Image forming device and data deleting method

Abstract

To provide an image forming device and a data deleting method in which data recorded in the image forming device can be deleted in a short time while the confidentiality is maintained.SOLUTION: A setting processing unit 113 that, after data in a data storage region of an HDD 171 in an image forming device 1 is completely deleted, formats a portion of the HDD 171 and sets the portion of the storage region as an available region. An execution processing unit 112 executes a function corresponding to the available region in the image forming device 1. A deletion processing unit 114 deletes data to be recorded in the available region when the function is executed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a technique for erasing data recorded in a storage device of an image forming apparatus. [Background technology]

[0002] An image forming apparatus has a built-in hard disk drive (hereinafter referred to as HDD), and various data such as image data, system information, user information, etc. Conventionally, techniques for erasing data from the HDD to prevent information leakage, etc., of such data have been known (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-174862 A [Patent Document 2] JP 2005-203066 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, the time required to erase data has increased as the capacity of HDDs has increased. In addition, due to growing security awareness, there is a demand for reliable erasure of highly confidential data. However, with conventional technology, it is difficult to erase data in a short time while maintaining confidentiality.

[0005] An object of the present invention is to provide an image forming apparatus and a data erasing method that are capable of erasing data recorded in the image forming apparatus in a short period of time while maintaining confidentiality. [Means for solving the problem]

[0006] According to one aspect of the present invention, an image forming apparatus includes a setting processor, an execution processor, and an erasure processor. After all data in a storage area of ​​a data storage device in the image forming apparatus is erased, the setting processor formats a part of the storage area and sets the part of the storage area as an available area. The execution processor executes a function corresponding to the available area in the image forming apparatus. The erasure processor erases data recorded in the available area by executing the function.

[0007] A data erasure method according to another aspect of the present invention includes a setting step, an execution step, and an erasure step. In the setting step, after all data in a storage area of ​​a data storage device in an image forming device is erased, a part of the storage area is formatted and the part of the storage area is set as an available area. In the execution step, a function corresponding to the available area is executed in the image forming device. In the erasure step, data recorded in the available area by executing the function is erased. Effect of the Invention

[0008] According to the present invention, it is possible to provide an image forming apparatus and a data erasing method that are capable of erasing data recorded in the image forming apparatus in a short period of time while maintaining confidentiality. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing a configuration of an image forming apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an example of a data erasure method in a Normal Erase mode of a Secure Erase command according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a diagram showing an example of a data erasure method in the Enhanced Erase mode of the Secure Erase command according to an embodiment of the present invention. [Figure 4]FIG. 4 is a flowchart showing an example of a procedure of a data erasure process executed in the image forming apparatus according to the embodiment of the present invention. [Diagram 5] FIG. 5 is a diagram showing a specific example of a data erasure process executed in the image forming apparatus according to the embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing a specific example of a data erasure process executed in the image forming apparatus according to the embodiment of the present invention. [Figure 7] FIG. 7 is a diagram showing a specific example of a data erasure process executed in the image forming apparatus according to the embodiment of the present invention. [Figure 8] FIG. 8 is a diagram showing a specific example of a data erasure process executed in the image forming apparatus according to the embodiment of the present invention. [Figure 9] FIG. 9 is a diagram showing a specific example of a data erasure process according to another embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing a specific example of a data erasure process according to another embodiment of the present invention. [Figure 11] FIG. 11 is a diagram showing a specific example of a data erasure process according to another embodiment of the present invention. [Figure 12] FIG. 12 is a diagram showing a specific example of a data erasure process according to another embodiment of the present invention. [Figure 13] FIG. 13 is a diagram showing a specific example of a data erasure process according to another embodiment of the present invention. [Figure 14] FIG. 14 is a diagram showing a specific example of a data erasure process according to another embodiment of the present invention. [Figure 15] FIG. 15 is a diagram showing a specific example of a data erasure process according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings to facilitate understanding of the present invention. Note that the following embodiment is an example of the present invention and does not limit the technical scope of the present invention.

