JP2004206620A - Printing system and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrict positions which can be used by a printer 30. <P>SOLUTION: A service provider 15 determines whether or not a person who requests generation of a public key is the person having legitimate authority regarding generation of the public key. When the service provider 15 determines the person to have the legitimate authority, the printer 30 generates and stores the public key by public key cryptography by using a path phrase at least including printer positional information at the point of time. Then, the printer 30 transmits the public key to a printing client 20 according to a request from the printing client 20. When the printing client 20 transmits printing data D05 to the printer 30, encrypts the printing data D05 by using the acquired public key and transmits it as data D10 for printing transmission. The printer 30 receiving the data D10 for printing transmission generates a private key by the public key cryptography by using the path phrase at least including the printer positional information at the point of time. Then, the received data D10 for printing transmission is decoded by using the private key. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a printing system and a control method thereof, and more particularly, to a printing system and a control method thereof in which a place where a printer can perform normal printing is limited.
[0002]
[Prior art]
In recent years, as a business model using a printer, a form in which a printer maker rents a printer to a user free of charge and the user pays a usage fee to the printer maker for the number of prints using the printer has been attracting attention. . In such a business model, besides charging based on the number of prints, charging based on the usage period, charging based on the amount of ink used, and the like can be considered.
[0003]
[Patent Document 1]
JP-A-11-331144
[0004]
[Problems to be solved by the invention]
However, in such a business model, if a user rents a printer lent from a printer maker without permission or rents it to another person, the printer maker can charge for the use of the printer. Will be gone. For this reason, the printer manufacturer wants to limit the place where the lent printer can be used, that is, the place where normal printing can be performed, to the place of the lent user.
[0005]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a printing system and a control method thereof, in which a printer can perform normal printing only in a place that has been authenticated in advance.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, a printing system according to the present invention is a printing system including a printing client, a printer that performs printing based on a request from the printing client, and at least a service provider connected to the printing client. The printer includes printer position information obtaining means for obtaining printer position information for specifying a location where the printer is installed, and the service provider has a right to generate a public key. A determination unit that determines whether or not the printer has the right to perform the determination of the service location. Printer position information is acquired from the information acquisition means, and this is referred to as first printer position information Rutotomoni, using a passphrase comprising at least the first printer position information to generate a public key, the public key generation means, and further, it is characterized.
[0007]
In this case, the printer may further include a first public key storage unit that stores the public key generated by the public key generation unit.
[0008]
In this case, the printer further includes a public key transmitting unit that reads a public key from the public key first storage unit and transmits the public key to the print client, wherein the print client receives the public key received from the printer. May be further provided.
[0009]
In this case, the print client reads out a public key from the print data generating unit and the public key second storage unit, which generates print data for printing by the printer, and converts the print data with the public key. Print data transmitting means for transmitting the encrypted print data to the printer, wherein the printer further receives the print data encrypted with the public key. Receiving means, printer position information acquiring means for acquiring printer position information from the printer position information acquiring means when the print data is received, and using the acquired printer position information as second printer position information; Secret key generation means for generating a secret key using a passphrase including at least position information, and the print data receiving means using the secret key It decodes the received the print data, and decoding means, may be provided with a.
[0010]
In this case, the print client further includes an authentication information requesting unit for requesting authentication information from the operator, and the determination unit of the service provider acquires the input authentication information and registers the obtained authentication information. It may be determined whether or not the authentication information matches the existing authentication information. If the two match, the operator may be determined to be a person who has valid authority.
[0011]
Further, when the public key generation means of the printer generates a public key, even if a secret key is generated, the secret key may be destroyed.
[0012]
Further, the printer executes printing based on the print data when the print data can be decrypted using the secret key, and executes the printing based on the print data when the print data cannot be decrypted using the secret key. Further, a selective print execution unit that does not execute printing based on the print data may be further provided.
[0013]
Note that the present invention can also be realized as a control method for controlling a printing system. Further, it can be realized as a program for controlling the printing system and a recording medium on which the program is recorded.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
In the printing system according to the present embodiment, the service provider performs authentication for generating a public key, and if the authentications match, the printer sends a passphrase including at least printer location information indicating the location where the printer is installed. A public key is generated using the public key, and this is held. Then, the printer provides the public key to the print client as needed. On the other hand, if the authentications at the service provider do not match, the printer does not generate a public key.
[0015]
When the print client transmits the print data to the printer, the print client encrypts the print data using the obtained public key and transmits the encrypted print data as print transmission data. When the printer that has received the print transmission data generates a secret key using the passphrase including at least the printer position information at the time of reception at the time of reception, the print transmission data can be decrypted with the secret key. The printing is executed only for the printer. This will be described in more detail below.
[0016]
First, a configuration of a printing system according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram illustrating a hardware configuration of a printing system according to the present embodiment.
