WO2018170697A1

WO2018170697A1 - Network access method and device

Info

Publication number: WO2018170697A1
Application number: PCT/CN2017/077372
Authority: WO
Inventors: 阮攀; 姜印清; 汤超
Original assignee: 华为技术有限公司
Priority date: 2017-03-20
Filing date: 2017-03-20
Publication date: 2018-09-27
Also published as: CN110476457A

Abstract

The present application relates to the technical field of communications, and in particular, relates to a network selection technology of a terminal. A network selection method of the terminal comprises: obtaining an equivalent public land mobile network (EPLMN) list; determining whether an EPLMN in the EPLMN list supports a first access technology or not; and if it is determined that the EPLMN does not support the first access technology, preventing using the first access technology to access the EPLMN.

Description

Network access method and device

Technical field

Embodiments of the present application relate to the field of communications technologies, and, more particularly, to network access technologies for communication devices.

Background technique

In current mobile communication networks (eg, GSM, WCDMA, and LTE networks), Public Land Mobile Network (PLMN) refers to the purpose of providing land mobile communication services to the public by the government or its approved operators. And establish and operate a network. The PLMN's unique identifier (PLMN ID) consists of MCC (Mobile Country Code) and MNC (Mobile Network Code).

When the user equipment (User Equipment, UE) is powered on, the UE selects a PLMN according to the priority order of the stored PLMN list and registers with the PLMN network. In most cases, the UE registers a Home PLMN (Home Public Land Mobile Network, HPLMN) and obtains network services under the HPLMN network. Since the coverage areas of different PLMN networks are different, the UE roams or switches to other networks during communication. With the continuous development of business cooperation between operators, the application of roaming networks has been well developed. In addition to obtaining services on the HPLMN, the UE can also obtain roaming services from networks of other operators that have signed a roaming agreement with the home network operator.

In a roaming scenario, an Equivalent Public Land Mobile Network (EPLMN) refers to a public land mobile network that is in the same position as the user terminal currently selected. Operators can configure EPLMN networks, which can share communication network resources. The EPLMN included in the list of equivalent PLMNs in the UE is considered to be PLMN for PLMN selection, cell selection, cell reselection, and handover equivalent to HPLMN.

After the UE registers with the Public Land Mobile Network (PLMN), the list of equivalent PLMNs is downloaded and saved from the currently registered PLMN. The UE updates the list of equivalent PLMNs during attach or track area update (TAU), specifically, if the UE receives a new equivalent in the Attach/TAU accept message For the list of PLMNs, the UE updates the list of locally saved equivalent PLMNs.

Currently, the EPLMN does not distinguish the access technology. For example, only a part of the EPLMN in the EPLMN list supports the LTE service, and the remaining part of the EPLMN supports the UMTS (3G) or GSM (2G) network service, and the LTE network service is not required by the operator due to the service requirement. Open roaming, UMTS and GSM network services open roaming. When the mobile phone attempts to register on the EPLMN by using the LTE technology, since the LTE network service does not have a roaming agreement, each registration request is rejected by the network, and the mobile phone is dropped, which affects the user experience.

Summary of the invention

This document describes a network access method and device to enhance the endurance of an electronic device.

In a first aspect, an embodiment of the present application provides a network access method. The method includes: obtaining an Equivalent Public Land Mobile Network (EPLMN) list; determining whether the EPLMN in the EPLMN list supports the first access technology; and when determining that the EPLMN does not support the first access technology, blocking the adoption The first access technology accesses the EPLMN.

In some roaming scenarios, the operator limits the roaming of specific communication technologies for the EPLMN. In order to avoid situations where the registration of the EPLMN network with the radio access technology that does not have roaming is denied, it is necessary to consider what might be an appropriate radio access technology. When it is determined that the EPLMN does not support an access technology, the access technology is prevented or prevented from accessing the EPLMN network, and the access technology can be avoided to initiate an ATTACH registration request to the network device, thereby avoiding the registration request being rejected. network.

