摘要 |
PURPOSE:To extend the conference earth number, by providing the conference trunks storing a terminal at the outgoing side and two terminals at the incoming side respectively of the exchange network. CONSTITUTION:The subscriber A dials the number of the subscriber B. The outgoing trunk OGT is caught, and the information is supplied to the control device of the exchange storing the subscriber B via the incoming trunk ICT. When the conference telephone connection information 34 is detected, the conference trunk CFT is caught to secure a connection to the trunk ICT. In such a way, the subscriber A is connected to the subscriber B. Then subscriber B performs a hooking to increase the members of the conference, and thus the subscriber terminal stored in an exchange switch is caught. Under these conditions, the subscriber B dials the subscriber C. As a result, the exchange to which the subscriber C belongs is connected to the exchange to which the subscriber B belongs to secure the participation in the conference. |