JP2024064765A - COMMUNICATION DEVICE, CONTROL METHOD, AND PROGRAM - Google Patents

Abstract

[Problem] To realize stable communication with a specific information terminal via an access point (AP). [Solution] A communication device 10a includes a first communication IF 11 that connects to an AP 30a and wirelessly communicates with information terminals 40a to 40d via the AP 30a, a first acquisition unit 131 that acquires an image transmission start instruction to a display device 20a transmitted by the information terminal 40a, a determination unit 133 that determines whether the first communication IF 11 and the information terminal 40a are connected to different APs when the first acquisition unit 131 acquires the instruction, a connection control unit 134 that performs connection control to cause the first communication IF 11 to disconnect from the AP 30a and connect the first communication IF 11 to the AP 30b to which the information terminal 40a is connected when it is determined that they are connected to different APs, a second acquisition unit 132 that acquires image data from the information terminal 40a via the AP 30b when the above connection control is performed, and an output unit 135 that outputs the image data to the display device 20a. [Selected Figure] FIG.

Description

The present invention relates to a communication device, a control method, and a program.

For example, Patent Document 1 discloses a technology that performs communication control so that when two or more access points (APs) with the same wireless LAN (Local Area Network) identification information are found among a plurality of APs and a device attempts to connect to one of the APs, if the AP satisfies a predetermined condition (one example is "radio field strength lower than a threshold"), the device does not connect to the AP.

Patent No. 4833779

However, in the technology described in Patent Document 1, for example, when multiple access points have the same wireless LAN identification information, the device and information terminal may connect to an access point with a strong received signal among the multiple access points. Since these access points are connected to each other via a wired network, the communication path between the device and the information terminal may not be optimal depending on the access point to which the device and the information terminal are connected. In this case, communication bandwidth of a path that is not necessary for communication between the device and the information terminal may be consumed, and the communication error rate may increase.

The present invention has been made to solve the above problems, and aims to provide a communication device etc. that can perform stable communication with a specific information terminal via an access point.

In order to solve the above problem, a communication device according to one aspect of the present invention is a communication device including: a wireless communication interface that connects to an access point and wirelessly communicates with an information terminal via the access point; a first acquisition unit that acquires an instruction to start transmitting image data to a display unit, transmitted from a specific information terminal; a determination unit that, when the first acquisition unit acquires the instruction, determines whether the wireless communication interface and the specific information terminal are connected to different access points; a connection control unit that performs connection control to disconnect the wireless communication interface from the access point and connect the wireless communication interface to the access point to which the specific information terminal is connected, when the determination unit determines that the wireless communication interface and the specific information terminal are connected to different access points; a second acquisition unit that acquires the image data from the specific information terminal via the access point to which the specific information terminal is connected, when the connection control is performed by the connection control unit; and an output unit that outputs the image data acquired by the second acquisition unit to the display unit.

According to this, when the communication device is connected to an access point different from the access point to which a specific information terminal (i.e., an information terminal that has received a user's instruction and sent an instruction to start transmitting image data to itself) is connected, the communication device can switch the connection from the access point to which it is connected to the access point to which the specific information terminal is connected, and acquire image data from the specific information terminal. Therefore, the communication path between the communication device and the information terminal is shorter than in a state in which the communication device and the specific information terminal are each connected to different access points. This allows the communication device to perform stable communication (particularly image data communication) with the specific information terminal via the access point, and therefore can stably output image data to the display unit.

In addition, when the acquisition unit acquires the instruction, the acquisition unit may acquire, from the specific information terminal, device identification information of the access point to which the information terminal is connected, and the determination unit may determine whether the wireless communication interface and the specific information terminal are connected to different access points based on the device identification information acquired by the acquisition unit.

With this, when the communication device receives an instruction from a specific information terminal to start transmitting image data to the display unit, the communication device can also receive from the information terminal device identification information of the access point to which the specific information terminal is connected. In this way, the communication device can receive from the specific information terminal the instruction and the device identification information of the access point to which the information terminal is connected, and therefore can efficiently determine whether or not the communication device is connected to an access point different from the specific information terminal.

In addition, when the acquisition unit acquires the instruction, the acquisition unit may acquire device identification information of the access point to which the specific information terminal is connected from the access point, and the determination unit may determine whether the wireless communication interface and the specific information terminal are connected to different access points based on the device identification information acquired by the acquisition unit.

With this, when the communication device receives an instruction from a specific information terminal to start transmitting image data to the display unit, the communication device can obtain device identification information of the access point to which the specific information terminal is connected from the access point to which the specific information terminal is connected. In this way, the communication device can obtain the instruction from the specific information terminal and the device identification information of the access point to which the information terminal is connected, and therefore can efficiently determine whether or not the communication device is connected to an access point different from the specific information terminal.

