JP2916247B2 - ISDN terminal adapter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an ISDN terminal adapter connected between an ISDN line and a terminal.

(Prior Art) As shown in FIG. 2, a conventional ISDN terminal adapter 1a includes an ISDN interface unit 11, a call control / protocol conversion unit 12, a terminal interface unit 13, and a control unit 14. It is provided with the line 3 to perform outgoing / incoming control, incoming call control, signal exchange during a call, and the like.

However, since the terminal 2 is not always normal, the terminal 2 may not be able to respond to an incoming call and may be unable to communicate. In spite of such a situation, for an incoming call from the network side, the ISDN terminal adapter 1a sends
There is a problem that useless operations such as continued calling are performed, and a congestion state may be caused in some cases.

(Problems to be Solved by the Invention) As described above, according to the conventional ISDN adapter, the state of the terminal abnormality is not taken into consideration, and the useless call corresponding to the incoming call from the network side regardless of the terminal abnormality. In some cases, causing a congestion state in some cases.

The present invention has been made in order to solve the problems of the conventional ISDN terminal adapter, and the purpose is to
An object of the present invention is to provide an ISDN terminal adapter that accurately responds to terminal abnormalities and hardly causes congestion.

[Configuration of the invention]

(Means for Solving the Problems) An ISDN terminal adapter according to the present invention is connected between an ISDN line and a terminal, and monitors whether the terminal is abnormal or not. A terminal abnormality notification unit that, when the unit detects that the terminal is abnormal, sends a terminal abnormality notification to a calling side when an incoming call is received from the ISDN line.

Further, the ISDN terminal adapter according to the present invention is an ISDN terminal adapter.
A counterpart terminal state detection unit connected between the line and the terminal, which detects a terminal abnormality notification sent from the called side via the ISDN line, and the counterpart terminal state detection unit detects the terminal abnormality notification. In this case, there is provided a counterpart terminal error notification unit for notifying the terminal of an error of the counterpart terminal.

(Operation) According to the above-mentioned ISDN terminal adapter, an abnormality of the terminal is monitored, and in the case of an abnormality, the other party is notified when an incoming call is received, so that the other party can know the abnormality of the destination terminal.

Furthermore, according to the ISDN terminal adapter, the terminal abnormality notification sent from the other party is detected, and the terminal connected to the ISDN terminal is notified of the abnormality of the other terminal. Becomes

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram of one embodiment of the present invention. The ISDN terminal adapter 1 of this embodiment is provided with an ISDN interface unit 11, a call control / protocol conversion unit 12, a terminal interface unit 13, and a control unit 14, a terminal state monitoring unit 15, a terminal abnormality notification unit 16, A terminal state detection unit 17 and a partner terminal abnormality notification unit 18 are provided. The ISDN interface unit 11 performs synchronization control, speed control, and the like corresponding to the ISDN line 3. Terminal interface section 13 is CCITT, Recommendation, V24 / 28
, Or according to the CCITT recommendation X21 interface condition. The call control / protocol converter 12 separates and multiplexes the D channel and B channel of the ISDN line 3, performs call control based on the data of the B channel, and converts the protocol. The control unit 14 performs overall control such as timing control of each unit.

The terminal status monitoring unit 15 provided in the present embodiment
If the CCITT recommendation has a V24 / 28 interface, the control unit 14
In view of transmitting the CI signal to the terminal 2 and returning the ER signal in response to the
It monitors whether or not the ER signal is returned even if a predetermined time has elapsed after sending the signal, and sends a detection output to the control unit 14. Also,
If the terminal 2 has the CCITT recommendation, X21 interface, the control unit 14
In response to sending a R signal to the terminal 2 and returning a C signal in response to this when the terminal 2 is normal,
It monitors whether or not the C signal is returned even if a predetermined time has passed since the transmission of the R signal, and sends a detection output to the control unit 14. The control unit 14 receives the detection output and controls the terminal abnormality notification unit 16 to transmit a terminal abnormality notification. The call control / protocol converter 12 operates to send a terminal abnormality notification as a signal of the D channel.
It is transmitted from the ISDN interface unit 11 to the ISDN line 3.

The above is the abnormality monitoring operation performed by the ISDN terminal adapter 1 with respect to the terminal 2 on the receiving side. On the other hand, the ISDN terminal adapter 1 performs an abnormality notification operation of the terminal on the other side to the terminal 2 on the transmitting side. In the ISDN network, the terminal abnormality notification of the D channel is sent via the ISDN line 3. Therefore, this notification is received by the call control / protocol conversion unit 12 via the ISDN interface unit 11, taken out from the D channel, and given to the partner terminal state detection unit 17. The partner terminal state detecting unit 17 receives the terminal abnormality notification, detects that the partner terminal is abnormal, and provides a detection signal to the control unit 14. The control unit 14 gives an instruction to the partner terminal abnormality notification unit 18 to perform the abnormality notification. Therefore, the partner terminal abnormality notification unit 18 gives a drive signal to the display means 19 to perform a visual display indicating that the partner terminal is abnormal, to generate an alarm, and to notify the terminal 2 of the partner terminal abnormality. The terminal 2 includes a display unit (not shown), and performs a visual display corresponding to the notification. If the terminal 2 is a voice terminal (telephone or the like), a tone, music, or message indicating an abnormality may be generated from the receiver.

In the present embodiment, the components denoted by reference numerals 15 to 18 are provided independently, but they may be provided in the control unit 14. In addition, in view of the fact that the ISDN line 3 allows simultaneous calls by a plurality of terminals, the above-mentioned units (15 to 18) and the display means 19 are connected to the ISDN line
May be provided corresponding to the communication channel of (i). Further, the abnormality monitoring may be constantly performed.

〔The invention's effect〕

As described above, according to the present invention, it is possible to monitor the terminal for abnormalities and to notify when there is an incoming call in the case of abnormalities, so that the other party can know the abnormalities of the terminal, so that it is possible to cope with a line disconnection or the like. Yes, useless calls are not made and congestion is less likely to occur.

In addition, since the abnormality notification of the partner terminal is detected and the abnormality of the partner terminal is notified to the terminal, it is possible to cope with a line disconnection or the like at the terminal that has received the notification, and it is possible to reduce unnecessary congestion by eliminating unnecessary calls. effective.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a block diagram of a conventional ISDN terminal adapter. 1 ISDN terminal adapter 2 Terminal 3 ISDN line 11 ISDN interface unit 12 Call control / protocol conversion unit 13 Terminal interface unit 14 Control unit 15 Terminal state monitoring unit 16 … Terminal abnormality notifying section 17… Destination terminal state detecting section 18… Destination terminal abnormality notifying section 19… Display means

Claims (3)

(57) [Claims] A terminal abnormality monitoring unit connected between the ISDN line and the terminal for monitoring whether or not the terminal is abnormal, when the terminal abnormality monitoring unit detects that the terminal is abnormal, An ISDN terminal adapter, comprising: a terminal abnormality notification unit that sends a terminal abnormality notification to a calling side when an incoming call is received from the ISDN line. 2. An ISDN connected between an ISDN line and a terminal.
A counterpart terminal abnormality detection unit that detects a terminal abnormality notification sent from the called side via the DN line, and, when the partner terminal state detection unit detects the terminal abnormality notification, notifies the terminal of an abnormality of the partner terminal. An ISDN terminal adapter comprising: a partner terminal abnormality notification unit for notifying. 3. The ISDN terminal adapter according to claim 2, further comprising a display unit for displaying an abnormality when the partner terminal state detection unit detects a terminal abnormality notification.