technology corresponding to the entry type, and accesses two PLMNs through two AMF entities respectively.

In a possible design, before the terminal device sends the first registration indication to the UDM entity, the terminal device further needs to determine that the terminal device has dual connectivity capability, wherein the dual connectivity capability is used to indicate that the terminal device supports At the same time, access technologies of two access types are used to access the PLMN.

If the terminal device has dual connectivity capabilities, the terminal device can access the PLMN by using access technologies of two access types at the same time. Therefore, after the terminal device determines that it has dual connectivity capability, it indicates that the UDM entity does not perform registration on the first AMF entity. After the UDM entity registers the second AMF entity, the UDM entity may At the same time, the registration information of the two AMF entities responsible for the mobility management of the same terminal device is saved, and the terminal device can access the PLMN by using the access technologies of the two access types.

In a possible design, the dual connectivity capability may also indicate that the terminal device supports access to two different PLMNs using both access types of access technologies.

In a possible design, the terminal device can obtain the second access type by:

The first mode: the terminal device sends a request for carrying the location information of the terminal device to the ANDSF entity;

The ANDSF entity provides the terminal device with information about an access network that can be used in the vicinity of the terminal device according to an operator policy, including an access technology used by the terminal device to access the access network, and/or the access technology. Access type);

The terminal device may determine the second access type according to the information of the access network provided by the ANDSF entity. For example, after the terminal device determines that the terminal device accesses the access technology used by the access network, determines the second access type to which the access technology belongs according to the correspondence between the access type and the access technology included in the access device. .

The second mode: the terminal device performs signal measurement on the signal sent by the received 3GPP access network device and the signal sent by the non-3GPP access network device, and selects the target access network device with high signal transmission efficiency;

The terminal device determines an access technology used by the target access network device to determine a second access type to which the access technology belongs; or the terminal device determines the second access type corresponding to the target access network device.

With this design, the terminal device can determine the second access type.

In a possible design, the terminal device saves the second PLMN and the second access after determining the second access type when the second PLMN is to be accessed by using any one of the foregoing designs. Types of. Correspondingly, the terminal device may determine the first access type by using any one of the foregoing manners when the first PLMN is to be accessed, and save the first PLMN and the first access type. In this way, the terminal device can read the saved first access type, thereby acquiring the first access type.

In a possible design, the terminal device may send the first registration indication to the UDM entity by using the second AMF entity, where the second AMF entity is responsible for mobility management when the terminal device accesses the second PLMN. For example, the terminal device may carry the first registration indication in an RRC message or a registration request, and send the information to the second AMF entity by using the access network device, where the second AMF entity carries the first registration indication in the update location. The request is sent to the UDM entity. In this way, the terminal device can successfully send the first registration indication to the UDM entity.

In a possible design, the first registration indication sent by the terminal device to the UDM entity by the second AMF entity may further notify the UDM entity to register the second AMF entity.

With the design, after receiving the first registration indication sent by the second AMF entity, the UDM entity may also register the second AMF entity (save the registration information of the second AMF entity).

In a possible design, when the terminal device determines at least one of the following, sending a second registration indication to the UDM entity: the terminal device does not have dual connectivity capability; the second access type and the first access type the same;

The second registration indication is used to indicate that the UDM entity de-registers the first AMF entity, where the dual connectivity capability is used to indicate that the terminal device supports accessing the PLMN by using two access types of access technologies.

If the terminal device has accessed the first PLMN and is to access the second PLMN, the terminal device determines that the condition for sending the first registration indication is not met, and sends a second registration indication to the UDM entity to notify the UDM entity. Deregistering the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. The UDM entity may deregister the first AMF entity, that is, delete the registration information of the first AMF entity in the UDM entity, and therefore, the design may release the UDM entity occupied by the registration information of the first AMF entity. The storage space; in addition, the first AMF entity deletes the context of the terminal device in the process of deregistering the first AMF entity, and therefore, the design may further release the first AMF entity by the The storage space occupied by the context of the terminal device. In summary, the design can avoid the waste of the storage space in the UDM entity and the first AMF entity, and avoid the signaling overhead caused by the first AMF entity to the context maintenance of the terminal device.

In a possible design, when the terminal device determines at least one of the following, sending a second registration indication to the UDM entity: the terminal device does not have dual connectivity capability; the second access type and the first access type The same; the identifier of the second PLMN is the same as the identifier of the first PLMN;

In a possible design, the second registration indication is further configured to trigger the UDM entity to notify the first session management function SMF entity to release the session of the terminal device (eg, send a session release notification message to the first SMF entity), where The first SMF entity is responsible for session management when the terminal device accesses the first PLMN.

With this design, the UDM entity can not only deregister the first AMF entity, but also release the session of the terminal device to reduce the signaling overhead caused by the maintenance session of the first SMF entity.

In a possible design, when the terminal device determines that the second access type is different from the first access type, the terminal device may determine whether to send the second registration indication to the UDM entity by:

Manner 1: The terminal device determines the priority of the first PLMN; when the priority of the first PLMN is lower than the set PLMN priority threshold, the terminal device determines to send the second registration indication to the UDM entity;

Manner 2: the terminal device determines the priority of the session established when the terminal device accesses the first PLMN; when the priority of the session is lower than the set session priority threshold, the terminal device determines to send the session to the UDM entity. Second registration instruction;

Manner 3: the terminal device determines a priority of the service established when the terminal device accesses the first PLMN; when the priority of the service is lower than the set service priority threshold, the terminal device determines to send the service to the UDM entity Second registration instruction.

With the above design, the terminal device can determine whether to send the second registration indication to the UDM entity according to the preference of the terminal device. In this way, when the terminal device adopts the solution provided by the foregoing manner, the terminal device can ensure that the high priority PLMN accesses normally by comparing the priority of the PLMN with the PLMN priority threshold; When the solution is provided, the terminal device can ensure that the high-priority session is performed normally by comparing the priority of the session with the session priority threshold. When the terminal device adopts the solution provided by the foregoing mode 3, the terminal device can pass the service. The priority of the service is compared with the service priority threshold to ensure that the high-priority service works normally.

In a possible design, the terminal device may send the second registration indication to the UDM entity by using the second AMF entity, for example, the terminal device may carry the second registration indication in an RRC message or a registration request, and pass the The access network device sends the second AMF entity, and the second AMF entity carries the second registration indication to the UDM entity in the update location request. In this way, the terminal device can successfully send the second registration indication to the UDM entity.

In a possible design, the second registration indication sent by the terminal device to the UDM entity by the second AMF entity may further notify the UDM entity to register the second AMF entity.

With the design, after receiving the second registration indication sent by the second AMF entity, the UDM entity may also register the second AMF entity (save the registration information of the second AMF entity).

In a possible design, when the terminal device determines that the same target access type as the second access type exists in the first access type, sending a third registration indication to the UDM entity, where the The third registration indication is used to instruct the UDM entity to perform deregistration on the target AMF entity, where the target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN in the first PLMN, and the target PLMN adopts belonging to the terminal device The PLMN accessed by the access technology of the target access type.

If the terminal device has access to the PLMN by using the access technology corresponding to the two access types, if the terminal device needs to continue to access the PLMN by using the access technology corresponding to the access type, the terminal device may The UDM entity is notified by the third registration indication to deregister the target AMF entity. In this way, after the UDM entity successfully registers the second AMF entity, the UDM entity can ensure that the terminal device can access the PLMN by using the access technologies of the two access types at the same time, that is, the UDM entity is responsible for the terminal. The registration information of the two AMF entities of the mobility management when the device accesses the PLMN through the access technologies of the two access types. Therefore, the solution can ensure that two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, thereby preventing the terminal device from frequently initiating a network registration process, reducing unnecessary signaling overhead, and improving the network of the terminal device. Access performance and business performance.

In a possible design, the third registration indication is further configured to trigger the UDM entity to notify the target SMF entity to release the session of the terminal device (eg, send a session release notification message to the target SMF entity), where the target SMF entity is responsible for Session management when the terminal device accesses the target PLMN.

With this design, the UDM entity can not only deregister the target AMF entity, but also release the session of the terminal device to reduce the signaling overhead caused by the maintenance session of the target SMF entity.

In a possible design, the terminal device may send the third registration indication to the UDM entity by using the second AMF entity, for example, the terminal device may carry the third registration indication in an RRC message or a registration request, and pass the The access network device sends the second AMF entity, and the second AMF entity carries the third registration indication to the UDM entity in the update location request. In this way, the terminal device can successfully send a third registration indication to the UDM entity.

In a possible design, the third registration indication sent by the terminal device to the UDM entity by the second AMF entity may further notify the UDM entity to register the second AMF entity.

With the design, the UDM entity can also register the second AMF entity after receiving the third registration indication sent by the second AMF entity.

In a second aspect, the embodiment of the present application further provides a network communication method, where the method includes the following steps:

The unified data management UDM entity receives a first registration indication from the terminal device, where the first registration indication is used to indicate that the UDM entity retains registration information of the first access and mobility management function AMF entity, where the first AMF entity is responsible for the Mobility management when the terminal device accesses the first public land mobile network PLMN, the first PLMN is a PLMN that the terminal device has accessed;

The UDM entity retains registration information of the first AMF entity according to the first registration indication.

In one possible design, in a mobile communication system, the terminal device does not need to determine whether it has dual connectivity capability before transmitting the first registration indication. Then, in this case, before the UDM entity retains the registration information of the second AMF entity according to the first registration indication, the UDM entity determines that the terminal device has dual connectivity capability, wherein the dual connectivity capability is used to indicate The terminal device supports accessing the PLMN by using access technologies of two access types at the same time.

In this way, the UDM entity may not only deregister the first AMF entity but also the second mobility management when the terminal device accesses the second PLMN, if the terminal device has the dual connectivity capability. The AMF entity registers to implement dual registration of the first AMF entity and the second AMF entity.

In a possible design, the UDM entity can determine whether the terminal device has dual connectivity capability by using connection capability indication information received from the terminal device.

With this design, the UDM entity can determine whether the terminal device has dual connectivity capabilities.

In a possible design, the UDM entity receives the first registration indication sent by the terminal device forwarded by the second AMF entity, where the second AMF entity is responsible for mobility management when the terminal device accesses the second PLMN. In this way, the UDM entity can successfully receive the first registration indication sent by the terminal device.

In one possible design, the first registration indication may also notify the UDM entity to register the second AMF entity.

With this design, after receiving the first registration indication, the UDM entity can not only retain the registration information of the first AMF entity, but also register the second AMF entity.

