JP2011086126A - Data transmission and copy guard method realized with human/machine interface device by mass storage class specification - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To take into account the problem of compatibility of a system, and to prevent data from being sneak looked at and stolen intentionally by a third person, when a human/machine interface device performs data transmission. <P>SOLUTION: In a data transmission and copy guard method of a human/machine interface device, the human/machine interface device is connected to a computer by mass storage class as an external USB storage device so as to encrypt data to be transmitted by a dynamic password, when data are transmitted, and to prevent the data from being written in a file allocation table. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a human machine interface apparatus, and more particularly to a data copy guard method applied to a human machine interface apparatus.

Human Machine Interface (HMI) device, or HID (Human-machine Interface Device), is an intermediate medium for exchanging information, communication and interactive work between users and devices It is. Users can input commands using the control keys on the human-machine interface device or touch-type icons on the monitor, so that these devices can respond to the commands entered by the user. Convenience and practicality when a user operates the device. Thus, human-machine interface devices are not only becoming more convenient in industrial automation control realization, but are gradually replacing traditional control panels that require a large amount of wiring.

As shown in FIG. 1, the human machine interface device 1 is mainly connected to a programmable logic controller (PLC), and a plurality of external devices 3 are connected via the programmable logic controller 2. A control command is sent to the mobile terminal and work data returned from the external device 3 is received. Many of the human-machine interface devices 1 that are currently in practical use are displayed on an external touch-type liquid crystal display (LCD) mainly by the control software attached to the inside thereof. The user can easily perform a touch operation to send work commands to these external devices 3 and acquire corresponding work data based on the work performed by these external devices 3. By the way, in order to cope with the development speed of industrial technology, it is necessary to periodically download new versions of these software to keep the human machine interface device 1 in the best condition. Furthermore, the data acquired by these human machine interface devices 1 needs to be uploaded periodically for the convenience of the user to further record and save.

However, as shown in FIG. 1, the human machine interface device 1 must be connected to an external computer 4 to upload and download data, and the connected computer 4 A driver program created by the manufacturer of the human machine interface device 1 is required. However, as the progress of information is accelerating, the operating system (Operating System, OS) has been rapidly updated, and the types are also diverse. Therefore, when connected to the computer 4, the human machine interface device 1 and the operating system of the connected external computer 4 are not compatible, and there is a problem that the driver program does not support, The human machine interface device 1 cannot be smoothly connected to the external computer 4 and consequently cannot transmit data. Thus, the manufacturer of the human machine interface apparatus 1 has to develop corresponding driver programs for different operating systems, which consumes considerable costs and time.

In addition to the direct connection method as described above, an external USB flash memory (USB Flash Disc, UFD) is used as a data transmission medium for some of the human-machine interface devices that have been put into practical use. And can support data exchange between a human-machine interface device and a computer. However, there are currently problems with computer viruses, and it is difficult to protect against the infection of viruses during the transmission of important data. In some cases, data can be stolen by hackers. This situation can be overlooked by traders.

In view of the above disadvantages, when the human-machine interface device performs data transmission, not only does it not take into account the compatibility problem of the system, but more seriously it is intentionally stolen, which is enormous for developers. There is a need to provide new data transmission systems in the market that do not incur losses.

The main object of the present invention is to connect a human machine interface device and an external computer in accordance with the mass storage class standard, so that a driver program for the human machine interface device is not installed in the external computer. According to the rules of the mass storage class standard, a human-machine interface device is built in the mass storage class standard that constructs a protection configuration when sending and receiving data to and from each other and prevents data from being stolen by a third party. A data transmission and copy guard method is provided.

In order to achieve the above object, according to the present invention, the human machine interface device is connected to a computer by a mass storage class as an external USB storage device, so that the operating system used by the computer and the human machine It is no longer necessary to newly install a driver program due to incompatibility with the interface device, and at the time of data transmission, the data to be transmitted is encrypted with a dynamic password, and the data is stored in the file allocation table. Does not actually write to.

The effect of the present invention over the prior art is that the computer operating system is not supported by the driver program of the human machine interface device when the human machine interface device and the external computer are connected. In addition, there is no snooping or misappropriation by third parties during data transmission.

