JP2001016664A - Control display device and recording medium recording its program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a control display device that can easily build up a large- scale control system and reject at illegal access. SOLUTION: Each graphic control panel 5 or a control host computer 7 makes inter-communication with a PLC 3 independently of its model with a prescribed common protocol via another communication network 6 than that of an exclusive network 4 to which the PLC 3 is connected. Each graphic control panel 5 relays communication in both networks 4, 6 as required. When a remote network device 8 of the common network 6 is remotely connected to each graphic control panel 5, each graphic control panel 5 refers to authentication data storage section 57 to authenticate the unit 8 and registers only the unit 8 whose authentication is successible to participation station information of a participation station storage section 58. Moreover, when each graphic control panel 5 is accessed, each graphic control panel 5 rejects an access from the unit 8 not registered in the participation station information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system including a control device that communicates according to a model-specific communication protocol, and a control display device that exchanges data with the control device. The present invention relates to a control display device in which a control system can be easily constructed and an unauthorized access can be refused, and a recording medium on which the program is recorded.

[0002]

2. Description of the Related Art Conventionally, programmable logic
The controller (hereinafter abbreviated as PLC) is, for example,
It is widely used as a control device for controlling various target systems such as a belt conveyor type automatic assembling machine. Further, in recent years, with the complexity of the target system, a plurality of PLCs have been used in cooperation with each other. In addition, the display of data from each PLC or the control instruction to the PLC is performed not only by the control display devices arranged near the PLC, but also by, for example, the remote control display devices. In some cases, a control system is constructed so that a control host computer installed at a location can display or operate the computer.

Specifically, for example, as shown in FIG.
In the conventional control system 501, the PLC 503 is positioned as the center of control, and each PLC 503 includes:
A control target device 521a and a sensor 521b of the target system 502 are connected to a control display device 505 for performing display and control instructions. Further, the PLC 5
03, the other PLC 503 and the control host computer 507 are directly connected via a predetermined interface circuit.
Alternatively, the PLC 503 and the control host computer 507 are connected indirectly via a dedicated adapter.
The transfer of control data between the PLC 503 and each PLC 503 is performed using the communication function of the PLC 503.

However, the control system 5 having the above configuration
01, between the PLC 503 and the control host computer 507 and between the PLC 503 and the control display device 5.
Since communication is performed using a communication protocol unique to the PLC 503 during the period between 05 and 05, there is a problem that it is difficult to mix many types of PLC 503.

[0005] Further, since most of the communication of the control system 501 is processed, the load on the PLC 503 increases. Furthermore, since it is necessary to prepare a communication protocol for communicating with the PLC 503 in both the control host computer 507 and the control display device 505, the control host computer 507 and the control display device 5
It takes time to manufacture and maintain 05.

More specifically, the PLC 503 has been developed from a sequencer using a relay, and is particularly good at processing related to I / O control such as switch on / off control and data acquisition from a sensor. Therefore, the ability to process most of the communication of the control system 501 as the center of data communication is often insufficient, and even if the processing can be performed, the burden is large. For example, if only controlling the target system 502, the PLC 503 usually requires a storage capacity of about several tens of kilobytes and a processing capacity corresponding to the storage capacity. It is difficult to process most of the communication at sufficient speed.

[0007] Further, since the PLC 503 has been developed from a sequencer, a communication protocol used for data communication is often different for each model of the PLC 503, such as for each manufacturing company or each product even in the same company. .
Therefore, conventionally, the same type of PLC 503 is often used in the control system 501.

[0008] Here, when the degree of the difference between the communication protocols is small, specifically, the communication protocols necessary for establishing the communication, such as the start character and the stop character, the method of designating the transmission / reception address, are the same, and , To the extent that only the less important commands differ
Of the functions of the PLC 503, it is not impossible to mix PLCs 503 of different models in the control system 501 unless functions that are actually used are restricted and different commands are used. However, for example, when important command differences such as commands for communicating with a plurality of models are different, the control host computer 507 and P
Even if communication is established with the LC 503, the control host computer 507 cannot instruct the PLC 503 to perform a desired operation.

When the communication protocol itself required for establishing the communication is different, not only communication between the PLC 503a having a different communication protocol and the control host computer 507 is not established, but also a common communication protocol is used. Communication between the PLC 503 and the control host computer 507 is hindered. Therefore, the P
When connecting the LC 503a, the converter 510 is inserted and the control host computer 507 or another PLC 5 is connected.
From 03, it is necessary to mutually convert communication protocols so that the PLC 503a looks like the same model. Here, in the control system 501, the place where the converter 510 can be installed is often limited, and when a new converter 510 is provided, the cost of the entire control system 501 increases. Furthermore, since there are a large number of communication protocols of the PLC 503, for example, 100 or more, a desired converter 510 is not always present.

