JPH03283846A - Communication system - Google Patents

Abstract

PURPOSE:To easily change information in a short time in accordance with the system change by receiving an information gathering request from a slave station to transmit information to this slave station at the time of acquiring the operation right as a master station and storing information received from the master station in an external storage medium to update it at the time of operation as a slave station. CONSTITUTION:A station having the master station function in a ring shaped local area network(LAN) is provided with an external storage medium read/ writre device 16 to which not only the function to read out stored contents of an external storage medium 20 but also the function to written information in this medium is added. When the station acquires the operation right as the master station, it receives the information gathering request from slave stations to transmit station start and operation information to them; and when the station is operated as a slave station, it stores station start and operation information received from the master station in the external storage medium 20 to update it. Thus, contents of the external storage medium 20 in a remote station are easily changed and are rewritten in a short time.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Industrial Application Field) The present invention relates to a communication network system such as a LAN (Local Area Network), and particularly relates to operation management necessary for a station having a master station function in a network. The present invention relates to a communication system that allows information to be easily changed.

(Prior art) In a network such as a LAN (Local Area Network), multiple communication stations are sequentially connected using communication cables, etc., and connected in a ring (loop) shape or bus shape, and each station performs transmission and reception. When doing so, for example, data is transmitted to the other station by packet transmission or time division multiplex transmission, etc., and each station receives the transmitted data and imports it into itself if it is relevant to itself. conduct.

Among the plurality of stations, one station has the right to operate and manage the network, and the station that has the right to operate and manage the network becomes the master station. The other stations become slave stations, and under the operational management of the master station, each slave station can exchange information with other stations via communication channels.

By the way, conventionally in this type of loop-type LAN, station startup/operation information (software for station startup, station configuration information, operation management information such as port and transmission frame configuration information) is stored in an external storage medium. , the information can be written to by a workstation or the like in order to change it.

On the other hand, in order to avoid the risk of the LAN going down due to a failure of the master station, among the plurality of stations connected to the network, a plurality of stations are designed to have a functional configuration that can serve as the master station. That is, among the stations connected to the LAN, there are a plurality of stations each having the external storage medium.

Each station with a functional configuration that can become a master station loads the stage activation and operation information from the external storage medium into the station's main memory in order to obtain loop operation management rights (LAN operation management rights). If the station can start up first among the stations, it will gain operational management rights and become the master station. Since the master station generates a carrier and supplies this carrier to the communication path, other stations recognize this carrier and execute the following start-up operation as a slave station.

For example, each slave station, including the remaining stations with a functional configuration that can become a master station (hereinafter, stations with a functional configuration that did not become a master station will be referred to as standby master stations), For the station (master station),
First, a DLL request (a request to collect information from the master station) is made, and based on this, the master station
The slave station that has issued the LL request is recognized as a slave station and provided with the necessary information as a slave station (including information necessary for the standby master station to function as a master station). information) and permission to start up, the slave station receives this information, and then starts up as a slave station based on the received information.

Each slave station exchanges such information with the master station and starts up in turn. When all the slave stations that have issued DLL requests have started up, the LAN operation begins under the control of the master station.

When the master station becomes abnormal and LAN operation is disrupted, the standby master station that recognizes the abnormality and has a higher priority takes over the master station function and operates as the new master station. This allows you to operate the LAN. This is because the master station generates a carrier and supplies this carrier to the communication path, so if the standby master station is equipped with this carrier monitoring function, when the carrier stops, one of the standby master stations The station with the highest priority will immediately start operating as the master station, and the other stations will operate as slave stations under the management of this new master station.
In addition, in order to cope with the case where the LAN is restarted from the beginning with itself as the parent, it is possible to store the station startup and operation information in an external storage medium and store it automatically. This will load the main memory of the station so that it can be started up.

Therefore, when there is a change in the LAN system, etc., it is necessary to provide the master station and the standby master station with station startup/operation information that matches the new system. When changing such station startup/operation information, it is recommended that all of this information be stored on an external storage medium, so each station with master station functions, including standby master stations, It is necessary to change the contents of the external storage medium held by the computer to new contents.

However, since the station only has a read function to read external storage media, the external storage medium must first be removed from the station and written to the external storage medium using the external storage medium writing function of the workstation, etc. It required a lot of work, and changing information was troublesome. This is particularly true in the case of a network where each station is far apart, and if the remote station does not have a writing device to write to an external storage medium, it is necessary for a person to go to the site where the station is installed. This means that it is necessary to collect the external storage medium, change the information content to new content, and then return to the site and reinstall the external storage medium, which is extremely troublesome work.