[0011] [Image forming device 1] 1, the image forming apparatus 1 includes a control unit 11, an operation display unit 12, an ADF (Auto Document Feeder) 13, an image reading unit 14, an image forming unit 15, a communication I / F 16, a storage unit 17, etc. Specifically, the image forming apparatus 1 is a multifunction machine having a printer function, a scanner function, a copy function, a facsimile function, etc. Note that the image forming apparatus of the present invention is not limited to a multifunction machine, and can be applied to any image forming apparatus such as a copy machine, a printer, or a facsimile machine.

[0012] The operation display unit 12 includes a display unit such as a liquid crystal display that displays information, and an operation unit such as a touch panel and operation buttons that accept user operations.

[0013] The ADF 13 is an automatic document feeder that includes a document setting section, a transport roller, a document holder, and a paper discharge section, and transports documents to be read by the image reading section 14 .

[0014] The image reading unit 14 includes a document table, a light source, a mirror, an optical lens, and a CCD (Charge Coupled Device), and is capable of reading an image of a document and outputting the image as image data.

[0015] The image forming unit 15 is capable of performing a print process based on image data by an electrophotographic method or an inkjet method, and forms an image on a sheet based on the image data. For example, when the image forming unit 15 is an electrophotographic image forming unit, the image forming unit 15 includes a photoconductor drum, a charger, an exposure device, a developing device, a transfer device, and a fixing device.

[0016] The communication I / F 16 is a communication interface capable of performing wired or wireless data communication with an external device. For example, the communication I / F 16 performs data communication with an external device via a network. The external device includes an operation terminal (personal computer, mobile terminal, smartphone, etc.) operated by a user, a storage device (external storage, USB device, etc.) that stores data, and the like.

[0017] The storage unit 17 is a non-volatile storage unit such as an HDD 171, a flash memory, or an EEPROM (registered trademark). The storage unit 17 stores various control programs executed by the control unit 11, various data, and the like. The control programs executed by the control unit 11 include a data erasure program for causing the control unit 11 to execute a data erasure process (see FIG. 4) described below.

[0018] Various data such as image data, document data, system information, and user information are recorded in the HDD 171. The HDD 171 is an example of a storage device of the present invention. The storage device of the present invention is not limited to an HDD, and may be an SSD (Solid State Drive) or the like.

[0019] Incidentally, in recent years, the time required to erase data has increased with the increase in HDD capacity. In addition, with growing security awareness, there is a demand for reliable erasure of highly confidential data. However, with conventional techniques, it is difficult to erase data in a short time while maintaining confidentiality. In contrast, the image forming apparatus 1 according to this embodiment is capable of erasing data recorded on the HDD in a short time while maintaining confidentiality, as described below.

[0020] The control unit 11 includes control devices such as a CPU, a ROM, and a RAM. The CPU is a processor that executes various arithmetic operations. The ROM is a non-volatile storage unit in which information such as a control program for causing the CPU to execute various processes is stored in advance. The RAM is a volatile or non-volatile storage unit used as a temporary storage memory (work area) for various processes executed by the CPU.

[0021] Specifically, the control unit 11 includes a reception processing unit 111, an execution processing unit 112, a setting processing unit 113, an erasure processing unit 114, etc. The control unit 11 functions as each of these processing units by executing various processes according to the data erasure program. The control unit 11 may also include an electronic circuit that realizes a part or a plurality of processing functions of each of these processing units.

[0022] The reception processing unit 111 receives various operations from a user. Specifically, when a user performs an operation such as a print instruction, a copy instruction, a scan instruction, or a setting change instruction on an operation terminal (user terminal) or the operation display unit 12, the reception processing unit 111 receives the operation.

[0023] The execution processing unit 112 executes processes (jobs) corresponding to various operations accepted by the acceptance processing unit 111. For example, the execution processing unit 112 executes a print job, a copy job, a scan job, a setting job, and the like.

[0024] The setting processing unit 113 executes various setting processes in the data erasure process. Specific examples of the setting processes will be described later.

[0025] The erasure processing unit 114 executes a process of erasing data recorded in the HDD 171. Here, the data erasure method includes a number of well-known methods. For example, the data erasure method includes the NSA method, the DoD method, the random number method, the format method, the BSI / VSITR method, and the Secure Erase command.

