JP2004266689A - Method for controlling apparatus connected to internal network, relay control apparatus, and relay control program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new technology capable of controlling a plurality of apparatuses connected to an internal network in response to an instruction from a remote control apparatus connected to an external network via a firewall. <P>SOLUTION: The internal network periodically connects with the external network via the firewall to receive a control instruction applied to control object apparatuses, transfers the control instruction to the control object apparatus designated by transfer destination information recorded in a header of the received control instruction, receives a result of the execution, and returns the result to the external network as a reply with respect to the received control instruction so as to control the control object apparatus connected to the internal network. Thus, even when the plurality of control object apparatuses exist, the internal network can control the control object apparatuses in response to the instruction from the external network. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control method for controlling a plurality of devices connected to an internal network in response to an instruction from a remote control device for connection to an external network connected via a firewall, and a relay control implementing the control method. The present invention relates to a device and a relay control program used for realizing the relay control device.
[0002]
[Prior art]
A manufacturer that manufactures process control equipment or the like has a request to collect maintenance information of its own products that are operating at a company to which the product is delivered after delivering the product such as the process control equipment.
[0003]
Normally, such a process control device or the like is connected to an in-house network of a delivery destination company and operates.
[0004]
On the other hand, in order to ensure the security of in-house information, each company has provided a firewall between the in-house network and the Internet, and has taken measures to prohibit external access to the in-house network.
[0005]
From now on, if a manufacturer that manufactures process control equipment, etc. wants to collect maintenance information on its products running at the company to which it is delivered after delivering products such as process control equipment, However, there is a problem that this cannot be realized by the firewall provided.
[0006]
Against this background, the applicant of the present invention converts a communication protocol in Patent Document 1 shown below to connect a device connected to an internal network to an external network via a firewall. The invention has been disclosed that enables connection to a device.
[0007]
By using this invention, a manufacturer that manufactures process control equipment, etc., collects maintenance information on its own products running at the company to which it is delivered after delivering products such as process control equipment. It can be realized.
[0008]
[Patent Document 1]
JP-A-2000-172597 (Japanese Patent Application No. 10-348435)
[0009]
[Problems to be solved by the invention]
According to the invention disclosed by the present applicant, since a connection is established from an internal network side to an external network via a firewall, manufacturers that manufacture process control devices and the like require After delivering products such as equipment, it will be possible to collect maintenance information on their own products running at the company to which they are delivered.
[0010]
The present invention uses the invention disclosed by the present applicant to provide a specific mechanism for collecting information from a plurality of devices connected to an internal network from those devices. By constructing, for example, a more practical technology that enables a manufacturer that manufactures process control equipment, etc. to collect maintenance information on its own products running at the company to which it is delivered after delivering the product The purpose of this is to construct.
[0011]
By constructing this technology, it becomes possible to construct a more practical system when controlling various devices connected to the internal network protected by the firewall.
[0012]
As described above, the present invention provides a new technology that can control a plurality of devices connected to an internal network in response to an instruction from a remote control device for connecting to an external network connected via a firewall. The purpose is to provide.
[0013]
[Means for Solving the Problems]
In order to achieve this object, the relay control device of the present invention is connected to the internal network, and is connected to the internal network in response to an instruction from the remote control device of the external network connection connected via the firewall. In order to perform a process of controlling a plurality of control target devices, (1) a connection is periodically established with a remote control device, and control commands for the control target devices stored in the remote control device are transmitted. Means for requesting transmission; and (2) receiving a control command returned in response to the request, transferring the control command to a device to be controlled specified by the control command, and executing the command. Means for receiving the result; and means for returning the execution result to the remote control device as a response to the control command.
[0014]
Each of the above processing means can be realized by a computer program, and this computer program can be provided by being recorded on a recording medium such as a semiconductor memory, or can be provided via a network.
[0015]
In the relay control device of the present invention configured as described above, the relay control device is periodically connected to the remote control device, and requests transmission of a control command to the control target device stored in the remote control device. .
[0016]
Subsequently, in response to this request, a control command is returned from the remote control device. Therefore, the control command is received and the transfer destination information recorded in the header of the control command is received. By extracting, the control target device to which the control command is transferred is specified, and the control command is transferred to the specified control target device.
[0017]
Subsequently, an execution result is returned from the control target device in response to this transfer. The execution result is received, and the execution result is returned to the remote control device as a response to the control command.
