Communication device, computer program for communication device, and method performed by communication device

Abstract

To provide a technique that allows authentication using appropriate key information to be performed.SOLUTION: A communication device that operates according to a predetermined authentication method that uses a pair of keys is disclosed. In a specific state in which multiple pieces of user identification information and multiple pieces of key information corresponding to the multiple pieces of user identification information are stored in a first memory in association with one piece of biometric authentication information, the communication device acquires two or more user names and displays a first selection screen on a display unit. In response to transmitting an authentication request to a server, the communication device receives verification information from the server. When authentication of a target user is successful, a specific user name is selected on the first selection screen, and the verification information is received from the server, the communication device acquires signature information generated by encrypting the verification information using a specific private key, and transmits the selected specific user identification information and the generated signature information to the server.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] This specification discloses a technique for a communication device that operates according to a predetermined authentication method that uses a pair of keys. [Background technology]

[0002] Patent Document 1 discloses a system including an MFP, a mobile terminal, and a print system. When the mobile terminal receives an authentication request from the MFP, it executes a biometric authentication process. When the biometric authentication process is successful, the mobile terminal transmits assertion information to the MFP, the assertion information being composed of an authentication information ID and a signature encrypted with a private key corresponding to the user's biometric authentication information. The MFP transmits the assertion information to the print system. The print system verifies the validity of the assertion information by decrypting the assertion information using a public key corresponding to the authentication information ID. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-198400 A Summary of the Invention [Problem to be solved by the invention]

[0004] The system of Patent Document 1 does not take into consideration the case where a plurality of authentication information IDs are stored in association with one piece of biometric authentication information.

[0005] This specification provides a technique that can perform authentication using appropriate key information. [Means for solving the problem]

[0006] This specification discloses a communication device that operates according to a predetermined authentication method using a pair of keys. The communication device includes a display unit, an acquisition unit that acquires two or more user names corresponding to two or more user identification information among the plurality of user identification information in a specific state in which a first memory stores a plurality of pieces of user identification information associated with one piece of biometric authentication information, a first display control unit that causes the display unit to display a first selection screen for selecting one user name from the two or more acquired user names, a verification information receiving unit that receives verification information from the server in response to transmitting an authentication request to the server, and a verification information receiving unit that receives a verification information from the server in response to transmitting an authentication request to the server in response to transmitting a verification information ... the signature information acquisition unit acquires signature information generated by encrypting the verification information using a specific private key when a specific user name is selected and the verification information is received from the server, the specific private key being a key corresponding to specific key information stored in the first memory in association with specific user identification information corresponding to the selected specific user name; and a signature information transmission unit transmits the selected specific user identification information and the generated signature information to the server, the server decrypting the signature information using a specific public key stored in the server in association with the specific user identification information.

[0007] According to the above configuration, the communication device displays a first selection screen for selecting one user name from two or more user names. Therefore, the target user can select a specific user name corresponding to specific user identification information stored in association with specific key information to be used for authentication. Therefore, authentication can be performed using the specific key information corresponding to the specific user name selected by the user.

[0008] A computer program for the above-mentioned communication device, a computer-readable recording medium storing the computer program, and a method executed by the communication device are also novel and useful. Also, a communication system including the communication device and a server is novel and useful. [Brief description of the drawings]

[0009] [Figure 1] 1 shows the configuration of a communication system. [Diagram 2] An example of each table is shown below. [Diagram 3] FIG. 11 is a sequence diagram of case A in which a print file is uploaded to a server. [Figure 4] This is a continuation of the sequence diagram of Figure 3. [Diagram 5] FIG. 13 is a sequence diagram of a case B in which print data is downloaded from a server. [Figure 6] 6 is a continuation of the sequence diagram in FIG. 5 and a sequence diagram for case C in which printing fails. [Figure 7] 13 is a sequence diagram of cases D and E in which printing fails, and case F in which the authentication device is removed during printing. [Figure 8] FIG. 13 is a sequence diagram of case G in which a print file is uploaded to a server. [Figure 9] This is a continuation of the sequence diagram of FIG. [Figure 10] FIG. 13 is a sequence diagram of case H in which print data is downloaded from a server. [Figure 11] This is a continuation of the sequence diagram in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (Example) (Configuration of communication system 2; Figure 1) 1, the communication system 2 includes a printer 10, authenticators 50A and 50B, a PC 100, and a server 200. The printer 10, the PC 100, and the server 200 are connected to the Internet 6. The printer 10, the PC 100, and the server 200 are capable of communicating with each other via the Internet 6.

[0011] (Printer 10 Configuration) The printer 10 is a peripheral device (for example, a peripheral device of the PC 100) capable of executing a printing function. In a modified example, the printer 10 may be a multi-function device capable of executing a scanning function, a fax function, and the like in addition to a printing function. The printer 10 is operable according to a FIDO (short for Fast Identity Online) authentication method that uses a pair of keys. The FIDO authentication method is an authentication method that uses a pair of keys, that is, a private key and a public key. The FIDO authentication method is also an authentication method that performs user authentication using biometric authentication (for example, fingerprint authentication, voiceprint impression, face authentication) instead of authentication using a password. Hereinafter, authentication according to the FIDO authentication method will be referred to as "FIDO authentication".

[0012] The printer 10 includes an operation unit 12, a display unit 14, a print execution unit 16, a USB interface 18, a communication interface 20, and a control unit 30. In the following, the interface will be referred to as "I / F".

[0013] The operation unit 12 is an interface for inputting various information to the printer 10, and includes buttons, a touch screen, and the like. The display unit 14 is a display or panel for displaying various information. The panel may or may not be a touch panel. The panel is, for example, a liquid crystal panel or an organic EL panel. The print execution unit 16 has an electrophotographic, inkjet, or thermal print engine. The USB I / F 18 is an I / F to which a USB connector is connected. The communication I / F 20 is an interface for executing communication with other devices. The communication I / F 20 is connected to the Internet 6. The communication I / F 20 may be a wired I / F or a wireless I / F.

[0014] The control unit 30 includes a CPU 32, a volatile memory 34, and a non-volatile memory 36. The volatile memory 34 includes a RAM. The non-volatile memory 36 includes a Hard Disk Drive (HDD) and a ROM. The non-volatile memory 36 may include a Solid State Drive (SSD) or a flash memory. The non-volatile memory 36 stores a program 40 and installation information 42. The program 40 stored in the non-volatile memory 36 is loaded into the volatile memory 34 and executed, thereby executing various processes. The installation information 42 is information indicating the location where the printer 10 is installed. The installation information 42 stores any one of information "PUBLIC" indicating that the printer 10 is installed in a location such as a convenience store that is available to an unspecified number of people (for example, a convenience store), "OFFICE" indicating that the printer 10 is installed in a location such as an office that is available to a specified number of people (for example, an office), and "HOME" indicating that the printer 10 is installed in a private home. The installation information 42 can be set by an administrator of the printer 10.

[0015] (Configuration of authenticators 50A and 50B) The authentication devices 50A and 50B can operate according to the FIDO authentication method. The authentication devices 50A and 50B operate as so-called authentication devices in the FIDO authentication method. The authentication device 50A includes a USB cable (not shown) having a USB connector, and a non-volatile memory 60A. The non-volatile memory 60A stores fingerprint information 62A, an authentication table 64A, support information, and the serial number "SN1" of the authentication device 50A. The authentication table 64A is stored in association with the fingerprint information 62A. The fingerprint information 62A is information on the fingerprint of a user who uses the PC 100. In the following, the user who uses the PC 100 may be referred to as a "target user". The support information is information indicating whether the authentication device supports user nameless authentication. User nameless authentication refers to authentication that does not require input of a user name when logging in to a server that provides a service. The authentication device 50A supports user nameless authentication. For this reason, the support information in the non-volatile memory 60A stores "ON", which indicates that the authentication device 50A supports user-nameless authentication.

