In the United States, the NT1 is generally provided by the customer or integrated into the customer's equipment and the U interface is the termination point of the ISDN network.
The NT1 is generally provided by the customer. This was in the United States. The NT1 is generally integrated into the customer's equipment. This was in the United States. The U interface is the termination point of the ISDN network. This is in the United States.