Communication system, communication control method, and base station

Abstract

Provided are a communication system, a communication control method, and a base station with which it is possible to improve the security of communications employing a tethering function. The communication system comprises a base station, a terminal device which is capable of performing data communication with the base station, and which has a tethering function whereby a slave terminal device operates as a master terminal device that is communicatively connected to the base station, and the slave terminal device which is capable of utilizing a communication connection employing the tethering function of the terminal device, wherein at least the communication connection between the slave terminal device and the base station is suspended if the communication connection with the base station by the slave terminal device is not permitted.

Description

[Technical field]

[0001] The present invention relates to a communication system, a communication control method, and a base station. This application claims priority based on Japanese Patent Application No. 2021-115397 filed on July 13, 2021, the contents of which are incorporated herein by reference. [Background technology]

[0002] Conventionally, a system for performing information communication using a tethering function is known. For example, Patent Document 1 discloses a system in which a second communication device is communicatively connected to a communication network via a first communication device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6477223 Summary of the Invention [Problem to be solved by the invention]

[0004] In communication using the tethering function, a slave terminal device is communicatively connected to a master terminal device that performs data communication with a base station using the tethering function, and the slave terminal device can communicate with the base station via the master terminal device. However, for example, if a communication network provided by a base station is to be provided only to a specific user, a security risk occurs in that a third party other than the specific user can connect to the communication network using the tethering function. For example, the third party can connect a slave terminal device that is not permitted to be connected to the communication network to a master terminal device that is permitted to be connected to the communication network using the tethering function, and communication can be established between the slave terminal device that is not permitted to be connected to the communication network and the base station.

[0005] The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide a communication system, a communication control method, and a base station that can improve security in communication using a tethering function. [Means for solving the problem]

[0006] A communication system according to one embodiment of the present disclosure includes a base station, a terminal device capable of data communication with the base station and having a tethering function that operates as a parent terminal device for communicatively connecting a child terminal device to the base station, and the child terminal device that can utilize a communication connection using the tethering function possessed by the terminal device, and when a communication connection by the child terminal device with the base station is not permitted, at least the communication connection between the child terminal device and the base station is stopped.

[0007] A communication control method according to one embodiment of the present disclosure is a communication control method executed by a communication system including a base station, a terminal device capable of data communication with the base station and having a tethering function that operates as a parent terminal device for communicatively connecting a child terminal device to the base station, and the child terminal device that can utilize a communication connection using the tethering function possessed by the terminal device, and includes a step in which, when the child terminal device is not permitted to communicate with the base station, the base station or the terminal device stops the communication connection between at least the child terminal device and the base station.

[0008] A base station in one embodiment of the present disclosure is a base station equipped with a communication unit that transmits and receives radio signals used for data communication with a terminal device, and a control unit, wherein the terminal device has a tethering function that operates as a parent terminal device that communicatively connects a child terminal device to the base station, and when an attempt is made to establish a communication connection between the child terminal device and the base station via the terminal device using the tethering function, the control unit determines whether or not the child terminal device is permitted to establish a communication connection with the base station, and when the child terminal device is not permitted to establish a communication connection with the base station, executes control to at least stop the communication connection between the child terminal device and the base station. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating a schematic configuration of a communication system according to an embodiment. [Diagram 2] 2 is a functional block diagram showing an example of the configuration of the communication system of FIG. 1. [Diagram 3] 3 is a sequence diagram showing a first example of processing by the communication system of FIG. 2. [Figure 4] 4 is a sequence diagram showing a second example of the process performed by the communication system of FIG. 2. [Diagram 5] 2. FIG. 4 is a sequence diagram showing a third example of a process performed by the communication system of FIG. [Figure 6] 3 is a flowchart showing an example of a process executed by the base station of FIG. 2; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or equivalent components are denoted by the same reference numerals, and redundant descriptions of the same or equivalent components will be omitted as appropriate.

[0011] Fig. 1 is a diagram showing a schematic configuration of a communication system 1 according to an embodiment. As shown in Fig. 1, the communication system 1 includes a base station 10, a terminal device 20, a first terminal device 30, and a second terminal device 40.

[0012] The base station 10 provides a communication network by a predetermined wireless communication method. The predetermined wireless communication method may be a communication method using a fifth generation mobile communication system (5G system). For example, the predetermined wireless communication method may be local 5G. Local 5G is a method in which a 5G system is installed in a limited area by a cable operator, not a national mobile carrier, and data communication is performed wirelessly. However, the predetermined wireless communication method is not limited to local 5G, and may be other wireless communication methods including, for example, private LTE (Long Term Evolution) or private 5G. Private LTE may include, for example, regional BWA (Broadband Wireless Access) or sXGP. In this embodiment, the base station 10 provides a communication network by local 5G, and the following description will be given. When using the communication network by local 5G, the security of the communication network by local 5G can be improved by not connecting to an external network for communication.

[0013] The terminal device 20 is a terminal device capable of data communication with the base station 10. The terminal device 20 performs data communication with the base station 10 using a communication network provided by the base station 10. The terminal device 20 may be, for example, a router terminal, a smartphone, or a tablet terminal.