The device identification information may also be a Basic Service Set Identifier (BSSID).

By using the BSSID as identification information for the access point, the communication device can distinguish between the access point to which it is connected and the access point to which a specific information terminal is connected, even when multiple access points are connected to a single network.

In addition, a control method according to one aspect of the present invention is a control method for a communication device, the control method including a wireless communication step of connecting the communication device to an access point and wirelessly communicating with an information terminal via the access point, a first acquisition step of acquiring an instruction transmitted from a specific information terminal to start transmitting image data to a display unit, a determination step of judging whether the communication device and the specific information terminal are connected to different access points when the instruction is acquired in the first acquisition step, a connection control step of disconnecting the communication device from the access point and connecting the communication device to the access point to which the specific information terminal is connected when it is determined in the determination step that the communication device and the specific information terminal are connected to different access points, a second acquisition step of acquiring the image data from the specific information terminal via the access point to which the specific information terminal is connected when the connection control is performed in the connection control step, and an output step of outputting the image data acquired in the second acquisition step to the display unit.

This provides the same effect as the above communication device.

A program according to one aspect of the present invention is a program that causes a computer to execute the above control method.

This provides the same effect as the above communication device.

The present invention can be realized not only as an apparatus, but also as a method in which the processing means constituting the apparatus are steps, as a program that causes a computer to execute those steps, as a computer-readable recording medium such as a CD-ROM on which the program is recorded, or as information, data, or signals that indicate the program. Furthermore, those programs, information, data, and signals may be distributed via a communications network such as the Internet.

The present invention allows a communication device to achieve stable communication with a specific information terminal via an access point.

FIG. 1 is a diagram illustrating an example of transmission and reception of image data between a communication device according to an embodiment and a specific information terminal. FIG. 2 is a first schematic diagram illustrating an example of a configuration of a communication system and a communication device according to an embodiment. FIG. 3 is a second schematic diagram illustrating an example of the configuration of the communication system and the communication device according to the embodiment. FIG. 4 is a flow diagram illustrating an example of a process executed by a communication device according to an embodiment. FIG. 5 is a sequence diagram illustrating an example of a process executed by the communication system according to the embodiment.

The following describes the embodiment in detail with reference to the drawings.

The embodiments described below each show a preferred embodiment of the present invention. The numerical values, shapes, materials, components, the position and connection of the components, steps, and the order of steps shown in the following embodiments are merely examples and are not intended to limit the present invention. Furthermore, among the components in the following embodiments, those components that are not described in the independent claims that show the highest concept of the present invention are described as optional components that make up a more preferred embodiment. Note that the same reference numerals are used to denote the same components, and descriptions may be omitted.

(Embodiment)
In this embodiment, a communication system and a communication device that can realize stable communication with an information terminal via an access point will be described.

First, a specific situation of sending and receiving image data between a communication device according to this embodiment and a specific information terminal will be described with reference to FIG. 1. FIG. 1 is a diagram showing an example of sending and receiving image data between a communication device according to this embodiment and a specific information terminal.

In this embodiment, the spaces 50a and 50b are school classrooms, and an example is described in which a teacher uses the information terminal 40a in the space 50a (here, the classroom) and students use the information terminals 40b, 40c, and 40d to conduct a lesson, but the example is not limited to this.

In the example of FIG. 1, communication device 10a and display device 20a are connected by wire, and communication device 10b and display device 20b are connected by wire. In the following, an example in which the communication device and the display device are separate will be described, but the communication device and the display device may be integrated. In this case, the display device may function as a display unit provided in the communication device.

In addition, access point 30a and access point 30b have the same wireless LAN identification information (SSID) and are connected to each other via a wired network N. The reason for using the same SSID across different spaces (classrooms) within the school is that students may move to different classrooms to take classes, not just one classroom, and teachers may move to multiple classrooms to teach their own subjects. In that case, if the SSID is different for each classroom when kitting multiple information terminals, it would be necessary to set the SSIDs for all classrooms in advance on all information terminals, which would be extremely cumbersome.

In FIG. 1, communication device 10a is performing wireless communication with multiple information terminals 40a-40d present in space 50a in which communication device 10a is installed via access point 30a (in other words, wirelessly connected). Note that communication device 10a performing wireless communication with multiple information terminals 40a-40d via one access point 30a means that communication device 10a is wirelessly connected to each of the multiple information terminals 40a-40d via at least one access point 30a to which communication device 10a is connected.