[0017]
As shown in FIG. 1, the printing system according to the present embodiment includes a print client 20 and a printer 30 connected via a printer cable 10. That is, the printer 30 is locally connected to the print client 20. However, the print client 20 and the printer 30 may be connected by a network using wireless or Ethernet (registered trademark). In this case, a plurality of print clients 20 may be connected to one printer 30.
[0018]
Further, the print client 20 is connected to a network NT such as the Internet or Ethernet (registered trademark). The network NT is connected to a service provider 15 that determines whether or not a person who has requested generation of a public key is a person who has valid authority for generating a public key.
[0019]
The print client 20 is configured by, for example, various computers called host computers and personal computers. In the present embodiment, in particular, the print client 20 generates print transmission data obtained by encrypting print data with a public key, and transmits the print transmission data to the printer 30 via the printer cable 10. The print client 20 is not limited to a computer, but may be, for example, a digital camera that needs to print a captured image, or a content server that stores print image data as content.
[0020]
Further, in the present embodiment, the service provider 15 authenticates whether the person who has requested the generation of the public key is a person having the right authority, and it is recognized that the service provider 15 has the right authority. Only in this case, the printer 30 generates a public key by public key cryptography. The public key generated by the printer 30 is held by the printer 30, transmitted to the print client 20 in response to a request from a valid print client 20, and stored therein.
[0021]
When transmitting the print data to the printer 30, the print client 20 encrypts the print data with the public key and transmits the encrypted print data to the printer 30 as print transmission data. The printer 30 receives the print transmission data from the print client 20, and decrypts the print transmission data with a secret key generated using a passphrase including at least the printer position information at that time. If the print transmission data can be decrypted, printing based on the print transmission data is performed. If the print transmission data cannot be decrypted, printing based on the print transmission data is performed. Absent.
[0022]
Further, in the present embodiment, the printer 30 is configured so that a normal print result cannot be obtained with print data not encrypted with the public key. That is, the unencrypted print data is handled by the printer 30 as print transmission data that cannot be decrypted using the secret key.
[0023]
FIG. 2 is a block diagram for explaining the internal configuration of the printer 30. As shown in FIG. 2, the printer 30 includes a CPU (Central Processing Unit) 40, a RAM (Random Access Memory) 42, a ROM (Read Only Memory) 44, and an EEPROM (Electrically Erasable Programmable ROM) 45. These are connected to each other via an internal bus 46. Further, a communication interface 48 is connected to the internal bus 46, and the printer 30 is connected to the printer cable 10 via the communication interface 48. Further, an interface 50 is connected to the internal bus 46, and a print engine 52 is connected to the interface 50. In the present embodiment, the EEPROM 45 functions as a rewritable nonvolatile storage device.
[0024]
Further, a position detection unit 54 is connected to the internal bus 46. The position detecting section 54 has a function of specifying the position where the printer 30 is installed. In the present embodiment, the printer 30 is configured by, for example, a GPS (global positioning system), and the latitude, longitude, and altitude of the position where the printer 30 is installed can be specified. It is said that the GPS accuracy at the present time is about ± 10 m in latitude, longitude and altitude.
[0025]
However, the position detecting unit 54 is not limited to the configuration using the GPS, and may specify the position of the printer 30 using a mobile communication technology such as a PHS (Personal Handyphone System). Further, when GPS and PHS are used in combination and a GPS radio wave cannot be normally received indoors, the position may be specified based on the PHS radio wave.
[0026]
Further, a hard disk 58 is connected to the internal bus 46 via an interface 56. In the present embodiment, the hard disk 58 functions as a rewritable nonvolatile storage device.
[0027]
FIG. 3 is a block diagram for explaining the internal configuration of the print client 20. As shown in FIG. 3, the print client 20 according to the present embodiment includes a computer main body 60 and a display 62.
[0028]
The computer main body 60 includes a CPU 64, a RAM 66, and a ROM 68, which are connected to each other via an internal bus 70. Further, communication interfaces 72 and 73 are connected to the internal bus 70, and the print client 20 is connected to the above-described printer cable 10 via the communication interface 72. The print client 20 is connected to the network NT via 73.
[0029]
Further, an interface 74 is connected to the internal bus 70, and a hard disk 76 as a mass storage device is connected to the interface 74. In the present embodiment, the hard disk 76 functions as a rewritable nonvolatile storage device. An interface 78 is connected to the internal bus 70, and the above-described display 62 is connected to the internal bus 70 via a cable 80 extending from the interface 78.
[0030]
FIG. 4 is a block diagram for explaining the internal configuration of the service provider 15. As shown in FIG. 4, the service provider 15 according to the present embodiment includes a computer main body 100 and a display 102.
[0031]
The computer main body 100 includes a CPU 104, a RAM 106, and a ROM 108, which are connected to each other via an internal bus 110. A communication interface 112 is connected to the internal bus 110, and the service provider 15 is connected to the network NT via the communication interface 72.
