Computer program for a communication system and terminal and a communication device

Abstract

To provide a technique that can prevent larger size of a code image.SOLUTION: A terminal decodes a code image to obtain a string. The string does not include a public key of a communication device but includes identification information for identifying the communication device. The terminal obtains the public key of the communication device using the identification information and executes predetermined processing for performing a target communication with the communication device using the obtained public key. The target communication is a communication for establishing a wireless connection between a pair of devices according to a predetermined communication scheme.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] This specification discloses a technique for establishing a wireless connection between a pair of devices according to a predetermined communication method. [Background technology]

[0002] Non-Patent Document 1 describes the Device Provisioning Protocol method (hereinafter referred to as the "DPP method"), which is a wireless communication method established by the Wi-Fi Alliance. In one method of the DPP method, a public key of a first device is encoded and a code image obtained by reading the code image by a second device, thereby obtaining the public key by the second device. The second device can establish a Wi-Fi connection between the first device and an access point by communicating with the first device using the public key. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] “Wi-Fi Easy Connect Specification Version 2.0” Wi-Fi Alliance, 2020 Summary of the Invention [Problem to be solved by the invention]

[0004] When the public key has a large number of characters, the size of the code image may become large. In this specification, a technique is provided that can prevent the size of the code image from becoming large. [Means for solving the problem]

[0005] The communication system disclosed in this specification may include a communication device, a terminal, and a server. The terminal may include a camera, a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard, a display unit, a computer, a code image reading program not provided by a vendor of the communication device, and a terminal memory storing a browser program not provided by the vendor. The code image reading program may cause the computer to function as the following units, that is, a first character string acquisition unit that decodes a code image to acquire a character string when the code image is read by the camera, the character string not including a public key of the communication device and including a specific URI (abbreviation of Uniform Resource Identifier) ​​for downloading a vendor program provided by the vendor, the specific URI including identification information for identifying the communication device, and a supply unit that supplies the acquired character string to the browser program. The browser program may cause the computer to function as a first receiving unit that, when the character string is obtained from the code image reading program, uses the specific URI contained in the character string to receive specific web page data from the server for displaying a specific web page for downloading the vendor program, and a first display control unit that uses the specific web page data to display the specific web page on the display unit.After the vendor program is downloaded due to the specific web page being displayed on the display unit, the vendor program may cause the computer to function as the following units: a second string acquisition unit that decodes the code image and acquires the string when the code image is read again by the camera; a public key acquisition unit that acquires the public key of the communication device using the identification information in the specific URI contained in the acquired string; and a predetermined processing execution unit that executes a predetermined process using the acquired public key to execute target communication with the communication device via the wireless interface in accordance with the predetermined communication method, wherein the target communication is communication to establish a wireless connection between a pair of devices in accordance with the predetermined communication method.

[0006] According to the above configuration, the code image is an encoded character string that does not include a public key of the communication device. This can prevent the size of the code image from becoming large. In particular, the character string includes a specific URI, and the specific URI includes identification information for identifying the communication device. This allows the terminal to obtain the vendor program by using the specific URI, and to obtain the public key of the communication device by using the identification information.

[0007] This specification also discloses a computer program for a terminal. The terminal may include a camera, a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard, a display unit, and a computer. The computer program may cause the computer to function as the following units, that is, a string acquisition unit for decoding a code image and acquiring a string when the code image is read by the camera, the string not including a public key of a communication device and including identification information for identifying the communication device, a public key acquisition unit for acquiring the public key of the communication device by using the identification information included in the acquired string, and a predetermined processing execution unit for executing a predetermined process for executing a target communication according to the predetermined communication method with the communication device via the wireless interface by using the acquired public key, the target communication being a communication for establishing a wireless connection according to the predetermined communication method between a pair of devices.

[0008] This specification also discloses a communication device. The communication device may include a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard, a housing on which a sticker showing a code image obtained by encoding a character string is attached, the character string does not include a public key of the communication device, but includes identification information for identifying the communication device, the identification information being used by a terminal to obtain the public key, and a communication execution unit for executing target communication with the terminal via the wireless interface according to the predetermined communication method when the public key is obtained by the terminal, the target communication being communication for establishing a wireless connection between a pair of devices according to the predetermined communication method.

[0009] This specification also discloses the following communication device. The communication device may include a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard, an output control unit for causing an output unit to output a code image obtained by encoding a character string, the character string not including a public key of the communication device and including identification information for identifying the communication device, the identification information being used by a terminal to acquire the public key, and a communication execution unit for executing target communication with the terminal via the wireless interface according to the predetermined communication method when the public key is acquired by the terminal, the target communication being communication for establishing a wireless connection between a pair of devices according to the predetermined communication method.

[0010] According to the computer program for the terminal and each of the communication devices, the code image is an encoded character string that does not include a public key of the communication device. This can prevent the size of the code image from becoming large. In particular, the character string includes identification information that identifies the communication device. This allows the terminal to obtain the public key of the communication device by using the identification information.

[0011] The terminal itself and a method executed by the terminal are also novel and useful. A computer-readable recording medium storing a computer program for the terminal is also novel and useful. Also, a method executed by the communication device, a computer program for realizing the communication device, and a computer-readable recording medium storing the computer program are also novel and useful. [Brief description of the drawings]

[0012] [Figure 1] 1 shows a schematic configuration of a communication system. [Diagram 2] The control configuration of each device is shown. [Diagram 3] 1 shows a schematic sequence diagram of a process for establishing a Wi-Fi connection between a printer and an access point. [Figure 4] FIG. 1 shows a sequence diagram of bootstraping according to the first embodiment. [Diagram 5] The sequence diagram continues from Figure 4. [Figure 6] FIG. 13 is a sequence diagram of bootstraping according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] (First embodiment) (Configuration of communication system 2: Figure 1) 1, the communication system 2 includes an access point (hereinafter referred to as "AP") 6, a terminal 10, a printer 100, and servers 200 and 270. In this embodiment, a situation is assumed in which a user uses the terminal 10 to establish a wireless connection (hereinafter referred to as "Wi-Fi connection") between the printer 100 and the AP 6 in accordance with the Wi-Fi standard.

[0014] (Configuration of terminal 10: Figure 2) The terminal 10 is a portable terminal such as a mobile phone (e.g., a smartphone), a PDA, or a tablet PC. In a modified example, the terminal 10 may be a stationary terminal. As shown in FIG. 2, the terminal 10 includes an operation unit 12, a display unit 14, a Wi-Fi interface 16, a camera 20, and a control unit 30. Each unit 10 to 30 is connected to a bus line (reference numerals omitted). In the following, the interface is referred to as "I / F".

