Intercom system

Abstract

To provide an intercom system that posts image data at an entrance to enable a visitor to call a resident using a device carried by the visitor based on the image data, and moreover that can maintain security.SOLUTION: An intercom system includes a mobile terminal 10 equipped with a camera 11 and carried by a visitor, a communication terminal 20 operated by a resident, a server 40 that manages communication between the two, and image data 30 posted at an entrance. The server 40 includes a call destination information storage unit 41 that stores the association between the image data 30 and a specific communication terminal 20, and a face detection unit 48 that detects a face. The mobile terminal 10 accesses the server 40 based on information of the image data 30, and obtains from the server 40 web information for calling the communication terminal 20 associated with the image data 30, thereby making it possible to call the communication terminal 20. The server 40 requests transmission of a captured image of the visitor's face in conjunction with transmission of the web information, and permits to call the communication terminal 20 if the face can be recognized from the transmitted image.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an intercom system in which a visitor can call a resident, and more particularly to an intercom system in which a visitor can call a resident without providing an intercom device for calling at the entrance.

Background Art

[0002] In an intercom system for calling a resident, an intercom handset for calling a resident is installed at the entrance, and an intercom master unit for responding to a call is installed inside the dwelling unit. When a visitor operates the intercom handset to make a call, the intercom master unit emits a ringing sound, and when the resident operates the intercom master unit to respond, a call can be made with the visitor.

[0003] On the other hand, in recent years, mobile terminals such as mobile phones have become popular, and it has become common for visitors to carry mobile terminals when visiting. In view of this situation, a technology for using a mobile terminal instead of an intercom handset has been considered. For example, Patent Document 1 discloses a technology for a system that notifies a person in charge when a visitor arrives at a company or the like. A QR code (registered trademark) is placed at the reception area of a company or the like, and when a visitor captures the QR code (registered trademark) with a mobile terminal, the person in charge can be called. This is configured such that when the mobile terminal accesses the server by reading the QR code (registered trademark), web information associated with the QR code (registered trademark) is returned from the server and displayed, and when the visitor performs an input operation such as entering a passcode according to this display, a notification of a visitor is made to the terminal of the person in charge of the visited destination. In this way, it is not necessary to install a device for calling such as an intercom handset at the reception area.

[0004] Also, in Cited Document 1, the server obtains the position information of the mobile terminal called by the call operation based on GPS information, and performs a process of not accepting a call from a location completely different from the reception area. By adding such a restriction, the occurrence of calls not related to subsequent misoperations by visitors is prevented.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The technology disclosed in the above Patent Document 1 can eliminate the equipment for calling at the reception place of enterprises and the like, so that cost reduction can be achieved. However, when considering the application of this technology to an intercom in a general household, the restriction based on the GPS location information may malfunction indoors, and GPS spoofing is possible. Therefore, the presence of malicious visitors or mischievous people cannot be ignored, and it is necessary to construct a further security improvement mechanism.

[0007] Therefore, in view of such problems, the present invention aims to provide an intercom system that can post image data at the entrance instead of the intercom sub-unit, and can call the resident with the device carried by the visitor based on this image data, and can maintain security.

Means for Solving the Problems

[0008] In order to solve the above problems, the configuration of the present invention is an intercom system having a mobile terminal carried by a visitor having a function of communicating with an external device via a public communication network, a communication terminal operated by a resident having a function of communicating with the mobile terminal via the public communication network, and a server for managing communication between the mobile terminal and the communication terminal. Image data for calling the communication terminal using the mobile terminal is posted at the entrance. The mobile terminal has a call function, a camera, and a function of reading the image data by imaging with the camera. Further, the server has a call destination information storage unit for storing the association between the image data and a specific communication terminal, a face detection unit for detecting a face from the captured image of the visitor by the camera, and a face image storage unit for storing the face image transmitted from the mobile terminal. When the mobile terminal reads the image data, it accesses the server based on the information of the image data, obtains Web information for calling the communication terminal associated with the image data from the server, and can call the communication terminal from the Web information. On the other hand, in accordance with the transmission of the Web information, the server makes a request to transmit the captured image of the visitor's face. If the face can be recognized from the image transmitted from the mobile terminal by this request, the image is saved and the call of the communication terminal by the mobile terminal is permitted using the Web information. If the face cannot be recognized from the transmitted image, the use of the Web information is made unavailable and the communication terminal cannot be called, which is characterized by this. According to this configuration, the visitor can use the mobile terminal carried by himself / herself to image the image data posted at the entrance, so that the resident can be called. Therefore, even if there is no intercom device at the entrance, the resident can be called. Moreover, since the visitor's face image is transmitted and saved when making a call operation, even if a call is made by a suspicious person or the like, the visitor can be identified from the saved face image, which is useful for maintaining security.