[0032]
Further, an interface 114 is connected to the internal bus 110, and a hard disk 116 as a mass storage device is connected to the interface 114. In the present embodiment, the hard disk 116 functions as a rewritable nonvolatile storage device. Further, an interface 118 is connected to the internal bus 110, and the above-described display 102 is connected to the internal bus 110 via a cable 120 extending from the interface 118.
[0033]
Next, in the printing system according to the present embodiment, processing when the print client 20 performs printing with the printer 30 will be schematically described.
[0034]
In the present embodiment, the service provider 15 authenticates whether or not the user has a legitimate authority to request generation of a public key. In the present embodiment, the print client 20 allows the operator to input the public key generation authentication information, transmits the public key generation authentication information to the service provider 15, and determines whether or not the user has the right authority. I do. In the present embodiment, the public key generation authentication information is composed of a combination of an ID and a password.
[0035]
If the authentications match, the service provider 15 sends the print client 20 authentication result information indicating that the authentications match. The print client 20 transmits to the printer 30 a public key generation request and authentication result information indicating that the authentications match. The printer 30 having received these generates a public key by a public key cryptography using a passphrase including at least the printer position information at that time. Then, the printer 30 stores the generated public key in the EEPROM 45.
[0036]
When the print client 20 having valid authority requests the public key, the printer 30 reads the public key from the EEPROM 45 and transmits the read public key to the print client 20 via the printer cable 10.
[0037]
The print client 20 stores the received public key in the hard disk 74. Next, as shown in FIG. 5, the user of the print client 20 creates print data D05, which is data to be printed, and designates the printer 30 to the print client 20 to instruct printing.
[0038]
The print client 20 encrypts the print data D05 using the public key of the printer 30, and generates print transmission data D10. Here, the print data D05 indicates the original print data necessary for performing printing by driving the print engine 52 by the printer 30. The print transmission data D10 may include data other than the print data D05 shown in FIG.
[0039]
The printer 30 that has received the print transmission data D10 temporarily stores the received print transmission data D10 in the RAM 42 as shown in FIG. Then, the printer 30 decrypts the encrypted print transmission data D10 using the secret key. That is, the printer 30 generates a secret key by public key cryptography using a passphrase including at least the printer position information at that time. In this manner, by generating a secret key every time the print transmission data D10 is to be decrypted, if the installation location of the printer 30 is moved, the secret key is generated using the public key generated before the movement. The converted print transmission data cannot be decrypted by the moved printer 30.
[0040]
Subsequently, the printer 30 determines whether the print transmission data D10 has been successfully decrypted. If the print transmission data D10 has been successfully decoded, printing is performed based on the print data D05 obtained by decoding the print transmission data D10, and if not, no printing is performed.
[0041]
Next, the contents of the above-described processing will be described in detail with reference to a flowchart. First, a process for generating a public key will be described.
[0042]
FIG. 6 is a flowchart illustrating a public key generation request process performed by the print client 20. The public key generation request processing is realized by the CPU 64 reading and executing a public key generation request program stored in the ROM 68 or the hard disk 76 of the print client 20. Further, in the present embodiment, the public key generation request processing is such that an operator (for example, a person who maintains the maker of the printer 30) operates the print client 20 to execute the public key generation request processing. Is started and executed.
[0043]
As shown in FIG. 6, when the public key generation request processing is executed, the print client 20 first requests the operator to input the public key generation authentication information (step S10). In the present embodiment, the operator inputs an ID and a password as public key generation authentication information from a keyboard or the like of the print client 20.
[0044]
Next, the print client 20 determines whether the public key generation authentication information has been input (step S12). If the public key generation authentication information has not been input (step S12: No), the process of step S12 is repeated to wait.
[0045]
On the other hand, when the public key generation authentication information is input (step S12: Yes), the print client 20 establishes a connection with the service provider 15 via the network NT (step S14). For data transmission / reception, for example, contents are encrypted by SSL or the like, and then exchanged. The same applies to the service provider 15 of the other party. Then, the print client 20 transmits the public key generation authentication information to the service provider 15 (Step S16).
[0046]
Next, since the print client 20 receives the authentication result information from the service provider 15, the print client 20 determines whether the authentication result information indicates that the public key generation authentication information matches (step S18). If the authentication result information indicates that the public key generation authentication information matches (step S18: Yes), the print client 20 transmits a public key generation request to the printer 30 (step S20). Subsequently, the print client 20 transmits authentication result information indicating that the public key generation authentication information matches the printer 30 (step S22).
[0047]
Next, the print client 20 disconnects the connection with the service provider 15 (step S24). On the other hand, if it is determined in step S18 that the authentication result information that the public key generation authentication information does not match is received (step S18: No), the process jumps to step S24 to establish a connection with the service provider 15. Disconnect.