(a) of FIG. 1 is a diagram showing an example of image data transmission and reception when a communication device 10a and an information terminal 40b (a so-called specific information terminal) that has received an instruction from a user to start transmitting image data to a display device 20a (hereinafter also referred to as an image transmission start instruction) are connected to the same access point 30a. When the information terminal 40b receives an image transmission start instruction from a user to the display device 20a, it transmits an image transmission start instruction to the communication device 10a via the access point 30a. When the communication device 10a receives an image transmission start instruction from the information terminal 40b to the display device 20a, it determines whether the communication device 10a and the information terminal 40b are connected to different access points. In this example, since both the communication device 10a and the information terminal 40b are connected to the access point 30a, the communication device 10a obtains image data from the information terminal 40b via the access point 30a and outputs the obtained image data to the display device 20a.

In FIG. 1B, the specific information terminal that has received an image transmission start instruction from the user to the display device 20a is the information terminal 40a, and the communication device 10a and the information terminal 40a are connected to different access points. When the information terminal 40a receives an image transmission start instruction from the user to the display device 20a, it transmits an image transmission start instruction to the communication device 10a via the access point 30b. In general, if the access point 30a in the space 50a and the access point 30b in the space 50b adjacent to the space 50a have the same SSID, each of the multiple information terminals 40a to 40d in the space 50a connects to the access point with the strongest received signal strength. Therefore, depending on the positions of the information terminals 40a to 40d in the space 50a, there may be an information terminal that connects to the access point 30b installed in the space 50b, like the information terminal 40a. In this example, the communication device 10a is connected to the access point 30a. When image data is transmitted and received between the communication device 10a and the information terminal 40a under such connection conditions, the communication device 10a obtains the image data transmitted from the information terminal 40a via the access point 30b, the wired network N, and the access point 30a. In this way, the communication device 10a consumes communication bandwidth of a route that is not necessary for image data communication with the information terminal 40a, which may increase the communication error rate.

In this invention, when the communication device 10a receives an image transmission start instruction from the information terminal 40a to the display device 20a under such a connection situation, the communication device 10a determines that the information terminal 40a and the communication device 10a are connected to different access points, and switches the access point to which the communication device 10a is connected. In other words, if the access point to which the information terminal that issued the image transmission start instruction is connected is different from the access point to which the communication device 10a is connected, the communication device 10a switches the access point to which the communication device 10a is connected. More specifically, as shown in FIG. 1B, the communication device 10a disconnects the communication device 10a from the access point 30a and connects to the access point 30b to which the information terminal 40a is connected. The communication device 10a then obtains image data from the information terminal 40a via the access point 30b, and outputs the obtained image data to the display device 20a.

Next, a communication system and a communication device according to the present embodiment will be described with reference to Figs. 2 and 3. Fig. 2 is a first schematic diagram showing an example of the configuration of a communication system and a communication device according to the present embodiment. Fig. 3 is a second schematic diagram showing an example of the configuration of a communication system and a communication device according to the present embodiment. Note that the dashed lines in Figs. 2 and 3 indicate connection paths via wireless communication.

In this embodiment, the communication system 100 includes, for example, a communication device 10a and two or more access points (for example, access points 30a and 30b) connected to each other via a wired network N. Here, an example in which the communication system 100 includes the communication device 10a and the access points 30a and 30b will be described, but the present invention is not limited to this example.

Access points 30a and 30b have the same wireless LAN identification information (SSID) and are installed in different spaces. For example, as shown in FIG. 2, access point 30a is installed in space 50a, and access point 30b is installed in space 50b.

In one space, one communication device, one display device, and one access point are installed, and the access points installed in each space are connected to each other by a wired network N. For example, as shown in FIG. 2, in space 50a, a communication device 10a, a display device 20a, and an access point 30a are installed, and there are multiple information terminals 40a, 40b, 40c, and 40d used by multiple users. In space 50b, a communication device 10b, a display device 20b, and an access point 30b are installed. In addition, when the communication device and the display device are integrated, one communication device having a display unit and one access point are installed in one space. The display unit may be realized, for example, by a display panel. The display panel is, for example, a liquid crystal panel or an organic EL (Electro Luminescence), etc.

The spaces 50a and 50b are, for example, spaces separated by a wall or a partition within a building. The spaces 50a and 50b may be adjacent spaces or may face each other across an aisle or the like. For example, the building may be a school, an office building, an event hall, or a hospital, and the space may be a classroom, a seminar room, a meeting room, or a conference room.