[0016] The authentication device 50B includes a USB cable (not shown) having a USB connector, and a non-volatile memory 60B. The non-volatile memory 60B stores fingerprint information 62B, an authentication table 64B, support information, and the serial number "SN2" of the authentication device 50B. The authentication table 64B is stored in association with the fingerprint information 62B. The fingerprint information 62B is information relating to the fingerprint of the target user. The authentication device 50B does not support user-nameless authentication. For this reason, "OFF" is stored in the support information in the non-volatile memory 60B, which indicates that the authentication device 50B does not support user-nameless authentication.

[0017] (PC100 configuration) The PC 100 may be a desktop PC or a notebook PC. The PC 100 is operable according to the FIDO authentication method. The PC 100 includes an operation unit 112, a display unit 114, a USB I / F 118, a communication I / F 120, and a control unit 130.

[0018] The operation unit 112 is an interface for inputting various information to the PC 100, and includes a mouse, a keyboard, and the like. The display unit 114 is a display or panel for displaying various information. The USB I / F 118 is an I / F to which a USB connector is connected. The communication I / F 120 is an interface for executing communication with other devices. The communication I / F 120 is connected to the Internet 6. The communication I / F 120 may be a wired I / F or a wireless I / F.

[0019] The control unit 130 includes a CPU 132, a volatile memory 134, and a non-volatile memory 136. The non-volatile memory 136 stores an Operating System (OS) program 140. The OS program 140 controls the basic operations of the PC 100. The OS program 140 stored in the non-volatile memory 136 is loaded into the volatile memory 134 and executed, thereby performing various processes.

[0020] (Configuration of Server 200) Server 200 is a server installed on the Internet 6, and is provided by, for example, a vendor of printer 10. In a modified example, server 200 may be installed on the Internet 6 by a business entity other than the vendor. In another modified example, the vendor may not prepare the hardware for server 200 by itself, but may use an environment provided by an external cloud computing service. In this case, the vendor may prepare a program (i.e., software) for server 200 and implement the program in the above-mentioned environment to realize server 200.

[0021] The server 200 can operate according to the FIDO authentication method. The server 200 operates as a so-called authentication server in the FIDO authentication method, and also operates as a so-called intermediary server that mediates printing by the printer 10. That is, the server 200 provides a service that mediates printing by the printer 10. In response to successful user authentication according to the FIDO authentication, the server 200 permits uploading of print data to the server 200 and downloading of print data stored in the server 200.

[0022] The server 200 includes a communication I / F 220 and a control unit 230. The communication I / F 220 is connected to the Internet 6. The control unit 230 includes a CPU 232, a volatile memory 234, and a non-volatile memory 236. The non-volatile memory 236 stores a program 240 and a management table 242. The program 240 stored in the non-volatile memory 236 is loaded into the volatile memory 234 and executed, thereby performing various processes.

[0023] (Table composition; Fig. 2) Referring to FIG. 2, an authentication table 64A in the authentication device 50A, an authentication table 64B in the authentication device 50B, and a management table 242 in the server 200 will be described.

[0024] In the authentication table 64A of the authentication device 50A supporting the user nameless authentication, the RPID, the key ID, the user ID, the private key, and the user name are stored in association with each other. Each piece of information in the authentication table 64A is registered when a registration process for registering a pair of keys used in FIDO authentication is executed. The RPID is an ID for identifying the server. In this embodiment, the RPID is a URL. The key ID is information for managing the key used in FIDO authentication. The user ID is information for managing the user, and is information generated by the server 200. The private key is information used when executing FIDO authentication. The key ID and the private key are generated by the authentication device in the registration process. Specifically, the authentication device generates a pair of keys (i.e., a private key and a public key) using the RPID and the key ID. The key ID and the private key in the authentication table 64A are generated by the authentication device 50A. The user name is information set by the user to log in to the server 200. The user name is a so-called login name.

[0025] In the authentication table 64B of the authenticator 50B that does not support user nameless authentication, the RPID, the key ID, and the user ID are stored in association with each other. The information stored in the authentication table 64B is the same as the information stored in the authentication table 64A, except that it does not include the private key and the user name. The key ID in the authentication table 64B is generated by the authenticator 50B.

[0026] In the management table 242 of the server 200, an RPID, a key ID, a user ID, a public key, a user name, a job ID, and a serial number are stored in association with each other. The RPID, the key ID, the user ID, the public key, and the user name in the management table 242 are registered when a registration process is executed. The public key is information used when executing FIDO authentication. The public key is generated by an authenticator in the registration process. The job ID and the serial number are registered when an upload process is executed to upload print data to the server 200. The job ID is information for identifying the print data. Although not shown in the figure, the print data is associated with the job ID and stored in the non-volatile memory 236.

[0027] (Specific cases A to H) 3 to 11, specific cases A to H realized by the communication system 2 of the present embodiment will be described. In cases A to F in FIG. 3 to FIG. 7, the authenticator 50A supporting the user nameless authentication is used, and in cases G and H in FIG. 8 to FIG. 11, the authenticator 50B not supporting the user nameless authentication is used. In the following, the CPU of each device (for example, the CPU 32 of the printer 10) is not described as the subject, but each device (for example, the printer 10) is described as the subject. In addition, communication between the printer 10, the PC 100, and the server 200 is performed via the communication I / F of each device (for example, the communication I / F 20 of the printer 10). Therefore, in the following, when describing the process related to the communication via the communication I / F, the description "via the communication I / F" is omitted. In addition, communication between the printer 10 and the authenticators 50A and 50B is performed via the USB I / F of each device (for example, the USB I / F 18 of the printer 10). For this reason, in the following, when describing processing related to communication via the USB I / F, the phrase "via the USB I / F" will be omitted.

[0028] (Case A; Figures 3 and 4) 3 and 4, a case A in which print data is uploaded to the server 200 in response to successful user authentication by FIDO authentication will be described. In the initial state of case A, in the authentication table 64A of the authentication device 50A, the RPID "URL1", the key ID "KEYID1", the user ID "user1", the private key PRK1, and the user name "aaa_company" are stored in association with each other, and the RPID "URL1", the key ID "KEYID2", the user ID "user2", the private key PRK2, and the user name "aaa_home" are stored in association with each other. The URL1 is the URL of the server 200. That is, in the non-volatile memory 60A of the authentication device 50A, two user IDs and two key IDs corresponding to the two user IDs are stored in association with one fingerprint information 62A of the target user. In addition, in the management table 242 of the server 200, the RPID "URL1", the key ID "KEYID1", the user ID "user1", the public key PUK1, and the user name "aaa_company" are stored in association with each other, and the RPID "URL1", the key ID "KEYID2", the user ID "user2", the public key PUK2, and the user name "aaa_home" are stored in association with each other. The user name "aaa_company" and the user name "aaa_home" are user names used by the target user. The user name "aaa_company" is a user name used by the target user for work, and is used, for example, to log in to the server 200 at the target user's workplace. The user name "aaa_home" is a user name used by the target user for private use, and is used, for example, to log in to the server 200 at the target user's personal home.

[0029] At T10, the user connects the USB connector of the authenticator 50A to the USB I / F 118 of the PC 100. As a result, the PC 100 determines that the authenticator 50A is connected to the PC 100, and at T12, transmits a support information request to the authenticator 50A. The support information request is a signal for requesting the authenticator to transmit support information. At T14, the PC 100 receives the support information "ON" from the authenticator 50A. Since the received support information indicates "ON", the PC 100 determines that the connected authenticator 50A supports user-nameless authentication.

[0030] In T20, the target user executes a login operation without inputting a user name. Specifically, in a state where a login screen is displayed on the display unit 114 of the PC 100, the target user selects the login button in the login screen without inputting a user name. As a result, in T22, the PC 100 transmits to the server 200 an authentication request including, as an RPID, a URL1 that identifies the service (i.e., the intermediation service) used by the target user.