[0048]
Thereby, the public key generation request processing according to the present embodiment ends.
[0049]
FIG. 7 is a flowchart illustrating an authentication process performed by the service provider 15. This authentication processing is realized by the CPU 104 reading and executing an authentication program stored in the ROM 108 or the hard disk 116 of the service provider 15. In the present embodiment, the authentication process is a process that is constantly executed at regular time intervals.
[0050]
As shown in FIG. 7, in the public key generation processing, the service provider 15 is waiting for a connection from the print client 20 (step S50). Then, when connected to the print client 20, the service provider 15 determines whether public key generation authentication information has been received from the print client 20 (step S52). If the public key generation authentication information has not been received (step S52: No), the process of step S52 is repeated to wait.
[0051]
On the other hand, if the public key generation authentication information has been received (step S52: Yes), the service provider 15 determines whether the public key generation authentication information matches information registered in advance (step S54). ). As described above, in the present embodiment, the public key generation authentication information is composed of an ID and a password, so that the ID and the password match the ID and the password registered in the hard disk 116 in advance. Judge whether or not.
[0052]
If it is determined that the public key generation authentication information does not match (step S54: No), authentication result information indicating that the public key generation authentication information does not match is transmitted to the print client 20 (step S56). Then, the connection with the print client 20 is terminated (step S60).
[0053]
On the other hand, when it is determined in step S54 that the public key generation authentication information matches (step S54: Yes), authentication result information indicating that the public key generation authentication information matches is transmitted to the print client 20. (Step S58). Then, the connection with the print client 20 is terminated (step S60), and the steps from step S50 are repeated.
[0054]
Next, a public key generation process executed by the printer 30 in response to a public key generation request process of the print client 20 will be described with reference to FIG. FIG. 8 is a flowchart illustrating a public key generation process performed by the printer 30. This public key generation process is realized by the CPU 40 reading and executing a public key generation program stored in the ROM 44 or the hard disk 58 of the printer 30. In the present embodiment, the public key generation process is a process that is constantly executed at a fixed time interval.
[0055]
As shown in FIG. 8, the printer 30 determines whether a public key generation request has been received from the print client 20 (step S80). If the public key generation request has not been received (step S80: No), the process of step S80 is repeated and the process stands by.
[0056]
On the other hand, when the public key generation request has been received (step S80: Yes), the printer 30 determines whether or not authentication result information indicating that the public key generation authentication information matches from the print client 20 has been received (step S80). Step S82). If the authentication result information has not been received (step S82: No), the process of step S82 is repeated to wait.
[0057]
On the other hand, if the authentication result information indicating that the public key generation authentication information matches (step S82: Yes), device-specific information is acquired (step S84). Here, the device-specific information is identification information uniquely assigned to the printer 30, and includes, for example, a manufacturing serial number and a MAC address of the printer 30.
[0058]
Next, the printer 30 acquires the printer position information at that time from the position detection unit 54 (Step S86). Subsequently, the printer 30 generates a passphrase (Step S88). Although various passphrase creation methods are conceivable, in the present embodiment, the passphrase is created simply by connecting the printer position information to the device-specific information. Note that the passphrase may include data other than the device-specific information and the printer position information.
[0059]
Next, the printer 30 generates a public key by public key cryptography using the passphrase generated in step S88 (step S90). Subsequently, the printer 30 stores the generated public key in the EEPROM 45 (step S92). FIG. 9 is a diagram showing a configuration of the public key storage unit EP10 formed in a partial area of the EEPROM 45. As shown in FIG. 9, the generated public key is stored and held in the public key storage unit EP10. If a private key is also generated when a public key is generated, the private key is discarded without being stored.
[0060]
After step S92, the process returns to step S50. Thus, the public key generation processing according to the present embodiment ends.
[0061]
Next, processing of the print client 20 and the printer 30 when the print client 20 acquires the public key will be described.
[0062]
FIG. 10 is a flowchart illustrating a public key request process performed by the print client 20. This public key request process is a process realized by the CPU 64 reading and executing a public key request program stored in the ROM 68 or the hard disk 76 of the print client. In the present embodiment, the public key request process is started and executed when the user inputs an instruction to the print client 20 to start a process for requesting a public key.
[0063]
As shown in FIG. 10, in the public key request process, first, the print client 20 establishes a connection with the printer 30 (step S100). Subsequently, the print client 20 transmits the authentication information to the printer 30 (Step S102). In the present embodiment, a combination of a print client ID for specifying a print client and a password is used as the authentication information. Therefore, the print client 20 transmits the print client ID and the password to the printer 30.
[0064]
Subsequently, the print client 20 receives the authentication result indicating whether or not the authentication has been accepted from the printer 30, and determines whether or not the printer 30 has been authenticated based on the authentication result (step S104). If the authentication has not been approved (step S104: No), the above steps from step S102 are repeated.
