9
Introduction to Local Area Networking
A Local Area Network (LAN) is typically an Ethernet-based network that con-
nects several computers together over a small area such as a building or group
of buildings. LAN’s can also be connected over large areas. A collection of LANs
connected over a large area is called a Wide Area Network (WAN).
There are many types of media that can connect computers together. The most
common media is CAT5 cable; UTP or STP twisted pair wire. Each computer
must have a Network Interface Card (NIC), which transfers the data between
computers. A NIC is usually a 10/100Mbps Fast Ethernet adapter.
Most networks use hardware devices such as hubs or switches to transfer
data between computers. A hub receives data arriving through each port and
forwards the data to all other ports. A switch is more sophisticated, in that a
switch can determine the port (or corresponding computer) that each packet of
data is supposed to be delivered to. A switch minimizes network traffic and
speeds up communication over a network.
There are many types of scenarios to consider which could affect the operabil-
ity of a network. Some of these issues are discussed in the manual under the
Networking Basics section.