In a third aspect, the embodiment of the present application further provides a network communication method, where the method includes the following steps:

First, the unified data management UDM entity acquires the first access type to which the first access technology is used when the terminal device accesses the first public land mobile network PLMN, and the second access technology used when accessing the second PLMN The second access type, wherein the first PLMN is a PLMN that the terminal device has accessed, and the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a third generation partner program. a 3GPP access type and/or a non-3GPP access type, the second access type being a 3GPP access type or a non-3GPP access type; then, when the UDM entity determines that the terminal device has dual connectivity capabilities, and the second When the access type is different from the first access type, the registration information of the first access and mobility management function AMF entity is reserved, where the first AMF entity is responsible for the mobility of the terminal device when accessing the first PLMN Management, the dual connectivity capability is used to indicate that the terminal device supports access to the PLMN by using two access types of access technologies simultaneously.

With the method, in the case that the terminal device has accessed the first PLMN and is to access the second PLMN, the UDM entity may determine that the terminal device has the dual connectivity capability, and the terminal device accesses the two PLMNs. When the access type to which the access technology belongs is different, it is determined that the UDM entity still retains registration information of the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but also may not deregister the first AMF entity, thereby implementing the first AMF entity and Double registration of the second AMF entity. Through the foregoing solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the UDM entity determines that the terminal device has dual connectivity capability, and the terminal device passes through two different connections. When the access technology corresponding to the access type accesses the PLMN, the two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, so that the terminal device can implement the corresponding access of the two different access types at the same time. Into the technology, and access to the PLMN through two AMF entities. In addition, the method can prevent the terminal device from frequently initiating a network registration process, reduce unnecessary signaling overhead, and improve network access performance and service performance of the terminal device.

In one possible design, the UDM entity may obtain, but is not limited to, the second access type by:

The first mode: the UDM entity can receive the second access type sent by the terminal device, where the second access type is determined by the terminal device.

The second mode: the UDM entity may receive the second access type sent by the second AMF entity, where the second AMF entity is responsible for mobility management when the terminal device accesses the second PLMN.

In the above manner, the UDM entity may determine the second access type when the terminal device is to access the second PLMN.

In a possible design, the UDM entity saves the second PLMN and the second access after determining the second access type when the terminal device is to access the second PLMN by using any one of the foregoing designs. Types of. Correspondingly, the UDM entity may determine the first access type by using any one of the foregoing manners when the terminal device is to be accessed by the first PLMN, and save the first PLMN and the first access type. In this way, the UDM entity can read the saved first access type to obtain the first access type.

In one possible design, before the UDM entity retains the registration information of the first AMF entity, the UDM entity may further determine that the identity of the second PLMN is different from the identity of the first PLMN.

In the mobile communication system, when the identifier of the first PLMN is different from the identifier of the second PLMN, and the second access type is different from the first access type, the terminal device is responsible for receiving the type through the 3GPP access type. The AMF entity that is mobility managed when entering the PLMN must be a different AMF entity from the AMF entity responsible for mobility management when the terminal device accesses the PLMN through the non-3GPP access type. Therefore, the UDM entity determines that the second access type is different from the first access type, and the identifier of the second PLMN is different from the identifier of the first PLMN, and the terminal device has dual connectivity capability. In case, the registration information of the first AMF entity is retained, that is, the first AMF is not registered. In this way, after the UDM entity successfully registers the second AMF entity, the UDM entity can simultaneously save the registration information of the two AMF entities responsible for the mobility management of the same terminal device, and the terminal device can implement two different connections simultaneously. The access technology corresponding to the entry type, and accesses two PLMNs through two AMF entities respectively.

In a possible design, when the UDM entity determines at least one of the following, the first AMF entity is deregistered: the terminal device does not have dual connectivity capability; the second access type and the first access type the same.

In the case that the terminal device has accessed the first PLMN and is to access the second PLMN, the UDM entity determines that the condition for retaining the registration information of the first AMF entity is not currently met, then the UDM entity goes to the first AMF entity. registered. With the above design, the UDM entity may deregister the first AMF entity, that is, delete the registration information of the first AMF entity in the UDM entity, and therefore, the solution may release the first AMF entity in the UDM entity. The storage space occupied by the registration information; in addition, the first AMF entity deletes the context of the terminal device in the process of deregistering the first AMF entity, so the solution may further release the first AMF. The storage space in the entity that is occupied by the context of the terminal device.

In a possible design, when the UDM entity determines at least one of the following, the first AMF entity is deregistered: the terminal device does not have dual connectivity capability; the second access type and the first access type The same; the identifier of the second PLMN is the same as the identifier of the first PLMN.

In a possible design, the UDM entity can determine whether the terminal device has dual connectivity capability by using the connection capability indication information reported by the terminal device.

In one possible design, the UDM entity notifies the first session management function SMF entity to release the session of the terminal device (eg, send a session release notification message to the first SMF entity), wherein the first SMF is responsible for the terminal device Session management when accessing the first PLMN.

In a possible design, when the UDM entity determines that the identifier of the first PLMN is different from the identifier of the second PLMN, and the first access type is different from the second access type, determining the first AMF entity Need to register and deregister the first AMF entity.

Optionally, the UDM entity may determine that the first AMF entity needs to be registered by:

Manner 1: The UDM entity determines the priority of the first PLMN; when the priority of the first PLMN is lower than the set PLMN priority threshold, the UDM determines that the first AMF entity needs to be registered;

Manner 2: The UDM entity determines a priority of a session established when the terminal device accesses the first PLMN; when the priority of the session is lower than a set session priority threshold, the UDM determines that the first AMF entity needs to go registered;

Manner 3: the UDM entity determines the priority of the service established when the terminal device accesses the first PLMN; when the priority of the service is lower than the set service priority threshold, the UDM determines that the first AMF entity needs to go registered.

Through the above method, the UDM entity can determine whether the first AMF entity needs to be registered according to the preference. In this way, when the UDM entity adopts the solution provided by the foregoing manner, the UDM entity can ensure that the high priority PLMN accesses normally by comparing the priority of the PLMN with the PLMN priority threshold; when the UDM entity adopts the foregoing manner 2 When the solution is provided, the UDM entity can ensure that the high-priority session is normal through the comparison between the priority of the session and the session priority threshold. When the UDM entity adopts the solution provided by the foregoing mode 3, the UDM entity can pass the service. The priority of the service is compared with the service priority threshold to ensure that the high-priority service works normally.

In a possible design, when the UDM entity determines that there is a target access type in the first access type that is the same as the second access type, the target AMF entity is deregistered;

The target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN in the first PLMN, and the target PLMN is a PLMN that the terminal device accesses by using an access technology belonging to the target access type.

With the above design, when the terminal device has accessed the PLMN by using the access technology corresponding to the two access types, if the terminal device needs to continue to access the PLMN by using the access technology corresponding to one of the access types, The UDM entity deregisters the target AMF entity. In this way, after the UDM entity successfully registers the second AMF entity, the UDM entity can ensure that the terminal device can access the PLMN by using the access technologies of the two access types at the same time, that is, the UDM is responsible for the terminal device. Registration information of two AMF entities of mobility management when accessing a PLMN through access technologies of two access types. Therefore, the solution can ensure that two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, thereby preventing the terminal device from frequently initiating a network registration process, reducing unnecessary signaling overhead, and improving the network of the terminal device. Access performance and business performance.

In a possible design, after determining that the target AMF entity is deregistered, the UDM entity notifies the target SMF entity to release the session of the terminal device, where the target SMF entity is responsible for the terminal device accessing the target PLMN. Session management.

In a fourth aspect, an embodiment of the present application provides a terminal device, including a unit or a means for performing the foregoing steps of the first aspect.

In a fifth aspect, an embodiment of the present application provides a UDM entity, including a unit or means for performing the foregoing steps of the second aspect.

In a sixth aspect, the embodiment of the present application further provides a UDM entity, including a unit or a means for performing the foregoing steps of the third aspect.

In a seventh aspect, the present application provides a terminal device including at least one processing element and at least one storage element, wherein the at least one storage element is configured to store a program and data, and the at least one processing element is configured to perform the first application of the present application. The method provided in the aspect.

In an eighth aspect, the present application provides a UDM entity including at least one processing element for storing a program and data, and at least one storage element for performing the second application of the present application Aspect or method provided in the third aspect.

In a ninth aspect, the embodiment of the present application further provides a computer storage medium, where the software program stores a software program, and the software program can implement the first aspect to the third aspect when being read and executed by one or more processors. Or a method provided by any one of the above aspects.

In a tenth aspect, the embodiment of the present application further provides a computer program product comprising instructions, when executed on a computer, causing the computer to perform the method described in the above aspects.

In an eleventh aspect, an embodiment of the present application provides a chip system, where the chip system includes a processor for supporting a terminal device or a UDM entity to implement the functions involved in the foregoing aspects. In a possible design, the chip system further comprises a memory for storing necessary program instructions and data of the terminal device or the UDM entity. The chip system can be composed of chips, and can also include chips and other discrete devices.

In the solution provided by the embodiment of the present application, in a case that the terminal device has accessed the first PLMN and is to access the second PLMN, the terminal device or the UDM entity may be configured when the terminal device accesses the two PLMNs. When the access type to which the access technology belongs is different, it is determined that the UDM entity still retains registration information of the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. Through the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the solution can ensure that two AMF entities responsible for the same terminal device can simultaneously register with the UDM entity. The method is successful, so that the terminal device frequently initiates a network registration process, reduces unnecessary signaling overhead, and improves network access performance and service performance of the terminal device.

DRAWINGS

FIG. 1 is a schematic structural diagram of a mobile communication system according to an embodiment of the present application;

2 is a flowchart of a network registration method according to an embodiment of the present application;

FIG. 3 is a flowchart of a method for registering a network according to an embodiment of the present application;

4 is a flowchart of a first network communication method according to an embodiment of the present application;

FIG. 5 is a flowchart of a second network communication method according to an embodiment of the present application;

FIG. 6 is a structural diagram of a first terminal device according to an embodiment of the present application;

FIG. 7 is a structural diagram of a first UDM entity provided by an embodiment of the present application;

FIG. 8 is a structural diagram of a second UDM entity provided by an embodiment of the present application;

FIG. 9 is a structural diagram of a second terminal device according to an embodiment of the present application;

FIG. 10 is a structural diagram of a third UDM entity provided by an embodiment of the present application.

Detailed ways

The present application provides a network communication method and device, so that two AMF entities responsible for the same terminal device can simultaneously register successfully in the UDM entity. The method and the device are based on the same inventive concept. Since the principles of the method and the device for solving the problem are similar, the implementation of the device and the method can be referred to each other, and the repeated description is not repeated.

In the solution provided by the embodiment of the present application, in a case that the terminal device has accessed the first PLMN and is to access the second PLMN, the terminal device or the UDM entity may adopt when the terminal device accesses the two PLMNs. When the access type to which the access technology belongs is different, it is determined that the UDM entity still retains registration information of the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. Through the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the solution can ensure that two AMF entities responsible for the same terminal device can simultaneously register with the UDM entity. The method is successful, so that the terminal device frequently initiates a network registration process, reduces unnecessary signaling overhead, and improves network access performance and service performance of the terminal device.