[0015] The operation unit 12 includes a plurality of buttons. A user can input various instructions to the terminal 10 by operating the operation unit 12. The display unit 14 is a display for displaying various information. The display unit 14 further functions as a so-called touch panel (i.e., an operation unit). The camera 20 is a device for photographing an object, and in this embodiment, is used for photographing a QR code (registered trademark) for the printer 100.

[0016] The Wi-Fi I / F 16 is a wireless interface for performing wireless communication according to the Wi-Fi standard. The Wi-Fi standard is a standard for performing wireless communication according to, for example, the IEEE (abbreviation of The Institute of Electrical and Electronics Engineers, Inc.) 802.11 standard and standards equivalent thereto (e.g., 802.11a, 11b, 11g, 11n, etc.). The terminal 10 can establish a Wi-Fi connection with the AP 6 via the Wi-Fi I / F 16 by using the SSID (abbreviation of Service Set Identifier) ​​and password of the wireless network formed by the AP 6.

[0017] The Wi-Fi I / F 16 also supports the DPP (Device Provisioning Protocol) method established by the Wi-Fi Alliance. The DPP method is described in the "Wi-Fi Easy Connect Specification Version 2.0" specification created by the Wi-Fi Alliance, and is a method for easily establishing a Wi-Fi connection between a pair of devices (e.g., the printer 100 and the AP 6) using the terminal 10. In the following, this specification will be referred to as the "DPP specification."

[0018] The control unit 30 includes a CPU 32 and a memory 34. The CPU 32 executes various processes in accordance with various programs 40 to 48 stored in the memory 34. The memory 34 is composed of a volatile memory, a non-volatile memory, etc. The memory 34 stores an OS program 40 and each application 42 to 48. Hereinafter, the OS program 40 will be referred to as "OS 40" and the application will be referred to as "app."

[0019] The OS 40 is a program for implementing basic operations of the terminal 10, and in this embodiment is Android (registered trademark). In a modified example, the OS 40 may be another type of OS (e.g., iOS). The OS 40 is pre-stored in the terminal 10 at the time of shipment of the terminal 10.

[0020] The reading application 42 is a program for reading a QR code. The browser application 44 is a program for displaying a web page. The DL application 46 is a program for accessing the server 270, which is a so-called application store, and downloading an application. The connection application 48 is a program for performing wireless communication according to the DPP method and establishing a Wi-Fi connection between the printer 100 and the AP 6. Each of the applications 42 to 48 is a standard application used together with the OS 40, and is pre-stored in the terminal 10 at the time of shipment of the terminal 10. In other words, each of the applications 42 to 48 is a program that is not provided by the vendor of the printer 100. In a modified example, the terminal 10 may have a so-called universal application instead of the connection application 48.

[0021] In the process described below, a printer application 50 is installed in the terminal 10. The printer application 50 is a program for causing the connection application 48 to execute wireless communication in accordance with the DPP method. The printer application 50 is also a program for causing the printer 100 to execute printing. The printer application 50 is a program provided by the vendor of the printer 100, and is installed in the terminal 10 after the shipment of the terminal 10.

[0022] (Configuration of printer 100: Figs. 1 and 2) The printer 100 is a peripheral device (for example, a peripheral device of the terminal 10) capable of executing a printing function. The printer 100 has a model name "AAA" and a serial number "xyz". As shown in FIG. 1, the printer 100 has a housing 100A. A sticker 100B showing a QR code is attached to the housing 100A. The QR code is information obtained by encoding a character string including a URI (short for Uniform Resource Identifier). The URI includes the domain of the server 200 and the serial number "xyz" of the printer 100.

[0023] 2, the printer 100 includes an operation unit 112, a Wi-Fi I / F 116, a print execution unit 118, and a control unit 130. Each unit 112 to 130 is connected to a bus line (reference numerals omitted). The printer 100 of this embodiment does not include a display unit capable of displaying a QR code. This means that the printer 100 does not include even one display unit, and that the printer 100 includes a very small display unit.

[0024] The operation unit 112 includes a plurality of buttons. A user can input various instructions to the printer 100 by operating the operation unit 112. The Wi-Fi I / F 116 supports the DPP method. The print 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. The CPU 132 executes various processes according to a program 136 stored in the memory 134. The memory 134 includes a volatile memory, a non-volatile memory, and the like.

[0025] (Server 200 configuration: Figure 2) The server 200 is a so-called web server, and is installed on the Internet 4 (see FIG. 1) by the vendor of the printer 100. The server 200 includes a communication I / F 216 and a control unit 230. The units 216 and 230 are connected to a bus line (reference numerals omitted). The communication I / F 216 is connected to the Internet 4. The control unit 230 includes a CPU 232 and a memory 234. The CPU 232 executes various processes according to a program 236 stored in the memory 234. The memory 234 is composed of a volatile memory, a non-volatile memory, etc.

[0026] Memory 234 further stores a model table 250. In model table 250, for each of a plurality of printer model names, the model name is associated with a message indicating a change operation for changing the state of a printer having that model name from DPPOFF state to DPPON state. The DPPOFF state and the DPPON state are states in which wireless communication according to the DPP method cannot be performed and can be performed, respectively.

[0027] (Outline of DPP: Figure 3) Next, an overview of DPP will be described with reference to Fig. 3. In the following, for ease of understanding, the operations executed by the CPU of each device (e.g. CPU 32) will be described with reference to each device (e.g. terminal 10, etc.) rather than to the CPU. Each communication below is executed using I / F 16, 116, 216 (see Fig. 2). For this reason, the description "via an I / F" will be omitted.

[0028] In this embodiment, the AP6 does not support the DPP method. The AP6 operates as a parent station of a wireless network using the SSID "sss" and the password "ttt". For example, the user of the terminal 10 operates the operation unit 12 to input the SSID "sss" and the password "ttt" to the terminal 10. In this case, the terminal 10 establishes a Wi-Fi connection with the AP6 using the OS 40. Thus, in the case of FIG. 3, it is assumed that a Wi-Fi connection is established between the terminal 10 and the AP6. When the user of the terminal 10 wants the printer 100 to execute printing, the user establishes a Wi-Fi connection between the printer 100 and the AP6, and executes communication between the terminal 10 and the printer 100 via the AP6. To achieve this, the following processes are executed.

[0029] At T25, the terminal 10 executes Bootstrapping (hereinafter referred to as "BS") described in the DPP standard with the printer 100. BS is a process in which the printer 100 provides the terminal 10 with the public key of the printer 100 used in Authentication (hereinafter referred to as "Auth") described in the DPP standard in response to the terminal 10 photographing a QR code shown on a sticker 100B (see FIG. 1) attached to the printer 100.