[0065]
On the other hand, if the authentication is approved (step S104: Yes), the print client 20 transmits a public key acquisition request to the printer 30 (step S106). Then, it is determined whether a public key has been received from the printer 30 (step S108). If the public key has not been received from the printer 30 (step S108: No), this step S108 is repeated to wait.
[0066]
On the other hand, when the public key has been received from the printer 30 (step S108: Yes), the public key is stored (step S110). In the present embodiment, the print client 20 has a public key table TB10 provided on the hard disk 76, and the acquired public key is stored and held in the public key table TB10.
[0067]
FIG. 11 is a diagram showing an example of the configuration of the public key table TB10. As shown in FIG. 11, the public key table TB10 includes an item TD10 for storing information for specifying a printer, and an item TD11 for storing the obtained public key in association with the printer. As described above, the public key table TB10 can hold public keys for a plurality of printers for each printer. In addition, by storing the public key in the public key table TB10 of the hard disk 78 in this manner, even if the power of the print client 20 is turned off and then turned on again, the public key obtained before that is directly stored in the hard disk 78. And can be used by reading them out.
[0068]
Next, as shown in FIG. 10, the print client 20 disconnects the connection with the printer 30 (step S112). Thus, the public key request process shown in FIG. 10 ends.
[0069]
Next, a public key transmission process executed by the printer 30 in response to the public key request process of the print client 20 will be described with reference to FIG. FIG. 12 is a flowchart illustrating a public key transmission process performed by the printer 30. This public key transmission processing is realized by the CPU 40 reading and executing a public key transmission program stored in the ROM 44 or the hard disk 58 of the printer. In the present embodiment, this public key transmission process is a process that is constantly executed at fixed time intervals. This public key transmission process is a process corresponding to the above-described public key request process.
[0070]
As shown in FIG. 12, the printer 30 is waiting for a connection from the print client 20, and establishes a connection with the print client 20 when a connection is requested from the print client 20 (step S120). This corresponds to step S100 on the print client 20 side described above. Subsequently, the printer 30 determines whether authentication information has been received from the print client 20 (step S122). If the authentication information has not been received (step S122: No), the process of step S122 is repeated to wait.
[0071]
On the other hand, when the authentication information has been received from the print client 20 (step S122: Yes), it is determined whether the authentication information matches the authentication information registered in the printer 30 in advance (step S124). Specifically, as described above, since the print client ID and the password are transmitted as authentication information from the print client 20, the print client ID and the password are registered with the print client ID registered in the printer 30 in advance. Determine if it matches the password.
[0072]
If the authentication information does not match (step S124: No), the printer 30 transmits an authentication result indicating that the authentication has not been accepted to the print client 20 (step S126). The connection with the client 20 is terminated (step S136). On the other hand, if the authentications match (step S124: Yes), the printer 30 transmits an authentication result indicating that the authentication has been accepted to the print client 20 (step S128).
[0073]
Next, the printer 30 determines whether a public key acquisition request has been received from the print client 20 (step S130). If the public key acquisition request has not been received (step S130: No), the process of step S130 is repeated to wait.
[0074]
If a public key acquisition request has been received (step S130: Yes), the printer 30 reads and acquires a public key from the public key storage unit EP10 of the EEPROM 45 (step S132). Subsequently, the printer 30 transmits the obtained public key to the print client 20 (Step S134). Then, the connection with the print client 20 is terminated (step S136), and the process returns to step S120.
[0075]
Next, the processing of the print client 20 and the printer 30 when transmitting the print request to the printer 30 when the print client 20 wants to perform printing will be described in detail.
[0076]
FIG. 13 is a flowchart illustrating a print request process executed by the print client 20. This print request processing is realized by the CPU 64 reading and executing a print request program stored in the ROM 68 or the hard disk 76 of the print client. In the present embodiment, the print request processing is started and executed when the user inputs a print instruction to the print client.
[0077]
As shown in FIG. 13, the print client 20 creates print data D05 based on a print request from the user (step S200). The print data D05 is data necessary for actually performing printing when the printer 30 is a normal printer.
[0078]
Next, the print client 20 reads the public key of the printer 30 from the public key table TB10 (Step S202). Subsequently, the print client 20 encrypts the print data D05 using the public key of the printer 30, and generates print transmission data D10 (step S204). The print transmission data D10 may include data other than the print data.
[0079]
Next, the print client 20 establishes a connection with the printer 30 (Step S206). The establishment of the connection with the printer 30 is not a necessary process depending on the connection specification between the print client 20 and the printer 30. Subsequently, the print client 20 transmits the encrypted print transmission data D10 to the printer 30 (Step S208).
[0080]
Next, the print client 20 determines whether or not print result information has been received from the printer 30 (step S210). If the print result information has not been received (step S210: No), the process of step S210 is repeated to wait. On the other hand, if the print result information has been received (step S210: Yes), it is determined whether the print result information is a print completion notification (step S212).
