JP2919165B2 - Virtualized leased line method in ISDN network - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a virtual private line system for use in a private branch exchange having an I interface, and more particularly, to a virtual private line system in an ISDN network for setting up a virtual private line using an 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 as not to be blocked even at the most busy time in consideration of traffic between the private exchanges facing each other.

[0003]

The operation status of the above-mentioned private switchboard using a dedicated line is several hours per day even in the busiest hours, and there are many non-operating stations without traffic at midnight. Some stations concentrate traffic on a particular day of the week. In this case, although it differs depending on the state of each station, it is not possible to use the leased line only as much as necessary during the busiest time. For this reason, there is a problem that the number of dedicated lines when configuring a network must be used by contracting a large number of lines in consideration of the busiest times.

[0004] The present invention solves such a problem in the prior art, and sets up a virtual private line through the ISDN network only when high traffic and a call overflow of the private line occur. It is an object of the present invention to provide a virtual leased line system in an ISDN network that can increase the number of dedicated lines, reduce the number of ordinary dedicated lines, and back up when a dedicated line fails.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is provided in a private exchange having an I interface, and is provided through an ISDN network when a line overflow call occurs.
When a virtualization leased line is set, and the virtualization leased line is established , one channel of the established virtualization leased line is transmitted to a plurality of low-speed channels.
Demultiplexed into channels, one of which is a signal path,
A virtualized leased line system in an ISDN network using another channel as a communication path, wherein a 64 kbps PCM signal exchanged through a switch time division switch is converted to a 16 kbps signal.
High efficiency coding method such as sMPC or 32kADPC
And compress the compressed signals of multiple channels into one
Multiplexed as 64kbps signal and output to time division switch
Or multiplexed input through a time division switch.
A 64 kbps signal is separated and demodulated to obtain a plurality of 64 kbps signals.
Audio compression separation demodulation signal output as bpsPCM signal
And 64 kbps to connect to the time division switch
When the input / output channel of the PCM signal is selected, IS
Voice compression separation / demodulation means phase in the opposite exchange through the DN network
Automatic calling means for automatically calling to set up a virtualized dedicated line for performing multiplexed signal communication between each other, and voice compression / separation / demodulation means and a switch when receiving an incoming call from the ISDN network for establishing a virtualized dedicated line ISDN connected through time-division switch
A virtual private line connecting means for connecting the voice compression separating / demodulating means between the opposite exchanges with a virtual private line by automatically responding to the network. Also preferably, voice
64 kbps compressed and multiplexed by the compression separation / demodulation means.
Some signals contain information on multiple traffic channels and one signal path.
Multiplexed during the establishment of the virtualized leased line.
Monitors channel usage and is used for other than signal paths
In this configuration, a dedicated virtual line release unit is provided for releasing a dedicated virtual line when a state without a communication channel continues for a certain period of time.

[0006]

The virtual private line system in the ISDN network according to the present invention having such a configuration is necessary because the virtual private line is set through the ISDN network only when the traffic is high and the overflow of the private line occurs. , The number of dedicated lines can be increased, the number of ordinary dedicated lines can be reduced, and backup can be performed in the event of a dedicated line failure.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an ISDN network according to an embodiment of the present invention; FIG. 1 shows a configuration in the embodiment. In FIG. 1, the A exchange time division switch 2 accommodates the terminal 1 and is connected to the B exchange time division switch 15 via a leased line trunk circuit 3 and a leased line trunk circuit 9 via a leased line.

The A exchange time division switch 2 and the B exchange 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 dedicated virtual 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 a D channel control circuit 5 and a D channel control circuit 11 for controlling the D channel of the primary group interface. The circuit 11 executes a transmission / reception protocol process under the control of the central controller 8 and the central controller 14.

The A exchange time division switch 2 and the B exchange time division switch 15 accommodate a voice compression trunk 6 and a voice compression trunk 12 for demultiplexing four 64 kbps PCM signals into one 64 kbps channel. One of the four channels to be demultiplexed is controlled by a common line signal control circuit 7 and a common line signal control circuit 13 used as signal paths for controlling the other three channels serving as communication channels.

The main storage device 18 and the main storage device 19 are memories for holding station information necessary for the exchange processing. In the present embodiment, the counterpart station number for establishing the virtualization dedicated line in the main storage device 18 is It is registered. In the main storage device 19, data for making the voice compression trunk 12 receive an incoming call as a dial-in incoming call when receiving an incoming call for establishing a virtual private line is registered.