[0031] When the server 200 receives an authentication request from the PC 100 in T22, the server 200 generates a one-time pass OP1 in T24 and stores the one-time pass OP1 in the volatile memory 234. In T26, the server 200 transmits an authentication instruction including the RPID "URL1" and the one-time pass OP1 to the PC 100. The authentication instruction is a signal for instructing the execution of biometric authentication and the generation of signature information.

[0032] When the PC 100 receives an authentication instruction from the server 200 in T26, the PC 100 displays a fingerprint authentication screen in T28. The fingerprint authentication screen displays a message requesting execution of fingerprint authentication using the authentication device 50A.

[0033] At T30, the target user performs a fingerprint authentication operation on the authentication device 50A. Since the fingerprint information acquired by the fingerprint authentication operation matches the fingerprint information 62A in the non-volatile memory 60A, the authentication device 50A determines that the fingerprint authentication has been successful, and at T32, transmits to the PC 100 authentication success information indicating that the fingerprint authentication has been successful.

[0034] When the PC 100 receives authentication success information from the authentication device 50A at T32, it transmits a user name request including the RPID "URL1" to the authentication device 50A at T34. The user name request is a signal for requesting transmission of one or more user names stored in the authentication table 64A in association with the RPID included in the request.

[0035] When the authentication device 50A receives a user name request from the PC 100 in T34, it identifies the RPID "URL1" in the request, and identifies two user names "aaa_company" and "aaa_home" that are associated with the identified RPID "URL1" and stored in the authentication table 64A. In T36, the authentication device 50A transmits the identified user names "aaa_company" and "aaa_home" to the PC 100.

[0036] When the PC 100 receives the user names "aaa_company" and "aaa_home" from the authentication device 50A in T36, the PC 100 displays a user name selection screen including the user names "aaa_company" and "aaa_home" in T38. The user name selection screen is a screen for allowing the target user to select one user name. The target user selects the user name "aaa_company" in the user name selection screen in T40. This causes the PC 100 to transmit a signature information generation request including the selected user name "aaa_company" and the received one-time pass OP1 (see T26) to the authentication device 50A. The signature information generation request is a signal for requesting the generation of signature information. Note that when the PC 100 receives only one user name from the authentication device 50A, the PC 100 may transmit a signature information generation request including the user name and the one-time pass OP1 to the authentication device 50A without displaying the user name selection screen.

[0037] When the authenticator 50A receives a signature information generation request from the PC 100 in T42, the authenticator 50A identifies the private key PRK1 stored in the authentication table 64A in association with the user name "aaa_company" included in the request. In T44, the authenticator 50A generates signature information SI1 by encrypting the received one-time pass OP1 using the identified private key PRK1. The authenticator 50A identifies the user ID "user1" stored in the authentication table 64A in association with the received user name "aaa_company". In T46, the authenticator 50A transmits the identified user ID "user1" and the generated signature information SI1 to the PC 100.

[0038] When PC 100 receives user ID "user1" and signature information SI1 from authentication device 50A in T46, it transmits an authentication response including user ID "user1" and signature information SI1 to server 200 in T48.

[0039] When the server 200 receives the authentication response from the PC 100 in T48, the server 200 identifies the public key PUK1 stored in the management table 242 in association with the user ID "user1" in the response. In T50 of FIG. 4, the server 200 uses the identified public key PUK1 to decrypt the signature information SI1 in the authentication response. Since the private key PRK1 and the public key PUK1 are a pair of keys, the one-time pass OP1 is obtained by decrypting the signature information SI1 using the public key PUK1. The server 200 determines that the decrypted one-time pass OP1 matches the one-time pass OP1 stored in the volatile memory 234 (see T24 of FIG. 3), and determines that the user authentication of the user ID "user1" (i.e., the user name "aaa_company") has been successful. In this case, the server 200 transitions from a logged-out state to a logged-in state in T52. The server 200 transitioning to the logged-in state allows the target user to upload a print file to the server 200. At T54, the server 200 transmits to the PC 100 a notification of successful authentication indicating that the user authentication has been successful.

[0040] When PC 100 receives a successful authentication notification from server 200 in T54, it displays an authentication success screen in T56. This allows the target user to know that user authentication has been successful. The target user performs an upload operation on PC 100 in T60 to upload a print file (more specifically, print data) to server 200. In the upload operation, the target user selects the print file to be sent. This causes PC 100 to send an upload request to server 200 in T62, which includes the print file selected by the target user and the user ID "user1".

[0041] When the server 200 receives an upload request from the PC 100 in T62, in T64, the server 200 generates a job ID "job1" and converts the print file in the request to generate print data PD1 representing a print image having a data format that can be interpreted by the printer 10. In T66, the server 200 associates the generated job ID "job1" with the received user ID "user1" and stores it in the management table 242. The server 200 stores the print data PD1 in the non-volatile memory 236 in association with the job ID "job1". In T68, the server 200 transmits an upload completion notification to the PC 100 indicating that the upload of the print file to the server 200 has been completed.

[0042] When the PC 100 receives an upload completion notification from the server 200 in T68, the PC 100 displays an upload completion screen in T70. This allows the target user to know that uploading of the print file to the server 200 has been completed. The PC 100 transmits a logout request to the server 200 in T72.

[0043] When the server 200 receives a logout request from the PC 100 in T72, the server 200 transitions from a logged-in state to a logged-out state in T74. In this manner, the print file is uploaded to the server 200 in response to successful user authentication by FIDO authentication.

[0044] (Case B; Figures 5 and 6) 5 and 6, a case B in which print data is downloaded from the server 200 in response to successful user authentication by FIDO authentication will be described. The initial state of case B is the state after case A. That is, in the non-volatile memory 60A of the authentication device 50A, two user IDs and two key IDs corresponding to the two user IDs are stored in association with one piece of fingerprint information 62A of the target user.

[0045] In T110, the target user connects the USB connector of the authenticator 50A to the USB I / F 18 of the printer 10. As a result, the printer 10 determines that the authenticator 50A is connected to the printer 10, and in T112, sends a support information request to the authenticator 50A, and in T114, receives the support information "ON" from the authenticator 50A. Since the received support information indicates "ON", the PC 100 determines that the connected authenticator 50A supports user nameless authentication. In this case, in T122, the printer 10 sends an authentication request to the server 200, including URL1 pre-stored in the non-volatile memory 36 of the printer 10 as an RPID.

[0046] When the server 200 receives an authentication request from the printer 10 in T122, the server 200 generates a one-time pass OP2 in T124 and stores it in the volatile memory 234. In T126, the server 200 transmits an authentication instruction including the RPID “URL1” and the one-time pass OP2 to the printer 10.

[0047] T126 to T148 are the same as T26 to T48 in FIG. 3, respectively, except that the communication target is the printer 10 and the one-time pass OP2 is used. In T144 of this case, the authentication device 50A generates signature information SI2 by encrypting the received one-time pass OP2 using the private key PRK1. In T150 of FIG. 6, the server 200 obtains the one-time pass OP2 by decrypting the signature information SI2 using the public key PUK1. The server 200 determines that the decrypted one-time pass OP2 matches the one-time pass OP2 stored in the volatile memory 234, and determines that the user authentication of the user ID "user1" has been successful. In T152, the server 200 transitions from a logged-out state to a logged-in state. By the server 200 transitioning to the logged-in state, the target user can download the print data uploaded to the server 200. The server 200 identifies the job ID "job1" stored in the management table 242 in association with the authenticated user ID "user1", and transmits an authentication success notification including the identified job ID "job1" to the printer 10 in T154.

