Asynchronous transfer mode network providing stable connection quality

This invention relates to an asynchronous transfer mode (ATM) network having a network controller which controls quality of connections in the ATM network. In an asynchronous transfer mode network (), a network controller () is connected to terminal equipment units () through logic transmission line circuits () so as to receive a call signal which includes a parameter representative of a network class and which is produced by one of the terminal equipment units. Each of the terminal equipment units is connected to one of ATM exchangers () each of which is connected to at least one of them. The control network controller is connected to the ATM exchangers through logic transmission line circuits () so as to order them to admit a connection required by the call signal.