FIG. 2 is a schematic diagram of a connection for use of a human machine interface device. FIG. 2 is a schematic diagram of a transmission connection of a human machine interface device. FIG. 6 is a schematic diagram of another transmission connection of a human machine interface device. It is the schematic of the memory | storage device using a mass storage class. 4 is a flowchart of file transmission in a preferred embodiment of the present invention. 4 is a flowchart of file download in a preferred embodiment of the present invention. 4 is a flowchart of file upload in a preferred embodiment of the present invention. FIG. 3 is a schematic diagram of a copy guard function in a preferred embodiment of the present invention.

A detailed description will be given here with reference to the preferred embodiments of the present invention.
First, please refer to FIG. 2A and FIG. 2B. This is a schematic diagram of the transmission connection of the human machine interface device of the preferred embodiment of the present invention. As shown in the figure, human-machine interface device 5 (Human-machine Interface Device, HID) is connected to an external computer 4 ′ via a USB (Universal Serial Bus) port 51 or 52. In the present invention, the HID 5 is mainly defined by the USB mass storage class (MSC) standard, so that the HID 5 is a pseudo external USB storage device 5 ′ (for example, an external memory drive in FIG. 3). ) As described above, since the HID5 has a plug-and-play effect according to the USB MSC standard, the HID5 can be installed in the external computer 4 ′ without installing a driver program developed by the HID5 manufacturer. You can connect at any time.

When the HID 5 and the external computer 4 ′ are connected to each other, the external computer 4 ′ sends an inquiry command to inquire about what device is connected, and the HID 5 is based on the USB MSC standard. A response is returned to the external computer 4 ′. Those skilled in the art of the present invention will recognize that these responses should be in a hard drive file system (File System, F / S) using the MSC standard, such as a master boot record (MBR). It is well known that information such as a file allocation table (FAT) is included. When the external computer 4 ′ receives these responses, the HID 5 connected to the external computer 4 ′ is found to be a USB storage device 5 ′ using the MSC standard, and the HID 5 is given, for example, “D: ¥” or A drive number such as “E: ¥” is given. However, the HID 5 of the present invention is already set at the time of shipment from the factory, and when connected to the external computer 4 ′, data transmission software 41 (mainly developed by the manufacturer) installed in the external computer 4 ′. The data transmission software 41) is used only when a file related to the HID (for example, an HID update file or an HID work record file) is transmitted to the HID5. Therefore, if data transmission is performed without using the data transmission software 41 or a file not related to the HID5 is transmitted, the HID5 cannot be accessed.

As shown in FIG. 3, the external computer 4 'uses the HID 5 of the present invention as the external USB storage device 5'. The main operation of the USB storage device 5 ′ is to cause the file system 53 to associate the file name of the file stored in the USB storage device 5 ′ with a specific FAT 54. Subsequently, according to the contents of the FAT 54, these files 55 correspond to the addresses of the entities stored in the USB storage device 5 ′, so that the external computer 4 ′ newly creates, modifies, and deletes work. To be able to Therefore, a general user can confirm on the external computer 4 ′ that the contents of the USB storage device 5 ′ correspond to the FAT 54. If these files 55 are certainly stored in the USB storage device 5 ′, but the corresponding data is not written in the FAT 54, the user cannot know this, and the external computer You cannot see these files 55 on 4 '. On the other hand, in the present invention, data transmission is protected by the characteristics used in the above-mentioned MSC standard. Details will be described below.

Please refer to FIG. This is a flowchart of file transmission in the preferred embodiment of the present invention. First, the data transmission software 41 installed in the external computer 4 'transmits a password file containing a dynamic password to the HID 5 and sends a request command to the HID 5 (step S40). In the HID 5, after the password file is received, the password file is surely received smoothly, but the corresponding data of the password file is not written in the FAT 54, so that the external computer 4 ′ is not connected to the USB storage device 5. The password file cannot be viewed from the contents of '. Therefore, since the third party can know the password file from the external computer 4 'and cannot search or steal it, the dynamic password cannot be acquired. Among these, the dynamic password can be generated by a combination of the external computer 4 ′ and the HID 5. For example, the external computer 4 ′ obtains a serial number of the HID 5 and calculates an arithmetic expression (eg, hash Function) can generate a dynamic password. Since the HID 5 itself also knows its own serial number, it is possible to generate the same dynamic password and encrypt / decrypt the upload / download file using the same arithmetic expression. However, this is only one preferred embodiment and is not limited to this. Subsequently, the HID 5 determines what the request command sent by the external computer 4 'is (step S42), that is, determines whether to download a file or upload a file.