[0010] As a result, when the PLC 503 is arranged at the center of communication, many types of PLCs are added to the control system 501.
It is difficult to mix C503, and the choices when selecting PLC503 are limited.

In addition, in the above-mentioned conventional control system 501, since both the control host computer 507 and the control display device 505 communicate with the PLC 503, both need to communicate using the communication protocol of each PLC 503. . Therefore, when the control host computer 507 and the control display device 505 are manufactured, a program for communicating with all the communication protocols of the PLC 503 that may be connected is provided by the control host computer 507 and the control display device 505. It is necessary to prepare for both. As a result, when manufacturing the control host computer 507 and the control display device 505, many PLCs 50 are used.
In order to deal with the third, an extremely large number of software man-hours are required. Further, when the PLC 503 that communicates with a new communication protocol is developed, it is necessary to newly prepare a program that communicates with the communication protocol in both the control host computer 507 and the control display device 505, which further reduces the trouble. Take it.

Here, in order to solve the above problem, the applicant of the present application has proposed a completely new control system in Japanese Patent Application No. 10-117117. In this control system 101, as shown in FIG. 10, a graphic operation panel 105 as a control display device and a PLC
A common network 106 is provided separately from the dedicated network 104 provided between the graphic operation panel 103 and each of the graphic operation panels 105. A predetermined common communication protocol (common protocol) is provided via the common network 106. Are communicating with each other. Each graphic operation panel 105 is connected to the common network 10.
6 and the communication on the dedicated network 104 are relayed as necessary. Thus, the control host computer 107 can transmit an instruction to the PLC 103 via the graphic operation panel 105 without any trouble,
Information from C103 can be obtained.

In this configuration, devices connected to the common network 106 communicate with each other using a predetermined common protocol irrespective of the dedicated protocol employed in the dedicated network 104.
C103 can be easily mixed in the same control system 101, and a large-scale control system having a large number of components can be realized relatively easily.

[0014]

However, when a large-scale control system is constructed by the above configuration, a new problem that security is difficult to maintain arises. Specifically, a conventional control system 501 shown in FIG.
Now, among the various dedicated protocols, the control system 50
If one does not understand the dedicated protocol employed in step 1, information cannot be obtained and the PLC 503 cannot be controlled. In addition, since the control system 501 is relatively small, the accessible points are limited to a manufacturing site or the like. Therefore, for example, unless a computer is brought to the manufacturing site, the devices of the control system 501 cannot be accessed.

In contrast, the configuration of the above-mentioned prior application filed by the present applicant, that is, the control system 10 shown in FIG.
For example, when the network device 108 is connected to the common network 106, if the network device 108 adopts the common protocol, the PLC 103 adopting any of the dedicated protocols can obtain information. , PLC103. In addition, the scale of the control system 101 increases, for example,
If a network is configured to be accessible from other manufacturing lines, other departments in the company, and even from outside the company, it becomes difficult to manage access points. Therefore, there is a risk that a third party may illegally access, for example, an application program or data in which the know-how of the user is condensed from a relatively easily accessible point, and the data may be stolen, falsified or destroyed. There is. Further, by the unauthorized access, the target system 10
There is also a risk that the second machine tool or the like malfunctions and human lives are threatened.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a control display device which can easily construct a large-scale control system and can reject unauthorized access. is there.

[0017]

According to a first aspect of the present invention, there is provided a control display device which is connected to itself by a dedicated protocol specific to a control device for controlling a control target device. In a control display device having a dedicated protocol interface for communicating with a control device and a display unit for displaying information on the control device or the device to be controlled, the following means are provided.

That is, a common protocol interface provided separately from the dedicated protocol interface and communicating with a predetermined common protocol, relay means for relaying communication with the dedicated protocol and communication with the common protocol, A participant device information storage unit that stores registered participant device information in which devices participating in the common protocol network, and, when remotely connected via the common protocol network, authenticates the connection source device and performs authentication. Authentication means for registering the device that succeeded in the participant information, and referring to the participant information storage means when access has been received, to determine whether or not the access source is registered in the participant information. Access rejecting means for rejecting access when the user is not registered.

