JP2970215B2 - Line controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line controller provided with a control unit for using a control channel of an ISDN line as an information channel.

[0002]

2. Description of the Related Art Recently, one subscriber line has two data channels (B channels) and one signal channel (D channel).
Channel) and ISDN (Integr
atedServices Digital Network) services have become widespread and have been used for telephone, computer communications, G4 facsimile communications, and the like.

[0003] However, in the conventional ISDN line, two B channels are used in common, and at least one of them uses a communication that can use packet exchange of the D channel, and a new call is received. Sometimes, even though the D channel is vacant, there is no line control device that shifts the communication that can use the packet exchange of the above D channel to the D channel and transfers the B channel to a new incoming communication. I
The advantages of the SDN line could not be used well.

[0004]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and has been proposed when a new incoming call is received in a state where two B-channels are used for common communication on an ISDN line. It is an object of the present invention to provide a line control device having a control unit for transferring one of the above two communications to the D channel and transferring the B channel to new communications.

[0005]

According to a first aspect of the present invention, there is provided a line control apparatus according to the first aspect of the present invention, wherein two B channels have no free space in an ISDN line. When at least one channel receives packet-switched communication via the D channel and receives a new call through the D channel,
A control unit that suspends communication that can use packet switching of the D channel, switches from the B channel to the D channel, and resumes communication, while using a vacant B channel for newly received communication. It has a configuration with. Further, according to the line control device of the present invention, the communication capable of performing packet switching by the D channel
After switching to the channel and handing over the B channel to the newly called communication, if it is determined that one of the two B channels that have been in use has become free, the communication switched to the D channel is performed. , And a control unit for switching to an empty B channel again.

[0006]

According to the circuit control device of the present invention, in the ISDN line, there is no vacancy used for two B-channel co-communications, and at least one of the channels uses the D-channel packet exchange other than the telephone. When there is a new incoming call while communication that can be used is in use,
Since the communication that can use the D-channel packet switching is switched to the D-channel packet switching, the B-channel is used for the newly received communication.
All three channels of the SDN line can be used effectively.

[0007]

An embodiment of the present invention will be described below. FIG. 1 is a diagram showing an example of an ISDN network for explaining a network controller according to the present invention. The line controller according to the present invention will be described with reference to FIG.

At the time of calling, each terminal receives a priority according to the importance of the communication. The input priority is stored at the calling side and is sent to the called side in a protocol SETUP (call setup request) message and stored. In the ISDN line 10 at the point d, the two B channels B1 and B2 are respectively a facsimile FAX1 and a telephone TE.
When a new call is received from the facsimile FAX 4 at the point c in a state where there is no vacancy used in the L1 (FIG. 1)
(A)), the priority of the facsimile communication of the facsimile FAX1 communicable using this communication and the packet exchange of the D channel is compared. As a result, if the communication from the facsimile FAX 4 at the point c has a higher priority,
The facsimile communication of the facsimile FAX1 communicable using the packet exchange of the channel is switched to the packet exchange of the D channel, and the facsimile FA at the above-mentioned point c is switched.
Use B channel for communication from X4 (Fig. 1
(B)).

The above operation will be described in more detail. In the ISDN line 10 at the point d, two B channels B
1 and B2 are used for facsimile FAX1 and telephone TEL1, respectively, and there is no space.
When the priority is set from AX4 and there is an incoming call at point d via the D channel (FIG. 1 (A)), each terminal at point d sends a SETUP (call setup request) 1 message of this protocol. Facsimile FAX not reading or communicating
2 returns an ALERT (Alerting: notification of calling from the called terminal) 1 message to the facsimile FAX 4 at the point c via the D channel. However, since the B channel is not vacant, the B channel is not connected and no incoming call can be made. In such a state, the facsimile F that can communicate using the packet exchange of the D channel at the d point is used.
AX1 has its own communication priority and the above SETUP1.
Comparing with the priority included in the message, if the own priority is higher, the communication is continued as it is. If its own priority is low, the communication is interrupted and DISC (Discon
nect: call release request) message via the D channel
The fax is sent to the facsimile FAX 3 at the point b, thereby disconnecting the B channel and releasing the call number on the facsimile FAX 3 side, and returning a REL (Release: channel disconnection completion notification and call number release request) message. When the facsimile FAX1 receives the REL message, the facsimile FAX1 also releases the call number of the facsimile FAX1 and the RELCOM.
(Release Complete: notification of completion of channel release and call number release completion) is sent to the facsimile FAX 3, and the call on the B channel is completed.