(Problems to be Solved by the Invention) As described above, a network such as a LAN is configured by connecting a plurality of stations to a communication path, and information can be exchanged between each station. A station serving as a master station operates and manages the network, and other stations operate as slave stations under the management of the master station. In such a system, if the master station stops working properly or if it becomes necessary to remove the current master station and restart the system, it will no longer be able to function as a network, so the functions of the master station are generally It is normal for several stations to have one. In order to have a master station function, software to start up the own station and various information for network operation are required.
Operation management information such as station startup and operation information is stored in an external storage medium in a station equipped with a master station function.

Then, at the initial stage of LAN operation, the operation management information is read from this external storage medium, loaded into the main memory of its own station, and based on this, it becomes possible to start operation and operate as a master station.

Therefore, when there is a system change, etc., it is necessary to update the content to match the change. However, since a station with a master station function only has a read function to read the external storage medium, the external storage medium must be removed from the station, the contents of the external storage medium must be rewritten with new contents, and then the external storage medium must be inserted. Changing the information was extremely troublesome as it required some work to correct it.

Therefore, especially in the case of a network where each station is far apart and there is no writing device at the site, it is necessary to go to the station installation site, collect the external storage medium, and change the information content to new content. However, this means that it is necessary to go back to the site and reinstall the external storage medium, which is extremely troublesome work, and has the disadvantage that changes require a lot of effort and time.

Therefore, an object of the present invention is to be able to easily change the contents of an external storage medium at a remote station without going to the remote station, and to save time and effort even if the system is changed. To provide a communication system that allows content to be rewritten without any trouble.

[Configuration of the Invention (Means for Solving the Problem) In order to achieve the above object, the present invention is configured as follows. In other words, a plurality of stations are connected via communication lines to form a network, and at least two of the stations are provided with a master station function, and each station with the master station function is configured to activate the station and network. An external storage medium is provided in which information for operation is stored, and when the external storage medium is initially loaded and started up for the first time, it acquires the right to operate and manage the network as a master station.
Other stations make requests to the master station to collect information, and in response to this request, the master station sends information necessary as a slave station to the requesting station, and the requesting station that receives this sends the received information. When the operating master station becomes abnormal, another station with the master station function becomes the master station, acquires the right to operate and manage the network, and operates the system. In the communication system, each station having the master station function has a read/write control means for controlling reading/writing of stored information on the external storage medium, and a read/write control means for controlling the reading/writing of stored information on the external storage medium, and a read/write control means for controlling the reading/writing of stored information from the slave station. a first transmitting station start-up, network operation information and information necessary as a slave station to the requesting slave station;
and a second control means for controlling the read/write control means to cause at least the external storage medium to update and store information for starting the station and for network operation sent from the master station when operating as a slave station. and the means for.

(Function) In this system with such a configuration, there are multiple stations with a master station function, and the station with a master station function is provided with an external storage medium to store information for station startup and network operation. It's a reminder. Then, when the station reads this external storage medium at the initial stage and starts up before other stations, that station acquires the right to operate and manage the network and begins to operate and manage the network as a master station. The other stations make a request to the master station to collect information, and in response to this request, the master station sends the necessary information as a slave station to the requesting station, and the requesting station receives the received information. Based on this, the slave station transmits the information it owns for starting up the station, operating the network, etc., as well as information necessary as a slave station, to the requesting slave station.

When the slave station that has received this information is a station that has a master station function, the second means is that among the information received from the master station, the information for starting the station and operating the network is sent to the own station. The read/write control means of the own station is controlled in order to update and store information in the external storage medium of the local station.

For example, the present invention is configured such that a station with a master station function in a ring-type LAN has not only the function of reading out the stored contents of an external storage medium, but also the function of writing the contents, and acquires the right to operate as a master station. When the station receives an information collection request from a slave station, it transmits the station startup/operation information to the slave station, and when operating as a slave station, the station startup/operation information received from the master station is stored in the external storage medium. Since it is designed to be updated and memorized,
If you store station startup series information in an external storage medium in a station with a master station function and start up this station as a master station, other stations with master station functions will start their stations from the station that started up as a master station. - Can receive operational information and update and store it in its own external storage medium. Therefore, if there is a change in the system and you want to update the station startup/operation information stored in the external storage medium of each station, you can start a new station in the external storage medium for one of the stations that has the master station function. - By storing the operation information and restarting the system so that this station becomes the master station, new station startup and operation information can be updated to the external storage media of other stations with master station functions. It will be possible to memorize it.

