PURPOSE: To connect a line with a high-priority network equipment by switching the connection of a low-priority equipment under connection to packet exchange when a party requesting connection is provided with high priority by assigning the priority to the connecting party with the ISDN line contracted equipment.
CONSTITUTION: When a line service change detecting part 101 receives a request to switch line service, an idle line discriminating part 102 discriminates whether there is any idle line or not. When it is discriminated that there is no idle line and the priority of a requested line is higher than the priority of the connected line as a result of a priority discriminating part 104 for discriminating the priority of the connected requested line and the priority of the connected line, the line connection is switched by a connected line switching part 105.
ITO YUJI
KAMEYAMA TAKESHI