Hereinafter, some of the terms in the present application will be explained to be understood by those skilled in the art.

1), terminal equipment, also known as user equipment (UE), mobile station (MS), mobile terminal (MT), etc., is a kind of voice and / or data connection to the user Sexual equipment. For example, the terminal device includes a handheld device having a wireless connection function, an in-vehicle device, and the like. Currently, the terminal devices can be: mobile phones, tablets, laptops, PDAs, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality ( Augmented reality, AR) wireless terminal in equipment, industrial control, wireless terminal in self driving, wireless terminal in remote medical surgery, smart grid A wireless terminal, a wireless terminal in a transportation safety, a wireless terminal in a smart city, or a wireless terminal in a smart home.

2), PLMN, a mobile communication network of a certain type provided by an operator in a certain country or region. Each PLMN has a unique identifier for identifying the PLMN, and the identifiers of different PLMNs are different.

In order to distinguish between the PLMN to which the terminal device has been accessed and the PLMN to be accessed, in the present application, the first PLMN and the second PLMN are respectively named. The first PLMN is a PLMN that has been accessed by the terminal device. The number of the PLMNs that the terminal device has access to may be one or multiple, which is not limited in this application. The second PLMN is a PLMN to be accessed by the terminal device. Generally, the terminal device accesses the PLMN, and each time, the access to the PLMN is generally one for each PLMN. Therefore, in this application, only the number of the second PLMN is taken as an example. Be explained.

3) The access type can be distinguished according to the type of the radio access network. The radio access network includes two types: a 3GPP access network and a non-3GPP access network. Correspondingly, the access type includes two types: a 3GPP access type and a non-3GPP access type.

The terminal device can access the PLMN by using an access technology corresponding to the 3GPP access type. For example, the access technologies corresponding to the 3GPP access type include: a universal mobile telecommunications system (UMTS) UMTS terrestrial radio access network (UTRAN) access technology, or an evolved UTRAN (evolved- UTRAN, E-UTRAN) access technology, etc.;

The terminal device can access the PLMN through an access technology corresponding to the non-3GPP access type. For example, the access technologies corresponding to the non-3GPP access type include: a wireless local area network (WLAN) access technology, a worldwide interoperability for microwave access (WIMAX) access technology, and the like.

4) The first access type is an access type to which the first access technology is used when the terminal device accesses the first PLMN.

The number of the first PLMNs may be one, or may be multiple. When the number of the first PLMNs is multiple, the first connection that may be adopted when the terminal device accesses each first PLMN The access technology may be different. Further, the access type of each first access technology may also be different. Therefore, the number of the first access types may be two.

In addition, the terminal device can access the same PLMN through different access technologies, and the different access technologies may also belong to different access types. For example, the terminal device may access the PLMN 1 by using an E-UTRAN access technology. If the PLMN 1 is not disconnected, the terminal device may also access the PLMN 1 again by using a WLAN access technology.

In summary, the number of access types included in the first access type may be one or two, that is, the first access type includes a 3GPP access type and/or a non-3GPP access type.

5) The second access type is an access type to which the second access technology used when the terminal device accesses the second PLMN. In general, the terminal device generally uses an access technology when accessing a PLMN. Therefore, the second access type includes one access type, that is, the second access type is 3GPP access. Type or non-3GPP access type.

Since the first access type includes one or two access types, and the second access type includes one access type, the second access type and the location are involved in the present application. In the scenario in which the first access type is compared (for example, the second access type is different or the same as the first access type), the first access type includes one access type. For example, it can be done according to the following principles:

For example, when the first access type is a 3GPP access type and the second access type is a 3GPP access type, the second access type is the same as the first access type. When the first access type is a non-3GPP access type and the second access type is a non-3GPP access type, the second access type is the same as the first access type.

For another example, when the first access type is a 3GPP access type and the second access type is a non-3GPP access type, the second access type is different from the first access type. When the first access type is a non-3GPP access type, and the second access type is a 3GPP access type, the second access type is different from the first access type.

When the first access type includes two access types, the first access type and the second access type are not in a comparative relationship, but include a relationship.

For example, when the first access type includes a 3GPP access type and a non-3GPP access type, and the second access type is a 3GPP access type, it may be determined that the first access type exists and The second access type has the same access type.

6) Dual connectivity capability, which is used to indicate that the terminal device supports access to the PLMN by using access technologies of two access types at the same time. For example, the dual connectivity capability of the terminal device is set by the manufacturer of the terminal device and may not be configurable by the user.

The registration information of the AMF entity saved in the UDM may include the identifier of the AMF entity, the identifier of the PLMN accessed by the terminal device that the AMF entity is responsible for, the terminal device identifier, and the terminal device access station. At least one of the access types to which the access technology employed in the PLMN belongs.

8), "and / or", describes the association relationship of the associated object, indicating that there can be three relationships, for example, A and / or B, can mean: A exists separately, there are A and B at the same time, B exists separately Happening. The character "/" generally indicates that the contextual object is an "or" relationship.

It should be noted that the plurality of items referred to in the present application mean two or more.

In addition, it should be understood that in the description of the present application, the terms "first", "second" and the like are used only to distinguish the purpose of description, and are not to be understood as indicating or implying relative importance, nor as an indication. Or suggest the order.

The embodiments of the present application are specifically described below with reference to the accompanying drawings.

FIG. 1 shows an architecture of a possible mobile communication system to which the network communication method provided by the embodiment of the present application is applicable. Referring to FIG. 1, the mobile communication system includes a radio access network and a core network. The radio access network includes two types: a 3GPP access network 101 and a non-3GPP access network 102.

The radio access network is configured to provide the terminal device 109 with a service related to radio access. among them,

The 3GPP access network 101 may include: a universal mobile telecommunications system (UMTS) terrestrial radio access network (UTRAN), or an evolved UTRAN (evolved-UTRAN, E-UTRAN) Wait;

The non-3GPP access network 102 may include a WLAN or WIMAX network or the like.

Since the radio access network includes the above two types in the mobile communication system, the terminal device 109 can select the 3GPP access network 101, and/or the non-3GPP access network 102 A wireless access service is provided, which is not limited in this application.

In addition, the radio access network includes an access network device for communicating with the accessed terminal device 109.

The access network device in the 3GPP access network 101 may be referred to as a 3GPP access network device, or a base station, for example, a gNB, a transmission reception point (TRP), and an evolved Node B (evolved Node B, eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (for example , home evolved NodeB, or home Node B, HNB), baseband unit (BBU), etc.

The access network device in the non-3GPP access network 102 may be referred to as a non-3GPP access network device, or an access point (AP), such as: wireless fidelity (Wifi) AP, WIMAX. AP and so on.

The core network is used to connect the terminal device 109 to a data network (DN) 108 that can implement the services of the terminal device 109. Two types of network elements are included in the core network: a control plane network element and a user plane network element. The control plane network element is configured to implement functions such as session management, access and mobility management, or policy control, and the user plane network element is configured to forward user plane data of the terminal device 109.

Optionally, the control plane network element is different according to the implemented logical function, and may include, but is not limited to, the following network elements: an AMF entity 103, a session management function (SMF) entity 104, a UDM entity 105, and a non-3GPP interworking. A non-3GPP interworking function (N3IWF) entity 106, as shown.

The AMF entity 103 is configured to be responsible for the authentication of the terminal device 109 and mobility management when accessing the network, and the like;

The SMF entity 104 is responsible for session management, such as session creation, modification, deletion, and selection of user plane network elements.

The UDM entity 105 is configured to manage subscription data of the terminal device 109, registration information related to the terminal device 109, and is responsible for functions such as policy control decisions.

The N3IWF entity 106 is configured to provide an interworking function for the terminal device 109, so that the terminal device 109 can access the core network through the non-3GPP access network 102.

Optionally, the user plane network element, which is also referred to as a user plane function (UPF) entity 107, is mainly responsible for processing user plane data of the terminal device 109, such as forwarding, charging, and the like.

A data network (DN) 108 provides a service service for the terminal device 109 by performing data transmission with the terminal device 109, and the DN may be a PDN network, such as the Internet (Internet) and IP multimedia service (IP). Multi-media Service, IMS) network, etc.

In addition, in the mobile communication system, the terminal device 109, the radio access network, each network element in the core network, and the DN 108 are connected through corresponding interfaces, as shown in FIG. , will not repeat them here.

It should be noted that, the embodiment of the present application does not limit the distribution form of each functional entity in the control plane network element. Optionally, the control plane network element may also include any of the foregoing multiple network elements that may be merged. Other functional entities, for example, functional entities with both session management and policy control functions, or functional entities with three functions: session management, access and mobility management, and policy control.

In the mobile communication system shown in FIG. 1, the terminal device can complete registration of the AMF entity by the UDM entity and access the PLMN through the network registration procedure shown in FIG. 2. Referring to FIG. 2, the network registration process includes:

S201: The terminal device needs to implement a certain service or connection DN by accessing the PLMN, or send the radio resource control (radio resource control) carrying the wireless parameter and the registration request to the access network device when the terminal device is powered on. RRC) message to initiate the network registration process.

Optionally, the wireless parameter includes the terminal device identifier (such as a user permanent identifier (SUPI), or a user temporary identifier), and the identifier of the PLMN. Optionally, the wireless parameter may further include network slice select assistant information (NSSAI).

Optionally, the registration request also includes the terminal device identifier and the identifier of the PLMN.

Optionally, in the wireless parameter and the registration request, the identifier of the PLMN may be included in the terminal device identifier.

The terminal device identifier may be carried in the information sent in the subsequent step to identify that the step is performed for the terminal device.

S202: After receiving the RRC message, the access network device acquires the wireless parameter and the registration request carried in the RRC message, and the access network device selects the message according to the wireless parameter. The terminal device provides an AMF entity for mobility management.

S203: The access network device sends, to the AMF entity, an N2 message carrying an N2 parameter and the registration request. The N2 parameter includes a location of the terminal device, and an access type to which the access technology used by the terminal device belongs.

S204: After receiving the N2 message, the AMF entity acquires registration information, and sends an update location request (update location request) carrying the registration information to the UDM entity according to the registration request in the N2 message.

Optionally, the registration information includes at least one of the terminal device identifier, the identifier of the AMF entity, the identifier of the PLMN, and the access type.

S205: After receiving the update location request, the UDM entity saves the registration information.

S206: The UDM entity sends an update location response to the AMF entity to notify the AMF entity that the UMM entity successfully registers with the AMF entity.

Optionally, the update location response carries the subscription data of the terminal device. In this way, the AMF entity may save the subscription data of the terminal device after receiving the update location response.

S207: The AMF entity sends a registration accept message to the terminal device by using the access network device to notify the terminal device to successfully register to the network.

S208: The terminal device sends a registration complete message to the AMF entity by using the access network device to notify the AMF entity that the network registration process ends.