[0026] The NSA method is an erasure method that complies with the recommendations of the NSA (National Security Agency), and erases data recorded on HDD171 by writing data in the following order: "random number 1 (a predetermined random number) → random number 2 (a predetermined random number different from random number 1) → zero."

[0027] The DoD method is an erasure method that complies with U.S. Department of Defense standards, such as DoD 5220.22-M, and erases data recorded on HDD 171 by writing data in the order of "random number 1 → 1's complement of random number 1 → random number 2."

[0028] The random number method erases data recorded on the HDD 171 by overwriting it with different random numbers a number of times specified by the user or a preset number of times.

[0029] The format method is an erasure method that initializes (formats) the file system and does not erase data on a sector-by-sector basis.

[0030] The BSI / VSITR method is a German standard erasure method that erases data recorded on HDD171 by writing the following codes a total of seven times in the following order: "00", "FF", "00", "FF", "00", "FF", "AA".

[0031] The Secure Erase command is implemented in ATA and SATA HDD 171 and is approved by the National Institute of Standards and Technology. By executing the Secure Erase command, data can be erased quickly with a single overwrite. The procedure for erasing data using the Secure Erase command is to first set a user password in HDD 171 using the Security Set Password command, and lock the HDD 171 to prevent access to it. After locking the HDD 171, the Secure Erase command is issued to erase the data.

[0032] The Secure Erase command has a Normal Erase mode and an Enhanced Erase mode. The erasure processing unit 114 issues the Secure Erase command and uses the Normal Erase mode and the Enhanced Erase mode to erase data in the HDD 171. When the erasure processing unit 114 is set to the Normal Erase mode, it writes binary zeros to all user data areas in the HDD 171.

[0033] Furthermore, when the erase processing unit 114 is set to Enhanced Erase mode, it writes a preset data pattern to all previously written user data areas, including sectors that are no longer used due to reallocation. The "user data area" refers to all areas that are assigned LBAs (Logical Block Addresses), including the HPA and DCO. The "reallocated sector" refers to a sector that is determined to be a "bad sector" by the HDD 171 itself based on the frequency of read errors and read retries while the HDD 171 is in use (with the power on) after being shipped from the manufacturing factory, and that has lost its LBA after copying data to another sector dedicated to LBA reallocation.

[0034] The difference between the Normal Erase mode and the Enhanced Erase mode is whether or not overwriting is performed on the "reallocated sectors."

[0035] Fig. 2 is a conceptual diagram showing a specific example of a data erasing method in the Normal Erase mode, and Fig. 3 is a conceptual diagram showing a specific example of a data erasing method in the Enhanced Erase mode. In the Normal Erase mode, the erasing processor 114 erases only data in used sectors of the entire storage area of ​​the HDD 171, and in the Enhanced Erase mode, the erasing processor 114 erases data in the entire storage area (all sectors) of the HDD 171. In addition, if the HDD 171 includes a spare area or a management area, the erasing processor 114 also erases the data therein.

[0036] The erasure processing unit 114 uses an erasure method designated by the user to execute the process of erasing data recorded in the HDD 171. A specific example of the data erasure process will be described below.

[0037] [Data erasure process] An example of the procedure of the data erasure process executed by the control unit 11 of the image forming apparatus 1 will be described with reference to Fig. 4. Here, steps S11, S12, ... represent the numbers of the processing procedures (steps) executed by the control unit 11. The present invention can be understood as an invention of a data erasure method (corresponding to the data erasure method of the present invention) that executes one or more steps included in the data erasure process.

[0038] Also, one or more steps included in the data erasure process described here may be omitted as appropriate. Also, the steps in the data erasure process may be executed in a different order as long as the same action and effect is achieved. Furthermore, although an example is described here in which the control unit 11 executes each step in the data erasure process, in other embodiments, one processor may execute each step in the data erasure process, or multiple processors may execute each step in the data erasure process in a distributed manner. Also, a computer (image forming device 1, server, etc.) may execute each step in the data erasure process.