Next, the facsimile FAX 1 sends a D-channel packet exchange SETUP (call setting request) 2 message to the facsimile FAX 3 via the D channel. Facsimile FAX3 receives this, and first CA
When an LL PROC (Call Proceeding: notification of call setup processing) message is returned and the call is started, ALERT is started.
(Alerting: notification of calling from the called terminal) 2 Sends a message to the facsimile FAX1. Facsimile FAX3
Sends a CONN (Connect: response notification of the called terminal) message to the facsimile FAX 1 when the above-mentioned call is answered, the D-channel packet switching channel is connected,
The above-mentioned interrupted communication is shifted to packet switching and restarted.

On the other hand, a call (FAX3
Upon completion of (FAX1), the facsimile F2 at the point d responds to the call from the facsimile FAX4 at the point c and sends a CONN message to the facsimile FAX4.
And the vacant B1 channel is connected, and communication (FAX4 → FAX2) using the new B1 channel starts (FIG. 1B).

When the data transmission (FAX4 → FAX2) using the new B1 channel is completed, a DISC (Disconnect: call release request) message is sent from the facsimile FAX4 to the facsimile FAX2 via the D channel. Is disconnected and the call number of the facsimile FAX 2 is released, and the REL (Release
: Channel disconnection completion notification and call number release request) message is returned. When the facsimile FAX4 receives the REL message, it also releases the call number of the facsimile FAX4, sends a REL COM (Release Complete: notification of channel release and call number release completion) message to the facsimile FAX2, and completes the call (FAX4 → FAX2). I do. 20 to 30 in FIG. 2 show such a facsimile FA.
FIG. 7 is a flowchart showing a series of operations from the priority setting of X4 to the end of communication.

When the communication (FAX3 → FAX1) resumed after the packet exchange is completed, the data transmission (FAX4 → FAX) through the new B1 channel is completed.
If 2) continues, the DI between the facsimile FAX 3 and the facsimile FAX 1 is performed in the same manner as in the above-described call completion procedure.
SC message, REL message and REL COM
The message is transmitted and received, and the call (FAX3 → FAX1) is completed.

Conversely, while the communication (FAX3 → FAX1) resumed after the packet exchange has been continued, the call using the new B1 channel (FAX4 → FAX2) is completed, or the call on the B2 channel is terminated. When the B channel is vacant due to completion or the like, the communication of the packet exchange (FAX3 → FAX1) is interrupted and the facsimile FAX is performed in the same manner as described above (however, transmission and reception are reversed).
3 and the facsimile FAX 1 transmit and receive the DISC message, the REL message, and the REL COM message, and once complete the call (FAX 3 → FAX 1). Then, the facsimile FAX1 sends the B channel S
An ETUP (call setup request) 3 message is sent to the facsimile FAX 3 via the D channel. Facsimile FAX
In response to this, CALL PROC (Call P
roceeding: When a call is returned and a call is started, an ALERT (Alerting: notification of a call from a called terminal) 3 message is sent by facsimile facsimile.
Send to 1. Next, when the facsimile FAX 3 responds to the above call, it sends a CONN (Connect: response notification of the called terminal) message to the facsimile FAX 1, the vacant B channel is connected, and the interrupted communication (FAX 3 → FAX 1) ) Is resumed by returning to the B channel. 3 to 64 in FIG. 3 show such a facsimile FA.
It is the flowchart which showed a series of operation | movement of X1.

[0015]

[0016]

According to the circuit controller of the present invention, the ISD
On N lines (B channel x 2 + D channel x 1)
There is no free space used for the two B-channel co-communications, and at least one of the channels is newly used while communication capable of using the packet exchange of the D-channel other than the telephone is used. When a call is made, the communication which can use the packet exchange of the D channel is performed by the D
Since the B channel is used for the newly received communication by switching to the packet exchange of the channel, all the three channels of the ISDN line can be effectively used, and the transmission of data per unit time can be performed. Increases efficiency.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams showing an example of an ISDN network for explaining a network controller according to the present invention.

FIG. 2 is a flowchart showing a series of operations from the priority setting of the facsimile FAX 4 to the end of communication.

FIG. 3 is a flowchart showing a series of operations of the facsimile FAX1.

[Explanation of symbols]

 10 ISDN line B1, B2 B channel D D channel

Claims (2)

(57) [Claims] In an ISDN line, two B channels have no vacancy, and at least one of them has a D channel.
When a new call is received while communication that can use the packet exchange of the channel is used, the communication that can use the packet exchange of the D channel is interrupted, the B channel is opened, and the packet exchange of the D channel is performed. A line control device comprising a control unit characterized in that the communication is resumed by switching to B, and the vacant B channel is used for the called communication. 2. The communication system according to claim 1, wherein the control unit performs communication from the B channel to the D channel by using the newly received communication.
A line control device characterized in that, after switching to a channel, when it is determined that one of the two B channels is vacant, the communication switched to the D channel is switched to a vacant B channel. .