[0018]
As described above, according to the present invention, when the control target device is connected to the internal network protected by the firewall, the connection from the internal network side to the external network via the firewall is periodically performed. In order to receive the control command for those controlled devices, the control command is transferred to the controlled device specified by the transfer destination information recorded in the header of the received control command, and the execution result is obtained. The control target device connected to the internal network is configured by controlling the control target device connected to the internal network by receiving it and returning it to the external network as a response to the received control command. Responds to instructions from the external network side even if there are multiple It becomes possible to control the control target device.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail according to embodiments.
[0020]
FIG. 1 shows an example of a system to which the present invention is applied.
[0021]
As shown in this figure, a system to which the present invention is applied performs a process of controlling a control target device 2-i (i = 1 to n) connected to an internal network 3 protected by a firewall 4. And a control command issued to one or a plurality of client terminals 6 connected to the external network 5 for the control target device 2-i, and the relay control device 1 according to the present invention. 1 and a remote control device 7 for performing a process of remotely controlling the control target devices 2-i (i = 1 to n) connected to the internal network 3 by exchanging with the internal network 3.
[0022]
When configured in this manner, the remote control device 7 includes an instruction accumulation buffer 70 that accumulates a control instruction for the control target device 2-i issued by the client terminal 6.
[0023]
In addition, each control target device 2-i displays a homepage serving as a control start screen in addition to the control function, and from that point, what control processing (including information collection) is performed on the control function. A server function is provided for performing processing for setting whether to execute.
[0024]
First, the processing executed by the remote control device 7 according to the processing flows of FIGS. 2 and 3 will be described.
[0025]
Here, the processing flow of FIG. 2 is processing that the remote control device 7 executes when a control request is issued from the client terminal 6 to the control target device 2-i. The flow is a process to be executed by the remote control device 7 when a request to transmit a control command is issued from the relay control device 1.
[0026]
When a control request is issued from the client terminal 6 to the control target device 2-i connected to the internal network 3, the remote control device 7 first performs the steps shown in the processing flow of FIG. At 10, a device selection screen as shown in FIG. 4 is displayed on the client terminal 6 that has issued the control request.
[0027]
Here, in addition to having a user ID input area and a password input area, the device selection screen has a display area for selecting a control target device 2-i to be controlled according to a click operation.
[0028]
Upon receiving the display of the device selection screen, the user operating the client terminal 6 inputs a user ID, a password, and a device name of the control target device 2-i to be controlled.
[0029]
Then, in step S11, the user ID, password, and control target device name input by the user are input, and in step S12, user authentication is executed using the input user ID and password.
[0030]
After the user is authenticated, subsequently, in step 13, a home page transfer instruction having header information with the transfer destination being the control target device 2-i indicated by the input control target device name (normally, the home pages are sequentially displayed. (Which is composed of a plurality of instructions).
[0031]
That is, in order to issue a control command to the control target device 2-i indicated by the input control target device name, first, a homepage (control start screen) for acquiring a home page (control start screen) from the control target device 2-i. The homepage transfer command is registered in the command storage buffer 70.
[0032]
Then, at this time, information indicating that the control target device 2-i indicated by the input control target device name is the transfer destination is added to the header of the homepage transfer instruction.
[0033]
Subsequently, in step 14, the process waits for the issuance of a processing request from the client terminal 6 that has issued the control request, and when the processing request is issued, the process proceeds to step 15 to determine whether the request is a processing end request. Is determined to be a control command issued starting from.
[0034]
When it is determined that a control command has been issued from the client terminal 6 that has issued the control request according to this determination process, the process proceeds to step 16, and the header of the issued control command indicates the input control target device name. After adding information indicating that the control target device 2-i is the transfer destination, the issued control command is registered in the command storage buffer 70, and the process returns to step 14 to wait for the next control command to be issued. .
[0035]
On the other hand, in step 15, when it is determined that the processing end request has been issued from the client terminal 6 that has issued the control request, it is determined that the control operation to the control target device 2-i has been completed, and the processing is terminated. I do.
[0036]
In this way, when the control command is issued from the client terminal 6 to the control target device 2-i, the remote control device 7 selects the header of the issued control command on the device selection screen. After adding information indicating that the control target device 2-i indicated by the control target device name is the transfer destination, processing is performed so that the issued control commands are stored in the command storage buffer 70.
[0037]
Next, a process executed when the remote control device 7 receives a request to transmit a control command from the relay control device 1 according to the process flow of FIG. 3 will be described.
[0038]
When a request to transmit a control command is issued from the relay control device 1, the remote control device 7 first stores the control command in the command storage buffer 70 in step 20, as shown in the processing flow of FIG. It is determined whether or not it is.
