Page 74 - DCAP104_EXPOSURE_TO_COMPUTER_DISCPLINES

Unit 4: Introduction of Networks

4.3.5 Wide Area Network Notes
A wide area network (WAN) is a computer network that covers a large geographic area such as
a city, country, or spans even intercontinental distances, using a communications channel that
combines many types of media such as telephone lines, cables, and air waves. A WAN often
uses transmission facilities provided by common carriers, such as telephone companies. WAN
technologies generally function at the lower three layers of the OSI reference model: the physical
layer, the data link layer, and the network layer.

Figure 4.7: A WAN Structure

4.3.6 Campus Network
A campus network is a computer network made up of an interconnection of local area networks
(LAN’s) within a limited geographical area. The networking equipments (switches, routers) and
transmission media (optical fiber, copper plant, Cat5 cabling etc.) are almost entirely owned (by
the campus tenant / owner: an enterprise, university, government etc.).
In the case of a university campus-based campus network, the network is likely to link a variety of
campus buildings including; academic departments, the university library and student residence
halls.
Figure 4.8: A Campus Network Structure

LOVELY PROFESSIONAL UNIVERSITY 67