[0030] At T30, the terminal 10 executes Auth with the printer 100 using the public key acquired at the BS at T25. Auth is a process in which the terminal 10 and the printer 100 each authenticate the other party. Specifically, the terminal 10 transmits an Auth request using the public key to the printer 100, and receives an Auth response from the printer 100.

[0031] In T35, the terminal 10 executes Configuration (hereinafter referred to as "Config") described in the DPP standard with the printer 100. Config is a process for transmitting information for establishing a Wi-Fi connection between the printer 100 and the AP 6 to the printer 100. Specifically, the terminal 10 generates a Signed Connector (hereinafter referred to as "SC") and transmits the SC to the printer 100. The SC includes the SSID "sss" and password "ttt" of the AP 6.

[0032] In T40, the printer 100 establishes a Wi-Fi connection with the AP 6 using the SSID "sss" and password "ttt" included in the SC acquired in T35. Specifically, the printer 100 first broadcasts a probe request and receives a probe response from each of one or more APs, including the AP 6, that are present around the printer 100. In this case, the printer 100 recognizes that a probe response including the SSID "sss" included in the acquired SC (i.e., the SSID "sss" of the AP 6) is present among the one or more probe responses received from the one or more APs. Then, the printer 100 executes various communications with the AP 6, such as association and 4-way handshake, to establish a Wi-Fi connection with the AP 6. In the process of the various communications, the printer 100 transmits authentication information using the password "ttt" included in the acquired SC to the AP 6, and the AP 6 executes authentication of the password "ttt". If the authentication is successful, a Wi-Fi connection is established between the printer 100 and the AP 6.

[0033] As a result of the above processes, both the terminal 10 and the printer 100 participate as slave stations in the same wireless network formed by the AP 6. For this reason, the terminal 10 can transmit print data representing, for example, an image to be printed to the printer 100 via the AP 6. Then, the printer 100 can execute printing of the image represented by the print data.

[0034] In the DPP method, in order to establish a Wi-Fi connection between the printer 100 and the AP 6, the user does not need to input the SSID "sss" and password "ttt" of the AP 6 into the printer 100. Therefore, the user can easily establish a Wi-Fi connection between the printer 100 and the AP 6.

[0035] (BS details: Figures 4 and 5) The details of BS of T25 in Fig. 3 will be described with reference to Fig. 4 and Fig. 5. The QR code indicated by the sticker 100B of the printer 100 is an encoded character string 300. The character string 300 includes a URI "https: / / www.server.com / xyz". The URI includes the domain "www.server.com" of the server 200 and the serial number "xyz" of the printer 100. The character string 300 does not include the public key of the printer 100.

[0036] When the terminal 10 accepts an operation to start the reading application 42 from the user in T100, the terminal 10 executes the following processes of T102 to T106 in accordance with the reading application 42. When the terminal 10 accepts an operation to photograph the QR code indicated by the sticker 100B from the user in T102, the terminal 10 photographs the QR code with the camera 20. In T104, the terminal 10 decodes the QR code to obtain the character string 300. Then, in T106, the terminal 10 (i.e., the reading application 42) supplies the character string 300 to the browser application 44.

[0037] The terminal 10 executes the following processes from T110 to T116 in accordance with the browser application 44. In T110, the terminal 10 transmits a web page request including the URI indicated by the character string 300 as a destination to the server 200. As a result, the terminal 10 receives web page data representing the web page 400 from the server 200 in T112. Then, the terminal 10 displays the web page 400 in T114. The web page 400 includes a message indicating that the printer application 50 should be downloaded and a download button. When the terminal 10 (i.e., the browser application 44) accepts an operation of the download button in the web page 400 in T116, the terminal 10 supplies an application identifier for identifying the printer application 50 to the DL application 46 in T118.

[0038] The terminal 10 executes the following processes of T120 to T132 in accordance with the DL application 46. In T120, the terminal 10 transmits a web page request including the above-mentioned application identifier to the server 270. As a result, in T122, the terminal 10 receives web page data representing the web page 410 from the server 270. Then, in T124, the terminal 10 displays the web page 410. The web page 410 includes the name of the printer application 50 and a download button.

[0039] When the terminal 10 accepts an operation of the download button in the web page 410 in T126, the terminal 10 transmits a download request including the above-mentioned application identifier to the server 270 in T130. As a result, the terminal 10 receives (i.e., downloads) the printer application 50 from the server 270 in T132. As a result, the printer application 50 is installed in the terminal 10.

[0040] As shown in FIG. 5, when the terminal 10 accepts an operation to start the printer application 50 from the user in T150, the terminal 10 executes the following processes in accordance with the printer application 50: T152 to T160, T166 to T172, and T200 to T222.

[0041] When the terminal 10 accepts, in T152, an operation to photograph the QR code indicated by the sticker 100B from the user, the terminal 10 photographs the QR code with the camera 20. In T154, the terminal 10 decodes the QR code to obtain the character string 300. That is, the terminal 10 obtains the character string 300 again.

[0042] The terminal 10 generates the URI 330 at T156. Specifically, the terminal 10 first identifies the serial number "xyz" of the printer 100 from the character string 300. Then, the terminal 10 generates the URI 330 including the domain "www.server.com" of the server 200 that the printer application 50 has in advance, the character string "manual" that the printer application 50 has in advance, and the identified serial number "xyz". Here, the character string "manual" is a character string corresponding to a web page that indicates a change operation for changing the state of the printer 100 from the DPPOFF state to the DPPON state. In this way, since the terminal 10 generates the URI 330, the printer 100 does not need to have a QR code indicating the URI 330. It is possible to prevent the QR code of the printer 100 from becoming large. In addition, when the vendor of the printer 100 changes the URI in the server 200 (for example, when changing the character string "manual" to another character string), the vendor can update the printer application 50 to cause the terminal 6 to appropriately generate the changed URI.

[0043] Next, in T160, terminal 10 transmits a webpage request including the generated URI 330 as a destination to server 200. Here, terminal 10 transmits the webpage request and displays a webpage (described later) using printer application 50, not browser application 44. With this configuration, terminal 10 does not need to execute a process to start browser application 44. In other words, terminal 10 does not need to display a window different from the window displayed by printer application 50 (i.e., a window displayed by browser application 44). This prevents the processing load of terminal 10 from becoming high, and prevents the user from viewing multiple windows.

[0044] When the server 200 receives a web page request from the terminal 10 in T160, the server 200 first identifies the serial number "xyz" in the URI 330 included in the web page request in T162. The server 200 has a serial number table (not shown). The table stores, for each of a plurality of printers, the serial number of the printer and the model name of the printer in association with each other. Therefore, the server 200 can identify the model name "AAA" of the printer 100 from the serial number "xyz" by using the table in T162. In a modified example, the serial number "xyz" may include a character string indicating the model name "AAA". In this case, the server 200 can identify the model name "AAA" from the serial number "xyz" without using the serial number table.