[0009] Another aspect of the present invention is that, in the above configuration, the server has an SSID information storage unit that associates a specific access point with each communication terminal and stores the SSID information thereof. When the server transmits web information to the mobile terminal that has received access, the server obtains the SSID information received by the mobile terminal from the mobile terminal. If the SSID stored in association with the communication terminal is not included in the obtained information, the server does not permit the mobile terminal to call the communication terminal based on the web information. According to this configuration, if the SSID received by the mobile terminal does not include the one associated with the communication terminal of the resident, the call is not permitted. That is, if the SSID information is a signal transmitted from the vicinity of the destination household, the resident cannot be called even if the web information is obtained unless the user is near the destination household. Therefore, malicious calls and prank calls can be prevented.

[0010] Another aspect of the present invention is that, in the above configuration, the web information transmitted from the server to the mobile terminal includes password information that is valid only once. By using the password, the mobile terminal can call the communication terminal. Once a communication path is formed between the mobile terminal and the communication terminal, the password becomes invalid and the call is no longer possible. According to this configuration, the call of the resident by the operation of reading the image data can be made only once, and subsequent calls are not possible. Therefore, pranks can be prevented.

Effects of the Invention

[0011] According to the present invention, a visitor can use a mobile terminal carried by the visitor to capture the image data posted on the entrance door, so that the resident can be called. Therefore, the resident can be called even without an intercom device at the entrance door. Moreover, since the face image of the visitor is transmitted and stored when the visitor makes a call operation, even if a call is made by a suspicious person or the like, the visitor can be identified from the stored face image, which helps to maintain security.

Brief Description of the Drawings

[0012]

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Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments embodying the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram showing an example of an intercom system 1 according to the present invention, including a mobile terminal 10 carried by a visitor, a communication terminal 20 possessed by a resident or installed in a living unit H, image data (two-dimensional code information) 30 posted at the entrance of the living unit for obtaining information of the communication terminal 20, a server 40 arranged on the cloud (on a public communication network N), and the like.

[0014] Figure 2 shows a functional block diagram of the mobile terminal 10. As shown in Figure 2, the mobile terminal 10 includes a camera 11, a display 12 for displaying various information, an operation unit 13 equipped with call buttons / end call buttons, etc., a memory 14 for storing received information and application software (hereinafter simply referred to as "app"), a communication unit 15, a wireless communication interface (wireless communication IF) 16 for wirelessly communicating with other devices via a public communication network N, etc., and a mobile terminal CPU 17 for controlling these components. The wireless communication IF 16 has an antenna for wirelessly connecting to the public communication network N or performing short-range wireless communication such as Bluetooth (registered trademark) and Wi-Fi with nearby devices, and performs data transmission and reception with a server 40, etc. via the public communication network N. The data to be transmitted and received is, for example, video data, text data, and program data.

[0015] The image data 30 is, for example, a QR code (registered trademark), and has information that enables access to the communication terminal 20 of the destination via the public communication network N, and is posted on the entrance wall or entrance door so that the visitor can capture it with a camera. By the visitor capturing the image with the camera 11 of the mobile terminal 10 and importing the information, the URL information of the server 40, etc. is read. Note that the image data 30 is not limited to a QR code (registered trademark), and may be a bar code or a numerical sequence. Also, the public communication network N is, for example, the Internet or a telephone line.

[0016] An app for reading the URL of the server 40 by capturing the posted image data 30 with the camera 11 of the mobile terminal 10 and accessing the read URL is pre-installed on the mobile terminal 10. When the image data 30 is read by this app, it accesses the server 40, and a web page, which is web information associated with the destination household H from the server 40, is transmitted.

[0017] The display 12 is composed of an LCD and displays video, images, and character information. Also, the operation unit 13 consists of a touch panel and is integrated with the display 12, enabling various operations including call operations. The mobile terminal 10 can be, for example, a multifunctional mobile phone (smartphone), but it can also be a tablet terminal.