The communication device 10a is a communication device that transmits image data acquired from, for example, one of the information terminals 40a to 40d (so-called a specific information terminal) to the display device 20a. More specifically, when the communication device 10a acquires an instruction to start transmitting image data to the display device 20a from one of the information terminals 40a to 40d (so-called an image transmission start instruction), the communication device 10a connects to the same access point as the access point to which the information terminal is connected, acquires image data from the information terminal, and outputs the image data to the display device 20a. In the following, an embodiment of the present disclosure will be described with the information terminal 40a as a specific information terminal. For example, when the communication device 10a acquires an image transmission start instruction from the information terminal 40a to the display device 20a, the communication device 10a disconnects the connection between the first communication interface 11 and the access point 30a (see FIG. 2) and connects the first communication interface 11 to the access point 30b (see FIG. 3). The image data may be still image data or moving image (video) data.

In this embodiment, an example in which the communication device and the display device are separate will be described, but the present invention is not limited to this example, and the communication device and the display device may be integrated (in one housing). In this case, the communication device 10a includes a display unit as one of its functional configurations, and therefore the second communication interface 12 may not be required.

The communication device 10a includes, for example, a first communication interface 11 (first communication IF in the figure), a second communication interface 12 (second communication IF in the figure), a control unit 13, and a memory unit 14.

The first communication interface 11 is an example of a wireless communication interface of the present disclosure. More specifically, the first communication interface 11 is a communication circuit (or a communication module) that connects to the access point 30a and performs wireless communication with a plurality of information terminals 40a to 40d via the access point 30a. Furthermore, when the determination unit 133 described later determines that the first communication interface 11 and a specific information terminal (e.g., the information terminal 40a in FIG. 2) that has accepted an instruction to start image transmission to the display device 20a are connected to different access points, the first communication interface 11 disconnects from the access point 30a and connects to the access point (e.g., the access point 30b) to which the information terminal 40a is connected. The first communication interface 11 performs wireless communication with the access points 30a and 30b.

The second communication interface 12 is a communication circuit (or a communication module) that connects to the display device 20a. More specifically, the second communication interface 12 is a connection terminal for connecting to the display device 20a via a wired cable. For example, the second communication interface 12 includes a video input/output terminal such as an HDMI (registered trademark) (High-Definition Multimedia Interface) connection terminal or a DVI (Digital Visual Interface) connection terminal.

The control unit 13 performs various information processing related to the communication device 10a. The control unit 13 is realized, for example, by a microcomputer, but may also be realized by a processor or a dedicated circuit. The functions of the control unit 13 are realized by hardware such as a microcomputer or processor constituting the control unit 13 executing a computer program (software) stored in the memory unit 14.

The control unit 13 includes, as functional components, a first acquisition unit 131, a second acquisition unit 132, a determination unit 133, a connection control unit 134, and an output unit 135. Specific processes performed by the first acquisition unit 131, the second acquisition unit 132, the determination unit 133, the connection control unit 134, and the output unit 135 will be described later.

The memory unit 14 is a storage device in which computer programs executed by the control unit 13 and the like are stored. The memory unit 14 can also temporarily store information that needs to be stored due to information processing performed by the first communication interface 11, the second communication interface 12, and the control unit 13. The memory unit 14 is realized, for example, by a HDD (Hard Disk Drive), but may also be realized by a semiconductor memory.

When the communication device 10b receives an image transmission start instruction from one information terminal (so-called a specific information terminal) among multiple information terminals (not shown) in the space 50b in which the communication device 10b is installed to the display device 20b, the communication device 10b connects to an access point to which the information terminal is connected, obtains image data from the information terminal, and outputs the image data to the display device 20b. The communication device 10b has a similar configuration to the communication device 10a, but differs from the communication device 10a in the following points. For example, the first communication interface 11 of the communication device 10b is a communication circuit (or a communication module) that connects to the access point 30b and performs wireless communication with the information terminal (not shown) via the access point 30b. The second communication interface 12 of the communication device 10b is a communication circuit (or a communication module) that connects to the display device 20b. The control unit 13 of the communication device 10b performs various information processing related to the communication device 10b.

The display device 20a acquires image data output from the communication device 10a and displays an image based on the acquired image data. The display device 20a has a display panel such as a liquid crystal panel or an organic EL (Electro Luminescence) panel. The display device 20a may be a monitor or a television. The display device 20b is similar to the display device 20a, but differs from the display device 20a in that it acquires image data output from the communication device 10b.

The access point 30a is a relay device that relays data communication between the communication device 10a and multiple information terminals 40a to 40d in the space 50a in which the access point 30a is installed. The access point 30a is connected to other access points (e.g., access point 30b) via a wired network N.