[0048] When the printer 10 receives a notification of successful authentication from the server 200 in T154, the printer 10 displays a job selection screen including the received job ID "job1" in T156, and stores the received job ID "job1" in the volatile memory 34. The job selection screen is a screen for allowing the target user to select one job ID. The target user selects the job ID "job1" in the job selection screen in T160. This causes the printer 10 to transmit a print data request including the selected job ID "job1" to the server 200 in T162.

[0049] When the server 200 receives a print data request from the printer 10 at T162, the server 200 identifies the print data PD1 stored in the non-volatile memory 236 in association with the job ID “job1” in the request, and at T164, transmits the identified print data PD1 to the printer 10.

[0050] When the printer 10 receives the print data PD1 from the server 200 in T164, in T166, the printer 10 stores the print data PD1 in the non-volatile memory 36 in association with the job ID "job1", and executes printing using the print data PD1. In this case, the printing using the print data PD1 is completed successfully. In this case, the printer 10 sends a print completion notification including the job ID "job1" to the server 200 in T168, and erases the job ID "job1" and the print data PD1 from the volatile memory 34 in T170.

[0051] When the server 200 receives a print completion notification from the printer 10 in T168, it deletes the job ID “job1” from the management table 242 and deletes the print data PD1 from the non-volatile memory 236 in T172.

[0052] Thereafter, in T180, the target user removes the authentication device 50A from the printer 10. As a result, the printer 10 determines that it has accepted a logout operation for logging out from the server 200, and in T182, transmits a logout request to the server 200.

[0053] When the server 200 receives a logout request from the printer 10 in T182, the server 200 transitions from a logged-in state to a logged-out state in T184. In this manner, printing using FIDO authentication is performed.

[0054] (Case C; Figure 6) 6, a case C will be described in which printing using print data PD1 fails due to an error occurring in printer 10 when "PUBLIC" is stored in installation information 42 of printer 10. The error may be, for example, a lack of printing paper. The initial state of case C is the same as the initial state of case B in FIGS. 5 and 6.

[0055] First, the same processes as T110 to T148 in FIG. 5 and T150 to T166 in FIG. 6 are executed between the authenticator 50A, the printer 10, and the server 200. The printer 10 determines that printing has failed in T268. The target user removes the authenticator 50A from the printer 10 in T270. As a result, the printer 10 determines that a logout operation for logging out from the server 200 has been accepted. The printer 10 also determines in T272 that the installation information 42 indicates "PUBLIC". In this case, the printer 10 executes a first logout process. Specifically, the printer 10 stops printing in T272, transmits a logout request to the server 200 in T274, and stops printing using the print data PD1 in T276, and erases the job ID "job1" and the print data PD1 from the volatile memory 34. T280 is the same as T184. After that, when the error in the printer 10 is resolved by the target user loading new print paper in the printer 10 and the authentication device 50A is connected to the printer 10, the processing from T112 onwards in FIG. 5 is executed again.

[0056] (Case D; Figure 7) 7, a case D will be described in which printing using print data PD1 fails due to an error occurring in printer 10 when "OFFICE" is stored in installation information 42 of printer 10. The initial state of case D is the same as the initial state of case B in FIGS.

[0057] First, the same processes as T110 to T148 in FIG. 5 and T150 to T166, T268, and T270 in FIG. 6 are executed between the authenticator 50A, the printer 10, and the server 200. The printer 10 determines that the installation information 42 indicates "OFFICE" in T372. In this case, the printer 10 executes the second logout process. Specifically, the printer 10 stops printing in T374, and transmits a logout request to the server 200 in T376. That is, the printer 10 does not erase the job ID "job1" and the print data PD1 from the volatile memory 34. T378 is the same as T184 in FIG. 6. After that, when the error in the printer 10 is resolved and the authenticator 50A is connected to the printer 10, the processes from T112 onward in FIG. 5 are executed. 6 are omitted because the job ID "job1" and the print data PD1 are stored in the non-volatile memory 36. In a modified example, only T162 and T164 in FIG.

[0058] (Case E; Figure 7) 7, a case E will be described in which printing using print data PD1 fails due to an error occurring in printer 10 when "HOME" is stored in installation information 42 of printer 10. The initial state of case E is the same as the initial state of case B in FIGS.

[0059] First, the same processes as T110 to T148 in FIG. 5 and T150 to T166, T268, and T270 in FIG. 6 are executed between the authentication device 50A, the printer 10, and the server 200. The printer 10 determines that the installation information 42 indicates "HOME" in T472. In this case, the printer 10 executes the third logout process. Specifically, the printer 10 interrupts printing in T474. That is, the printer 10 does not stop printing. The printer 10 further transmits a logout request to the server 200 in T476. T478 is the same as T184 in FIG. 6. After that, when new printing paper is set in the printer 10 by the target user, the printer 10 determines that the error has been resolved in T480, and resumes printing using the print data PD1 in T482. When printing is completed, the same processes as T168 to T172 in FIG. 6 are executed. In a modified example, the printer 10 may transmit a logout request to the server 200 after printing is completed, instead of T476, that is, after T170 in FIG. 6 cited in case E in FIG.

[0060] As shown in cases C to E, the printer 10 is configured to execute one of the first logout process, the second logout process, and the third logout process when printing fails. With this configuration, the printer 10 can execute an appropriate logout process from the first logout process, the second logout process, and the third logout process.

[0061] The printer 10 executes a first logout process when "PUBLIC" is stored in the installation information 42 (case C in FIG. 6), executes a second logout process when "OFFICE" is stored in the installation information 42 (case D in FIG. 7), and executes a third logout process when "HOME" is stored in the installation information 42 (case E in FIG. 7). When "PUBLIC" is stored in the installation information 42, it is highly likely that the next user who uses the printer 10 is a third party unrelated to the target user. In such a situation, it is undesirable from the viewpoint of security that the server 200 is maintained in a logged-in state and the job ID "job1" remains in the printer 10 after the authentication device 50A is removed from the printer 10. In addition, when "OFFICE" is stored in the installation information 42, it is highly likely that the next user who uses the printer 10 is a colleague of the target user. In such a situation, even if the job ID "job1" remains in the printer 10, there is little security problem. Furthermore, if "HOME" is stored in the installation information 42, there is a high possibility that the target user will use the printer 10 next. In such a situation, even if printing is resumed after the authentication device 50A is removed from the printer 10, there is little security problem. In this way, the printer 10 can execute an appropriate logout process according to the information stored in the installation information 42.

[0062] (Case F; Figure 7) 7, a case F in which the authentication device 50A is removed from the printer 10 during printing using the print data PD1 will be described. The initial state of case F is similar to the initial state of case B in FIGS.

[0063] First, the same processes as T110 to T148 in FIG. 5 and T150 to T166 in FIG. 6 are executed between the authenticator 50A, the printer 10, and the server 200. The target user removes the authenticator 50A from the printer 10 at T568 while printing using the print data PD1 is being executed. In this case, the printer 10 determines that a logout operation for logging out from the server 200 has been accepted, but continues printing using the print data PD1 at T570, and transmits a logout request to the server 200 at T572. T574 is the same as T184 in FIG. 6. When printing is completed, the printer 10 transmits a print completion notification including the job ID "job1" to the server 200 at T580, and erases the job ID "job1" and the print data PD1 from the volatile memory 34 at T582. T584 is the same as T172 in FIG. 6. In a modified example, the printer 10 may transmit a logout request to the server 200 after printing is completed, that is, after T582, instead of T572.

[0064] As described above, even if the authenticator 50A is removed from the printer 10 during printing, the printer 10 does not stop printing. Even if the printer 10 is currently printing, the target user may mistakenly believe that printing is complete and remove the authenticator 50A from the printer 10. With the above configuration, since the printer 10 does not stop printing, printing is properly completed even if the target user mistakenly removes the authenticator 50A from the printer 10. This improves convenience for the target user.

