Network switching method in communication terminal

Abstract

[Problem] To provide a network switching method in a communication terminal that enables quick network switching by performing a registration process of terminal information to a network without rejection by the network. [Solution] A network switching method in a communication terminal that comprises an embedded SIM (eSIM) which stores a plurality of pieces of profile information for use in communication, a local profile assistant (LPA) application and a modem control unit that receives a profile switching request from the LPA application, that performs switching of the plurality of pieces of profile information stored in the eSIM, that notifies the LPA application of the completion of the profile switching, and that performs a terminal information registration process with respect to an external network, said network switching method being characterized in that: prior to or simultaneously with output of the profile switching request, the LPA application notifies the modem control unit of access point name (APN) information corresponding to the profile information after the switching; and the modem control unit performs the terminal information registration process with respect to the external network using the received APN information after the profile switching.

Description

Network switching method in communication terminal

[0001] The present invention relates to a network switching method in a communication terminal, and particularly to a network switching method suitable for speeding up profile switching in a communication terminal equipped with an eSIM.

[0002] SIM (Subscriber Identity Module) cards that enable communication services on 4G / 5G-compatible communication terminals include physical SIMs and eSIMs, as shown in Figures 7(a) and 7(b). eSIM, short for Embedded SIM, is a SIM card built into the device. Because it does not require a physical SIM card like the one shown in Figure 7(a), it offers advantages such as thinner and lighter devices and reduced risk of SIM card loss or damage. As shown in Figure 7(b), in communication terminals equipped with eSIMs, the contents of the eSIM card can be rewritten online and multiple subscriber information (profiles) can be stored, allowing users to switch profiles depending on their needs. Profile switching is typically performed manually by the user, and can be performed at the user's request. However, automatic profile switching may occur during communication, and if the profile switching time is long, communication will be unavailable for a longer period, causing inconvenience to the user.

[0003] The eSIM standard is defined by GSMA (Global System for Mobile Communications Association), a mobile communications industry organization, and eSIM profile management is explained in SGP.22 as follows: Figure 8 shows a configuration diagram of an eSIM operation system 81. Figure 8 is quoted from SGP.22 Figure 1: Remote SIM Provisioning System, LPA in the Device.

[0004] As shown in FIG. 8 , a communication terminal 82 writes a profile to an eSIM (eUICC) 84 via an LPA (Local Profile Assistant) application 83. When a profile is downloaded and written from the network via OTA (Over The Air), it is written from an SM-DP+ (Subscription Manager Data Preparation) server 87, which manages the profile, via the LPA application 83. Multiple profiles can be stored in the eSIM 84, and a user 86 can select a profile via a terminal app 85 and the LPA application 83. When a profile is selected, that information is used to register terminal information to the network. This registration of terminal information is performed according to the 3GPP TS24.301 5.5.1 Attach Procedure (hereinafter referred to as the attach process) in FIG. 9 . The attach process sequence (quoted from the 3GPP (registered trademark) standard) is shown in FIG. 9 . FIG. 9 specifies an attach process sequence between a UE (user equipment) and an MME (Mobility Management Entity) of a network, and includes a sequence for permitting the attach process by issuing an attach request, an attach permission, and an attach completion, and a sequence for rejecting the attach process by issuing an attach request and an attach reject.

[0005] GSMA: https: / / www. gsma. com / esim / resources / sgp-22-v3-1 / 3GPP (registered trademark): http: / / www. 3GPP. org /

[0006] When an eSIM holds multiple profiles, during the process of switching eSIM profiles, the modem control unit that performs network registration starts the attach process when the profile switch is complete. However, at this time, the modem control unit is not notified of the change in APN (Access Point Name) information required for data communication, and the change is rejected by the network, resulting in the issue of it taking a long time before communication becomes possible.

[0007] The present invention has been devised in light of the above background, and its purpose is to provide a network switching method for a communication terminal that can quickly switch networks by notifying the modem control unit of pre-stored APN information at the time a profile switch occurs, thereby registering the terminal information to the network without being rejected by the network.