In a possible design, the EPLMN is accessed by using a second access technology supported by the EPLMN, and the second access technology is different from the first access technology. For example, the first access technology is an LTE access technology, and the second access technology is a GSM or UMTS access technology. When the EPLMN does not support the LTE access technology, the other access technologies supported by the EPLMN can still be used to access the EPLMN, so that the user can register to the roaming network and obtain the network service.

In one possible design, preventing access to the EPLMN by using the first access technology may be implemented by blocking delivery of the EPLMN to an access stratum (AS) supporting the first access technology. The PLMN selection, cell selection, cell reselection or handover operation of the terminal is mainly performed in cooperation with a non-access stratum (NAS, Non-Access Stratum) and (AS, Access Stratum). The NAS does not deliver the EPLMN to the AS that supports the first access technology, so that the terminal attempts to register with the EPLMN network by using the first access technology, thereby avoiding the dropped network caused by the registration request being rejected.

In one possible design, the first access technology is a Long Term Evolution (LTE) access technology.

In one possible design, the terminal stores an extended EPLMN list for each EPLMN including information indicating whether the first access technology is supported by the EPLMN. The stored extended EPLMN list is queried according to the identifier of the EPLMN in the EPLMN list, and it is determined according to the query result whether the EPLMN supports the first access technology.

On the other hand, the embodiment of the present application provides a terminal, which has the function of implementing the terminal in the design of the foregoing method. The functions may be implemented by hardware or by corresponding software implemented by hardware. The hardware or software includes one or more modules corresponding to the functions described above. The modules can be software and/or hardware.

In one possible design, the structure of the terminal includes a memory and a processor. The memory is configured to store program code and data that the processor performs operations. The processor is configured to obtain an Equivalent Public Land Mobile Network (EPLMN) list; determine whether an EPLMN in the EPLMN list supports a first access technology; and when the EPLMN does not support the first access technology, Blocking access to the EPLMN using the first access technology.

In a further aspect, the embodiment of the present application provides a computer storage medium for storing computer software instructions used by the terminal, which includes a program designed to execute the above aspects.

Compared with the prior art, the solution provided by the present application can improve the roaming experience of the end user.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings to be used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description are only some of the present application. For the embodiments, those skilled in the art can obtain other drawings according to the drawings without any creative work.

1 is a schematic diagram of a terminal roaming scenario according to an embodiment of the present application;

2 is a schematic diagram of a wireless network protocol stack model according to an embodiment of the present application;

3 is a schematic diagram of a NAS providing an EPLMN to an AS;

4 is a schematic diagram of a NAS providing an EPLMN to an AS according to an embodiment of the present application;

5 is a flowchart of a terminal performing PLMN selection, cell selection/reselection, or handover according to an embodiment of the present application;

6 is a block diagram showing the composition of a terminal in accordance with one embodiment of the present application.

detailed description

The technical solutions in the embodiments of the present application are described in conjunction with the accompanying drawings in the embodiments of the present application. It is obvious that the described embodiments are a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application without departing from the inventive scope are the scope of the present application.

In the description of the present application, it is to be understood that the terms "first", "second", "third" and the like are used for descriptive purposes only and are not to be construed as indicating a primary or secondary relationship, and therefore cannot be understood as a Application restrictions.

In addition, various aspects are described in connection with a terminal in this application, and the terminal may be a wireless terminal. A terminal may also be called a device, a subscriber unit, a subscriber station, a mobile station, a mobile station, a mobile device, a remote station, a remote terminal, an access terminal, a user terminal, a communication device, a user agent, a user equipment, or a user equipment (UE). The wireless terminal can be a cellular telephone, a satellite telephone, a cordless telephone, a Session Initiation Protocol (SIP) telephone, a personal digital assistant (PDA), a wirelessly connected handheld device, a computing device, or other processing device connected to a wireless modem. Moreover, various aspects are described in connection with a base station in this application. A base station can be utilized for communicating with wireless terminals and can also be referred to as an access point, a Node B, or some other terminology. The base station can be implemented as a radio base station of any suitable radio technology, for example, GSM (Global System for Mobile Communications) BTS (Base Transceiver Station), HSPA (High Speed Packet Access) / WCDMA (Wireless Code Division Multiple Access) network NodeB, or an eNodeB of an LTE (Long Term Evolution) communication network.