[0039] <Step S11> In step S11, control unit 11 determines whether or not it is time to start the process of erasing data recorded in HDD 171. For example, when a user performs an operation to end use of image forming apparatus 1, control unit 11 determines that the start timing has arrived. When control unit 11 determines that the start timing has arrived (S11: Yes), it shifts the process to step S12. Control unit 11 waits until the start timing arrives (S11: No).

[0040] <Step S12> In step S12, the control unit 11 (setting processing unit 113) sets the erase mode of the Secure Erase command to the Enhanced Erase mode.

[0041] <Step S13> In step S13, the control unit 11 (erasure processing unit 114) erases data in the entire storage area of ​​the HDD 171 in Enhanced Erase mode. That is, the control unit 11 erases data in all sectors of the HDD 171 (see FIG. 5). As a result, the entire storage area of ​​the HDD 171 becomes unused sectors.

[0042] <Step S14> In step S14, the control unit 11 determines whether or not a startup instruction has been acquired. For example, the control unit 11 acquires a startup instruction when the power supply of the image forming apparatus 1 is turned on. When the control unit 11 acquires the startup instruction (S14: Yes), the control unit 11 shifts the process to step S15. The control unit 11 waits until the startup instruction is acquired (S14: No).

[0043] <Step S15> In step S15, the control unit 11 (setting processing unit 113) formats only a portion of the total storage area of ​​the HDD 171. This makes the formatted portion of the storage area available for use. That is, the control unit 11 sets only a portion of the total storage area of ​​the HDD 171 as an available area (see FIG. 6).

[0044] When a portion of the storage area is formatted and becomes available, copy settings are restricted, and jobs that can be saved are restricted. In this manner, the image forming apparatus 1 becomes available with some functions restricted. The control unit 11 (execution processing unit 112) executes a function corresponding to the available area in the image forming apparatus 1. FIG. 7 shows the state (used sectors) of the available area in the HDD 171. Step S15 is an example of the setting step and execution step of the present invention.

[0045] <Step S16> In step S16, control unit 11 determines whether or not the start timing for starting the process of erasing data recorded in HDD 171 has arrived. For example, when the user performs an operation to end use of image forming apparatus 1, control unit 11 determines that the start timing has arrived. When control unit 11 determines that the start timing has arrived (S16: Yes), it shifts the process to step S17. Control unit 11 waits while executing the accepted job until the start timing arrives (S16: No).

[0046] <Step S17> In step S17, the control unit 11 sets the erase mode of the Secure Erase command to the Normal Erase mode.

[0047] <Step S18> In step S18, the control unit 11 (erasure processing unit 114) erases only data in used sectors of the entire storage area of ​​the HDD 171 in the Normal Erase mode. For example, as shown in Fig. 8, the control unit 11 erases data in used sectors of the usable area. As a result, the entire storage area of ​​the HDD 171 becomes unused sectors. Step S18 is an example of an erasure step of the present invention.

[0048] In this way, the control unit 11 executes the data erasure process each time the use of the image forming apparatus 1 is terminated. Specifically, the control unit 11 (erasure processing unit 114) issues a Secure Erase command and erases data in the available area using the Normal Erase mode and the Enhanced Erase mode. For example, the erasure processing unit 114 erases data in the entire storage area of ​​the HDD 171 in the Enhanced Erase mode (see FIG. 5), and the setting processing unit 113 sets the available area after the erasure processing unit 114 erases data in the entire storage area of ​​the HDD 171 (see FIG. 6). Then, the erasure processing unit 114 erases data recorded in the available area set by the setting processing unit 113 (see FIG. 7) in the Normal Erase mode (see FIG. 8).

[0049] As described above, when executing the Secure Erase command for the HDD 171 in the image forming apparatus 1, the control unit 11 uses the Normal Erase mode and the Enhanced Erase mode to shorten the execution time of the Secure Erase command during the user's work hours. For example, the control unit 11 executes the data erasure process in the time-consuming Enhanced Erase mode on the previous day (or on the weekend) (see FIG. 5). Then, on the next day (or the following week), the control unit 11 formats only a part of the storage area of ​​the HDD 171, starts it up, and the image forming apparatus 1 becomes available with limited functions (see FIG. 6). After using the image forming apparatus 1, the control unit 11 asks the user to execute the data erasure process in the Normal Erase mode (see FIG. 8). As a result, the data erasure process can be completed in a short time because the storage area used is small.

