Network interface device

In telecommunications, a Network Interface Device (NID) is a device that serves as the demarcation point between the carrier's edge device and the customer's premises wiring.

Other names

 * Network Interface Unit (NIU)
 * Telephone Network Interface (TNI)
 * System Network Interface (SNI)
 * Telephone network box
 * Optical Network Terminal (ONT) - a type of NID used with fiber-to-the-premises applications.
 * Smartjack - is a type of NID with capabilities beyond simple electrical connection, such as diagnostics.

As demarcation point
In its role as the demarcation point, the NID separates the telephone company's equipment from the customer's wiring and equipment. The telephone company owns the NID itself, and all wiring up to it. Anything past the NID is the customer's responsibility.

Links

 * http://sundance-communications.com/forum/ubbthreads.php/topics/261982/1/New_T1_installation_question