In the mobile communication system, the terminal device may complete the deregistration of the AMF entity responsible for the mobility management of the terminal device by the UDM entity through the network deregistration process shown in FIG. 3. Referring to FIG. 3, the network deregistration process includes:

S301: The UDM entity sends a cancel location request (cancel location request) carrying the terminal device identifier to the AMF entity that needs to be registered.

S302: After receiving the cancel location request, the AMF entity deletes a context of the terminal device. The context of the terminal device includes at least one of the terminal device identifier, the subscription data of the terminal device, and a registration area of the terminal device.

When the terminal device has a session connection, the AMF entity also initiates a session flow for releasing the terminal device (initiating a notification to the SMF entity responsible for the terminal device session management to trigger the SMF entity to initiate a release session process) .

S303: The AMF entity sends a cancel location response to the UDM entity to notify the UDM entity that the AMF entity can be deregistered.

S304: The UDM entity deletes the registration information of the AMF entity, and completes deregistration of the AMF entity.

It should be noted that, in the embodiment of the present application, the communication method provided by the embodiment of the present application may be completed through the foregoing process.

The embodiment of the present application provides a network communication method, which may be, but is not limited to, applied to a mobile communication system as shown in FIG. 1. In the method, the terminal device may determine, according to a logical judgment, whether the UDM entity needs to deregister the first AMF entity, where the first AMF entity is responsible for the mobility management when the terminal device accesses the accessed first PLMN. . Referring to Figure 4, the process of the method includes:

S401: The terminal device acquires a first access type to which the first access technology is used when accessing the first PLMN, and a second access type to which the second access technology is used when accessing the second PLMN.

The first PLMN is a PLMN that the terminal device has accessed, the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a 3GPP access type and/or a non- 3GPP access type, the second access type is a 3GPP access type or a non-3GPP access type.

Optionally, the terminal device may select the second PLMN by using an automatic network selection mode. The second PLMN may be: a registered PLMN (registered PLMN, RPLMN), a PLMN (equivalent PLMN, EPLMN) equivalent to the currently selected PLMN, and a global user identity module installed in the terminal device (universal Subscriber identity module, USIM) PLMN (home PLMN, HPLMN) to which the card belongs, PLMN (equivalent HPLMN, EHPLMN) equivalent to HPLMN, PLMN in the PLMN list stored in the USIM card, or saved in the USIM The PLMN in the PLMN list set by the operator in the card is not limited in this application.

Optionally, the terminal device may obtain the second access type by:

The first way:

The terminal device sends a request for carrying the location information of the terminal device to an access network discovery and selection function (ANDSF) entity in the mobile communication system;

The ANDSF entity provides the terminal device with information about an access network that can be used in the vicinity of the terminal device according to an operator policy, including an access technology used by the terminal device to access the access network, and/or Or the access type to which the access technology belongs;

The terminal device may determine the second access type according to information about an access network provided by the ANDSF entity. For example, after the terminal device determines that the terminal device accesses the access technology used by the access network, determining, according to the correspondence between the access type and the access technology included therein, the access technology belongs to Two access types.

The second way:

The terminal device performs signal measurement on a signal sent by the received 3GPP access network device and a signal sent by the non-3GPP access network device, and selects a target access network device with high signal transmission efficiency;

Determining, by the terminal device, an access technology used by the target access network device, to determine a second access type to which the access technology belongs; or determining, by the terminal device, the corresponding to the target access network device Second access type.

Optionally, the terminal device saves the second PLMN and the second access after determining the second access type when the second PLMN is to be accessed by using any one of the foregoing manners. Types of. Correspondingly, the terminal device may determine the first access type by using any one of the foregoing manners when the first PLMN is to be accessed, and save the first PLMN and the first access type. . In this way, the terminal device can read the saved first access type, and implement S401.

According to the difference in the number of access types included in the first access type, and the relationship between the first access type and the second access type, the following embodiments are included in the present application. Scene. The method provided in accordance with an embodiment of the present application may include a method performed in any of the following scenarios. The scenario 1, the scenario 2, and the scenario 3 are all in the case that the first access type includes one access type. Scenario 4 is in the case where two access types are included in the first access type.

scene one:

S402a: When the terminal device determines that the second access type is different from the first access type, sending a first registration indication to a UDM entity, where the first registration indication is used to indicate the UDM entity The registration information of the first AMF entity is reserved, and the first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN.

In the case that the terminal device accesses the same PLMN through two access types, or in the case that the terminal device accesses different PLMNs through two access types respectively, the terminal device is The UDM entity may be instructed to retain registration information of the first AMF entity.

Optionally, the terminal device may send the first registration indication to the UDM entity by:

The terminal device sends the first registration indication to the UDM entity by using the second AMF entity. The second AMF entity is responsible for mobility management when the terminal device accesses the second PLMN.

Optionally, the first registration indication sent by the second AMF entity to the UDM entity may further notify the UDM entity to register the second AMF entity.

Optionally, the terminal device may send the foregoing to the UDM entity by using a network registration process as shown in FIG. 2, where the AMF entity shown in FIG. 2 is the second AMF entity in the embodiment of the present application. First registration instruction. For example, in S201, the first registration indication may be carried in the RRC message or the registration request; in S203, the first registration indication may be carried in the N2 message or in the registration request; In S204, the first registration indication may be carried in the update location request.

In the above method, the first registration indication not only indicates that the UDM entity does not register the first AMF entity, but also triggers the UDM entity to send the second by sending the process of the first registration indication. The AMF entity is registered.

In the case of the mobile communication system, when the terminal device accesses the same PLMN through access technologies corresponding to two different access types, then the terminal device is responsible for accessing the PLMN through the 3GPP access type. The AMF entity of the mobility management may be a different AMF entity than the AMF responsible for mobility management when the terminal device accesses the PLMN through the non-3GPP access type. Therefore, the determining, by the terminal device, that the second access type is different from the first access type, instructing the UDM entity to retain registration information of the first AMF, that is, not correct Said the first AMF to register. In this way, after the UDM entity successfully registers with the second AMF entity, the UDM entity can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and the terminal device can implement simultaneous use. Two access technologies corresponding to different access types, and accessing the PLMN through two AMF entities. In addition, the solution can prevent the terminal device from frequently initiating a network registration process and reduce unnecessary signaling overhead.

Optionally, in a first possible implementation manner, before the sending, by the terminal device, the first registration indication, the terminal device further includes:

The terminal device determines that the identifier of the second PLMN is different from the identifier of the first PLMN.

In the mobile communication system, when the identifier of the first PLMN is different from the identifier of the second PLMN, and the second access type is different from the first access type, the terminal device is responsible for The AMF entity of the mobility management when accessing the PLMN through the 3GPP access type and the AMF entity responsible for the mobility management when the terminal device accesses the PLMN through the non-3GPP access type must be different AMF entities. Therefore, in the implementation, the terminal device determines that the second access type is different from the first access type, and the identifier of the second PLMN is different from the identifier of the first PLMN, The UDM entity retains registration information of the first AMF, that is, does not register with the first AMF. In this way, after the UDM entity successfully registers with the second AMF entity, the UDM entity can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and the terminal device can implement simultaneous use. Access technologies corresponding to two different access types, and accessing two PLMNs through two AMF entities respectively. In addition, the solution can prevent the terminal device from frequently initiating a network registration process and reduce unnecessary signaling overhead.

Optionally, in a second possible implementation manner, before sending the first registration indication, the terminal device further needs to determine that the following conditions are met:

The terminal device determines that the terminal device has dual connectivity capability, wherein the dual connectivity capability is used to indicate that the terminal device supports accessing a PLMN by using an access technology of two access types at the same time.

Further, the dual connectivity capability may also indicate that the terminal device supports accessing two different PLMNs by using access technologies of two access types at the same time.

The whether the terminal device has dual connectivity capability may be pre-configured. Therefore, the terminal device can acquire its own configuration information and determine whether it has dual connectivity capabilities.

If the terminal device has dual connectivity capabilities, the terminal device can access the PLMN by using access technologies of two access types at the same time. Therefore, after the terminal device determines that it has dual connectivity capability, the terminal device instructs the UDM entity not to deregister the first AMF entity, after the UDM entity registers the second AMF entity. The UDM entity may simultaneously store registration information of two AMF entities responsible for mobility management of the same terminal device, and the terminal device may implement access to the PLMN by using access technologies of two access types.

S403a: After the UDM entity receives the first registration indication from the terminal device, the UDM entity reserves the registration information of the first AMF entity according to the first registration indication.

Optionally, the first registration indication sent by the terminal device to the UDM entity by using the second AMF entity may further notify the UDM entity to register the second AMF entity. Therefore, after receiving the first registration indication sent by the second AMF entity, the UDM entity may further register the second AMF entity (save registration information of the second AMF entity).

Optionally, in the mobile communication system, the terminal device may adopt the foregoing second implementation manner, that is, when the terminal device determines to have the dual connectivity capability, and then sends the first registration indication, the UDM entity is receiving. After the first registration indication, the registration information of the first AMF entity may be directly retained without determining whether the terminal device has dual connectivity capability.

Optionally, in the mobile communication system, the terminal device may not adopt the foregoing second implementation manner, that is, the terminal device does not need to determine whether it has dual connectivity capability before sending the first registration indication, in this case, The UDM entity further includes the following steps before performing the S402a to retain the registration information of the first AMF entity according to the first registration indication:

The UDM entity determines that the terminal device has dual connectivity capabilities.

For example, the terminal device may send the connection capability indication information to the UDM entity by using the network registration process as shown in FIG. 2 (the AMF entity shown in FIG. 2 is the second AMF entity in the embodiment of the present application). The connection capability indication information is used to indicate whether the terminal device has dual connectivity capabilities. For example, in S201, the connection capability indication information may be carried in the RRC message or the registration request. In S203, the connection capability indication information may be carried in the N2 message or in the registration request. In S204, the connection capability indication information may be carried in the update location request. After obtaining the connection capability indication information sent by the terminal device, the UDM entity may determine, according to the connection capability indication information, whether the terminal device has dual connectivity capability.

In this way, the UDM entity may not only deregister the first AMF entity but also the mobile device when the terminal device accesses the second PLMN, if the terminal device has the dual connectivity capability. The second AMF entity of the sexual management registers to implement dual registration of the first AMF entity and the second AMF entity.

In the scenario of scenario 1 of the embodiment of the present application, in a case that the terminal device has accessed the first PLMN and is to access the second PLMN, the terminal device may be used when the terminal device accesses the two PLMNs. When the access type to which the access technology belongs is different, it is determined that the UDM entity still retains registration information of the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. With the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the terminal device determines when accessing the PLMN through access technologies corresponding to two different access types. The two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, so that the terminal device can implement the access technology corresponding to two different access types at the same time, and through two AMF entities. Access to the PLMN. In addition, the solution can prevent the terminal device from frequently initiating a network registration process, reduce unnecessary signaling overhead, and improve network access performance and service performance of the terminal device.

