JPH05244250A - Virtual processing private line system in isdn - Google Patents

Abstract

PURPOSE:To increase number of private lines as required, to reduce number of usual private lines and to back up the private line on the occurrence of a fault. CONSTITUTION:A terminal equipment 1 makes dialing to a terminal equipment 16 and when a private line trunk circuit 3 is busy, an idle channel is selected and a call event is informed to a central controller 8 to set an establish request of a virtual processing private line. The central controller 8 makes dialing to an ISDN 17 by using a number of an opposite station registered in a main storage device 18. A central controller 14 of a called station executes the incoming call processing to a voice compression trunk 12 and the voice compression trunk 12 replies the call automatically to allow a primary group interface circuit 10 to give a reply to the ISDN 17. The central controller 8 connects the channel switch of the voice compression trunk 6 from a primary group interface 4 to establish the virtual processing private line through the ISDN 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a private exchange having an I interface and, more particularly, to a virtual private line system in an ISDN network for setting a virtual private line using the ISDN network.

[0002]

2. Description of the Related Art Conventionally, a leased line is a line used only between opposite private exchanges and is a direct connection line not connected to a public network. This dedicated line uses a large number of lines so that it will not be blocked even during the busiest hours in consideration of the traffic between the private exchanges facing each other.

[0003]

The operation status of the above-mentioned conventional private exchange using the leased line is several hours per day even during the busy hour, and there are many non-operation stations with no traffic at midnight. There are also stations where traffic is concentrated on specific days of the week. In this case, the dedicated line cannot be used as much as necessary only during busy hours, although it depends on the state of each station. Therefore, there is a problem that the number of leased lines in constructing the network must be contracted and used in consideration of busy hours.

The present invention solves the problems in the prior art as described above, and sets a virtualized leased line through the ISDN network only when traffic is high and a dedicated line overflow occurs. An object of the present invention is to provide a virtualized leased line system in an ISDN network that can increase the number of leased lines, reduce the number of ordinary leased lines, and perform backup in the event of a leased line failure.

[0005]

In order to achieve the above object, the present invention is provided in a private exchange having an I interface, sets a virtual private line through an ISDN network when a line overflow call occurs, and a virtual private line. Is established,
One channel among the multiple channels multiplexed is used as a signal path,
A virtualized leased line system in an ISDN network that uses another channel as a communication path, and a 16 kbps signal of 64 kbps PCM exchanged through an exchange time division switch.
Compressed to sMPC signal or 32kbps ADPCM signal and output as multiplexed 64kbps signal, or separated and demodulated multiplexed signal to 64kbpsP
A voice compression / separation / demodulation means for outputting a CM signal and a 64 kbps PCM for connecting to the exchange time division switch.
When a signal input / output channel is selected, an automatic call is automatically issued to set a voice compression / separation / demodulation means in the opposite exchange through the ISDN network and a virtualized dedicated line for communicating multiplexed signals. And the ISDN network connected through the voice compression / separation / demodulation means and the exchange time division switch at the time of an incoming call for establishing a virtualized leased line from the ISDN network. And a virtual private line connecting means for connecting the virtual private line and the virtual private line. Also, if necessary, monitor the usage status of the multiplexed channels while establishing the virtual leased line,
The virtualization dedicated line releasing means is provided for releasing the virtualization dedicated line when there is no channel used other than the signal path for a certain period of time.

[0006]

The virtualized leased line system in the ISDN network of the present invention having such a configuration is necessary because the virtualized leased line is set through the ISDN network only when the traffic is high and a dedicated line overflow call occurs. It is possible to increase the number of dedicated lines, reduce the number of normal dedicated lines, and back up when the dedicated line fails.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a virtualized leased line system in an ISDN network of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of the embodiment. In FIG. 1, an A exchange station time division switch 2 accommodates a terminal 1 and is connected to a B exchange station time division switch 15 by a dedicated line through a leased line trunk circuit 3 and a leased line trunk circuit 9.

The A-switching station time division switch 2 and the B-switching station time division switch 15 are connected to the ISDN network 17 by the primary group interface circuit 4 and the primary group interface circuit 10 in order to use the virtualized leased line.
It is connected to the DN network 17 through a CCITT-compliant 23B + D primary group interface. The primary group interface circuit 4 and the primary group interface circuit 10 are connected to the D channel control circuit 5 and the D channel control circuit 11 for controlling the D channel of the primary group interface, and the D channel control circuit 5 and the D channel control are connected. The circuit 11 executes an incoming / outgoing call protocol process under the control of the central controller 8 and the central controller 14.

The A-switching station time division switch 2 and the B-switching station time division switch 15 accommodate a voice compression trunk 6 and a voice compression trunk 12 for demultiplexing 4 channels of 64 kbps PCM signal into 1 channel of 64 kbps. One of the four demultiplexed channels is controlled by the common line signal control circuit 7 and the common line signal control circuit 13, which are used as signal paths for controlling the other three channels which are speech channels.