[0014] 1, only one terminal device 20 is illustrated, but in reality, the communication system 1 may include multiple terminal devices 20. The base station 10 can perform data communication with multiple terminal devices 20 within a communication coverage area A1 of the communication network.

[0015] In this embodiment, since the base station 10 provides a communication network by local 5G, only the terminal device 20 into which a SIM (Subscriber Identity Module) card registered in the base station 10 is inserted can perform data communication with the base station 10. Therefore, information on a SIM card that is inserted into the terminal device 20 to enable the terminal device 20 to perform data communication with the base station 10 is registered in the base station 10 in advance, for example, by being stored in the base station storage unit 12 described later. The base station 10 can limit the terminal device that performs data communication to only the terminal device 20 into which the registered SIM card is inserted, by any known method. For example, the base station 10 performs data communication with the terminal device 20 into which the registered SIM card is inserted, by performing authentication. The base station 10 prevents information communication with an external terminal device that does not have a SIM card registered in the base station 10 inserted, by performing data communication only with the terminal device 20 into which the SIM card registered in the base station 10 is inserted. This ensures security in the communication network.

[0016] The terminal device 20 has a tethering function. The tethering function is a function that operates as a parent terminal device that connects a child terminal device to the base station 10. That is, the terminal device 20 can operate as a parent terminal device in the tethering function. When operating as a parent terminal device, the terminal device 20 functions as an access point for the child terminal device. The terminal device 20 can establish communication with the child terminal device using the tethering function by any known connection method. In this embodiment, the terminal device 20 will be described below as establishing communication with the child terminal device using the tethering function by a Wifi (registered trademark) connection. However, the terminal device 20 may also establish communication with the child terminal device using the tethering function by a Bluetooth (registered trademark) connection or a USB (Universal Serial Bus) connection.

[0017] The first child terminal device 30 and the second child terminal device 40 are terminal devices that can utilize a communication connection using a tethering function of the terminal device 20. In other words, the first child terminal device 30 and the second child terminal device 40 are child terminal devices that can communicate with the terminal device 20 by the tethering function. The first child terminal device 30 and the second child terminal device 40 may be, for example, a computer, a smartphone, or a tablet terminal.

[0018] The first child terminal device 30 is a child terminal device that is permitted to communicate with the communication network provided by the base station 10. For example, the first child terminal device 30 is registered in advance with the base station 10. On the other hand, the second child terminal device 40 is a child terminal device that is not permitted to communicate with the communication network provided by the base station 10. Therefore, for example, the second child terminal device 40 is not registered with the base station 10. In the present specification, the fact that communication connection with the base station 10 is permitted is also simply expressed as "connection permitted." That is, in this embodiment, the first child terminal device 30 is permitted to connect with the base station 10, and the second child terminal device 40 is not permitted to connect with the base station 10.

[0019] 1, only one each of the first child terminal device 30 and the second child terminal device 40 is illustrated, but in reality, the communication system 1 may include a plurality of first child terminal devices 30 and second child terminal devices 40. That is, the terminal device 20 can communicate using the tethering function with a plurality of first child terminal devices 30 and second child terminal devices 40 that are within the area A2 in which communication is possible using the tethering function.

[0020] FIG. 2 is a functional block diagram showing an example of the configuration of the communication system 1 of FIG.

[0021] As shown in FIG. 2, the base station 10 includes a base station control unit 11, a base station storage unit 12, and a base station communication unit 13 as functional units.

[0022] The base station control unit 11 controls and manages the entire base station 10, including each functional unit of the base station 10. The base station control unit 11 includes at least one processor. The base station control unit 11 is configured with a processor such as a CPU (Central Processing Unit) that executes a program that defines a control procedure, or a dedicated processor specialized for processing each function. Note that the base station control unit 11 may be provided in a cloud that can communicate with the base station 10, instead of the base station 10, for example.

[0023] The base station control unit 11, for example, executes control of data communication between the base station 10 and the terminal device 20 into which a SIM card registered in the base station 10 is inserted. That is, the base station control unit 11 judges whether the terminal device 20 that is to execute data communication is a terminal device into which a SIM card registered in the base station 10 is inserted, and executes data communication with the terminal device 20 when it is determined that the terminal device is a terminal device into which a SIM card registered in the base station 10 is inserted. Information about the SIM card is stored in advance in, for example, the base station storage unit 12. When the base station control unit 11 receives information about the terminal device from the terminal device 20 that is to execute data communication, it refers to the information about the terminal device stored in the base station storage unit 12 and judges whether the SIM card registered in the base station 10 is inserted in the terminal device 20. When it is determined that the SIM card registered in the base station 10 is inserted in the terminal device 20, the base station control unit 11 executes data communication with the terminal device 20.

[0024] In this embodiment, when a communication connection between a slave terminal device and a base station 10 is to be established via a terminal device 20 using the tethering function, the base station control unit 11 determines whether or not the slave terminal device is permitted to communicate with the base station 10. In other words, when a terminal device 20 that performs data communication with the base station 10 uses the tethering function to communicate with a slave terminal device, the base station control unit 11 determines whether or not the slave terminal device is permitted to communicate with the communication network provided by the base station 10. The base station control unit 11 executes processing according to the result of the determination. Details of the processing executed by the base station control unit 11 will be described later.