The access point 30b is basically a relay device that relays data communication between the communication device 10b and multiple information terminals in the space 50b in which the access point 30b is installed, but as shown in FIG. 1, for example, it may also relay data communication between an information terminal in a space surrounding the space 50b (e.g., space 50a) and a communication device (e.g., communication device 10a).

The multiple information terminals 40a to 40d are used by multiple users in one space (here, space 50a), for example. As described above, if space 50a is a school classroom, for example, information terminal 40a is a terminal used by a teacher teaching in the classroom, and information terminals 40b to 40d are terminals used by students. Information terminals 40a to 40d are, for example, personal computers, tablet terminals, or smartphones. Note that, although this embodiment will be described using information terminals 40a to 40d shown in FIG. 1, the number of information terminals is not limited to this.

Next, an example of the process executed by the communication device 10a according to the present embodiment will be described with reference to FIG. 4. FIG. 4 is a flow diagram showing an example of the process executed by the communication device 10a according to the present embodiment. Note that the process that branches depending on the condition will be described in detail in the explanation of each process.

As shown in FIG. 4, in the first communication step S01, the first communication interface 11 of the communication device 10a connects to the access point 30a and wirelessly communicates with the multiple information terminals 40a to 40d via the access point 30a (see FIG. 2 and FIG. 3). More specifically, for example, when the communication device 10a receives a connection command from a specific application of the multiple information terminals 40a to 40d used by multiple users (e.g., teachers and students) staying in the space 50a in which the communication device 10a is installed, the communication device 10a wirelessly communicates with the multiple information terminals 40a to 40d via the access point 30a to which the communication device 10a is connected (not shown). Note that the wireless communication between the communication device 10a and the multiple information terminals 40a to 40d may be performed, for example, via the access point 30a, or may be performed directly without going through the access point 30a.

Next, in the second communication step S02, the second communication interface 12 of the communication device 10a connects to the display device 20a. As a result, for example, when the first communication interface 11 receives a connection command to the display device 20a from a specific application of the information terminal 40a operated by a user (e.g., a teacher), the communication device 10a transmits a response signal to the information terminal 40a via the first communication interface 11, and becomes able to receive (acquire) data of an image to be displayed on the display device 20a via the second communication interface 12. Note that, when the communication device and the display device are integrated, the display device functions as a display unit provided in the communication device, so the second communication interface 12 may not be provided. In this case, the control unit 13 of the communication device is connected to the display unit via a communication line (control line). Note that the second communication step S02 may be performed in parallel with the first communication step S01, or may be performed before the first communication step S01.

Next, in the first acquisition step S03, the first acquisition unit 131 of the communication device 10a acquires an instruction to start transmitting image data to the display device 20a (so-called an image transmission start instruction) sent by the information terminal 40a. For example, as shown in FIG. 1, the first acquisition unit 131 of the communication device 10a acquires the image transmission start instruction from the information terminal 40a to the display device 20a via the access point 30b.

Here, the communication device 10a acquires device identification information of the access point to which the information terminal 40a that sent the image transmission start instruction to the communication device 10a is connected. Unlike wireless LAN identification information (SSID), the device identification information is identifier information that can individually identify each access point, such as a BSSID. For example, the information terminal 40a may include the device identification information of the access point 30b to which it is connected in the image transmission start instruction to the display device 20a and transmit it, or may transmit the device identification information of the access point 30b together with the image transmission start instruction. In this case, when the first acquisition unit 131 of the communication device 10a acquires the image transmission start instruction to the display device 20a, it acquires the device identification information of the access point 30b to which the information terminal is connected from the information terminal 40a.

Also, for example, the information terminal 40a may transmit only an instruction to start image transmission to the display device 20a to the communication device 10a via the access point 30b. At this time, the access point 30b to which the information terminal 40a is connected may transmit its own identification information to the communication device 10a when relaying the image transmission start instruction from the information terminal 40a to the communication device 10a. In this case, when the first acquisition unit 131 of the communication device 10a acquires the image transmission start instruction to the display device 20a, it acquires the device identification information of the access point transmitted from the access point 30b to which the information terminal 40a is connected.

Next, in the judgment step S04, when an image transmission start instruction to the display device 20a is acquired in the first acquisition step S03, the judgment unit 133 of the communication device 10a judges whether the device itself and the information terminal 40a are connected to different access points. More specifically, the judgment unit 133 of the communication device 10a judges whether the device itself (first communication interface 11) and the information terminal 40a are connected to different access points based on the device identification information acquired in the first acquisition step S03. More specifically, for example, the judgment unit 133 of the communication device 10a judges whether the device identification information of the access point transmitted from the information terminal 40a differs from the device identification information of the access point 30a to which the device itself is connected. As a result, the judgment unit 133 of the communication device 10a judges whether the device itself and the information terminal 40a are connected to different access points. In addition, when the device identification information of the access point 30b to which the information terminal 40a is connected is included in the image transmission start instruction to the display device 20a, the determination unit 133 of the communication device 10a may obtain the device identification information by extracting the device identification information of the access point 30b from the image transmission start instruction.