[0081]
If the print result information is a print completion notification (step S212: Yes), it means that the printing has been normally completed by the printer 30, and the user is notified that the printing has been completed by the printer 30. (Step S214). On the other hand, if the received print result information is not a print completion notification (step S212: No), it is determined whether or not the print result information is a decipherable notification (step S216).
[0082]
If the print result information is a non-decipherable notification (step S216: Yes), the user is notified that printing was not performed because the print transmission data D10 could not be decoded by the printer 30 (step S218). ). On the other hand, if the print result information is not the incomprehensible notification (step S216: No), it is considered to be some other error, and the user is notified according to the type of the error (step S220).
[0083]
After the notification of step S214, step S218, and step S220, the print client 20 disconnects the connection with the printer 30 (step S222). Thus, the print request processing in the print client 20 ends.
[0084]
Next, a print execution process executed by the printer 30 in response to a print request process of the print client 20 will be described with reference to FIG. FIG. 14 is a flowchart illustrating a print execution process performed by the printer 30. The print execution process is realized by the CPU 40 reading and executing a print execution program stored in the ROM 44 or the hard disk 58 of the printer 30. In the present embodiment, the print execution process is a process that is constantly executed at fixed time intervals.
[0085]
As shown in FIG. 14, the printer 30 is waiting for a connection from the print client 20, and when a connection is requested from the print client 20, the printer 30 connects to the print client 20 via the printer cable 10. Is established (step S250). This process is not always necessary depending on the connection specifications between the print client 20 and the printer 30. After the connection with the print client 20 is established, the printer 30 determines whether or not the print transmission data D10 has been received (step S252). If no print transmission data D10 has been received (step S252: No), the process of step S252 is repeated to wait.
[0086]
On the other hand, when the print transmission data D10 has been received (step S252: Yes), the printer 30 acquires its own device-specific information (step S254). Subsequently, the printer 30 acquires the printer position information of the printer 30 at that time from the position detection unit 54 (Step S256). The reason that the printer position information is acquired from the position detection unit 54 each time is that the position of the printer 30 when the private key is generated is different from the position of the printer 30 when the public key is generated. In this case, printing is not performed by the printer 30.
[0087]
Next, the printer 30 creates a passphrase based on the device-specific information and the printer position information (step S258). This passphrase creation method needs to be the same method as in step S88 in the above-described public key generation processing. This is because, if the passphrases are different, a secret key that can decrypt the print transmission data encrypted with the public key generated by the printer 30 cannot be generated.
[0088]
Next, using the generated passphrase, the printer 30 generates a secret key by public key cryptography (step S260). The passphrase used in step S260 is the same as the passphrase used in step S88 in the above-described public key generation process unless the installation position of the printer 30 has been moved. Therefore, a secret key corresponding to the public key generated in step S90 is generated. Subsequently, the printer 30 decrypts the received print transmission data D10 using the generated secret key to obtain the print data D05 (step S262).
[0089]
Next, the printer 30 determines whether the print transmission data D10 has been successfully decrypted using the secret key (step S264). If the decryption has succeeded (step S264: Yes), the printing that drives the print engine 52 is executed based on the obtained print data D05 (step S266). Specifically, the language interpretation of the print data D05 is performed, and print request data suitable for the print engine 52 is generated. By transmitting the print request data to the print engine 52, the print engine 52 performs printing on a print sheet or the like.
[0090]
When the printing is completed normally, the printer 30 transmits a print completion notification to the effect that the printing has been completed to the print client 20 as print result information (step S268).
[0091]
On the other hand, if it is determined in step S264 that the print transmission data D10 could not be decrypted (step S264: No), a decipherable notification is transmitted to the print client 20 as print result information (step S270). ).
[0092]
After step S268 or step S270, the printer 30 terminates the connection with the print client 20 (step S272). Then, the process returns to step S250.
[0093]
As described above, according to the printing system of the present embodiment, the public key of the printer 30 is generated by the printer 30 only when the authorized person who has been authenticated by the service provider 15 gives an instruction. Which can be stored by the printer 30. For this reason, the installation position where the printer 30 can perform normal printing can be limited.
[0094]
That is, the service provider 15 determines whether or not the person who has requested the generation of the public key is a person having valid authority based on the public key generation authentication information. Only when the service provider 15 determines that the public key generation authentication information matches, the printer 30 acquires at least the printer position information of the printer 30 at that time and uses the passphrase including the printer position information. Then, a public key is generated and held in the printer 30. On the other hand, if the service provider 15 determines that the user does not have the right, the printer 30 does not generate a public key.