[0065] (Case G; Figures 8 and 9) 8 and 9, a case G in which print data is uploaded to the server 200 in response to successful user authentication by FIDO authentication will be described. In the initial state of case G, in the authentication table 64B of the authentication device 50B, the RPID "URL1", the key ID "KEYID1", and the user ID "user1" are stored in association with each other, and the RPID "URL1", the key ID "KEYID2", and the user ID "user2" are stored in association with each other. That is, in the non-volatile memory 60B of the authentication device 50B, two user IDs and two key IDs corresponding to the two user IDs are stored in association with one fingerprint information 62B of the target user. In addition, in management table 242 of server 200, the RPID "URL1", key ID "KEYID1", user ID "user1", public key PUK1, and user name "aaa_company" are stored in association with each other, and the RPID "URL1", key ID "KEYID2", user ID "user2", public key PUK2, user name "aaa_home", job ID "job2", and serial number "SN2" are stored in association with each other.

[0066] At T610, the target user connects the USB connector of the authenticator 50B to the USB I / F 118 of the PC 100. As a result, the PC 100 determines that the authenticator 50B is connected to the PC 100, and at T612, it transmits a support information request to the authenticator 50B, and at T614, it receives the support information "OFF" and the serial number "SN2" from the authenticator 50B. Since the received support information indicates "OFF", the PC 100 determines that the connected authenticator 50B does not support user nameless authentication.

[0067] The target user executes a login operation of inputting the user name "aaa_company" in T620. Specifically, in a state where a login screen is displayed on the display unit 114 of the PC 100, the target user inputs the user name "aaa_company" and selects the login button in the login screen. As a result, the PC 100 transmits the RPID "URL1" and the input user name "aaa_company" to the server 200 in T622.

[0068] When the server 200 receives an authentication request from the PC 100 in T622, the server 200 generates a one-time pass OP3 in T624 and stores the one-time pass OP3 in the volatile memory 234. The server 200 identifies the user ID "user1" stored in the management table 242 in association with the user name "aaa_company" in the authentication request, and transmits an authentication instruction including the RPID "URL1", the one-time pass OP3, and the user ID "user1" to the PC 100 in T626. T628 is the same as T28 in FIG. 3.

[0069] In T630, the target user performs a fingerprint authentication operation on the authentication device 50B. Since the fingerprint information acquired by the fingerprint authentication operation matches the fingerprint information 62B in the non-volatile memory 60B, the authentication device 50B determines that the fingerprint authentication has been successful, and in T632, transmits authentication success information to the PC 100.

[0070] When the PC 100 receives authentication success information from the authentication device 50B in T632, the PC 100 transmits a signature information generation request including the user ID "user1" and the one-time pass OP3 to the authentication device 50B in T634.

[0071] When the authenticator 50B receives a signature information generation request from the PC 100 in T634, the authenticator 50B identifies the RPID "URL1" and the key ID "KEYID1" stored in the authentication table 64B in association with the user ID "user1" included in the request. The authenticator 50B generates a private key using the identified RPID "URL1" and the key ID "KEYID1". The private key generated in this case is the private key PRK1 corresponding to the public key PUK1 stored in the management table 242 of the server 200. The authenticator 50B generates signature information SI3 by encrypting the received one-time pass OP3 using the generated private key PRK1 in T636, and transmits the generated signature information SI3 to the PC 100 in T638.

[0072] When PC 100 receives signature information SI3 from authentication device 50B in T638, it transmits an authentication response including the user ID "user1" and signature information SI3 to server 200 in T640.

[0073] When the server 200 receives the authentication response from the PC 100 at T640, it obtains a one-time pass OP3 by decrypting the signature information SI3 in the authentication response using the public key PUK1 at T650 in Fig. 9. The server 200 determines that the decrypted one-time pass OP3 matches the one-time pass OP3 stored in the volatile memory 234, and determines that the user authentication of the user ID "user1" has been successful. T652 to T660 are the same as T52 to T60 in Fig. 4.

[0074] In T662, the PC 100 transmits to the server 200 an upload request including the print file selected by the target user and the received serial number "SN2" (see T614 in FIG. 8).

[0075] When the server 200 receives an upload request from the PC 100 in T662, the server 200 generates a job ID "job3" and generates print data PD3 in T664. In T666, the server 200 associates the generated job ID "job3" and the received serial number "SN2" with the received user ID "user1" in the management table 242. The server 200 stores the print data PD3 in the non-volatile memory 236 in association with the job ID "job3". T668 to T674 are the same as T68 to T74 in FIG. 4. In this way, in response to successful user authentication by FIDO authentication, the print file is uploaded to the server 200.

[0076] (Case H; Figures 10 and 11) 10 and 11, a case H in which print data is downloaded from the server 200 in response to successful user authentication by FIDO authentication will be described. The initial state of case H is the state after case G. That is, in the non-volatile memory 60B of the authentication device 50B, two user IDs and two key IDs corresponding to the two user IDs are stored in association with one piece of fingerprint information 62B of the target user.

[0077] In T710, the target user connects the USB connector of the authenticator 50B to the USB I / F 18 of the printer 10. As a result, the printer 10 determines that the authenticator 50B is connected to the printer 10, transmits a support information request to the authenticator 50B in T712, and receives the support information "OFF" and the serial number "SN2" from the authenticator 50B in T714. Since the received support information indicates "OFF", the PC 100 determines that the connected authenticator 50B does not support user-nameless authentication. In this case, the printer 10 transmits a user name request including the received serial number "SN2" to the server 200 in T720. The user name request is a signal for requesting the server 200 to transmit the user name stored in the management table 242 in association with the serial number "SN2" in the request. In this way, the printer 10 transmits a user name request to the server 200 when the authenticator connected to the printer 10 does not support user-nameless authentication. On the other hand, if the authenticator connected to the printer 10 supports user-nameless authentication, the printer 10 sends a user-name request to the authenticator (see T134 in FIG. 5).

[0078] When the server 200 receives the user name request from the printer 10 in T720, the server 200 identifies the user names "aaa_company" and "aaa_home" that are associated with the serial number "SN2" in the request and stored in the management table 242. The server 200 transmits the user names "aaa_company" and "aaa_home" to the printer 10 in T722.

[0079] When the printer 10 receives the user names "aaa_company" and "aaa_home" from the server 200 in T722, the printer 10 displays a user name selection screen including the user names "aaa_company" and "aaa_home" in T724. The user selects the user name "aaa_company" in the user name selection screen in T726. This causes the printer 10 to transmit an authentication request including the RPID "URL1" and the selected user name "aaa_company" to the server 200. As described above, the printer 10 transmits a user name request including the serial number "SN2" to the server 200, so that it is possible to prevent a user name stored in the management table 242 in association with a serial number different from the serial number "SN2" from being transmitted to the printer 10. This makes it possible to reduce the number of user names displayed on the user name selection screen. This improves the convenience of the target user.

[0080] When the server 200 receives an authentication request from the printer 10 in T728, it generates a one-time pass OP4 in T730 and stores the one-time pass OP4 in the volatile memory 234. T732, T734, and T740 to T744 are similar to T626, T628, and T640 to T644 in Fig. 8, respectively, except that the communication target is the printer 10 and that the one-time pass OP4 is used.

[0081] The authenticator 50B generates a private key using the RPID "URL1" and key ID "KEYID1" in the authentication table 64B, and in T746 generates signature information SI4 by encrypting the received one-time pass OP4 using the generated private key. T748, T750, and T760 and T762 in Fig. 11 are similar to T638 and T640 in Fig. 8 and T650 and T652 in Fig. 9, respectively, except that the communication target is the printer 10 and that the one-time pass OP4 is used.

[0082] T764 to T782 are the same as T154 to T172 in FIG. 6, except that the job ID "job3" and print data PD3 are used.