Next, in the connection control step S05, the connection control unit 134 of the communication device 10a selects an access point to which the device should connect, depending on the result determined in the determination step S04. More specifically, in the connection control step S05, if it is determined in the determination step S04 that the device (first communication interface 11) and the information terminal 40a are connected to different access points, the connection control unit 134 of the communication device 10a disconnects the connection between the device (first communication interface 11) and the access point 30a, and controls the device (first communication interface 11) to connect to the access point 30b to which the information terminal 40a is connected. This control is also called connection control. The access point 30b is another access point among two or more access points that is different from the one access point to which the communication device 10a is connected, and is the access point to which the information terminal 40a that sent the image transmission start instruction to the communication device 10a is connected. Note that if it is determined in determination step S04 that the device itself (first communication interface 11) and the information terminal 40a are connected to the same access point, the connection control unit 134 does not perform the above control.

Next, in a second acquisition step S06, the second acquisition unit 132 of the communication device 10a acquires image data from the information terminal 40a via the access point 30b. As described above, the image data may be still image data or moving image data.

Next, in an output step S07, the output unit 135 of the communication device 10a outputs the image data acquired in the second acquisition step S06 to the display device 20a.

Next, an example of a process executed by the communication system 100 according to the embodiment will be described with reference to FIG. 5. FIG. 5 is a sequence diagram showing an example of a process executed by the communication system 100 according to the embodiment.

As shown in FIG. 5, when the information terminal 40a receives an instruction to start transmitting image data to the display device 20a (so-called an image transmission start instruction) input by the user (step S11), the information terminal 40a transmits the image transmission start instruction to the communication device 10a via the access point (AP) (steps S12, S13).

First, a case will be described in which the information terminal 40a transmits an instruction to start image transmission to the display device 20a via the access point 30b to the communication device 10a. Note that the communication device 10a is assumed to be connected to the access point 30a when it receives the instruction to start image transmission.

The information terminal 40a includes the device identification information of the access point 30b to which the information terminal 40a is connected in an image transmission start instruction and transmits it to the access point 30b (step S12). The access point 30b transmits the image transmission start instruction acquired from the information terminal 40a to the communication device 10a (step S13).

The information terminal 40a may send only the image transmission start instruction to the access point 30b to which the information terminal 40a is connected, without including the device identification information of the access point 30b to which the information terminal 40a is connected in the image transmission start instruction to the display device 20a. In this case, when the access point 30b receives the image transmission start instruction from the information terminal 40a to the display device 20a, the access point 30b may send the device identification information of the information terminal 40a to the communication device 10a together with the image transmission start instruction.

When the first acquisition unit 131 of the communication device 10a acquires an instruction to start image transmission to the display device 20a (step S14), the first acquisition unit 131 acquires device identification information of the access point 30b to which the information terminal 40a is connected (step S15). The processing of steps S14 and S15 was explained in the first acquisition step S03 of FIG. 4, so the explanation thereof will be omitted here.

Next, the determination unit 133 of the communication device 10a determines whether the communication device 10a (first communication interface 11) and the information terminal 40a are connected to different access points (step S16). More specifically, for example, the determination unit 133 determines whether the device identification information of the access point 30b to which the information terminal 40a is connected, which is acquired by the first acquisition unit 131 in step S15, is different from the device identification information of the access point 30a to which the communication device 10a is connected. In this case, since the device identification information of the two access points 30a and 30b is different, the determination unit 133 determines that the communication device 10a and the information terminal 40a are connected to different access points (Yes in step S16). Note that step S16 corresponds to the determination step S04 in FIG. 4.

Next, based on the determination unit 133 determining that the communication device 10a (first communication interface 11) and the information terminal 40a are connected to different access points (Yes in step S16), the connection control unit 134 of the communication device 10a performs control to disconnect the first communication interface 11 of the communication device 10a from the access point 30a (step S17) and connect the first communication interface 11 to the access point 30b to which the information terminal 40a is connected (step S18). As a result, the communication device 10a disconnects the connection between itself and the access point 30a and connects to the access point 30b to which the information terminal 40a is connected. Note that steps S17 and S18 correspond to the connection control step S05 in FIG. 4.

