PURPOSE: To improve line efficiency.

CONSTITUTION: This system includes a network management device 1, cross- connection devices 2 and 3 which has an on-hit switching function for constituting a path according to an indication from the network management device l, cross-connection devices 4 and 5 which are placed halfway on the path and perform path switching, and network terminating devices 6, 7, 8, and 9 which have a network terminating function and perform connection confirmation processing. When there is no in-use line 20 at the time of the line connection confirmation processing before a line is lent, the line connection confirmation processing is performed by using a stand-by line 19 and the stand-by line 19 is switched to an in-use line 20 without short break immediately after the path of the lent line is made free.