[0050] Furthermore, with the above configuration, for example, after the first data erasure process in Enhanced Erase mode, the image forming apparatus 1 can be used with limited functions. Also, the time required for the second data erasure process in Normal Erase mode can be shortened. Therefore, the data erasure process can be executed without the user having to leave the device for a long period of time.

[0051] As another embodiment, the control unit 11 may set a format capacity (formatting size) corresponding to the available area. Specifically, the control unit 11 may set the format capacity (available area) of the HDD 171 (see FIG. 6) according to a user operation. For example, as shown in FIG. 9, the user may be able to set the available area. In this way, by controlling (adjusting) the format capacity (format size) of the HDD 171, it is possible to adjust (variable) the Secure Erase time (data erasure time) in the Normal Erase mode. That is, the time for the second data erasure process in the Normal Erase mode can be varied by setting.

[0052] Furthermore, the control unit 11 may set the size (usable area) to be formatted in accordance with a setting operation for the execution time (erasure time) of the data erasure process. For example, the user sets the erasure time to an arbitrary time (maximum time) on the setting screen D1 shown in FIG. 10, and the control unit 11 sets the storage area according to the set time as the format size (usable area). In this way, the user can adjust (variably) the format capacity (format size) of the HDD 171 by specifying the Secure Erase time (data erasure time) in the Normal Erase mode. In other words, the user can specify in advance the time that he or she is able to wait.

[0053] Furthermore, as shown in Fig. 11, when the control unit 11 sets the Secure Erase time (maximum time), it may display the functions to be restricted. Furthermore, when the user selects a function to be restricted, the control unit 11 may vary the final overwrite erasure time. That is, the setting processing unit 113 sets the data erasure time in the Normal Erase mode by the user selecting a function to be restricted in the image forming apparatus 1. In this way, the user can adjust (variably) the Secure Erase time (data erasure time) in the Normal Erase mode by selecting (adjusting) a function to be restricted.

[0054] In the above embodiment, the Secure Erase command is given as a method for erasing data, but the control unit 11 may execute other erasure methods.

[0055] For example, as shown in Fig. 12, HDD 171 may be used with the storage area divided for each function. Here, the storage area of ​​HDD 171 is divided into a plurality of storage areas corresponding to each function of copy, print, save, and setting. When control unit 11 starts the data erasure process, first, it executes the overwrite erasure process for each storage area.

[0056] 13, the control unit 11 formats only a portion of the entire storage area of ​​the HDD 171. This makes the formatted portion of the storage area available for use. In other words, the control unit 11 sets only a portion of the entire storage area of ​​the HDD 171 as an available area.

[0057] When a portion of the storage area is formatted and becomes available, copy settings are restricted, and jobs that can be saved are restricted. In this manner, the image forming apparatus 1 becomes available with some of its functions restricted. Figure 14 shows the state (used sectors) of the available area in HDD 171.

[0058] 15, when the user performs an operation to end use of the image forming apparatus 1, the control unit 11 executes the overwrite erasure process again. That is, the control unit 11 erases the data in the used sectors of the usable area. Since the memory area to be erased is small, the overwrite erasure process is completed in a short time.

[0059] As described above, the overwrite erasure method can also complete the data erasure process in a short time, similar to the erasure method using the Secure Erase command.

[0060] As described above, the image forming device 1 according to this embodiment has a configuration in which, after all data in the storage area of ​​the data storage device (HDD 171) in the image forming device 1 is erased, a part of the storage area is formatted to set the part of the storage area as an available area, a function corresponding to the available area is executed in the image forming device 1, and data recorded in the available area by executing the function is erased. Thus, with the above configuration, it becomes possible to erase data recorded in the image forming device 1 in a short time while maintaining confidentiality.

[0061] [Disclosure Note] The following will provide an outline of the disclosure extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined in any desired manner.

