JPS63131645A - Ineffective start preventing system for total dial network - Google Patents

Abstract

PURPOSE:To prevent an ineffective start from being repeated by the initial connection route by sending information to a pre-ceding exchange so as to allow the exchange to select other connection route if a succeeding connection route of an exchange relaying a call is faulty or all repeater lines are busy. CONSTITUTION:When a transmitter 22 detects a succeeding connection route of an exchange 2 or all busy state of relay lines, the information is informed to a faulty transmitter 23 from a faulty notice line 24. The transmitter 23 starts an exchange 1 via transmitters 21, 11 to make a call from the exchange 2 to the exchange 1, but if the exchange 1 does not receive a dial number within a prescribed time, it is discriminated that a succeeding connection route fault or all relay line busy to change the connection route to the exchange 4 into other connection route via the other exchange 3. Moreover, the 2nd connection route relaying the exchange 3 is selected at first and if the succeeding connection route of the exchange 3 or the all relay line busy takes place, the information is sent from the faulty transmitter 33 to the exchange 1 to change the connection to the 1st connection route.

Description

[Detailed Description of the Invention] [Summary] In a toll dial network having multiple connection routes,
If the subsequent connection route of the exchange that relays the call is faulty or all trunk lines are busy, the preceding exchange will be notified of this information and will be forced to select another connection route, and will be able to repeatedly invalidate the original connection route. This is to prevent activation.

[Industrial application field]

The present invention relates to a toll dial network, and in particular, when a subsequent connection route of an exchange that relays a call cannot be connected due to a failure, etc., the present invention prevents the previous exchange from repeatedly restarting the connection route. Concerning prevention methods.

FIG. 4 is an explanatory diagram of one configuration example of a toll dial network.

A toll dial network has multiple exchanges. For example, the fourth
As shown in the figure, exchange 1 has a first connection route connecting to exchange 4 via exchange 2, and a first connection route connecting to exchange 4 via exchange 3.
A second connection route connecting to the exchange 4 can be selected, and if the first connection route is blocked, the second connection route can be used to connect to the exchange 4.

However, in a simple link-by-link system like this example, if the downstream connection route of exchange 2 is in trouble or all trunk lines are busy, the upstream exchange does not know this condition, so the second connection route Even though it is empty,
An invalid restart continues for switch 2.

For this reason, it is desired to provide a method for preventing invalid activation of toll dial networks, which notifies the preceding exchange of information on failure of the subsequent connection route of the exchange or that all trunk lines are busy, and allows the exchange to select another connection route. .

[Conventional technology]

In conventional toll-dial networks, in the case of a simple link-by-link system, even if the downstream connection route of the switch that relays the call is faulty or all trunk lines are busy, the situation is not detected on the upstream switch side. Because I don't know, I continued to restart the selected connection route even though other connection routes were free, and I was unable to prevent invalid startup.

[Problem that the invention seeks to solve]

In the conventional method, if the downstream connection route of the selected exchange has a failure or a trunk line conversation is in progress, the preceding exchange will not connect to the selected There is a problem in which the connection route is repeatedly activated.

Measures to solve problem C] FIG. 1 is a block diagram of the principle of the present invention.

A plurality of exchanges 1, 2, 3.4 and a plurality of transmission devices LL12.21, 22, 31, 32.4 connecting these exchanges.
41 and 42 constitute a toll dial network having multiple connection routes.

The present invention includes fault transfer devices 23 and 33 on the ingress side of an exchange that relays calls, and fault transfer devices 23 and 3.
``3's rear transmission device 22.32 and failure transfer device 23゜3
3 are provided with fault notification lines 24 and 34, which solve the above problem.

[Effect]

When the transmission bag W 22 detects a failure in the downstream connection route of the exchange 2 or that all trunk lines are busy, the transmission bag W 22 notifies the failure transfer device 23 of the information through the failure notification line 24 .

The failure transfer device 23 that received the information transfers the information to the transmission devices 21 and 11.
Switch 1 is activated via , and a call is made from switch 2 to switch 1. However, if switch 1 does not receive dialed digits within a certain period of time, there is a problem with the subsequent connection route or all trunk lines are busy. Therefore, the connection route to the exchange 4 is changed to a connection route via another exchange 3.

The above is an explanation for the case where the first connection route that relays exchange 2 is selected first, but if the second connection route that relays exchange 3 is selected first, there is a failure in the subsequent connection route of exchange 3, or a trunk line If the problem occurs during a full call, the above information is transmitted from the fault transfer device 33 to the exchange 1 in the same way as above, and the connection is changed to the first connection route.