[0025] The base station storage unit 12 is a storage medium capable of storing programs and data. The base station storage unit 12 can be configured with, for example, a semiconductor memory or a magnetic memory. The base station storage unit 12 may store, for example, a program for operating the base station 10. Similarly to the base station control unit 11, the base station storage unit 12 may be provided in, for example, a cloud capable of communicating with the base station 10, instead of the base station 10.

[0026] The base station storage unit 12 stores, for example, information on terminal devices permitted to establish a data communication connection with the base station 10 (hereinafter also referred to as "terminal information"). The terminal information is information capable of uniquely identifying a terminal device. The terminal information may be any information including, for example, an IMEI (International Mobile Equipment Identity) number or a serial number. The base station storage unit 12 stores, for example, a list of terminal information on terminal devices permitted to establish a data communication connection with the base station 10.

[0027] In this embodiment, the base station storage unit 12 stores, for example, information about a slave terminal device that is permitted to connect to a communication network provided by the base station 10. The information about the slave terminal device (hereinafter also referred to as "slave terminal information") is information that can uniquely identify the slave terminal device. The slave terminal information may be any information including, for example, an IMEI number or a serial number. The base station storage unit 12 stores, for example, a list of slave terminal information about slave terminal devices that are permitted to connect to a communication network provided by the base station 10.

[0028] The base station communication unit 13 transmits and receives data (radio signals) by wireless communication via an antenna. The radio signals are used for data communication with the terminal device 20. By transmitting and receiving data, data communication between the base station 10 and the terminal device 20 is performed. The data received by the base station communication unit 13 is subjected to predetermined processing by the base station control unit 11. The predetermined processing is well-known processing including, for example, AD conversion and Fourier transform. Furthermore, the base station communication unit 13 transmits the radio signals generated by the base station control unit 11 from the antenna.

[0029] As shown in FIG. 2, the terminal device 20 includes a terminal control unit 21, a terminal storage unit 22, a terminal communication unit 23, a terminal display unit 24, and a terminal input unit 25 as functional units.

[0030] The terminal control unit 21 controls and manages the entire terminal device 20, including each functional unit of the terminal device 20. The terminal control unit 21 includes at least one processor. The terminal control unit 21 is configured with a processor such as a CPU that executes a program that defines a control procedure, or a dedicated processor specialized for processing each function.

[0031] When the terminal device 20 uses the tethering function to communicate with a child terminal device, the terminal control unit 21 controls the processing of the communication using the tethering function. When the terminal device 20 uses the tethering function to communicate with a child terminal device, if the base station control unit 11 determines that the child terminal device is a second child terminal device 40 that is not permitted to be connected, the terminal control unit 21 may execute processing based on the determination result. Details of the processing executed by the terminal control unit 21 will be described later.

[0032] The terminal storage unit 22 is a storage medium capable of storing programs and data. The terminal storage unit 22 can be configured with, for example, a semiconductor memory or a magnetic memory. The terminal storage unit 22 may store, for example, a program for operating the terminal device 20. The terminal storage unit 22 may also store terminal information of the terminal device 20 that includes the terminal storage unit 22. For example, the terminal storage unit 22 may store an IMEI number or a serial number.

[0033] The terminal communication unit 23 transmits and receives data by wireless communication via an antenna. By transmitting and receiving data, data communication between the base station 10 and the terminal device 20 is performed. The data received by the terminal communication unit 23 is subjected to a predetermined process by the terminal control unit 21. The predetermined process is a known process including, for example, AD conversion and Fourier transformation. The terminal communication unit 23 transmits a wireless signal generated by the terminal control unit 21 from the antenna. When the terminal device 20 executes a communication connection with a child terminal device using a tethering function, the terminal communication unit 23 transmits, for example, a Wifi signal for a communication connection using the tethering function (hereinafter also referred to as a "tethering connection"). When communication using the tethering function is established by a USB connection, the terminal communication unit 23 may transmit and receive data by wired communication via a USB cable.

[0034] The terminal display unit 24 includes a display device such as a Liquid Crystal Display, an Organic Electro-Luminescence Panel, or an Inorganic Electro-Luminescence panel. The terminal display unit 24 displays characters, images, symbols, figures, and the like. The terminal display unit 24 may be configured as a touch screen display including not only a display function but also a touch screen function. In this case, the touch screen detects contact with the user's finger, a stylus pen, or the like of the terminal device 20.

[0035] The terminal input unit 25 accepts operation input from a user of the terminal device 20. The terminal input unit 25 is configured with, for example, operation buttons (operation keys). The terminal input unit 25 may be configured with a touch screen, and an input area for accepting operation input from the user may be displayed on a part of the display device that is the terminal display unit 24, to accept touch operation input from the user.

[0036] As shown in FIG. 2, the first child terminal device 30 includes, as functional units, a first control unit 31, a first storage unit 32, a first communication unit 33, a first display unit 34, and a first input unit 35.

[0037] The first control unit 31 controls and manages the entire first child terminal device 30, including each functional unit of the first child terminal device 30. The first control unit 31 includes at least one processor. The first control unit 31 is configured with a processor such as a CPU that executes a program that defines a control procedure, or a dedicated processor specialized for processing each function. The first control unit 31 controls the processing of communication using, for example, a tethering function.