[0095]
Then, the printer 30 transmits the public key to the print client 20 based on a request from the user. The print client 20 stores the public key transmitted from the printer 30 on the hard disk 76. When transmitting the print data D05 to the printer 30, the print client 20 transmits the print data D05 as print transmission data D10 encrypted using the public key. Each time the printer 30 receives the print transmission data D10, the printer 30 acquires the printer position information at that time, and generates a secret key using a passphrase including the printer position information. Then, the printer 30 decrypts the print transmission data D10 using the secret key. If the decryption is successful, the printer 30 performs printing. If the decryption is not successful, the printer 30 does not perform printing. Therefore, if the printer position information when the public key is generated in the printer 30 and the printer position information when the private key is generated in the printer 30 are different, the received print transmission data D10 cannot be properly decrypted. And a normal print result cannot be obtained. As a result, the position where the printer 30 can be used can be limited to a position where a person having valid authority instructs the generation of the public key.
[0096]
In addition, an operator having valid authority can obtain the authentication of the service provider 15 and instruct the printer 30 to generate the public key as many times as possible. This printer 30 can be used continuously even when the installation location of the printer 30 is changed. That is, if an operator having valid authority requests the service provider 15 again for authentication at a new installation location of the printer 30, a new public key is transmitted to the printer 30 based on the printer position information of the location. Generated. Therefore, the printer 30 can be effectively used.
[0097]
Note that the present invention is not limited to the above embodiment, and can be variously modified. For example, in the embodiment described above, the service provider 15 is described as being connected to the print client 20 via the network NT, but may be connected to another print client. Further, the service provider 15 may be connected to a computer other than the print client. Further, the printer 30 may be directly connected to the network NT.
[0098]
Further, in each of the above-described embodiments, the public key generation authentication information indicating whether or not the operator has valid authority is configured by a combination of an ID and a password. It is not limited to the combination. For example, the fingerprint of a person having the right authority is registered in the service provider 15, the fingerprint of the operator is read and transmitted to the service provider 15, and when the fingerprints match, the person has the right authority. May be determined.
[0099]
Also, a printer has been described as an example of a data receiving device that restricts usable positions, but the present invention is not limited to a printer. Further, the data transmission device is not limited to the print client.
[0100]
For example, the data transmission device in the data transmission / reception system may be a digital camera for capturing images, and the data reception device may be a data server that stores image data captured by the digital camera. In this case, the data transmitted from the digital camera is encrypted using a public key generated by the data server, and the data server receiving the data generates a secret key by the above-described method and generates a secret key. Decryption will be performed. Then, if the received data can be decoded, the data is stored, and if not, the data is not stored.
[0101]
Further, the data transmission device in the data transmission / reception system may be a personal computer, and the data reception device may be a projector that projects image data transmitted from the personal computer. In this case, the data transmitted from the personal computer is encrypted using the public key generated by the projector, and the projector receiving this data generates a secret key by the above-described method, and decrypts the data. Will do. Then, when the received data can be decoded, the data is projected, and when the received data cannot be decoded, the data is not projected.
[0102]
Further, the data transmission device in the data transmission / reception system may be a content server such as music, and the data reception device may be a device for reproducing content data such as music transmitted from the content server. In this case, the data transmitted from the content server is encrypted using the public key generated by the playback device, and the playback device receiving this data generates the secret key by the above-described method, and Decryption will be performed. Then, if the received data can be decoded, the data is reproduced, and if not, the data is not reproduced.
[0103]
Further, in the above-described embodiment, the case where the print medium of the printer 30 is a print sheet has been described as an example, but the print medium is not limited to this, and for example, another print medium such as an OHP sheet may be used. The present invention can be applied.
[0104]
Further, for each process described in the above embodiment, a program for executing each process is recorded on a recording medium such as a flexible disk, a CD-ROM (Compact Disc-Read Only Memory), a ROM, and a memory card. Thus, it can be distributed in the form of a recording medium. In this case, the above-described embodiment can be realized by causing the service provider 15, the print client 20, and / or the printer 30 to read and execute the recording medium on which the program is recorded.
[0105]
In addition, the service provider 15, the print client 20, and / or the printer 30 may include another program such as an operating system or another application program. In this case, the program provided by the service provider 15, the print client 20, and / or the printer 30 is used as the recording medium by utilizing other programs provided in the service provider 15, the print client 20, and / or the printer 30. An instruction for calling a program for realizing the same processing as the mode may be recorded.
[0106]
Further, such a program can be distributed not as a recording medium but as a carrier wave through a network. The program transmitted in the form of a carrier wave over the network is taken into the service provider 15, the print client 20, and / or the printer 30, and the above-described embodiment can be realized by executing the program.
[0107]
Further, when a program is recorded on a recording medium or transmitted as a carrier over a network, the program may be encrypted or compressed. In this case, the service provider 15, the print client 20, and / or the printer 30, which read the program from the recording medium or the carrier wave, need to execute the program after decoding and decompressing the program.
