JP7419728B2 - Communication devices and computer programs for communication devices - Google Patents

Description

This specification discloses a technology related to a communication device that can establish a wireless connection with an external device.

Patent Document 1 discloses a technique for establishing a wireless connection between a camera and an AP using a smartphone. In response to receiving an operation from the user, the camera displays a QR code (registered trademark) containing information for setting communication parameters, and starts monitoring reception of a search signal. By reading the QR code displayed on the camera, the smartphone acquires information for setting communication parameters, and sends a search signal to the camera. When the camera receives a search signal from the smartphone, the camera transmits a response to the search signal to the smartphone. When a response is received from the camera, the smartphone uses the acquired information to set communication parameters, and sends the set communication parameters to the camera. Additionally, the smartphone performs similar processing with the AP and transmits communication parameters to the AP. Thereby, the camera can establish a wireless connection with the AP using the received communication parameters.

JP2017-28454A JP 2018-6983 Publication JP2018-37978A

“Device Provisioning Protocol Technical Specification Version 1.1” Wi-Fi Alliance, 2018

This specification discloses a novel technique for establishing a wireless connection between a communication device and a second external device using a first external device.

A communication device disclosed in this specification includes a first wireless interface, a second wireless interface different from the first wireless interface, an output section different from the second wireless interface, and a first wireless interface. a specific signal receiving unit that receives a specific signal from an external device via the second wireless interface; and specific information obtained using a public key after the specific signal is received from the first external device. a first output control unit that causes the output unit to output the specific information, and the public key is acquired by the first external device by outputting the specific information; , an authentication request receiving unit that receives an authentication request using the public key from the first external device via the first wireless interface after the specific information is output; an authentication response transmitter that transmits an authentication response that is a response to the authentication request to the first external device via the first wireless interface when the authentication request is received from an external device; A connection information receiving unit that receives connection information from the first external device via the first wireless interface after a response is transmitted to the first external device, the connection information comprising: the connection information receiving section, which is information for establishing a wireless connection between the communication device and the second external device via the first wireless interface; and the connection information from the first external device. an establishing unit that establishes the wireless connection between the communication device and the second external device via the first wireless interface when the connection information is received. .

According to the above configuration, the communication device outputs the specific information obtained using the public key after receiving the specific signal from the first external device via the second wireless interface. As a result, the public key is obtained by the first external device. Thereafter, the communication device receives an authentication request using a public key from the first external device via a first wireless interface different from the second wireless interface, and sends an authentication response to the first external device. and receiving connection information from the first external device. Thereby, the communication device can establish a wireless connection with the second external device using the connection information.

Further, the communication device disclosed in this specification includes a first wireless interface, a second wireless interface different from the first wireless interface, and a communication device that receives the second wireless interface from a first external device. a specific signal receiving unit that receives a specific signal from the first external device; and a first state transition that shifts the state of the communication device from a disabled state to a enabled state after the specific signal is received from the first external device. The disabled state is a state in which an authentication response that is a response to an authentication request is not transmitted, and the enabled state is a state in which the authentication response is transmitted in response to receiving the authentication request from the first external device. the first state transition unit being in a state of transmitting an authentication response to the first external device; and the authentication receiving the authentication request from the first external device via the first wireless interface. a request receiving unit; when the authentication request is received from the first external device after the state of the communication device is shifted to the enabled state, the authentication response is sent via the first wireless interface; an authentication response transmitter that transmits an authentication response to the first external device; and after the authentication response is transmitted to the first external device, from the first external device via the first wireless interface, A connection information receiving unit that receives connection information, the connection information being information for establishing a wireless connection between the communication device and a second external device via the first wireless interface. , when the connection information receiving unit receives the connection information from the first external device, the connection information is used to connect the communication device and the second external device to the first external device. an establishing unit that establishes the wireless connection via the wireless interface.

According to the above configuration, the communication device transitions from the disabled state to the enabled state after receiving the specific signal from the first external device via the second wireless interface. With this, when the communication device receives an authentication request from the first external device via the first wireless interface different from the second wireless interface, the communication device can transmit an authentication response to the first external device. can. The communication device can then receive connection information from the first external device and use the connection information to establish a wireless connection with the second external device.

A computer program for realizing the above communication device and a computer-readable recording medium that stores the computer program are also new and useful. Also, the method performed by the communication device described above is novel and useful. Further, a communication system including the above communication device and other devices (for example, a first external device, a second external device) is also new and useful.

The configuration of the communication system is shown. An explanatory diagram for explaining an outline of an example is shown. A sequence diagram of Bootstrapping processing in case A is shown. A sequence diagram of authentication processing is shown. A sequence diagram of Configuration processing is shown. A sequence diagram of Network Access processing is shown. A sequence diagram of Bootstrapping processing in case B is shown. A sequence diagram of Bootstrapping processing in case C is shown. A sequence diagram of Bootstrapping processing in case D is shown.

(Configuration of communication system 2; Figure 1)
As shown in FIG. 1, the communication system 2 includes an AP (abbreviation for Access Point) 6, a terminal 10, and a printer 100. In this embodiment, a situation is assumed in which a user uses the terminal 10 to establish a wireless connection between the printer 100 and the AP 6 according to the Wi-Fi method (hereinafter referred to as "Wi-Fi connection"). are doing.

(Configuration of terminal 10)
The terminal 10 is a portable terminal device such as a mobile phone (for example, a smartphone), a PDA, or a tablet PC. Note that in a modification, the terminal 10 may be a stationary PC, a notebook PC, or the like. The terminal 10 includes a camera 15, a Wi-Fi interface 16, and a Bluetooth (registered trademark) interface 17. Hereinafter, the interface will be simply referred to as "I/F", and Bluetooth will be simply referred to as "BT". The camera 15 is a device for photographing an object, and in this embodiment, it is particularly used for photographing a QR code for the AP 6 and the printer 100. The terminal 10 also stores a connection application 40 (hereinafter simply referred to as "application 40"). The application 40 is a program for establishing a Wi-Fi connection between the printer 100 and the AP 6, and is installed on the terminal 10 from a server on the Internet provided by the vendor of the printer 100, for example.

The Wi-Fi I/F 16 is a wireless interface for performing Wi-Fi communication according to the Wi-Fi method. The Wi-Fi method is based on, for example, the IEEE (Institute of Electrical and Electronics Engineers, Inc.) 802.11 standard and its equivalent standards (e.g. 802.11a, 11b, 11g, 11n, 11ac, etc.) This is a wireless communication method for performing wireless communication according to the following. In particular, the Wi-Fi I/F 16 supports the DPP (abbreviation for Device Provisioning Protocol) method that is scheduled to be formulated by the Wi-Fi Alliance. The DPP method is described in "DRAFT Device Provisioning Protocol Technical Specification Version 0.2.11," which is a draft standard created by the Wi-Fi Alliance. This is a wireless communication method for easily establishing a Wi-Fi connection between APs (6).

The BT I/F 17 is a wireless interface for performing BT communication according to the BT method. The BT method is, for example, a wireless communication method based on the IEEE802.15.1 standard and standards corresponding thereto. More specifically, the BT I/F 17 supports BLE (abbreviation for Bluetooth Low Energy). BLE is a standard implemented in version 4.0 and later versions of the BT system.

The differences between the Wi-Fi method and the BT method will be described. The communication speed of Wi-Fi communication (for example, the maximum communication speed is 600 Mbps) is faster than the communication speed of BT communication (for example, the maximum communication speed is 24 Mbps). The frequency of a carrier wave in Wi-Fi communication is a 2.4 GHz band or a 5.0 GHz band. The frequency of carrier waves in BT communication is the 2.4 GHz band. That is, when the 5.0 GHz band is adopted as the frequency of the carrier wave in Wi-Fi communication, the frequency of the carrier wave in Wi-Fi communication is different from the frequency of the carrier wave in BT communication. Further, the maximum distance at which Wi-Fi communication can be performed (for example, approximately 100 m) is greater than the maximum distance at which BT communication can be performed (for example, approximately several tens of meters).