[0039]
When it is determined that the control command is not stored in the command storage buffer 70 according to this determination process, the process proceeds to step 21 to determine whether or not a predetermined time has elapsed. When the determination is made, the process returns to step 20, and when it is determined that the predetermined time has elapsed, the process proceeds to step 22, where no control command is returned to the relay control device 1, and the process ends.
[0040]
On the other hand, when it is determined in step 20 that the control command is stored in the command storage buffer 70, the process proceeds to step 23, where one control command is extracted from the command storage buffer 70, and in step 24, the relay control device 1 is returned to the control command.
[0041]
At this time, the destination of the control command returned is the relay control device 1, but the header of the control command includes the control target device 2-i indicated by the control target device name selected on the device selection screen described above. Information indicating that it is a transfer destination is added.
[0042]
As will be described later, the relay control device 1 receives the reply of the control command, transfers the returned control command to the control target device 2-i designated as the transfer destination, receives the execution result, It is returned as a response to the control command.
[0043]
Subsequently, in step 25, the process waits for the execution result from the relay control device 1 to be returned to the control target device 2-i. When the execution result is returned, the process proceeds to step 26. The execution result is returned to the client terminal 6 that issued the control request.
[0044]
Subsequently, at step 27, it is determined whether or not the instruction storage buffer 70 has become empty. When it is determined that the instruction storage buffer 70 has not become empty, processing for the next control instruction is performed. Returning to step 23, when it is determined that the command storage buffer 70 is empty, the process proceeds to step 28, where the relay control device 1 is notified that there is no control command, and the process ends.
[0045]
In this way, when the transmission request of the control command is issued from the relay control device 1, the remote control device 7 fetches one control command from the command storage buffer 70 and returns it, and executes the execution as a reply thereto. It receives the result and processes it to return it to the client terminal 6 that issued the control request.
[0046]
Next, the processing executed by the relay control device 1 according to the present invention will be described in detail with reference to the processing flows of FIGS.
[0047]
When the relay control device 1 having the present invention is started, as shown in the processing flows of FIGS. 5 and 6, first, in step 30, it is determined whether or not a specified request period has been reached. When it is determined that the specified request cycle has been reached, the process proceeds to step 31 to connect the remote control device 7 through the firewall 4 and request the remote control device 7 to transmit a control command. .
[0048]
In response to the transmission request of the control command, the remote control device 7, when the control command is stored in the command storage buffer 70 as described in the processing flow of FIG. One command is fetched and returned, and if no control command is stored in the command storage buffer 70, no command is returned.
[0049]
From now on, in step 32, when waiting for a reply from the remote control device 7 and determining that nothing has been returned, the process proceeds to step 33, in which it is determined whether or not a predetermined time has elapsed. When it is determined that the predetermined time has not elapsed, the process returns to step 32. When it is determined that the predetermined time has elapsed, the process proceeds to step 34, where the path to the remote control device 7 is disconnected. Then, the process returns to step 30 to wait for the next request cycle.
[0050]
That is, even if the predetermined time has elapsed, the fact that nothing is returned from the remote control device 7 means that a failure may have occurred in the network or the like. The processing is performed so as to cut off the path between the first and second paths.
[0051]
On the other hand, when it is determined in step 32 that there is a reply from the remote control device 7, the process proceeds to step 35, where it is determined whether a control command has been returned from the remote control device 7 and the control command is returned. When it is determined that the communication has not been performed, that is, when it is determined that no control command has been returned, the process proceeds to step 36, where the path to the remote control device 7 is disconnected, and The process returns to step 30 in order to wait for the requested cycle.
[0052]
On the other hand, when it is determined in step 35 that the control command has been returned from the remote control device 7, the process proceeds to step 37, and the transfer destination information added to the header of the returned control command is extracted.
[0053]
That is, when the remote control device 7 returns the control command issued from the client terminal 6, the remote control device 7 includes, in the header of the control command, the control target device 2-indicated by the control target device name selected on the device selection screen. Since the information indicating that i is the transfer destination is added, the relay control device 1 extracts the transfer destination of the returned control command according to the additional information.
[0054]
Subsequently, in step 38, the control command returned from the remote control device 7 is transferred to the control target device 2-i indicated by the extracted transfer destination information.
[0055]
That is, the control command returned from the remote control device 7 is not to be executed by the relay control device 1 equipped with the present invention, but the control target device 2 indicated by the control target device name selected on the device selection screen. Since -i is to be executed, the control command returned from the remote control device 7 is transferred to the control target device 2-i.
[0056]
Upon receiving the control command, the control target device 2-i receives the control command from the relay control device 1, executes the control command, and returns the execution result to the relay control device 1.