[0018] FIG. 3 shows a block diagram of the communication terminal 20. As shown in FIG. 3, the communication terminal 20 includes a display 21 for displaying various information, an operation unit 22 for performing various operations including a call button for responding to calls, a memory 23 for storing received information and applications, a call unit 24, a camera 25, a communication interface (communication IF) 26 for communicating with other devices wirelessly or wired via a public communication network N, etc., and a communication terminal CPU 27 for controlling these components. As the communication terminal 20, a device carried and used by a resident such as a multifunctional mobile phone (smartphone) can be used, but it can also be a personal computer or a general-purpose tablet terminal. Furthermore, it can be a dedicated terminal fixedly installed indoors. By installing a predetermined application and registering the user with the server 40 through a predetermined operation, even a general-purpose terminal can function as the communication terminal 20. In addition, in FIG. 1, it is a multifunctional mobile phone.

[0019] FIG. 4 shows a block diagram of the server 40. As shown in FIG. 4, the server 40 includes a call destination information storage unit 41 for storing the association information between the image data 30 and the communication terminal 20 corresponding to each individual household, a call management unit 42 for storing the conditions for restricting calls, an SSID information storage unit 43 for storing the association between the communication terminal 20 and the SSID of a wireless LAN access point (hereinafter simply referred to as "access point"), an image data generation unit 45 for generating the image data 30, a face detection unit 48 for detecting a face from the image, a face storage unit (face image storage unit) 49 for storing the face image, a server CPU 47 for controlling these components, a server communication interface (server communication IF) 46 for communicating with external devices via a public communication network, etc.

[0020] The SSID of the access point registered (stored) in the server 40 is preferably the SSID of the access point installed in the destination household, but may also be the SSID of the access point installed near the destination household. However, it is assumed that an access point is installed at a location where the registered SSID can be received by the mobile terminal 10 where the image data 30 is posted.

[0021] In the called party information storage unit 41, the association between the image data 30 of a plurality of households H and the communication terminal 20 is registered and stored. Also, information regarding the resident is associated and stored together with the information of the communication terminal 20.

[0022] The server CPU 47 receives an access from the mobile terminal 10 that has read the image data 30, selects the communication terminal 20 associated with the image data 30, that is, selects the communication terminal 20 of the destination household H, and performs control to return to the mobile terminal 10 a web page for calling the selected communication terminal 20. However, it is determined whether the accessed mobile terminal 10 satisfies a predetermined condition, and if the condition is not satisfied, control is performed so that even if the mobile terminal 10 performs a calling operation of the communication terminal 20 based on the web page, it cannot be called.

[0023] Here, the image data 30 will be described. When the communication terminal 20 is registered, the server 40 generates user-specific image data 30 in the image data generation unit 45. This data is transmitted to the communication terminal 20. The resident who has thus obtained the image data 30 prints it or the like and posts it at the entrance. The URL information of the server 40 is registered in this image data 30. When a visitor captures the image data 30 with the camera 11 of the mobile terminal 10, the mobile terminal 10 reads the information, recognizes the URL of the server 40 and performs an access operation, and transmits it to the server 40 together with the information of the image data 30 for identifying the communication terminal 20.

[0024] The operation of the intercom system 1 configured as described above (the calling operation by the visitor and the response operation by the resident) is performed as follows. FIG. 5 is an operation transition diagram from when the mobile terminal 10 reads the image data 30 until a call is made and further a call is made, and will be described with reference to this FIG. 5. Here, a case will be described in which control for restricting a call is performed according to two conditions regarding face image transmission and SSID information. This condition setting is stored and managed in the call management unit 42.

[0025] When a visitor who has come to the front door of the destination residence takes an image with the mobile terminal 10 that carries the image data 30 posted on the front door, the installed application reads the image data 30 and accesses the URL destination included in the read information. That is, it accesses the server 40 (S1).

[0026] The server 40 that has received the access from the mobile terminal 10 returns Web information (Web page) for calling the communication terminal 20 of the call destination associated with the image data 30 based on the information of the image data 30 transmitted from the mobile terminal 10 (S2). Specifically, it transmits the top page of the Web page for calling the communication terminal 20. The mobile terminal 10 that has received the Web page from the server 40 displays the Web page (S3). In addition, the server 40, in accordance with the transmission of this Web page, based on the conditions set in the call management unit 42, transmits a command for requesting the SSID information of the access point received by the mobile terminal 10 and a command for activating the camera 11 of the mobile terminal 10.