(Configuration of printer 100)
The printer 100 is a peripheral device (for example, a peripheral device of the terminal 10) that can perform a printing function. The printer 100 includes an operation section 112, a display section 114, a Wi-Fi I/F 116, a BTI/F 117, a print execution section 118, and a control section 130. Each part 112 to 130 is connected to a bus line (numerals omitted).

The operation unit 112 includes a plurality of keys. A user can input various instructions to the printer 100 by operating the operation unit 112. The display unit 114 is a display for displaying various information. The Wi-Fi I/F 116 is similar to the Wi-Fi I/F 16 of the terminal 10. That is, the Wi-Fi I/F 116 supports the DPP method. Furthermore, the Wi-Fi I/F 116 has a MAC address "abc". The BTI/F 117 is similar to the BTI/F 17 of the terminal 10. The printing execution unit 118 includes a printing mechanism such as an inkjet method or a laser method.

The control unit 130 includes a CPU 132 and a memory 134. CPU 132 executes various processes according to program 136 stored in memory 134. The memory 134 is composed of volatile memory, nonvolatile memory, and the like.

(Summary of this example; Figure 2)
Next, an overview of this embodiment will be explained with reference to FIG. 2. As mentioned above, the terminal 10 and the printer 100 support the DPP method, but the AP 6 also supports the DPP method. In this embodiment, each device 6, 10, 100 executes communication according to the DPP method, thereby establishing a Wi-Fi connection between the printer 100 and the AP 6. In the following, for ease of understanding, the operations executed by the CPU (for example, CPU 132, etc.) of each device will not be described with the CPU as the main body, but will be described with each device (for example, the printer 100) as the main body.

At T5, the terminal 10 performs DPP-based bootstrapping (hereinafter simply referred to as "BS") with the AP6. In response to the QR code pasted on the AP 6 being photographed by the terminal 10, the BS transmits information used in Authentication (hereinafter simply referred to as "Auth") in T10, which will be described later, from the AP 6. This is a process provided to the terminal 10.

At T10, the terminal 10 uses the information already acquired by the BS at T5 to perform DPP Auth with the AP6. The Auth is a process for each of the terminal 10 and the AP 6 to authenticate the communication partner.

At T15, the terminal 10 executes DPP configuration (hereinafter simply referred to as "Config") with the AP6. The Config is a process for transmitting information for establishing a Wi-Fi connection between the printer 100 and the AP 6 to the AP 6. Specifically, in the Config, the terminal 10 creates a first Configuration Object (hereinafter, the Configuration Object is simply referred to as "CO") for establishing a Wi-Fi connection between the printer 100 and the AP 6. ) and sends the first CO to the AP6. As a result, the first CO is stored in AP6.

Next, the terminal 10 executes a DPP type BS with the printer 100 at T20. The BS is a process in which the printer 100 provides the terminal 10 with information used in Auth at T25, which will be described later, in response to the terminal 10 photographing the QR code displayed on the printer 100.

At T25, the terminal 10 performs DPP Auth with the printer 100 using the information already acquired by the BS at T20. The Auth is a process by which each of the terminal 10 and the printer 100 authenticates the communication partner.

At T30, the terminal 10 executes DPP configuration with the printer 100. The Config is a process for transmitting information to the printer 100 for establishing a Wi-Fi connection between the printer 100 and the AP 6. In the Config, the terminal 10 generates a second CO for establishing a Wi-Fi connection between the printer 100 and the AP 6, and sends the second CO to the printer 100. As a result, the second CO is stored in the printer 100.

At T35, the printer 100 and the AP 6 execute DPP-based Network Access (hereinafter simply referred to as "NA") using the stored first and second COs. NA is a process for sharing a connection key for establishing a Wi-Fi connection between the printer 100 and the AP 6.

At T40, the printer 100 and the AP 6 execute 4-way-handshake communication. In at least a part of the 4-way-handshake communication, the printer 100 and the AP 6 communicate encrypted information using the connection key shared by the NA of T35. Then, if the decryption of the encrypted information is successful, a Wi-Fi connection is established between the printer 100 and the AP 6. As a result, the printer 100 can participate as a slave station in the wireless network formed by the AP 6, and as a result, can communicate with other devices participating in the wireless network via the AP 6. I can do it. In a modification, the printer 100 and the AP 6 may perform SAE (Simultaneous Authentication of Equals, commonly known as "Dragonfly") communication instead of 4-way-handshake communication.

At T45, the printer 100 causes the display unit 114 to display a completion screen indicating that the Wi-Fi connection has been established with the AP 6. When the process at T45 ends, the process in FIG. 2 ends.

In the DPP method, in order to establish a Wi-Fi connection between the printer 100 and the AP 6, the user enters information (for example, SSID (Service Set Identifier), password, etc.) on the wireless network in which the AP 6 operates as a master station. There is no need to input the information into the printer 100. Therefore, the user can easily establish a Wi-Fi connection between the printer 100 and the AP 6.

(Explanation of each process; Figures 3 to 9)
Next, details of each process executed at T20 to T35 in FIG. 2 will be explained with reference to FIGS. 3 to 9. Note that the processing from T5 to T15 is the same as the processing from T20 to T30, except that AP6 is used instead of the printer 100, so a detailed explanation thereof will be omitted. Further, FIG. 3 and FIGS. 7 to 9 show each case of BS executed between the terminal 10 and the printer 100. These cases are the processes performed in one embodiment.

(Bootstrapping (BS) of case A; Figure 3)
First, with reference to FIG. 3, the processing of case A of the BS at T20 in FIG. 2 will be described. In the initial state of FIG. 3, the memory 134 of the printer 100 stores the public key PPK1 and private key psk1 of the printer 100 in advance.

In response to receiving the power ON operation from the user at T100, the printer 100 displays the menu screen MS on the display unit 114 at T105. In other words, the screen MS is a default screen for the printer 100, and includes a print button for causing the printer 100 to execute printing, and a setting button for specifying various settings for the printer 100 (for example, print settings, etc.).

In response to the user selecting the settings button on the screen MS at T106, the printer 100 causes the display unit 114 to display the settings screen SS at T107. The screen SS includes a print settings button for changing the print settings of the printer 100, a QR code button for causing the printer 100 to display a QR code, and a mode transition button for changing the operation mode of the BTI/F 117. and, including.

In response to the user selecting the QR code button on the screen SS at T120, the printer 100 transitions from the disabled state to the enabled state at T122. In the impossible state, even if the Wi-Fi I/F 116 receives a DPP Authentication Request (hereinafter simply referred to as "AReq") (see T200 in FIG. In this case, it is in a state in which a message (simply written as "ARes") (see T210 described later) is not transmitted. That is, the impossible state is a state in which ARes, which is a response to AReq, is not transmitted. The enabled state is a state in which the Wi-Fi I/F 116 transmits ARes to the terminal 10 in response to receiving an AReq from the terminal 10. That is, the printer 100 enters a state in which Auth (see T25 in FIG. 2) can be executed by transitioning from the disabled state to the enabled state. Specifically, in this embodiment, the impossible state is a state in which the Wi-Fi I/F 116 does not supply the signal to the CPU 132 even if it receives a signal from the outside. The enabled state is a state in which, in response to receiving a signal from the outside, the Wi-Fi I/F 116 supplies the signal to the CPU 132 and transmits a response to the signal. Since the enabled state is a state in which the CPU 132 processes signals received from the outside, the processing load is higher than that in the disabled state. In a modified example, the impossible state may be a state in which the Wi-Fi I/F 116 is not energized, and the possible state may be a state in which the Wi-Fi I/F 116 is energized. In another modification, the impossible state is a state in which even if the Wi-Fi I/F 116 receives an AReq from the outside, it does not supply a notification indicating that the AReq has been received to the CPU 132, and the possible state is , the Wi-Fi I/F 116 may be in a state of supplying a notification indicating that the AReq has been received to the CPU 132 in response to receiving the AReq from the outside.