Scene 2:

S402b: Send a second registration indication to the UDM entity when the terminal device determines that at least one of the following conditions is met. The second registration indication is used to instruct the UDM entity to perform deregistration on the first AMF entity.

Optionally, the condition includes at least one of the following two:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type.

Optionally, the conditions include the following three:

Sending a second registration indication to the UDM entity when the terminal device determines at least one of the following:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The identifier of the second PLMN is the same as the identifier of the first PLMN.

When the terminal device does not have the dual connectivity capability, even if the terminal device sends the first registration indication to the UDM entity, the terminal device can only access the latest requested second PLMN, such that And the registration information of the first AMF entity retained by the UDM entity, and the context of the terminal device maintained in the first AMF entity occupying a storage space of the UDM entity and the first AMF entity, And the first AMF entity needs to maintain the context of the terminal device. Therefore, when the terminal device does not have the dual connectivity capability, the terminal device may release the second AMF entity in the UDM entity by sending the second registration indication to the UDM entity. The storage space occupied by the registration information and the storage space occupied by the context of the terminal device in the first AMF entity are avoided, thereby avoiding waste of storage space in the UDM entity and the first AMF entity, and avoiding The signaling overhead brought by the first AMF entity to the context maintenance of the terminal device.

S403b: After receiving the second registration indication from the terminal device, the UDM entity performs deregistration on the first AMF entity.

Through the above steps, the UDM entity may deregister the first AMF entity, that is, delete the registration information of the first AMF entity in the UDM entity, and therefore, the solution may release the UDM entity The storage space occupied by the registration information of the first AMF entity; in addition, the first AMF entity deletes the context of the terminal device correspondingly during the process of deregistering the first AMF entity, therefore, The solution may further release the storage space occupied by the context of the terminal device in the first AMF entity. In summary, the method can avoid the waste of the storage space in the UDM entity and the first AMF entity, and avoid the signaling overhead caused by the first AMF entity to the context maintenance of the terminal device. .

Optionally, the second registration indication is further configured to trigger the UMM entity to notify the first SMF entity to release the session of the terminal device, where the first SMF entity is responsible for the terminal device accessing the first Session management at PLMN.

Optionally, after receiving the second registration indication, the UDM entity sends a session release notification message to the first SMF entity to notify the first SMF entity to release the session of the terminal device.

In the scenario of the scenario 2 of the embodiment of the present application, in a case that the terminal device has accessed the first PLMN and is to access the second PLMN, the terminal device determines that the condition for sending the first registration indication is not currently met, then The UDM entity sends a second registration indication to notify the UDM entity to deregister the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN.

It should be noted that, in scenario 1 and scenario 2, the UDM entity may determine whether the terminal device has dual connectivity capability by using the connection capability indication information reported by the terminal device.

Scene 3:

S402c: When the terminal device determines that the second access type is different from the first access type, and sends a second registration indication to the UDM entity.

Optionally, the terminal device may determine whether to send the second registration indication to the UDM entity by:

Manner 1: The terminal device determines a priority of the first PLMN; when the priority of the first PLMN is lower than a set PLMN priority threshold, the terminal device determines to send the first to the UDM entity Second registration instruction;

Manner 2: the terminal device determines a priority of a session established when the terminal device accesses the first PLMN; when the priority of the session is lower than a set session priority threshold, the terminal device determines to Sending, by the UDM entity, the second registration indication;

Manner 3: the terminal device determines a priority of the service established when the terminal device accesses the first PLMN; when the priority of the service is lower than a set service priority threshold, the terminal device determines to The UDM entity sends the second registration indication.

Through the foregoing method, the terminal device may determine, according to the preference of the terminal device, whether to send the second registration indication to the UDM entity. In this way, when the terminal device adopts the solution provided by the foregoing manner, the terminal device can ensure that the high priority PLMN accesses normally by comparing the priority of the PLMN with the PLMN priority threshold; when the terminal device adopts When the solution provided by the foregoing mode 2 is used, the terminal device can ensure that the high-priority session is normally performed by comparing the priority of the session with the session priority threshold; The terminal device can ensure that the high-priority service runs normally by comparing the priority of the service with the service priority threshold.

S403c: After receiving the second registration indication from the terminal device, the UDM entity performs deregistration on the first AMF entity.

Optionally, in scenario 2 and scenario 3, the terminal device may send the second registration indication to the UDM entity by using the second AMF entity. The second registration indication may further notify the UDM entity to register the second AMF entity. In this way, after receiving the second registration indication, the UDM entity may not only register the first AMF entity but also register the second AMF entity.

Optionally, the function and the operation of the second registration indication in the scenario 2 are similar. In addition, the second registration indication in the scenario 3 may further be used to trigger the UMM entity to notify the first SMF entity. Release the session of the terminal device.

It should be noted that, in the scenario 2 and the scenario 3, the terminal device may also pass the network registration process as shown in FIG. 2 (the AMF entity shown in FIG. 2 is the second AMF entity in this embodiment). And transmitting the second registration indication to the UDM entity. For example, in S201, the second registration indication may be carried in the RRC message or the registration request; in S203, the second registration indication may be carried in the N2 message, or in the registration request In S204, the second registration indication may be carried in the update location request.

In addition, the second registration indication may not only indicate that the UDM entity deregisters the first AMF entity, but also triggers the UDM entity to send the The second AMF entity registers.

In addition, it should be noted that, in the scenario 2 and the scenario 3 of the embodiment of the present application, the UDM entity may perform a registration process through the network shown in FIG. 3 (the AMF entity shown in FIG. 3 is the embodiment of the present application. For the first AMF entity, the de-registration of the first AMF entity is completed. For the specific process, refer to the description of the steps in FIG. 3, and details are not described herein again.

Scene 4:

S402d: When the terminal device determines that the same target access type as the second access type exists in the first access type, sending a third registration indication to the UDM entity, where the The third registration indication is used to instruct the UDM entity to perform deregistration on the target AMF entity, where the target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN in the first PLMN, where the target PLMN is The terminal device adopts a PLMN accessed by an access technology belonging to the target access type.

Optionally, the third registration indication may further notify the UDM entity to register the second AMF entity. In this way, after receiving the third registration indication, the UDM entity may not only deregister the target AMF entity, but also register the second AMF entity. Optionally, the terminal device may send the third registration indication to the UDM entity by using the second AMF entity.

Optionally, the terminal device may also send the device to the UDM entity by using a network registration process as shown in FIG. 2 (the AMF entity shown in FIG. 2 is the second AMF entity in this embodiment). The third registration instruction is described. For example, in S201, the third registration indication may be carried in the RRC message or the registration request; in S203, the third registration indication may be carried in the N2 message, or in the registration request In S204, the third registration indication may be carried in the update location request.

In the above method, the third registration indication not only indicates that the UDM entity deregisters the target AMF entity, but also triggers the UDM entity to send the second AMF by sending the process of the third registration indication. Entity registration.

For example, when the first access type includes a 3GPP access type and a non-3GPP access type, and the second access type includes a 3GPP access type, the target PLMN is described in the first PLMN. The terminal device adopts a PLMN accessed by an access technology belonging to the 3GPP access type, and the target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN.

S403d: After receiving the third registration indication from the terminal device, the UDM entity performs deregistration on the target AMF entity.

Optionally, the third registration indication is further used to trigger the UDM entity to notify the target SMF entity to release the session of the terminal device. The target SMF entity is responsible for session management when the terminal device accesses the target PLMN.

Optionally, the UDM entity may adopt a network deregistration process as shown in FIG. 3 (where the AMF entity shown in FIG. 3 is the target AMF entity in the embodiment of the present application), and complete the target AMF entity. To register, the specific process can be referred to the above description of each step in FIG. 3, and details are not described herein again.

In the scenario of the fourth scenario of the embodiment of the present application, when the terminal device has accessed the PLMN by using the access technology corresponding to the two access types, if the terminal device needs to continue to adopt one of the access types, The access technology accesses the PLMN, and the terminal device may notify the UDM entity to deregister the target AMF entity by using the third registration indication. In this way, after the UDM entity successfully registers with the second AMF entity, the UDM entity can ensure that the terminal device can access the PLMN by using the access technologies of the two access types at the same time, that is, in the UDM entity. The registration information of the two AMF entities responsible for the mobility management when the terminal device accesses the PLMN through the access technologies of the two access types is stored. Therefore, the solution can ensure that two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, thereby preventing the terminal device from frequently initiating a network registration process, reducing unnecessary signaling overhead, and improving the terminal. Network access performance and service performance of the device.

The embodiment of the present application provides another network communication method, which may be, but is not limited to, applied to the mobile communication system shown in FIG. 1. In the method, the UDM entity may determine whether it needs to deregister the first AMF entity according to a logical judgment, and the first AMF entity is responsible for mobility management when the terminal device accesses the accessed first PLMN. Referring to Figure 5, the process of the method includes:

S501: The UDM entity acquires a first access type to which the first access technology is used when the terminal device accesses the first PLMN, and a second access type to which the second access technology is used when accessing the second PLMN.

Optionally, the UDM entity may obtain the second access type by, but not limited to,:

The first mode: the UDM entity may receive the second access type sent by the terminal device, where the second access type is determined by the terminal device. For example, the terminal device may acquire the second access type in two manners in the embodiment shown in FIG. Optionally, the terminal device may send the second access type to the UDM entity by using S201 to S204 in the network registration process as shown in FIG. 2 .

The second mode: the UDM entity may receive the second access type sent by the second AMF entity, where the second AMF entity is responsible for mobility management when the terminal device accesses the second PLMN . For example, the second AMF entity may send the second access type in the update location request to the UDM entity when in the network registration procedure S204 shown in FIG. 2 .

Optionally, in the second manner, the second AMF may determine a second access technology that is used when the terminal device accesses the second PLMN, and determine the second access The second access type to which the technology belongs.

Optionally, the UDM entity saves the second PLMN and the second access after determining, by the second access mode, that the second access type is determined by the UDM entity. Types of. Correspondingly, when the terminal device is to access the first PLMN, the UDM entity may determine the first access type by using any one of the foregoing manners, and save the first PLMN and the first An access type. In this way, the UDM entity can read the saved first access type, and implement S501.

scene one:

S502a: When the UDM entity determines that the terminal device has dual connectivity capability, and the second access type is different from the first access type, retaining registration of the first access and mobility management function AMF entity Information, wherein the first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN, and the dual connectivity capability is used to indicate that the terminal device supports simultaneous access of two access types. The incoming technology accesses the PLMN.

In the case that the terminal device accesses the same PLMN through two access types, or in the case that the terminal device accesses different PLMNs through two access types respectively, the UDM entity may The registration information of the first AMF entity is retained.

