Exchange and conference communication method therefor

An exchange including a plurality of line interfaces to be connected with a line wire, and one or more extension interfaces to be connected with an extension, for connecting either the line wire and the extension or the extension and another extension, thereby to form a channel, comprising:

• a time-division switch, connecting the line wire and the extension and for forming a channel between each other;
• a conference trunk for synthesizing voices;
• a memory for grouping at least two telephone numbers of the extension number assigned to the extension and the telephone number of the line wire, into at least one group and for registering the group;
• and
• a controller, controlling the exchanging action either between the line wire and the extension or between the extensions,
• wherein when said controller receives a conference opening demand together with a group number communications via a first extension and the group number, said controller:
• performs a conference calling termination by acquiring the number of other extensions belonging to the same group as that of said first extension having demanded the conference communications, from said memory;
• and
• controls said time-division switch so as to establish unidirectional communications from said first extension to the other extensions responding to the conference calling termination, and
• wherein said controller further controls, when it receives a demand for bidirectional communications from any extension for said unidirectional communications, said time-division switch so that said extension having demanded the bidirectional communications and the first extension may make bidirectional communications.

The exchange including a plurality of line interfaces to be connected with a line wire, and one or more extension interfaces to be connected with an extension, for connecting either the line wire and the extension or the extension and another extension, thereby to form a channel, comprising:

• a time-division switch for connecting the line wire and the extension and for forming a channel between each other;
• a conference trunk for synthesizing voices;
• a memory for grouping at least two telephone numbers of the extension number assigned to the extension and the telephone number of the line wire, into at least one group and for registering the group;
• and
• a controller for controlling the exchanging action either between the line wire and the extension or between the extensions,
• wherein when said controller receives a conference opening demand together with a group number via a first extension, said controller:
• performs a conference calling termination by acquiring the number of other extensions belonging to the same group as that of the first extension having demanded the conference communications, from said memory;
• and
• controls said time-division switch so as to establish unidirectional communications from said first extension to the other extensions responding to the conference calling termination,
• wherein said controller controls, when it receives a demand for bidirectional communications from any extension for the unidirectional communications, said time-division switch and said conference trunk so that the extension having demanded said bidirectional communications and said first extension may make bidirectional communications, and
• wherein in said bidirectional communications among three or more said of the first extension and the other extensions, said controller controls, when it selects the extension for a secret from the extensions of the bidirectional communications and receives a secret communication demand via said first extension, said time-division switch for the secret communications so that only the extension selected and said first extension.

A conference communication method for an exchange including a plurality of line interfaces to be connected with a line wire, and one or more extension interfaces to be connected with an extension, for connecting either the line wire and the extension or the extension and the extension, thereby to form a channel, wherein another exchange includes:

• a time-division switch for connecting the line wire and the extension and for forming a channel between each other;
• a conference trunk for synthesizing voices;
• a memory for grouping at least two telephone numbers of the extension number assigned to the extension and the telephone number of the line wire, into at least one group and for registering the group;
• and
• a controller for controlling the exchanging action either between the line wire and the extension or between the extensions,
• wherein the controller comprises:
• a conference opening demanding step of receiving a conference opening demand via a first extension and the group number;
• a conference calling termination step of performing a conference calling termination by acquiring the number of other extensions belonging to the same group as that of said first extension having demanded said conference communications, from the memory;
• and a unidirectional communication step of controlling said time-division switch so as to establish unidirectional communications from said first extension to the other extensions responding to said conference calling termination, and
• wherein said controller further comprises:
• a bidirectional communication demanding step of receiving a demand for bidirectional communications from any extension for said unidirectional communications;
• a bidirectional communication step of controlling the time-division switch and said conference trunk so that the extension having demanded said bidirectional communications and said first extension may make bidirectional communications;
• and an attending step of transmitting the signal synthesized by said conference trunk, as a reception voice to the other extension not participating in the bidirectional communications, so that the other extension not participating in said bidirectional communications can be attended.