JPH05252310A - Line switching device corresponding to isdn - Google Patents

Abstract

PURPOSE:To provide an ISDN corresponding line switching device for executing automatic switching between a private line and an ISDN line in the case of executing the line backup for a digital private line terminating equipment by an ISDN. CONSTITUTION:This line switching device is provided with a switching signal detection part 3 for detecting a line switching/connection request signal outputted from a DTE 20 and informing line switching to a control part 5 and a switching part 2 for switching the connection of a DTE 20 to a digital interface part 4 for converting the signal voltage level of an ISDN interface part 6 connected to the ISDN 23 or a DCE 21 connected to a private line 22. The switching part 2 is switched under the control of the control part 5 to select the ISDN 23 or the private line 22 as a using line.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active network or the like in which data communication is performed by using a line terminating device for a dedicated line, and when a failure occurs, a failure occurs between a digital interface and a digital interface via ISDN. The present invention relates to an ISDN-compatible line switching device that backs up a network.

[0002]

2. Description of the Related Art A conventional ISDN line switching device 7 is shown in FIG. In FIG. 2, an ISDN-compatible line switching device 7 includes a control unit 10 that operates based on a manual switching request from the outside, and an integrated service digital network (hereinafter ISDN).
Under the control of the ISDN interface unit 11 that transmits and receives digital signals to and from the DataT
A digital interface unit 9 for converting a signal voltage level between a signal for the terminal equipment (hereinafter, DTE) and a signal for the ISDN interface unit 11, and a line connected to the DTE are dedicated lines for a home side data line terminating device (hereinafter, DCE). And ISDN.

The digital data signal or digital control signal from the DTE is the V. 28
Is a signal having electrical characteristics based on. Also ISD
The signal level handled by the N interface unit 11 is TT
It is at the L level. Therefore, the digital interface unit 9 converts the digital data signal or the digital control signal from the DTE into a voltage level and outputs it to the ISDN interface unit 11, or the input signal from the ISDN interface unit 11 to the DTE digital data signal and the digital signal. The voltage level is converted into a control signal and output to the switching unit 8.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention Using the conventional ISDN-compatible line switching device 7 as described above,
As a countermeasure for communication failure in a digital leased line such as DX, when the line is backed up by ISDN, the line is switched manually by an operator. For this reason, it takes a long time to restore communication, and also requires an artificial operation, which is very troublesome.

An object of the present invention is to eliminate such problems of the prior art and to automatically and smoothly switch a used line between a digital leased line and an ISDN line. To provide.

[0006]

A first solution for solving the above problems is to provide an ISDN interface section 6 for performing a user / network interface with a comprehensive service digital network or an interface for a digital leased line. A switching unit for switching information signal connection between the external data terminal device and any of the external line terminators to be performed,
In an ISDN-compatible line switching device including a control unit that controls information signal connection switching of the switching unit based on a manual switching request from the outside, a line switching request signal or a switchback request signal output from the data terminal device is transmitted. A switching signal detection unit that detects reception and notifies the result, and an information signal connection switching of the switching unit is controlled by the notification signal of the switching signal detection unit, and the ISDN interface unit is provided with the service integrated digital network. And a control unit for controlling transmission of line switching information to the opposite station via the integrated service digital network. To do.

A second solving means of the present invention for solving the above-mentioned problems is to provide the control section according to the above-mentioned solving means to the above-mentioned IS.
A feature is added to control switching of information signal connection of the switching unit based on the line switching information received from the opposite station via the DN interface unit.

[0008]

[Operation] ISDN on remote side and local side
The corresponding line switching device is provided with a switching signal detecting unit that detects a line switching request signal or a line switching back request signal from the DTE and sends a command to the control unit that controls connection switching of the switching unit, and one of the local side or the like. If you want to switch the line by using the ISDN, the line switch is transmitted to the other side, such as the remote side, so you can automatically and smoothly switch the used line between the leased line and the ISDN. You can

[0009]

EXAMPLE An example of the present invention will be described below with reference to FIG. FIG. 1 is a block diagram showing the configuration of an ISDN-compatible line switching device 1 according to an embodiment of the present invention.
In FIG. 1, the data terminal Data T
terminal Equipment (hereinafter DTE) 2
0 is connected to the switching unit 2 so as to be able to send and receive digital data signals or digital control signals.
E) 21 is also connected so that it can send and receive digital data signals or digital control signals. Above D
A digital dedicated line 22 such as DDX is connected to the CE 21. The switching unit 2 is connected to the digital interface unit 4 and also connected to the control signal from the control unit 5 to be input. The digital interface unit 4 is an ISDN interface unit 6
The ISDN interface section 6 is connected to and receives various signals from the service integrated digital network (IS).
DN) 23. The ISDN interface section 6 is connected to the control section 5, and the ISDN 23
Call setup and call release to

Further, there is a switching signal detection unit 3 to which a line switching request signal or a line switching return request signal from the DTE 20 is input, and switching is performed so that a control signal corresponding to the request signal is output to the control unit 5. The signal detector 3 is connected to the controller 5.

In the above configuration, the local side, which is the local station, and the remote side, which is the opposite station, respectively, have the I of the present invention.
An SDN-compatible line switching device is installed and a dedicated line 22
And ISDN23 are connected. Then, in normal times, the switching unit 2 connects the DTE 20 and the DCE 21,
Digital dedicated line 22 such as DDX connected to DCE 21
It is assumed that digital data communication is performed with the opposite station using.