If the terminal device has dual connectivity capabilities, the terminal device can access the PLMN by using access technologies of two access types at the same time. Therefore, the UDM entity does not deregister the first AMF entity after determining that the terminal device has the dual connectivity capability, and after the UDM entity registers the second AMF entity, The UDM entity may simultaneously store registration information of two AMF entities responsible for mobility management of the same terminal device, and the terminal device may implement access technologies using two access types to access the PLMN.

In the case of the mobile communication system, when the terminal device accesses the same PLMN through access technologies corresponding to two different access types, then the terminal device is responsible for accessing the PLMN through the 3GPP access type. The AMF entity of the mobility management may be a different AMF entity than the AMF responsible for mobility management when the terminal device accesses the PLMN through the non-3GPP access type. Therefore, by the step S502a, the UDM entity reserves the first AMF entity if it is determined that the second access type is different from the first access type, and the terminal device has dual connectivity capabilities. The registration information, ie, does not register for the first AMF. In this way, after the UDM entity successfully registers with the second AMF entity, the UDM entity can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and the terminal device can implement simultaneous use. Two access technologies corresponding to different access types, and accessing the PLMN through two AMF entities. In addition, the solution can prevent the terminal device from frequently initiating a network registration process and reduce unnecessary signaling overhead.

In a possible implementation, before the UDM entity retains the registration information of the first AMF entity, the method further includes:

The UDM entity determines that the identity of the second PLMN is different from the identity of the first PLMN.

In the mobile communication system, when the identifier of the first PLMN is different from the identifier of the second PLMN, and the second access type is different from the first access type, the terminal device is responsible for The AMF entity of the mobility management when accessing the PLMN through the 3GPP access type and the AMF entity responsible for the mobility management when the terminal device accesses the PLMN through the non-3GPP access type must be different AMF entities. Therefore, the UDM entity determines that the second access type is different from the first access type, and the identifier of the second PLMN is different from the identifier of the first PLMN, and the terminal is In the case where the device has dual connectivity capabilities, the registration information of the first AMF entity is retained, ie, the first AMF is not registered. In this way, after the UDM entity successfully registers with the second AMF entity, the UDM entity can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and the terminal device can implement simultaneous use. Access technologies corresponding to two different access types, and accessing two PLMNs through two AMF entities respectively. In addition, the solution can prevent the terminal device from frequently initiating a network registration process and reduce unnecessary signaling overhead.

In the above manner, the UDM entity may obtain the identifier of the second PLMN by:

The first mode: the UDM entity may receive the identifier of the second PLMN sent by the terminal device. Optionally, the terminal device may send the identifier of the second PLMN to the UDM entity by using S201 to S204 in the network registration process shown in FIG. 2 .

The second mode: the UDM entity may receive the identifier of the second PLMN sent by the second AMF entity, for example, the second AMF entity may be in the network registration process S204 shown in FIG. The identifier of the second PLMN is carried in the update location request and sent to the UDM entity.

Optionally, the UDM entity saves the identifier of the second PLMN after determining the identifier of the second PLMN when the terminal device is to access the second PLMN by using any one of the foregoing manners. Correspondingly, when the terminal device is to be accessed by the first PLMN, the UDM entity may determine the identifier of the first PLMN by using any one of the foregoing manners, and save the identifier of the first PLMN. In this way, the UDM entity can read the saved identifier of the first PLMN, and obtain the identifier of the first PLMN.

In the scenario of scenario 1 of the embodiment of the present application, in a case that the terminal device has accessed the first PLMN and is to access the second PLMN, the UDM entity may determine that the terminal device has dual connectivity capability, and When the access type of the access technology used by the terminal device to access the two PLMNs is different, it is determined that the UDM entity still retains the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. Registration information. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. With the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the UDM entity determines that the terminal device has dual connectivity capability, and the terminal device passes When the access technologies corresponding to the two different access types are connected to the PLMN, the two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, so that the terminal device can implement two different simultaneous uses. An access technology corresponding to the access type, and accessing the PLMN through two AMF entities. In addition, the method can prevent the terminal device from frequently initiating a network registration process, reduce unnecessary signaling overhead, and improve network access performance and service performance of the terminal device.

Scene 2:

S502b: Deregister the first AMF entity when the UDM entity determines that any of the following conditions are met.

Optionally, the condition includes at least one of the following two:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type.

Optionally, the condition includes at least three of the following:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

When the terminal device does not have the dual connectivity capability, even if the UDM entity retains the registration information of the first AMF entity, the terminal device can only access the newly requested second PLMN, and thus, The registration information of the first AMF entity reserved by the UDM entity, and the context of the terminal device maintained in the first AMF entity occupying a storage space of the UDM entity and the first AMF entity, and The first AMF entity needs to maintain the context of the terminal device. Therefore, the solution may further deregister the first AMF entity when the terminal device does not have the dual connectivity capability, and release the registration information occupied by the first AMF entity in the UDM entity. The storage space, and the storage space occupied by the context of the terminal device in the first AMF entity, avoiding waste of storage space in the UDM entity and the first AMF entity, and avoiding the foregoing The signaling overhead brought by an AMF entity to the context maintenance of the terminal device.

In the solution of the scenario 2 of the embodiment of the present application, in a case that the terminal device has accessed the first PLMN and is to access the second PLMN, the UDM entity determines that the condition for retaining the registration information of the first AMF entity is not currently met. The UDM entity then deregisters the first AMF entity.

It should be noted that, in scenario 1 and scenario 2, the UDM entity may determine whether the terminal device has dual connectivity capability by using the connection capability indication information reported by the terminal device. For example, the terminal device may send the connection capability indication information to the UDM entity by using the network registration process as shown in FIG. 2 (the AMF entity shown in FIG. 2 is the second AMF entity in the embodiment of the present application). The connection capability indication information is used to indicate whether the terminal device has dual connectivity capabilities. For example, in S201, the connection capability indication information may be carried in the RRC message or the registration request. In S203, the connection capability indication information may be carried in the N2 message or in the registration request. In S204, the connection capability indication information may be carried in the update location request. After obtaining the connection capability indication information sent by the terminal device, the UDM entity may determine, according to the connection capability indication information, whether the terminal device has dual connectivity capability.

Scene 3:

S502c: When the UDM entity determines that the identifier of the first PLMN is different from the identifier of the second PLMN, and the first access type is different from the second access type, determining the first AMF. The entity needs to register and deregister the first AMF entity.

Manner 1: The UDM entity determines a priority of the first PLMN; when the priority of the first PLMN is lower than a set PLMN priority threshold, the UDM determines that the first AMF entity needs to be registered;

Manner 2: the UDM entity determines a priority of a session established when the terminal device accesses the first PLMN; when the priority of the session is lower than a set session priority threshold, the UDM determines the The first AMF entity needs to register;

Manner 3: the UDM entity determines a priority of the service established when the terminal device accesses the first PLMN; when the priority of the service is lower than a set service priority threshold, the UDM determines the The first AMF entity needs to register.

Through the above method, the UDM entity can determine whether the first AMF entity needs to be registered according to the preference. In this way, when the UDM entity adopts the solution provided by the foregoing mode 1, the UDM entity can ensure that the high priority PLMN accesses normally by comparing the priority of the PLMN with the PLMN priority threshold; when the UDM entity adopts In the solution provided by the foregoing mode 2, the UDM entity can ensure that the high-priority session is performed normally by comparing the priority of the session with the session priority threshold; when the UDM entity adopts the solution provided by the foregoing manner 3, The UDM entity can ensure that the high-priority service works normally by comparing the priority of the service with the service priority threshold.

Optionally, in scenario 2 and scenario 3 of the embodiment of the present application, in a case where the UDM entity determines to deregister the first AMF entity, the UDM entity may further notify the first SMF entity to release the location. The session of the terminal device, wherein the first SMF is responsible for session management when the terminal device accesses the first PLMN. For example, the UDM entity sends a session release notification message to the first SMF entity to notify the first SMF entity to release the session of the terminal device.

Scene 4:

S502d: When the UDM entity determines that there is a target access type that is the same as the second access type in the first access type, deregistering the target AMF entity.

The target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN in the first PLMN, and the target PLMN adopts an access technology belonging to the target access type for the terminal device. Access to the PLMN.

Optionally, after determining that the target AMF entity is deregistered, the UDM entity notifies the target SMF entity to release the session of the terminal device, where the target SMF entity is responsible for accessing the target device by the terminal device. Session management at PLMN.

In the scenario of the fourth scenario of the embodiment of the present application, when the terminal device has accessed the PLMN by using the access technology corresponding to the two access types, if the terminal device needs to continue to adopt one of the access types, The access technology accesses the PLMN, and the UDM entity deregisters the target AMF entity. In this way, after the UDM entity successfully registers with the second AMF entity, the UDM entity can ensure that the terminal device can access the PLMN by using the access technologies of the two access types at the same time, that is, the UDM is saved. There are registration information of two AMF entities responsible for mobility management when the terminal device accesses the PLMN through two access type access technologies. Therefore, the solution can ensure that two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, thereby preventing the terminal device from frequently initiating a network registration process, reducing unnecessary signaling overhead, and improving the terminal. Network access performance and service performance of the device.

Based on the above embodiment, the present application further provides a terminal device, where the terminal device is used to implement the network communication method shown in FIG. 4, and the method steps performed by the terminal device in the method may be performed. Referring to FIG. 6, the terminal device 600 includes: an obtaining unit 601 and a processing unit 602, where

The obtaining unit 601 is configured to acquire a first access type to which the first access technology is used when accessing the first PLMN, and a second access type to which the second access technology is used when accessing the second PLMN, The first PLMN is a PLMN that the terminal device 600 has accessed, and the second PLMN is a PLMN to be accessed by the terminal device 600, and the first access type is a 3GPP access type and/or Or a non-3GPP access type, where the second access type is a 3GPP access type or a non-3GPP access type;

The processing unit 602 is configured to: when determining that the second access type is different from the first access type, send a first registration indication to the UDM entity, where the first registration indication is used to indicate the UDM entity The registration information of the first access and mobility management function AMF entity is reserved, and the first AMF entity is responsible for mobility management when the terminal device 600 accesses the first PLMN.

Optionally, the processing unit 602 is further configured to:

Before transmitting the first registration indication to the UDM entity, determining that the identifier of the second PLMN is different from the identifier of the first PLMN.

Optionally, the processing unit 602 is further configured to:

Determining that the terminal device 600 has dual connectivity capability before transmitting the first registration indication to the UDM entity, wherein the dual connectivity capability is used to indicate that the terminal device 600 supports simultaneous use of two access types. The access technology accesses the PLMN.

Optionally, the processing unit 602 is further configured to:

Sending a second registration indication to the UDM entity when at least one of the following is determined:

The terminal device 600 does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The second registration indication is used to indicate that the UDM entity performs deregistration on the first AMF entity, where the dual connectivity capability is used to indicate that the terminal device 600 supports access by using two access types at the same time. Technology access to the PLMN.

