JP2602250B2 - ISDN terminal transfer destination address notification method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a communication system in which call transfer is performed in ISDN using information between users in a call control message.

[Conventional technology]

Conventionally, call forwarding has been described on pages 44 to 48 of Monthly Business Business Communication magazine published by Planning Center Co., Ltd., March 23, 1986, March 23, Vol. In this way, the called party registers the forwarding address in advance from the terminal to the nearest local transportation machine, and when a call from the calling side to the called side occurs, the call is transferred via the called local exchange. It was a transfer method to the destination.

[Problems to be solved by the invention]

The above-mentioned prior art does not take into consideration that a communication fee is also charged at the receiving side terminal, but a charge for two calls is imposed in one-to-one communication, and further, substantially one call is charged. There was a problem of occupying three terminals.

An object of the present invention is to charge a charge to a called terminal in a call transfer realized only by the function of the terminal.
An object of the present invention is to prevent the called terminal from being occupied during a transfer call.

[Means for solving the problem]

The above-mentioned object is achieved in a case where the called-side terminal in which the user is absent has the user moving destination set in advance by the inter-user information in the call control message which is a response to the calling request message from the calling-side terminal. Set the transfer destination address indicating the address of the terminal installed in the transfer destination address area and send it to the calling terminal, and the calling terminal automatically returns to the transfer destination based on the transfer destination address Achieved by calling.

[Action]

When the called ISDN terminal without the user receives the SETUP message, which is a call request from the calling ISDN terminal, the called user is not present in the inter-user information in the call control message that is the response. The destination address that has been input beforehand is automatically set in the destination address area, and a response message is transmitted to the calling ISDN terminal.

As a result, the calling ISDN terminal sets the transfer destination address in the destination address area 25 as the destination address in the SETUP message, which is a call request for a recall, and transmits the destination user. Is installed where
Direct calls to ISDN terminals are possible.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1, 2, and 3.

First, the user of the calling ISDN terminal 1 designates the called ISDN terminal 6 in an identifiable expression form by using the keyboard 14 and the mouse 15 as input means to start the calling operation by the application program 8. Command to. The application program 8 receiving the notification notifies the call control 11 of the ISDN number indicating the called ISDN terminal 6. Call control 11 uses the IS
The DN number is set in the destination address area 25 of the SETUP message which is a call request, and the D number is set via the data link control LAPD16.
Send a call signal on channel 18.

The SETUP message is sent to the called ISDN via ISDN5.
It is transmitted to terminal 6.

Triggered by receiving this SETUP message, the call control 11 of the user-absent call-in side ISDN terminal 6 causes the call-in side user to input the transfer-destination ISDN terminal 7 which has been input in advance. Is automatically set in the transfer destination address area 28 in the inter-user information in the rejection response message to the SETUP message. Thereafter, the rejection response message is transmitted to the calling ISDN terminal 1 via the data link control LAPD16, and transmitted to the calling ISDN terminal 1 via the ISDN5.

The call control 11 of the calling ISDN terminal 1 is based on the absence of the user
When the rejection response message from the DN terminal 6 is received as a response to the SETUP message, the transfer destination call side IS set in the inter-user information in the rejection response message.
A transfer destination address that can identify the DN terminal 7 for recalling
SETUP Set the destination address area in the message, and
Send UP message as a call request.

The transfer destination called ISDN terminal 7 transmits a CONN message indicating acceptance of the call request, thereby setting a call for one call between the calling user and the transfer destination user. Transfer communication becomes possible only with the function.

As described above, according to the present embodiment, there is an economic effect that no communication fee is charged to the ISDN terminal 6 during the transfer communication.
The terminal 6 is not occupied and can be used for other purposes. This has an effect of improving the device use efficiency, and further has an effect that transfer communication can be realized regardless of the presence or absence of the transfer function of the rope.

〔The invention's effect〕

According to the present invention, in realizing the incoming call transfer function, the communication fee after the transfer is completed is sufficient for one call, so that there is an economical effect. Since the device does not need to be occupied, there is an effect that the device can be used effectively in time.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the configuration of an ISDN to which the present invention is applied;
FIG. 2 is a block diagram showing an embodiment of an ISDN terminal for realizing the present invention, and FIG. 3 is a block diagram showing an example of a call control message format used by the present invention. 1 ... ISDN terminal on the calling side, 2 ... ISDN interface, 3
…… Network termination equipment, 4 …… Subscriber line, 5 …… ISDN, 6 ……
Called ISDN terminal without user, 7: Called destination ISDN terminal, 8: Application program, 9: Display control unit, 10: Input control unit, 11: Call control, 12: Net Work layer control unit, 13 display, 14 keyboard, 15 mouse, 16 LAPD, 17 data link control unit, 18 D channel, 19 B channel, 20
... Line control unit.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tohru Hoshi 1099 Ozenji Temple, Aso-ku, Kawasaki City, Kanagawa Prefecture, Hitachi Systems Development Laboratory Co., Ltd. (56) References JP-A-53-70608 (JP, A) JP-A-62-30498 (JP, A) JP-A-63-86647 (JP, A) JP-A-63-252052 (JP, A) JP-B-49-13087 (JP, B1)

Claims (1)

(57) [Claims] In a digital network terminal integrated with an ISDN service, a call destination side is provided by providing a transfer destination address area in information between users which is one of information elements of a call control message.
This is the first response from the called ISDN terminal to the SETUP (set-up) message, which is a call setup request from the ISDN terminal, and is received by the message calling ISDN terminal whose transfer destination address is set in the inter-user information. An ISDN terminal transfer destination address notification method, based on a transfer destination address, in which when a called user is absent, reconnection to a place where the user exists can be performed only by a terminal function.