Next, at T124, the printer 100 displays the QR code on the display unit 114. The QR code is created by encoding the public key PPK1 stored in the memory 134 in advance, the channel list stored in the memory 134 in advance, and the MAC address "abc" of the Wi-Fi I/F 116. This is the resulting code image. The channel list is a list of values of multiple communication channels to be used in Auth (see T25 in FIG. 2). The QR code may be generated by the printer 100 when the process of T124 is executed, or may be stored in advance in the memory 134 from the time the printer 100 is shipped.

At T130, the terminal 10 starts the application 40 and also starts the camera 15 in response to receiving an operation to start the application 40 from the user. Each subsequent process executed by the terminal 10 is realized by the application 40. Next, at T132, the terminal 10 uses the camera 15 to photograph the QR code (see T124) displayed on the printer 100. Then, at T134, the terminal 10 decodes the photographed QR code and obtains the public key PPK1, the channel list, and the MAC address "abc".

At T136, the terminal 10 displays a terminal-side confirmation screen TCS that asks the user whether or not to execute a connection process to establish a Wi-Fi connection between the printer 100 and the AP 6. The screen TCS includes a YES button indicating to execute the connection process and a NO button indicating not to execute the connection process. At T140, the terminal 10 receives a selection of the YES button in the screen TCS from the user. When the process of T140 ends, the BS process of case A ends.

(Authentication (Auth); Figure 4)
Next, with reference to FIG. 4, the Auth process at T25 in FIG. 2 will be described. The terminal 10 generates the public key TPK1 and the private key tsk1 of the terminal 10 at T141 in response to the user selecting the YES button in the screen TCS at T140 in FIG. Next, at T142, the terminal 10 uses the generated private key tsk1 and the public key PPK1 of the printer 100 acquired at T134 in FIG. 3 according to ECDH (Elliptic curve Diffie-Hellman key exchange). , generates a shared key SK1. Then, at T144, the terminal 10 encrypts the random value RV1 using the generated shared key SK1 to generate encrypted data ED1.

At T200, the terminal 10 transmits the AReq to the printer 100 via the Wi-Fi I/F 16, using the MAC address "abc" acquired at T134 in FIG. 3 as the transmission destination. AReq is a signal requesting the printer 100 to perform authentication. Here, the terminal 10 repeatedly uses the plurality of communication channels in the channel list acquired at T134 to repeatedly transmit the AReq to the printer 100. The AReq includes the public key TPK1 of the terminal 10 generated at T141, the encrypted data ED1 generated at T144, and the capability of the terminal 10.

capability is information specified in advance for devices that support the DPP method, and has a value indicating that it can operate only as a Configurator of the DPP method, and a value indicating that it can operate only as an Enrollee of the DPP method. and a value indicating that it can operate as either a Configurator or an Enrollee. Note that the Configurator refers to a device that transmits the CO used in NA (T35 in FIG. 2) to the Enrollee in Config (T30 in FIG. 2). On the other hand, Enrollee means a device that receives CO used in NA from Configurator in Config. As described above, in this embodiment, the terminal 10 generates the first or second CO and transmits it to the AP 6 or the printer 100. Therefore, the capability of the terminal 10 includes a value indicating that it can operate only as a configurator.

The printer 100 receives an AReq from the terminal 10 via the Wi-Fi I/F 116 at T200. As described above, the AReq is sent with the MAC address "abc" of the printer 100 as the destination. Therefore, the printer 100 can appropriately receive the AReq from the terminal 10.

Further, when the printer 100 shifts to the enabled state at T124 in FIG. 3, it monitors whether an AReq using one communication channel among the plurality of communication channels in the channel list is received. As described above, the T200 AReq is transmitted sequentially using multiple communication channels in the channel list. Therefore, the printer 100 can appropriately receive the AReq from the terminal 10.

Next, the printer 100 executes the following process to authenticate the sender of the AReq (ie, the terminal 10). Specifically, first, in T202, the printer 100 uses the public key TPK1 of the terminal 10 in the AReq and the private key psk1 of the printer 100 stored in advance in the memory 134 according to the ECDH. Generate a shared key SK1. Here, the shared key SK1 generated by the terminal 10 at T142 and the shared key SK1 generated by the printer 100 at T204 are the same. Therefore, at T204, the printer 100 can appropriately decrypt the encrypted data ED1 in the AReq using the generated shared key SK1, and as a result, can obtain the random value RV1. If the encrypted data ED1 is successfully decrypted, the printer 100 determines that the source of the AReq is the device that photographed the QR code displayed on the printer 100, that is, the authentication is successful. , executes the processing from T206 onwards. On the other hand, if the encrypted data ED1 is not successfully decrypted, the printer 100 determines that the source of the AReq is not the device that photographed the QR code displayed on the printer 100, that is, the authentication has failed. Therefore, the process after T206 is not executed.

The printer 100 generates a new public key PPK2 and a new private key psk2 for the printer 100 at T206. Note that in a modified example, the public key PPK2 and the private key psk2 may be stored in the memory 134 in advance. Next, at T207, the printer 100 generates a shared key SK2 according to ECDH using the public key TPK1 of the terminal 10 in the AReq of T200 and the generated private key psk2 of the printer 100. Then, in T208, the printer 100 uses the generated shared key SK2 to encrypt the acquired random value RV1 and the new random value RV2 to generate encrypted data ED2.

At T210, the printer 100 transmits ARes to the terminal 10 via the Wi-Fi I/F 116. The ARes includes the public key PPK2 of the printer 100 generated at T206, the encrypted data ED2 generated at T208, and the capability of the printer 100. The capability includes a value indicating that it can operate only as an Enrollee.

At T210, in response to receiving the ARes from the printer 100 via the Wi-Fi I/F 16, the terminal 10 executes the following process to authenticate the source of the ARes (that is, the printer 100). . Specifically, first, in T212, the terminal 10 uses the private key tsk1 of the terminal 10 generated in T141 and the public key PPK2 of the printer 100 in the ARes to generate the shared key SK2 according to ECDH. generate. Here, the shared key SK2 generated by the printer 100 at T207 and the shared key SK2 generated by the terminal 10 at T212 are the same. Therefore, at T214, the terminal 10 can appropriately decrypt the encrypted data ED2 in the ARes using the generated shared key SK2, and as a result, can obtain the random values RV1 and RV2. . If the decryption of the encrypted data ED2 is successful, the terminal 10 determines that the source of the ARes is the device that displayed the photographed QR code, that is, the authentication is successful, and the Execute the process. On the other hand, if the decryption of the encrypted data ED2 is not successful, the terminal 10 determines that the source of the ARes is not the device that displayed the photographed QR code, that is, the terminal 10 determines that the authentication has failed. , the processing after T220 is not executed.

At T220, the terminal 10 transmits Confirm to the printer 100 via the Wi-Fi I/F 16. Confirm includes information indicating that the terminal 10 operates as a configurator and the printer 100 operates as an enrollee. As a result, at T222, the terminal 10 determines to operate as a configurator, and at T224, the printer 100 determines to operate as an enrollee. When the process at T224 ends, the process in FIG. 4 ends.

(Configuration (Config); Figure 5)
Next, with reference to FIG. 5, the Config processing at T30 in FIG. 2 will be described. At T300, the printer 100 transmits a DPP Configuration Request (hereinafter simply referred to as "CReq") to the terminal 10 via the Wi-Fi I/F 116. The CReq is a signal requesting transmission of CO (that is, information for establishing a Wi-Fi connection between the printer 100 and the AP 6).