Optionally, the processing unit 602 is further configured to:

The terminal device 600 does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The identifier of the second PLMN is the same as the identifier of the first PLMN;

Optionally, the second registration indication is further used to trigger the UDM entity to notify the first session management function SMF entity to release the session of the terminal device 600, where the first SMF entity is responsible for receiving the terminal device 600. Session management when entering the first PLMN.

Optionally, the processing unit 602 is further configured to:

When it is determined that the same target access type as the second access type exists in the first access type, sending a third registration indication to the UDM entity, where the third registration indication is used to indicate Deleting, by the UDM entity, a target AMF entity, where the target AMF entity is responsible for mobility management when the terminal device 600 accesses a target PLMN in the first PLMN, where the target PLMN is the terminal device 600 A PLMN accessed by an access technology belonging to the target access type.

The embodiment of the present application provides a terminal device, where the terminal device can access the two PLMNs when the terminal device accesses the first PLMN and is to access the second PLMN. When the access type to which the access technology belongs is different, it is determined that the UDM entity still retains registration information of the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. With the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the terminal device determines when accessing the PLMN through access technologies corresponding to two different access types. The two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, so that the terminal device can implement the access technology corresponding to two different access types at the same time, and through two AMF entities. Access to the PLMN. In addition, the solution can prevent the terminal device from frequently initiating a network registration process, reduce unnecessary signaling overhead, and improve network access performance and service performance of the terminal device.

Based on the above embodiments, the present application further provides a UDM entity, which is used to implement the network communication method shown in FIG. 4, and may perform the method steps performed by the UDM entity in the method. Referring to FIG. 7, the UDM entity 700 includes: a receiving unit 701 and a processing unit 702, where

The receiving unit 701 is configured to receive, by the terminal device, a first registration indication, where the first registration indication is used to instruct the UDM entity 700 to retain registration information of the first access and mobility management function AMF entity, where An AMF entity is responsible for mobility management when the terminal device accesses the first PLMN, and the first PLMN is a PLMN that the terminal device has accessed;

The processing unit 702 is configured to reserve registration information of the first AMF entity according to the first registration indication.

Optionally, the processing unit 702 is further configured to:

Before the registration information of the second AMF entity is retained according to the first registration indication, determining that the terminal device has dual connectivity capability, wherein the dual connectivity capability is used to indicate that the terminal device supports two types of simultaneous use. The access type access technology accesses the PLMN.

Optionally, the receiving unit 701 is further configured to receive a second registration indication sent by the terminal device, where the second registration indication is used to instruct the UMM entity 700 to perform the first AMF entity. registered;

The processing unit 702 is further configured to perform deregistration on the first AMF entity according to the second registration indication.

Optionally, the receiving unit 701 is further configured to receive a third registration indication sent by the terminal device;

The third registration indication is used to instruct the UDM entity 700 to perform deregistration on the target AMF entity, and the target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN in the first PLMN. The target PLMN is a PLMN that is accessed by the access device that belongs to the target access type, and the target access type is the same access as the second access type in the first access type. a type, the first access type is an access type to which the access technology used by the terminal device to access the first PLMN, and the second access type is the terminal device accessing the The access type to which the access technology is used in the second PLMN, the second PLMN is the PLMN to be accessed by the terminal device, and the first access type is a 3GPP access type or a non-3GPP access type. The second access type is a 3GPP access type or a non-3GPP access type;

The processing unit 702 is further configured to perform deregistration on the target AMF entity according to the third registration indication.

The embodiment of the present application provides a UDM entity, where the terminal device can access the two PLMNs when the terminal device accesses the first PLMN and the second PLMN is to be accessed. When the access type to which the access technology belongs is different, it is determined that the UDM entity still retains registration information of the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN, and the UDM entity receives the After the first registration indication, the registration information of the first AMF entity is retained. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. With the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the terminal device determines when accessing the PLMN through access technologies corresponding to two different access types. The two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, so that the terminal device can implement the access technology corresponding to two different access types at the same time, and through two AMF entities. Access to the PLMN. In addition, the solution can prevent the terminal device from frequently initiating a network registration process, reduce unnecessary signaling overhead, and improve network access performance and service performance of the terminal device.

Based on the above embodiment, the present application further provides a UDM entity, which is used to implement the network communication method shown in FIG. 5, and may perform the method steps performed by the UDM entity in the method. Referring to FIG. 8, the UDM entity 800 includes: an obtaining unit 801 and a processing unit 802, where

The obtaining unit 801 is configured to acquire a first access type to which the first access technology that is used when the terminal device accesses the first public land mobile network (PLMN), and a second access technology that is used when accessing the second PLMN a second access type, wherein the first PLMN is a PLMN to which the terminal device has been accessed, the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a third Acting as a 3GPP access type and/or a non-3GPP access type, the second access type being a 3GPP access type or a non-3GPP access type;

The processing unit 802 is configured to reserve the registration of the first access and mobility management function AMF entity when determining that the terminal device has dual connectivity capability, and the second access type is different from the first access type Information, wherein the first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN, and the dual connectivity capability is used to indicate that the terminal device supports simultaneous access of two access types. The incoming technology accesses the PLMN.

Optionally, the processing unit 802 is further configured to:

Before retaining the registration information of the first AMF entity, determining that the identifier of the second PLMN is different from the identifier of the first PLMN.

Optionally, the processing unit 802 is further configured to:

Deregistering the first AMF entity when at least one of the following is determined:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type.

Optionally, the processing unit 802 is further configured to:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

Optionally, the processing unit 802 is further configured to:

Notifying the first session management function that the SMF entity releases the session of the terminal device, wherein the first SMF is responsible for session management when the terminal device accesses the first PLMN.

Optionally, the processing unit 802 is further configured to:

Determining to de-register the target AMF entity when it is determined that the same target access type as the second access type exists in the first access type;

An embodiment of the present application provides a UDM entity, where the UDM entity can determine that the terminal device has dual connectivity capability, and the terminal device has access to the first PLMN and the second PLMN is to be accessed. When the access type of the access technology used by the terminal device to access the two PLMNs is different, it is determined that the UDM entity still retains the first AMF entity responsible for mobility management when the terminal device accesses the first PLMN. Registration information. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. With the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the UDM entity determines that the terminal device has dual connectivity capability, and the terminal device passes When the access technologies corresponding to the two different access types are connected to the PLMN, the two AMF entities responsible for the same terminal device can be successfully registered in the UDM entity at the same time, so that the terminal device can implement two different simultaneous uses. An access technology corresponding to the access type, and accessing the PLMN through two AMF entities. In addition, the method can prevent the terminal device from frequently initiating a network registration process, reduce unnecessary signaling overhead, and improve network access performance and service performance of the terminal device.

It should be noted that the division of the modules in the embodiment of the present application is schematic, and is only a logical function division. In actual implementation, there may be another division manner. In addition, each functional unit in each embodiment of the present application may be used. It can be integrated in one processing unit, or it can exist physically alone, or two or more units can be integrated in one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application, in essence or the contribution to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium. A number of instructions are included to cause a computer device (which may be a personal computer, server, or network device, etc.) or a processor to perform all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like, which can store program codes. .

Based on the above embodiment, the embodiment of the present application further provides a terminal device, which is applied to the mobile communication system shown in FIG. 1 and is used to implement the network communication method shown in FIG. The function of the terminal device 600 shown in 6. Referring to FIG. 9, the terminal device 900 includes a transceiver 901, a processor 902, and a memory 903. The transceiver 901, the processor 902, and the memory 903 are connected to each other.

Optionally, the transceiver 901, the processor 902, and the memory 903 are connected to each other by a bus 904. The bus 904 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is shown in Figure 9, but it does not mean that there is only one bus or one type of bus.

The transceiver 901 is configured to receive and transmit data to implement communication with other devices in the mobile communication system.

The processor 902 is configured to implement the network communication method provided by the embodiment shown in FIG. 4 . For details, refer to the description in the foregoing embodiment, and details are not described herein again.

The memory 903 is configured to store program instructions and the like. In particular, program instructions may include program code, the program code including computer operating instructions. The memory 903 may include a random access memory (RAM), and may also include a non-volatile memory such as at least one disk storage. The processor 902 executes the program instructions stored in the memory 903 to implement the above functions, thereby implementing the network communication method provided by the foregoing embodiments.

Based on the above embodiment, the embodiment of the present application further provides a UDM entity, where the UDM entity is applied to the mobile communication system shown in FIG. 1 for implementing the network communication method as shown in FIG. 4 or FIG. There is a function of the UDM entity 600 as shown in FIG. 6, or the UDM entity 700 described in FIG. Referring to FIG. 10, the UDM entity 1000 includes a communication interface 1001, a processor 1002, and a memory 1003. The communication interface 1001, the processor 1002, and the memory 1003 are connected to each other.

Optionally, the communication interface 1001, the processor 1002, and the memory 1003 are connected to each other through a bus 1004. The bus 1004 may be a PCI bus or an EISA bus or the like. The bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is shown in FIG. 10, but it does not mean that there is only one bus or one type of bus.

The communication interface 1001 is configured to receive and transmit data to implement communication with other devices in the mobile communication system.

The processor 1002 is configured to implement the network communication method provided in the embodiment shown in FIG. 4 or FIG. 5 . For details, refer to the description in the foregoing embodiment, and details are not described herein again.

The memory 1003 is configured to store program instructions and the like. In particular, program instructions may include program code, the program code including computer operating instructions. The memory 1003 may include RAM and may also include non-volatile memory, such as at least one disk storage. The processor 1002 executes the program instructions stored in the memory 1003 to implement the above functions, thereby implementing the network communication method provided by the above embodiments.

In summary, the embodiment of the present application provides a network communication method and device, in which the terminal device or UDM is in the case that the terminal device has accessed the first PLMN and is to access the second PLMN. The entity may determine that the UDM entity remains responsible for mobility management when the terminal device accesses the first PLMN when the access technology used by the access device to access the two PLMNs is different. Registration information of the first AMF entity. In this way, the UDM entity may not only register the second AMF entity responsible for mobility management when the terminal device accesses the second PLMN, but may also not deregister the first AMF entity, thereby implementing the Dual registration of the first AMF entity and the second AMF entity. Through the above solution, the UDM can simultaneously save registration information of two AMF entities responsible for mobility management of the same terminal device, and therefore, the solution can ensure that two AMF entities responsible for the same terminal device can simultaneously register with the UDM entity. The method is successful, so that the terminal device frequently initiates a network registration process, reduces unnecessary signaling overhead, and improves network access performance and service performance of the terminal device.

Those skilled in the art will appreciate that embodiments of the present application can be provided as a method, system, or computer program product. Thus, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment in combination of software and hardware. Moreover, the application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) including computer usable program code.