In this way, repeated invalid activations are prevented for exchanges that have faulty or trunk-busy downstream connection routes.

〔Example〕

The present invention will be specifically explained below with reference to illustrated examples.

FIG. 2 is a block diagram of a system for preventing invalid activation of a toll dial network according to an embodiment of the present invention, and FIG. 3 is an explanatory diagram of a connection route change processing procedure. The same reference numerals refer to the same objects throughout the design.

With reference to FIGS. 2 and 3, a description will be given of the subsequent connection route of the exchange 2, that is, the change of the connection route when there is a failure in the transmission equipment 22.41 and the transmission line or when all the trunk lines are busy.

If the transmission path or transmission device 22.41 etc. becomes a failure or the trunk line is all busy, the transmission path monitoring unit 221 of the transmission device 22
detects this, sends earth to the fault notification line 24, and operates the relay ^L of the fault transfer device 23. Here, VCC indicates a power supply.

The contact a1 of the relay AL sends the earth to the transmission device 21 via the contact di of the relay DL and the signal line SR, and the transmission device 121 transmits the control signal thereby to the transmission device 11,
The transmission device 11 converts the control signal and sends it to the signal line SR to operate the relay RG2 of the trunk 12 of the exchange 1, whose contact rg2 activates the route failure detection unit 14 of the central control device 13. Here, the signal vASS is activated,
A signal line for transmitting control signals such as dial pulses and a communication line TR represent four communication lines.

The route failure detection unit 14 detects that a call has been received from the downstream exchange (step S1), and starts timing (step S2).

Next, it is determined whether there is a dial during the above timing (step S3), and if there is no dial, the timing is terminated (step S4) to recognize that there is a connection route failure or that all trunk lines are busy (step S5). For example, the connection route is blocked and a different connection route is selected for subsequent connections (step S6).

If there is a dial, the redial digits are received by the normal connection means and the incoming call connection is established.

As explained above, if the downstream connection route of exchange 2 has a transmission path failure or all trunk lines are busy, calls that relay through exchange 2 cannot be connected, but connection from exchange 1 to exchange 2 is possible. .

In the normal case in this connection, the dialed digits are sent out on the signal line SS, passed through the fault forwarding device 23 and received on the trunk 24, and are analyzed by a central control device (not shown) to determine that they are internal numbers. and an incoming connection is made.

When the called subscriber answers, the signal is sent to the signal line SR of the trunk 24, the relay DL of the fault transfer device 23 is activated, and the contact di is sent to the transmission device 21 via the signal line SR.
The response signal is transmitted to the transmission bag 211, converted to a response signal, and sent to the trunk 12 via the signal line SR, thereby notifying the exchange 1 of the called subscriber's response. .

However, if the failure transfer device 23 sends information about a failure in the downstream connection route or a trunk line is busy to the exchange 1, the signal VASR has already been sent to the signal VASR at the contact a1 of the relay. In this case, contrary to the usual case, the signal line S
Control is performed to indicate the called party's response by disconnecting the ground at contact d1.

〔Effect of the invention〕

As explained in detail above, in the present invention, if the downstream connection route of the exchange that relays the call is in trouble or in trouble! If the ltl is busy, this information is transmitted to the 6th preceding exchange to select another connection route, thereby preventing repeated invalid activations for the original connection route.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a block diagram of a system for preventing invalid activation of a toll dial network according to an embodiment of the present invention, Fig. 3 is an explanatory diagram of the procedure for changing a connection route, and Fig. 4 1 is an explanatory diagram of one configuration example of a toll dial network. In the figure, 1 to 4 are exchanges, 11.12.21.22, 31.32, 4L42 are transmission devices, 23.33 is a failure transfer device, 24.34. indicates a fault notification line.

Claims (1)

[Claims] A plurality of exchanges (1, 2, 3, 4) and the exchanges (1,
A plurality of transmission devices (11, 12, 2, 3, 4) connecting
21, 22, 31, 32, 41, 42) and has multiple connection routes, a failure transfer device (
23, 33), the fault transfer device (23, 33) and its subsequent transmission device (
A failure notification line (24, 34) is provided between the exchanger (22, 32) and the failure notification line (24, 34).
2, 3) Notify the failure transfer device (23, 33) of the subsequent connection route failure or the information that all trunk lines are busy, and send the information from the failure transfer device (23, 33) to the preceding exchange (1). A system for preventing invalid activation of a toll dial network, characterized by transmitting information about a failure in a downstream connection route or when all trunk lines are busy.