The serving area interface or service area interface (SAI) is an outdoor

enclosure Enclosure or Inclosure is a term, used in English landownership, that refers to the appropriation of "waste" or " common land" enclosing it and by doing so depriving commoners of their rights of access and privilege. Agreements to enclose land ...

or metal box that allows access to telecommunications wiring.

Alternate names

*Access point (AP) *Cabinet (cab) *B-box (breakout box) *Cross box *Cross-connect box *Jumper wire interface (JWI) *Outside plant interface (OPI) *Pedestal (ped) *Primary cross-connection point (PCP) (UK)"Multimedia Telecommunications" (BT Telecommunications Series), B. Whyte (Ed.), Springer 1997 *Secondary cross-connection point (SCP) (UK) *Telecom cabinet

Function

The SAI provides the termination of individual twisted pairs of a telephony

local loop In telephony, the local loop (also referred to as the local tail, subscriber line, or in the aggregate as the last mile) is the physical link or circuit that connects from the demarcation point of the customer premises to the edge of the commo ...

for onward connection back to the nearest telephone exchange (US: " central office" (CO)) or remote switch, or first to transmission equipment such as a subscriber loop carrier multiplexer and then to the exchange

main distribution frame In telephony, a main distribution frame (MDF or main frame) is a signal distribution frame for connecting equipment (inside plant) to cables and pair gain, subscriber carrier equipment (outside plant). Overview The MDF is a termination point wi ...

(MDF). In the United Kingdom, the components from the PCP onwards to the customer are known as " D-side" (distribution side), and from the PCP back to the MDF as the "E-side" (exchange side). In the United States, the connection back to the MDF is known as the F2 (secondary distribution cable) and/or the F1 (main feeder cable) pairs. SAIs are used in suburban and low-density urban areas, serving some of the same purposes that

manhole A manhole (utility hole, maintenance hole, or sewer hole) is an opening to a confined space such as a shaft, utility vault, or large vessel. Manholes are often used as an access point for an underground public utility, allowing inspection, m ...

s do in high-density urban areas. Besides a cross connect point, they sometimes contain a DSLAM or more rarely a

remote concentrator In modern telephony a remote concentrator, remote concentrator unit (RCU), or remote line concentrator (RLC) is a concentrator at the lowest level in the telephone switch hierarchy. Subscribers' analogue telephone/PSTN lines are terminated on co ...

or both.

References

Local loop Street furniture {{telecommunications-stub

Alternate names

Function

See also

References