JPH1174988A - Terminal network controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always and immediately issue emergency notification from a gas meter connected to a terminal network controller when the terminal network controller is fitted to an ISDN public line. SOLUTION: A line terminating means 2 which is connected to the interface L1 point of the ISDN pubic line, terminates the line, converts input/output signals as S/T points and inputs/outputs them as internal S/T points, a terminal communication means 4 executing communication with the ISDN public line through the internal S/T point and an S/T point cut means 5 supplying the S/T point to outside through an external input/output terminal and cut-controls the external input/output terminal and the internal S/T point are provided. Since the S/T point bus of down stream can be cut by the S/T point cut means 5 at the time of the call from the terminal equipment, a communication channel can be secured without fail.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal network control device for communicating terminal devices such as meter reading meters and equipment with a remote management device via an ISDN public line.

[0002]

2. Description of the Related Art Automatic meter reading of an energy supply management device (for example, a gas meter, a water meter, an electric power meter) from a remote management device using a telephone network, notification of a gas leak to the remote management device, and failure notification of equipment. Systems for performing remote diagnosis and the like are becoming widespread.

[0003] Further, ISDN telephone lines have begun to spread, and introduction to general households for accessing personal computer communication and the Internet has also become active. The general system configuration is such that a digital line terminator (hereinafter referred to as a DSU) is connected to a two-wire metal cable drawn from the ISDN public line to the house via a protector, and transmission such as two-wire to four-wire conversion is performed. The end of the road is done and IS
Connect a digital telephone for DN,
An adapter (hereinafter referred to as TA) is connected to perform protocol conversion, and is connected to a terminal device such as a personal computer using an RS-232C cable or the like. At NTT (Nippon Telegraph and Telephone Corporation), the reference point is the interface from the protector to the DSU. The reference point is the interface from the DSU to the telephone or TA. The reference point is the interface from the S / T, and the interface from the TA to the terminal equipment such as a personal computer. Called R. In addition, S /
The T point is an IS defined in Recommendation I.411.
DN user-network interface point, R point is ITU
-An existing user / network interface point defined in T Recommendation V, X series, etc.

An example of communication between a remote management device and a terminal device via an ISDN public network is disclosed in JP-A-6-24.
No. 4983 discloses an automatic meter reading system. The system is a terminal network control device connected to an S / T point of a customer house, a terminal device such as a gas meter connected to the terminal network control device, and a remote management device installed in a gas company or a security company. It consists of a center device. Then, the center device performs communication by B-channel circuit switching or B-channel or D-channel packet switching via the ISDN public line, and reads data from the terminal device.

[0005] In addition, in the ISDN public line, the power that can be transmitted and received from the line is 1000 mW per line at the LI point.
The power supplied to the S / T point bus is 400 mW (the actual usable amount is about 300 mW in the DSU in consideration of the power loss, and 38 mW for the designated terminal of the S / T point bus).
0 mW and 20 mW for other terminals). If the operating power of the communication terminal exceeds this, it is necessary to supply an external power supply such as a commercial power supply or a battery.

[0006]

The above-mentioned conventional system has the following problems.

(1) There is a case where there is no available channel when another communication terminal of the customer's house is in use, so that a report from a terminal device connected to the terminal network control device cannot be transmitted immediately.

(2) When an automatic call is made from a terminal device connected to the terminal network control device, there is a case where there is no available channel when another communication terminal of the customer's house is in use, so that the terminal device reports Cannot be prioritized.

(3) At the time of an emergency call from a terminal device connected to the terminal network control device, there is a case where there is no available channel when another communication terminal of the customer's house is in use. May be delayed.

(4) At the time of an automatic call from a terminal device connected to the terminal network control device, two B channels may be used in another communication terminal of the customer's home. Cannot be used.

(5) Unless the terminal network controller is designated as a designated terminal, almost no power can be transferred from / to the line except for the DSU portion. If power cannot be supplied from the commercial power source during a power outage, the terminal network controller does not operate.

(6) The communication terminal connected to the S / T point has no communication priority, and if another terminal is using the communication channel, it must wait until the channel is released.