[0045] Next, in T164, server 200 extracts a message "Please press the Wi-Fi button three times" corresponding to the model name "AAA" identified in T162 from model table 250 (see FIG. 2) in memory 234. Next, server 200 generates web page data representing a web page including the extracted message, a predetermined message, and a start button. The predetermined message indicates that the start button should be pressed after an operation according to the extracted message is performed. The start button is a button for causing terminal 10 to start Auth. Then, server 200 transmits the generated web page data to terminal 10 in T166.

[0046] When the terminal 10 receives the web page data from the server 200 in T166, in T170, the terminal 10 displays a web page 420 represented by the web page data on the display unit 14. The web page 420 includes the extracted message, the predetermined message, and a start button.

[0047] In response to the message in web page 420, the user presses the Wi-Fi button (not shown) included in operation unit 112 of printer 100 three times at T180. In this case, printer 100 transitions from DPPOFF state to DPPON state at T182. Specifically, printer 100 (i.e., CPU 132) supplies an instruction to Wi-Fi I / F 116 to transition from DPPOFF state to DPPON state. This puts printer 100 in a state in which it can execute communication according to the DPP method (for example, receiving an Auth request, sending an Auth response, etc.). In other words, web page 420 is an operation screen showing a change operation for changing the state of printer 100 from DPPOFF state to DPPON state.

[0048] As described above, according to this embodiment, the web page 420 includes a message for changing the state of the printer 100 having the model name "AAA" to the DPPON state. This allows the user to easily change the state of the printer 100 to the DPPON state. If the printer 100 is maintained in the DPPOFF state, the printer 100 cannot send an Auth response to the terminal 10. In this case, Auth fails and a Wi-Fi connection cannot be established between the printer 100 and the AP 6.

[0049] Next, the user executes an operation of selecting a start button in the web page 420 in T190. In this case, the terminal 10 generates the URI 340 in T200. Specifically, the terminal 10 generates the URI 340 including the domain "www.server.com" of the server 200 that the printer application 50 has in advance, the character string "key" that the printer application 50 has in advance, and the serial number "xyz" of the printer 100. Here, the character string "key" is a character string requesting the generation of the public key of the printer 100. In this way, since the terminal 10 generates the URI 340, the printer 100 does not need to have a QR code including the URI 340. It is possible to prevent the QR code of the printer 100 from becoming large. In addition, when the vendor of the printer 100 changes the URI in the server 200 (for example, when changing the character string "key" to another character string), the vendor can update the printer application 50 to cause the terminal 6 to appropriately generate the changed URI. The terminal 10 then sends a public key request to the server 200 at T210, the request including the generated URI 340 as destination.

[0050] When server 200 receives a public key request from terminal 10 in T210, server 200 generates public key 350 in T212. Specifically, server 200 first identifies serial number "xyz" in URI 340 included in the public key request. Next, server 200 generates public key 350 by performing a predetermined calculation on the identified serial number "xyz". Then, server 200 transmits public key 350 to terminal 10 in T214.

[0051] At T214, the terminal 10 receives the public key 350 from the server 200. In this manner, the terminal 10 (i.e., the printer application 50) does not generate the public key 350 by itself, but rather has the server 200 generate the public key 350. For this reason, the printer application 50 does not need to include a program for generating the public key 350.

[0052] Next, the terminal 10 generates BS information including the public key 350 in T220. The BS information is described in accordance with the Bootstrapping Information Format described in the DPP standard. More specifically, the BS information includes an identifier "K" according to the ABNF (abbreviation of Augmented Backus Naur Form) rules and a character string of the public key 350 associated with the identifier "K". The identifier "K" is an identifier indicating that the character string associated with the identifier "K" is the public key 350 of the printer 100. The terminal 10 (i.e., the printer application 50) supplies the generated BS information to the connection application 48 in T222.

[0053] Terminal 10 executes the following process of T230 in accordance with connection application 48. That is, terminal 10 identifies public key 350 from the BS information in T230. Since the BS information is described in accordance with the Bootstrapping Information Format described in the DPP standard, connection application 48 can appropriately identify the character string associated with identifier "K" as public key 350.

[0054] 3. That is, the terminal 10 transmits an Auth request to the printer 100 using the public key 350 identified in T230. In other words, the terminal 10 does not transmit an Auth request to the printer 100 until the start button in the web page 420 is operated. This makes it possible to prevent an Auth request from being transmitted from the terminal 10 to the printer 100 when the printer 100 is in the DPPOFF state.

[0055] When the printer 100 receives an Auth request from the terminal 10, it performs the same calculation as the calculation performed by the server 200 in T212 on the printer 100's own serial number "xyz" to generate a public key 350. This causes the public key 350 to be shared between the terminal 10 and the printer 100. The printer 100 then uses the public key 350 to authenticate the Auth request received from the terminal 10, and if the authentication is successful, sends an Auth response to the terminal 10.

[0056] 3, when the terminal 10 (i.e., the connection application 48) sends an Auth request to the printer 100, it receives an Auth response from the printer 100 (see T30 in FIG. 3), and then sends an SC to the printer 100 (see T35). This enables the terminal 10 to establish a Wi-Fi connection between the printer 100 and the AP 6 (see T40).

[0057] (Effects of this embodiment) According to the above configuration, the QR code shown by the sticker 100B is an encoded version of the character string 300 that does not include the public key 350 of the printer 100. This makes it possible to prevent the size of the QR code from becoming large. Usually, the number of characters in a URI is smaller than the number of characters in a public key. Therefore, a QR code showing a URI such as that in this embodiment is smaller than a QR code showing a public key. In particular, the character string 300 includes a URI, and the URI includes the serial number "xyz" of the printer 100. Therefore, the terminal 10 can use the URI to obtain the printer app 50 (T110 to T132 in FIG. 4) and can also use the serial number "xyz" to obtain the public key 350 of the printer 100 (T200 to T230 in FIG. 5).