[0038] The first storage unit 32 is a storage medium capable of storing programs and data. The first storage unit 32 can be configured with, for example, a semiconductor memory or a magnetic memory. The first storage unit 32 may store, for example, a program for operating the first child terminal device 30. The first storage unit 32 may also store child terminal information of the first child terminal device 30 that includes the first storage unit 32. For example, the first storage unit 32 may store an IMEI number or a serial number.

[0039] The first communication unit 33 transmits and receives data by wireless communication via an antenna. In this embodiment, the first communication unit 33 transmits and receives data by wireless communication using at least a tethering function. When communication using the tethering function is established by a USB connection, the first communication unit 33 may transmit and receive data by wired communication via a USB cable. The data received by the first communication unit 33 is subjected to a predetermined process by the first control unit 31. The predetermined process is a known process including, for example, AD conversion and Fourier transform.

[0040] The first display unit 34 includes a display device such as a liquid crystal display, an organic EL panel, or an inorganic EL panel. The first display unit 34 displays characters, images, symbols, figures, and the like. The first display unit 34 may be configured as a touch screen display including not only a display function but also a touch screen function. In this case, the touch screen detects contact with a finger, a stylus pen, or the like of the user of the first child terminal device 30.

[0041] The first input unit 35 accepts an operation input from the user of the first child terminal device 30. The first input unit 35 is configured by, for example, an operation button (operation key). The first input unit 35 may be configured by a touch screen, and an input area for accepting an operation input from the user may be displayed in a part of the display device that is the first display unit 34, to accept a touch operation input from the user.

[0042] 2, the second child terminal device 40 includes, as functional units, a second control unit 41, a second storage unit 42, a second communication unit 43, a second display unit 44, and a second input unit 45. The configurations and functions of the second control unit 41, the second storage unit 42, the second communication unit 43, the second display unit 44, and the second input unit 45 included in the second child terminal device 40 may be similar to those of the first control unit 31, the first storage unit 32, the first communication unit 33, the first display unit 34, and the first input unit 35 included in the first child terminal device 30, respectively. Therefore, detailed descriptions of the second control unit 41, the second storage unit 42, the second communication unit 43, the second display unit 44, and the second input unit 45 will be omitted here.

[0043] Next, a description will be given of an example of processing executed by the communication system 1. Fig. 3 is a sequence diagram showing a first example of processing by the communication system 1 of Fig. 2, and is a sequence diagram showing an example of a communication control method according to the present disclosure.

[0044] First, the base station 10 establishes a communication connection with the terminal device 20 through a communication network. In this embodiment, the base station 10 establishes a local 5G connection with the terminal device 20 (step S11). The base station 10 establishes a communication connection with the terminal device 20, for example, by authenticating a SIM card inserted into the terminal device 20 and confirming that the SIM card inserted into the terminal device 20 is a SIM card registered with the base station 10.

[0045] When a user of the terminal device 20 performs a predetermined input operation on the terminal device 20 to execute the tethering function, the terminal device 20 executes the tethering function. For example, the terminal device 20 transmits a Wifi signal for a tethering connection. The first child terminal device 30 receives, for example, the Wifi signal transmitted by the terminal device 20, and establishes a tethering connection with the terminal device 20 (step S12). Similarly, the second child terminal device 40 receives, for example, the Wifi signal transmitted by the terminal device 20, and establishes a tethering connection with the terminal device 20 (step S13).

[0046] When the terminal device 20 detects that a tethering connection with at least one child terminal device has been established, the terminal device 20 transmits a connection request signal using a tethering APN (step S14). The tethering APN is an access point name used when the terminal device 20 executes the tethering function. That is, in step S14, the terminal device 20 transmits a signal to the base station 10 requesting execution of a communication connection with the access point name that executes the tethering function.

[0047] The base station 10 can recognize that the terminal device 20 is executing the tethering function by receiving a connection request signal using the tethering APN from the terminal device 20.

[0048] When the base station 10 receives a connection request signal using the tethering APN from the terminal device 20, the base station 10 judges whether or not the child terminal device attempting to establish a communication connection with the base station 10 using the tethering function is a child terminal device permitted to be connected. The child terminal device attempting to establish a communication connection with the base station 10 using the tethering function is a child terminal device with which a tethering connection has been established with the terminal device 20, and in this example, is the first child terminal device 30 and the second child terminal device 40.

[0049] Specifically, the base station 10 determines whether or not the slave terminal device is permitted to communicate with the base station 10 based on whether or not the slave terminal device information of the slave terminal device that can use the communication connection using the tethering function is included in the slave terminal information stored in the base station storage unit 12. More specifically, the base station 10 determines whether or not the slave terminal device is permitted to communicate with the base station 10, for example, in steps S15, S20, and S21.

[0050] That is, when the base station 10 receives a connection request signal using the tethering APN from the terminal device 20, it transmits a signal requesting child terminal information to the terminal device 20 (step S15). Specifically, the base station 10 transmits a signal requesting child terminal information of a child terminal device with which the terminal device 20 establishes a communication connection by the tethering function. Here, the child terminal device with which the terminal device 20 establishes a communication connection by the tethering function is the first child terminal device 30 and the second child terminal device 40 with which the tethering connection is established by steps S12 and S13, respectively.

