Information Technology Reference
In-Depth Information
How does the
Internet work?
It's a Wednesday evening, and you've just sat down at your
computer. In a matter of minutes, you're scanning an ecommerce
site for you aunt's birthday present, you're composing an email
message to your professor via your school email account, you're
listening to your brother's radio show broadcast live from a college
hundreds of miles away, and you're using your computer for an on
line chat with a friend from home. Without the Internet, none of
these actions would be possible. Think about how much you de
pend on communicating via your computer—it may be much more
than you realize. When was the last time you actually mailed a let
ter in paper form? But what exactly happens to make email and
work with the Web possible? Where does the information reside,
and how do monitors know what to display. To begin, let's recall
what we already know about hardware and network organization.
On a small scale, the organization of computers into coherent net
works can follow simple principles discussed in Chapters 8 and 9. For
example, a small number of computers may connect to a single
Ethernet cable, forming a network segment. Segments, in turn, may be
connected in a hierarchical manner using routers. Organization of a
small group of computers within a school or company typically fol
lows a basic, coherent, and understandable structure. The Internet, on
the other hand, involves millions of computers, connected in complex
ways to a maze of local and regional networks. With so many comput
ers and connections, and with additions and changes happening con
tinuously, how can anyone know just how all of the pieces fit together,
and how can it possibly work?
293