[0013]

SUMMARY OF THE INVENTION According to the present invention, there is provided an ISDN public line interface LI.
Line termination means for terminating the line and converting the input / output signal as an S / T point signal to input / output as an internal S / T point;
Terminal communication means for communicating with an ISDN public line via a point, providing the internal S / T point to an external through an external input / output terminal, and connecting the external input / output terminal to the internal S / T point cutting means for controlling cutting with the S / T point.

According to the above invention, the downstream S / T point bus can be disconnected by the S / T point disconnecting means, so that a communication channel for the terminal device can always be secured.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention connects to an interface LI point of an ISDN public line, terminates the line and
Performs input / output signal conversion as a / T point signal and performs internal S / T
Line terminating means for inputting / outputting as a point, terminal communication means for connecting a terminal device to communicate with an ISDN public line via the internal S / T point, and connecting the internal S / T point via an external input / output terminal S / T point disconnection means for providing an S / T point to the outside and controlling disconnection between the external input / output terminal and the internal S / T point. And S /
The communication terminal connected to the S / T point downstream of the terminal network control device can be disconnected from the line by the T point disconnecting means.

Further, the S / T point disconnecting means includes an opening / closing means for disconnecting each signal line at the S / T point in response to a disconnection request signal from the terminal communication means. A communication channel can be secured by disconnecting a communication terminal connected to the S / T point downstream of the terminal network control device from the line at the request of the terminal communication means.

Further, the terminal communication means sends a disconnection request signal to the S / T point disconnection means upon receiving a predetermined signal from the terminal device. Then, a communication channel can be secured by disconnecting the communication terminal connected to the S / T point downstream of the terminal network control device from the line at the request of the terminal device.

Further, the terminal communication means requests communication using the B channel to the ISDN public line, and
Upon receiving a notification indicating that the B channel cannot be used from the N public line, a disconnection request signal is sent to the S / T point disconnecting means. If all B channels are occupied at the time of calling the terminal device, the B channel can be secured by disconnecting the communication terminal connected to the S / T point downstream of the terminal network control device from the line.

Further, the terminal communication means detects the start of communication of the terminal device, sends a disconnection request signal to the S / T point disconnection means, and operates on battery power. A terminal communication relay means for relaying communication with an ISDN public line via a point T, and supplying power to at least the terminal communication relay means with power supplied from a commercial power supply to detect a loss of power of the commercial power supply Then, after the external input / output terminal is disconnected by the S / T point disconnecting means, the power is transmitted to and received from the ISDN line to supply the power to the line termination means and the terminal communication relay means. It is provided with a supply means. Then, even at the time of a power failure, the S /
By disconnecting the communication terminal connected to the point T from the line, power from the line can be secured.

Further, a plurality of terminal communication means for communicating with the ISDN public line by connecting the terminal equipment, and another terminal communication means when the terminal equipment connected to the terminal communication means having higher priority performs communication. If the connected terminal device is using all the communication channels, at least one of the communication channels in use is released and communication between the terminal device connected to the terminal communication means having a higher priority and the ISDN public line is performed. It is provided with line communication means for performing. And the communication of the terminal device connected to the terminal communication means of high priority can always be performed immediately.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram of a terminal network control apparatus according to Embodiment 1 of the present invention. In the figure, reference numeral 1 denotes a terminal network control device. Reference numeral 2 denotes a line terminating means which is connected to an interface LI point of an ISDN public line to terminate the line and perform input / output as an internal S / T point by S / T point conversion. Reference numeral 3 denotes a gas meter as a terminal device. Reference numeral 4 denotes a terminal communication unit which communicates with the ISDN public line via the internal S / T point by connecting to the gas meter 3. S / T point disconnecting means 5 provides an S / T point for connecting an internal S / T point to a telephone 6 or a terminal adapter 7 as an external communication terminal via an external input / output terminal, and also provides an S / T point. The external input / output terminal at point T is disconnected from the internal S / T point.

With the above configuration, when it is desired to perform communication with the gas meter 3, the S / T point disconnecting means 5 is externally operated by a switch or the like to disconnect the downstream S / T point bus from the terminal network control device. Thus, regardless of the state of the telephone 6 and the terminal adapter 7 connected downstream, the gas meter 3 can immediately perform communication via the ISDN public line.

The operation of the S / T point disconnecting means is not limited to an external operation, and may be activated by detecting a disaster such as an earthquake in the terminal network control device.