[0051] When the terminal device 20 receives a signal requesting the child terminal information from the base station 10, it transmits a signal requesting the child terminal information to all child terminal devices with which a tethering connection has been established with the terminal device 20. That is, in this example, the terminal device 20 transmits a signal requesting the child terminal information to the first child terminal device 30 (step S16). Similarly, the terminal device 20 transmits a signal requesting the child terminal information to the second child terminal device 40 (step S17). In steps S16 and S17, the terminal device 20 may transmit (transfer) the signal requesting the child terminal information received in step S15 to the first child terminal device 30 and the second child terminal device 40 as is, or may generate a new signal based on the signal requesting the child terminal information received in step S15 and transmit the new signal to the first child terminal device 30 and the second child terminal device 40.

[0052] In response to receiving a signal requesting the child terminal information from the terminal device 20, the first child terminal device 30 transmits the child terminal information of the first child terminal device 30 stored in the first storage unit 32 to the terminal device 20 (step S18). Similarly, in response to receiving a signal requesting the child terminal information from the terminal device 20, the second child terminal device 40 transmits the child terminal information of the second child terminal device 40 stored in the second storage unit 42 to the terminal device 20 (step S19).

[0053] The terminal device 20 transmits the child terminal information received from the child terminal device to the base station 10 (step S20). That is, in this example, the terminal device 20 transmits the child terminal information of the first child terminal device 30 and the second child terminal device 40 to the base station 10.

[0054] When the base station 10 receives the child terminal information from the terminal device 20, the base station 10 judges whether the child terminal device having the child terminal information is permitted to communicate with the base station 10. (Step S21). For example, the base station 10 judges whether the child terminal information received from the terminal device 20 is stored in the base station storage unit 12, thereby judging whether the communication connection with the base station 10 is permitted. That is, the base station 10 judges whether the child terminal information received from the terminal device 20 is included in a list of child terminal information related to the child terminal device permitted to connect, which is stored in the base station storage unit 12. If the child terminal information received from the terminal device 20 is included in the list, the base station 10 judges that the child terminal device of the child terminal information is permitted to communicate with the base station 10. Conversely, if the child terminal information received from the terminal device 20 is not included in the list, the base station 10 judges that the child terminal device of the child terminal information is not permitted to communicate with the base station 10.

[0055] When the base station 10 receives a plurality of pieces of child terminal information from the terminal device 20, in step S21, the base station 10 judges whether or not communication connection is permitted for a plurality of child terminal devices corresponding to the plurality of pieces of child terminal information. That is, in this case, the base station 10 judges whether or not each of the plurality of pieces of child terminal information is included in a list of child terminal information related to child terminal devices permitted for communication connection, stored in the base station storage unit 12. In this embodiment, since the base station 10 has received the child terminal information of the first child terminal device 30 and the second child terminal device 40, in step S21, the base station 10 judges whether or not communication connection is permitted for these two child terminal devices.

[0056] In this example, the child terminal information of the first child terminal device 30 is included in the list stored in the base station storage unit 12. Therefore, the base station 10 determines that the first child terminal device 30 is permitted to communicate with the base station 10. On the other hand, the child terminal information of the second child terminal device 40 is not included in the list stored in the base station storage unit 12. Therefore, the base station 10 determines that the second child terminal device 40 is not permitted to communicate with the base station 10.

[0057] In step S21, if the base station 10 determines that the communication connection of the child terminal device with the base station 10 is not permitted, the communication connection between at least the child terminal device and the base station 10 is stopped in the communication system 1. In this case, for example, the base station 10 executes control to stop the communication connection between at least the child terminal device and the base station 10. In this example, since it is determined that the communication connection of the second child terminal device 40 with the base station 10 is not permitted, the base station 10 executes control to stop the communication connection between at least the second child terminal device 40 and the base station 10.

[0058] 3, as a control for stopping the communication connection between at least the second child terminal device 40 and the base station 10, the base station 10 stops data communication with the terminal device 20 (step S22). As a result, the terminal device 20 cannot execute data communication with the base station 10, and therefore cannot execute communication between the child terminal device and the base station by the tethering function. Therefore, the communication connection between the second child terminal device 40 and the base station 10 is stopped.

[0059] In this case, data communication between the base station 10 and the terminal device 20 is stopped, and therefore the first child terminal device 30, which is permitted to establish a communication connection, cannot establish a communication connection with the base station 10 using the tethering function. However, to prevent the second child terminal device 40, which is not permitted to establish a communication connection, from illegally establishing a communication connection with the base station 10, the base station 10 may stop data communication with the terminal device 20 as shown in the first example.

[0060] If the base station 10 determines in step S21 that communication connections are permitted for all of the multiple child terminal devices corresponding to the received child terminal information, the base station 10 permits a connection request using the tethering APN by the terminal device 20 and causes the terminal device 20 to execute a communication connection using the tethering function. This allows the child terminal device to establish a communication connection with the base station 10 via the terminal device 20 functioning as the parent terminal device.