In the above configuration, a common protocol interface is provided separately from the dedicated protocol interface. For example, devices connected to a common protocol network (common network), such as other control display devices and host computers, are provided. Communicate with each other using a common protocol regardless of the dedicated protocol of the control device. Further, the relay unit of the control display device relays communication using the common protocol and communication using the dedicated protocol by performing protocol conversion as necessary. This allows
Even if the dedicated protocol of the control device connected to the control display device is different for each control display device, each of the above devices exchanges information and control instructions of each control device and the control target device, for example. Communication can be performed without any trouble.

Here, the legitimate user connects a device capable of communicating with the common protocol to the network of the common protocol, and makes a remote connection by, for example, sending a login command to the control display device. On the other hand, when the control display device is remotely connected via the common network, the control display device is transmitted in response to an inquiry about the control display device, for example, a password transmitted at the same time as the login command, or after the login command. Authenticate the connection source device by using a password. here,
If the user is an authorized user, the authentication is successful, and the authentication unit of the control display device registers the device in the participating device information.

Thereafter, when the authorized user accesses the control display device using the above device, the device is registered in the participating device information. Access to the control display device is successful.

Conversely, if an unauthorized user connects a device to the common network and connects remotely,
Since the user is not an authorized user, the authentication by the authentication unit of the control display device fails. Therefore, the device of the unauthorized user is not registered in the participating device information of the control display device. In this case, even if an unauthorized user's device subsequently accesses the control display device, the device is not registered in the participating device information, and the access rejection unit rejects access from the device.

In the above configuration, since the control display device includes the relay unit, the control device and the control display device include:
Control devices having different communication protocols can be easily mixed in a control system including a host computer and the like as necessary. Therefore, it is possible to greatly reduce the labor required to add the control device to the control system as compared with the related art, and it is easy to construct a control system including, for example, a control device and the like, in which the number of constituent devices is larger.
Furthermore, since the control display device includes an authentication unit,
Even if an unauthorized user's device is connected to the common network, information on the control device and / or the device to be controlled is not sent to the device, and the control device does not receive an instruction from the device. As a result, a control system having a large scale and protected from unauthorized access can be constructed.

Further, the recording medium according to the invention of claim 2 is:
A recording medium storing a program for causing a computer having a first and second interface and a display unit different from each other to operate as a control display device,
In order to solve the above-mentioned problem, the following program is recorded.

That is, means for controlling the first interface to communicate with a control device connected to the first interface by means of a dedicated protocol specific to the control device for controlling the control target device. Means for controlling, means for communicating with a predetermined common protocol, means for controlling the display means, means for displaying information on the control device or device to be controlled, communication with the dedicated protocol and communication with the common protocol Means for relaying, when remote connection is made via the network of the common protocol, means for authenticating the connection source device, registering and registering the successfully authenticated device in the participation device information, and receiving access If the access source is not registered in the participant information, it is determined whether or not the access source is registered. As not to means, program for operating the computer is recorded.

When a program is read from the recording medium having the above configuration and executed by the computer, the computer operates as the control display device according to the first aspect. As a result, similarly to the first aspect, as a result, a control system having a large scale and protected from unauthorized access can be constructed.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention.
The following is a description based on FIG. That is, the control system according to the present embodiment controls a plurality of programmable logic controllers (hereinafter, abbreviated as PLCs) in cooperation with each other, for example, when the target system is a belt conveyor type automatic assembler. When controlling a target system that
A particularly preferred system, for example, FIG.
As shown in the figure, the target system (control target device) 2
(Control device) 3 connected to the PLC 3 via a dedicated network 4 that communicates with the PLC 3 using a communication protocol specific to the PLC 3. In many cases, the PLC 3 is connected to the target system 2 near the target system 2. A graphic operation panel (control display device) 5 operated by an operator, a common network 6 for connecting the graphic operation panels 5 with a common communication protocol, and a common network 6 A control host computer 7 for monitoring and controlling the entire control system 1 or setting the control system 1 from a location remote from the operation panel 5 is provided.

In the control system 1, unlike the related art, a graphic operation panel 5 is arranged at the center of communication, and the graphic operation panel 5 is connected to both the dedicated network 4 and the common network 6. . Further, when the communication protocols of the two networks 4 and 6 are different, the graphic operation panel 5 converts the two communication protocols to each other and connects the PLC 3 connected to itself.
And relay the communication between the control host computer 7 and another graphic operation panel 5. Thereby, the PLC 3 connected to each graphic operation panel 5
However, even if the communication protocols employed by each other are different from each other, the graphic operation panel 5 and the control host computer 7 can communicate using a common communication protocol.