[0027] FIG. 6 is an explanatory display diagram of the Web page thus received by the mobile terminal 10. As shown in FIG. 6, operation information indicating that the camera 11 is activated to capture a face is displayed (S3) on the display 12 together with the call button B1. When the displayed call button B1 is pressed (touched) (S4), the captured video of the camera 11 is transmitted to the server 40 together with a call signal. Here, the flow of transmitting the captured video of the camera 11 from the mobile terminal 10 is described, but a still image (captured image) may be transmitted. Also, based on the command, the SSID information received by the mobile terminal 10 is transmitted (S5) to the server 40. At this time, if a plurality of SSIDs are received, these plurality of SSID information (a list of SSIDs) are transmitted.

[0028] At the server 40 where the imaging video of the camera 11 and the SSID information are transmitted together with the call signal, the server CPU 47 makes the following determination. First, the face detection unit 48 determines whether the transmitted video is an imaging video of a face (S6). If a face is detected from the video, it is saved in the face storage unit 49. If a face cannot be detected, the imaging video (image) is requested again or the call control is terminated. When requesting again, for example, a message such as "A face could not be detected. Please take another picture and press the call button" is displayed on the mobile terminal 10, and the retransmission is awaited.

[0029] If a face is detected, next, it is checked whether there is an SSID registered in the SSID information storage unit 43 and associated with the communication terminal 20 to be called in the transmitted SSID list (S7). If there is a registered SSID, since two conditions are satisfied, the call is permitted and a call signal is transmitted to the communication terminal 20 (S8). If there is no registered SSID in the list, the call signal is not transmitted to the communication terminal 20 and the call control is terminated. In addition, when the call control is terminated without satisfying the conditions, a message indicating that the call cannot be made is transmitted to and displayed on the mobile terminal 10.

[0030] Thus, when a call signal is transmitted to the communication terminal 20, the server 40 transmits a second page of the web page to the mobile terminal 10 and causes the displayed web page to be updated to the page during the call (S9). FIG. 7 shows the display 12 of the mobile terminal 10 that displays the second page of the transmitted web page. As shown in FIG. 7, "During call" is displayed and a guiding message is displayed.

[0031] On the other hand, the communication terminal 20 that has received the call signal enters the called state and performs a call operation (S10). This call operation is performed in a different manner from other calls so that it can be recognized as a call from a visitor by an application installed to function as an intercom. For example, a message such as "There is a call from the entrance" is displayed on the display 21. By this display or the like, the resident can recognize that it is a call from a visitor to the home before responding.

[0032] After that, when the call button (not shown) of the communication terminal 20 is pressed (S11) and a response operation is performed, the server 40 permits the call (S12), a call path is formed between the mobile terminal 10 and the communication terminal 20, and a call becomes possible (S13) between the visitor and the resident.

[0033] When the call path is formed, under the control of the application installed in the server 40, the camera 11 of the mobile terminal 10 and the camera 25 of the communication terminal 20 are activated, and the captured image of the responding resident is displayed on the display 12 of the mobile terminal 10. The "During Call" display area E1 in FIG. 7 is a video display unit, and the face image of the resident received from the communication terminal 20 is displayed in this display area E1.

[0034] On the other hand, the face image of the visitor received from the mobile terminal 10 is also displayed on the display 21 of the communication terminal 20. Thus, the call is carried out while seeing the other party. After that, when the resident performs an end call operation on the communication terminal 20 or the visitor performs an end call operation on the mobile terminal 10, the server 40 cuts off the call path, and both devices return to the standby state.

[0035] In this way, the visitor can use the mobile terminal 10 carried by himself / herself to capture the image data 30 posted at the entrance, so that the resident can be called even if there is no intercom device at the entrance. Moreover, since the face image of the visitor himself / herself is transmitted and saved when the call operation is performed, even if a call is made by a suspicious person or the like, the visitor can be identified from the saved face image, which helps to maintain security. Also, if none of the SSIDs received by the mobile terminal 10 are associated with the communication terminal 20 of the resident, the call is not permitted. That is, if the information of the registered SSID is a signal transmitted from the visited household or its vicinity, if not near the visited household, even if the web page is obtained, the resident cannot be called. Therefore, malicious calls and mischievous calls can be prevented.