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

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

Next, the operation of this configuration will be described.
In FIGS. 1 and 2, when a call is transmitted from the terminal 1 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 control device 8 of a call event if the virtualization exclusive line is not established when the channel is selected by the central control device 8, and issues a request for establishing the virtualization exclusive line. Put out.

When receiving a calling event from the voice compression trunk 6, the central control unit 8 reads out the number of the opposite station of the virtualization dedicated line registered in the main storage unit 18 in advance.
A call is made to the SDN network 17. On the other hand, at the receiving station, in the case of an incoming call to the voice compression trunk 12 due to dial-in reception, the central control unit 14
2 and the voice compression trunk 12 automatically responds to the primary group interface circuit 10.
From the voice compression trunk 12 to make a response to the ISDN 17.

The central control unit 8 having received this response from the ISDN network 17 connects the speech path switch of the voice compression trunk 6 from the primary group interface circuit 4 to establish a virtual private line through the ISDN network 17. I do. Once this virtualization dedicated line is established, B1 (2
3), B2 (24) and B3 (25) are available as dedicated lines, and until the virtualized dedicated line is established, the queuing process is performed as a general service of the exchange, and the call is transmitted. It is also possible to leave it.

In the voice compression trunk 6 and the voice compression trunk 12, B1 (23), B2 (24), B3
(25) The use status of the three channels is monitored, and if the channel is not used for a certain period of time, a recovery event is notified to the central control device 8 or the central control device 14 and a release request for the virtualization dedicated line is issued. To release the set virtualization dedicated line. In this case, when a failure occurs on the original dedicated line (not shown), the virtualized dedicated line via the ISDN network 17 can be used and its backup can be performed.

[0017]

As described above, in the virtual private line system in the ISDN network according to the present invention, the virtual private line is set through the ISDN network only when the traffic is high and the overflow of the private line occurs. This has the effect that the number of dedicated lines can be increased as necessary, the number of ordinary dedicated lines can be reduced, and backup can be performed in the event of a dedicated line failure.

[Brief description of the drawings]

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

FIG. 2 is a diagram illustrating a channel configuration of a primary group interface in the embodiment.

[Explanation of symbols]

 1,16 terminal 2A exchange time division switch 3,9 Dedicated 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 office time division switch 17 ISDN network 18, 19 Main storage device

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-237257 (JP, A) JP-A-3-96054 (JP, A) JP-A-3-106234 (JP, A) JP-A-3-237 125551 (JP, A) JP-A-4-15859 (JP, A) JP-A-4-158660 (JP, A) JP-A-5-199315 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H04M 3/00 H04M 3/16-3/20 H04M 3/38-3/40 H04M 7/00-7/16 H04Q 3/58-3/62

Claims (2)

(57) [Claims] Claims: 1. A private exchange having an I interface, which is provided through an ISDN network when an overflow call occurs.
When a virtualization leased line is set, and the virtualization leased line is established , one channel of the established virtualization leased line is transmitted to a plurality of low-speed channels.
Demultiplexed into channels, one of which is a signal path,
A virtualized leased line method in an ISDN network using another channel as a communication path, and 64 kbps exchanged through an exchange time division switch.
PCM signal is 16 kbps MPC or 32 kADPC
Compressed by a high-efficiency coding method such as
Channel signals are multiplexed as one 64 kbps signal.
Output to the time division switch or through the time division switch.
Multiplexed 64 kbps signal
Separate, demodulate and output as multiple 64kbps PCM signals
And a 64 kbps PC for connection to the time division switch.
When the input / output channel of the M signal is selected, the ISDN
Between voice compression separation and demodulation means in the opposite switch through the network
An automatic calling means for automatically calling to set up a virtualization dedicated line for performing multiplexed signal communication, and an incoming call for establishing a virtualization dedicated line from the ISDN network,
Virtualization dedicated line connection means for automatically responding to the ISDN network connected through the voice compression separation / demodulation means and the exchange time-division switch and connecting the voice compression separation / demodulation means between the opposite exchanges with a virtualization dedicated line; A virtual private line system in an ISDN network, comprising: 2. An audio compression separation / demodulation means for compression multiplexing.
Some 64 kbps signals include multiple communication channels
And information of one signal path are multiplexed to establish a virtual dedicated line
Monitors the usage status of channels multiplexed in the
2. The virtual private line system in an ISDN network according to claim 1, further comprising virtual private line release means for releasing a virtual private line when a state in which there is no communication channel used outside continues for a predetermined time.