[0083] In T790, the target user removes the authentication device 50B from the printer 10. As a result, the printer 10 determines that a logout operation for logging out from the server 200 has been accepted, and in T792, transmits a logout request to the server 200. T794 is the same as T184 in Fig. 6. In this manner, printing using FIDO authentication is performed.

[0084] (Effects of this embodiment) According to the above configuration, the printer 10 displays a user name selection screen for selecting one user name from two or more user names (T138 in FIG. 5, T724 in FIG. 10). Therefore, the target user can select the user name "aaa_company" corresponding to the user ID "user1" stored in association with the key ID "KEY1" to be used for authentication (T140 in FIG. 5, T726 in FIG. 10). Therefore, authentication can be performed using the key ID "KEY1" corresponding to the user name "aaa_company" selected by the target user. Furthermore, compared to a configuration in which the target user inputs a user name into the printer 10, the operation performed by the target user can be simplified. Therefore, the convenience of the target user is improved.

[0085] Furthermore, when an authenticator 50A that supports user-nameless authentication is connected, the printer 10 receives the user names "aaa_company" and "aaa_home" from the authenticator 50A (T136 in FIG. 5), and when an authenticator 50B that does not support user-nameless authentication is connected, the printer 10 receives the user names "aaa_company" and "aaa_home" from the server 200 (T722 in FIG. 10). In this way, the printer 10 can execute appropriate processing depending on whether or not the authenticator supports user-nameless authentication.

[0086] In this embodiment, the server 200 stores the job ID and the print data in association with the user name. Therefore, in order for the target user to download the print data desired by the server 200, FIDO authentication must be performed using the user name associated with the print data. According to the above configuration, the target user can select the user name corresponding to the print data that the target user wishes to download. Therefore, the target user can cause the printer 10 to execute printing using the desired print data. This improves the convenience of the target user.

[0087] (Correspondence) The printer 10 is an example of a "communication device." The fingerprint information is an example of "biometric authentication information." The user ID is an example of "user identification information." The key ID is an example of "key information." The non-volatile memory 60A of the authentication device 50A is an example of a "first memory." The user name selection screen is an example of a "first selection screen." The user name "aaa_company" is an example of a "specific user name." The one-time pass is an example of "verification information." The private key PRK1 is an example of a "specific private key." The user ID "user1" is an example of "specific user identification information." The public key PUK1 is an example of a "specific public key." The USB I / F 18 is an example of an "interface." The authentication device 50A that supports user nameless authentication is an example of a "first type of authenticator." The authentication device 50B that does not support user nameless authentication is an example of a "second type of authenticator." The support information is an example of "type information." The job ID is an example of "print data identification information." The job selection screen is an example of a "second selection screen." The job IDs "job1" and "jpb3" are examples of "specific print data identification information." The print data PD1 and PD3 are examples of "specific print data." The non-volatile memory 36 of the printer 10 is an example of a "second memory." The installation information 42 is an example of a "setting value." "PUBLIC" in the installation information 42 is an example of a "first value." "OFFICE" in the installation information 42 is an example of a "second value." "HOME" in the installation information 42 is an example of a "third value."

[0088] T136 in Fig. 5 and T722 in Fig. 10 are examples of processing executed by an "acquisition unit." T138 in Fig. 5 and T724 in Fig. 10 are examples of processing executed by a "first display control unit." T146 in Fig. 5 and T748 in Fig. 10 are examples of processing executed by a "signature information transmission unit."

[0089] Although specific examples of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and alterations of the specific examples exemplified above. Modifications of the above-mentioned embodiments are listed below.

[0090] (First Modification) The "communication device" is not limited to a printer, but may be a mobile terminal such as a PC or a smartphone.

[0091] (Second Modification) When the mobile terminal is an example of a "communication device" and supports user nameless authentication, fingerprint information 62A and information corresponding to authentication table 64A may be stored in the memory of the mobile terminal. Also, when the mobile terminal does not support user nameless authentication, fingerprint information 62B and information corresponding to authentication table 64B may be stored in the memory of the mobile terminal. In this modification, the memory of the mobile terminal is an example of a "first memory." Also, in this modification, the user performs a fingerprint authentication operation on the mobile terminal.

[0092] (Third Modification) The "user identification information" is not limited to a user ID, and may be a user name.

[0093] 10 may include the RPID "URL1" instead of the serial number of the authentication device. In this modification, the server 200 transmits to the printer 10 two or more user names stored in the management table 242 in association with the RPID "URL1".

[0094] (Fifth Modification) In the above embodiment, the printer 10 may be configured to be able to execute a process corresponding to the authentication device 50A that supports user-nameless authentication, and a process corresponding to the authentication device 50B that does not support user-nameless authentication. Specifically, the printer 10 acquires a user name from the authentication device when the authentication device connected to the printer 10 supports user-nameless authentication, and acquires a user name from the server 200 when the authentication device connected to the printer 10 does not support user-nameless authentication. In a modification, the printer 10 may be configured to be able to execute only a process corresponding to the authentication device 50A that supports user-nameless authentication, or may be configured to be able to execute only a process corresponding to the authentication device 50B that does not support user-nameless authentication.

[0095] (Sixth Modification) The printer 10 may be configured to be capable of executing only one or two of the first logout process, the second logout process, and the third logout process. In another modification, the printer 10 may be configured to transmit a logout request to the server 200 only when the authenticators 50A and 50B are removed from the printer 10.

[0096] (Seventh Modification) In case C of FIG. 6, the printer 10 may execute the processes from T272 onwards even if the authentication device 50A is not removed from the printer 10 after printing has failed. That is, the printer 10 may execute the first logout process even if the logout operation is not accepted. In this modification, T270 can be omitted. In case D of FIG. 7, the printer 10 may execute the processes from T372 onwards even if the authentication device 50A is not removed from the printer 10 after printing has failed. That is, the printer 10 may execute the second logout process even if the logout operation is not accepted. In this modification, T370 can be omitted.

[0097] (Eighth Modification) The printer 10 may determine which of the first logout process, the second logout process, and the third logout process to execute, depending on the usage history of the printer 10. For example, the printer 10 may switch the content of the logout process to execute depending on the number of authentication devices connected to the printer 10. In another modification, the printer 10 may determine which of the first logout process, the second logout process, and the third logout process to execute, depending on a user operation after a printing failure.

[0098] (Ninth Modification) The printer 10 may stop printing if the authentication devices 50A, 50B are removed during printing.

[0099] (Tenth Modification) In case A of Figures 3 and 4, T28 to T32 may be executed after T34 to T40. Also in case B of Figures 5 and 6, T128 to T132 may be executed after T134 to T140.

[0100] (Eleventh Modification) In the above embodiment, the processes in FIGS. 3 to 11 are realized by software (for example, programs 40, 140, 240), but at least one of these processes may be realized by hardware such as a logic circuit.

[0101] In addition, the technical elements described in this specification or drawings exert technical utility 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 exemplified in this specification or drawings achieve multiple objectives simultaneously, and achieving one of those objectives itself has technical utility.

