JP2007004671A - Access management device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an access management device in which competition of writing to field equipment is prevented by managing accesses from a plurality of users to the same field equipment. <P>SOLUTION: The access management device manages accesses from a plurality of users to field equipment, particularly, manages accesses from a plurality of users to field equipment between tools or between multi-clients of the same tool. This device comprises a user recognition means recognizing an exclusive access-allowed user in a main tool performing access from the plurality of clients to the field equipment via a server, a lock state management means limiting access from other than the user, and a check-out management means limiting access from the main tool in access to the field equipment from a sub-tool which performs access by directly connecting with the field equipment. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an access management apparatus that manages access from a plurality of users to a field device, and more particularly, to an access management apparatus that manages access from a plurality of users to a field device between tools or between multiple clients of the same tool. Is.

FIG. 3 is a diagram showing an example of conventional access from a plurality of users to a field device.
Access to the field device 1 may be performed by the server / client type main tool 10 or by the sub tool 20 directly connected to the field device 1.
In the main tool 10, a plurality of clients 10a1 and 10a2 access the field device 1 via the server 10b.
The sub tool 20 is a terminal device or the like in the field, and is directly connected to the field device 1 for access.

  For example, Patent Document 1 discloses an apparatus that can efficiently communicate between a preceding exclusive user and another user and eliminates the possibility of erroneous data reference.

JP-A-6-161925

The conventional example of FIG. 3 has the following problems.
When access requests from multiple users are processed at the same time for the same field device, there is no problem if there is only a read request, but when there is a write request, a series of writes, especially batch processing, makes sense. If so, the write request may result in an error if processed at the same time.
In addition, no error occurs, and the user who performed the writing thinks that a series of writing processing has been completed normally, but it is not actually written normally, which may hinder control of the field device. there were.

  The present invention has been made to solve the above-described problems, and realizes an access management apparatus that manages access from a plurality of users to the same field device and prevents contention in writing to the field device. Objective.

In order to achieve such a subject, the present invention is configured as follows.
(1) In an access management device that manages access to field devices,
A user recognition means for recognizing a user who is permitted exclusive access in a main tool that accesses a field device from a plurality of clients via a server;
Lock state management means for restricting access by users other than the user;
Check-out management means for restricting access from the main tool when accessing the field device from the secondary tool that is directly connected to the field device, and
An access management apparatus comprising:

(2) The lock state management means manages a lock state in which only the client that has performed the lock operation is allowed to write to the field device, and an unlock state in which no write operation is performed on the field device from any client. (1) The access management apparatus according to (1).

(3) The check-out state management means manages a check-out state in which writing from the main tool to the field device is prohibited and a check-in state in which writing from the main tool to the field device is permitted. The access management device according to (1) or (2).

(4) The access management apparatus according to (3), further comprising a data update unit that uploads a parameter from a field device when the checkout state changes to the checkin state.

(5) The client not performing the lock operation displays that the field device is in the locked state based on the lock state management unit and the user recognition unit, and displays the name of the client and the user who performed the lock operation. The access management apparatus according to any one of (2) to (4), wherein:

(6) The user recognition means recognizes access from an administrator user, and permits the administrator user to forcibly release the lock state of the lock state management means (2 The access management apparatus according to any one of (5) to (5).

As is apparent from the above description, the present invention has the following effects.
Manage not only access between clients in a server / client type main tool in which multiple clients are connected to the field device via the server, but also access between sub tools directly connected to the field device and the main tool. It is possible to prevent problems caused by contention in writing to the field device.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of the present invention. The same parts as those in the previous figure are given the same reference numerals.
The main tool 30 is connected to the field device 1 by a control system bus. The main tool 30 is a server / client type, and performs setting and adjustment of the field device 1.
The clients 30a1 and 30a2 and the server 30b are connected via a host network, and the clients 30a1 and 30a2 access the field device 1 via the server 30b.
The sub tool 20 is directly connected to the field device 1. The sub tool 20 is a terminal device or the like in the field, and performs setting and adjustment of the field device 1.

The lock state management unit 31a has a lock state in which only one client and one user acquire the write right (exclusive access right) to the field device 1, and the exclusive access right is still acquired by any client or user. Manage the unlocked state that is not done.
In the unlocked state without performing the locking operation, writing to the field device 1 cannot be performed. In the locked state, only the client and user who performed the locking operation can write to the field device 1, but other clients and users can refer to the parameters of the field device 1, but write I can't do it.