[0062] <Appendix 1> a setting processing unit that formats a part of a storage area of ​​a data storage device in the image forming apparatus and sets the part of the storage area as a usable area after all data in the storage area is erased; an execution processing unit that executes a function corresponding to the available area in the image forming apparatus; an erasure processing unit that erases data recorded in the available area by executing the function; An image forming apparatus comprising:

[0063] <Appendix 2> the erasure processing unit issues a Secure Erase command and erases data in the available area using a Normal Erase mode and an Enhanced Erase mode; 2. The image forming apparatus according to claim 1.

[0064] <Appendix 3> the erasure processing unit erases all data in the storage area in the Enhanced Erase mode; the setting processing unit sets the available area after all data in the storage area is erased by the erasure processing unit, the erasure processing unit further erases the data recorded in the available area set by the setting processing unit in the Normal Erase mode. 3. The image forming apparatus according to claim 2.

[0065] <Appendix 4> the setting processing unit sets a format capacity corresponding to the available area. 4. The image forming apparatus according to claim 1,

[0066] <Appendix 5> the setting processing unit sets the format capacity in response to a user operation. 5. The image forming apparatus according to claim 4.

[0067] <Appendix 6> the setting processing unit sets a format capacity corresponding to the available area by a user specifying a data erasure time in the Normal Erase mode. 4. The image forming apparatus according to claim 3.

[0068] <Appendix 7> the setting processing unit sets a data erasure time in the Normal Erase mode by a user selecting a function to be restricted in the image forming apparatus. 4. The image forming apparatus according to claim 3.

[0069] <Appendix 8> After all data in a storage area of ​​a storage device in an image forming apparatus is erased, a part of the storage area is formatted and the part of the storage area is set as a usable area. executing a function corresponding to the available area in the image forming device; erasing data recorded in the available area by executing the function; and A data erasure method executed by one or more processors.

[0070] <Appendix 9> After all data in a storage area of ​​a storage device in an image forming apparatus is erased, a part of the storage area is formatted and the part of the storage area is set as a usable area. executing a function corresponding to the available area in the image forming device; erasing data recorded in the available area by executing the function; and A data erasure program for causing one or more processors to execute the above. [Explanation of symbols]

[0071] 1: Image forming device 11: Control section 12: Operation display section 14: Image reading unit 15: Image forming section 16: Communication I / F 17: Storage section 111: Reception department 112: Execution processing unit 113: Setting processing section 114: Erasing processing unit 171: HDD D1: Setting screen

Claims

1. a setting processing unit that formats a part of a storage area of ​​a data storage device in the image forming apparatus and sets the part of the storage area as a usable area after all data in the storage area is erased; an execution processing unit that executes a function corresponding to the available area in the image forming apparatus; an erasure processing unit that erases data recorded in the available area by executing the function; An image forming apparatus comprising:

2. the erasure processing unit issues a Secure Erase command and erases data in the available area using a Normal Erase mode and an Enhanced Erase mode; The image forming apparatus according to claim 1 .

3. the erasure processing unit erases all data in the storage area in the Enhanced Erase mode; the setting processing unit sets the available area after all data in the storage area is erased by the erasure processing unit, the erasure processing unit further erases the data recorded in the available area set by the setting processing unit in the Normal Erase mode. The image forming apparatus according to claim 2 .

4. the setting processing unit sets a format capacity corresponding to the available area. The image forming apparatus according to claim 1 .

5. the setting processing unit sets the format capacity in response to a user operation. The image forming apparatus according to claim 4 .

6. the setting processing unit sets a format capacity corresponding to the available area by a user specifying a data erasure time in the Normal Erase mode. The image forming apparatus according to claim 3 .

7. the setting processing unit sets a data erasure time in the Normal Erase mode by a user selecting a function to be restricted in the image forming apparatus. The image forming apparatus according to claim 3 .

8. a setting step of formatting a part of the storage area of ​​the storage device in the image forming apparatus after all data in the storage area is erased, and setting the part of the storage area as a usable area; an execution step of executing a function corresponding to the available area in the image forming device; an erasing step of erasing data recorded in the usable area by executing the function; Data erasure methods, including:

Images