JPH1091376A - Printing system, information processor, printer and printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep document data sufficiently secret even when information processors share a printer on a communication network. SOLUTION: When coded data converted by a host computer are inputted to a laser printer, a table command indicating a decoding table is written in the input data and in this case, it is judged whether or not the decoding table indicated by the table command is stored in a coding ROM (S11→S12→S13). Then the coding ROM is previously stored with decoding tables and when there is the decoding table matching the table command among the decoding tables, the decoding table is used to reconvert the coded data into document data (S14), which are printed (S15).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a printing system, and an information processing apparatus and a printing apparatus constituting the printing system.
And a printing method.

[0002]

2. Description of the Related Art Conventionally, in a printing system of this type, as a method for preventing the secret leakage of communication contents, (1) a printing apparatus is configured to be able to print only through a specific password, and The printing operation is not executed unless a specific password is input. (2) The printing apparatus distributes a specific sorter for each user and provides a key dedicated to each sorter, and only the user having the key is accommodated in the sorter. A method of taking out a printed matter is known.

[0003]

However, a plurality of host computers are connected on a network (communication network), and the plurality of host computers are, for example, one.
In the case where one printing apparatus is shared and used, when a certain host computer causes the printing apparatus to print document data via a network, a third party is connected to another host connected to the network. It is possible to monitor the document data using a computer. That is, in the conventional printing system, the content of the document data can be intercepted by monitoring the document data, so that there is a problem that the communication security is insufficient. That is, the document data for printing is input in a language that can be analyzed by the printing device, but since these languages are languages well known to the general public, a third party can easily steal, For this reason, the conventional printing system has a problem that the security (confidentiality) of communication cannot be sufficiently guaranteed.

[0004] The present invention has been made in view of the above-described problems, and secures sufficient confidentiality of document data even when a plurality of information processing apparatuses share a printing apparatus on a communication network. It is an object of the present invention to provide a printing system, an information processing apparatus, a printing apparatus, and a printing method that can perform printing.

[0005]

According to a first aspect of the present invention, a plurality of information processing apparatuses are connected to at least one or more printing apparatuses via a predetermined communication network. In a printing system in which the information processing apparatus shares the printing apparatus, the information processing apparatus determines whether to encrypt the document data, and when the determination section determines that the document data should be encrypted. Comprises encryption means for encrypting document data, and encrypted data output means for outputting the encrypted data encrypted by the encryption means to the printing device, wherein the printing device comprises an encrypted data output means. And a document data output means for printing and outputting the document data based on the decoding result of the decoding means.

According to a seventh aspect of the present invention, an information processing apparatus connected to at least one or more printing apparatuses via a predetermined communication network determines whether or not to encrypt document data. Encrypting means for encrypting the document data when the encrypting means determines that the document data should be encrypted;
And an encrypted data output unit for outputting the encrypted data encrypted by the encryption unit to the printing apparatus.

According to a twelfth aspect of the present invention, in a printing apparatus connected to a plurality of information processing apparatuses via a predetermined communication network, decryption means for decrypting encrypted data from the information processing apparatus, Document data output means for printing and outputting the document data based on the decoding result of the decoding means.

[0008] According to a seventeenth aspect of the present invention, a plurality of information processing apparatuses and at least one or more printing apparatuses are connected via a predetermined communication network, and predetermined data is transmitted from the plurality of information processing apparatuses to the printing apparatuses. In the printing method for outputting a printed matter from the printing apparatus, the information processing apparatus determines whether or not to encrypt the document data, and when it is determined that the document data should be encrypted, encrypts the document data. While outputting the encrypted data to the printing device, the printing device receiving the encrypted data decrypts the encrypted data, and then prints and outputs the document data based on the decryption result. And

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a system configuration diagram showing an embodiment of a printing system according to the present invention. The printing system includes a plurality of host computers (first to third host computers 1 to 3), Laser beam printers 4 as printing devices are connected to each other via a network (communication network) 5 such as a LAN. The first to third host computers 1 to 3 are connected to one laser beam printer 4.
, And the laser beam printer 4 outputs a printed matter based on commands from the first to third host computers 1 to 3.

FIG. 2 is a diagram showing the internal structure of the laser beam printer 4. The laser beam printer 4 includes an operation panel 7 having a switch section, an LED display section, and the like provided on the upper surface of an apparatus body 6, and a predetermined section. A printing main body (printer engine) 8 for performing a printing operation, and an encryption ROM 9 described later.
And a print control device 10 that analyzes the input character data and control data and controls the printing operation of the printing main body 8.