[0058] (Correspondence) The printer 100, the server 200, and the server 270 are examples of a "communication device", a "server", and a "different server", respectively. The printer 100 and the AP 6 are examples of a "pair of devices". The printer application 50 is an example of a "vendor program" and a "computer program". The URI included in the character string 300 is an example of a "specific URI". The URI 330 and the URI 340 are examples of a "first URI" and a "second URI", respectively. The web page data of T112 and the web page 400 in FIG. 4 are examples of a "specific web page data" and a "specific web page", respectively. The web page data of T166 and the web page 420 in FIG. 5 are examples of a "first web page data" and a "first web page", respectively. The web page data of T122 and the web page 410 in FIG. 4 are examples of a "second web page data" and a "second web page", respectively. The operation of T116 and the operation of T126 in FIG. 4 are examples of a "first operation" and a "second operation", respectively. The DPPOFF state and the DPPON state are examples of an "impossible state" and an "available state", respectively. A message in web page 420 is an example of a "specific message". The serial number "xyz" is an example of "identification information". The processes of T156, T160, T166, and T170 in FIG. 5 are examples of "display processing". The processes of T220 and T222 are examples of "predetermined processing". The processes of T30 and T35 in FIG. 3 are examples of "target communication". The Auth request and Auth response are examples of an "authentication request" and an "authentication response", respectively. SC is an example of "connection information".

[0059] The correspondence of the "terminals" is as follows. The process of T104 and the process of T106 in FIG. 4 are examples of the process executed by the "first character string acquisition unit" and the "supply unit", respectively. The process of T112 and the process of T114 are examples of the process executed by the "first reception unit" and the "first display control unit", respectively. The process of T122, the process of T124, and the process of T132 are examples of the process executed by the "second reception unit", the "second display control unit", and the "download unit", respectively. The process of T154 in FIG. 5 is an example of the process executed by the "second character string acquisition unit" and the "character string acquisition unit". The process of T156 is an example of the process executed by the "first generation unit". T160, T166, and T170 are examples of the process executed by the "display process execution unit". The process of T200 is an example of the process executed by the "second generation unit". The processes of T210 and T214 are examples of the process executed by the "public key acquisition unit". The processes of T220 and T222 are an example of a process executed by a "predetermined process execution unit."

[0060] The correspondence of the "server" is as follows. The processes of T164 and T166 in FIG. 5 are examples of processes executed by the "extraction unit" and the "web page transmission unit", respectively. The correspondence of the "communication device" is as follows. The processes of T30 and T35 in FIG. 3 are examples of processes executed by the "communication execution unit".

[0061] (Second embodiment: Figure 6) Next, a second embodiment will be described. Explanation of the same points as in the first embodiment will be omitted. In this embodiment, the sticker 100B is not attached to the housing 100A of the printer 100. The printer 100 includes a display unit 114 (see FIGS. 1 and 2) that can display a QR code. The server 200 does not include a model table 250 (see FIG. 2).

[0062] In this embodiment, the BS in Fig. 6 is executed instead of the BS in Fig. 4 and Fig. 5. The user executes a DPP startup operation on the printer 100 in T300. This operation may be, for example, an operation of selecting a DPP button in the operation unit 112, or an operation of selecting a DPP button in a setting screen displayed on the display unit 114. When the printer 100 accepts this operation, it transitions from the DPPOFF state to the DPPON state in T302.

[0063] Next, in T304, the printer 100 generates a QR code and displays the QR code on the display unit 114. The QR code is an encoded version of the character string 300 (see FIG. 4) that is the same as in the first embodiment.

[0064] Thereafter, the same processes as T100 to T132 in Fig. 4 are executed. That is, the terminal 10 reads the QR code displayed on the printer 100 in T102. T310 to T314 are the same as T150 to T154 in Fig. 5. The terminal 10 does not execute T156 to T190 in Fig. 5. This is because the state of the printer 100 has already transitioned to the DPPON state in T302. T320 to T450 are the same as T200 to T230 in Fig. 5.

[0065] (Effects of this embodiment) In this embodiment, the QR code displayed by the printer 100 is also an encoded version of the character string 300 that does not include the public key 350 of the printer 100. This makes it possible to prevent the size of the QR code from becoming large. Therefore, the printer 100 can properly display the QR code even if the display unit 114 is not so large. In this embodiment, the process of T304 is an example of a process executed by the "output control unit".

[0066] Although specific examples of the technology disclosed in this specification have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. Modifications are listed below.

[0067] (Modification 1) In the case of FIG. 3, the terminal 10 establishes a Wi-Fi connection with the AP 6 by using the SSID "sss" and password "ttt" of the AP 6. Alternatively, the terminal 10 may establish a Wi-Fi connection with the AP 6 by performing wireless communication of the DPP method. That is, the AP 6 supports the DPP method and has a QR code indicating the public key of the AP 6 (for example, a sticker is attached to the housing of the AP 6). The terminal 10 acquires the public key of the AP 6 by photographing the QR code (that is, executes BS). Then, the terminal 10 executes Auth and Config with the AP 6. However, the terminal 10 generates an SC for AP in Config and transmits the SC for AP to the AP 6. Then, the terminal 10 and the AP 6 share a connection key by executing Network Access (hereinafter referred to as "NA") by using the SC for AP, and establish a Wi-Fi connection by using the connection key. Then, the terminal 10 executes BS, Auth, and Config (T25 to T35) with the printer 100. However, the terminal 10 generates a printer SC in Config that does not include the SSID and password of the AP 6, and transmits the printer SC to the printer 100. In this case, the printer 100 and the AP 6 share a connection key by executing NA using the printer SC and the AP SC, and establish a Wi-Fi connection using the connection key. In this modification, the printer SC is an example of "connection information."

[0068] (Variation 2) A Wi-Fi connection may be established between the terminal 10 and the printer 100, without establishing a Wi-Fi connection between the terminal 10 and the AP 6. In this case, the terminal 10 executes the processes of T25 to T35 in FIG. 3, and transmits the SC for the printer to the printer 100 at T35. The terminal 10 and the printer 100 then share a connection key by executing NA using the SC for the printer, and establish a Wi-Fi connection using the connection key. In this variation, the SC for the printer is an example of "connection information." Also, the terminal 10 and the printer 100 are an example of a "pair of devices."

[0069] (Variation 3) A Wi-Fi connection may not be established between the terminal 10 and the AP 6. Instead, a Wi-Fi connection may be established between the printer 100 and the AP 6. In this case, the terminal 10 executes each process from T25 to T35 in FIG. 3, and receives a terminal SC from the printer 100 at T35. Then, the terminal 10 and the AP 6 share a connection key by executing NA using the terminal SC, and establish a Wi-Fi connection using the connection key. In this variation, the terminal 10 and the AP 6 are an example of a "pair of devices." Also, as in this variation, the "target communication" may include receiving connection information from a communication device.

[0070] (Variation 4) The "identification information" is not limited to the serial number "xyz" and may be the model name of the printer 100, a MAC address, or the like.

[0071] (Variation 5) The terminal 10 does not need to have the connection application 48. In this case, the printer application 50 does not execute T220 and T222 in Fig. 5. Then, the printer application 50 executes the communications T30 and T35 in Fig. 3 using the public key 350. In this variation, executing the communications T30 and T35 using the public key 350 is an example of a "predetermined process."