The techniques described herein may be used in various wireless communication networks, such as LTE, LTE Advanced, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile Communications GSM, and only a few possible techniques for radio communication are mentioned herein. . UTRA (Universal Terrestrial Radio Access), E-UTRA (Evolved UTRA), GSM, UMTS (Universal Mobile Telecommunications System), are described in documents from an organization named "3rd Generation Partnership Project" (3GPP) LTE and 5G (fifth generation communication system) not yet commercially available. These wireless technologies and standards are well known in the art and will not be described here. For clarity, certain aspects of the present techniques are described below for LTE, which is used in many of the following descriptions. It should be noted that LTE terminology is used by way of illustration, but the scope of the invention is not limited to LTE.

1 depicts a scenario in which a terminal 104 moves from PLMN-1 to an area that is simultaneously covered by PLMN-2 and PLMN-3. In Fig. 1, the coverage areas of PLMN-1, PLMN-2, and PLMN-3 are 101, 102, and 103, respectively.

With the development of communication technologies, communication networks can generally support different communication technologies or protocols, and a new generation of technologies can be compatible with the old generation technology. In Figure 1, the communication system PLMN-1 only supports fourth generation (LTE) wireless communication technologies or protocols. PLMN-2 and PLMN-3 can support both second generation (GSM/2G), third generation (UMTS/3G) and fourth generation (LTE/4G) wireless communication technologies or protocols.

In some applications, it is desirable to be able to limit roaming protocols for a particular communication technology or to a particular communication technology. For example, a network operator without a 2G license must rely on a roaming agreement with a 2G network operator to provide continuous service to its users. Taking FIG. 1 as an example, PLMN-1 is the network of the operator A, PLMN-2 is the network of the operator B, and the PLMN-3 is the network of the operator C. Carrier A has only 4G networks, while Carrier B and Carrier C both have 2G/3G/4G networks. Carrier A needs to sign a roaming agreement with Carrier B to use Carrier 2's 2G/3G network. However, Carrier B prohibits 4G users of Carrier A from accessing Carrier B's 4G network. Carrier C allows the 4G users of Carrier A to access the 4G network of Carrier C.

The terminal 104 moves from the coverage area 101 to the overlapping area of the coverage area 102 and the coverage area 103, and the equivalent PLMN list created by the mobility management entity (MME) may include PLMN-2 and PLMN-3. In this case, since the terminal 104 can randomly select the PLMN from the equivalent PLMN list for PLMN selection, cell selection, cell reselection, or handover, the PLMN-2 can be selected, but the PLMN-2 prohibits the operator A. The user (ie, terminal 104) accesses its 4G network. Therefore, when the terminal 104 attempts to register to the PLMN-2 by using the LTE technology, since the operator A and the operator B do not sign the 4G network roaming agreement, each time the LTE network registration request is rejected by the network, the terminal 104 will drop the network.

In general, the criteria used by terminal 104 to determine the appropriate cell to camp on is typically the radio condition between terminal 104 and the base station providing the cell. For example, if the terminal 104 finds itself in the coverage area of the first cell and the second cell and the radio link shared with the first cell is deteriorating, the mobile device will seek to reselect to the second cell. During the cell selection/reselection process, various messages will be exchanged between the terminal 104 and the core network. These messages include authentication, registration, and configuration messages. In Figure 1, terminal 104 moves into an area that is covered by a cell from a third network (PLMN-3). under these circumstances, If there is a suitable roaming agreement between the first network (PLMN-1) and the third network (PLMN-3), the terminal 104 will be able to camp on the cell of the third network. Various processes involved in cell selection and cell reselection for a general 3GPP compatible network are explained in further detail in 3GPP TS 25.304, and are not described herein again.

