Original subtitles

Is my home router.

In this example it's a British Telecom or BT Home Hub.

Five Rodda I'm connected to the Internet using a DSL.

If you're not sure what a DSL Please don't worry we'll talk about it later.

It's essentially a way to connect through telephone lines to the Internet.

And as you can see here I have some devices connected to what's called a 2.4 gigahertz wireless network

and a five gigahertz wireless network.

They are different frequencies and wireless that you can use to connect to networks and there are benefits

and drawbacks of both.

I also have some devices connected via the physical network to this router so as an example I can surf

to Facebook does comb through my router on my local Windows PC I can use a program called Ping to test

connectivity to a remote network or remote site.

So in this example I'm pinging Facebook dot com.

And as you can see here I'm getting a reply from what's called an IP address.

We'll discuss IP addresses and what are called domain names in more detail later.

But essentially Facebook dot com is what's called a domain name and it gets resolved to what's called

an IP address by something called a domain name system server or DNS server.

So a DNS server has told my local PC that Facebook to come has this IP address and I'm able to test

my connectivity to that IP address using this program called Ping.

In this example I'm getting a reply from Facebook dot com.

So I've just tested that I have connectivity to Facebook dot com and I can even check the path to Facebook

dot com using an application called Trace search in Windows.

So I'm going to type traceroute.

Facebook dot com.

And what this does now is show me each hop.

Each device that I am hopping across or jumping across or going through to get to Facebook dot com

some devices will not reply to those protocol.

But as an example here you can see that I've hit a call BT router some way in the Internet and this

traffic is now being forwarded across multiple devices.

Two Facebook dot com and you can see that we hitting devices called C-1 and various other devices to

get to Facebook that come.

Don't worry too much about the details.

All I want you to see at the moment is that networks including your home network or DSL Rodda at home

allow you to connect to the Internet and then allow you to connect to sites on the Internet and elsewhere

networking is essentially the plumbing or the underlying infrastructure that enables devices to share

information with one another in its most simplest form.

You may have a PC and want to share a file with someone else.

So your laptop is able to access a file shared on a PC across a physical cable or more and more these

days using wireless.

Another example may be a printer you may have a printer and want to print to that printer across a wireless

network at home or by physically connecting a cable to the printer.

Networks essentially allow for the sharing of resources such as files between computers or printers.

So this printer could except print jobs from multiple PCs or even a phone.

These days networks allow us to make voice calls using applications such as WhatsApp and Skype.

They are essentially the plumbing allowing you to connect one device to another.