[0072] (Variation 6) The web page data of T112 and T122 in Fig. 4 and T166 in Fig. 5 do not have to be data representing the web page itself, and may be data including character strings, images, etc. that constitute the web page. In this case, the terminal 10 generates the web page by using the web page data.

[0073] (Variation 7) The printer application 50 may supply the URI 330 generated in T156 of Fig. 5 to the browser application 44. In this case, the browser application 44 can execute the processes of T160, T166, and T170. In this variation, the process of supplying the URI 330 to the browser application 44 is an example of a "display process".

[0074] (Modification 8) The processes of T156 to T170 in Fig. 5 do not have to be executed. In this modification, the "display process execution unit", the "extraction unit", the "web page transmission unit", and the "first generation unit" can be omitted.

[0075] (Modification 9) T100 to T132 in Fig. 4 do not have to be executed. In this modification, the character string 300 does not have to include a URI. In other words, the character string 300 may include only the serial number "xyz" of the printer 100. In this case, the size of the QR code can be made smaller.

[0076] (Modification 10) The character string 300 may include all of the URI used in T110 of FIG. 4, the URI 330 used in T160 of FIG. 5, and the URI 340 used in T210. In this case, the terminal 10 can transmit a web page request including the URI 330 to the server 200 in T160 without executing T156. Also, the terminal 10 can transmit a web page request including the URI 340 to the server 200 in T210 without executing T200. In this modification, the "first generation unit" and the "second generation unit" can be omitted. Also, in the second embodiment (i.e., FIG. 6), the user may be able to select whether to display a QR code including only the URI used in T110 of FIG. 4 or to display a QR code including only the URI 340 used in T210 of FIG. 5 on the printer 100. In this case, the terminal 10 may read the former QR code at T102 in FIG. 4, and may read the latter QR code at T312 in FIG.

[0077] (Modification 11) The terminal 10 may generate the public key 350 by using the serial number "xyz" instead of the processes of T200 to T214 in Fig. 5. Generally speaking, the "public key acquisition unit" may acquire the public key without receiving the public key from the server.

[0078] (Variation 12) The terminal 10 (i.e., the browser application 44) may transmit a download request to the server 200 instead of a web page request in T110 of Fig. 4, and download the printer application 50 from the server 200. In this variation, T112 to T132 are not executed, and the "second receiving unit", "second display control unit", and "download unit" can be omitted.

[0079] (Modification 13) The server providing the web page data of T112 in Fig. 4, the server providing the web page data of T166 in Fig. 5, and the server providing the public key 350 of T214 may be different. Generally speaking, the "server" may be composed of one server 200 as in the above embodiment, or may be composed of multiple servers as in this modification.

[0080] (Modification 14) The terminal 10 and the printer 100 may not support the DPP method, and may support other methods for establishing a Wi-Fi connection using a public key, an authentication request, and an authentication response. Generally speaking, the "predetermined communication method" is not limited to the DPP method.

[0081] (Variation 15) The "communication device" does not have to be the printer 100, but may be other devices such as a scanner, a multi-function device, a mobile terminal, a PC, or a server.

[0082] (Modification 16) In the above embodiment, the processes in FIGS. 3 to 6 are implemented by software, but at least one of these processes may be implemented by hardware such as a logic circuit.