[0008] A first aspect of the present invention provides a network switching method for a communication terminal including an eSIM (embedded SIM) that stores multiple pieces of profile information used for communication; an LPA (Local Profile Assistant) application that outputs a profile switching request in response to a user's profile switching operation; and a modem control unit that receives the profile switching request from the LPA application, switches the multiple pieces of profile information of the eSIM, notifies the LPA application of completion of the profile switching, and performs a process of registering terminal information to an external network, wherein the LPA application notifies the modem control unit of APN (Access Point Name) information corresponding to the profile information after switching before or simultaneously with outputting the profile switching request, and the modem control unit performs a process of registering terminal information to the external network using the received APN information after the profile switching.

[0009] The network switching method in a communication terminal according to the second invention is characterized in that, in the first invention, the modem control unit sends a registration request to the external network using the APN information received after the profile switching, and upon receiving registration permission from the external network, performs registration processing of the terminal information by sending a registration completion to the external network.

[0010] A network switching method in a communication terminal according to a third aspect of the present invention is the method of the first or second aspect of the present invention, characterized in that the profile switching operation is automatically performed by a robot or a cybernetic avatar.

[0011] A fourth aspect of the present invention is a network switching method in a communication terminal according to the first or second aspect of the present invention, characterized in that the APN information includes an access point name, an APN name, a user name, a password, and an authentication type.

[0012] According to the first to fourth inventions having the above-described configuration, a network switching method can be realized in a communication terminal that can quickly switch networks by notifying the modem control unit of APN information that has been stored in advance at the time a profile switch occurs, and by performing a process of registering the terminal information to the network without being rejected by the network.

[0013] According to the first to fourth inventions, when a communication terminal using an eSIM uses multiple profiles and the profile is switched by user operation or automatically, the APN information after the profile switch is notified to the modem control unit in advance, thereby enabling the network to be used quickly after the profile switch.

[0014] FIG. 1 is a configuration diagram of a communication terminal system to which the present invention is applied. FIG. 2 is a flowchart showing the procedure for switching eSIM profiles in an embodiment of the present invention. FIG. 3 is a processing sequence diagram of a network switching method in a communication terminal according to an embodiment of the present invention. FIG. 4 is a processing sequence diagram of a network switching method in a general communication terminal. FIG. 5 is a processing sequence diagram of a high-speed network switching method in a communication terminal according to an embodiment of the present invention. FIG. 6 is an explanatory diagram of automatic profile switching when moving from public 5G to local 5G according to an embodiment of the present invention. FIG. 7 is an explanatory diagram of a known physical SIM and eSIM, where FIG. 7(a) shows a physical SIM and FIG. 7(b) shows an eSIM configuration. FIG. 8 is a configuration diagram of an eSIM operation system. FIG. 9 is an attachment processing sequence diagram.

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

[0016] First, a network switching method in a communication terminal according to an embodiment of the present invention will be described with reference to FIGS.

[0017] Fig. 1 is a configuration diagram of a communication terminal system to which the present invention is applied. Fig. 2 is a flowchart showing an eSIM profile switching procedure in an embodiment of the present invention. Fig. 3 is a processing sequence diagram of a network switching method in a communication terminal according to an embodiment of the present invention.

[0018] The communication terminal 2 applied to this embodiment includes an LPA application 21 , a modem control unit 22 , and an eSIM 23 .

[0019] By using a communication terminal 2 with a built-in eSIM, a user 1 can switch profiles by performing a profile switching operation in the eSIM 23. Because the user 1 can perform the process of registering terminal information to the network 3 (attachment process) by operating the communication terminal 2, there is no need for a SIM card provided by a communication carrier as in the case of conventional physical SIM cards.

[0020] The communication terminal 2 is an eSIM-compatible communication mobile terminal (e.g., a smartphone, etc.), and also includes a portable PC with an eSIM built in, a tablet PC with an eSIM built in, a mobile robot equipped with the communication terminal 2, etc. The profile in the eSIM 23 can be switched in response to a profile switching operation by the user 1. Here, the communication terminal 2 is described with only the main configuration of the present invention, and although it has the configuration necessary for wireless communication, it is similar to a known configuration and is therefore not shown in the figure.