The printing main unit 8 stores predetermined recording paper (cut paper) and supplies the recording paper via a paper feed cassette 12 having a paper feed roller 11 and an appropriate number of transport rollers 13. An electrostatic drum 14 to be irradiated, an optical system 15 for irradiating the electrostatic drum 14 with laser light, a developing device 16 containing toner of a predetermined color and disposed around the electrostatic drum 14, A fixing unit 17 for fixing the toner image developed by the developing unit 16; and a paper discharge unit 19 for discharging document data and the like printed on the recording paper to the outside of the apparatus via a paper discharge roller 18.
And

The optical system 15 includes a semiconductor laser 20 for emitting laser light of a predetermined wavelength,
0, a laser driver 21 that drives
And a reflecting mirror 23 that reflects the laser light that enters through the rotating polygon mirror 22 and supplies the laser light onto the electrostatic drum 14.

In the laser beam printer 4 configured as described above, a video signal from the print control device 10 is input to the laser driver 21 to turn on / off the laser light emitted from the semiconductor laser 20 in accordance with the video signal. Switch off. The laser light is swung right and left by a rotating polygon mirror 22 to scan on the electrostatic drum 14,
An electrostatic latent image such as a character pattern is formed on the top,
The electrostatic latent image is developed via a developing device 16. And
The toner image adhered on the electrostatic drum 14 is supplied to the paper feed cassette 1
2 is transferred to the recording paper fed from
7, the toner image is fixed on the recording paper, and the recording paper is discharged to a paper discharge unit 19 via a paper discharge roller 18.

FIG. 3 is a block diagram showing a control system of the laser beam printer 4. As shown in FIG.

That is, the printing control device 10 is connected to the network 5 and connected to the first to third host computers 1.
3, a network interface (I / F) 24 for exchanging data with the print main unit 8, a print main unit interface (I / F) 25 for controlling an interface operation with the print main unit 8, and an encryption ROM 9. A memory controller (MC) 26 for controlling access, a printer RAM 27 having an output information expansion area, an environment information storage area, an NVRAM, etc., a printer ROM 28 in which predetermined information is stored in advance, and a system bus 29 And a printer CPU 30 which is connected to the above-mentioned components and controls these components.

The printer ROM 28 includes a font ROM 31 in which font data and the like used when generating output information to the printing main unit 8 are stored, and a program ROM 32 in which a predetermined control program is stored. Have.

The encryption ROM 9 has a non-volatile memory, and has an MC 26 via a connector (not shown).
It is detachable from. Furthermore, the encryption ROM 9
Stores a plurality of decryption tables for decrypting encrypted data in the non-volatile memory, and decrypts encrypted document data from the first to third host computers 1 to 3.

The printer CPU 30 controls the access to various devices connected to the system bus 29 based on the control program stored in the program ROM 32, and controls the network 5 and the network I / F 24. And analyzes the document data input from the first to third host computers 1 to 3 through the CPU, converts the document data into a dot pattern by referring to the encryption ROM 9 and the font ROM 31, and converts the dot pattern into a printer pattern. After temporarily storing it in the RAM 29, the print main body I /
An image signal is output as output information to the printing main unit 8 connected via F25.

FIG. 4 is a block diagram showing a control system of the first host computer 1.

Since the second and third host computers 2 and 3 have the same configuration, the description of the second and third host computers 2 and 3 will be omitted.

Thus, the first host computer 1
Is a keyboard 33 on which arbitrary predetermined information is input by an operator, and a display unit (CR) for displaying the predetermined information and the like.
T) 34 and an external storage device 3 such as a flexible disk or a hard disk in which a boot program, various application programs, font data, user files, an encryption table and an edit file described later are stored.
5 and an information control device 36.

The information control device 36 includes a keyboard 3
And a keyboard controller (KBC) 37 for controlling key input information from the PC 3 and input information specified by a pointing device (not shown), and a CR for controlling the CRT 34.
T controller (CRTC) 38 and external storage device 35
Disk controller (DK) that controls access to
C) 39, a network interface (I / F) 40 connected to the network 5, and a RAM 4 that stores input information and has a function as a work area.
1, a ROM 42 in which predetermined information is stored in advance,
A CPU 44 is connected to each of the above components via a system bus 43 and controls these components.