The signal format of the internal S / T point is as shown in ITU-T I.430, and the electrical characteristics may be a three-wire system consisting of transmission, reception and ground signal lines as TTL levels. S / T in case
Within the point cutting means, the regular ITU-T I.430
It is sufficient to convert the signal into a four-wire system composed of transmission and reception signals having the electrical characteristics shown in FIG.

(Embodiment 2) FIG. 2 is a block diagram of a terminal network control apparatus according to Embodiment 2 of the present invention. In the figure, the difference from the first embodiment is that the S / T point disconnecting means 5 is
The S / T point disconnecting means 5 is provided with an opening / closing means 8 for physically disconnecting the S / T point in that each signal line at the S / T point is disconnected in response to a disconnection request signal from the CPU.

With the above configuration, when the terminal communication means 4 is notified that the gas meter 3 will make a call, the terminal communication means 4 transmits a disconnection request signal to the S / T point disconnection means 5, and
The T point disconnecting means 5 opens the opening / closing means 8 to open the terminal network control device 1.
Disconnect the S / T point bus downstream of. For this reason, the call request from the gas meter 3 is always successful and communication via the ISDN public line can be immediately performed.

Although a physical switch is shown as the opening / closing means in FIG. 2, the same effect can be obtained by logically disconnecting using a transistor switch or the like.

Also, when the terminal communication means receives the start of communication of the center device to the terminal device via the ISDN public line via the internal S / T point, a disconnection request is issued to the S / T point disconnection means. It is also possible to send a signal, whereby communication of the terminal device can be given top priority for both transmission and reception.

(Embodiment 3) The third embodiment of the present invention is different from the second embodiment in that when the terminal communication means 4 receives a signal determined as a gas leak notification request from the gas meter 3, the S / T point disconnection means 5 is that a disconnection request signal is sent to the control unit 5. FIG. 3 is a flowchart of processing in the terminal communication means when a terminal call is requested from the gas meter in the terminal network control device according to the third embodiment of the present invention.

According to the above configuration, when the terminal communication means 4 is notified that the gas meter 3 will make a call, the terminal communication means 4 checks whether the call request from the gas meter 3 is an urgent gas leak report request. (101). If the request is a gas leak report request, a disconnection request signal is sent to the S / T point disconnecting means 5 (102). Next, a call is made to the communication center device (103). If there is an available B channel in the ISDN public line (104), it connects to the center device and starts communication (106). If the call request from the gas meter does not require urgency, such as a regular call, the disconnection request to the S / T point disconnection means 5 is not issued and the call to the communication center device is made. A call is made (103). In this case, B in the downstream S / T point bus
If both channels are used, it is notified from the ISDN public line that there is no usable B channel (104), and a standby for a predetermined time of about one minute is performed (10).
5). Thereafter, a call is made to the center device again (10
3).

As described above, in an urgent report, S / T
In order to cut the downstream S / T point bus by the point cutting means,
You can always report immediately.

(Embodiment 4) The fourth embodiment of the present invention is different from the second embodiment in that the terminal communication means 4 requests the ISDN public line for communication using the B channel and
When a notification indicating that the B channel cannot be used is received from the N public line, a disconnection request signal is sent to the S / T point disconnecting means 5. FIG. 4 is a flowchart of processing in the terminal communication means when a terminal call request from the gas meter of the terminal network control device according to the fourth embodiment of the present invention.

In the above configuration, when the terminal communication means 4 is notified that the gas meter 3 will make a call, the terminal communication means 4 makes a call to the center device which is the communication destination (20).
1). If there is an available B channel in the ISDN public line (202), it connects to the center device and starts communication (204). However, both B channels are used in the downstream S / T point bus and the ISDN
When it is notified from the public line that there is no usable B channel (202), a disconnection request signal is sent to the S / T point disconnecting means 5 (203). Thereafter, a call is made to the center device again (103).

As described above, if the communicable B channel is not vacant, the S / T point disconnecting means disconnects the downstream S / T point bus, so that a call can be made from the terminal device without fail.