After step S42, the external computer 4 'transmits the file with the HID 5 by the data transmission software 41 (step S44). If it is determined in step S42 that the request command is a file download request, the HID 5 at this time receives the data download file transmitted from the external computer 4 ′, and the data download file Encrypted with a dynamic password. Then, after the HID 5 actually receives the data download file, it is not written to the FAT 54. Therefore, the external computer 4 'cannot see the data download file from the contents of the USB storage device 5'. On the other hand, if the request command is a file upload request in step S42, the HID 5 writes the corresponding data of the existing data upload file in the HID 5 in the FAT 54, so that the external computer 4 The user can view the data upload file from the contents of the USB storage device 5, and then the data transmission software 41 copies the data upload file to the external computer 4 ′ to complete the upload operation. Of these, the data upload file is encrypted with a dynamic password. Then, after the HID 5 completes the upload operation, the data upload file is immediately deleted from the FAT 54 so that the upload file cannot be copied separately by a third party. Finally, after the transmission of the file is completed, the HID 5 or the external computer 4 ′ uses the generated dynamic password to decrypt the downloaded or uploaded file according to the calculation formula ( In step S46), necessary data is acquired, and subsequent operation work is performed.

Then, in step S42 for determining the request command, it is confirmed what command is requested using the file name of the password file. For example, in step S40, if the file name of the password file is “Download.dat”, after the HID 5 is received, the operation that the external computer 4 ′ wants to perform by the data transmission software 41 is file download. I understand. On the other hand, if the file name of the password file is “Upload.dat”, it can be understood that the operation desired by the external computer 4 ′ is file upload. However, this is only one preferred embodiment, and those skilled in the art of the present invention can determine the file name setting by the programmer and use some special symbols. Moreover, there is no fixed setting rule, and this should not limit the patent scope of the present invention.

The file work procedure in FIG. 4 can be further divided into a file download flowchart and a file upload flowchart, and can be described in more detail. As shown in FIG. 5, this is a file download flowchart in the preferred embodiment of the present invention. First, the external computer 4 'transmits a download password file including the dynamic password in the contents to the HID 5 by the installed data transmission software 41 (step S50). Since the HID 5 is not written in the FAT 54 even after receiving the download password file, the external computer 4 ′ can determine whether the transmission of the download password is successful from the contents of the USB storage device 5 ′. In addition, a third party cannot obtain the download password file. Subsequently, if the dynamic password in the download password file is correct, the HID 5 stores information indicating that the external computer 4 'has received the download password file and is waiting for a file download operation. I need to reply. That is, the password confirmation file is written in the FAT 54 (step S52), and the file name of the password confirmation file has a reply presentation effect such as “get.dat” or “wait.dat”. The password confirmation file is generated in the contents of the USB storage device 5 ′ in the external computer 4 ′, and the external computer 4 ′ confirms the password confirmation file by the data transmission software 41 and then the download password file. Since it can be determined that the transmission has already been successful, data transmission can be performed in the next step.

After step S52, the external computer 4 ′ transmits the data download file to the HID 5 by the data transmission software 41 (step S54). After the HID 5 is received, the external computer 4 ′ is also used to prevent theft by a third party. It is not written in the FAT54. Of these, the data download file is encrypted with the dynamic password by the external computer 4 '. As in step S52, after the data download file has been reliably received, the data confirmation file is written in the FAT 54 (step S56), and the file name of the data confirmation file is set to, for example, “down.dat” or Provide a reply presentation effect such as “ok.dat”. The external computer 4 'can determine that the transmission of the data download file has been completed after searching for the data confirmation file from the contents of the USB storage device 5'. Finally, the HID 5 uses the dynamic password in the download password file, and decrypts the data download file according to the calculation formula (step S58). Of these, the purpose of the password confirmation file and the data confirmation file is to simply send back to the external computer 4 'information indicating that the HID 5 has received the file. Since it has no significance or content, even if the two files are written in the FAT 54 and stolen by a third party, it does not cause any adverse effects on data transmission.