[0083] The technical elements described in this specification or drawings have technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technologies illustrated in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. The items described in the claims at the time of filing are listed below. (Item 1) 1. A communication system comprising: A communication device; A terminal, A server, The terminal includes: Camera and a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; A display unit; A computer, a terminal memory for storing a code image reading program not provided by a vendor of the communication device and a browser program not provided by the vendor; The code image reading program controls the computer to operate as follows: a first character string acquisition unit that, when a code image is read by the camera, decodes the code image to acquire a character string, the character string not including a public key of the communication device and including a specific URI (short for Uniform Resource Identifier) ​​for downloading a vendor program provided by the vendor, the specific URI including identification information for identifying the communication device; a supply unit that supplies the acquired character string to the browser program; The browser program causes the computer to a first receiving unit that, when the character string is acquired from the code image reading program, receives, from the server, specific web page data for displaying a specific web page for downloading the vendor program, by using the specific URI included in the character string; a first display control unit that uses the specific web page data to display the specific web page on the display unit; After the vendor program is downloaded due to the specific web page being displayed on the display unit, the vendor program controls the computer to include the following units: a second character string acquisition unit that decodes the code image and acquires the character string when the code image is read again by the camera; a public key acquisition unit that acquires the public key of the communication device by using the identification information in the specific URI included in the acquired character string; a predetermined processing execution unit that executes a predetermined process for executing target communication with the communication device according to the predetermined communication method via the wireless interface by using the acquired public key, the target communication being communication for establishing a wireless connection between a pair of devices according to the predetermined communication method; Communication systems. (Item 2) The vendor program further configures the computer to include the following units: a display processing execution unit that executes a display process using a first URI different from the specific URI, the display process being a process of receiving first web page data for displaying a first web page from the server and displaying the first web page on the display unit, the first web page indicating a change operation for changing a state of the communication device from an impossible state in which wireless communication according to the specified communication method cannot be performed to a possible state in which wireless communication according to the specified communication method can be performed; The communication system described in item 1, wherein the target communication is performed with the communication device after the state of the communication device is changed from the impossible state to the possible state due to the change operation indicated by the first web page being performed on the communication device. (Item 3) the first URI includes the identification information in the specific URI included in the acquired character string; the display process includes a process of transmitting a web page request to the server with the first URI as a destination; The server, a server memory for storing, for each of a plurality of types of devices, a message indicating a change operation for changing the state of the device from the disabled state to the enabled state; an extractor that extracts, when the web page request is received from the terminal, from the server memory, a specific message corresponding to the communication device identified by the identification information included in the first URI; a web page sending unit that sends the first web page data including the extracted specific message to the terminal; 3. The communication system according to item 2, comprising: (Item 4) The communication system according to any one of items 1 to 3, wherein the public key acquisition unit acquires the public key by sending the identification information to the server with a second URI different from the specific URI as a destination, and receiving from the server the public key generated by the server from the identification information. (Item 5) The terminal memory further stores a download program not provided by a vendor of the communication device; The download program controls the computer to operate as follows: a second receiving unit that receives, when a first operation for downloading the vendor program is executed on the specific web page, second web page data for displaying a second web page for downloading the vendor program from a server different from the server; a second display control unit that uses the second web page data to display the second web page on the display unit; a download unit that downloads the vendor program when a second operation for downloading the vendor program is executed on the second web page; 5. The communication system according to any one of claims 1 to 4, (Item 6) The terminal memory further stores a connectivity program not provided by a vendor of the communication device; 6. The communication system according to any one of claims 1 to 5, wherein the predetermined process includes supplying the public key to the connection program so as to cause the connection program to execute the target communication with the communication device. (Item 7) A computer program for a terminal, comprising: The terminal includes: Camera and a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; A display unit; A computer, The computer program causes the computer to operate in the following manner: a character string acquisition unit that, when a code image is read by the camera, decodes the code image to acquire a character string, the character string not including a public key of a communication device and including identification information for identifying the communication device; a public key acquisition unit that acquires the public key of the communication device by using the identification information included in the acquired character string; a predetermined processing execution unit that executes a predetermined process for executing a target communication with the communication device according to the predetermined communication method via the wireless interface by using the acquired public key, the target communication being a communication for establishing a wireless connection between a pair of devices according to the predetermined communication method; A computer program that functions as a (Item 8) The computer program further causes the computer to a display processing execution unit that executes a display process by using a first URI (short for Uniform Resource Identifier), the display process being a process of receiving first web page data for displaying a first web page from a server and displaying the first web page on the display unit, the first web page indicating a change operation for changing a state of the communication device from an impossible state in which wireless communication according to the specified communication method cannot be performed to a possible state in which wireless communication according to the specified communication method can be performed; 8. The computer program of claim 7, wherein the target communication is executed with the communication device after the state of the communication device is changed from the impossible state to the possible state due to the change operation indicated by the first web page being executed on the communication device. (Item 9) 9. The computer program product of claim 8, wherein the display process includes a process of receiving the first web page data from the server without using a browser program of the terminal, and a process of displaying the first web page on the display unit. (Item 10) the first URI includes the identification information; 10. The computer program product of item 8 or 9, wherein the first web page data includes a specific message corresponding to the communication device identified by the identification information. (Item 11) The computer program further causes the computer to Item 11. The computer program according to item 10, which causes the computer program to function as a first generation unit that generates the first URI including the domain of the server that the computer program has in advance and the identification information. (Item 12) 12. The computer program according to any one of items 7 to 11, wherein the public key acquisition unit acquires the public key by sending the identification information to the server with a second URI as a destination and receiving from the server the public key generated by the server from the identification information. (Item 13) The computer program further causes the computer to Item 13. The computer program according to item 12, further comprising a second generating unit configured to generate the second URI including the domain of the server and the identification information that the computer program has in advance. (Item 14) 14. The computer program of any one of claims 7 to 13, wherein the predetermined process includes supplying the public key to a connection program of the terminal to cause the connection program to execute the target communication with the communication device. (Item 15) Item 15. A computer program product according to any one of items 7 to 14, wherein the identification information comprises a serial number of the communication device. (Item 16) The target communication is transmitting an authentication request using the public key to the communication device; receiving an authentication response to the authentication request from the communication device; and transmitting connection information to the communication device; 16. The computer program according to any one of claims 7 to 15, wherein the connection information is information for establishing the wireless connection according to the specified communication method between the pair of devices, which are the communication device and an access point. (Item 17) A communication device, comprising: a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; a housing having a sticker attached thereto showing a code image obtained by encoding a character string, the character string not including a public key of the communication device but including identification information for identifying the communication device, the identification information being used by a terminal to obtain the public key; a communication execution unit that executes target communication with the terminal via the wireless interface in accordance with the predetermined communication method when the public key is acquired by the terminal, the target communication being communication for establishing a wireless connection between a pair of devices in accordance with the predetermined communication method; A communication device comprising: (Item 18) A communication device, comprising: a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; an output control unit that causes an output unit to output a code image obtained by encoding a character string, the character string not including a public key of the communication device but including identification information for identifying the communication device, the identification information being used by a terminal to obtain the public key; a communication execution unit that executes target communication with the terminal via the wireless interface in accordance with the predetermined communication method when the public key is acquired by the terminal, the target communication being communication for establishing a wireless connection between a pair of devices in accordance with the predetermined communication method; A communication device comprising: (Item 19) The character string includes a specific URI (short for Uniform Resource Identifier) ​​for downloading a vendor program provided by the vendor, 19. The communication device according to item 17 or 18, wherein the identification information is included in the specific URI. (Item 20) 19. A communication device according to any one of items 17 to 18, wherein the identification information includes a serial number of the communication device. (Item 21) The target communication is receiving an authentication request using the public key from the terminal; sending an authentication response to the authentication request to the terminal; and receiving connection information from the terminal; 21. The communication device according to any one of items 17 to 20, wherein the connection information is information for establishing the wireless connection according to the specified communication method between the pair of devices, which are the communication device and an access point. [Explanation of symbols]

[0084] 2: communication system, 6: AP, 10: terminal, 40: OS, 42: reading application, 44: browser application, 46: DL application, 48: connection application, 50: printer application, 100: printer, 100A: housing, 100B: sticker, 200, 270: server, 300: character string, 330, 340: URI, 350: public key, 400, 410, 420: web page

Claims

1. 1. A communication system comprising: A communication device; A terminal, A server, The terminal includes: Camera and a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; A display unit; A computer, a terminal memory for storing a code image reading program not provided by a vendor of the communication device and a browser program not provided by the vendor; The code image reading program controls the computer to operate as follows: a first character string acquisition unit that, when a code image is read by the camera, decodes the code image to acquire a character string, the character string not including a public key of the communication device and including a specific URI (short for Uniform Resource Identifier) ​​for downloading a vendor program provided by the vendor, the specific URI including identification information for identifying the communication device; a supply unit that supplies the acquired character string to the browser program; The browser program causes the computer to a first receiving unit that, when the character string is acquired from the code image reading program, receives, from the server, specific web page data for displaying a specific web page for downloading the vendor program, by using the specific URI included in the character string; a first display control unit that uses the specific web page data to display the specific web page on the display unit; After the vendor program is downloaded due to the specific web page being displayed on the display unit, the vendor program controls the computer to include the following units: a second character string acquisition unit that decodes the code image and acquires the character string when the code image is read again by the camera; a public key acquisition unit that acquires the public key of the communication device by using the identification information in the specific URI included in the acquired character string; a predetermined processing execution unit that executes a predetermined process for executing target communication with the communication device according to the predetermined communication method via the wireless interface by using the acquired public key, the target communication being communication for establishing a wireless connection between a pair of devices according to the predetermined communication method; Communication systems.