The present application is described with reference to flowchart illustrations and/or block diagrams of the method, apparatus (system), and computer program product according to the present application. It will be understood that each flow and/or block of the flowchart illustrations and/or FIG. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine for the execution of instructions for execution by a processor of a computer or other programmable data processing device. Means for implementing the functions specified in one or more of the flow or in a block or blocks of the flow chart.

The computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device. The apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.

These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

It will be apparent to those skilled in the art that various modifications and changes can be made in the present application without departing from the spirit and scope of the application. Thus, it is intended that the present invention cover the modifications and variations of the present invention.

Claims

A network communication method, comprising:

The first access type to which the first access technology belongs when accessing the first public land mobile network PLMN, and the second access type to which the second access technology is used when accessing the second PLMN, The first PLMN is a PLMN that the terminal device has accessed, and the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a 3GPP partner 3GPP connection. Incoming type and/or non-3GPP access type, the second access type being a 3GPP access type or a non-3GPP access type;

When the terminal device determines that the second access type is different from the first access type, sending a first registration indication to the unified data management UDM entity, where the first registration indication is used to indicate the UDM The entity retains registration information of the first access and mobility management function AMF entity, and the first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN.
The method of claim 1, wherein before the terminal device sends the first registration indication to the UDM entity, the method further includes:

The terminal device determines that the identifier of the second PLMN is different from the identifier of the first PLMN.
The method according to claim 1 or 2, further comprising: before the sending, by the terminal device, the first registration indication to the UDM entity,

The terminal device determines that the terminal device has dual connectivity capability, wherein the dual connectivity capability is used to indicate that the terminal device supports accessing a PLMN by using an access technology of two access types at the same time.
The method of claim 1 wherein the method further comprises:

Sending a second registration indication to the UDM entity when the terminal device determines at least one of the following:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The second registration indication is used to indicate that the UDM entity performs deregistration on the first AMF entity, where the dual connectivity capability is used to indicate that the terminal device supports access technologies that use two access types at the same time. Access to the PLMN.
The method of claim 2, wherein the method further comprises:

Sending a second registration indication to the UDM entity when the terminal device determines at least one of the following:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The identifier of the second PLMN is the same as the identifier of the first PLMN;

The second registration indication is used to indicate that the UDM entity performs deregistration on the first AMF entity, where the dual connectivity capability is used to indicate that the terminal device supports access technologies that use two access types at the same time. Access to the PLMN.
The method of claim 4 or 5, wherein the second registration indication is further configured to trigger the UDM entity to notify the first session management function SMF entity to release the session of the terminal device, where the An SMF entity is responsible for session management when the terminal device accesses the first PLMN.
The method of any of claims 1-6, wherein the method further comprises:

When the terminal device determines that there is a target access type that is the same as the second access type in the first access type, sending a third registration indication to the UDM entity, where the third registration The indication is used to instruct the UDM entity to perform deregistration on a target AMF entity, where the target AMF entity is responsible for mobility management when the terminal device accesses a target PLMN in the first PLMN, where the target PLMN is The terminal device adopts a PLMN accessed by an access technology belonging to the target access type.
A network communication method, comprising:

The unified data management UDM entity receives a first registration indication from the terminal device, where the first registration indication is used to instruct the UDM entity to retain registration information of the first access and mobility management function AMF entity, the first AMF The entity is responsible for mobility management when the terminal device accesses the first public land mobile network PLMN, and the first PLMN is a PLMN that the terminal device has accessed;

And the UDM entity retains registration information of the first AMF entity according to the first registration indication.
The method according to claim 8, wherein before the UDM entity retains the registration information of the second AMF entity according to the first registration indication, the method further includes:

The UDM entity determines that the terminal device has a dual connectivity capability, wherein the dual connectivity capability is used to indicate that the terminal device supports accessing a PLMN by using an access technology of two access types simultaneously.
A network communication method, comprising:

The first access type to which the first access technology belongs when the terminal device accesses the first public land mobile network PLMN, and the second access technology to which the second PLMN is used when the terminal device accesses the second public network a second access type, wherein the first PLMN is a PLMN that the terminal device has accessed, the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a third generation. The partner plans a 3GPP access type and/or a non-3GPP access type, the second access type being a 3GPP access type or a non-3GPP access type;

When the UDM entity determines that the terminal device has a dual connectivity capability, and the second access type is different from the first access type, retaining registration information of the first access and mobility management function AMF entity, The first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN, and the dual connectivity capability is used to indicate that the terminal device supports access technologies that use two access types at the same time. Access to the PLMN.
The method of claim 10, wherein before the UDM entity retains registration information of the first AMF entity, the method further comprises:

The UDM entity determines that the identity of the second PLMN is different from the identity of the first PLMN.
The method of claim 10, wherein the method further comprises:

Deregistering the first AMF entity when the UDM entity determines at least one of the following:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type.
The method of claim 11 wherein the method further comprises:

Deregistering the first AMF entity when the UDM entity determines at least one of the following:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The identifier of the second PLMN is the same as the identifier of the first PLMN.
The method of claim 12 or 13, wherein the method further comprises:

The UDM entity notifies the first session management function SMF entity to release the session of the terminal device, wherein the first SMF is responsible for session management when the terminal device accesses the first PLMN.
The method of any of claims 10-14, wherein the method further comprises:

Deregistering the target AMF entity when the UDM entity determines that the same target access type as the second access type exists in the first access type;

The target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN in the first PLMN, and the target PLMN adopts an access technology belonging to the target access type for the terminal device. Access to the PLMN.
A terminal device, comprising:

An acquiring unit, configured to acquire a first access type to which the first access technology used when accessing the first public land mobile network PLMN, and a second access mode to which the second access technology used when accessing the second PLMN An incoming type, wherein the first PLMN is a PLMN that the terminal device has accessed, the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a third generation partner. Planning a 3GPP access type and/or a non-3GPP access type, the second access type being a 3GPP access type or a non-3GPP access type;

a processing unit, configured to send a first registration indication to the unified data management UDM entity when the second access type is different from the first access type, where the first registration indication is used to indicate the The UDM entity retains registration information of the first access and mobility management function AMF entity, and the first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN.
The terminal device according to claim 16, wherein the processing unit is further configured to:

Before transmitting the first registration indication to the UDM entity, determining that the identifier of the second PLMN is different from the identifier of the first PLMN.
The terminal device according to claim 16 or 17, wherein the processing unit is further configured to:

Determining that the terminal device has dual connectivity capability before sending the first registration indication to the UDM entity, where the dual connectivity capability is used to indicate that the terminal device supports access using two access types simultaneously Technology access to the PLMN.
The terminal device according to claim 16, wherein the processing unit is further configured to:

Sending a second registration indication to the UDM entity when at least one of the following is determined:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The second registration indication is used to indicate that the UDM entity performs deregistration on the first AMF entity, where the dual connectivity capability is used to indicate that the terminal device supports access technologies that use two access types at the same time. Access to the PLMN.
The terminal device according to claim 17, wherein the processing unit is further configured to:

Sending a second registration indication to the UDM entity when at least one of the following is determined:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The identifier of the second PLMN is the same as the identifier of the first PLMN;

The second registration indication is used to indicate that the UDM entity performs deregistration on the first AMF entity, where the dual connectivity capability is used to indicate that the terminal device supports access technologies that use two access types at the same time. Access to the PLMN.
The terminal device according to claim 19 or 20, wherein the second registration indication is further configured to trigger the UDM entity to notify the first session management function SMF entity to release the session of the terminal device, where The first SMF entity is responsible for session management when the terminal device accesses the first PLMN.
The terminal device according to any one of claims 16 to 21, wherein the processing unit is further configured to:

When it is determined that the same target access type as the second access type exists in the first access type, sending a third registration indication to the UDM entity, where the third registration indication is used to indicate Deleting, by the UDM entity, a target AMF entity, where the target AMF entity is responsible for mobility management when the terminal device accesses a target PLMN in the first PLMN, where the target PLMN is used by the terminal device The PLMN accessed by the access technology of the target access type.
A unified data management UDM entity, comprising:

a receiving unit, configured to receive, by the terminal device, a first registration indication, where the first registration indication is used to instruct the UDM entity to retain registration information of the first access and mobility management function AMF entity, the first AMF The entity is responsible for mobility management when the terminal device accesses the first public land mobile network PLMN, and the first PLMN is a PLMN that the terminal device has accessed;

And a processing unit, configured to reserve registration information of the first AMF entity according to the first registration indication.
The UDM entity of claim 23, wherein the processing unit is further configured to:

Before the registration information of the second AMF entity is retained according to the first registration indication, determining that the terminal device has dual connectivity capability, wherein the dual connectivity capability is used to indicate that the terminal device supports two types of simultaneous use. The access type access technology accesses the PLMN.
A unified data management UDM entity, comprising:

An acquiring unit, configured to acquire a first access type to which the first access technology used by the terminal device to access the first public land mobile network PLMN, and a second access technology to be used when accessing the second PLMN a second access type, wherein the first PLMN is a PLMN that the terminal device has accessed, the second PLMN is a PLMN to be accessed by the terminal device, and the first access type is a third generation. The partner plans a 3GPP access type and/or a non-3GPP access type, the second access type being a 3GPP access type or a non-3GPP access type;

a processing unit, configured to reserve registration information of the first access and mobility management function AMF entity when determining that the terminal device has dual connectivity capability, and the second access type is different from the first access type The first AMF entity is responsible for mobility management when the terminal device accesses the first PLMN, and the dual connectivity capability is used to indicate that the terminal device supports access by using two access types at the same time. Technology access to the PLMN.
The UDM entity of claim 25, wherein the processing unit is further configured to:

Before retaining the registration information of the first AMF entity, determining that the identifier of the second PLMN is different from the identifier of the first PLMN.
The UDM entity of claim 25, wherein the processing unit is further configured to:

Deregistering the first AMF entity when at least one of the following is determined:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type.
The UDM entity of claim 26, wherein the processing unit is further configured to:

Deregistering the first AMF entity when at least one of the following is determined:

The terminal device does not have dual connectivity capabilities;

The second access type is the same as the first access type;

The identifier of the second PLMN is the same as the identifier of the first PLMN.
The UDM entity according to claim 27 or 28, wherein the processing unit is further configured to:

Notifying the first session management function that the SMF entity releases the session of the terminal device, wherein the first SMF is responsible for session management when the terminal device accesses the first PLMN.
The UDM entity according to any one of claims 25 to 29, wherein the processing unit is further configured to:

Determining to de-register the target AMF entity when it is determined that the same target access type as the second access type exists in the first access type;

The target AMF entity is responsible for mobility management when the terminal device accesses the target PLMN in the first PLMN, and the target PLMN adopts an access technology belonging to the target access type for the terminal device. Access to the PLMN.