Still referring to FIG. This is a file upload flowchart in the preferred embodiment of the present invention. First, as in step S50 in FIG. 5, the external computer 4 'transmits an upload password file including the dynamic password to the HID 5 by the installed data transmission software 41 (step S60). Subsequently, when the HID 5 receives the upload password file, the external computer 4 ′ can confirm that the data transmission software 41 wants to upload the file. Therefore, after confirming that the dynamic password in the upload password file is correct, the HID 5 writes the data upload file that the external computer 4 'wants to acquire into the FAT 54 (step S62). Of these, the data upload file is encrypted with the dynamic password via the HID 5 and is already in the HID 5 but not written in the FAT 54. Therefore, before the step S62, the external computer 4 'cannot see the data upload file from the contents of the USB storage device 5'. After step S62, the external computer 4 ′ can view the data upload file from the contents of the USB storage device 5 ′. As a result, the data transmission software 41 converts the data upload file into the external computer 4 ′. Will be copied inside.

Further, it should be noted that when the data upload file is copied, the HID 5 activates a copy guard function in cooperation with the data transmission software 41, so that the copy operation of the external computer 4 ′ is valid. This is to determine whether or not (step S64). If it is determined that the copying operation of the external computer 4 'is valid, the HID 5 allows the external computer 4' to copy the data upload file by the data transmission software 41 (step S66). Further, after the copy is completed, the data upload file is deleted from the FAT 54 (step S68). On the other hand, if it is determined in step S64 that the copying operation is not valid or not performed by the data transmission software 41, copying of the data upload file is not permitted. The process directly proceeds to step S68, and the data upload file is immediately deleted from the FAT 54. Finally, the HID 5 uses the dynamic password in the upload password file, decrypts the encryption of the data upload file by the arithmetic expression (step S70), and operates.

The copy guard function described above is as shown in FIG. This is a schematic diagram of the copy guard function in the preferred embodiment of the present invention. When the HID 5 writes the data upload file to the FAT 54 and displays the data upload file in the contents of the USB storage device 5 ′, a plurality of alternative files are generated with random numbers by the dynamic password and the arithmetic expression. At the same time, the plurality of alternative files and the data upload file are changed to random file names having no meaning such as “AEJAE4GHA.dat” or “1R5JGH6FB.dat” as shown in FIG. After the external computer 4 ′ confirms these files based on the contents of the USB storage device 5 ′, the external computer 4 ′ calculates what the exact file name of the data upload file is based on the same dynamic password and the arithmetic expression. Perform a legitimate copy operation. Therefore, when a copy of the substitute file with a file name error is requested, the HID 5 determines that a third party is attempting to obtain the file, and therefore deletes all files from the FAT 54. In this way, file theft by a third party can be interrupted. Even if a third party accidentally guesses what the correct file is, and even if the copy succeeds, it will be disguised as a meaningless file name if there is no calculation using the dynamic password and the arithmetic expression. Since the data upload file being encrypted cannot be decrypted correctly, it still has a high copy guard function.

The foregoing is merely a preferred embodiment of the present invention and is not intended to limit the patent scope of the present invention. Therefore, any equivalent modifications made using the content of the present invention are of course within the scope of the present invention. I state that it is included in.

Prior Art 1 Human Machine Interface Device 2 Programmable Logic Controller 3 External Device 4 Computer
Invention 4 'External Computer 41 Data Transmission Software 5 Human Machine Interface Device (HID)
5 'storage device 51, 52 USB port 53 file system 54 file allocation table (FAT)
55 Steps S40 to S46, S50 to S58, S60 to S70

Claims (19)