The checkout state management unit 31b prohibits writing from the main tool 30 to the field device 1 and checks out from the sub tool 20 to allow writing from the field device 1 and writing from the main tool 30 to the field device 1. Manage check-in states that allow
In the check-out state, the client and user of the main tool 30 can refer to the parameters of the field device 1 but cannot write them.
Based on the information of the check-out state management means 31b, it is possible to recognize that writing cannot be performed from the main tool 30 by displaying the check-out state in each client.

The user recognizing unit 31c recognizes the client accessing the server 30b, the client that performed the user recognition and lock operation, and the user.
When the field device 1 is already locked by one client and one user, the field device 1 is locked and the lock operation is performed based on the information of the lock state management means 31a and the user recognition means 31c. It is possible to recognize who is accessing by displaying the name of the performed client and user on each client.
The indication of the locked state includes, for example, a character “locking” or a key mark indicating that the lock is being performed.
Further, when the user recognition unit 31c recognizes the administrator user, it is possible to forcibly release the lock state of the lock state management unit 31a, thereby preventing problems caused by the unlock operation not being performed. it can.

  The data updating unit 31d uploads parameters from the field device 1 when the writing to the field device 1 from the sub tool 20 is completed and the checkout state management unit 31b changes from the checkout state to the checkin state. Thereby, data consistency with the field device 1 can be ensured in the main tool 30.

FIG. 2 is a flowchart showing the operation procedure of the present invention.
In FIG. 2, the writing operation to the field device 1 by the main tool 30 of FIG. 1 will be described.
When writing to the field device 1, it is selected whether to write with the main tool 30 or the sub tool 20 in FIG. 1 (S10). When the secondary tool 20 is not used, a check-in operation is performed (S20), and when the secondary tool 20 is used, a check-out operation is performed (S30).

  The user recognizing means 31c recognizes the client and the user who are going to write to the field device 1 (S40). Whether or not the check-out state management means 31b is in the check-out state is confirmed (S50). If the check-out state is in the check-out state, writing to the field device 1 from the main tool 30 is prohibited and the process ends. In the check-in state, it is confirmed whether or not the lock state management means 31a is in the lock state (S60). If another client or user has already performed a lock operation, writing to the field device 1 is prohibited and the process finish.

  When the lock state management means 31a is not in the locked state, the client or user who performs writing can perform writing to the field device 1 by performing a locking operation (S70) (S80). After writing, the lock state management means 31a is unlocked (S90), and the process is terminated.

  By these lock state management means 31a and checkout state management means 31b, not only access between the clients 30a1 and 30a2 in the main tool 30, but also between the sub tool 20 and the main tool 30 directly connected to the field device 1 are different. Access can also be managed. As a result, a write request error due to a conflict in writing to the field device 1 can be prevented, and data consistency is ensured even in a writing process in which a series of writing processes are meaningful, such as batch processing. be able to.

It is a block diagram which shows one Example of this invention. It is the flowchart which showed the operation | movement procedure of this invention. It is the figure which showed the example of the conventional access from the multiple users to a field apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Field apparatus 20 Sub tool 30 Main tool 30a1, 30a2 Client 30b Server 31 Access management apparatus 31a Lock state management means 31b Checkout state management means 31c User recognition means 31d Data update means

Claims (6)

In an access management device that manages access to field devices,
A user recognition means for recognizing a user who is permitted exclusive access in a main tool that accesses a field device from a plurality of clients via a server;
Lock state management means for restricting access by users other than the user;
Checkout management means for restricting access from the main tool when accessing the field device from a secondary tool that is directly connected to the field device, and
An access management apparatus comprising:   The lock state management means manages a lock state in which only the client that has performed the lock operation is allowed to write to the field device, and an unlock state in which no write operation to the field device is performed from any client. The access management apparatus according to claim 1, wherein:   The check-out state management unit manages a check-out state in which writing from the main tool to a field device is prohibited and a check-in state in which writing from the main tool to the field device is permitted. Item 3. The access management device according to Item 1 or 2.   4. The access management apparatus according to claim 3, further comprising a data update unit that uploads a parameter from a field device when the check-out state changes to the check-in state.   The client not performing the lock operation displays that the field device is in the locked state based on the lock state management means and the user recognition means, and displays the name of the client and user who performed the lock operation. The access management apparatus according to claim 2, wherein the access management apparatus is characterized in that: 6. The user recognizing unit recognizes an access from an administrator user, and permits the administrator user to forcibly release the lock state of the lock state managing unit. The access management device according to any one of the above.