JPH0420060A - Channel reservation system - Google Patents

Abstract

PURPOSE:To save the trouble of repetition of dialing for many number of times resulting in acquiring an idle speech channel by using a control channel packet to reserve a channel even during talking and using the speech channel with priority when an idle speech channel is made available. CONSTITUTION:An ISDN exchange 1 consists of a channel switch 2, a call controller 3, an ISDN subscriber circuit 4, and a control channel control circuit 5 and connects to ISDN terminal equipments 7a-7c via the ISDN subscriber circuit 4 and the channel switch 2. Then the exchange 1 monitors the state of a speech channel by using a speech channel reservation packet sent from a terminal equipment through the control channel and calls a terminal equipment sending the speech channel reservation packet when the speech channel is idle to allow the terminal equipment to use the idle speech channel with priority. Thus, the idle speech channel is acquired without redialing at a proper waiting time when a idle speech channel is not available on the line.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a channel reservation system in a communication format in which a plurality of terminals are connected to a single digital subscriber line having a speech channel and a control channel. .

[Conventional technology]

L5DN is a communication form that connects multiple terminals to a single digital subscriber line that has a speech channel and a control channel.
5DN Illustrated Reader”. Figure 3 is an example. In the figure, (1) is an l5DN switch, (2
) is a communication path switch, (3) is a call control device, and (4) is l.
5DN subscriber circuit, (5) is a control channel control circuit, (
7a), (7b), and (7c) are l5DN terminals.

Next, the operation will be explained according to the communication procedure sequence shown in FIG. When the l5DN terminals (7a) and (7b) are talking through the l5DN subscriber circuit (4) and the call path switch (2), when the rsDN terminal (7c) performs a call operation to make a call, the l5DN A call control device (3) detects a call setting signal from a terminal (7c) via a control channel control circuit (5). However, the call control device (3) determines that it is not possible to capture the communication channel of the I5DN terminal (7C) because the I5DNi terminals (7a) and (7b) are already talking, and the call control device (3) determines that it is not possible to capture the communication channel of the I5DN terminal (7C). Send a release signal with a reason. The I5DN terminal (7c) recognizes from the release signal that it cannot make a call.

Next, after either the l5DN terminal (7a) or (7b) finishes the call, when the l5DN terminal (7C) makes a call again, the call setting signal of the l5DN terminal (7C) is transferred to the control channel control circuit (5). Detected by the call control device (3) via. The call control device (3) calls the other party's terminal and sends a call acceptance signal to the IS[IN terminal (7C). When the call control device (3) detects that the other party's terminal has responded, the call control device (3) sends a response signal to the I5DNi terminal (7c), thereby allowing the I5DN terminal (7C) to enter a talking state.

(Problems to be Solved by the Invention) Since the calling operation of the conventional 15DNi terminal is performed as described above, when there is no empty call channel on the line,
There is a problem in that the calling operation must be performed again at an appropriate time, and that there is not always an empty channel available at that time, forcing the calling operation to be performed many times.

This invention was made in order to solve the above-mentioned problems, and it is possible to capture an empty channel without having to make a call again at an appropriate time when there is no empty channel on the line. The purpose is to obtain a channel reservation method that can.

[Means to solve the problem]

The channel reservation method according to the present invention provides a communication channel and a
#I In a communication mode in which a plurality of terminal devices are connected to a single digital subscriber line having a control channel, the terminal device has a function of transmitting a communication channel usage reservation packet through the control channel, and the exchange exchanges the reservation packet. The terminal device is called when the communication channel is detected to be empty after receiving the message.

[Effect]

In the channel reservation method according to the present invention, the switching equipment monitors the state of the communication channel by the communication channel reservation packet transmitted from the terminal device through the control channel, and when the communication channel becomes empty, the terminal that transmitted the communication channel reservation packet Call the device and have it preferentially use an empty channel.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (1) is an 15DN exchange, (2) is a communication path switch, (3) is a call control device, (4) is an 15DN subscriber circuit, (5) is a control channel control circuit, and (6) is this control The packet transmitting/receiving circuits (7a), (7b), and (7c) built into the channel control circuit (5) are l
5 (IN terminal, (8a), (8b), (8c)
are these l5DN terminals (7a), (7bl(7C
) is a built-in packet transmitting and receiving circuit.

Next, the operation of this embodiment will be explained according to the communication procedure sequence shown in FIG. l5DNi terminal (7a).

(7b) is in the middle of a call via the l5DN subscriber circuit (4) and the call path switch (2), the l5DN terminal (
7c) performs a calling operation to make a call, l5DNi
The control channel control circuit (5) controls the call setting signal of the terminal (7c)
Detected by the call control device (3) via. Call control device (3
) judges that it cannot capture the communication channel of the l5DN terminal (7c) because the l5DN terminals (7a) and (7b) are already talking, and the l5DN terminal (7c)
send a release signal to the channel with the reason for no channel. Due to the release signal, the 151) Ni end (7c) knows that it cannot make a call, and the packet transmitting/receiving circuit (8
When a communication channel becomes vacant due to c), a channel reservation packet is transmitted on the control channel so that the channel can be used preferentially. The packet transmitting/receiving circuit (
6) receives this channel reservation packet and notifies the contents of the packet to the call control device (3). Call control device (3)
recognizes from the contents of the packet that the I5DN terminal (7c) has reserved the channel, and monitors the status of the communication channel currently in use.

The call control device (3) indicates that either one of the l5DN terminals (7a) and (7b) has ended the call and released the channel.
is detected, the call control device (3) uses the packet transmission/reception circuit (6) built in the control channel control circuit (5) to send a channel reservation notification packet to the l5DN@terminal (7c), thereby 7c). l
The 5DN terminal (7c) responds to this call, and thereafter communicates with the other party's terminal according to the conventional connection success procedure.

In the above embodiment, the l5DN terminal (7c) is called from the l5DN exchange (1), but the sound may be different from the normal call, or an LED may be provided on the l5DN terminal and this LED may be turned on.

〔Effect of the invention〕

As described above, according to the present invention, even if a call is in progress, a channel can be reserved using a control channel packet, and when an empty call channel becomes available, that call channel can be used preferentially. The effect is that the effort of repeating the operation many times and capturing an empty communication channel can be saved.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a communication system that implements a channel reservation method according to an embodiment of the present invention, Fig. 2 is a sequence diagram showing communication procedures in this communication system, and Fig. 3 is a block diagram of a communication system according to a conventional method. , FIG. 4 is a sequence diagram showing a communication procedure in a communication system according to this conventional method. In the figure, (1) is an 15DN exchange, (2) is a communication path switch, (3) is a call control device, (4) is an 15DN subscriber circuit, (5) is a control channel control circuit, and (6) is a control channel. A packet transmitting/receiving circuit built in the control circuit (5), (
7a), (7b), (7c) are l5DN terminals,
(8a), (8b), and (8c) indicate packet transmitting/receiving circuits built into the I5DN terminals (7a), (7b), and (7c). In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] In a communication mode in which a plurality of terminal devices are connected to a single digital subscriber line having a speech channel and a control channel, the terminal device has a function of transmitting a speech channel use reservation packet through the control channel, and the exchange A channel reservation method characterized in that the terminal device is called when an empty communication channel is detected after receiving a packet.