Serving area interface
Encyclopedia
The serving area interface or service area interface (SAI) often called B-box, cross-connect box, cross box, ped (for pedestal), or access point (AP) is an outdoor telecommunications cabinet
usually mounted on the ground on cable right-of-way
s, but sometimes also on telephone poles. It is here that the individual twisted pair
s of a telephone local loop
are terminated
. SAI are often recognizable as ubiquitous gray-green cabinets seen next to street
s. Here the individual twisted pair wires interface with F2 ( or Secondary Feeder Cable ) pairs and connect with F1 ( or Main Feeder Cable ) pairs at this point. F1 cables then go underground in conduit or along poles, usually to the nearest central office (CO) or remote switch, or first to transmission equipment such as a Subscriber Loop Carrier multiplexer and then to the CO.
SAI are used in suburb
an and low density urban areas, serving some of the same purposes that manhole
s do in high density urban areas. Besides a cross connect point, they sometimes contain a DSLAM or more rarely a remote concentrator
or both.
Telco can
A telco can is an outdoor enclosure or metal box where telephone local loop wires come together to be spliced into a larger cable that then runs to the Central Office. They are often just brown metal boxes on the street or side walk...
usually mounted on the ground on cable right-of-way
Easement
An easement is a certain right to use the real property of another without possessing it.Easements are helpful for providing pathways across two or more pieces of property or allowing an individual to fish in a privately owned pond...
s, but sometimes also on telephone poles. It is here that the individual twisted pair
Twisted pair
Twisted pair cabling is a type of wiring in which two conductors are twisted together for the purposes of canceling out electromagnetic interference from external sources; for instance, electromagnetic radiation from unshielded twisted pair cables, and crosstalk between neighboring pairs...
s of a telephone local loop
Local loop
In telephony, the local loop is the physical link or circuit that connects from the demarcation point of the customer premises to the edge of the carrier or telecommunications service provider's network...
are terminated
Point of appearance
Point of appearance is a generic term for any point in a telephone/data circuit from which a technician can test or pull stats. Some appearances are virtual, such as a Digital cross connect system computer terminal. Others are physical, like a punch down COSMIC frame where a technician can place a...
. SAI are often recognizable as ubiquitous gray-green cabinets seen next to street
Street
A street is a paved public thoroughfare in a built environment. It is a public parcel of land adjoining buildings in an urban context, on which people may freely assemble, interact, and move about. A street can be as simple as a level patch of dirt, but is more often paved with a hard, durable...
s. Here the individual twisted pair wires interface with F2 ( or Secondary Feeder Cable ) pairs and connect with F1 ( or Main Feeder Cable ) pairs at this point. F1 cables then go underground in conduit or along poles, usually to the nearest central office (CO) or remote switch, or first to transmission equipment such as a Subscriber Loop Carrier multiplexer and then to the CO.
SAI are used in suburb
Suburb
The word suburb mostly refers to a residential area, either existing as part of a city or as a separate residential community within commuting distance of a city . Some suburbs have a degree of administrative autonomy, and most have lower population density than inner city neighborhoods...
an and low density urban areas, serving some of the same purposes that manhole
Maintenance hole
A manhole is the top opening to an underground utility vault used to house an access point for making connections or performing maintenance on underground and buried public utility and other services including sewers, telephone,...
s do in high density urban areas. Besides a cross connect point, they sometimes contain a DSLAM or more rarely a remote concentrator
Remote concentrator
In modern telephony a remote concentrator, Remote Concentrator Unit , or Remote Line Concentrator is the lowest level in the telephone switch hierarchy.Subscribers' analogue telephone/PSTN lines are terminated on concentrators...
or both.
See also
- Enclosure (electrical)Enclosure (electrical)An electrical enclosure is a cabinet for electrical or electronic equipment to mount switches, knobs and displays and to prevent electrical shock to equipment users and protect the contents from the environment...
- Fiber to the telecom enclosureFiber to the Telecom EnclosureFiber to the telecom enclosure , also sometimes called fiber to the zone , is a standards-compliant structured cabling system architecture that extends the optical fiber backbone network from the equipment room, through the telecom room, and directly to a telecommunications enclosure installed in...
- Sub-loop unbundlingSub-loop unbundlingIn the telephony business, Sub-loop unbundling is the process by which a sub-section of part of the local loop is unbundled. 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...
- Telco canTelco canA telco can is an outdoor enclosure or metal box where telephone local loop wires come together to be spliced into a larger cable that then runs to the Central Office. They are often just brown metal boxes on the street or side walk...
- Demarcation pointDemarcation pointIn telephony, the demarcation point is the point at which the public switched telephone network ends and connects with the customer's on-premises wiring. It is the dividing line which determines who is responsible for installation and maintenance of wiring and equipment -- customer/subscriber, or...