More specifically, the target system 2 includes a control target device 21a, such as a valve and a motor, which performs an operation in accordance with an instruction, and a control target device 21a, such as a flow rate sensor and a temperature sensor, and a target device 21a. A sensor 21b for detecting the state of each part of the system 2 is provided, and the control target device 21a and the sensor 21b (hereinafter, collectively referred to as the device 21) are controlled by the PLC 3. Also, the PLC 3 has a unique communication protocol for each model of the PLC 3 such as, for example, each manufacturer or each product type, due to the history of development from the sequencer. Therefore, the PLC 3 is connected to the graphic operation panel 5 via the dedicated network 4, and communicates with the graphic operation panel 5 using a communication protocol that allows the PLC 3 to communicate.

Thus, the PLC 3 transmits the data acquired by the sensor 21b to the graphic operation panel 5 itself, or to another graphic operation panel 5 or the control host computer 7 via the graphic operation panel 5, and The control target device 21a can be controlled by receiving a control instruction transmitted from the graphic operation panel 5 itself or via the graphic operation panel 5.

The communication protocol in a broad sense includes, for example, codes indicating a start character and an end character, transmission / reception timing of each character, and a transmission source and a transmission destination such as a method of specifying a transmission destination and a transmission source. If the communication protocol cannot transmit data normally unless it is unified in the network, and if the transmission source and destination are not unified, for example, a command system that each PLC 3 can understand, one of the desired operations; There is a communication protocol that does not match the operation performed by the other and cannot be controlled normally.However, in the following, a combination of the two is referred to as a communication protocol. The latter is distinguished as a command system.

On the other hand, the graphic operation panel 5 has a dedicated network interface unit (dedicated and first protocol interface) 51 for communicating with the PLC 3 via the dedicated network 4, and a display unit (display means) for displaying information to workers. 52, an input unit 53 for receiving an instruction from a worker, and a data processing unit 54 for controlling the entire graphic operation panel 5 and processing data handled by the graphic operation panel 5. In the present embodiment, for example, a liquid crystal display device or the like is used as the display unit 52, and a touch panel integrally formed on the display screen of the display unit 52 is used as the input unit 53. In the following, various interface units such as the dedicated network interface unit 51 and a common network interface unit 55 to be described later are abbreviated as IF units.

Further, the graphic operation panel 5 includes a common network / IF unit (common and second protocol interface) 55 for connecting to the common network 6, a communication protocol of the common network 6 and a communication protocol of the dedicated network 4. And a protocol conversion storage unit 56 that stores information for mutually converting between the two. When the communication protocols of the two networks 4 and 6 are different from each other, the protocol conversion storage unit While referring to 56, one communication protocol is converted to the other. The data processing unit 54 and the protocol conversion storage unit 56 correspond to the relay unit described in the claims.

In the present embodiment, each of the units 51 to 58 described above and below is a storage unit itself such as a RAM, a ROM or a hard disk, or a functional block realized by a CPU executing a predetermined program. It can also be realized by hardware performing the same operation. However, when realized by software as in the present embodiment, each unit 51 to 58 can be easily realized only by distributing a recording medium on which a program is recorded and causing a computer to execute the medium.

Here, in the communication protocol specified by the manufacturer of each PLC 3, when data reading is instructed, a control code indicating that the next code to be transmitted is a command as shown in FIG. (ESC) and P
A command code (RD) for instructing the LC3 to read data, a read start address (X0001),
A data string 41 including a read size (5) and a control code (RET) indicating the end of transmission is transmitted. However, between the PLCs 3, the command system including the command code, of course, the order of addresses and sizes, and the like,
In many cases, the control code itself or the expression method for expressing an address or a size (such as a bit width for indicating a numerical value or a code type for indicating a character) are different from each other.

Accordingly, in the present embodiment, when the graphic operation panel 5 performs data communication via the common network 6, the graphic operation panel 5 can communicate with the unified communication protocol regardless of the communication protocol transmitted through the dedicated network 4. A communication protocol (common protocol) common to communication protocols that can be transmitted on the dedicated network 4 is defined.

Specifically, in the present embodiment, the common network 6 is an Ethernet (trademark: Xerox Corporation)
A local area network (LAN) is used, and TCP / IP is used as a transmission protocol in the common network 6. Therefore,
A unique IP address is assigned to each of the graphic operation panel 5 and the control host computer 7 connected to the common network 6, and when communicating via the common network 6, the format specified by TCP / IP That is, as shown in FIG. 3, a data string 61 in a format including a header section 62 including the IP address of the transmission source and the transmission destination and a data body 63 indicating the communication content is transmitted and received. Thus, for example, even when the network device 8 such as a control host computer used by the developer of the control system 1 is connected via a telephone line from a place different from the operating company of the control system 1, TC
Any communication device that can communicate by P / IP can freely participate in the common network 6 without hindering data transmission between other communication devices.