In order to avoid the occurrence of the above mentioned radio access technology (e.g., LTE) registration network with unopened roaming being rejected. In a roaming scenario, the PLMN selection, cell selection, cell reselection or handover procedure needs to consider what might be an appropriate Radio Access Technology (RAT). In some embodiments of the present application, PLMN selection, cell selection, cell reselection, or handover includes a radio access technology selection procedure.

In order to be able to select the radio access technology, the various parts of the EPLMN list need to become "radio access technology aware". The EPLMN list of "Radio Access Technology Awareness" is referred to herein as an extended EPLMN list. To facilitate differentiation between different radio access technologies, in some embodiments of the application, an indicator or field may be used to indicate the radio access technology available in the EPLMN. For example, one bit can be used as a flag indicating whether the RAT is available, the indicator is set to 1 when the EPLMN supports a certain RAT, and is set to 0 when the EPLMN does not support the RAT. Of course, the indicator can consist of two or more bits. Table 1 shows an extended EPLMN list that is assigned a RAT-Supported indicator according to the operator's service provisioning policy.

Table 1 First example of extending the EPLMN list

The EPLMN and its supported RATs are listed in the extended EPLMN list in Table 1. The EPLMN-1 supports three RATs, GSM, UMTS, and LTE. The EPLMN-2 supports GSM and UMTS, in combination with the above description. The operator of the user storing the terminal of the extended EPLMN list shown in Table 1 and the operator providing the EPLMN-2 network do not sign the 4G network roaming agreement, so the EPLMN-2 does not support the LTE RAT. Still taking FIG. 1 as an example, EPLMN-1 may be the network of the operator C, and the EPLMN-2 may be the network of the operator B.

In some embodiments, only one RAT is required to be supported in the extended EPLMN list, for example, only indicating whether the LTE RAT is supported. Table 2 shows an extended EPLMN list showing that the LTE-Supported indicator is assigned according to the operator's service provisioning policy.

Table 2 Example of extending the EPLMN list

EPLMN IDEPLMN ID	RATRAT	LTE-SupportedLTE-Supported
EPLMN-1EPLMN-1	LTE LTE	11
EPLMN-2EPLMN-2	LTELTE	00

The EPLMN and its support for the LTE RAT are listed in the extended EPLMN list in Table 2. The EPLMN-1 LTE RAT and the EPLMN-2 do not support the LTE RAT. The expansion shown in Table 2 is stored in combination with the above description. The operator of the user of the terminal of the EPLMN list and the operator providing the EPLMN-2 do not sign the 4G network roaming agreement, so the EPLMN-2 cannot provide the LTE roaming service to the end user, that is, the EPLMN-2 does not support the LTE RAT.

Tables 1 and 2 primarily include 3GPP compatible radio access technologies, however, it should be understood that additional radio access technologies such as WLAN (e.g., WiFi), Bluetooth, WiMax, etc., may also be included. In one embodiment of the present application, the network provides the terminal with an extended EPLMN list as shown in Tables 1 and 2. The network may send an extended EPLMN list to the terminal during location update, attach, routing area update, or Tracking area update (TAU). In order to transmit the extended EPLMN list, the network may provide an Information Element (IE) with a list of PLMN identities of equivalent PLMNs in the Location Update Accept, Attach Accept, Routing Area Update Accept, or Tracking Area Update Accept message.