Next, after the above-mentioned connection control is performed by the connection control unit 134, the control unit 13 of the communication device 10a causes the information terminal 40a to transmit a signal requesting image data (hereinafter, image data request) to the first communication interface 11 (step S19). When the access point 30b receives the image data request from the communication device 10a, it transmits the image data request to the information terminal 40a (step S20).

Next, when the information terminal 40a receives a request for image data from the communication device 10a via the access point 30b (step S21), it transmits the image data to the communication device 10a via the access point 30b (steps S22, S23).

The second acquisition unit 132 of the communication device 10a acquires image data from the information terminal 40a via the access point 30b (step S24). Note that step S24 corresponds to the second acquisition step S06 in FIG. 4.

The output unit 135 of the communication device 10a outputs the image data acquired by the second acquisition unit 132 in step S24 to the display device 20a via the second communication interface 12 (step S25). Note that step S25 corresponds to the output step S07 in FIG. 4.

The display device 20a acquires the image data output by the output unit 135 of the communication device 10a in step S25, and displays an image based on the acquired image data (step S26).

Next, a case will be described in which the information terminal 40a transmits an image transmission start instruction to the communication device 10a via the access point 30a. It is assumed that the communication device 10a is connected to the access point 30a when it receives the image transmission start instruction.

The information terminal 40a includes the device identification information of the access point 30a to which the information terminal 40a is connected in the image transmission start instruction and transmits it to the access point 30a (step S12). The access point 30a transmits the image transmission start instruction acquired from the information terminal 40a to the communication device 10a (step S13).

The information terminal 40a may transmit only an image transmission start instruction to the access point 30a. In this case, when the access point 30a receives an image transmission start instruction from the information terminal 40a, the access point 30a may transmit the instruction together with its own device identification information to the communication device 10a.

When the first acquisition unit 131 of the communication device 10a acquires an instruction to start image transmission to the display device 20a (step S14), the determination unit 133 acquires device identification information of the access point 30a to which the information terminal 40a is connected (step S15).

Next, the determination unit 133 of the communication device 10a determines whether the communication device 10a (first communication interface 11) and the information terminal 40a are connected to different access points (step S16). More specifically, the determination unit 133 determines whether the device identification information of the access point 30a to which the information terminal 40a is connected, which was acquired in step S15, differs from the device identification information of the access point 30a to which the communication device 10a is connected. In this case, since the device identification information of these two access points 30a is the same, the determination unit 133 determines that the communication device 10a and the information terminal 40a are not connected to different access points (in other words, connected to the same access point) (No in step S16).

Next, if the determination unit 133 determines that the communication device 10a (first communication interface 11) and the information terminal 40a are not connected to different access points (i.e., connected to the same access point) (No in step S16), the control unit 13 of the communication device 10a causes the information terminal 40a to transmit a signal requesting image data (a so-called image data request) to the first communication interface 11 (step S19). When the access point 30a receives the image data request from the communication device 10a, it transmits the image data request to the information terminal 40a (step S20).

Next, when the information terminal 40a receives a request for image data from the communication device 10a via the access point 30a (step S21), it transmits the image data to the communication device 10a via the access point 30a (steps S22, S23).

The second acquisition unit 132 of the communication device 10a acquires the image data from the information terminal 40a via the access point 30a (step S24).

The output unit 135 of the communication device 10a outputs the image data acquired by the second acquisition unit 132 in step S24 to the display device 20a via the second communication interface 12 (step S25).

The display device 20a acquires the image data output by the output unit 135 of the communication device 10a in step S25, and displays an image based on the acquired image data (step S26).

As described above, in the embodiment of the present invention, the communication device determines whether the access point to which the device itself is connected is different from the access point to which the communication terminal that sent the image transmission start instruction to the communication device is connected, and if it determines that the two are different, it switches the access point to which the device itself is connected to the access point to which the communication terminal is connected. As a result, the communication device and the information terminal that sent the image transmission start instruction to the communication device are connected via the same access point, which eliminates unnecessary communication between different access points and shortens the communication path. As a result, the communication device can perform stable communication (particularly image data communication) with the information terminal via the access point, and can stably output image data to the display device 20a.

As exemplified in the above-mentioned embodiment, the present invention is a means for solving problems that occur in a system in which a communication device can connect to any of a plurality of access points. A typical example of such a system is a system in which the wireless LAN identification information (SSID) of a plurality of access points is set to be the same, but the present invention is not limited to this. Even if the wireless LAN identification information (SSID) of a plurality of access points is different, the present invention is useful. For example, if a communication device can store a plurality of SSIDs, it can use the SSID (part of the profile) stored in the device for each classroom to establish a wireless connection based on the SSID of the access point installed in the classroom. However, even in this case, the tendency of the information terminal to connect to an access point with strong radio wave strength (i.e., easy wireless connection) remains unchanged, so the information terminal may communicate with the communication device through an unintended communication path (for example, via an access point in an adjacent classroom).