The terminal 10 receives a CReq from the printer 100 via the Wi-Fi I/F 16 at T300. In this case, the terminal 10 acquires the group ID "Group1", the public key TPK2, and the private key tsk2 from the memory (not shown) of the terminal 10 at T301. As described above, the terminal 10 has already executed the Config at T15 in FIG. 2 with the AP 6, and at this time, generates the group ID "Group1", the public key TPK2, and the private key tsk2 and stores them in the memory. The group ID "Group1" is information that identifies a wireless network formed by establishing a Wi-Fi connection between the printer 100 and the AP 6. Note that in a modified example, a character string specified by the user may be used as the group ID. That is, at T301, the terminal 10 acquires each piece of information stored at T15 in FIG. Next, the terminal 10 generates a second CO (see T30 in FIG. 2) at T302. Specifically, the terminal 10 executes the following processes.

The terminal 10 generates a hash value HV by hashing the public key TPK2 of the terminal 10. Further, the terminal 10 generates a specific value by hashing the combination of the hash value HV, the group ID "Group1", and the public key PPK2 of the printer 100 in ARes at T210 in FIG. Then, the terminal 10 generates an electronic signature DS1 by encrypting the generated specific value using the private key tsk2 of the terminal 10 according to ECDSA (abbreviation for Elliptic Curve Digital Signature Algorithm). As a result, the terminal 10 creates a printer Signed-Connector (hereinafter, the Signed-Connector is simply (described as “SCont”) can be generated. Then, the terminal 10 generates a second CO including the printer SCont and the public key TPK2 of the terminal 10.

At T310, the terminal 10 transmits a DPP Configuration Response (hereinafter simply referred to as "CRes") including the second CO to the printer 100 via the Wi-Fi I/F 16.

The printer 100 receives CRes from the terminal 10 via the Wi-Fi I/F 116 at T310. In this case, the printer 100 stores the second CO in the CRes in the memory 134 at T312. When the process at T312 ends, the process in FIG. 5 ends.

(Network Access (NA); Figure 6)
Next, with reference to FIG. 6, the NA process at T35 in FIG. 2, which is executed between the printer 100 and the AP 6, will be described. As described above, similar to T20 to T30 in FIG. 2, the processes from T5 to T15 in FIG. 2 have already been executed between the terminal 10 and the AP 6. However, AP6 does not execute the processes from T105 to T124 in FIG. The AP6 stores in advance the public key APK1 and the private key ask1 of the AP6. A QR code obtained by encoding the public key APK1 of AP6, the channel list of AP6, and the MAC address of AP6 is pasted on the casing of AP6. When the terminal 10 photographs the QR code, processes similar to those after T134 are executed between the terminal 10 and the AP 6. As a result, the AP6 stores the public key APK2 and the private key ask2 of the AP6 (see T206 in FIG. 4), and further stores the first CO received from the terminal 10 (see T312 in FIG. 5). The first CO includes the AP SCont and the public key TPK2 of the terminal 10. The public key TPK2 is the same as the public key TPK2 included in the second CO. Furthermore, the AP SCont includes a hash value HV, a group ID "Group1", a public key APK2 of the AP6, and an electronic signature DS2. The hash value HV and the group ID "Group1" are respectively the same as the hash value HV and the group ID "Group1" included in the second CO. The electronic signature DS2 is information in which a specific value obtained by hashing the combination of the hash value HV, the group ID "Group1", and the public key APK2 is encrypted by the private key tsk2 of the terminal 10, and the second This value is different from the electronic signature DS1 included in the CO.

At T400, the printer 100 transmits a DPP Peer Discovery Request (hereinafter simply referred to as "DReq") including the printer SCont to the AP 6 via the Wi-Fi I/F 116. The DReq is a signal requesting the AP 6 to perform authentication and send the AP SCont.

At T400, in response to receiving the DReq from the printer 100, the AP 6 identifies the source of the DReq (i.e., the printer 100) and each piece of information in the DReq (i.e., the hash value HV, "Group 1", and the public key). PPK2) is executed. Specifically, in T402, the AP6 first sets the hash value HV and group ID "Group1" in the received printer SCont to hash values in the AP SCont included in the stored first CO. A first AP determination process regarding whether or not the value HV matches the group ID "Group1" is executed. In the case of FIG. 6, the AP 6 determines that they "match" in the first AP determination process, and therefore determines that the authentication of the source of the DReq (that is, the printer 100) has been successful. Note that the hash value HV in the received printer SCont and the hash value HV in the AP SCont included in the stored first CO match, which means that the printer SCont and the AP SCont are the same. , means that they were generated by the same device (ie, the terminal 10). Therefore, the AP 6 also determines that the authentication of the generation source (that is, the terminal 10) of the received printer SCont has been successful. Further, the AP 6 decrypts the electronic signature DS1 in the received printer SCont using the public key TPK2 of the terminal 10 included in the stored first CO. In the case of FIG. 6, the decryption of the electronic signature DS1 is successful, so the AP 6 uses the specific value obtained by decrypting the electronic signature DS1 and each information in the received printer SCont (i.e., the hash value HV , "Group1", and the value obtained by hashing the public key PPK2). In the case of FIG. 6, since the AP 6 determines that they "match" in the second AP determination process, it determines that the authentication of each piece of information in the DReq has been successful, and executes the processes from T404 onwards. The fact that the second CO is determined to be a "match" in the second AP determination process means that after the second CO is stored in the printer 100, each information in the received printer SCont (i.e. hash value HV, "Group1 ” and the public key PPK2) have not been tampered with by a third party. On the other hand, if it is determined that "does not match" in the first AP determination process, if decryption of the electronic signature DS1 fails, or if it is determined that "does not match" in the second AP determination process, The AP 6 determines that the authentication has failed and does not execute the process from T404 onwards.

Next, at T404, the AP 6 generates a connection key (that is, a shared key) CK using the acquired public key PPK2 of the printer 100 and the stored private key ask2 of the AP 6 according to the ECDH.

At T410, the AP 6 transmits a DPP Peer Discovery Response (hereinafter simply referred to as “DRes”) including the AP SCont to the printer 100.

At T410, in response to receiving the DRes from the AP 6 via the Wi-Fi I/F 116, the printer 100 identifies the source of the DRes (i.e., the AP 6) and each information in the DRes (i.e., the hash value HV, "Group1" and public key APK2) are authenticated. Specifically, in T412, the printer 100 first sets the hash value HV and group ID "Group1" in the received AP SCont to the printer SCont included in the stored second CO. A first PR determination process regarding whether or not the hash value HV matches the group ID "Group1" is executed. In the case of FIG. 6, the printer 100 determines that they "match" in the first PR determination process, and therefore determines that the authentication of the DRes source (namely, AP 6) has been successful. Note that the fact that the hash value HV in the received AP SCont matches the hash value HV in the printer SCont included in the stored second CO means that the printer SCont and the AP SCont are , means that they were generated by the same device (ie, the terminal 10). Therefore, the printer 100 also determines that the authentication of the generation source (that is, the terminal 10) of the received AP SCont has been successful. Further, the printer 100 decrypts the electronic signature DS2 in the received AP SCont using the public key TPK2 of the terminal 10 included in the stored second CO. In the case of FIG. 6, since the electronic signature DS2 is successfully decrypted, the printer 100 uses the specific value obtained by decrypting the electronic signature DS2 and each information (i.e., hash value) in the received AP SCont. HV, "Group1", and the value obtained by hashing the public key APK2). In the case of FIG. 6, the printer 100 determines that they "match" in the second PR determination process, so it determines that the authentication of each piece of information in the DRes has been successful, and executes the processes from T414 onwards. The second PR determination process determines that they "match" after the first CO is stored in the AP 6. This means that the public key APK2) has not been tampered with by a third party. On the other hand, if it is determined in the first PR determination process that they do not match, if decryption of the electronic signature DS2 fails, or if it is determined that they do not match in the second PR determination process, The printer 100 determines that the authentication has failed, and does not execute the process from T414 onwards.

At T414, the printer 100 generates a connection key CK according to the ECDH using the stored private key psk2 of the printer 100 and the public key APK2 of the AP6 in the received AP SCont. Here, the connection key CK generated by the AP 6 at T404 and the connection key CK generated by the printer 100 at T414 are the same. As a result, the connection key CK for establishing a Wi-Fi connection is shared between the printer 100 and the AP 6. When T414 ends, the process in FIG. 6 ends.