[0036] Next, another form of the intercom system 1 will be described. In the above form, in addition to registering the visitor's face image, the condition of the SSID is added to maintain security, but a limit based on the number of calls may also be added. Here, a configuration will be described in which, in combination with the registration of the face image, the use of a one-time password restricts the call to once. FIG. 8 shows the form of the intercom system 1 and shows a block diagram of the server 40. Since the configuration of the entire system, the configurations of the mobile terminal 10 and the communication terminal 20 are the same as those in the above form, the description thereof will be omitted. As shown in FIG. 8, the server 40 includes a called party information storage unit 41 that stores the association between the image data 30 and the communication terminal 20, a call management unit 42 that stores conditions for providing a limit to the call, an image data generation unit 45 that generates the image data 30, a face detection unit 48, a face storage unit (face image storage unit) 49 that stores the face image, a server communication interface (server communication IF) 46 that communicates with an external device via a public communication network, and a server CPU 47 that controls these.

[0037] FIG. 9 is an operation transition diagram from the call operation of this system to a call, and the operation will be described with reference to FIG. 9. When a visitor who has come to the visited household takes an image of the image data 30 posted at the entrance with the mobile terminal 10 carried, the installed application reads the image data 30 and accesses the URL destination included in the read information. That is, it accesses the server 40 (S101).

[0038] Upon receiving access from the mobile terminal 10, the server 40 returns (S102) Web information (Web page) for calling the communication terminal 20 of the called party associated with the image data 30 based on the information of the image data 30 transmitted from the mobile terminal 10. Specifically, it transmits the top page of the Web page for calling the communication terminal 20. At that time, based on the conditions set in the call management unit 42, that is, the two conditions of face image transmission and one-time password, the Web page is transmitted. Specifically, a Web page having a password input section and with the password described is transmitted. In the call management unit 42, the password generated by the server CPU 47 is stored in association with the communication terminal 20. In addition, the server 40 transmits a command to activate the camera 11 of the mobile terminal 10 in accordance with the transmission of this Web page.

[0039] The mobile terminal 10 that has received the Web page from the server 40 displays the Web page (S103). In addition, the mobile terminal 10 that has received the command activates the camera 11 in accordance with the received command.

[0040] FIG. 10 is an explanatory display diagram showing the Web page received by the mobile terminal 10 in this way. As shown in FIG. 10, on the display 12, a password input section B2 and a call button B3 are displayed, together with a guidance display for inputting the password, a display of a one-time valid password, and a guidance display indicating that the camera 11 is activated to capture a face. When, in accordance with the display, the presented password is input (S104) and the call button B3 is pressed (touch operation) (S105), the password input to the call signal is attached, and further, the captured video of the camera 11 is transmitted to the server 40.

[0041] In addition, when the password input section B2 is touched, a numeric keypad or the like is displayed, and the password can be input. Here, the flow is to transmit the captured video of the camera 11 from the mobile terminal 10, but a still image (captured image) may be transmitted.

[0042] At the server 40 where the password and the captured video of the camera 11 are transmitted (S106) together with the outgoing signal, the server CPU 47 controls as follows based on the conditions of the call management unit 42. If a face is detected in the transmitted video, the password is correct, and it is the first call (S107), the call is permitted and an outgoing signal is transmitted to the communication terminal 20 (S108). If no face is detected, or if the password is incorrect or it is an outgoing operation after a call path has been formed once, no outgoing signal is transmitted to the communication terminal 20. In this case, if no face can be detected, a retransmission request (requesting re - shooting and re - pressing the outgoing button) may be prompted, or if the password is incorrect, re - input may be prompted.

[0043] When the call is thus permitted and an outgoing signal is transmitted to the communication terminal 20, the server 40 transmits the second page of the web page to the mobile terminal 10 and updates (S109) the displayed web page to the page during the call. At this time, a web page similar to FIG. 7 is displayed. The communication terminal 20 that has received the outgoing signal enters the called state and performs an outgoing operation (S110). This outgoing operation is performed in a different manner from other calls so that it can be recognized that it is a call from a visitor. By this display, etc., the resident can recognize that it is a call from a visitor to the home before answering.

