ATM DEVICE

PROBLEM TO BE SOLVED: To perform connection setting for a SVC call even when there is no empty band to satisfy a declaration band by reserving an empty band that sets call connection by changing the connection of a certain line to another line when a declaration band of call setting exceeds the empty band of each line. SOLUTION: This device has a changing means which reserves an empty band to set call connection by changing connection of a certain line to another line when a declaration band of call setting exceeds an empty band of each line. In the ATM device, a call setting part 2 sets the connection of a SVC call to an ATM line in response to a call setting request from a terminal. A connection changing part 3 changes connections when the part 2 fails in connection setting. A regular supervising part 4 periodically supervises the state of a band in use and a setting state of the connection. A control data 5 stores information which efficiently performs call setting processing and connection changing processing.