As described above, after the connection key CK is shared between the printer 100 and the AP 6, at T40 in FIG. 2, the printer 100 and the AP 6 execute 4-way-handshake communication using the connection key CK. As a result, a Wi-Fi connection is established between the printer 100 and the AP 6. Note that, as described above, the printer 100 receives the AReq of T200 in FIG. 4 from the terminal 10 using one of the plurality of communication channels included in the channel list of the printer 100. That is, the printer 100 receives the T200 AReq from the terminal 10 using a communication channel that can be used by both the printer 100 and the terminal 10. On the other hand, at T40 in FIG. 2, the printer 100 establishes a Wi-Fi connection with the AP 6 using a communication channel that can be used by both the printer 100 and the AP 6. Here, the communication channel that can be used by the terminal 10 and the communication channel that can be used by the AP 6 may be different. In this embodiment, a communication channel for the printer 100 to receive an AReq from the terminal 10 at T200 in FIG. 4, and a communication channel for the printer 100 to establish a Wi-Fi connection with the AP 6 at T40 in FIG. different. However, in a modified example, the former communication channel and the latter communication channel may be the same.

(Bootstrapping (BS) of case B; Figure 7)
Next, with reference to FIG. 7, the processing of case B of the BS at T20 in FIG. 2 will be described. Case B is a state before T20 to T40 in FIG. 2 are executed, that is, a state in which the memory 134 of the printer 100 has not yet stored the second CO.

T500 and T505 are similar to T100 and T105 in FIG. At T509, since the memory 134 does not store the second CO, the printer 100 supplies the BTI/F 117 with a transition instruction to change the operation mode of the BTI/F 117. Shift from normal mode to setting mode. Therefore, in a state where the memory 134 does not store the second CO, the operation mode of the BT I/F 117 is automatically shifted from the normal mode to the setting mode simply by the user turning on the power of the printer 100. The normal mode is a mode in which an Advertise signal (T512 to be described later) according to the BT method cannot be interpreted (that is, a mode in which the Advertise signal is ignored even if it is received). The setting mode is a mode in which the Advertise signal can be interpreted (that is, a mode in which information in the Advertise signal is supplied to the CPU 132 when the Advertise signal is received).

In response to receiving the activation operation of the application 40 from the user, the terminal 10 activates the application 40 and further activates the camera 15 at T510. In this case, the terminal 10 broadcasts the Advertise signal via the BTI/F 17 at T512. The Advertise signal includes a display instruction predetermined in the application 40. For example, the display instruction is a character string that can be interpreted by the printer 100.

At T512, the printer 100 obtains a display instruction from the BTI/F 117 in response to receiving the Advertise signal from the terminal 10 via the BTI/F 117. In this case, the printer 100 executes the processes from T514 onwards in accordance with the display instruction included in the Advertise signal. At T514, the printer 100 displays the printer-side confirmation screen PCS on the display unit 114. The screen PCS is a screen that asks the user whether or not to cause the printer 100 to display the QR code. and a NO button indicating not to execute the process. As a result, for example, if the user does not wish to establish a Wi-Fi connection (for example, if the application 40 is started by mistake), the QR code will be displayed by selecting the NO button in the screen PCS. It is possible to prevent this from happening.

Furthermore, when an Advertise signal including a display instruction is broadcast at T512, there is a possibility that the screen PCS will be displayed on a printer different from the printer 100. In this case, the user can suppress the QR code from being displayed on the different printer by selecting the NO button on the screen PCS displayed on the different printer.

In response to the user selecting the YES button on the screen PCS at T520, the printer 100 transitions from the disabled state to the enabled state at T522, and displays the QR code on the display unit 114 at T524. T532 to T540 are similar to T132 to T140 in FIG. When the process at T540 ends, the process in FIG. 7 ends. Then, the Wi-Fi connection between the printer 100 and the AP 6 is established by each device 6, 10, 100 executing the same process as in FIGS. 4 to 6.

Although not shown, in case A of FIG. 3, the printer 100 also shifts the operation mode of the BTI/F 117 from the normal mode to the setting mode in response to receiving the power ON operation from the user at T100. let However, in case A of FIG. 3, before the application 40 is started on the terminal 10, the processes from T106 to T120 are executed and the QR code is displayed. Therefore, the printer 100 does not execute the process at T514 in FIG.

(Bootstrapping (BS) of case C; Figure 8)
Next, with reference to FIG. 8, the processing of another case C of the BS will be described. Case C is a state after T20 to T40 in FIG. 2 have been executed, that is, a state in which the memory 134 of the printer 100 has already stored the second CO.

T600 and T605 are similar to T500 and T505 in FIG. In this case, since the memory 134 of the printer 100 stores the second CO, the printer 100 does not shift the operation mode of the BT I/F 117 from the normal mode to the setting mode. In a situation where the printer 100 stores the second CO, the printer 100 can establish a Wi-Fi connection with the AP 6 using the second CO. Therefore, the possibility that BS will be executed in printer 100 is low. Since the printer 100 does not shift the operation mode of the BTI/F 117 to the setting mode in such a situation, it is possible to suppress unnecessary display of the QR code.

For example, the user may desire to establish a Wi-Fi connection between the printer 100 and an AP different from the AP 6 while the printer 100 stores the second CO. In this case, the user can select the settings button in the screen MS in T606, and select the mode transition button in the screen SS (T607) that is displayed accordingly in T608. In this case, the printer 100 shifts the operation mode of the BTI/F 117 from the normal mode to the setting mode at T609. Thereby, when the printer 100 receives the Advertise signal from the terminal 10, it can execute the process from T514 onward in FIG. 7 and receive a new CO from the terminal 10.

Note that the printer 100 can also establish a Wi-Fi connection with the AP 6 according to a normal Wi-Fi method (that is, a method using an SSID and password) without using the DPP method. In this case, the memory 134 of the printer 100 stores wireless configuration information (ie, SSID and password) for establishing a Wi-Fi connection with the AP 6. Even if the power of the printer 100 is turned on in such a state, the printer 100 does not shift the operation mode of the BT I/F 117 from the normal mode to the setting mode, as in case C of FIG. This is because the printer 100 can establish a Wi-Fi connection with the AP 6 using the wireless setting information. This can prevent the process for establishing a Wi-Fi connection between the printer 100 and the AP 6 from being executed even though the printer 100 can establish a Wi-Fi connection with the AP 6. .

(Bootstrapping (BS) of case D; Figure 9)
Next, with reference to FIG. 9, processing of another case D of the BS will be described. Case D assumes a situation where the QR code displayed on the printer 100 is not photographed by the terminal 10.

T700 to T724 are similar to T500 to T524 in FIG. In this case, the AReq (see T200 in FIG. 4) is not transmitted from the terminal 10 to the printer 100 because the QR code displayed on the printer 100 is not photographed by the terminal 10. In this case, the printer 100 determines at T726 that no AReq is received within a predetermined time after transitioning to the enabled state at T722, and transitions from the enabled state to the disabled state at T728. Thereby, it is possible to prevent the printer 100 from remaining in the enabled state for a long time. That is, it is possible to prevent the Wi-Fi I/F 116 from continuing to supply signals received from the outside to the CPU 132, ie, the state where the CPU 132 processes signals received from the outside. Thereby, the processing load on the printer 100 can be reduced. Then, at T730, the printer 100 causes the display unit 114 to display an error screen indicating that the AReq was not received from the terminal 10. When the process at T730 ends, the process in FIG. 9 ends.