Therefore, when changing the system, etc., the station startup/operation information on the external storage medium of one station is rewritten, and that station is started as the master station.
For remote stations with external storage media,
Just by performing a forced reset from the master station, the remote station will start up again from the beginning and update the DLL.
Since the request goes (as the station with management rights has already been determined), the station's main memory contents and external storage medium contents can be changed to new information, and therefore the slave station with master station function As the parent station,
It is now possible to start up the station at any time with new station start-up/operation information, without having to make system changes.
Moreover, it can be done in a short time.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram illustrating an embodiment of the present invention, and FIG. 2 is a system outline diagram of a ring-type LAN consisting of six stations as an example. System 7a and secondary system 7b 2
It is expressed as a station with a heavy system.

In FIG. 2, numbers 6 to 6 are stations, the fourth station 4 is the master station, and the first station 1 is the main station.
and the 6th station 6 is the standby master station, and the 2nd station 2
and the third station 3 are slave stations. These stations 1 to 6 are connected by primary and secondary optical fiber cables, so that the communication paths are duplicated.

The first station 1, the fourth station 4, and the sixth station basically have the same functional configuration, and each has an external storage medium that stores the information necessary to operate and manage this LAN system. It has the function of a master station. The fourth station 4 is the current master station that operates and manages the LAN system, and here it is assumed that the workstation 8 is connected only to the fourth station 4. The workstation 8 is capable of exchanging data with the first station 1 and giving various commands.

The LAN system is connected by duplicated communication paths 7a and 7b using optical fiber cables, and the station status of the system can be known from the workstation 8 and the like.

Standby master station 1, 5.6 is master station 4
When the system goes down due to a malfunction, or when there is a request for a friendship ceremony from a terminal, it is possible to take turns in operating and managing the Konoroop system.

Station 2.3 has no external storage medium;
Therefore, it is a slave station that does not have the function of operating and managing the system.

FIG. 1 shows a schematic configuration of stations 1, 4, 5, and 6 having master station functions.

In the figure, 11 is a CPU, 12 is a main memory, 1
3 is a basic unit, 14 is a conversion unit, 15 is an I10 unit, 16 is an external storage medium read/write device, 17 is a bus, and 20 is a large capacity external storage medium.

The external storage medium read/write device 16 is an external storage medium 20
The 110 section 15 is for exchanging control signals and information with an input/output operation terminal such as a workstation 8, which is a man-machine interface. The CPU II is a processor that controls the control of the own station, and the main memory 12 is used for storing control programs and data executed by the CPU II, and as a working area. In the main memory 12, when the own station starts up as a slave station, it sends a DLL request to the master station, and when it receives the station start-up/operation information sent from the master station, it stores this information in the own station. The external storage medium 20 is provided with a function of controlling the external storage medium read/write device 16 in order to update and store the information in the external storage medium 20 .

The basic unit 13 is in charge of basic functions as a station, and performs a carrier generation function, a carrier monitoring function, synthesis, separation and extraction of transmitted and received data, etc. necessary when functioning as a master station. These are connected by a bus 17, and data and control commands can be exchanged on the bus 17.

The converting unit 14 is a transmitting/receiving unit that performs photoelectric conversion of carriers sent from the basic unit 13 and data to be transmitted and received, and includes carriers in communication paths 7a and 7b formed by optical fiber cables.
In addition to the function of transmitting transmission data as an optical signal and converting the received optical signal into an electrical signal, it has an opening/closing function of opening and closing the communication paths 7a and 7b.

This opening/closing function may be performed by operating a manual switch provided in the converter 14, or may be performed by an opening/closing command from the workstation 8 as a remotely controllable switch. In addition, a large capacity external storage medium 20
is for storing station startup/operation information, etc., and the external storage medium read/write device 16 performs data read/write control for the external storage medium 20 under the control of the CPU II.

This apparatus having such a configuration can perform various operations when the workstation 8 issues a command to the master station 4 at the master station 4.

Now, suppose that due to a change in the LAN system, etc., it is necessary to provide station start-up and operation information suitable for the new system. In this case, the converter 14 opens the communication channels 7a and 7b by opening the manual switch of the converter 14 or by giving an open operation command from the workstation 8 to the remote control switch of the converter 14, resulting in carrier disconnection. . As a result, the stations 1 to 3 and 5.6 connected to the communication paths 7a and 7b no longer receive the carrier.