In another embodiment of the present application, the network only provides the terminal with a regular EPLMN list, and the terminal may store the following in Table 1 or in a Subscriber Identity Module (SIM), a Universal SIM (USIM), or some other non-volatile storage module. The extended EPLMN list shown in Table 2. A conventional EPLMN list may only contain a PLMN ID, which may include a Mobile Country Code (MCC) and a Mobile Network Code (MNC). Referring to the implementation above, the network may provide an Information Element (IE) containing a regular EPLMN list in a Location Update Accept, Attach Accept, Routing Area Update Accept, or Tracking Area Update Accept message. After receiving the regular EPLMN list sent by the network, the terminal searches for the locally stored extended EPLMN list, and accordingly determines the RAT supported by the PLMN in the regular EPLMN list. Compared with the extension of the EPLMN list on the network side, the terminal can save the extended EPLMN list by using the current network to deliver the EPLMN process without any modification on the network side, which enhances the convenience of the implementation. Moreover, the number of operators in the world is limited (several hundred), and the extended EPLMN list created according to the roaming agreement between these operators does not occupy a large storage space in the terminal, which is convenient for the terminal to manage.

Table 3 Regular EPLMN List

EPLMN IDEPLMN ID
EPLMN-1(MCC-1,MNC-1)EPLMN-1 (MCC-1, MNC-1)
EPLMN-2(MCC-2,MNC-2)EPLMN-2 (MCC-2, MNC-2)

The following describes how the terminal performs PLMN selection, cell selection, cell reselection or handover operation using the extended EPLMN list of "radio access technology sensing".

Taking PLMN selection as an example, PLMN selection can be divided into manual PLMN selection and automatic PLMN selection. Select (see the 3GPP TS 23.122 protocol for details). The so-called manual PLMN selection means that the user selects the PLMN to be accessed according to the list of PLMNs displayed on the terminal, and can display according to the priority of each PLMN; the so-called automatic PLMN selection means that the terminal automatically selects the PLMN to be accessed according to the priority order of the PLMN. And initiate registration. The cell selection, the cell reselection, or the handover operation are described in detail in the 3GPP protocol specification, and are not described herein again.

In order to introduce how the terminal performs PLMN selection, cell selection, cell reselection or handover operation using the extended EPLMN list, the following describes the terminal wireless protocol stack model. 2 illustrates an exemplary wireless network protocol stack model of a network service over a connection-oriented transport session that includes a non-access stratum (NAS, Non-Access Stratum) over an Access Stratum (AS). The wireless network protocol stack includes seven layers: an application layer, a transport layer, an Internet layer, a network layer, a link layer, and a physical layer. In one example, the access layer (AS, Access Stratum) of the terminal receives the PLMN list provided by the non-access stratum (NAS, Non-Access Stratum), and starts the PLMN search process.

A NAS is a network layer that provides network services such as mobility management, connection management, and session management between a core network (CN) and a user equipment (UE). The AS is a link layer that provides NAS with lower level services such as radio resource control, radio link control, media access control, and physical layer services.

As shown in FIG. 3, the NAS layer of the GSM/UMTS/LTE-enabled multimode terminal 300 has a mobility management module 301 and an EMM (Enhanced Evolved Packet System (EPS) mobility management) module 302, and the access layer according to its support The incoming technology can also be divided into a GSM access layer 303, a UMTS access layer 304, and an LTE access layer 305. Many NAS functions in the UMTS system are inherited from GSM, so the mobility management module 301 can be responsible for both GSM and UMTS mobility management. In addition, not shown, the NAS layer of the terminal 300 also supports functions such as ESM (Enhanced Session Management) and SM (Session Management).

The PLMN selection, cell selection, cell reselection or handover operation of the terminal is mainly completed by the cooperation of the NAS and the AS. Taking the PLMN selection as an example, after the NAS layer of the terminal selects a PLMN network with the highest priority, the selected PLMN network is notified to the radio resource control module (RRC) of the access layer, and the cell camping condition is controlled by the RRC. It is determined that if the terminal can normally camp, the terminal completes the selection process of the entire PLMN, enters the normal resident state, and exits the PLMN selection process.