[0021] The LPA application 21 works in conjunction with a Subscription Manager (SM) server to provide management functions such as downloading profiles to the eSIM 23 and switching and deleting profiles. The LPA application 21 has at least a Local Profile Download (LPD) function and a Local User Interface (LUI) function. The LPD function is a function that downloads profiles from the SM server and stores and installs them in the eSIM 23 in the communication terminal 2. The LUI function is a function that provides a UI for operating profiles on the eSIM 23 (such as displaying a list, switching, and deleting).

[0022] The modem control unit 22 performs network registration processing (attach processing) of the terminal information using the new profile information.

[0023] eSIM 23 is an abbreviation for embedded Subscriber Identity Module, and refers to an embedded SIM. Multiple profiles can be written into the eSIM 23 via a network.

[0024] The network 3 is a wireless communication network through which the communication terminal 2 performs wireless communication, such as a local 5G network, a public 5G network, a private 5G network, a public 3G network, a public 4G network, a private LTE network, or a Wi-Fi (registered trademark) network. A private 5G network is a dedicated network that is not self-operated but is constructed using a network of a telecommunications carrier (carrier). A private LTE network is a self-operated dedicated network that is constructed using a mobile communication method generally called 4G.

[0025] Communication becomes possible by installing profile information for accessing these networks 3 in the eSIM 23 in advance. Alternatively, if multiple profiles are stored in the eSIM 23 in advance, the modem control unit 22 can start communication by performing a process of registering terminal information to the network 3 (attachment process). In the case of public 3G, 4G, and 5G networks, subscriber registration with a telecommunications carrier is performed in advance, multiple profiles are installed in the eSIM 23 in advance, and a communication line is opened. In the case of a local 5G network, private 5G network, or private LTE network, which are self-operated or dedicated networks, multiple profiles are installed in the communication terminal 2 in advance by a network administrator or an authorized user.

[0026] Local 5G refers to a self-operated 5G network built by companies or local governments for use within a limited area. 5G networks have three characteristics: high speed, large capacity, ultra-low latency, and multiple simultaneous connections. Because local 5G networks are self-operated, they can flexibly switch profiles and communicate using the appropriate APN information for a given area. Usable frequencies can be selected from Sub6 (4.6-4.9 GHz band) and millimeter wave (28.2-29.1 GHz band) allocated for local 5G use.

[0027] The APN information includes the name (access point name), APN name, user name, password, authentication type, etc. For example, if a subscriber is registered with carrier "A" among multiple carriers "A," "B," and "C," the access point name would be "a mobile," the APN name would be "a.ne.jp," the user name would be "a***," the password would be "***," and the authentication type would be "PAP or CHAP." Depending on the carrier, other information may also be set. Since APN information differs depending on the carrier, appropriate APN information should be stored. Registration of profile information may be performed using only the communication terminal 2, by displaying a QR code using another Wi-Fi®-compatible communication terminal other than the communication terminal 2 and reading the QR code, or by accessing an SM-DP+ server and installing the profile information. This method varies depending on the communication terminal manufacturer and model.

[0028] The procedure for switching profiles by user operation on the communication terminal 2 of FIG. 1 will be described below with reference to FIG.

[0029] First, when the user 1 performs a profile switching operation on the communication terminal 2 (step 201), the LPA application 21 receives a profile switching request (step 202). Next, the LPA application 21 notifies the modem control unit 22 of the received profile switching request.

[0030] Next, modem control unit 22 receives the profile switching request, performs profile switching processing, and registers communication terminal 2 on the network using the new profile information (step 203), thereby enabling user 1 to communicate using communication terminal 2 (step 204).

