By definition, a local area network (LAN) is limited to a specific area, usually an office, and can-
not extend beyond the boundaries of a single building. The first LANs were limited to a range
(from a central point to the most distant computer) of 185 meters (about 600 feet) and no more
than 30 computers. Today’s technology allows a larger LAN, but practical administration lim-
itations require dividing it into small, logical areas called work-groups.
A workgroup is a collection of individuals (a sales department, for example) who share the
same files and databases over the LAN. Figure 1.1 shows an example of a small LAN and its
workgroups.