(Embodiment 5) FIG. 5 is a block diagram of a terminal network control apparatus according to Embodiment 5 of the present invention. In the figure, the difference from the second embodiment is that the commercial power supply (AC100V) and the ISD
N is provided with a power supply unit 9 that supplies power to each unit from the power supplied from the N public line and notifies the terminal communication unit 4 when the power loss of the commercial power supply is detected. When the communication start of the gas meter 3 is detected,
A terminal communication detecting means 10 for sending a disconnection request signal to the / T point disconnecting means 5, a terminal communication relaying means 11 operated by a commercial power supply, and relaying communication between the gas meter 3 and an ISDN public line via an internal S / T point; It consists of.

In the above configuration, the terminal network control device 1 is normally connected to a commercial power supply of AC 100 V and connected to the line termination unit 3, the terminal communication unit 4, and the S / T point disconnecting unit 5 by the power supply unit 9. Power is being supplied. However, when a power failure or disconnection of the AC outlet occurs, the power supply unit 9 notifies the terminal communication detection unit 10 of the terminal communication unit 4 that commercial power has been lost. The line termination means 3 is a power supply means 9
When power is no longer supplied, operation is performed using line power. Further, the terminal communication detecting means 10 operates on the battery power supply after being notified of the disappearance of the commercial power, and transmits a disconnection request signal to the S / T point disconnecting means 5 when notified of the calling request from the gas meter 3. The S / T point disconnecting means 5 also operates on battery power after being notified of the disappearance of the commercial power, and disconnects the S / T point bus downstream of the terminal network control device 1 when notified of the disconnection request signal. For this reason, there is no fear that another communication terminal uses the line power, and the power supply unit 9 supplies and receives 400 mW of power from the ISDN public line to supply operating power to the terminal communication relay unit 11 of the terminal network control device 1. . Therefore, the terminal network control device 1 does not run out of power because it performs communication with the gas meter 3 via the ISDN public line.

It should be noted that the terminal communication means may send the S / T point disconnection request only at the time of an emergency call request from the gas meter, or even at the time when the power supply means is notified of the loss of commercial power. Good.

Further, since the line terminating means functions as a DSU, the power supplied from the commercial power supply can always be reduced if the line terminating means is operated by transmitting and receiving about 300 mW from the line even in normal times.

Although a battery power supply is used as an operating power supply after the commercial power of the terminal communication detecting means and the S / T point disconnecting means is lost, the battery is not limited to a primary battery such as a dry battery or a lithium battery. The same effect can be obtained by using a secondary battery or a solar battery that is charged by electric power or line power.

(Embodiment 6) FIG. 6 is a block diagram of a terminal network control apparatus according to Embodiment 6 of the present invention. In the figure, a first terminal communication means 4a is connected to a gas meter 3 to
Communicates with the public line. The second terminal communication means 4 b
The telephone 6 is connected at the / T point to communicate with the ISDN public line. The third terminal communication means 4c connects with the terminal adapter 7 at the S / T point and communicates with the ISDN public line. The line communication unit 12 sets and stores the communication priority of the terminal communication unit 4 in the first, second, and third order, and the terminal device connected to the terminal communication unit 4 having the higher priority performs communication. Sometimes, if the terminal device connected to the other terminal communication means 4 is using all communication channels, at least one of the communication channels in use is released and the terminal connected to the terminal communication means 4 having a higher priority. The device communicates with the ISDN public line.

In the above configuration, the line communication means 12
When the call request is notified from the gas meter 3 via the first terminal communication means 4a, the second terminal communication means 4b and the third
The communication status of the terminal communication means 4c is confirmed, and if both of the B channels are in use, the third terminal communication means 4c having a low priority is disconnected. As a result, one channel of the B channel is opened, so that the gas meter 3 calls the ISDN public line via the first terminal communication means 4a and communicates with the center device.

As described above, a terminal device connected to a terminal communication unit having a higher priority can always obtain a communication channel even if a terminal device connected to a terminal communication unit having a lower priority is communicating.

Note that it is also possible to set only the highest priority terminal communication means without setting the priority order of the terminal communication means in order.

[0045]

According to the terminal network control device of the present invention as described above, the following effects can be obtained.

(1) By disconnecting the S / T point bus downstream of the terminal network control device by the S / T point disconnecting means, other communication terminals of the customer's house are disconnected from the S / T point bus.
The terminal device connected to the terminal network control device can always perform call communication.

(2) When an automatic call is made from a terminal device connected to the terminal network control device, S / T is performed by the terminal communication means.
S / T downstream from terminal network controller by notifying to point disconnection means
Since the point bus is disconnected, the call from the terminal device can always be given priority even when another communication terminal of the customer's house is in use.