[0102] In the scope of the claims at the time of filing of this patent application, even if each claim is dependent on only some of the claims, it is not limited to the fact that each claim can be dependent on only those some of the claims. Each claim can also be dependent on other claims that are not dependent on it at the time of filing to the extent that there is no technical contradiction. In other words, the technology of each claim can be combined in various ways as follows: (Item 1) A communication device that operates according to a predetermined authentication scheme using a pair of keys, A display unit; an acquisition unit that acquires, in a specific state in which a plurality of pieces of user identification information and a plurality of pieces of key information corresponding to the plurality of pieces of user identification information are stored in a first memory in association with one piece of biometric authentication information, two or more user names corresponding to two or more pieces of user identification information among the plurality of pieces of user identification information; a first display control unit that causes the display unit to display a first selection screen for selecting one user name from the two or more acquired user names; a verification information receiving unit that receives verification information from the server in response to transmitting an authentication request to the server; a signature information acquisition unit that acquires signature information generated by encrypting the verification information using a specific private key when authentication of the target user using the one piece of biometric authentication information is successful, a specific user name is selected on the first selection screen, and the verification information is received from the server, the specific private key being a key corresponding to specific key information stored in the first memory in association with specific user identification information corresponding to the selected specific user name; a signature information transmission unit that transmits the selected specific user identification information and the generated signature information to the server, the server decrypting the signature information by using a specific public key that is associated with the specific user identification information and stored in the server; A communication device comprising: (Item 2) the communication device includes an interface to which an authenticator including the first memory is connected; the first memory stores the plurality of pieces of user identification information, the plurality of pieces of key information, and a plurality of user names corresponding to the plurality of pieces of user identification information, in association with the one piece of biometric authentication information; The communication device described in item 1, wherein the acquisition unit acquires two or more user names from the authentication device when the communication device is in the specific state and the authentication device is connected to the interface, the two or more user names being stored in the first memory from the authentication device. (Item 3) the communication device includes an interface to which an authenticator including the first memory is connected; The communication device described in item 1, wherein the acquisition unit receives from the server the two or more user names stored in the server when the communication device is in the specific state and the authentication device is connected to the interface. (Item 4) the acquisition unit, in the specific state and in a state in which the authenticator is connected to the interface, receives the two or more user names from the server in response to transmitting a user name request to the server, the user name request including authenticator identification information that identifies the authenticator; The communication device described in item 3, wherein each of the two or more user identification information is user identification information stored in association with the authentication device identification information among the multiple user identification information stored in the server. (Item 5) the communication device includes an interface to which an authenticator including the first memory is connected; The first memory includes: When the authentication device is a first type authentication device, the authentication device stores the plurality of pieces of user identification information, the plurality of pieces of key information, and a plurality of user names corresponding to the plurality of pieces of user identification information, in association with the one piece of biometric authentication information; When the authentication device is a second type authentication device different from the first type authentication device, the authentication device stores the plurality of pieces of user identification information and the plurality of pieces of key information in association with the one piece of biometric authentication information, but does not store the plurality of user names; The communication device further comprises: a type information receiving unit that receives, when the authenticator is connected to the interface, type information from the authenticator indicating whether the authenticator is the first type authenticator or the second type authenticator; The acquisition unit is When the specific state is reached and the authenticator is connected to the interface, if the received type information indicates that the authenticator is the first type of authenticator, obtain from the authenticator the two or more user names among the plurality of user names stored in the first memory; The communication device described in item 1, wherein when the communication device is in the specific state and the authenticator is connected to the interface, the communication device receives from the server the two or more user names stored in the server when the received type information indicates that the authenticator is the second type of authenticator. (Item 6) The communication device includes a print execution unit, The communication device further comprises: a print identification information receiving unit that receives, in response to transmitting the signature information to the server, from the server, one or more pieces of print data identification information that are associated with the specific user name and stored in the server; a second display control unit that causes the display unit to display a second selection screen for selecting one piece of print data identification information from the one or more pieces of print data identification information that have been received; a print data request sending unit that sends a print data request including the specific print data identification information to the server when the specific print data identification information is selected on the second selection screen; a print data receiving unit for receiving specific print data corresponding to the specific print data identification information from the server; a print control unit that causes the print execution unit to execute printing using the received print data. 6. A communication device according to any one of items 1 to 5. (Item 7) the communication device comprises a second memory; the server transitions from a logout state to a login state when the verification information is obtained by decrypting the signature information using the specific public key; The communication device further comprises: a storage control unit configured to store the one or more pieces of print data identification information in the second memory when the one or more pieces of print data identification information are received from the server; a logout process execution unit that executes one of a first logout process, a second logout process, and a third logout process when the printing using the print data fails due to an error occurring in the communication device, In the first logout process, a logout request is transmitted to the server for requesting the server to transition from the logged-in state to the logged-out state, and the one or more pieces of data identification information are erased from the second memory; in the second logout process, the logout request is sent to the server, and the one or more pieces of data identification information are not deleted from the second memory; The communication device described in item 6, wherein in the third logout processing, when a logout operation is received from the target user before the error is resolved, the printing is resumed in response to the error being resolved, and after the printing is completed, the one or more pieces of data identification information are erased from the second memory. (Item 8) the second memory stores a setting value related to logout; The logout process execution unit, executes the first logout process when the setting value indicates a first value; executes the second logout process when the setting value indicates a second value; 8. The computer program according to item 7, further comprising: executing the third logout process when the setting value indicates a third value. (Item 9) The communication device described in any one of items 6 to 8, wherein the communication device has an interface to which an authentication device having the first memory is connected, and the printing control unit does not stop the printing execution even if the authentication device is removed from the interface while the printing using the print data is being executed. (Item 10) 1. A computer program for a communication device that operates according to a predetermined authentication scheme using a pair of keys, comprising: The communication device includes: A display unit is provided, The computer of the communication device is composed of the following parts: an acquisition unit that acquires, in a specific state in which a plurality of pieces of user identification information and a plurality of pieces of key information corresponding to the plurality of pieces of user identification information are stored in a first memory in association with one piece of biometric authentication information, two or more user names corresponding to two or more pieces of user identification information among the plurality of pieces of user identification information; a first display control unit that causes the display unit to display a first selection screen for selecting one user name from the two or more acquired user names; a verification information receiving unit that receives verification information from the server in response to transmitting an authentication request to the server; a signature information acquisition unit that acquires signature information generated by encrypting the verification information using a specific private key when authentication of the target user using the one piece of biometric authentication information is successful, a specific user name is selected on the first selection screen, and the verification information is received from the server, the specific private key being a key corresponding to specific key information stored in the first memory in association with specific user identification information corresponding to the selected specific user name; a signature information transmission unit that transmits the selected specific user identification information and the generated signature information to the server, the server decrypting the signature information by using a specific public key that is associated with the specific user identification information and stored in the server; A computer program that functions as a (Item 11) 1. A method performed by a communication device operating according to a predetermined authentication scheme utilizing a pair of keys, comprising: The communication device includes: A display unit is provided, The method comprises: an acquisition step of acquiring two or more user names corresponding to two or more user identification information among the plurality of pieces of user identification information in a specific state in which the plurality of pieces of user identification information and the plurality of pieces of key information corresponding to the plurality of pieces of user identification information are stored in a first memory in association with one piece of biometric authentication information; a first display control step of displaying on the display unit a first selection screen for selecting one user name from the two or more user names that have been acquired; a verification information receiving step of receiving verification information from the server in response to transmitting an authentication request to the server; a signature information acquisition step of acquiring signature information generated by encrypting the verification information using a specific private key when authentication of the target user using the one piece of biometric authentication information is successful, a specific user name is selected on the first selection screen, and the verification information is received from the server, the specific private key being a key corresponding to specific key information stored in the first memory in association with specific user identification information corresponding to the selected specific user name; a signature information transmitting step of transmitting the selected specific user identification information and the generated signature information to the server, the server decrypting the signature information by using a specific public key stored in the server in association with the specific user identification information; A method comprising: [Explanation of symbols]

[0103] 2: communication system, 6: Internet, 10: printer, 12: operation unit, 14: display unit, 16: print execution unit, 18: USB I / F, 20: communication I / F, 30: control unit, 32: CPU, 34: volatile memory, 36: non-volatile memory, 40: program, 42: installation information, 50A: authentication device, 50B: authentication device, 60A: non-volatile memory, 60B: non-volatile memory, 62A: fingerprint information, 62B: fingerprint information, 64 A: authentication table, 64B: authentication table, 100: PC, 112: operation unit, 114: display unit, 120: communication I / F, 130: control unit, 132: CPU, 134: volatile memory, 136: non-volatile memory, 140: OS program, 200: server, 220: communication I / F, 230: control unit, 232: CPU, 234: volatile memory, 236: non-volatile memory, 240: program, 242: management table