When the carrier is no longer received, the standby master station determines that there is an abnormality in the master station, and the standby master station with a higher priority takes over as the master station. That is, L
When the AN is initialized, a station with a master station function reads information from its own external storage medium and then starts up.

Then, the station that starts up first becomes the master station, and as a result, other stations make DLL requests.
Get all the necessary information from the master station.

Therefore, at this stage, the station that becomes the standby master station has received information from the master station that it is a standby master station, including the information necessary to function as a master station, and is therefore unable to function as a master station. Therefore, when a master station malfunctions, a station with a high priority among standby master stations immediately obtains operation rights and starts operating as a master station.

The LAN is then operated at stations other than the original master station 4. Since there are two communication paths and a ring-shaped connection configuration, the station adjacent to station 4 turns around as the end of the communication path, forming a new loop to exchange information.

In the station 4 disconnected from the LAN, the workstation 8 sends a rewrite command to the external storage medium 20 and new rewrite data, and the CPU II of the station 4 receives this via the I10 unit 15. Since it is sent to the external storage medium read/write device 1g together with the write command, the external storage medium read/write device 1B writes this new information to the external storage medium 20.

Next, when it is desired to start operating the LAN with this new system configuration, a reset is performed from the workstation 8. As a result, the CPU II of the station 4 initializes and then controls the external storage medium read/write device 16 in order to read out the station startup/operation information stored in the external storage medium 2°. New station startup/operation information stored in 20 is read out, and CPU II loads these into main memory 12. Next, in order to participate in the LAN loop, a closing operation is performed on the opening/closing mechanism of the conversion unit 14 in order to cause the carrier to flow.

As a result, station 4 joins the LAN as a standby master station with new information.

In order for station 4 to participate as a master station, the operator issues a command from workstation 8 to station 4 to start the master station operation. Then, the station 4 CP
The UII executes the station startup program loaded into the main memory 12 and gives a master replacement command to the current master station operating in the LAN, causing the current master station to operate as a slave station.

As a result, station 4 obtains the right to operate and manage itself with new information.

Next, the operator operates the workstation 8 and instructs the station 4 to issue a reset command to the standby master station (stations 1, 5, and 6). Then, the CPU II of station 4 issues a reset command to the standby master station, and the standby master station is forcibly reset and initialized.
A DLL request (request for collecting information from the master station) is issued to the master station. Based on this, the master station sends its own main memory 1 to the standby master station that issued the DLL request.
2 and sends the station start-up/operation information to that station, and also sends necessary information and start-up permission as a slave station. So, take the uke, C
The P IJ 11 receives this station start-up/operation information stored in the main memory 12 and writes it into the external storage medium 20 via the external storage medium read/write device 16 to update the old information. After this is completed, the CPU II of the slave station operates the slave station as a slave station based on the stored information stored in the main memory 12. Of course, the old information in the external storage medium 20 may be updated with new information after operating as a slave station.

Furthermore, if it is necessary to update the required information of the slave station as a new system in another slave station, the workstation 8 may issue a reset command to the slave station.

Note that when the workstation 8 gives a command to start the master station operation to the station 4, the CPU II of the station 4
executes the station startup program loaded into the main memory 12, but at that time, it automatically sends a forced reset command to each station in operation on the LAN without any operation from the workstation 8, and resets the other stations. It may also be configured to reset.

When this automatic forced reset command issuance function is provided, other stations are forcibly reset and initialized, and since station 4 has obtained operational management rights, these stations other than station 4 can request DLL requests (from the master station). Based on this, the master station recognizes the slave station that made the DLL request as a slave station, and recognizes that the station that made the DLL request is from the standby master station. If so, load it into its own main memory 12 and send new station activation/operation information to the DLL requesting station, as well as transmit necessary information as a slave station and activation permission,
In the slave station, this is received by the basic unit 13 via the conversion unit 14 in its own station, and the CPU II stores the received station startup/operation information in the main memory 12 and then sends it via the external storage medium read/write device 16. The information is written to the external storage medium 20 to update the old information. After this is completed, the CPU II of the slave station starts up its own station as a slave station based on the information in the main memory 12. ,, When the DLL requesting station is a station with only a slave station function, the master station transmits necessary information as a slave station and activation permission, and operates as a slave station.