In such a state, if the DTE 20 determines that the local calling side has some trouble in the data communication on the digital leased line 22 and the communication is hindered, the ISDN 23 is used to connect the line. The DTE 20 uses a control signal on the digital interface (for example, data signal speed selection (hereinafter SDS)) for backup.
Is turned on, a switching request signal is output to the local ISDN-compatible line switching device 1. When the switching signal detection unit 3 of the ISDN-compatible line switching device 1 detects the switching request signal from the DTE 20, it notifies the control unit 5 of the result. The control unit 5 controls the ISDN interface unit 6 to make a call and a line switching request using the ISDN 23 to the remote side ISDN compatible line switching device which is the called side. Then, when confirming the notification that the line switching from the remote side ISDN-compatible line switching device to the remote side ISDN23 connection and the called side DTE is completed, the local side control unit 5 causes the digital interface of the DTE 20 and the ISDN interface. The switching unit 2 is controlled so that the unit 6 and the unit 6 are connected via the digital interface unit 4. After this, data communication by the backup network using ISDN 23 is performed.

Contrary to the above, the case where the DTE 20 issues a backup cancellation instruction to the ISDN-compatible line switching device 1 will be described. The DTE 20 outputs a line switching return request signal to the local side ISDN-compatible line switching device 1 by turning off a control signal (for example, data signal speed selection (hereinafter SDS)) on its own digital interface. The switching signal detection unit 3 on the local side is D
When the line switching return request signal from the TE 20 is detected, the result is notified to the control unit 5. The control unit 5 that has received this switching return request signal interrupts the data communication by the ISDN 23 and controls the ISDN interface unit 6 to control the ISDN.
The remote side ISDN compatible line switching device is notified of the line switching back instruction to the dedicated line via the DN 23. Then I
When confirming the completion notification of the backup release from the remote side through the SDN 23, the control unit 5 controls the switching unit 2 to control the digital interface of the DCE 21 and the DTE 2.
0 digital interface. Further, the ISDN interface section 6 is controlled to control the ISDN 23.
Is terminated and the backup cancellation is completed, and thereafter the digital communication using the dedicated line 22 is resumed.

Also, the ISD arranged on the remote called side
The operation of the N compatible line switching device will be described below. In the ISDN-compatible line switching device on the remote side, in response to the ISDN23 call from the local side, the IS on the remote side
When the control unit 5 of the DN compatible line switching device confirms the incoming call / switch request from the ISDN interface unit 6, the called side D
The switching unit 2 is controlled so that the TE digital interface and the ISDN interface unit 6 are connected via the digital interface unit 9. When the switching is completed, the ISDN interface unit 6 is controlled to notify the local side that the switching is completed. After that I
Data communication is performed by the backup network using the SDN 23.

When the backup cancellation notification from the local side is received via the ISDN interface 6, the control unit 5 of the remote side ISDN-compatible line switching device causes the ISDN
The data communication by 23 is interrupted, the switching unit 2 is controlled, and D
The CE digital interface and the DTE digital interface are connected. Further, after controlling the ISDN interface unit 6 to notify the local side of the backup cancellation, the ISDN 23 is disconnected and the backup cancellation of the network is completed. After this, the leased line 22
Return to data communication using.

As described above, the DTE is connected to the ISDN-compatible line switching devices on the remote side and the local side, respectively.
A switching signal detection unit 3 for sending a command to the control unit 5 that controls the connection switching of the switching unit 2 by detecting the line switching request signal or the line switching back request signal from the switching unit 2 is provided. When it is performed, since the line switching is transmitted to the other side such as the remote side via the ISDN, the used line switching between the dedicated line 22 and the ISDN 23 can be automatically and smoothly performed.

[0017]

As described above, according to the present invention, the conventional I
The SDN-compatible line switching device is provided with a switching signal detection unit that detects a line switching / switchback request signal from the DTE via the DTE digital interface and notifies the control unit of the signal.
Furthermore, according to the notification from the switching signal detection unit, a function for performing line switching and failback control was added to the control unit. Thus, when the local side ISDN-compatible line switching device is used to switch the line, the line switching is transmitted to the remote ISDN-compatible line switching device via the ISDN, and the line switching information received via the ISDN. Based on the above, the remote side control unit automatically switches the line, so switching the line used between the digital leased line and ISDN
It can be performed automatically and smoothly by the automatic detection of the terminal device.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 1,7 ISDN-compatible line switching device 2,8 Switching unit 3 Switching signal detection unit 4,9 Digital interface unit 5,10 Control unit 6,11 ISDN interface unit 20 Data terminal device 21 Line termination device 22 Dedicated line 23 ISDN

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location H04L 29/14

Claims (2)

[Claims] 1. An ISDN interface section 6 for performing a user / network interface with a comprehensive service digital network.
Alternatively, one of the external line terminators for interfacing the digital leased line, a switching unit for switching the information signal connection with the external data terminal device, and switching the information signal connection of the switching unit based on a manual switching request from the outside. In an ISDN-compatible line switching device including a control unit for controlling, a switching signal detecting unit that receives and detects a line switching request signal or a switchback request signal output from the data terminal device, and notifies the result, The information signal connection switching of the switching unit is controlled by the notification signal of the switching signal detection unit, and the ISDN interface unit is connected or disconnected to the opposite station via the integrated service digital network. , To transmit the line switching information to the opposite station via the integrated service digital network. ISDN corresponding line switching apparatus characterized by comprising said control unit for controlling the. 2. The control unit according to claim 1, further comprising a function of controlling information signal connection switching of the switching unit based on line switching information received from the opposite station via the ISDN interface unit. The IS according to claim 1,
A line switching device compatible with DN.