[0061] In the first example of the process shown in Fig. 3, the base station 10 has been described as stopping data communication with the terminal device 20 as the control for stopping the communication connection between at least the second child terminal device 40 and the base station 10. However, the control for stopping the communication connection between at least the second child terminal device 40 and the base station 10 is not limited to this. Other examples of the control for stopping the communication connection between at least the second child terminal device 40 and the base station 10 will be described as second and third examples of the process.

[0062] Fig. 4 is a sequence diagram showing a second example of processing by the communication system 1 of Fig. 2. In the processing of the second example shown in Fig. 4, steps S11 to S21 are similar to steps S11 to S21 of the first example described with reference to Fig. 3, and therefore detailed description thereof will be omitted here.

[0063] When the base station 10 determines in step S21 that the communication connection by the child terminal device with the base station 10 is not permitted, the base station 10 executes control for stopping at least the communication connection between the child terminal device and the base station 10. In the second example shown in FIG. 4, as control for stopping the communication connection between at least the second child terminal device 40 and the base station 10, the base station 10 transmits a signal (hereinafter also referred to as a "notification signal") notifying the terminal device 20 that the communication connection is not permitted (step S23). The base station 10 may transmit to the terminal device 20 the child terminal information of the child terminal device determined to be not permitted for communication connection, including the notification signal. In this example, the base station 10 transmits to the terminal device 20 the child terminal information of the second child terminal device 40 for which communication connection is not permitted, including the notification signal.

[0064] When the terminal device 20 receives the notification signal from the base station 10, it stops the tethering function (step S24). For example, the terminal device 20 may stop transmitting a Wifi signal for the tethering connection. For example, the terminal device 20 may disable data communication with the base station 10 using the tethering function. For example, the terminal device 20 may perform control so as not to authenticate data communicated using the tethering function. The terminal device 20 may stop the tethering function by a method other than the method shown here. When the terminal device 20 stops the tethering function, the communication connection between the second child terminal device 40 and the base station 10 is stopped.

[0065] In this case, the tethering function of the terminal device 20 itself is stopped, and therefore the first child terminal device 30, which is permitted to make a communication connection, cannot execute a communication connection with the base station 10 using the tethering function. However, in order to prevent the second child terminal device 40, which is not permitted to make a communication connection, from illegally executing a communication connection with the base station 10, as shown in the second example, the terminal device 20 may stop the tethering function.

[0066] Fig. 5 is a sequence diagram showing a third example of processing by the communication system 1 of Fig. 2. In the processing of the third example shown in Fig. 5, steps S11 to S21 are similar to steps S11 to S21 of the first example described with reference to Fig. 3, and therefore detailed description thereof will be omitted here.

[0067] When the base station 10 determines in step S21 that the communication connection by the slave terminal device with the base station 10 is not permitted, the base station 10 executes control for terminating at least the communication connection between the slave terminal device and the base station 10. In a third example shown in Fig. 5, a notification signal is transmitted to the terminal device 20 as control for terminating at least the communication connection between the second slave terminal device 40 and the base station 10 (step S23). Step S23 in the processing of the third example may be the same as step S23 in the processing of the second example.

[0068] When the terminal device 20 receives the notification signal from the base station 10, it stops the communication connection using the tethering function with the child terminal device for which the communication connection is not permitted (step S25). Specifically, the terminal device 20 identifies the child terminal device for which the communication connection is determined not to be permitted based on the child terminal information of the child terminal device for which the communication connection is determined not to be permitted, which is included in the communication signal. In this example, the second child terminal device 40 is identified as the child terminal device for which the communication connection is determined not to be permitted. The terminal device 20 stops the tethering connection with the identified second child terminal device 40. For example, the terminal device 20 may control so as not to assign an IP address to the child terminal device (here, the second child terminal device 40) indicated by the child terminal information included in the notification signal. For example, the terminal device 20 may control so as not to authenticate the data received from the second child terminal device 40. The terminal device 20 may stop the tethering connection with the second child terminal device 40 by a method other than the method shown here. When the terminal device 20 stops the tethering function with the second child terminal device 40, the communication connection between the second child terminal device 40 and the base station 10 is stopped.

[0069] In the third example, the terminal device 20 stops the tethering connection with the second child terminal device 40. Therefore, the tethering connection with the first child terminal device 30 is maintained. In other words, the first child terminal device 30 that is permitted to communicate can execute a tethering connection with the base station 10 using the tethering function. In this way, the communication system 1 can execute a tethering connection by the first child terminal device 30 that is permitted to communicate, while stopping the communication connection with the second child terminal device 40 that is not permitted to communicate.

[0070] As described above in the first to third examples, the communication connection between the second child terminal device 40 and the base station 10 may be stopped by either the base station 10 or the terminal device 20. In other words, when the communication connection between the second child terminal device 40 and the base station 10 is not permitted, it is sufficient that the base station 10 or the terminal device 20 at least stops the communication connection between the second child terminal device 40 and the base station 10.

[0071] FIG. 6 is a flowchart showing an example of a process executed by the base station 10 of FIG.

[0072] First, the base station 10 establishes a local 5G connection with the terminal device 20 (step S31). For example, as described with reference to step S11 in FIG. 3, the base station 10 authenticates the SIM card inserted in the terminal device 20 and confirms that the SIM card inserted in the terminal device 20 is a SIM card registered in the base station 10, thereby establishing a communication connection with the terminal device 20. After establishing the local 5G connection with the terminal device 20, the base station 10 can perform data communication with the base station 10 using a local 5G communication network.