The ROM 42 is a font ROM in which font data and the like used during document processing are stored.
45, a program ROM 46 in which an encryption processing program described later and a predetermined document processing program are stored,
A data ROM 47 in which various data used for performing the document processing are stored; and a CPU 44 executes a RAM 41 for processing a document in which graphics, images, characters, tables (including spreadsheets, etc.) are mixed, and a work area. In accordance with the above document program. That is, the CPU 44
Executes rasterization of the outline font in the display information area provided in the RAM 41,
Wig Wig on RT44 (WYSIWIG: What Y
ou See Is What You Get), and the information displayed on the CRT 44 is printed out as it is. CPU4
Reference numeral 4 opens various registered windows based on command information specified by a pointing device or the like, and executes various data processing.

Next, a case where document data is transmitted from the first host computer 1 to the laser beam printer 4 and a printed matter is output from the laser beam printer 4 will be described with reference to FIGS.

FIG. 5 is a flowchart of a host-side processing procedure executed by the host computer.

In step S1, document data is created based on the document processing program stored in the program ROM 46 in the information processing device 36. In the following step S2, it is determined whether or not to encrypt the document data. In other words, although the confidentiality of the document data is ensured by performing the encryption, the encryption work in the first host computer 1 and the decryption work of the laser beam printer 4 require time, so that it is necessary to keep the secret. If the document data is not encrypted, the print result can be obtained more quickly if the document data is not encrypted. Therefore, step S2
Then, it is determined whether or not document data should be encrypted.

If the document data is not to be encrypted, the process proceeds to step S4. If the document data is to be encrypted, the encryption table is read from the external storage device 35 and the document data is encrypted.

FIG. 6 is a table showing an example of the encryption table, in which 2-byte document data is converted into encryption. That is, the horizontal axis is the lower byte, and the vertical axis is the upper byte. For example, the document data “0000” is converted into a code “0A0F” as shown in FIG. To the code "0C
0E ”.

Next, in step S4, data to be transmitted to the laser beam printer 4 is created, and the data is output to the laser beam printer 4 via the network I / F 40.

That is, the data to be transmitted to the laser beam printer 4 is prefixed with an address code 48 indicating that the data is to be transmitted to the laser beam printer 4 as shown in FIG. Table command 49 indicating which of the decryption tables to use, an encryption code 50 indicating the encrypted document data, and an END indicating the end of data transmission.
The code 51 is attached. The document data encrypted in this manner is transmitted to the laser beam printer 4 via the network 5, and in this case, the second and third host computers 2, 3 connected to the network 5 When the document data is encrypted, the document data is encrypted, and the second or third host computer 2 or 3 cannot know the decryption method. Of the host computers 2 and 3.

When the document data is not encrypted, the document data is transmitted to the laser beam printer 4 as it is.

Next, the process proceeds to step S5, where
It is determined whether or not the table command 49 specified in step 4 is not present in the encryption ROM 9 from the laser beam printer 4, and if the answer is negative (No), the processing in the first host computer 1 is terminated. That is, in this case, as described later, a decryption operation on the document data is performed based on the encryption code.

On the other hand, the answer to step S5 is affirmative (Yes).
In the case of, the fact that there is no decryption table is displayed on the CRT 34, and the process is terminated.

FIG. 8 is a flowchart of a printer-side processing procedure executed by the laser beam printer 4.

In step S11, it is determined whether or not the data created in step S4 has been input. If the data has not been input, the process waits until the data is input. It is determined whether or not a table command designating a decryption table is written in step S12. If the table command has not been written, the process proceeds to step S15,
If a table command has been written, it is determined whether or not there is a decoding table specified by the table command (step S13). If there is a decryption table, the encryption code is inversely converted into document data using the decryption table (step S14).

FIG. 9 is a table diagram showing an example of the decryption table, which is a decryption table corresponding to the above-described encryption table of FIG. That is, as described above, the document data "0000" is converted into the encryption code "0A0F" and transmitted to the laser beam printer 4, and the encryption code "0A0F" is converted by the laser beam printer 4 according to the decryption table. As shown in FIG.
00 ", and the encryption code" 0C0E "is
Is converted back to document data "0001" as shown in FIG.

Next, in step S15, printing of the document data is performed, and the process is terminated. That is, the decrypted document data is converted into a character pattern by referring to the font ROM 31 according to the instruction of the control code, and other graphic data is converted into a dot pattern in the same manner as in a normal printing operation. Are stored in the printer RAM 27 as dot pattern data. The dot pattern data is stored in the print main body I / F2.
The printing is performed by the print main unit 8 via the control unit 5.

On the other hand, if it is determined in step S13 that the decryption table specified by the table command is not stored in the encryption ROM 9, it is displayed on the operation panel 7 that there is no decryption table, and the first host computer 1 Is notified that there is no decryption table (step S16), and the process ends.

