Sub-loop unbundling

In the telephony business, sub-loop unbundling (SLU) is a type of unbundled access whereby a sub-section of the local loop is unbundled. To increase market competition and consumer choice, government regulators may "unbundle" services by requiring a company that owns local telephone lines to allow other companies to connect their own equipment to those lines in street cabinets close to the homes of potential customers (sub-loops).

In practice this often means the competitor placing a small street cabinet with a DSLAM, next to a telco local copper aggregation cabinet or serving area interface and using a "tie cable" to connect to the last part of the local loop into customers' homes. The village of Lyddington in the rural county of Rutland was the first example of SLU in the UK when local provider Rutland Telecom unbundled the cabinet to offer VDSL broadband.