Claims

1. A communication device that operates according to a predetermined authentication scheme using a pair of keys, A display unit; an acquisition unit that acquires, in a specific state in which a plurality of pieces of user identification information and a plurality of pieces of key information corresponding to the plurality of pieces of user identification information are stored in a first memory in association with one piece of biometric authentication information, two or more user names corresponding to two or more pieces of user identification information among the plurality of pieces of user identification information; a first display control unit that causes a first selection screen for selecting one user name from the two or more acquired user names to be displayed on the display unit; a verification information receiving unit that receives verification information from the server in response to transmitting an authentication request to the server; a signature information acquisition unit that acquires signature information generated by encrypting the verification information using a specific private key when authentication of the target user using the one piece of biometric authentication information is successful, a specific user name is selected on the first selection screen, and the verification information is received from the server, the signature information acquisition unit being a key corresponding to specific key information stored in the first memory in association with specific user identification information corresponding to the selected specific user name; a signature information transmission unit that transmits the selected specific user identification information and the generated signature information to the server, the server decrypting the signature information by using a specific public key that is associated with the specific user identification information and stored in the server; A communication device comprising:

2. the communication device includes an interface to which an authenticator including the first memory is connected; the first memory stores the plurality of pieces of user identification information, the plurality of pieces of key information, and a plurality of user names corresponding to the plurality of pieces of user identification information, in association with the one piece of biometric authentication information; 2. The communication device according to claim 1, wherein the acquisition unit acquires, from the authentication device in the specific state and in a state in which the authentication device is connected to the interface, the two or more user names among the plurality of user names stored in the first memory.

3. the communication device includes an interface to which an authenticator including the first memory is connected; 2 . The communication device according to claim 1 , wherein the acquisition unit receives, from the server, the two or more user names stored in the server when the communication device is in the specific state and the authentication device is connected to the interface.

4. the acquisition unit, in a state in which the authentication device is in the specific state and the authentication device is connected to the interface, receives the two or more user names from the server in response to transmitting a user name request to the server, the user name request including authentication device identification information that identifies the authentication device; The communication device according to claim 3 , wherein each of the two or more pieces of user identification information is user identification information stored in association with the authentication device identification information among the plurality of pieces of user identification information stored in the server.

5. the communication device includes an interface to which an authenticator including the first memory is connected; The first memory includes: When the authentication device is a first type authentication device, the plurality of pieces of user identification information, the plurality of pieces of key information, and a plurality of user names corresponding to the plurality of pieces of user identification information are stored in association with the one piece of biometric authentication information, When the authentication device is a second type authentication device different from the first type authentication device, the plurality of pieces of user identification information and the plurality of pieces of key information are stored in association with the one piece of biometric authentication information, but the plurality of user names are not stored; The communication device further comprises: a type information receiving unit that receives, when the authenticator is connected to the interface, type information from the authenticator indicating whether the authenticator is the first type authenticator or the second type authenticator; The acquisition unit is When the specific state is reached and the authenticator is connected to the interface, if the received type information indicates that the authenticator is the first type of authenticator, obtain from the authenticator the two or more user names among the plurality of user names stored in the first memory; 2. The communication device according to claim 1, wherein when the specific state is present and the authenticator is connected to the interface, the communication device receives from the server the two or more user names stored in the server when the received type information indicates that the authenticator is the second type of authenticator.

6. The communication device includes a print execution unit, The communication device further comprises: a print identification information receiving unit that receives, in response to transmitting the signature information to the server, from the server, one or more pieces of print data identification information that are associated with the specific user name and stored in the server; a second display control unit that causes the display unit to display a second selection screen for selecting one piece of print data identification information from the one or more pieces of print data identification information that have been received; a print data request sending unit that sends a print data request including the specific print data identification information to the server when the specific print data identification information is selected on the second selection screen; a print data receiving unit for receiving specific print data corresponding to the specific print data identification information from the server; a print control unit that causes the print execution unit to execute printing using the received print data. The communication device according to claim 1 .

7. the communication device comprises a second memory; the server transitions from a logout state to a login state when the verification information is obtained by decrypting the signature information using the specific public key; The communication device further comprises: a storage control unit configured to store the one or more pieces of print data identification information in the second memory when the one or more pieces of print data identification information are received from the server; a logout process execution unit that executes one of a first logout process, a second logout process, and a third logout process when the printing using the print data fails due to an error occurring in the communication device, In the first logout process, a logout request is transmitted to the server for requesting the server to transition from the logged-in state to the logged-out state, and the one or more pieces of data identification information are erased from the second memory; in the second logout process, the logout request is sent to the server, and the one or more pieces of data identification information are not deleted from the second memory; The communication device of claim 6, wherein in the third logout process, when a logout operation is received from the target user before the error is resolved, the printing is resumed in response to the error being resolved, and after the printing is completed, the one or more pieces of data identification information are erased from the second memory.

8. the second memory stores a setting value related to logout; The logout process execution unit, executes the first logout process when the setting value indicates a first value; executes the second logout process when the setting value indicates a second value; The computer program product according to claim 7 , further comprising: executing the third logout process when the setting value indicates a third value.

9. the communication device includes an interface to which an authenticator including the first memory is connected; The communication device according to claim 6 , wherein the print control unit does not stop the execution of the printing even if the authentication device is detached from the interface while the printing using the print data is being executed.

10. 1. A computer program for a communication device that operates according to a predetermined authentication scheme using a pair of keys, comprising: The communication device includes: A display unit is provided, The computer of the communication device is composed of the following parts: an acquisition unit that acquires, in a specific state in which a plurality of pieces of user identification information and a plurality of pieces of key information corresponding to the plurality of pieces of user identification information are stored in a first memory in association with one piece of biometric authentication information, two or more user names corresponding to two or more pieces of user identification information among the plurality of pieces of user identification information; a first display control unit that causes a first selection screen for selecting one user name from the two or more acquired user names to be displayed on the display unit; a verification information receiving unit that receives verification information from the server in response to transmitting an authentication request to the server; a signature information acquisition unit that acquires signature information generated by encrypting the verification information using a specific private key when authentication of the target user using the one piece of biometric authentication information is successful, a specific user name is selected on the first selection screen, and the verification information is received from the server, the signature information acquisition unit being a key corresponding to specific key information stored in the first memory in association with specific user identification information corresponding to the selected specific user name; a signature information transmission unit that transmits the selected specific user identification information and the generated signature information to the server, the server decrypting the signature information by using a specific public key that is associated with the specific user identification information and stored in the server; A computer program that functions as a

11. 1. A method performed by a communication device operating according to a predetermined authentication scheme utilizing a pair of keys, comprising: The communication device includes: A display unit is provided, The method comprises: an acquisition step of acquiring two or more user names corresponding to two or more user identification information among the plurality of pieces of user identification information in a specific state in which the plurality of pieces of user identification information and the plurality of pieces of key information corresponding to the plurality of pieces of user identification information are stored in a first memory in association with one piece of biometric authentication information; a first display control step of causing the display unit to display a first selection screen for selecting one user name from the two or more acquired user names; a verification information receiving step of receiving verification information from the server in response to transmitting an authentication request to the server; a signature information acquisition step of acquiring signature information generated by encrypting the verification information using a specific private key when authentication of the target user using the one piece of biometric authentication information is successful, a specific user name is selected on the first selection screen, and the verification information is received from the server, the signature information acquisition step being a step corresponding to specific key information stored in the first memory in association with specific user identification information corresponding to the selected specific user name; a signature information transmitting step of transmitting the selected specific user identification information and the generated signature information to the server, the server decrypting the signature information by using a specific public key stored in the server in association with the specific user identification information; A method comprising:

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