what is a wan

introduction to wans
A WAN is a data communications network that spans a large geographic area such as a state, province, or country. WANs often use transmission facilities provided by common carriers such as telephone companies.
These are the major characteristics of WANs:

A WAN differs from a LAN in several ways. For example, unlike a LAN, which connects workstations, peripherals, terminals, and other devices in a single building, a WAN makes data connections across a broad geographic area. Companies use a WAN to connect various company sites so that information can be exchanged between distant offices.
A WAN operates at the physical layer and the data link layer of the OSI reference model. It interconnects LANs that are usually separated by large geographic areas. WANs provide for the exchange of data packets and frames between routers and switches and the LANs they support.
The following devices are used in WANs:

The Interactive Media Activity will help students become more familiar with WAN devices.
WAN data link protocols describe how frames are carried between systems on a single data link.
They include protocols designed to operate over dedicated point-to-point, multipoint, and multi-access switched services such as Frame Relay. WAN standards are defined and managed by a number of recognized authorities, including the following agencies: