networking by ashrafp


									Everyone is familiar with the internet these days, but how does it work? The internet is
essentially a vast collection of networks linked together. So, to get an understanding of
the inner workings, we need to know some of the basic principles of networking.

Let's start with the hardware, specifically the cabling. The most widely used network
architecture is known as ethernet, and there have been several popular types of cabling to
implement it. In the early days, the cables that were used were about a half inch thick,
making them clunky, not very flexible, and generally a pain to work with. The next type
of cabling to gain popularity was coaxial, the same thing you use to connect your TV to
the cable outlet in the wall. While it wasn't nearly as bulky as its predecessor, it still had
its drawbacks. Coax (also known as 10Base2) was typically implemented in a daisy-
chain configuration, meaning that if the cable was compromised in some way, every
device on that particular section of cabling would lose connectivity.

The cabling we use today, known as 10BaseT, is far easier to implement. It resembles
the cable we use to connect our phones to the wall outlet, and therefore possesses many
of the same desirable characteristics - it's thin, lightweight, flexible, and easy to work
with. Although the connectors look much like that of ordinary phone lines, they are not
the same. Telephones use connectors known as RJ-11, while network cables use
connectors known as RJ-45. The most obvious physical difference between the two is
that RJ-45 connectors are somewhat wider than RJ-11 connectors.
Alright, so much for the mundane cabling. I'll return to some of the other hardware later
on, but for now let's move on to the software side of things. Networks employ something
called protocols, which are standards that dictate how data is transmitted and received.
While there are many of these protocols, the most widely used is TCP/IP, which stands
for Transmission Control Protocol / Internet Protocol. As the name suggests, this is the
protocol utilized by the internet, so your system will also have to utilize it if you want
internet connectivity. Although the inner workings are rather complicated, recent
versions of Windows do a pretty good job of setting this up for you, and ISPs (Internet
Service Providers) have also taken steps to make connecting a more or less automated

Now, let's finish up the hardware. Besides the cabling, at a minimum you will need a
computer and a modem for Internet connectivity. If you use dial-up networking,
connecting a phone cable from the modem to the wall phone jack is the extent of the
hardware connection process. If you use broadband networking (cable, DSL, etc.) your
computer will need to have a NIC (Network Interface Card) installed, although most
modern systems have this feature integrated into the motherboard. With both cable and
DSL (Digital Subscriber Line), the modem is connected to the NIC with a network cable.
In the case of DSL, the modem is connected to the wall phone jack with a phone cable,
and in the case of cable the modem is connected to the wall cable outlet with a coax
As for other hardware, there's really only one device that is typically implemented by
home users and small businesses - the router. As the name suggests, it routes network
traffic among the devices connected to it, and is typically used to allow two or more
computers to share an Internet connection and to connect those computers to one another.
These devices are available in two varieties - wired and wireless. The wired versions
currently sell for $50-60 and the wireless versions only cost $5-10 more. This allows
every connected computer access to the Internet and also allows them access to files and
printers residing on the other systems. In addition, they also typically implement a
firewall, which protects all connected devices from attacks via the internet.

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