Local loop

In telecommunications the local loop is the wiring between the central office ("telephone exchange" in British English) and the customer premises' demarcation point.

The local loop connection is typically a copper twisted pair carrying current from the central office to the customer premises and back again. Individual local loop telephone lines are connected to the local central office or to a remote concentrator.

Local loop connections can be used to carry a range of technologies, including:

• analog voice (for traditional analog telephony)
• ISDN
• ADSL and analog voice
• HDSL[?]
• SDSL
• VDSL

The term "local loop" is also sometimes used loosely for any "last mile" connection to the customer, regardless of technology. Hence the phrase "wireless local loop".

See also:

• loop disconnect[?]
• DTMF
• E and M signaling[?]