Fiber to the x (FTTX) or Fiber in the loop is a generic term for any broadband network architecture using optical
fiber to provide all or part of the local loop used for last mile telecommunications.
As fiber optic cables are able to carry much more data than copper cables, especially over long distances,
copper telephone networks built in the 20th century are being replaced by fiber.

FTTX is a generalization for several configurations of fibre deployment, arranged
into two groups: FTTP/FTTH/FTTB (Fiber laid all the way to the premises/home/building) and FTTC/N
(fiber laid to the cabinet/node, with copper wires completing the connection).

Residential areas already served by balanced pair distribution plant call for a trade-off between
cost and capacity. The closer the fiber head, the higher the cost of construction and the higher
the channel capacity. In places not served by metallic facilities, little cost is saved
by not running fiber to the home.

Fibre to the x is the key method used to drive Next-generation access (NGA), which describes
a significant upgrade to the Broadband available by making a step change in speed
and quality of the service. This is typically thought of as asymmetrical with a download speed of 24 Mbit/s
plus and a fast upload speed. The Definition of UK Superfast Next Generation Broadband OFCOM have
defined NGA as in "Ofcom's March 2010 'Review of the wholesale local access market" "Super-fast broadband
is generally taken to mean broadband products that provide a maximum download speed that is greater than 24 Mbit/s.
This threshold is commonly considered to be the maximum speed that can be supported on current generation (copper-based) networks."

A similar network called a Hybrid fibre-coaxial (HFC) network is used by Cable Television operators but is usually not synonymous with "fiber In the loop",
although similar advanced services are provided by the HFC networks. Fixed wireless and mobile wireless technologies such as Wi-Fi,
WiMAX and 3GPP Long Term Evolution (LTE) are an alternative for providing Internet access.