[0044] After that, when the call button (not shown) of the communication terminal 20 is pressed (S111) and a response operation is performed, the server 40 permits the call (S112), a call path is formed between the mobile terminal 10 and the communication terminal 20, and a call becomes possible (S113) between the visitor and the resident. When the server 40 performs call permission control, it then disables the use of the password and prohibits subsequent calls using the mobile terminal.

[0045] When a call path is formed, under the control of the application installed on the server 40, the camera 11 of the mobile terminal 10 and the camera 25 of the communication terminal 20 are activated, and the imaging video of the resident responding is displayed on the display 12 of the mobile terminal 10. On the other hand, the face video of the visitor received from the mobile terminal 10 is also displayed on the display 21 of the communication terminal 20. In this way, the call is carried out while seeing the other party. After that, when the resident performs an end call operation on the communication terminal 20 or the visitor performs an end call operation on the mobile terminal 10, the server 40 cuts off the call path, and all devices return to the standby state.

[0046] In this way, the visitor can use the mobile terminal 10 carried by himself / herself to capture the image data 30 posted at the entrance, so that the resident can be called. Therefore, even if there is no intercom device at the entrance, the resident can be called. In addition, since the face image of the visitor is transmitted and saved when performing the call operation, even if a suspicious person or the like makes a call, the visitor can be identified from the saved face image, which helps to maintain security. Also, by using a one-time password, once the call path is formed, subsequent calls cannot be made, so malicious visits and pranks can be prevented.

[0047] In addition, in each of the above embodiments, the conditions for permitting a call are set by adding other conditions to the registration of the face image, but only the registration of the face image may be sufficient, which is effective for maintaining security. Also, the three conditions of face image storage, the SSID of the access point, and the one-time password may be implemented together.

Explanation of Signs

[0048] 1... Intercom system, 10... Mobile terminal, 11... Camera, 12... Display, 13... Operation unit, 14... Memory, 15... Call unit, 16... Wireless communication IF, 17... Mobile terminal CPU, 20... Communication terminal, 21... Display, 22... Operation unit, 23... Memory, 24... Call unit, 25... Wireless communication IF, 27... Communication terminal CPU, 30... Image data, 40... Server, 41... Destination information storage unit, 42... Call management unit, 43... SSID information storage unit, 48... Face detection unit, 49... Face storage unit (face image storage unit), 45... Image data generation unit, 46... Server communication IF, 47... Server CPU, N... Public communication network.

Claims

1. An intercom system having a mobile terminal carried by a visitor and having a function of communicating with an external device via a public communication network, a communication terminal operated by a resident and having a function of communicating with the mobile terminal via the public communication network, and a server for managing communication between the mobile terminal and the communication terminal, Image data for calling the communication terminal using the mobile terminal is posted at the entrance, The mobile terminal has a call function, a camera, and a function of reading the image data by imaging the image data with the camera, Further, the server has a call destination information storage unit that stores the association between the image data and a specific communication terminal, a face detection unit that detects a face from an imaged image of a visitor by the camera, and a face image storage unit that stores a face image transmitted from the mobile terminal. When the mobile terminal reads the image data, it accesses the server based on the information of the image data, obtains Web information for calling the communication terminal associated with the image data from the server, and while the communication terminal can be called from the Web information, In accordance with the transmission of the Web information, the server makes a request to transmit an imaged image of the visitor's face, and if the face can be recognized from the image transmitted from the mobile terminal in response to this request, the server stores the image and permits the call of the communication terminal by the mobile terminal using the Web information, while If the face cannot be recognized from the transmitted image, the use of the Web information is made unavailable and the communication terminal cannot be called, characterized in that it is an intercom system.

2. The server has an SSID information storage unit that associates a specific access point with each communication terminal and stores the SSID information thereof, The server transmits the Web information to the mobile terminal that has received the access, and at the same time, obtains the SSID information received by the mobile terminal from the mobile terminal, If there is no SSID associated with and stored in the communication terminal among the acquired information, the intercom system according to claim 1 is characterized by not permitting the calling of the communication terminal by the mobile terminal based on the Web information.

3. The Web information transmitted from the server to the mobile terminal includes password information that is valid only once. By using the password, it becomes possible to call the communication terminal from the mobile terminal. Once a communication path is formed between the mobile terminal and the communication terminal, the password then becomes invalid and calling is no longer possible. The intercom system according to claim 1 or 2 is characterized by this.

Images