[0073] The base station 10 determines whether or not a connection request signal using the tethering APN has been received from the terminal device 20 (step S32). For example, as described in step S14 of Fig. 3, the terminal device 20 can transmit a connection request signal using the tethering APN. When the terminal device 20 transmits the signal and the base station 10 receives the signal, the base station 10 determines in step S32 that the connection request signal using the tethering APN has been received.

[0074] When the base station 10 determines that a signal for a connection request using the tethering APN has not been received (No in step S32), the base station 10 repeats step S32 until it determines that a signal for a connection request using the tethering APN has been received.

[0075] When the base station 10 determines that a connection request signal using the tethering APN has been received (Yes in step S32), the base station 10 can recognize that a tethering connection between the terminal device 20 and the slave terminal device has been established (step S33).

[0076] In this case, the base station 10 transmits a signal requesting child device terminal information to the terminal device 20 (step S34). The signal transmitted in step S34 is the same as the signal described in step S15 of FIG.

[0077] As described in steps S16 to S20 of FIG. 3, the terminal device 20 that has received a signal requesting the child terminal information from the base station 10 acquires the child terminal information from the child terminal device with which a tethering connection has been established, and transmits the acquired child terminal information to the base station 10.

[0078] The base station 10 receives the child terminal information transmitted from the terminal device 20 (step S35).

[0079] Then, the base station 10 determines whether or not the slave terminal device having the slave terminal information is permitted to communicate with the base station 10 based on the received slave terminal information (step S36). Details of the process executed by the base station 10 in step S36 may be similar to the process described in step S21 of Fig. 3. That is, the base station 10 may refer to a list stored in the base station storage unit 12, for example, to determine whether or not the slave terminal device is permitted to communicate with the base station 10.

[0080] When the base station 10 determines that the child terminal device is permitted to communicate with the base station 10 (Yes in step S36), the base station 10 executes a communication connection with the child terminal device using a tethering function (step S37). As a result, a communication connection between the base station 10 and the child terminal device is executed via the terminal device 20 functioning as the parent terminal device.

[0081] On the other hand, when the base station 10 determines that the communication connection by the slave terminal device with the base station 10 is not permitted (No in step S36), the base station 10 executes control for stopping at least the communication connection between the slave terminal device and the base station 10 (step S38). The base station 10 can execute control for stopping the communication connection between the slave terminal device and the base station 10 by various methods. For example, as described in step S22 of FIG. 3, the base station 10 can stop the communication connection between the slave terminal device and the base station 10 by stopping data communication with the terminal device 20. For example, as described in step S23 of FIG. 4 and FIG. 5, the base station 10 may transmit a notification signal to the terminal device 20. In this case, the terminal device 20 that has received the notification signal stops the tethering function as described in step S24 of FIG. 4, or stops the tethering connection with the slave terminal device that is not permitted to be connected as described in step S25 of FIG. 5, thereby stopping the communication connection between the slave terminal device and the base station 10.

[0082] In the communication system 1 of the present embodiment, when a communication connection by a child terminal device with the base station 10 is not permitted, at least the communication connection between the child terminal device and the base station 10 is stopped. In the example shown in the present embodiment, since a communication connection by the second child terminal device 40 with the base station 10 is not permitted, at least the communication connection between the second child terminal device 40 and the base station 10 is stopped. This makes it possible to prevent the second child terminal device 40, which is not permitted to communicate with the base station 10, from making a communication connection with the base station 10 via the terminal device 20. Therefore, according to the communication system 1, it is possible to improve security in communication using the tethering function.

[0083] In the above embodiment, it has been described that the base station storage unit 12 of the base station 10 stores the child terminal information of the child terminal device permitted to be connected, and determines whether or not the child terminal device is permitted to communicate with the base station 10. However, the determination does not necessarily have to be performed by the base station 10. The determination may be performed, for example, by the terminal device 20. In this case, the terminal storage unit 22 of the terminal device 20 stores the child terminal information of the child terminal device permitted to be connected. For example, when a tethering connection with a child terminal device is established, the terminal device 20 may determine whether or not the child terminal information of the child terminal device is included in the child terminal information stored in the terminal storage unit 22, thereby determining whether or not the child terminal device is permitted to communicate with the base station 10. Therefore, the determination of whether or not the child terminal device is permitted to communicate with the base station 10 may be performed by at least one of the base station 10 and the terminal device 20.

[0084] In the above embodiment, an example of a case where a tethering connection is established by a Wifi connection has been described. However, the communication system 1 according to the present disclosure can also be applied to a case where a tethering connection is established by another connection method. For example, even when a tethering connection is established by a USB connection via a USB cable or a Bluetooth connection, if a communication connection between a slave terminal device and the base station 10 is not permitted, the communication connection between the slave terminal device and the base station 10 may be stopped.

