JPH06259361A - Network control system - Google Patents

Abstract

PURPOSE:To perform control concentrically and remotely by controlling a network terminal device by utilizing a connection state signal between the network terminal device and a line concentrator to which the network terminal device is connected. CONSTITUTION:An analog circuit 18 which performs the transmission TX and reception RX of signals to and from the line concentrator through a LAN transceiver 17 is connected to a LAN controller 14, which serves as a circuit which detects link pulses from the received signal from the analog circuit 18. In this case, a link status monitoring circuit 15 which monitors an LINS signal generated by detecting the link pulses by the LAN transceiver 17 measures and reports the change and time of the state of a link status to a local CPU 10. The local CPU 10 receives the report from the link status monitoring part 15 each time the state changes and operates according to a determined rule.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network control system in a local area network (hereinafter abbreviated as "LAN").

[0002]

2. Description of the Related Art A LAN is a personal computer, workstation, host computer, or file system or input / output device (printer, display, It is an information communication system for connecting resources (scanners and the like) to each other through a common network so as to share resources, and has been rapidly spreading in recent years.

The standardization of this LAN protocol is "8" in the American IEEE (Institute of Electrical and Electronic Engineers).
The project named "02 Committee" is divided into 10 working groups (802.1 to 802.10) and is actively working on it. The main methods that have become the international standard for LAN are the CSMA / CD method (IEEE802.3) and the token bus method (IEEE802.3).
2.4), and Token Ring method (IEEE802.5).

The most popular of these is CS
The MA / CD method, which has many types,
"IEEE802.3 10BASE-T"("Star LA
(Also referred to as "N10") is common. This is a method of connecting each terminal device in a star shape by using a twisted pair cable and a concentrator (HUB) in a baseband with a data transmission rate of 10 Mbps on the trunk line, and is a standard star LAN. It can also be called the 10 Mbps version.

In this star LAN 10, a concentrator (H
It is stipulated that link pulse signals are asynchronously transmitted to each other as connection state signals for confirming mutual connection between segments such as UB) and terminal devices.

In the conventional method for controlling the network terminal device connected to such a LAN, it is necessary that each layer according to the seven layers of OSI as shown in FIG. A general method is to control by the application layer, which is the highest layer after communication in all layers.

[0007]

Therefore, it is necessary to separately prepare a control method for each network terminal device according to each network terminal device, and it is not possible to perform unified control for all network terminals. The present invention has been made in view of the above points, and makes it possible to control a network terminal device centrally and remotely from a control terminal device on a network regardless of the network protocol or OS. , And to enable the transmission of information from the network terminal device side.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a LAN (local area network).
There is provided a network control method characterized in that a network terminal device connected to the network terminal device is controlled by using a connection state signal between the network terminal device and a concentrator to which the network terminal device is connected.

The connection status signal is turned on at a predetermined time.
By turning on / off, the network terminal device can be controlled by a plurality of information. Further, the network terminal device turns ON / OFF the connection state signal.
By performing F, it is possible to notify the status from the network terminal device or to transmit information for controlling the network.

[0010]

According to the network control system of the present invention, a connection state signal (for example, a link pulse) between the network terminal device and the concentrator is transmitted from the control terminal device such as a personal computer connected to the LAN via the concentrator. It can be used to control the network terminal device. At that time, the network terminal device can be controlled by a plurality of information by turning on / off the connection state signal at a predetermined time. Further, by turning on / off the connection status signal on the side of the network terminal device, the status can be notified from the network terminal device and information for controlling the network can be transmitted.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 3 shows an example of connection of the star LAN 10, in which a plurality of concentrators (HUB) 2 are arranged on the network 1.
A and 2B are provided, and a plurality of control terminal devices 3A and 3B such as personal computers, a copy machine 4 and a printer 5, respectively, are provided in each of them.
Network terminal devices (I / O device devices) such as the scanner 6 and shredder 7 are connected in a star shape.