In the above embodiment, the communication device 10a and the display device 20a are described as separate devices, but the two devices may have the same housing and may be arranged on the same board. The communication device 10a is a communication device that transmits image data acquired from an information terminal to the display device 20a, but is not limited to this example. For example, the communication device 10a may be a device that outputs image data acquired from an information terminal as a printout or data, such as a printer or scanner. The communication device 10a may also be a document camera. In this case, the communication device 10a may transmit the captured image data to the information terminal via an access point. At this time, when the information terminal acquires an instruction to display image data from the communication device 10a, it may acquire identification information of the access point to which the communication device 10a is connected, select the access point to which the communication device 10a is connected as the access point to which the communication device 10a is connected as the access point to which the communication device 10a is connected as the access point to which the communication device 10a is connected with priority, and acquire image data via the access point.

The present invention can be realized not only as an apparatus, but also as a method in which the processing means constituting the apparatus are steps, as a program that causes a computer to execute those steps, as a computer-readable recording medium such as a CD-ROM on which the program is recorded, or as information, data, or signals that indicate the program. Furthermore, those programs, information, data, and signals may be distributed via a communications network such as the Internet.

The communication device, control method, and program of the present invention have been described above based on the embodiment, but the present invention is not limited to this embodiment. As long as it does not deviate from the spirit of the present invention, various modifications conceivable by those skilled in the art to this embodiment and forms constructed by combining components of different embodiments are also included within the scope of the present invention.

The present invention can be used in communication devices that achieve stable communication with information terminals via access points.

REFERENCE SIGNS LIST 10a, 10b Communication device 11 First communication interface 12 Second communication interface 13 Control unit 131 First acquisition unit 132 Second acquisition unit 133 Determination unit 134 Connection control unit 135 Output unit 14 Storage unit 20a, 20b Display device 30a, 30b Access point 40a, 40b, 40c, 40d Information terminal 50a, 50b Space 100 Communication system N Wired network

Claims (6)

a wireless communication interface that is connected to an access point and wirelessly communicates with an information terminal via the access point;
a first acquisition unit that acquires an instruction to start transmitting image data to a display unit, the instruction being transmitted from a specific information terminal;
a determination unit that determines, when the first acquisition unit acquires the instruction, whether the wireless communication interface and the specific information terminal are connected to different access points;
a connection control unit that performs connection control to disconnect the wireless communication interface from the access point and connect the wireless communication interface to the access point to which the specific information terminal is connected when the determination unit determines that the wireless communication interface and the specific information terminal are connected to different access points;
a second acquisition unit that acquires the image data from the specific information terminal via an access point to which the specific information terminal is connected when the connection control unit has performed the connection control;
an output unit that outputs the image data acquired by the second acquisition unit to the display unit;
Equipped with
Communication device. When the first acquisition unit acquires the instruction, the first acquisition unit acquires, from the specific information terminal, device identification information of an access point to which the specific information terminal is connected;
the determination unit determines whether or not the wireless communication interface and the specific information terminal are connected to different access points based on the device identification information acquired by the first acquisition unit.
The communication device according to claim 1 . When the first acquisition unit acquires the instruction, the first acquisition unit acquires device identification information of the access point to which the specific information terminal is connected from the access point;
the determination unit determines whether or not the wireless communication interface and the specific information terminal are connected to different access points based on the device identification information acquired by the first acquisition unit.
The communication device according to claim 1 . The device identification information is a Basic Service Set Identifier (BSSID).
A communication device according to claim 2 or 3. A method for controlling a communication device, comprising:
a wireless communication step of connecting the communication device to an access point and wirelessly communicating with an information terminal via the access point;
A first acquisition step of acquiring an instruction to start transmitting image data to a display unit, the instruction being transmitted from a specific information terminal;
a determination step of determining whether or not the communication device and the specific information terminal are connected to different access points when the instruction is acquired in the first acquisition step;
a connection control step of performing connection control for disconnecting the communication device from the access point and connecting the communication device to the access point to which the specific information terminal is connected when it is determined in the determination step that the communication device and the specific information terminal are connected to different access points;
a second acquisition step of acquiring the image data from the specific information terminal via an access point to which the specific information terminal is connected when the connection control is performed in the connection control step;
an output step of outputting the image data acquired in the second acquisition step to the display unit;
including,
Control methods. A program causing a computer to execute the control method according to claim 5.

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