[0085] In the above embodiment, it has been described that the base station 10 recognizes that a tethering connection between the terminal device 20 and the child terminal device has been established when the base station 10 receives a connection request signal using a tethering APN from the terminal device 20. However, the base station 10 may recognize that a tethering connection between the terminal device 20 and the child terminal device has been established by other methods. For example, the terminal device 20 may transmit a notification signal to the base station 10 to notify that a tethering connection between the terminal device 20 and the child terminal device has been established. In this case, the base station 10 can recognize that a tethering connection between the terminal device 20 and the child terminal device has been established by receiving the notification signal. This method is effective, for example, when the APN used when the terminal device 20 performs terminal communication without using the tethering function is the same as the APN used when the terminal device 20 performs tethering communication using the tethering function. The base station 10 may recognize that a tethering connection between the terminal device 20 and the child terminal device has been established by the data format of the data received from the terminal device 20.

[0086] In the above embodiment, a case has been described in which after a local 5G connection between the base station 10 and the terminal device 20 is established (step S11), a tethering connection between the terminal device 20 and the first child terminal device 30 and the second child terminal device 40 is established (steps S12 and S13). However, before a local 5G connection between the base station 10 and the terminal device 20 is established, a tethering connection between the terminal device 20 and the first child terminal device 30 and the second child terminal device 40 may be established. In this case, after a local 5G connection between the base station 10 and the terminal device 20 is established, the base station 10 may transmit a signal requesting child terminal information to the terminal device 20.

[0087] In the above embodiment, it has been described that the base station 10 determines whether or not the communication connection of the slave terminal device with the base station 10 is permitted based on the slave terminal information of the slave terminal device that is attempting to communicate with the base station 10 using the tethering function. The base station 10 may use a similar method to request terminal information from the terminal device 20 that functions as the master terminal device, and determine whether or not the communication connection of the terminal device 20 with the base station 10 is permitted based on the terminal information. When the base station 10 determines that the communication connection of the terminal device 20 with the base station 10 is not permitted, the base station 10 may stop data communication between the base station 10 and the terminal device 20 that is not permitted to be connected. This makes it possible to prevent, for example, a SIM card that is permitted for communication connection by local 5G provided by the base station 10 from being inserted and used in a terminal device that is not permitted to communicate with the base station 10.

[0088] Although the present disclosure has been described based on the drawings and embodiments, it should be noted that those skilled in the art can easily make various modifications and corrections based on the present disclosure. Therefore, it should be noted that these modifications and corrections are included in the scope of the present disclosure. For example, functions included in each functional unit or each step can be rearranged so as not to be logically inconsistent, and multiple functional units or steps can be combined or divided into one.

Claims

1. A base station; A terminal device capable of data communication with the base station and having a tethering function that operates as a parent terminal device that communicatively connects a child terminal device to the base station; a child terminal device that can use a communication connection using the tethering function of the terminal device; Equipped with the base station stores terminal information of a terminal device permitted to communicate with the base station; When the communication connection of the slave terminal device with the base station is not permitted, at least the communication connection between the slave terminal device and the base station is stopped. Communication systems.

2. A base station; A terminal device capable of data communication with the base station and having a tethering function that operates as a parent terminal device that communicatively connects a child terminal device to the base station; a child terminal device that can use a communication connection using the tethering function of the terminal device; Equipped with When the communication connection of the slave terminal device with the base station is not permitted, at least the communication connection between the slave terminal device and the base station is stopped; the base station, when the communication connection of the slave terminal device with the base station is not permitted, stops the data communication with the terminal device, thereby stopping the communication between the slave terminal device and the base station; Communication systems.

3. The communication system according to claim 1 , wherein the terminal device stops the communication connection between the slave terminal device and the base station by stopping the tethering function when the slave terminal device is not permitted to communicate with the base station.

4. The communication system according to claim 1, wherein when the child terminal device is not permitted to communicate with the base station, the terminal device stops the communication connection between the child terminal device and the base station by stopping the communication connection with the child terminal device using the tethering function.

5. The base station, determining whether or not the child terminal device capable of using the communication connection using the tethering function is permitted to communicate with the base station based on whether or not child terminal device information of the child terminal device capable of using the communication connection using the tethering function is included in the stored child terminal information; A communication system according to any one of claims 1 to 4.

6. The communication system according to claim 1 , wherein the base station provides the data communication by local 5G, private LTE (Long Term Evolution), or private 5G.

7. A base station; A terminal device capable of data communication with the base station and having a tethering function that operates as a parent terminal device that communicatively connects a child terminal device to the base station; a child terminal device that can use a communication connection using the tethering function of the terminal device; Equipped with A communication control method executed by a communication system in which the base station stores terminal information of a terminal device permitted to communicate with the base station, When the communication connection by the slave terminal device to the base station is not permitted, the base station or the terminal device stops the communication connection between at least the slave terminal device and the base station; A communication control method comprising:

8. A communication unit that transmits and receives radio signals used for data communication with a terminal device; A control unit; A base station comprising: the terminal device has a tethering function that operates as a parent terminal device that communicatively connects a child terminal device to the base station; The control unit is When a communication connection between the slave terminal device and the base station is to be established via the terminal device by the tethering function, determining whether or not the communication connection between the slave terminal device and the base station is permitted; When the communication connection by the slave terminal device to the base station is not permitted, at least a control is executed to stop the communication connection between the slave terminal device and the base station. Base station.

Images