2. The vendor program further configures the computer to include the following units: a display processing execution unit that executes a display process by using a first URI different from the specific URI, the display process being a process of receiving first web page data for displaying a first web page from the server and displaying the first web page on the display unit, the first web page indicating a change operation for changing a state of the communication device from an impossible state in which wireless communication according to the specified communication method cannot be performed to a possible state in which wireless communication according to the specified communication method can be performed; The communication system of claim 1 , wherein the target communication is performed with the communication device after the state of the communication device is changed from the impossible state to the possible state due to the change operation indicated by the first web page being performed on the communication device.

3. The first URI includes the identification information in the specific URI included in the acquired character string, the display process includes a process of transmitting a web page request to the server with the first URI as a destination; The server, a server memory for storing, for each of a plurality of types of devices, a message indicating a change operation for changing the state of the device from the disabled state to the enabled state; an extractor for extracting, when the web page request is received from the terminal, from the server memory, a specific message corresponding to the communication device identified by the identification information included in the first URI; a web page sending unit that sends the first web page data including the extracted specific message to the terminal; The communication system of claim 2 .

4. 4. A communication system according to claim 1, wherein the public key acquisition unit acquires the public key by sending the identification information to the server with a second URI different from the specific URI as a destination, and receiving from the server the public key generated from the identification information by the server.

5. The terminal memory further stores a download program not provided by a vendor of the communication device; The download program controls the computer to operate as follows: a second receiving unit that receives, when a first operation for downloading the vendor program is executed on the specific web page, second web page data for displaying a second web page for downloading the vendor program from a server different from the server; a second display control unit that uses the second web page data to display the second web page on the display unit; a download unit that downloads the vendor program when a second operation for downloading the vendor program is executed on the second web page; The communication system according to claim 1 , wherein the communication system functions as follows:

6. The terminal memory further stores a connectivity program not provided by a vendor of the communication device; The communication system according to claim 1 , wherein the predetermined process includes supplying the public key to the connection program in order to cause the connection program to execute the target communication with the communication device.

7. A computer program for a terminal, comprising: The terminal includes: Camera and a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; A display unit; A computer, The computer program causes the computer to operate in the following manner: a character string acquisition unit that, when a code image is read by the camera, decodes the code image to acquire a character string, the character string not including a public key of a communication device and including identification information for identifying the communication device; a display processing execution unit that executes a display process by utilizing a first URI (short for Uniform Resource Identifier), the display process being a process of receiving first web page data for displaying a first web page from a server and displaying the first web page on the display unit, the first web page indicating a change operation for changing a state of the communication device from an impossible state in which wireless communication according to the specified communication method cannot be performed to a possible state in which wireless communication according to the specified communication method can be performed; a public key acquisition unit that acquires the public key of the communication device by using the identification information included in the acquired character string; a predetermined processing execution unit that executes a predetermined process for executing a target communication with the communication device according to the predetermined communication method via the wireless interface by using the acquired public key, the target communication being a communication for establishing a wireless connection between a pair of devices according to the predetermined communication method; A computer program that functions as a

8. 8. The computer program product according to claim 7, wherein the display process includes a process of receiving the first web page data from the server without using a browser program of the terminal, and a process of displaying the first web page on the display unit.

9. the first URI includes the identification information; The computer program product of claim 7 or 8, wherein the first web page data includes a specific message corresponding to the communication device identified by the identification information.

10. The computer program further causes the computer to The computer program according to claim 9 , further comprising a first generating unit configured to generate the first URI including a domain of the server that the computer program has in advance and the identification information.

11. A computer program for a terminal, comprising: The terminal includes: Camera and a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; A display unit; A computer, The computer program causes the computer to operate in the following manner: a character string acquisition unit that, when a code image is read by the camera, decodes the code image to acquire a character string, the character string not including a public key of a communication device and including identification information for identifying the communication device; a public key acquisition unit that acquires the public key of the communication device by using the identification information included in the acquired character string; a predetermined processing execution unit that executes a predetermined process for executing a target communication with the communication device according to the predetermined communication method via the wireless interface by using the acquired public key, the target communication being a communication for establishing a wireless connection between a pair of devices according to the predetermined communication method; Function as a The target communication is transmitting an authentication request using the public key to the communication device; receiving an authentication response to the authentication request from the communication device; and transmitting connection information to the communication device; the connection information is information for establishing the wireless connection between the pair of devices, that is, the communication device and the access point, in accordance with the predetermined communication method; Computer program.

12. 12. A computer program product according to claim 7, wherein the public key acquisition unit acquires the public key by sending the identification information to a server with a second URI as a destination and receiving from the server the public key generated by the server from the identification information.

13. The computer program further causes the computer to The computer program according to claim 12 , further comprising a second generating unit configured to generate the second URI including a domain of the server that the computer program has in advance and the identification information.

14. The computer program product according to claim 7 , wherein the predetermined process includes supplying the public key to a connection program of the terminal in order to cause the connection program to execute the target communication with the communication device.

15. A computer program product as claimed in any one of claims 7 to 14, wherein the identification information comprises a serial number of the communication device.

16. A communication device, comprising: a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; a housing having a sticker attached thereto showing a code image obtained by encoding a character string, the character string not including a public key of the communication device but including identification information for identifying the communication device, the identification information being used by a terminal to obtain the public key; a communication execution unit that executes target communication with the terminal via the wireless interface in accordance with the predetermined communication method when the public key is acquired by the terminal, the target communication being communication for establishing a wireless connection between a pair of devices in accordance with the predetermined communication method; Equipped with The target communication is receiving an authentication request using the public key from the terminal; sending an authentication response to the authentication request to the terminal; and receiving connection information from the terminal; the connection information is information for establishing the wireless connection between the pair of devices, that is, the communication device and the access point, in accordance with the predetermined communication method; Communications equipment.

17. A communication device, comprising: a wireless interface for performing wireless communication according to a predetermined communication method of the Wi-Fi standard; an output control unit that causes an output unit to output a code image obtained by encoding a character string, the character string not including a public key of the communication device but including identification information for identifying the communication device, the identification information being used by a terminal to obtain the public key; a communication execution unit that executes target communication with the terminal via the wireless interface in accordance with the predetermined communication method when the public key is acquired by the terminal, the target communication being communication for establishing a wireless connection between a pair of devices in accordance with the predetermined communication method; Equipped with The target communication is receiving an authentication request using the public key from the terminal; sending an authentication response to the authentication request to the terminal; and receiving connection information from the terminal; the connection information is information for establishing the wireless connection between the pair of devices, that is, the communication device and the access point, in accordance with the predetermined communication method; Communications equipment.

18. the character string includes a specific URI (short for Uniform Resource Identifier) ​​for downloading a vendor program provided by a vendor of the communication device, The communication device according to claim 16 or 17, wherein the identification information is included in the specific URI.

19. 19. A communication device according to any one of claims 16 to 18, wherein the identification information comprises a serial number of the communication device.

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