As described above, in the present embodiment, document data is encrypted by the first host computer 1 for data that needs to be kept secret, and the encrypted document data is transmitted to the laser beam printer 4. By decoding and outputting at the other host computer, ie, the second
Alternatively, the document data can be output to the laser beam printer 4 without being stolen from the third host computers 2 and 3, and the confidentiality of communication on the network 5 can be ensured.

FIG. 10 is a block diagram showing another embodiment of the laser beam printer 4. The laser beam printer 4 has an input unit 52 separately from the network I / F 24. In the other embodiment, a dedicated line 54 different from the network 5 is provided via the input unit 52.
The laser beam printer 4 and the first host computer 1 are connected to each other, and a decoding table from the first host computer 1 is input to the input unit 52 through the dedicated line 54 in advance, and the rewritable flash memory And the like, and the decoding table is stored in the non-volatile memory 53.

In this embodiment, the decoding table is transmitted to the first host computer 1 via the dedicated line 54.
Is transmitted directly to the laser beam printer 4, the risk of the contents of the decoding table being decoded by a third party on the network can be avoided, and the confidentiality of the communication contents can be improved. Further, since the nonvolatile memory 53 is rewritable, the decoding table can be updated. Further, the nonvolatile memory 5
By fixing the 3 to the MC 26 so that it cannot be detached, the confidentiality can be further improved.

It is needless to say that the present invention is not limited to the above embodiment. In the above-described embodiment, the encrypted document data is decrypted by the decryption table. However, the decryption may be performed by an arithmetic unit necessary for decryption. For example, when the document data to be encrypted is rotated one bit to the right and encrypted, the encrypted document data can be decrypted by associating the data with an external storage device so that the data is rotated one bit to the left. it can.

[0044]

As described above in detail, according to the claims of the present invention, even if document data is transmitted from an information processing apparatus to a printing apparatus connected to a predetermined communication network, a predetermined Confidentiality of communication on the communication network can be ensured.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a printing system according to the present invention.

FIG. 2 is an internal structural diagram of the laser beam printer.

FIG. 3 is a block diagram showing a control system of the laser beam printer.

FIG. 4 is a block diagram showing a control system of the host computer.

FIG. 5 is a flowchart illustrating a host-side processing procedure.

FIG. 6 is a table diagram showing an example of an encryption table.

FIG. 7 is a data format diagram showing an example of data to be transmitted to a laser beam printer.

FIG. 8 is a flowchart illustrating a processing procedure on the printer side.

FIG. 9 is a table diagram showing an example of a decryption table.

FIG. 10 is a block diagram showing another embodiment of the control system of the laser beam printer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 1st host computer (information processing apparatus) 2 2nd host computer (information processing apparatus) 3 3rd host computer (information processing apparatus) 4 Laser beam printer (printing apparatus) 5 Network (predetermined communication network) 9 Encryption ROM (non-volatile storage means) 25 print main unit I / F (document data output means) 30 printer CPU (decoding means, notification means) 34 CRT (display means) 35 external storage device 40 network I / F (encrypted data) Output means, transmission means) 44 CPU (determination means, encryption means) 51 input section (reception means) 53 non-volatile memory (non-volatile storage means) 54 dedicated line

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04L 9/06 H04L 9/00 611Z

Claims (22)