[0057]
Subsequently, in step 39, the process waits for the execution result to be returned from the control target device 2-i. When the execution result is returned, the process proceeds to step 40, where the remote control device 7 The returned execution result is returned as a response to the control command.
[0058]
That is, the returned execution result is returned as a response to the control command sent from the remote control device 7.
[0059]
In response to the return of the execution result, the remote control device 7 determines whether or not the instruction storage buffer 70 is empty, as described in the processing flow of FIG. If not, the next control command is returned, and if the command storage buffer 70 becomes empty, no control command is returned.
[0060]
Subsequently, in step 41, after waiting for a reply from the remote control device 7, when the next control command is returned, the process returns to step 37 to process the control command, and there is no control command. Is returned, the process proceeds to step 42, disconnects the path to the remote control device 7, and then returns to step 30 to wait for the next request cycle.
[0061]
In this way, the relay control device 1 equipped with the present invention connects to the remote control device 7 through the firewall 4 when the specified request period is reached, as shown in FIG. Is requested to send a control command ((1) in the figure). When the control command is returned in response ((2) in the figure), it is added to the header of the control command. By transferring the control command to the control target device 2-i indicated by the transfer destination information ((3) in the figure), an execution result for the control command is obtained ((4) in the figure). The execution result is processed so as to be returned to the remote control device 7 as a response to the sent control command ([5] in the figure).
[0062]
When the relay control device 1 having the present invention configured as described above is used, when a plurality of control target devices 2-i are connected to the internal network 3 as shown in FIG. Since the device 2-i does not need to have a function for connecting to the remote control device 7 through the firewall 4, each control target device connected to the internal network 3 from the external network 5 according to a simple configuration. 2-i can be controlled.
[0063]
【The invention's effect】
As described above, according to the present invention, when the control target device is connected to the internal network protected by the firewall, the internal network side periodically connects to the external network via the firewall. As a result, the control command for the control target device is received, and the control command is transferred to the control target device specified by the transfer destination information recorded in the header of the received control command, and the control command is executed. By receiving the result and returning it to the external network as a response to the received control command, the control target device connected to the internal network is controlled, so that the control target connected to the internal network is controlled. Even if there are multiple devices, it will respond to instructions from the external network side. And it becomes possible to control the control target equipment.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a system to which the present invention is applied.
FIG. 2 is an example of a processing flow executed by a remote control device.
FIG. 3 is an example of a processing flow executed by a remote control device.
FIG. 4 is an explanatory diagram of a device selection screen.
FIG. 5 is an example of a processing flow executed by a relay control device having the present invention.
FIG. 6 is an example of a processing flow executed by a relay control device having the present invention.
FIG. 7 is an explanatory diagram of the present invention.
FIG. 8 is an explanatory diagram of the present invention.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 relay control device 2 controlled device 3 internal network 4 firewall 5 external network 6 client terminal 7 remote control device 70 command storage buffer

Claims (4)

A control method for controlling a plurality of devices connected to an internal network in response to an instruction from a remote control device for connecting to an external network connected via a firewall,
Periodically connecting to the remote control device, requesting transmission of a control command to the device stored in the remote control device,
Receiving the control command returned in response to the request, transferring the control command to the device specified by the control command, and receiving an execution result corresponding thereto;
Returning the execution result to the remote control device as a response to the control command,
A method of controlling a device connected to an internal network. A method for controlling a device connected to an internal network according to claim 1,
In the receiving step, if the control command is not returned within a prescribed time from the remote control device, disconnecting the connection with the remote control device,
A method of controlling a device connected to an internal network. A relay control device that is connected to the internal network and controls a plurality of devices connected to the internal network in response to an instruction from a remote control device for external network connection connected via a firewall,
Means for periodically connecting to the remote control device and requesting transmission of a control command to the device stored in the remote control device;
Means for receiving the control command returned in response to the request, transferring the control command to the device specified by the control command, and receiving an execution result corresponding thereto;
Means for returning the execution result to the remote control device as a response to the control command,
Characteristic relay control device. Used for realizing a relay control device that is connected to an internal network and controls a plurality of devices connected to the internal network in response to an instruction from a remote control device for connection to an external network connected via a firewall. A relay control program,
A process of periodically connecting to the remote control device and requesting transmission of a control command to the device stored in the remote control device;
Receiving the control command returned in response to the request, transferring the control command to the device specified by the control command, and receiving an execution result corresponding thereto;
A relay control program for causing a computer to execute a process of returning the execution result to the remote control device as a response to the control command.

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