In this way, if the station that received the DLL request was from the standby master station, the
The station activation/operation information stored in the external storage medium 20 of the LL requesting station is updated with new information, and the stations can be activated one after another. Therefore, when the LAN system is changed, information for station startup and network operation necessary for operating the LAN system as a standby master station as a master station based on new information is transferred to the standby master station in a remote location. You will be able to update and memorize the information without having to go to the office.

Note that in order to operate the external storage medium read/write device 16 in the station 4 to which the workstation terminal 8 is connected to update the contents of the external storage medium, first create new station startup/operation information on the workstation terminal 8. 1 from the workstation terminal 8 via the information-only cable (for parallel signals) 15b.
Part 10] Access CPU II from 5, and thereby
External storage medium read/write device 16 via PUII
make it work. In addition, in the case of a station that retains the master station function and does not have a terminal such as a workstation terminal, a forced reset command can be given from the workstation terminal, or the forced reset function can be added to the startup program of station 4 that is trying to join the LAN as a master station. ``The station 4 connected to the workstation terminal issues a station reset to each station on the LAN and requests a DLL,''
Pass new station startup/operation information from the master station,
The station startup/operation information that was loaded into the main memory 12 is loaded into the main memory 12, and the external storage medium read/write device 1B is operated using the initial external storage medium storage information update function. is transferred to the external storage medium 20 and updated.

In this way, for example, this system is constructed by adding a function to read and write the contents of an external storage medium within a station that has a master station function in a ring-type LAN, and it can also be operated as a master station. When the right is acquired, when an information collection request is received from a slave station, the station start-up/operation information is sent to the slave station, and when operating as a slave station, the station start-up/operation information received from the master station is sent to the slave station.
Since the operation information is updated and stored in the external storage medium, the station startup/operation information is stored in the external storage medium in the station having the master station function,
When this station is started up as a master station, other stations with master station functions can receive station startup and operation information from the station started up as a master station, and update and store it in their own external storage media. become. Therefore, if there is a change in the system and you want to update the station startup/operation information stored in the external storage medium of each station, you can start a new station in the external storage medium for one of the stations that has the master station function. - By storing the operation information and restarting the system so that this station becomes the master station, new station startup and operation information can be updated to the external storage media of other stations with master station functions. It can be memorized.

Therefore, when changing the system, etc., the station startup/operation information on the external storage medium of one station is rewritten, and that station is started as the master station.
In addition, for a remote station that has an external storage medium, by forcing a reset from the master station, the remote station will start up again from the beginning and perform the DLL request (the station with administrative rights will (has already been determined), the contents of the station's main memory and the contents of the external storage medium can be changed to new information, and a slave station with a master station function can self-register at any time with new station startup/operation information. It is now possible to restart the system and operate it using it as the parent station.
Information changes due to system changes can be made easily and in a short time.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with appropriate modifications within the scope without changing the gist thereof.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to transmit and update station activation/operation information to be held by a station with a master station function from one station, and therefore, the system Even when it becomes necessary to change the station activation/operation information due to a change, it is possible to provide a communication system that allows the station activation/operation information of each station to be updated in a short time without any effort.

[Brief explanation of the drawing]

The first factor is a schematic block diagram showing an embodiment of the present invention,
FIG. 2 is a schematic diagram of a LAN system using the device of the present invention. 1.5.6...standby master station, 2.3...
- Slave station, 4... Master station stage gin, 7a, 7b... communication path, 8A work station, ll... CPU. 12... Main memory, 13... Basic section, 14... Conversion section, 15... 110 parts, 1B... External storage medium read/write device, 17...
Bus, 20...Large capacity external storage medium.

Claims (1)

[Claims] A network is formed by connecting a plurality of stations with communication lines, and at least two of the stations have a master station function, and each station with the master station function has a An external storage medium is provided that stores information for station startup and network operation.
When the contents of this external storage medium are read at the initial stage and the first station starts up, it acquires the right to operate and manage the network as the master station, and other stations make requests to the master station to collect information. In response to this request, the master station sends the necessary information as a slave station to the requesting station, and upon receiving this, the requesting station operates as a slave station based on the received information, and the parent station in operation In a communication system in which when a station becomes abnormal, another station having the master station function becomes the master station, acquires the right to operate and manage the network, and operates the system, in which each station with the master station function a read/write control means for controlling read/write of stored information on the external storage medium; and a read/write control means for controlling read/write of stored information on the external storage medium; a first means for transmitting information to the requesting slave station; and updating information for starting the station and network operation sent from the master station to at least the external storage medium when operating as a slave station; and second means for controlling the read/write control means to cause the data to be stored.