[Claims] 1. A printing system in which a plurality of information processing apparatuses and at least one or more printing apparatuses are connected via a predetermined communication network, and wherein the plurality of information processing apparatuses share the printing apparatuses. Means for determining whether or not to encrypt the document data, encryption means for encrypting the document data when the determination means determines that the document data should be encrypted, and encryption by the encryption means. Encrypted data output means for outputting the encrypted data to the printing apparatus, wherein the printing apparatus decrypts the output result of the encrypted data output means, and based on the decryption result of the decryption means And a document data output unit for printing and outputting the document data. 2. The printing method according to claim 1, wherein an external storage device is connected to the information processing device, and an encryption table for encrypting the document data is stored in the external storage device. system. 3. A removable nonvolatile storage means is connected to the printing apparatus, a plurality of decryption tables are stored in the nonvolatile storage means, and the decryption means performs encryption from among the plurality of decryption tables. 3. The printing system according to claim 1, wherein a decoding table corresponding to an output result of the data output means is selected and decoded. 4. A rewritable nonvolatile storage means is fixed to the printing apparatus, and the specific information processing apparatus and the printing apparatus are connected to a dedicated line other than the predetermined communication network. 3. The printing system according to claim 1, further comprising a transmission unit configured to transmit a decryption table for decrypting the encrypted data to the printing device via the dedicated line. 4. 5. When the decryption table corresponding to the output result of the encrypted data output unit is not stored in the nonvolatile storage unit, the printing apparatus notifies the information processing apparatus that the decryption table does not exist. The printing system according to claim 3, further comprising a notification unit, wherein the information processing apparatus includes a display unit configured to display a notification result of the notification unit. 6. The encryption means has encrypted data creation means for calculating and creating encrypted data, and the decryption means calculates the encrypted data created by the encrypted data creation means. 2. The printing system according to claim 1, further comprising: decryption data creating means for decrypting the data. 7. An information processing device connected to at least one or more printing devices via a predetermined communication network, for determining whether or not to encrypt the document data;
Encrypting means for encrypting document data when the determining means determines that the data should be encrypted; and encrypted data output means for outputting the encrypted data encrypted by the encrypting means to the printing apparatus. An information processing apparatus comprising: 8. The information processing apparatus according to claim 7, wherein an external storage device is connected, and an encryption table for encrypting the document data is stored in the external storage device. 9. A transmission means connected to the printing device via the predetermined communication network and the dedicated line, and transmitting a decryption table for decrypting the encrypted data to the printing device via the dedicated line. The information processing apparatus according to claim 7, wherein the information processing apparatus performs the processing. 10. The printing apparatus according to claim 7, further comprising display means for displaying that the decrypted data does not exist when the decrypted data corresponding to the encrypted data does not exist in the printing apparatus. 10. The information processing apparatus according to any one of 9. 11. The information processing apparatus according to claim 7, wherein said encryption means has an encrypted data creation means for calculating and creating encrypted data. 12. A printing device connected to a plurality of information processing devices via a predetermined communication network, wherein the decoding device decodes encrypted data from the information processing device, and A printing apparatus comprising: document data output means for printing and outputting document data. 13. A removable nonvolatile storage means is connected, a plurality of decryption tables are stored in said nonvolatile storage means, and said decryption means corresponds to said encrypted data from said plurality of decryption tables. 13. The printing apparatus according to claim 12, wherein the decryption table is selected and decrypted. 14. A rewritable nonvolatile storage means is fixed, connected to the information processing device via the predetermined communication network and a dedicated line, and transmitted from the information processing device via the dedicated line. 13. The printing apparatus according to claim 12, further comprising a receiving unit that receives a decryption table for decrypting the encrypted data. 15. When the decryption table corresponding to the encrypted data is not stored in the non-volatile storage means, the information processing apparatus has a notifying means for notifying the information processing apparatus that the decryption table does not exist. The printing apparatus according to any one of claims 12 to 14, wherein: 16. The printing apparatus according to claim 12, further comprising decryption data creating means for calculating and decrypting the encrypted data. 17. A plurality of information processing apparatuses and at least one or more printing apparatuses are connected via a predetermined communication network, and transmit predetermined data from the plurality of information processing apparatuses to the printing apparatus, and In the printing method for outputting a printed matter, after the information processing apparatus determines whether or not to encrypt the document data, when it is determined that the document data should be encrypted, the document data is encrypted, and the encrypted encrypted data is transmitted. A printing method, wherein while outputting to the printing device, the printing device receiving the encrypted data decrypts the encrypted data, and then prints and outputs the document data based on the decryption result. 18. The printing method according to claim 17, wherein the external storage device stores an encryption table, reads the stored encryption table, and encrypts the document data. 19. A decryption table storing a plurality of decryption tables in a removable nonvolatile storage means, and decrypting by selecting a decryption table corresponding to encrypted data from the plurality of decryption tables. Claim 17 or Claim 1
8. The printing method according to item 8. 20. A rewritable nonvolatile storage means is fixed to a printing apparatus, and the information processing apparatus and the printing apparatus are connected to a dedicated line other than the predetermined communication network to decrypt the encrypted data. 19. The printing method according to claim 17, wherein the decryption table is transmitted from the information processing device to the nonvolatile storage unit via the dedicated line. 21. When the decryption table corresponding to the encrypted data is not stored in the nonvolatile storage means, the printing apparatus notifies the information processing apparatus that the decryption table does not exist, and the information processing apparatus Displaying a notification result from the printing apparatus.
The printing method according to claim 20. 22. The printing method according to claim 17, wherein the encrypted data is calculated and generated, and the generated encrypted data is calculated and decrypted.