A human machine interface that uses a USB (Universal Serial Bus) mass storage class (MSC) standard to make the human machine interface device a pseudo USB storage device, and transmits data to and from an external computer. A data transmission and copy guard method implemented by the interface device in the mass storage class standard,
a) the human machine interface device receiving the transmitted password file and request command;
b) the human machine interface device determining what the request command is;
c) transmitting a data file based on the request command;
d) after step c, decrypting the file with a dynamic password described in the password file;
The human machine interface device does not write the received password file in a file allocation table (FAT) so that the external computer cannot know the existence of the password file. Data transmission and copy guard method realized by mass storage class standard by a human machine interface device. 2. The data transmission and copy guard method according to claim 1, wherein the request command is represented by a file name of the password file. If it is determined in step b that the request command is a file download request, in step c, the data download file transmitted from the external computer and encrypted with the dynamic password is stored in the human machine interface. The data transmission and copy guard method according to claim 2, wherein the apparatus receives the data. The human machine interface device does not write in the file allocation table after the human machine interface device receives the data download file so that the external computer cannot know the existence of the data download file. 4. The data transmission and copy guard method according to 3. If it is determined in step b that the request command is a file upload request, step c includes
c1) In order to prevent the external computer from knowing the existence of the data upload file, the human machine interface device stores the data upload file stored therein and encrypted by the dynamic password, Writing into the file allocation table;
c2) after step c1, if the copy operation is valid, the human machine interface device authorizes copying of the data upload file;
3. The data transmission and copy guard method according to claim 2, further comprising the step of: c3) a human machine interface device deleting the data upload file after step c2. In step c1, after processing by the copy guard function, the step of further writing the data upload file into the file allocation table includes:
c11) generating a random number file name of the data upload file by an arithmetic expression based on a dynamic password described in the password file;
c12) generating a plurality of alternative files having a random number file name by an arithmetic expression based on the dynamic password described in the password file;
6. The data transmission and copy guard method according to claim 5, further comprising the step of: c13) writing the data upload file and a plurality of alternative files together in the file allocation table. 7. The data transmission and copy guard method according to claim 6, wherein when the copy of the plurality of alternative files is requested in step c2, the copy operation is regarded as invalid. 8. The data upload file according to claim 7, wherein the data upload file is deleted from the file allocation table when the data upload file is copied once or when a copy operation is not valid in the step c3. Data transmission and copy guard method. The data transmission and copy guard method according to claim 6, wherein the arithmetic expression is an arithmetic expression of a hash method. The human machine interface device, which is the pseudo USB storage device, uses the data transmission software developed by the manufacturer of the human machine interface device to create a data file related to the human machine interface device. 2. The data transmission and copy guard method according to claim 1, wherein smooth data transmission with the external computer is possible only when the data is transmitted. A human machine interface that uses a USB (Universal Serial Bus) mass storage class (MSC) standard to make the human machine interface device a pseudo USB storage device, and transmits data to and from an external computer. A data transmission and copy guard method implemented by the interface device in the mass storage class standard,
a) the human machine interface device receiving the transmitted password file;
b) If the password file is a download password file, the human machine interface device confirms that the dynamic password in the download password file is correct, and then stores the password confirmation file in a file allocation table (File Allocation Table, Writing during FAT);
c) after step b, the human machine interface device receives the data download file transmitted and encrypted with the dynamic password;
d) If the password file is an upload password file, the human-machine interface device has a dynamic password in the upload password file so that the external computer cannot know the existence of the data upload file. Writing the data upload file encrypted with the dynamic password into a file allocation table after confirming that it is correct;
e) after step d, if the copy operation is valid, the human machine interface device authorizes copying of the data upload file;
f) after step e, the human machine interface device deleting the data upload file;
The human machine interface device does not write the received password file and the data download file in the file allocation table so that the external computer cannot know the existence of the password file and the data download file. A data transmission and copy guard method realized by a mass storage class standard by a human-machine interface device characterized by the above. The method further comprises the step of: g) decrypting the data download file or the data upload file with a dynamic password described in the password file after step c or step e. The data transmission and copy guard method described in 1. 12. The method of claim 11, wherein, in the step c, after the external computer generates the password confirmation file in the file allocation table, the data download file is transmitted to the human machine interface device. Data transmission and copy guard method. h) after step c, the human machine interface device writes a data verification file into the file allocation table in order to return information that the external computer has received the data download file; 14. The data transmission and copy guard method according to claim 13, further comprising: In step d, after processing by the copy guard function, further writing the data upload file into the file allocation table,
d1) generating a random number file name of the data upload file by an arithmetic expression based on the dynamic password described in the password file;
d2) generating a plurality of alternative files having a random number file name by an arithmetic expression based on the dynamic password described in the password file;
6. The data transmission and copy guard method according to claim 5, further comprising the step of: d3) writing both the data upload file and a plurality of alternative files into the file allocation table. 16. The data transmission and copy guard method according to claim 15, wherein when the copying of the plurality of alternative files is requested in the step e, the copying operation is regarded as invalid. The method of claim 16, wherein in the step e, the data upload file is deleted from the file allocation table when the data upload file is copied once or when a copy operation is not valid. Data transmission and copy guard method. 16. The data transmission and copy guard method according to claim 15, wherein the arithmetic expression is an arithmetic expression of a hash method. The human machine interface device, which is the pseudo USB storage device, uses the data transmission software developed by the manufacturer of the human machine interface device to create a data file related to the human machine interface device. 12. The data transmission and copy guard method according to claim 11, wherein smooth data transmission with the external computer is possible only during transmission.

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