Referring to Figure 3, the mobility management module 301 provides the GSM access layer 303 with an EPLMN (the path indicated by arrow 306 in the figure) requesting the GSM access layer 303 to camp on the active cell. At the same time, the mobility management module 301 provides the EPLMN (the path indicated by arrow 307 in the figure) to the UMTS access layer 304, requesting the UMTS access layer 304 to camp on the active cell. The enhanced mobility management module 302 provides the EPLMN (the path indicated by arrow 308 in the figure) to the LTE access layer 305, requesting the LTE access layer 305 to camp on the active cell. If the EPLMN does not support the LTE RAT, the registration request initiated to the LTE network is rejected by the network, and the terminal will drop the network.

In order to avoid the occurrence of the aforementioned mentioned radio access technology (e.g., LTE) registration network with unopened roaming being rejected. When the NAS provides the EPLMN to the AS, the NAS can determine whether the EPLMN supports the first access technology (RAT). If it is determined that the EPLMN does not support the first RAT, the NAS can block The first RAT is prevented from accessing the EPLMN, so that the situation in which the first RAT registration network is rejected may be avoided.

Taking the first RAT as the LTE access technology as an example. Referring to FIG. 4, it is assumed that the ATM layer determines that the EPLMN does not enable the roaming service of the LTE access technology, that is, determines that the EPLMN does not support the LTE RAT, then the enhanced mobility management module 302 does not go to the LTE. The access layer 305 provides the EPLMN (the path indicated by arrow 308 in the figure is broken), thereby preventing or avoiding access to the EPLMN using the LTE RAT. Optionally, the terminal may still access the EPLMN by using the second access technology supported by the EPLMN, and the second access technology may be a UMTS access technology or a GSM access technology, where the paths indicated by

arrows

306 and 307 are still Unblocked. That is, the mobility management module 301 still provides the EPLMN (arrow 306 in the figure) to the GSM access layer 303 requesting the GSM access layer 303 to camp on the active cell. At the same time, the mobility management module 301 provides the EPLMN (arrow 307 in the figure) to the UMTS access layer 304 requesting the UMTS access layer 304 to camp on the active cell.

5 is a flow diagram of a process performed by a terminal for PLMN selection, cell selection, cell reselection, or handover, in accordance with an embodiment of the present application.

Referring to FIG. 5, in step 510, the terminal acquires an EPLMN list. In one example, a non-access stratum (NAS) acquires the EPLMN list, and the EPLMN list includes at least one piece of EPLMN information. Optionally, before step 510, the terminal further determines that the PLMN selection, the cell selection, the cell reselection, or the handover is necessary. In an embodiment of the present application, the EPLMN list is an extended EPLMN list, and the extended EPLMN list as shown in Table 1 and Table 2 is provided by the network to the terminal. In another embodiment of the present application, the EPLMN list is a regular EPLMN list, the regular EPLMN list may only include a PLMN ID, and the PLMN ID may include a Mobile Country Code (MCC) and a Mobile Network Code (MNC).

At step 520, the terminal determines whether the EPLMN in the EPLMN list supports the first access technology (RAT).

As described above, if the EPLMN list is an extended EPLMN list, the terminal can directly know whether the EPLMN supports the first RAT, for example, according to the RAT-Supported indicator of the extended EPLMN list shown in Table 1, whether the EPLMN supports the first RAT.

If the EPLMN list is a regular EPLMN list, the terminal may store an extended EPLMN list as shown in Table 1 or Table 2 in a Subscriber Identity Module (SIM), a Universal SIM (USIM), or some other non-volatile storage module. The terminal queries the stored extended EPLMN list according to the identifier of the EPLMN in the EPLMN list. The example of the extended EPLMN list is shown in Table 1 or Table 2. The extended EPLMN list includes, for each EPLMN, information indicating whether the first access technology is supported by the EPLMN. The terminal determines, according to the query result, whether the EPLMN supports the first access technology. For example, the conventional EPLMN list obtained by the terminal is shown in Table 3. The extended EPLMN list stored by the terminal is as shown in Table 2. The terminal matches the EPLMN-2 in the regular EPLMN list with the EPLMN-2 in the extended EPLMN list. If successful, it can be known that EPLMN-2 does not support LTE RAT.