(Effects of this example)
In this embodiment, when the printer 100 receives an Advertise signal including a display instruction from the terminal 10 (T512 in FIG. 7, T612 in FIG. 8, T712 in FIG. 9), the printer 100 encodes the public key PPK1. Display the QR code (T522, T622, T722). As a result, the public key PPK1 is acquired by the terminal 10 (T534, T634). After that, the printer 100 receives the AReq using the public key TPK1 from the terminal 10 (T200 in FIG. 4), transmits ARes to the terminal 10 (T210), and receives the second CO from the terminal 10. (T310 in Figure 5). Thereby, the printer 100 can establish a Wi-Fi connection with the AP 6 using the second CO (T40 in FIG. 2).

Further, in this embodiment, when the printer 100 receives an Advertise signal including a display instruction from the terminal 10 (T512 in FIG. 7, T612 in FIG. 8, T712 in FIG. 9), the printer 100 shifts from the disabled state to the enabled state. (T524, T624, T724). Thereby, when the printer 100 receives an AReq from the terminal 10 (T200 in FIG. 4), it can transmit an ARes to the terminal 10 (T210). The printer 100 then receives the second CO from the terminal 10 (T310 in FIG. 5), and can establish a Wi-Fi connection with the AP 6 using the second CO (T40 in FIG. 2). ).

For example, a user who has knowledge of wireless communication or operation of the printer 100 selects the settings button on the screen MS at T106, as in case A of FIG. By selecting , the printer 100 can be caused to transition to the enabled state (T122) and display the QR code (T124). However, a user lacking the above-mentioned knowledge may not be able to appropriately perform the above-mentioned selection operation. According to this embodiment, as shown in case B of FIG. 7, when the printer 100 receives an Advertise signal including a display instruction from the terminal 10, even if T106 and T120 of FIG. 3 are not executed by the user. , transition to a possible state (T522) and display the QR code (T524). Therefore, a user with little knowledge of wireless communication can easily cause the printer 100 to transition to the enabled state and display the QR code by starting the application 40 on the terminal 10.

Further, for example, when an Advertise signal is received from the terminal 10, a wireless connection according to the BT method is established between the printer 10 and the terminal 10, and the public key PPK1 and the channel are transferred using the wireless connection. A comparative example is assumed in which the list and the MAC address "abc" are sent to the terminal 10. In this comparative example, the terminal 10 uses BT communication to obtain the public key PPK1, etc., without using a QR code. Here, the maximum distance at which BT communication can be performed is several tens of meters. Therefore, the user can operate the terminal 10 at a location away from the printer 100 to cause the terminal 10 to acquire the public key PPK1 of the printer 100. In contrast, in this embodiment, when the printer 100 receives the Advertise signal from the terminal 10, it displays the QR code without using the wireless connection according to the BT method (T524). Therefore, the user cannot cause the terminal 10 to acquire the public key PPK1 of the printer 100 unless the user approaches the printer 100. That is, in this embodiment, it is possible to prevent the terminal 10 from acquiring the public key PPK1 of the printer 100 at a location away from the printer 100.

(correspondence)
The printer 100, the terminal 10, and the AP 6 are examples of a "communication device," a "first external device," and a "second external device," respectively. The display unit 114, Wi-Fi I/F 116, and BTI/F 117 are examples of an "output unit," a "first wireless interface," and a "second wireless interface," respectively. The Advertise signal including the display instruction, the public key PPK1 of the printer 100, and the QR code are examples of the "specific signal,""publickey," and "specific information," respectively. AReq, ARes, and second CO are examples of "authentication request,""authenticationresponse," and "connection information," respectively. The Wi-Fi connection established at T40 in FIG. 2 is an example of a "wireless connection."

The selection operation of the QR code button at T120 in FIG. 3 is an example of a "predetermined operation." The screen PCS is an example of an "instruction screen." The selection operation of the mode transition button at T608 in FIG. 8 is an example of a "specific operation", and it is possible to accept a power ON operation from the user in a state where the second CO is not stored in the memory 134, and to Accepting the user's selection of the mode transition button while the second CO is stored in 134 is an example of the "predetermined condition." The normal mode and the setting mode are examples of a "first mode" and a "second mode", respectively. The channel list, the communication channel used at T200 in FIG. 4, and the communication channel used at T40 in FIG. This is an example. The elapse of a predetermined time at T726 in FIG. 9 is an example of a "specific condition."

Processing at T512 in FIG. 7 (or T612 in FIG. 8, T712 in FIG. 9), processing at T522 (or T622, T722), processing at T200 in FIG. 4, processing at T210, processing at T310 in FIG. 5, T35 and T40 These processes are executed by the "specific signal receiving section," "first output control section," "authentication request receiving section," "authentication response transmitting section," "connection information receiving section," and "establishing section," respectively. This is an example of processing.

Processing at T512 in FIG. 7 (or T612 in FIG. 8, T712 in FIG. 9), processing at T524 (or T624, T724), processing at T200 in FIG. 4, processing at T210, processing at T310 in FIG. 5, T35 and T40 These processes are executed by the "specific signal receiving section," "first state transition section," "authentication request receiving section," "authentication response transmitting section," "connection information receiving section," and "establishing section," respectively. This is an example of processing.

Although specific examples of the present invention have been described in detail above, these are merely illustrative and do not limit the scope of the claims. The techniques described in the claims include various modifications and changes to the specific examples illustrated above. Modifications of the above embodiment are listed below.

(Modification 1) For example, the QR code displayed on the printer 100 at T124 in FIG. 3 does not have to be one in which the channel list and the MAC address "abc" are encoded. That is, the QR code may be a code image obtained by encoding at least the public key PPK1. In this case, in response to the transition from the impossible state to the possible state at T122, the printer 100 receives an AReq in which one of all the wireless channels available to the printer 100 is used. monitor. Further, at T200 in FIG. 4, the terminal 10 sequentially transmits the AReq by broadcast, using all wireless channels available to the terminal 10. That is, the "specific information" may be information obtained using at least a public key.

(Modification 2) The process (for example, T142, T202 in FIG. 4) for generating a shared key (for example, SK1) is not limited to the process of the above embodiment according to ECDH, but can be other processes according to ECDH. It may be. Further, the process for generating the shared key is not limited to the process according to ECDH, but may be performed according to other methods (for example, DH (abbreviation for Diffie-Hellman key exchange), etc.). Further, in the above embodiment, the electronic signatures DS1 and DS2 were generated according to ECDSA, but other methods (for example, DSA (abbreviation for Digital Signature Algorithm), RAS (abbreviation for Rivest-Shamir-Adleman cryptosystem), etc.) may be generated according to

(Modification 3) When an Advertise signal including a display instruction is broadcast at T512 in FIG. 7, there is a possibility that the screen PCS will be displayed on a printer different from the printer 100. To deal with this situation, the printer 100 may broadcast a PReq instructing to stop displaying the screen PCS in response to receiving the AReq from the terminal 10 at T200 in FIG. . The PReq includes a stop instruction to stop displaying the screen PCS. Thereby, even if the screen PCS is displayed on a printer different from the printer 100, the display of the screen PCS can be stopped without receiving any operation from the user.

(Modification 4) For example, at T524 in FIG. 7, the printer 100 may have the print execution unit 118 print the QR code on the print medium instead of displaying the QR code on the display unit 114. . According to this modification, for example, in a situation where the printer 100 does not include the display unit 114 and it is impossible to display screens such as the screen MS at T105, the screen SS at T107, and the QR code at T122 in FIG. Also, it is possible to establish a Wi-Fi connection between the printer 100 and the AP 6 by executing communication according to the DPP method. In this modification, the print execution section 118 is an example of an "output section." In another modification, the printer 100 may transmit the public key PPK1, the channel list, and the MAC address "abc" to the terminal 10 via the Wi-Fi I/F 116. Specifically, when the printer 100 receives an Advertise signal including the MAC address of the terminal 10 and a transmission instruction, the printer 100 transmits the Advertise signal in accordance with the transmission instruction in the Advertise signal via the Wi-Fi I/F 116. The public key PPK1, etc. may be sent to the terminal 10 using the MAC address of . In this modification, the Wi-Fi I/F 116 is an example of an "output unit".