Further, in the common protocol, a common code 64 indicating the content of the command is included in the data body 63r when transmitting a command instructing data reading to the PLC 3.
And the related information 65 attached to the common code 64 includes a read start address 65a and a read size 65b. Further, the data body 63w at the time of instructing the data write includes the write start address 65c and the write data 65d as the related information 65.

The common code 64 is a command code (each PLC) in the dedicated network 4 between commands having the same contents among commands that can be understood by each PLC 3.
3 command code).
Further, for example, the order in which the data in the related information 65 is transmitted, such as the read start address 65a and the read size 65b, and the expression method at the time of transmission are unified irrespective of the communication protocol in the dedicated network 4. Thus, in the common protocol, the command to be executed can be uniquely specified regardless of the PLC 3 connected to the graphic operation panel 5.

Here, the information stored in the protocol conversion storage unit 56 shown in FIG. 1 may be in any format as long as the communication protocol of the dedicated network 4 and the common network 6 can be mutually converted. The protocol conversion storage unit 56 according to the embodiment includes a data transfer format FMT indicating a format of data transmitted on the dedicated network 4 and a command conversion table TBL indicating a correspondence relationship between command codes transmitted on both networks 4.6. And remember.

More specifically, as shown in FIG. 2, the data transfer format FMT includes, for example, data content to be read / written, data size, or , A skeleton-like data string in which a portion that changes depending on the data content to be actually transmitted, such as an address to be read or written, is undefined, and only the use is defined for the undefined portion. If the command area is undefined, and if the data transfer format FMT extracted from the data string actually transmitted becomes common among a plurality of commands, the command area is also undefined and these command Between them, a common data transfer format FMT may be used.

The command conversion table TBL includes:
As shown in FIG. 4, the correspondence between the common code transmitted on the common network 6 and the command code transmitted on the dedicated network 4 is stored, and the data processing unit 54 converts one code into the other code. Can be converted to code.

According to the above configuration, when the data sequence 61 of the common protocol is received via the common network 6, the data processing unit 54
Then, a common code 64 indicating a command to be transmitted to No. 3 and related information 65 are extracted. Further, the data processing unit 54 refers to the command conversion table TBL and selects a command code that can be transmitted through the dedicated network 4 and corresponds to the common code 64. If necessary, the expression method of the related information 65 is converted into an expression method transmitted by the dedicated network 4. As a result, when the command to be transmitted to the PLC 3, the data content itself, the data size and the address, and the like are determined, the data processing unit 54 can generate a data sequence to be transmitted to the PLC 3 by referring to the data transfer format FMT. On the other hand, when the data sequence 41 is received from the PLC 3, the data processing unit 54 extracts the command indicated by the data sequence, the data content itself, the data size and the address, etc. by applying the data sequence to the data transfer format FMT. Is converted into the data string 61 of the common protocol in the reverse procedure.

The combination (protocol information) of the data transfer format FMT and the command conversion table TBL is set in accordance with the communication protocol of the PLC 3 before the graphic operation panel 5 and the PLC 3 communicate control-related data. Is connected, the protocol information is switched. For example, in FIG.
When changing from PLC C3 to PLC B of model B, the command conversion table TBLa is used to convert the command
Is switched to.

The communication protocol may be selected by the user by operating the control host computer 7 or the graphic operation panel 5, for example. further,
While the graphic operation panel 5 sequentially selects communication protocols that can be sent by itself, the graphic operation panel 5 sends a command capable of specifying the communication protocol of the PLC 3 to the PLC 3, and
The communication protocol may be automatically determined based on the response code from. In addition, the graphic operation panel 5
The above protocol information may be stored for all the communication protocols adopted by the PLC 3 that can be connected to itself, or only the communication protocol of the currently connected PLC 3 may be stored, and if necessary, The program may be downloaded from the control host computer 7 or through a recording medium by various methods.

As described above, by generating the data string 41 to be transferred to and from the PLC 3 in real time during the operation of the control system 1, the graphic operation panel 5
Without asking where the input data came from, P
The data can be transferred to the LC 3, and even if the PLC 3 is changed, the control system 1 can respond immediately without stopping.

