Local Loop Facility Tour


This is a cross-connect box.  It is used to cross-connect feeder cables to local distribution cables serving the immediate area.  The box's physical dimensions are 17 inches wide, 5 feet long and 4 feet high.  Doors on both sides of the cabinet swing open to provide the technicians access.  The box is engineered to economically connect the pairs serving the immediate area to the feeder cables coming from the central office or in some cases from a CEV or remote terminal.

Depending on the nature of the area being served, local distribution pairs will exceed feeder pairs by some predetermined ratio.  For instance, if the ratio is 1.5:1, then there would be three local distribution pairs for each two feeder pairs.  When installing cable within a given community, it is not possible to predict, on a lot-by-lot basis, which customers will be ordering two or more lines.  However, based on demographics of a given area, the phone company can estimate the total demand for service.  As customers order service the phone company can cross-connect a feeder cable pair coming from the central office to an appropriate local distribution pair serving the end user customer.  This system also allows them to more rapidly restore service by switching a customer service from a defective pair to one that is in working condition.  Each cross-connect box is designed for a particular type of connector and for the cable feeder to local distribution cable ratio most appropriate for that area.