Patent ID: 6961308

Claim:
An ATM (Asynchronous Transfer Mode) switching system for connecting a plurality of subscriber terminal units with a switching network by the use of an ATM switch operated in ATM, comprising: a call history memory for maintaining call histories of requests for connection from said plurality of subscriber terminal units; a reserved connection memory for writing and reading reserved connection information; and a call-signal processing section to: generate a request for connection with respect to said switching network by the use of said call histories in said call history memory in the case where no call was issued from said plurality of subscriber terminal units during a predetermined period of time, store contents of a response from said switching network with respect to the request for connection in said reserved connection memory as updated reserved connection information, and use said updated reserved connection information which has been stored in said reserved connection memory to control said ATM switch in the case where there was a call from any of said subscriber terminal units when the request for connection is the same as the reserved connection information which has been updated and stored in said reserved connection memory.