(Modification 5) In the modification, in response to receiving the Advertise signal from the terminal 10 at T512, the printer 100 calculates the received radio field strength of the Advertise signal, and determines whether the calculated received radio field strength is predetermined. If it is equal to or greater than the set threshold, the screen PCS may be displayed on the display unit 114 at T514. That is, the printer 100 may display the screen PCS on the display unit 114 on the condition that the distance between the printer 100 and the terminal 10 is less than or equal to a predetermined distance.

(Variation 6) The standard “Device Provisioning Protocol Technical Specification Version 1.1” created by the Wi-Fi Alliance states that shared codes, keys, phrases, and words are called “codes.” Therefore, in T122, the printer 100 generates an image containing the shared code, key, phrase, and word obtained by encoding the public key PPK1, the channel list, and the MAC address "abc" instead of the QR code. may be displayed on the display unit 114.

(Modification 7) At T35 in FIG. 2, NA processing may be executed between the terminal 10 and the printer 100, and a Wi-Fi connection may be established between the terminal 10 and the printer 100. That is, the "second external device" may be the same device as the "first external device."

(Modification 8) The screen SS displayed at T107 in FIG. 3 may not include the QR code button. In this case, the terminal 10 and the printer 100 execute the BS process of case B in FIG. 7 without executing the BS process of case A in FIG. Establish a connection. In this modification, the "second output control section" and the "third state transition section" can be omitted.

(Modification 9) In response to receiving the Advertise signal from the terminal 10 at T512 in FIG. 7, the printer 100 skips the processing at T514 and T520, and displays the QR code on the display unit 114 at T524. You can. In this modification, the "display control section" can be omitted.

(Modification 10) The Wi-Fi I/F 116 of the printer 100 may be configured to always operate in the setting mode. In this modification, the "mode transition unit" and the "storage control unit" can be omitted.

(Modification 11) The process of case D in FIG. 9 may not be executed. That is, the printer 100 does not need to shift from the enabled state to the disabled state when a predetermined period of time has elapsed since the printer 100 shifted to the enabled state. In this modification, the "second state transition section" can be omitted. Furthermore, in another modification, at T726 in FIG. 9, the printer 100 monitors for receiving an instruction from the user indicating that the transition to the impossible state is to occur, instead of monitoring that the predetermined time has elapsed. You can. In this modification, receiving an instruction from the user is an example of the "specific condition."

(Modification 12) In the above embodiment, a Wi-Fi connection is established between the printer 100 and the AP 6 using the terminal 10. Instead, for example, by using the terminal 10, a printer 100 (i.e., a device that operates as a master station) that operates as a G/O (abbreviation for Group Owner) of the WFD method and another device (i.e., a device that operates as a slave station) A Wi-Fi connection may be established between the operating device and the operating device. That is, the "second external device" does not have to be the "master station device."

(Modification 13) In the above embodiment, the terminal 10 transmits an Advertise signal including a display instruction to the printer 100 (T512 in FIG. 7). Alternatively, the printer 100 may periodically transmit an Advertise signal to the outside. Upon receiving the Advertise signal from the printer 100, the terminal 10 may display the device name of the printer 100 included in the Advertise signal. Here, when the terminal 10 receives an Advertise signal from each of a plurality of printers including the printer 100, the terminal 10 may display a plurality of device names corresponding to the plurality of printers. Then, when the user selects the device name of the printer 100 from among the plurality of device names, the terminal 10 may transmit a Scan Request including a display instruction to the printer 100 via the BTI/F 17. . In this modification, the QR code is displayed on the printer 100 of the plurality of printers, and a Wi-Fi connection with the printer 100 can be appropriately established. In this modification, Scan Request is an example of a "specific signal." In another modification, the Scan Request does not include a display instruction, and the printer 100 sends a response to the Scan Request to the terminal 10, thereby creating a pair between the printer 100 and the terminal 10 according to the BT method. A ring may be established. Then, the terminal 10 may transmit a signal including a display instruction to the printer 100 via the BTI/F 17 using the pairing. In this modification, the signal using pairing is an example of a "specific signal."

(Modification 14) The "communication device" does not need to be a printer, and may be other devices such as a scanner, a multi-function device, a mobile terminal, a PC, or a server.

(Modification 15) The processes at T522 in FIG. 7 and T722 in FIG. 9 may not be executed. In this modification, the printer 100 may always operate in the enabled state. In this modification, the "first state transition section" can be omitted.

(Modification 16) The processes at T524 in FIG. 7 and T724 in FIG. 9 may not be executed. In this modification, for example, after the state of the printer 100 becomes enabled in response to reception of an Advertise signal, the terminal 10 photographs the QR code pasted on the casing of the printer 100, and obtains the public key PPK1. etc. may be obtained. In this modification, the "first display control section" can be omitted.

(Modification 17) The "second wireless interface" does not need to be the BT/F117, and may be, for example, an I/F for performing communication according to the NFC (Near Field Communication) method, Zigbee (registered The Wi-Fi method may be an I/F for performing communication according to a method different from the Wi-Fi method, such as an I/F for performing communication according to the Wi-Fi method.

(Modification 18) In each of the above embodiments, each of the processes shown in FIGS. 2 to 9 is realized by software (that is, the program 136), but at least one of these processes is realized by hardware such as a logic circuit. May be realized.

Further, the technical elements described in this specification or the drawings exhibit technical usefulness singly or in various combinations, and are not limited to the combinations described in the claims as filed. Further, the techniques illustrated in this specification or the drawings simultaneously achieve multiple objectives, and achieving one of the objectives has technical utility in itself.

2: Communication system, 6: AP, 10: Terminal, 16, 116: Wi-Fi I/F, 17, 117: BT I/F, 40: Connection application, 100: Printer, 112: Operation unit, 114: Display unit, 118: Print execution unit, 130: Control unit, 132: CPU, 134: Memory, 136: Program

Claims (21)