Here, the graphic operation panel 5 is an essential component of the control system 1. However, in recent years, in order to display a high-resolution image, the graphic operation panel 5 has a storage capacity of, for example, about several megabytes, and It has a sufficient calculation speed.
Therefore, the graphic operation panel 5 can perform the protocol conversion with a sufficient margin. Since the PLC 3 is not interposed between the graphic operation panel 5 and the control host computer 7, the PLC 3 can concentrate on the control of the target system 2. Therefore, the storage capacity and the processing capacity can be reduced as compared with the case where most of the communication is processed as in the conventional control system 501 shown in FIG. As an example of the processing with a large communication amount, there is a processing of downloading screen data from the control host computer 7 to the graphic operation panel 5 when converting a product manufactured by the target system 2 or the like.
However, in the control system 1 according to the present embodiment, since the screen data does not pass through the PLC 3, even when downloading the screen data, the PLC 3 can continue to operate normally with a small load.

Further, regardless of the type of the PLC 3, communication is performed between the graphic operation panels 5 and the control host computer 7 using a common protocol. Therefore, a plurality of types of PLCs 3 can be mixed in the same control system 1, and the range of model selection can be widened. Further, as in the conventional control system 501 shown in FIG. 9, in order to mix PLCs 503a having different communication protocols, the control system 501 is divided into sub-networks having different communication protocols, and the converter 510 is provided between the sub-networks. Unlike the case of distributing, the control system 1
Has a common communication protocol. Therefore, for example, devices connected to the common network 6, such as hubs, bridges, and routers, can be freely diverted, and the degree of freedom regarding the arrangement of these devices and the PLC 3 can be improved. In addition, since the converter 510 is unnecessary, the manufacturing cost of the entire control system 1 can be reduced.

The graphic operation panel 5 according to the present embodiment has, in addition to the above-described configuration, an authentication data storage unit 57 for storing authentication data (authentication data) as shown in FIG. A participant station storage unit (participant device information storage means) 58 for storing information (participating station information) indicating a legitimate device participating in the network 6 is provided. With reference to the storage unit 57 and the participating station storage unit 58, only authorized access is permitted. The data processing unit 54 corresponds to an access rejecting unit described in the claims. The data processing unit 54 and the authentication data storage unit 57 correspond to an authentication unit.

More specifically, when the graphic operation panel 5 receives a remote connection from the network device 8 connected to the common network 6, the authentication data storage unit 57 stores the authentication data in the authentication data storage unit 57. Data for determining whether the device is an authorized device is stored. The authentication data is stored in the data processing unit 54 before the remote connection of the network device 8.
For example, it is stored by being downloaded from the control host computer 7 or the like in accordance with the authentication method.

In the following, for convenience of explanation, as an example of an authentication method, a method is adopted in which when a password (remote password) sent at the time of remote connection matches a remote password stored in advance, it is determined that the network device 8 is authorized. The case will be described. In this case, the authentication data is the remote password itself, for example,
As shown in FIG. 5, in the control host computer 7, a remote password is input in advance and distributed to each graphic operation panel 5. Although FIG. 5 illustrates a case in which one remote password is set in the entire network and the same remote password is stored in the authentication data storage unit 57 of each graphic operation panel 5, each graphic operation panel 5 A password may be set for each access right or for each access right such as read permission (write permission).

On the other hand, the participant station storage unit 58 stores information indicating a legitimate network device 8 currently participating in the network as participant station information. For example, as shown in FIG. In the control host computer 7 or the like, the information is displayed in a list form, or as described later,
When the graphic operation panel 5 is accessed, it can be determined whether or not the access source is included in the participating station information. Note that the storage method of the participating station information is, for example, to store an ID (for example, an IP address or a serial number) identifying the registered network device 8 in a predetermined address area in order, or to list the ID in a list. For example, it is stored in such a manner that it can be determined whether or not the network device 8 is registered in the participating station information.

In the above configuration, the operation of each unit when the network device 8 accesses the graphic operation panel 5 will be described below with reference to FIGS. 7 and 8. That is, as shown in step 1 of FIG. 7 (hereinafter abbreviated as S1), when the network device 8 remotely connects to the graphic operation panel 5 by notifying a login command or a remote connection request, for example. In step S2, the graphic operation panel 5 determines whether or not the remote connection source is already registered in the participating station information with reference to the participating station storage unit 58. If the network device 8 has already been registered, the graphic operation panel 5 determines that the network device 8 is a legitimate device such as a device that has already been successfully authenticated, and permits remote connection in S6. The remote connection source,
The transmission source of an instruction such as a read / write instruction described later can be specified, for example, from the IP address of the transmission source stored in the header section 62 shown in FIG.