In one example, the first RAT is LTE, and the non-access stratum (NAS) determines whether the EPLMN is supported. Hold the first RAT. If it is determined that the EPLMN does not support the first RAT, the process proceeds to step 530, where access to the EPLMN with the first RAT is blocked. That is, the first RAT is temporarily disabled, and the access technology is prevented from accessing the EPLMN network, and the access technology can be avoided to initiate an ATTACH registration request to the network device, thereby avoiding the dropped network caused by the registration request being rejected. In one example, the EPLMN may be blocked/not passed to an access layer (AS) supporting the first access technology to disable the first RAT. In an embodiment, when the first RAT is an LTE RAT, the non-access stratum (NAS) may not transmit the EPLMN to the LTE access stratum (AS). Specifically, the enhanced mobility management module 302 does not The LTE access layer 305 passes the EPLMN.

Optionally, in step 540, the terminal accesses the EPLMN by using a second access technology supported by the EPLMN, where the second access technology is different from the first access technology, for example, when the first access technology is LTE. The second access technology may be an access technology of UMTS (such as WCDMA). Continue to allow access to the same EPLMN with other RATs supported by the EPLMN. Specifically, the mobility management module 301 can deliver the EPLMN to the GSM access layer 303 and the UMTS access layer 304 as shown in FIG.

If it is determined in step 520 that the EPLMN supports the first RAT, the process proceeds to step 550 where the first access technology is used to access the EPLMN. In an example, the non-access stratum (NAS) delivers the EPLMN to an access stratum (AS) supporting the first access technology. For example, if the first access technology is LTE, then the NAS layer delivers the EPLMN to LTE Access Layer (AS). Specifically, as shown in FIG. 3, the enhanced mobility management module 302 delivers the EPLMN to the LTE access layer 305. At the same time, the mobility management module 301 can deliver the EPLMN to the GSM access layer 303 and the UMTS access layer 304.

FIG. 6 is a block diagram showing the composition of a terminal 104 in accordance with one embodiment of the present application. Referring to FIG. 6, the terminal 104 includes a radio communication unit 610, a memory 620, and a processor 630. The terminal 104 may further include a display unit, an input unit, a global positioning system (GPS) unit, and the like, not shown. Processor 630 can be responsible for executing various software programs (e.g., applications and operating systems) to provide computing and processing operations for terminal 104. The radio communication unit 610 is responsible for the communication function of the electronic device. The radio communication unit 610 establishes a communication channel with a supportable mobile communication network to implement voice telephony, video conferencing, and data communication. The radio communication unit 610 includes a radio frequency (RF) transmitter and an RF receiver, wherein the RF transmitter is for upconverting and amplifying the transmission signal, and the RF receiver is for low noise amplification and down conversion of the received signal. The radio communication unit 610 includes a cellular communication module (eg, a third generation (3G) cellular communication module and/or a 4G cellular communication module) and a digital broadcast module.

The memory 620 is configured to store various data executed and processed in the terminal 104, as well as an operating system (OS) and various applications of the electronic device. The memory 620 is implemented using at least one of the following items, but is not limited thereto: RAM, ROM, flash memory, EPROM, and EEPROM. The memory 620 includes a data area and a program area. The data area of the memory 620 stores data generated by the terminal 104 and downloaded from the outside.

The processor 630 controls the terminal 104 to perform processes such as PLMN selection, cell selection, cell reselection, or handover according to one of the above embodiments. For example, the processor 630 can execute the method flow as shown in FIG. 5 to perform The process of PLMN selection, cell selection, cell reselection or handover. The radio communication unit 610 transmits and receives signals required to perform one of the above embodiments.