The main memory device 18 and the main memory device 19 are memories for holding station information necessary for the exchange process. In this embodiment, the partner station number for establishing the virtual private line in the main memory device 18 is It is registered. In the main storage device 19, data for making a call to the voice compression trunk 12 as a dial-in call when a call for establishing a virtual private line is registered.

FIG. 2 shows the channel structure of the primary group interface. In FIG. 2, the primary group interface has 24 channels from 1 channel (hereinafter, referred to as CH as necessary) to 24CH, and 24CH.
Becomes the D channel (20) of the primary group interface.

The channels of the virtual private line are from 1CH to 2
Any channel in 3CH can be used. In this embodiment, 21CH is used as a virtual private line. 21
In CH, 16 kbps MPC signals are multiplexed in four channels, and common channel signal control channel CCH (22) and speech channels B1 (23), B2 (24),
It is composed of B3 (25).

Next, the operation of this configuration will be described.
In FIG. 1 and FIG. 2, when the terminal 1 transmits to the terminal 16 and the leased line trunk circuit 3 is busy, the central control unit 8 selects an empty channel of the voice compression trunk 6 as a bypass route. The voice compression trunk 6 notifies the central controller 8 of a call-out event and requests the establishment of a virtualized private line if the virtual private line is not established when the channel is selected by the central controller 8. Give out.

When the call control event is received from the voice compression trunk 6, the central control unit 8 reads out the number of the opposite station of the virtual private line registered in the main storage unit 18 in advance, and I
A call is made to the SDN network 17. On the other hand, when the incoming call is received by the voice compression trunk 12 by the dial-in call, the central control unit 14 controls the voice compression trunk 1
2 is executed, and the voice compression trunk 12 automatically responds to the primary group interface circuit 10
Connects the speech path switch of the voice compression trunk 12 to respond to the ISDN network 17.

Upon receiving this response from the ISDN network 17, the central control unit 8 establishes a dedicated virtual line through the ISDN network 17 by connecting the speech path switch of the voice compression trunk 6 from the primary group interface circuit 4. To do. Once this virtual private line is established, B1 (2
3), B2 (24), and B3 (25) are available as dedicated lines, and until the virtualized dedicated line is established, transmission is held by queuing processing as a general service of the exchange. It is also possible to leave it.

In the voice compression trunk 6 and the voice compression trunk 12, B1 (23), B2 (24), B3
When the usage status of the three channels of (25) is monitored and if it is not used for a certain period of time, the central controller 8 or the central controller 14 is notified of the recovery event and a request for canceling the virtualization leased line is issued. And release the set dedicated virtualization line. In this case, when a failure occurs in the original dedicated line (not shown), the virtualized dedicated line through the ISDN network 17 can be used and its backup can be performed.

[0017]

As described above, in the virtualized leased line system of the ISDN network of the present invention, the virtualized leased line is set through the ISDN network only when the traffic is high and an overflow call of the leased line occurs. As a result, the number of leased lines can be increased as needed, the number of ordinary leased lines can be reduced, and backup can be performed when the leased line fails.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration in an embodiment of a virtualized leased line system in an ISDN network of the present invention.

FIG. 2 is a diagram showing a channel configuration of a primary group interface in an example.

[Explanation of symbols]

 1,16 Terminal 2 A Switch Time Division Switch 3,9 Leased Line Trunk Circuit 4,10 Primary Group Interface Circuit 5,11 D Channel Control Circuit 6,12 Voice Compression Trunk 7,13 Common Line Signal Control Circuit 8,14 Central Control unit 15 B exchange time division switch 17 ISDN network 18, 19 Main storage device

Claims (2)

[Claims] 1. When a virtual private line is set up in a private exchange having an I interface, a virtual private line is set up through an ISDN network when a line overflow call occurs, and the virtual private line is established,
One channel among the multiple channels multiplexed is used as a signal path,
A virtualized leased line system in an ISDN network that uses another channel as a communication path, and 64 kbps exchanged through an exchange time division switch
16 kbps MPC signal or 32 kbps PCM signal
In order to connect to the voice compression / separation / demodulation means for compressing into an ADPCM signal and outputting as a multiplexed 64 kbps signal, or separating and demodulating the multiplexed signal to output a 64 kbps PCM signal, the exchange time division switch 64 kbp
When the input / output channel of the sPCM signal is selected, I
Voice compression / separation / demodulation means in the opposite exchange through the SDN network, automatic calling means for automatically calling to set a virtualized leased line for communicating multiplexed signals, and establishment of a virtualized leased line from the ISDN network For incoming calls for
A virtual private line connecting means for automatically connecting the voice compression / separation / demodulation means and the voice compression / separation / demodulation means between the opposite exchanges to the ISDN network connected through the exchange time division switch through a virtual private line A virtualized leased line system in an ISDN network characterized by comprising. 2. The use status of the multiplexed channels is monitored during the establishment of the virtual leased line, and the virtualized leased line is released when a state where there is no channel used other than the signal path continues for a certain period of time. The virtual private line releasing means is provided.
A virtualized leased line system in the described ISDN network.