On the other hand, when the remote connection source is not registered in the participant station information of the participant station storage section 58, the graphic operation panel 5 returns to the authentication data storage section 5 in S3.
With reference to FIG. 7, for example, it is determined whether the remote password received from the network device 8 matches the remote password stored in the authentication data storage unit 57, and the network device 8 is authenticated. The network device 8 may spontaneously send the remote password, for example, by simultaneously sending a remote connection command and a remote password.
A remote password may be sent in response to an inquiry from the graphic operation panel 5.

At S3, the authentication data storage unit 57
When the authentication of the network device 8 succeeds, for example, when the remote password stored in the network device 8 matches the remote password received from the network device 8, the data processing unit 54 of the graphic operation panel 5 makes the network device 8 Is determined, the network device 8 is registered in the participating station information of the participating station storage unit 58 in S4, and the remote connection is permitted in S5.

Conversely, if the authentication of the network device 8 fails, such as when the two remote passwords do not match in S3, the graphic operation panel 5 rejects the remote connection in S7. In this case, since the processing of S4 is not performed, the network device 8 is not registered in the participating station information.

On the other hand, the graphic operation panel 5 is
As shown in S11, when an access command such as a read command or a write command is received from the network device 8 connected to the common network 6, in S12, as in the above S2, referring to the participating station storage unit 58, Then, it is determined whether or not the source of the access command is registered in the participating station information. If registered, the data processing unit 54 of the graphic operation panel 5 determines that the network device 8 is a legitimate device, and in S13, for example,
A process according to the received command, such as the above-described read process and write process, is performed.

On the contrary, when the access command is not registered in the participating station information, the data processing unit 54 determines that the source of the access command is not a legitimate device. In this case, the access from the network device 8 is rejected in S14 after S12.

In the above configuration, even if an unauthorized user attempts unauthorized access by connecting the network device 8 to the common network 6, the network device 8 is registered in the participating station information of the graphic operation panel 5. Therefore, the graphic operation panel 5 rejects the access. Further, for example, even if an attempt is made to register the own device in the participation station information by remote connection, the unauthorized user cannot succeed in the authentication in S3 of FIG. 7 and cannot register the network device 8 in the participation station information. .

Thus, for example, the network device 8
Are directly connected to the common network 6 or indirectly via a network device such as a router, for example, each graphic operation panel 5 can reject unauthorized access from the network device 8. Therefore, for example, the control system 1 such as information on the graphic operation panel 5, the PLC 3, or the target system 2.
Browsing, falsification or destruction of the information can be prevented. As a result, although a large-scale system can be constructed as compared with the conventional control system 501 shown in FIG. 9, the control system 1 that is strong against unauthorized access and safe can be realized.

On the other hand, since the authorized user knows the correct password, the authentication in S3 of FIG. 7 can be successful. Therefore, the own device can be registered in the participating station information, and the graphic operation panel 5 can be accessed without any trouble. Here, in the control system 1, since each graphic operation panel 5 and control host computer 7 are connected by the common network 6, the network device 8 can be directly connected to the common network 6, It can be connected indirectly via a network device such as. As a result, it is possible to access from a place distant from the target system 2 without any problem.

In this embodiment, a remote password is stored as authentication data, and when a remote password sent from the network device 8 at the time of remote connection matches a remote password stored in the authentication data storage unit 57 in advance, a formal password is stored. Although the case where the network device 8 is determined as described above has been described as an example, the present invention is not limited to this.
For example, when the data processing unit 54 of the graphic operation panel 5 authenticates the network device 8 using the one-time password, the authentication data storage unit 57 includes the network device 8 that generates the one-time password and the graphic operation panel. 5 may be stored. In any case, the same effect can be obtained if the authentication data storage unit 57 stores, as the authentication data, data that can authenticate whether the network device 8 is a legitimate device.

[0063]

As described above, the control display device according to the first aspect of the present invention includes a relay unit that relays communication using the dedicated protocol and communication using the common protocol, and a separate dedicated protocol interface. When the common protocol interface receives a remote connection, an authentication unit for authenticating the connection source device and registering the successfully authenticated device in the participating device information, and a participating device when receiving access from the network of the common protocol. An access rejecting unit that determines whether or not the access source is registered in the participating device information with reference to the information storage unit, and rejects the access when the access source is not registered is provided.