Concentrators include those that simply amplify and retime signals and output them to multiports, and intelligent hubs. The intelligent HUB, in addition to the concentrating function of the normal HUB, manages the traffic of the connected network terminal device (the amount of data flowing in the network), permits communication for each port, and turns on / off the link integrity function described later. Can be set, and it has already been commercialized by HP, AT & T, etc., and standardization is proceeding even in IEEE802.3.

The link integrity function is IEEE.
With 802.3 10BASET, the function of confirming mutual connection between the concentrator 2 and the paper terminals 4 to 7 is used to generate a link pulse at a predetermined interval (25ms to 50ms) as shown in FIG. The connection between segments is confirmed by asynchronously transmitting each other. According to the present invention, a link pulse, which is a connection state signal between the segments, is used by the link integrity function to perform a predetermined control on the network terminal device.

For example, a command is transmitted from the control terminal device 3A connected to the LAN of FIG. 3 to the intelligent concentrator 2A. This command is equivalent to controlling a conventional concentrator and is of application level. By transmitting a command to the concentrator 2A, it becomes possible to control the network terminal devices 4 and 5 connected to the concentrator 2A. Concentrator 2A
Decodes the command and controls the necessary ports. At this time, by controlling the link integrity function of the port, the network terminal device 4,
It becomes possible to transmit the control information to the communication device 5.

A circuit for detecting a link pulse is provided on the network terminal side, and when the state is monitored and transmission pulses from the other side are continuously received within a certain time, "Link safe" is set, and a connection state signal is generated as "link fail" when a transmission pulse cannot be received for a certain period of time. This function is usually possessed by commercially available LSIs for LAN transceivers and can be used.

It is possible to control the network terminal device in two modes, link fail and link safe, and this mode is turned on / off at a certain time interval.
By performing FF, it becomes possible to control the network terminal device in a plurality of modes.

FIG. 1 is a block diagram of the essential parts of the hardware of the network terminal device in that case, and FIG. 2 shows the processing flow. In FIG. 1, a local CPU 10 is connected to a system bus 12 via a bus I / F control unit 11, a memory (ROM, RAM) 13, a LAN controller 14, and a link status monitoring unit 15 and C.
It is connected by the PU bus 16.

The LAN controller 14 transmits a signal to and from the concentrator via the LAN transceiver 17 (T
x) and reception (Rx), an analog circuit (transmission / reception circuit) 18 is connected, and the LAN transceiver 17 also serves as a circuit for detecting a link pulse from a signal received by the analog circuit 17. In this example, LINS generated by link pulse detection by the LAN transceiver 17
The link status monitoring unit 15 that monitors the signal (link fail / link safe status signal) measures the change in the status of the link status and the time, and notifies the local CPU 10.

The local CPU 10 receives a notification (interruption) from the link status monitoring unit 15 each time a state change occurs, and operates according to a predetermined appointment. The notification to the network terminal device is sent from the local CPU 10 to the system side via the bus I / F control unit 11 and the system bus 12, for example. The local CPU 10 of the network terminal device shown in FIG.
The processing by will be described according to the flowchart of FIG.

The link status monitoring unit 15 measures and notifies the local CPU 10 of the changed mode and time, for example, by an interrupt process when the link safe state is changed to the link fail state. In addition, the maximum measurement time is determined to be, for example, 1 sec, and when it is longer than that, the local CPU 10 is notified so that it can be distinguished from segment down (cable disconnection or non-connection) and the end of the notification pattern can be detected.

When the local CPU 10 starts the interrupt processing, it is first determined whether or not there is a link failure, and if it is a link failure, then it is determined whether or not it has continued for 1 sec or more. If 1 second or more has elapsed, the segment down is notified to the user and the process returns to the main routine (not shown). If it does not continue for 1 sec, it returns as a notification pattern.

If it is not a link fail, it is link safe, but it is judged whether or not it has continued for 1 second or more, and if it continues, the notification pattern end processing is performed, and the notification pattern is decoded and processed. I will return later.
If it has not continued for 1 sec, it is registered as a notification pattern and the process returns. With the above hardware and the program processing by the local CPU 10, it becomes possible to transmit the control information to the network terminal device by controlling the link integrity function.