The above processor for performing the embodiments of the present application may be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a transistor logic device. , hardware components or any combination thereof. It is possible to implement or carry out the various illustrative logical blocks, modules and circuits described in connection with the present disclosure. The processor may also be a combination of computing functions, for example, including one or more microprocessor combinations, a combination of a DSP and a microprocessor, and the like.

The steps of a method or algorithm described in connection with the present disclosure may be implemented in a hardware or may be implemented by a processor executing software instructions. The software instructions may be comprised of corresponding software modules that may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable hard disk, CD-ROM, or any other form of storage well known in the art. In the medium. An exemplary storage medium is coupled to the processor to enable the processor to read information from, and write information to, the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. Additionally, the ASIC can be located in the user equipment. Of course, the processor and the storage medium may also reside as discrete components in the user equipment.

Those skilled in the art will appreciate that in one or more examples described above, the functions described herein can be implemented in hardware, software, firmware, or any combination thereof. Those skilled in the art will readily appreciate that the present application can be implemented in a combination of hardware or hardware and computer software in combination with the elements and algorithm steps of the various examples described in the embodiments disclosed herein. Whether a function is implemented in hardware or computer software to drive hardware depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods to implement the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present application. When implemented in software, the functions may be stored in a computer readable medium or transmitted as one or more instructions or code on a computer readable medium. Computer readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one location to another. A storage medium may be any available media that can be accessed by a general purpose or special purpose computer.

The specific embodiments of the present invention have been described in detail with reference to the specific embodiments of the present application. It is to be understood that the foregoing description is only The scope of protection, any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the present application are included in the scope of protection of the present application.

Claims

A network access method, the method comprising:

Obtain a list of equivalent Public Land Mobile Networks (EPLMN);

Determining whether the EPLMN in the EPLMN list supports the first access technology;

When it is determined that the EPLMN does not support the first access technology, accessing the EPLMN by using the first access technology is prevented.
The method of claim 1 wherein the method further comprises:

Accessing the EPLMN by using a second access technology supported by the EPLMN, where the second access technology is different from the first access technology.
The method according to claim 1 or 2, wherein the preventing access to the EPLMN by using the first access technology comprises:

Blocking the transfer of the EPLMN to an access stratum (AS) supporting the first access technology.
The method according to any one of claims 1 to 3, wherein the first access technology is a Long Term Evolution (LTE) access technology.
The method according to any one of claims 1 to 4, wherein the determining whether the EPLMN in the EPLMN list supports the first access technology comprises:

Querying the stored extended EPLMN list according to the identifier of the EPLMN in the EPLMN list, wherein the extended EPLMN list includes, for each EPLMN, information indicating whether the first access technology is supported by the EPLMN;

Whether the EPLMN supports the first access technology is determined according to the query result.
A terminal, wherein the terminal comprises:

a memory configured to store program code and data for the processor to perform operations;

a processor configured to: obtain an Equivalent Public Land Mobile Network (EPLMN) list; determine whether an EPLMN in the EPLMN list supports a first access technology; and when determining that the EPLMN does not support the first access technology Blocking access to the EPLMN by using the first access technology.
The terminal according to claim 6, wherein the processor is further configured to access the EPLMN by using a second access technology supported by the EPLMN, the second access technology being different from the An access technology.
The terminal of claim 6 or 7, wherein the processor is configured to block delivery of the EPLMN to an access layer (AS) supporting the first access technology.
The terminal according to any one of claims 6 to 8, wherein the first access technology is a Long Term Evolution (LTE) access technology.
The terminal according to any one of claims 6 to 9, wherein the processor is configured to query a stored extended EPLMN list according to an identifier of an EPLMN in the EPLMN list, wherein the extended EPLMN list is for each The EPLMN includes information indicating whether the first access technology is supported by the EPLMN, and determines whether the EPLMN supports the first access technology according to the query result.