[0108]
【The invention's effect】
As described above, according to the printing system of the present invention, a printing system including a printing client, a printer that performs printing based on a request from the printing client, and at least a service provider connected to the printing client In, the position where the printer performs normal printing can be limited to the position of the printer when the printer generates the public key.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a configuration of a printing system according to an embodiment of the present invention.
FIG. 2 is a diagram showing an example of a hardware configuration of a printer according to an embodiment of the present invention.
FIG. 3 is a diagram showing an example of a configuration of a print client according to an embodiment of the present invention.
FIG. 4 is a diagram showing an example of a configuration of a service provider according to an embodiment of the present invention.
FIG. 5 is a conceptual diagram illustrating encryption and decryption of print data using a public key and a secret key in one embodiment of the present invention.
FIG. 6 is a flowchart illustrating a public key generation request process executed by the print client according to the embodiment of the present invention.
FIG. 7 is a view showing a flowchart illustrating an authentication process executed by the service provider according to the embodiment of the present invention.
FIG. 8 is a flowchart illustrating a public key generation process performed by the printer according to the embodiment of the present invention.
FIG. 9 is a view showing an example of a configuration of a public key storage unit provided in the printer according to the embodiment of the present invention.
FIG. 10 is a flowchart illustrating a public key request process executed by the print client according to the embodiment of the present invention.
FIG. 11 is a view showing an example of the configuration of a public key table provided in a print client according to an embodiment of the present invention.
FIG. 12 is a flowchart illustrating a public key transmission process executed by the printer according to the embodiment of the present invention.
FIG. 13 is a flowchart illustrating a print request process executed by the print client according to the embodiment of the present invention.
FIG. 14 is a flowchart illustrating a print execution process executed by the printer according to the embodiment of the present invention.
[Explanation of symbols]
NT Network
10 Cable
15 Service Provider
20 Print Client
30 Printer
40 CPU
42 RAM
44 ROM
46 Internal bus
48, 50, 56 interface
52 Print Engine
54 Position detector
58 Hard Disk
60 Computer body
62 Display
64 CPU
66 RAM
68 ROM
70 Internal bus
72, 73, 74, 78 interface
76 Hard Disk

Claims (8)

A print system comprising: a print client; a printer that performs printing based on a request from the print client; and a service provider connected to at least the print client.
The printer includes a printer position information acquisition unit that acquires printer position information for specifying a place where the printer is installed,
The service provider includes a determination unit configured to determine whether or not the user has a legitimate authority regarding generation of a public key,
The printer obtains printer position information from the printer position information obtaining means when the determination means of the service provider determines that the person has a right to generate a public key, and transfers the printer position information to the first printer. Public key generation means for generating a public key using a passphrase including at least the first printer position information as the position information,
A printing system, characterized in that: The printing system according to claim 1, wherein the printer further includes a first public key storage unit that stores the public key generated by the public key generation unit. The printer further includes a public key transmitting unit that reads a public key from the public key first storage unit and transmits the public key to the print client.
The print client further includes a public key second storage unit that stores a public key received from the printer.
3. The printing system according to claim 2, wherein: The print client,
Print data generating means for generating print data for printing by the printer,
A print data transmitting unit that reads a public key from the public key second storage unit, encrypts the print data with the public key, and transmits the encrypted print data to the printer;
With
The printer further comprises:
Receiving print data encrypted with the public key, print data receiving means,
A second printer position information acquisition unit that acquires printer position information from the printer position information acquisition unit when the print data is received, and uses the acquired printer position information as second printer position information;
Secret key generation means for generating a secret key using a passphrase including at least the second printer position information;
Using the secret key, decrypt the print data received by the print data receiving means, decryption means,
The printing system according to claim 3, further comprising: The print client further includes an authentication information requesting unit for requesting authentication information from an operator,
The determination means of the service provider obtains the input authentication information and determines whether or not the input authentication information matches the registered authentication information. Judge that he has
The printing system according to claim 4, wherein: 6. The private key is discarded even when a private key is generated when the public key generating means of the printer generates a public key. Printing system. The printer executes printing based on the print data when the print data can be decrypted using the secret key, and executes the printing based on the print data when the print data cannot be decrypted using the secret key. The printing system according to any one of claims 1 to 6, further comprising a selective print execution unit that does not execute printing based on the print data. A method for controlling a printing system, comprising: a print client, a printer that performs printing based on a request from the print client, and at least a service provider connected to the print client,
The service provider determining whether the person who has requested the generation of the public key is a person who has valid authority with respect to the generation of the public key,
When the service provider determines that the person who has requested the generation of the public key is a person who has valid authority regarding the generation of the public key, the location where the printer is installed is specified from the printer position information obtaining means. Acquiring printer position information for use as the first printer position information, and generating a public key using a passphrase including at least the first printer position information;
A method for controlling a printing system, comprising:

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