(3) At the time of an emergency call from a terminal device connected to the terminal network control device, S / T is performed by the terminal communication means.
S / T downstream from terminal network controller by notifying to point disconnection means
Since the point bus is disconnected, the emergency call from the terminal device is not delayed even when another communication terminal of the customer's house is in use.

(4) When two B channels are used in another communication terminal of the customer's home at the time of automatic calling from a terminal device connected to the terminal network control device, S / T is performed by the terminal communication means. The terminal disconnects the S / T point bus downstream from the terminal network controller by notifying the point disconnecting means.
Channels are always available.

(5) Even if the terminal network control device is not designated as a designated terminal, if power cannot be supplied from the commercial power source during a power failure, the S / T point disconnecting means is used when the terminal device connected to the terminal network control device communicates. To disconnect the S / T point bus downstream from the terminal network controller, the terminal network controller can operate by transmitting and receiving line power.

(6) Since the communication priority of the communication terminal connected to the terminal network control device is present, even if another terminal is using the communication channel, the communication of the terminal device having a higher priority always secures the communication channel. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram of a terminal network control device according to a first embodiment of the present invention;

FIG. 2 is a block diagram of a terminal network control device according to a second embodiment of the present invention;

FIG. 3 is a flowchart of a process performed by a terminal communication unit at the time of a terminal call request of a gas meter of a terminal network control device according to a third embodiment of the present invention.

FIG. 4 is a flowchart of a process performed by a terminal communication unit at the time of a terminal call request of a gas meter of a terminal network control device according to a fourth embodiment of the present invention.

FIG. 5 is a block diagram of a terminal network control device according to a fifth embodiment of the present invention.

FIG. 6 is a block diagram of a terminal network control device according to a sixth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Terminal network control device 2 Line termination means 3 Gas meter (terminal device) 4 Terminal communication means 5 S / T point disconnection means 6 Telephone 7 Terminal adapter 8 Opening / closing means 9 Power supply means 10 Terminal communication detection means 11 Terminal communication relay 12 Line communication means

Claims (6)

[Claims] 1. Line termination means for connecting to an interface LI point of an ISDN public line, terminating the line, performing input / output signal conversion as an S / T point signal, and inputting / outputting as an internal S / T point, and a terminal. Terminal communication means for connecting a device to communicate with an ISDN public line via the internal S / T point, and providing the internal S / T point to the outside via an external input / output terminal A terminal network control device comprising: S / T point disconnection means for controlling disconnection between the external input / output terminal and the internal S / T point. 2. The terminal network control device according to claim 1, wherein the S / T point disconnecting means includes opening / closing means for disconnecting each signal line at the S / T point in response to a disconnection request signal from the terminal communication means. 3. The terminal network control device according to claim 2, wherein the terminal communication means sends a disconnection request signal to the S / T point disconnection means when receiving a predetermined signal from the terminal device. 4. The terminal communication means, upon requesting communication using the B channel to the ISDN public line and receiving a notice indicating that the B channel cannot be used from the ISDN public line, sets the S / T
3. The terminal network control device according to claim 2, wherein a disconnection request signal is sent to the point disconnection means. 5. A terminal communication means for detecting the start of communication of a terminal device, transmitting a disconnection request signal to an S / T point disconnection device, and operating on battery power, a terminal communication detecting device, and a terminal communication device. A terminal communication relay means for relaying communication with an ISDN public line via a point T, and supplying power to at least the terminal communication relay means with power supplied from a commercial power supply to detect a loss of power of the commercial power supply Then, after the external input / output terminal is disconnected by the S / T point disconnecting means, the power is transmitted to and received from the ISDN line to supply the power to the line termination means and the terminal communication relay means. 3. The terminal network control device according to claim 2, further comprising a supply unit. 6. A plurality of terminal communication means for connecting a terminal device to communicate with an ISDN public line, and a plurality of terminal communication devices connected to a terminal communication device having a higher priority when another terminal communication means performs communication. If the connected terminal device is using all the communication channels, at least one of the communication channels in use is released and communication between the terminal device connected to the terminal communication means having a higher priority and the ISDN public line is performed. A terminal network control device provided with a line communication means for performing communication.