An Overview of Computer Networks
My second degree, or should I say my second go through inside
the education system was in networking. I'm a certified Novell
and Microsoft engineer, not that I'm all that excited about the
fact. Networking is actually pretty mindless work once you learn
it. It's pretty much do it by the numbers based on what the
customer wants. After you hook everything up the software
installation is pretty straight forward. My 16 year old daughter
could do it or as GEICO would say, a caveman could do it.
In this article I'm just going to cover the basics of what a
network is and the types of networks. I'll go into more detail
in later articles.
A network is simply a means for computers to speak to each
other, or communicate with each other. With a network, computers
can receive emails from each other, send files to each other,
instant message each other and a variety of other things. This
is something that we take for granted today but there was a time
when networks were not so sophisticated and not all that
efficient either.
There are basically two types of networks.
The simplest network is a LAN or Local Area Network. This is
where all the computers in the network are located in one place
such as an office building. Within this type of network you have
2 ways to connect.
The simplest way is peer to peer. This is where 2 or more
computers are hooked up directly to each other. In other words
if you have 5 computers you would have computer 1 hooked into
computer 2 which would be hooked into computer 3 and so on. In
this type of connection each computer is dependent on the other.
So if computer 3 would go down then computers 1 and 2 would not
be able to communicate or exchange information with computers 4
and 5 and visa versa. That is the main problem with a peer to
peer network. Also in peer to peer networks the write process
between computers leads to data corruption problems. This is not
something they teach you in school but something you learn from
experience.
The more common type of LAN connection is client server. This is
where all the computers in the network are connected to each
other via a central computer. This kind of connection does
require more work in set up but is more efficient, carries data
better and if one computer goes down the others aren't affected.
However, should the server go down then all the computers on the
network would be affected as far as their ability to get
information from the other computers and the server itself.
They, however, would still be able to do work locally on their
own such as with a word processing program, unless the word
processing program was located on the server. Then it would not
be available. Usually, however, most applications are installed
on each computer. What is most commonly lost when a server goes
down is the ability to retrieve data that is common to everyone
in the network, say an in house database of all employees.
The second type of network is a WAN or wide area network. This
is where several LAN networks or even single computers are
connected to a much larger network. A perfect example of a WAN
is the Internet. This is where users from all over the world can
interact with each other through email, chat rooms and instant
messaging. WANs are enormous to say the least and are very
intricate in their design, requiring hubs from all over the
world to stay connected. One hub goes down and it can affect
connections for millions of people though there are protocols
instituted to reroute connections if a hub does go down.
The above is a very simplified overview of computer networks. In
future articles I'll go into detail on the hardware and software
required to set up these networks and some of the finer points.
Stay tuned.