In the above configuration, since the control display device has the relay means, the control device and the control display device have
Control devices having different communication protocols can be easily mixed in a control system including a host computer and the like as necessary. Therefore, it is possible to greatly reduce the time and effort required to add the control device to the control system. Further, since the control display device includes the authentication means, even if an unauthorized user's device is connected to the common network, information on the control device and / or the device to be controlled is not sent to the device, and the information is not sent to the device. The controller does not receive instructions from the device. As a result, there is an effect that a control system having a large scale and protected from unauthorized access can be constructed.

As described above, the recording medium according to the second aspect of the present invention controls the first interface to communicate with the control device using a dedicated protocol, and controls the second interface to provide a predetermined common medium. Means for communicating with a protocol, means for controlling a display means to display information on a control device or a device to be controlled, means for relaying communication with the dedicated protocol and communication with a common protocol, and a connection source of a remote connection. Means for authenticating the device, registering and storing the successfully authenticated device in the participating device information, and determining whether or not the access source is registered in the participating device information; As a means for rejecting, a program for operating the computer is recorded.

When a program is read from the recording medium having the above configuration and executed by the computer, the computer operates as the control display device according to the first aspect. As a result, as in the case of the first aspect, as a result, there is an effect that a control system having a large scale and protected from unauthorized access can be constructed.

[Brief description of the drawings]

FIG. 1 illustrates one embodiment of the present invention, and is a block diagram illustrating a main configuration of a control system.

FIG. 2 is an explanatory diagram showing a communication protocol of a dedicated network and a data transfer format referred to when the graphic operation panel converts the communication protocol in the control system.

FIG. 3 is an explanatory diagram showing a communication protocol of a common network in the control system.

FIG. 4 is an explanatory diagram showing a command conversion table referred to when the graphic operation panel converts a communication protocol.

FIG. 5 is an explanatory diagram showing an example of a password setting screen in the control system.

FIG. 6 is an explanatory diagram showing an example of a display screen of a network participating station list in the control system.

FIG. 7 is a flowchart showing an operation of the control system and showing an authentication operation at the time of remote connection.

FIG. 8 is a flowchart showing the operation of the control system and showing the operation at the time of remote access.

FIG. 9 shows a conventional example, and is a block diagram showing a main configuration of a control system.

FIG. 10 is a block diagram showing a configuration of a prior application filed by the present applicant and showing a main configuration of a control system.

[Explanation of symbols]

2 Target System (Controlled Device) 3 Programmable Logic Controller (Control Device) 5 Graphic Operation Panel (Control Display Device) 51 Dedicated Network / IF Unit (Dedicated and First Protocol Interface) 52 Display Unit (Display Means) 54 Data processing unit (relay means, authentication means, access rejection means) 55 Common network / IF unit (common and second protocol interface) 56 Protocol conversion storage unit (relay means) 57 Authentication data storage unit (authentication means) 58 Participating stations Storage unit (participating device information storage means)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K034 AA05 AA20 FF11 FF18 GG02 GG06 HH17 HH26 KK04 LL01 LL02 5K048 BA23 DC04 EA14 FB08 FB10 FC01

Claims (2)

[Claims] A dedicated protocol interface for communicating with a control device connected to the control device by a dedicated protocol specific to the control device for controlling the control target device; and a display means for displaying information on the control device or the control target device. A control protocol display device having a common protocol interface provided separately from the dedicated protocol interface and communicating with a predetermined common protocol; and a relay for relaying communication with the dedicated protocol and communication with the common protocol. Means, participant device information storage means for storing participant device information in which devices participating in the network of the common protocol are registered, and, when remote-connected via the network of the common protocol, a connection source device. Authenticate and register the successfully authenticated device in the participating device information. The access means is registered in the participant information with reference to the participant information storage means when the access is received, and if the access source is not registered, the access is rejected. A control display device comprising an access rejecting means. 2. A recording medium on which a program for operating a computer having a first and second interface and a display unit different from each other as a control display device is recorded, wherein the first interface is controlled by: A dedicated protocol specific to the control device that controls the control target device.
Means for communicating with a control device connected to the interface; means for controlling the second interface to communicate with a predetermined common protocol; information for the control device or the device to be controlled by controlling the display means. Means for displaying, a means for relaying communication with the dedicated protocol and communication with the common protocol, and, when remotely connected via a network with the common protocol, a device that has authenticated the connection source device and succeeded in the authentication. Means for registering and storing in the participant information, and means for judging whether or not the access source has been registered in the participant information when access has been received, and for rejecting access when not registered. And a recording medium on which a program for operating the computer is recorded.