JPH03155255A - B channel congestion informing system - Google Patents

Abstract

PURPOSE:To inform the presence of a call requesting person by transmitting a user information message to a terminal using a B channel when a call set message is received and there is no unused B channel in a bus to which a transmitting terminal is connected. CONSTITUTION:For example, when terminals 3 and 4 are under communication and an exchange 1 receives the call set message from a terminal 5 while all the B channels of a bus 2 are under using, the vacancy of the B channel is checked and when it is judged that there is no used B channel, a release completion message is transmitted to a call originating terminal. Next, the number of the terminal using the B channel in the call originating terminal connecting bus is calculated. The edited user information message is transmitted to the terminal with this calculated number. On the other hand, when the presence of the unused B channel is detected by checking the vacancy of the B channel, the call set message is accepted and a call connection processing is executed. Thus, it can be informed that the presence of a subscriber which can not set a call.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to user-to-user information notification in an exchange having a CCITT-compliant interface, and particularly relates to a B-channel congestion notification system.

[Prior Art] Conventionally, as a switch capable of transmitting and receiving user information messages, there is, for example, one that has a CCITT-compliant interface and accommodates a plurality of terminals connected to one bus. In this exchange, a call cannot be made if there is no usable channel on the bus to which the terminal is connected.

[Problem to be Solved by the Invention] However, in this conventional switching system, if there is no usable channel (i.e., the call cannot be made, the caller repeatedly tries to make a call, and then the channel is not available). This has disadvantages in that the subscriber who is using the B channel has to wait for the next channel to be acquired and is not informed that there is a call requester.

[Means for Solving the Problems] The technical means of the present invention for solving such problems is that a plurality of terminals are connected via a bus, and a CC
In an exchange having an ITT-compliant interface and capable of transmitting and receiving user information messages, a telephone number detecting means for determining the telephone number of a terminal connected to the bus and using the B channel, and upon receiving a call setting message, If there is no unused B channel on the bus to which the calling terminal is connected,
and message transmitting means for transmitting a user information message to a terminal using the B channel determined by the telephone number detecting means.

[Embodiment] Hereinafter, a B channel congestion notification system according to an embodiment of the present invention will be described based on the accompanying drawings.

FIG. 1 is an explanatory diagram showing the premise of a B channel congestion notification system according to an embodiment of the present invention. In the figure, terminals 3 and 4
．． 5 is connected to the bus 2 and to the exchange 1. The exchange 1 has a CCITT-compliant interface and is capable of transmitting and receiving user information messages to and from the terminal 3°4.5. In this exchange 1, there is a phone number detecting means for detecting the phone number of a terminal connected to the bus 2 and using the B channel, and a phone number detecting means that detects the phone number of a terminal connected to the bus 2 and using the B channel, and a phone number detection means that detects the phone number of the terminal connected to the bus 2 and using the B channel. If there is no B channel, message transmitting means is provided for transmitting a user information message to the terminal using the B channel determined by the telephone number detecting means.

Next, the functions of the exchange 1 according to this embodiment will be explained with reference to the flowchart in FIG. 2. Now, in FIG. 1, it is assumed that terminals 3 and 4 are in communication, all B channels on bus 2 are in use, and exchange 1 receives a call setup message from terminal 5.

At this time, first, a B channel vacancy check is performed (2-
1). As a result, if it is determined that there are no unused B channels, a release completion message is sent to the calling terminal (
2-3). Next, the telephone number of the terminal using the B channel on the calling terminal connection bus is determined (2-4). Then, the user information message for the terminal that is using the B channel is sent to u.
2-5) A user information message is transmitted to the terminal with the telephone number obtained above (2-8).

On the other hand, if the presence of an unused B channel is detected by the B channel empty check (2-1), the call setting message is accepted and call connection processing is performed (2-2).

[Effects of the Invention] As explained above, according to the B channel width notification method of the present invention, when the exchange receives a call setup message, if there is no unused B channel on the bus to which the terminal is connected, Since a user information message is sent to a terminal that is using the B channel, it is possible to notify subscribers who are using the B channel that there is a subscriber who cannot set up a call because all B channels are in use. There is.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the premise of the B channel width notification method according to the embodiment of the present invention, and FIG.
3 is a flowchart showing the procedure of a channel congestion notification method. Switch 2: Bus 3: Terminal 4: Terminal 5: Terminal

Claims (1)

[Claims] When multiple terminals are connected via bus and CCIT
In an exchange having a T-compliant I interface and capable of transmitting and receiving user information messages, a telephone number detecting means for determining the telephone number of a terminal connected to the bus and using a B channel, and upon receiving a call setup message, If there is no unused B channel on the bus to which the calling terminal is connected, message transmitting means is provided for transmitting a user information message to the terminal that is using the B channel determined by the telephone number detecting means. A B channel congestion notification method characterized by: