The Local Loop refers to the physical wiring that connects the central office of the PSTN to the end user. At the customer site, the local loop, also referred to as the “last mile”, terminates at the customer’s demarcation point, which is the point where the LEC or CLEC hands off the responsibility of connecting to the end user.
The end user’s inside wiring (the twisted pair phone line and Cat5 network cabling inside your business or home) is connected to a Network Interface Device (NID), which is installed by and the responsibility of the LEC. The NID is located at the demarcation point and connects customers’ inside wiring to the local loop, which in turn connects to the LEC’s central office. That’s all for now. Next up: the central office.