Leased Line: A communications medium described as a dedicated telephone line reserved for the permanent use of communicating between two points.

Local Area Network (LAN): A data communications network confined to a limited geographic area with moderate- to high-data rates. The area served may consist of a single building or a cluster of buildings. It is owned by its user, and does not use common carrier circuits, although it may have gateways or bridges to other public or private networks.