[0031] This profile switching process sequence is shown in Figure 3. That is, when user 1 performs a profile switching operation (step 301), a profile switching request is output to modem control unit 22 (step 302). Modem control unit 22 outputs the profile switching request to eSIM 23 (step 303), and performs profile switching within eSIM 23 (step 304). Modem control unit 22 receives a profile switching completion notification from eSIM 23 (step 305). Modem control unit 22 transmits the received profile switching completion notification to LPA application 21 (step 306).

[0032] Next, the modem control unit 22 executes an attach process, which is a process for registering the terminal information with the network (step 307). That is, the modem control unit 22 transmits an attach request to the external network 3 (step 308), and upon receiving an attach permission from the network 3 (step 309), transmits an attach completion to the network 3 (step 310).

[0033] By the above process, user 1 who owns communication terminal 2 is able to communicate via network 3 (step 311).

[0034] A typical profile switching procedure is shown in Figure 4. After completing the profile switching in the process shown in Figure 4, the modem control unit 22 starts the attach process. However, at this time, the modem control unit 22 is not notified of a change in APN (Access Point Name) information required for network connection, and the connection is rejected by the network 3, resulting in a long waiting time before communication becomes possible. The profile switching sequence shown in Figure 4 will now be described.

[0035] When user 1 performs a profile switching operation (step 401), the LPA application 21 outputs a profile switching request to the modem control unit 22 (step 402). The modem control unit 22 outputs the profile switching request to the eSIM 23 (step 403), and performs profile switching within the eSIM 23 (step 404). The modem control unit 22 receives a profile switching completion notification from the eSIM 23 (step 405). The modem control unit 22 transmits the received profile switching completion notification to the LPA application 21 (step 406).

[0036] Next, the modem control unit 22 sends an attach request to the network 3 using the APN information before the profile change (step 407). At this time, the APN information is different, so the attach request is rejected (step 408).

[0037] Thereafter, the LPA application 21 notifies the modem control unit 22 of the APN information after the profile change (step 409). The modem control unit 22 executes an attach process (step 410), which is a network registration process for the terminal information. That is, the modem control unit 22 transmits an attach request to the network 3 (step 411), and upon receiving an attach permission (registration permission) from the network 3 (step 412), transmits an attach completion (registration completion) to the network 3 (step 413).

[0038] Through the above process, user 1 having communication terminal 2 becomes able to communicate via network 3 (step 414). In the profile switching process of Fig. 4, it takes 10 seconds or more from the time of profile switching until communication becomes possible.

[0039] FIG. 5 is a sequence diagram of a high-speed processing of a network switching method in a communication terminal according to an embodiment of the present invention.

[0040] In the present invention, as shown in Fig. 5, when a profile switch occurs, the modem control unit 22 is notified of APN information stored in advance, and thereby the attach process is performed, thereby enabling quick network switching without being rejected by the network 3. The profile switch sequence in Fig. 5 will now be described.

[0041] When the user 1 performs a profile switching operation (step 501), the LPA application 21 notifies the modem control unit 22 of the APN information corresponding to the profile information after the switch, either before or simultaneously with the output of the profile switching request (step 502).

[0042] Next, the LPA application 21 outputs a profile switching request to the modem control unit 22 (step 503). The modem control unit 22 outputs a profile switching instruction to the eSIM 23 (step 504), and performs profile switching within the eSIM 23 (step 505). The modem control unit 22 receives a profile switching completion notification from the eSIM 23 (step 506). The modem control unit 22 transmits the received profile switching completion notification to the LPA application 21 (step 507).

[0043] The modem control unit 22 executes an attach process (step 508) that is a process of registering the terminal information to the network. That is, the modem control unit 22 transmits an attach request to the external network 3 using the received APN information after profile switching (step 509), and upon receiving an attach permission (registration permission) from the network 3 (step 510), transmits an attach completion (registration completion) to the network 3 (step 511).

[0044] Through the above process, user 1 who owns communication terminal 2 is able to communicate via network 3 (step 512). In the profile switching process of Fig. 5, it takes only a few seconds from profile switching until communication becomes possible.