A communication device,
a first wireless interface;
a second wireless interface different from the first wireless interface;
an output section different from the second wireless interface;
a specific signal receiving unit that receives a specific signal from a first external device via the second wireless interface;
A first output control unit that causes the output unit to output specific information obtained using a public key after the specific signal is received from the first external device, and the specific information is output. the first output control unit, wherein the public key is acquired by the first external device;
an authentication request receiving unit that receives an authentication request using the public key from the first external device via the first wireless interface after the specific information is output;
an authentication response transmitter that transmits an authentication response that is a response to the authentication request to the first external device via the first wireless interface when the authentication request is received from the first external device; and,
a connection information receiving unit that receives connection information from the first external device via the first wireless interface after the authentication response is transmitted to the first external device; the connection information receiving unit, which is information for establishing a wireless connection between the communication device and a second external device via the first wireless interface;
When the connection information is received from the first external device, the connection information is used to connect the communication device and the second external device to the wireless communication device via the first wireless interface. an establishment unit that establishes a connection;
A communication device comprising: The communication device further includes:
an operation section;
a second output control unit that causes the output unit to output the specific information when a predetermined operation via the operation unit is accepted;
The first output control unit outputs the specific information to the output unit even if the predetermined operation via the operation unit is not accepted after the specific signal is received from the first external device. The communication device according to claim 1. The communication device according to claim 1 or 2, wherein the specific information is a code image obtained by encoding the public key. The code image is a QR code (registered trademark),
The communication device according to claim 3, wherein the public key is acquired by the first external device in response to the QR code being photographed by the first external device. The output unit is a display unit for displaying an image,
The communication device according to any one of claims 1 to 4, wherein the first output control unit displays the specific information on the output unit that is the display unit. The communication device further includes:
an operation section;
a display control unit that causes the output unit, which is the display unit, to display an instruction screen for instructing that the specific information should be displayed when the specific signal is received from the first external device; Prepare,
The first output control unit displays the specific information on the output unit, which is the display unit, when an instruction to display the specific information is given via the operation unit on the instruction screen. The communication device according to claim 5. The communication device further includes:
a mode transition unit that transitions the operation mode of the second wireless interface from a first mode to a second mode when a predetermined condition is satisfied; is a mode in which the specific signal cannot be interpreted, and the second mode is a mode in which the second wireless interface can interpret the specific signal,
The first output control unit is configured to transmit the specific information to the specific information after the specific signal is received from the first external device in a situation where the operation mode of the second wireless interface is the second mode. output to the output section,
The communication device according to any one of claims 1 to 6, wherein the specific information is not output in a situation where the operation mode of the second wireless interface is the first mode. 8. The communication device according to claim 1, wherein the output unit is different from either the first wireless interface or the second wireless interface. The communication device further includes:
a first state transition unit that transitions the state of the communication device from a disabled state to a enabled state after the specific signal is received from the first external device, the disabled state being the authentication response is a state in which the authentication response is not transmitted, and the enabled state is a state in which the authentication response is transmitted to the first external device in response to receiving the authentication request from the first external device. Equipped with a state transition section of
The authentication response transmitter is configured to transmit the authentication response via the first wireless interface when the authentication request is received from the first external device after the state of the communication device has been shifted to the enabled state. The communication device according to any one of claims 1 to 8, wherein the communication device transmits an authentication response to the first external device. The specific information is information obtained using the public key and communication channel information indicating a first communication channel predetermined in the communication device,
By outputting the specific information, the communication channel information is acquired by the first external device,
The enable state monitors reception of the authentication request using the first communication channel from the first external device, and in response to receiving the authentication request from the first external device. , is in a state of transmitting the authentication response to the first external device,
The authentication response transmitter is configured to transmit the authentication response when the authentication request using the first communication channel is received from the first external device after the state of the communication device is shifted to the enabled state. The communication device according to claim 9, wherein the communication device transmits the authentication response to the first external device via a first wireless interface. A communication device,
a first wireless interface;
a second wireless interface different from the first wireless interface;
a specific signal receiving unit that receives a specific signal from a first external device via the second wireless interface;
a first state transition unit that transitions the state of the communication device from a disabled state to a enabled state after the specific signal is received from the first external device; A state in which an authentication response as a response is not sent, and the enabled state is a state in which the authentication response is sent to the first external device in response to receiving the authentication request from the first external device. the first state transition section;
an authentication request receiving unit that receives the authentication request from the first external device via the first wireless interface;
When the authentication request is received from the first external device after the state of the communication device is shifted to the enabled state, the authentication response is sent to the first external device via the first wireless interface. an authentication response transmitter for transmitting to an external device;
a connection information receiving unit that receives connection information from the first external device via the first wireless interface after the authentication response is transmitted to the first external device; the connection information receiving unit, which is information for establishing a wireless connection between the communication device and a second external device via the first wireless interface;
When the connection information is received from the first external device, the connection information is used to connect the communication device and the second external device to the wireless communication device via the first wireless interface. an establishment unit that establishes a connection;
A communication device comprising: The enabled state monitors that the communication device receives the authentication request using a predetermined first communication channel from the first external device, and receives the authentication request from the first external device. a state of transmitting the authentication response to the first external device in response to receiving the request;
The authentication response transmitter is configured to transmit the authentication response when the authentication request using the first communication channel is received from the first external device after the state of the communication device is shifted to the enabled state. The communication device according to claim 11 , wherein the communication device transmits the authentication response to the first external device via a first wireless interface. The establishment unit establishes the wireless connection between the communication device and the second external device via the first wireless interface using a second communication channel different from the first communication channel. The communication device according to claim 10 or 12, which establishes. The communication device further includes:
A second state transition unit that transitions the state of the communication device from the possible state to the impossible state when a specific condition is satisfied after the state of the communication device has been changed to the possible state. The communication device according to any one of Items 9 to 13. The communication device further includes:
an operation section;
a third state transition unit that transitions the state of the communication device from the disabled state to the enabled state when a predetermined operation via the operating unit is accepted;
The first state transition unit changes the state of the communication device to the disabled state even if the predetermined operation via the operation unit is not accepted after the specific signal is received from the first external device. The communication device according to any one of claims 9 to 14, wherein the communication device is configured to transition from a state to the enabled state. The communication device further includes:
a mode transition unit that transitions the operation mode of the second wireless interface from a first mode to a second mode when a predetermined condition is satisfied; is a mode in which the specific signal cannot be interpreted, and the second mode is a mode in which the second wireless interface can interpret the specific signal,
The first state transition unit changes the state of the communication device after the specific signal is received from the first external device in a situation where the operation mode of the second wireless interface is the second mode. transition from the impossible state to the possible state,
In a situation where the operation mode of the second wireless interface is the first mode, even if the specific signal is received from the first external device, the state of the communication device changes from the disabled state to the enabled state. 16. The communication device according to any one of claims 11 to 15, wherein the communication device is not migrated to. The communication device further includes:
memory and
a storage control unit that stores the connection information in the memory when the connection information is received from the first external device;
When the communication device is powered on in a situation where the connection information is not stored in the memory, the predetermined condition is satisfied;
17. The communication device according to claim 7, wherein the predetermined condition is not satisfied when the communication device is powered on in a situation where the connection information is stored in the memory. The communication device further includes:
Equipped with an operation section,
The communication device according to claim 17, wherein the predetermined condition is satisfied when a specific operation is accepted via the operation unit in a situation where the connection information is stored in the memory. The second external device is a device different from the first external device, and is a parent station device that should operate as a parent station of a wireless network,
The establishment unit establishes the wireless connection between the communication device and the second external device via the first wireless interface, and causes the communication device to participate in the wireless network as a slave station. A communication device according to any one of claims 1 to 18. A computer program for a communication device, the computer program comprising:
The communication device includes:
a first wireless interface;
a second wireless interface different from the first wireless interface;
an output section different from the second wireless interface;
computer and
Equipped with
The computer program causes the computer to run the following parts:
a specific signal receiving unit that receives a specific signal from a first external device via the second wireless interface;
A first output control unit that causes the output unit to output specific information obtained using a public key after the specific signal is received from the first external device, and the specific information is output. the first output control unit, wherein the public key is acquired by the first external device;
an authentication request receiving unit that receives an authentication request using the public key from the first external device via the first wireless interface after the specific information is output;
an authentication response transmitter that transmits an authentication response that is a response to the authentication request to the first external device via the first wireless interface when the authentication request is received from the first external device; and,
a connection information receiving unit that receives connection information from the first external device via the first wireless interface after the authentication response is transmitted to the first external device; the connection information receiving unit, which is information for establishing a wireless connection between the communication device and a second external device via the first wireless interface;
When the connection information is received from the first external device, the connection information is used to connect the communication device and the second external device to the wireless communication device via the first wireless interface. an establishment unit that establishes a connection;
A computer program that functions as A computer program for a communication device, the computer program comprising:
The communication device includes:
a first wireless interface;
a second wireless interface different from the first wireless interface;
computer and
Equipped with
The computer program causes the computer to run the following parts:
a specific signal receiving unit that receives a specific signal from a first external device via the second wireless interface;
a first state transition unit that transitions the state of the communication device from a disabled state to a enabled state after the specific signal is received from the first external device; A state in which an authentication response as a response is not sent, and the enabled state is a state in which the authentication response is sent to the first external device in response to receiving the authentication request from the first external device. the first state transition section;
an authentication request receiving unit that receives the authentication request from the first external device via the first wireless interface;
When the authentication request is received from the first external device after the state of the communication device is shifted to the enabled state, the authentication response is sent to the first external device via the first wireless interface. an authentication response transmitter for transmitting to an external device;
a connection information receiving unit that receives connection information from the first external device via the first wireless interface after the authentication response is transmitted to the first external device; the connection information receiving unit, which is information for establishing a wireless connection between the communication device and a second external device via the first wireless interface;
When the connection information is received from the first external device, the connection information is used to connect the communication device and the second external device to the wireless communication device via the first wireless interface. an establishment unit that establishes a connection;
A computer program that functions as

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