What is a computer network? Well, first, what is a network? The definition of a network is “A group or system of interconnected people or things”.
So, it would be fair to say, a computer network would be “A group or system of interconnected computers” right?
And that’s exactly what it is. A computer network is anything where more than one computer is connected.
Traditionally, a computer network would consist of desktop computers, servers, printers, etc.
These days, we live in a connected world. We still have desktops, servers, and printers, but now we have a vast number of smart devices connected to our networks as well.
Most of you will have a mobile phone, maybe a tablet. Security cameras and even smart lighting systems can be found on networks! And the list goes on and on!
So, let’s look at some basic networks and see what they look like.
First, one that should be familiar to most of you.
Here we have a switch, a router, a wireless access point, a desktop, and a phone, all connected to the same network. This is a pretty common home network setup.
Note: In most home networks, the switch and wireless access point will be built into the router.
Generally speaking, any network in a single area is called a Local Area Network or LAN.
The LAN is usually connected to the ‘outside world’ using a socket in the wall that your Internet Service Provider (ISP) installed.
This socket connects you to something called a Wide Area Network or WAN. The purpose of a WAN is to connect separate LANs together.
The most obvious example of a WAN would be the internet. However, businesses might have private WANs to connect multiple offices together.
Now let’s look at a more business type network.
We still have switches, access points desktops, and routers, but usually on a much larger scale.
All of the office computers will plug into either a wall or floor socket. These sockets will have cables running either through the ceiling, floor or walls back to a special room called a wiring closet.
In the wiring closet, all these devices will connect to a stack of switches which are mounted on to racks.
Depending on the size of the network, there may be multiple wiring closets which all connect to each other.
Keep in mind, this has been simplified just to give you the general idea.
Lastly, we will look at another familiar network that might not be so obvious.
I’m sure you all have smartphones of some sort. Now, these phones generally have internet access via 3G, 4G, and even 5G.
Well, you could think of these as basically a giant wireless network for your phones.
Somewhere close to you there will be a giant tower that allows you to connect and get internet access. The closer to these towers you are, the better the signal you are likely to get.
Why Do We Need Networks?
So, the next logical question is, why? Why do we need networks?
The beauty of networks is that we can share resources. If I have a file, and I want to send that file to someone, I can. They can also share files with everyone else.
We can have shared printers that everyone can use. We can even have servers that could store these files for us.
Of course, files sharing is just one example, this could be pretty much anything.
And all of this is before we even start to talk about the internet, which by the way is just a giant network.
With the internet, we can search for anything we want. We literally have the worlds knowledge at our fingertips.
We have Email, social media, we can message our friends, hosted computing, telephone calls over the internet and of course, awesome YouTube content!
So, Networking has changed the world and how we live. It’s a topic I still get excited about and there is no shortage of new things to learn.
We will go over a lot of this in more details as we go but that enough for now.