[0045] In the above embodiment, a network switching method in a communication terminal that can quickly switch networks can be realized by using multiple profiles in the communication terminal 2 that uses the eSIM 23, and notifying the modem control unit 22 of APN information stored in advance from the LPA application 21 when a profile switch occurs, thereby performing an attach process that is a process of registering terminal information to the network without being rejected by the network 3. As a result, when multiple profiles are used in the communication terminal 2 that uses the eSIM 23, and profile switching is performed by a user operation, notifying the modem control unit 22 in advance of APN information after the profile switch makes it possible to quickly use the network after the profile switch.

[0046] In the above embodiment, an example has been described in which the profile switching process is performed in response to a profile switching operation by the user 1, but this is not limiting. For example, the above-described profile switching operation may be automatically performed by a robot equipped with the communication terminal 2 or a cybernetic avatar of the user 1.

[0047] <Example of Use in Which the Effects of the Invention are Most Effective> Figure 6 is an explanatory diagram illustrating automatic profile switching when moving from public 5G to local 5G according to an embodiment of the present invention. As shown in Figure 6, when a mobile object (e.g., a robot, an automated guided vehicle, etc.) equipped with a communication terminal 65 moves and automatically switches its profile from a public 5G area 62 covered by a public 5G base station 61 to a local 5G area 64 covered by a local 5G base station 63, the present invention is effective because automatic profile switching enables faster network availability than profile switching performed by a user's intentional operation. That is, in the public 5G area 62, the public 5G profile of the eSIM profile 66a in the communication terminal 65 is active. However, when the communication terminal 65 moves (67) and detects the local 5G area 64, the local 5G profile of the eSIM profile 66b in the communication terminal 65 is automatically switched to active, thereby achieving the effect of smooth wireless communication even when the mobile object moves.

[0048] 1 User 2 Communication terminal 3 Network 21 LPA application 22 Modem control unit 23 eSIM 61 Public 5G base station 62 Public 5G area 63 Local 5G base station 64 Local 5G area 65 Communication terminal 66a, 66b Profile 67 Communication terminal movement 81 eSIM operation system 82 Communication terminal 83 LPA application 84 eSIM 85 Terminal application 86 User 87 SM-DP+ server 91 Attach processing 201 Profile switching operation performed by user 202 Profile switching processing performed by LPA application 203 Network registration of new profile information by modem control unit 204 Communication terminal communication possible by user 301, 401, 501 Profile switching operation 302, 402, 503 Profile switching 303, 403, 504 Profile switching 304, 404, 505 Profile switching implemented 305, 405, 506 Profile switching completed 306, 406, 507 Profile switching completed 307, 410, 508 Attach process 308, 410 Attach request 309, 411, 509 Attach permission 310, 412, 510 Attach completed 311, 413, 511 Communication possible 407 Attach request 408 Attach denial 409 Notification of APN information after profile change 502 Notification of APN information corresponding to the profile after switching 509 Attach request (APN information after profile switching)

Claims

1. A network switching method for a communications terminal comprising: an eSIM (embedded SIM) that stores multiple profile information used for communications; an LPA (Local Profile Assistant) application that outputs a profile switching request in response to a user's profile switching operation; and a modem control unit that receives the profile switching request from the LPA application, switches the multiple profile information of the eSIM, notifies the LPA application of profile switching completion, and performs a process of registering terminal information to an external network, wherein the LPA application notifies the modem control unit of APN (Access Point Name) information corresponding to the profile information after switching before or simultaneously with outputting the profile switching request, and the modem control unit performs a process of registering terminal information to the external network using the received APN information after profile switching.

2. A network switching method in a communication terminal as described in claim 1, characterized in that the modem control unit sends a registration request to the external network using the APN information received after the profile switching, and when registration permission is received from the external network, performs registration processing of the terminal information by sending a registration completion to the external network.

3. A network switching method for a communication terminal according to claim 1 or 2, characterized in that the profile switching operation is automatically performed by a robot or a cybernetic avatar.

4. A network switching method in a communication terminal according to claim 1 or 2, wherein the APN information includes an access point name, an APN name, a user name, a password, and an authentication type.

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