In a commercially available LSI for LAN transceiver, it is possible to switch between sending and not sending the link pulse. By using this mode, it is also possible to control the link integrity function from the network terminal device side and transmit the status of the network terminal device and information for network control. In that case, by controlling the LINKM signal (link mode setting signal) output from the link status monitoring unit 15 to the LAN transceiver 17 according to an instruction from the local CPU 10 in FIG. 1, and transmitting it from the analog circuit 18 to the concentrator. realizable.

Here, the basic embodiment of the present invention will be concretely described again with reference to the LAN of FIG. Link pulse is turned ON / OF by using the management function of each port of the concentrators 3A and 3B which are intelligent HUBs.
Then, the network terminal devices 4 to 7 having the link pulse detection circuit and the transmission circuit are controlled. On the side of the network terminal device, when the link pulse from the side of the concentrator is turned on, the main power supply is turned on to be in a usable state. When the link pulse is turned off, the main power supply is turned off and the standby state is entered.

On the concentrator side, it is detected that the network terminal device is in the enabled state (usable state) by turning on the link pulse from the network terminal device side, and it is disabled by the link pulse being turned off. (In use) can be detected.

Therefore, when the control terminal device 3A wants to turn on the power of the copy machine 4, the control terminal device 3
Link pulse O from A to port 1 of concentrator 3A
Set N. With this setting, a link pulse is transmitted from the port 1 of the concentrator 3A, and the copy machine 4 detects it and turns on the main power supply. Then, when the copy machine 4 becomes available after the warm-up time, the link pulse is turned on to turn on the port 1 of the concentrator 3A.
To notify.

The control terminal device 3A looks at the status of the port 1 and detects that the copy machine 31 is available. Also, when the power of the shredder 7 is turned on from the control terminal device 3A, the link pulse ON is set to the port 4 of the concentrator 3B. Since the concentrator has a unique MAC address, it is distinguished on the network.

[0028]

As described above, according to the network control method of the present invention, the control of the network terminal device is controlled by the control terminal device on the local area network (LAN) regardless of the network protocol and OS. , Can be performed centrally and remotely using a connection status signal (for example, a link pulse) between the network terminal device and the concentrator.

Further, by patterning the information transmission method by the connection status signal, it becomes possible to control the network terminal device in a plurality of states, and the system can be provided with redundancy. Further, the network terminal device side can also transmit control information such as status notification and urgent request processing to the control terminal device side.

[Brief description of drawings]

FIG. 1 is a block diagram of essential parts of hardware of a network terminal device in an embodiment of the present invention.

FIG. 2 is a flowchart of interrupt processing by a local CPU 10 shown in FIG.

FIG. 3 is an explanatory diagram showing a connection example of a star LAN 10 embodying the present invention.

FIG. 4 is a diagram for explaining a link integrity function for confirming mutual connection between a concentrator (intelligent HUB) and a network terminal device.

FIG. 5 is an explanatory diagram of 7 layers of OSI.

[Explanation of symbols]

1: Network 2, 2A, 2B: Concentrator (HU
B) 3A and 3B: control terminal device 4: copy machine 5: printer 6: scanner 7: shredder 10: local CPU 14: LAN controller 15: link status monitoring unit 17: LA
N transceiver 18: analog circuit (transceiver circuit)

Claims (3)

[Claims] 1. A network control method, wherein a network terminal device connected to a local area network is controlled by using a connection status signal with a concentrator to which the network terminal device is connected. 2. A plurality of pieces of information are output by turning on / off a connection state signal between a network terminal device connected to a local area network and a concentrator to which the network terminal device is connected at a predetermined time. A network control method characterized by being controlled by. 3. A network terminal device connected to a local area network turns ON / OF a connection status signal with a concentrator to which the network terminal device is connected.
A network control system characterized in that the status notification or the information for network control is transmitted from the network terminal device by performing F.