Landline

A landline, or fixed line, is telephone service provided to a subscriber via cable or wire, i.e. metal conductors or optical fiber. The term differentiates a telephone service from the now ubiquitous wireless service. A landline allows multiple telephones to operate simultaneously on the same phone number. It is loosely described as plain old telephone service (POTS). Landline services are traditionally provided via the outside plant of a telephone company, consisting of analogue copper wire originating from a telephone company's central office, or wirecenter. Landline service often includes services that use Internet Protocol via broadband services. The outside plant comprises tiers of cabling between distribution points in the exchange area, so that a single pair of copper wire, or an optical fiber, reaches each subscriber location, such as a home or office, at the network interface. Customer premises wiring extends from the network interface ("NID") to the location of one or more telephones inside the premises. A landline can carry high-speed internet such as digital subscriber line (DSL) which links back to the digital subscriber line access multiplexer (DSLAM) within the central office, T-1/T-3, or ISDN. Subscriber's telephone sets connected to a landline may have a hard-wired handset, or it may be a cordless telephone, in either case it typically refers to the operation in relatively-fixed locations, such as a residence or office. Wired handset landline telephones do not require mains electricity to work.