It's good to read this is good to read Poodle, what's in your hand?
OK, you know what?
Cable is that?
Great cable.
A great cable.
What do you use it for a computer when you plug it in on this laptop?
Well done, so that's an Ethernet cable that you plug into a laptop, take it out.
Do you think it's easier to use an Ethernet cable or is it easier to use wi fi?
WI fi?
WI fi is much easier.
I see that you're doing a lot of reading here.
What are all these books about?
You're learning about Wireshark.
Wow, so you really learning about networking?
You're a great networker, aren't you, Butel?
Let's talk about basic networking.
Now, networks can get really big, biggest network that we know of today, unless you know about aliens
having a bigger network somewhere out there in space is the Internet.
So the Internet is the biggest network that we have on Earth today.
But a network doesn't have to be very big.
A small network would simply consist of two computers.
So in this example, I've got two Windows laptops.
Previously, as I mentioned, I could copy a file onto this USB drive, so copy a file from this computer
onto the drive and then put it into the second computer and then copy the file onto this computer.
So that's how I could share information from one computer to another without a network.
But in its most basic form, a computer network will use something like a cable.
This is a copper Ethernet cable.
This is what's called UTP or unshielded twisted pair copper cable.
You've probably come across these types of connectors in the real world.
This is known as an RJ 45 connector.
Now it does have a different name, but we won't get into that right now.
This is commonly referred to as an age 45 connector.
So if you talk about age 45 in a networking context, people will know what you're talking about.
So I could, as an example, take this cable and then plug it in to this laptop.
Now, this is an older laptop, so it has a built in network interface card.
So I can take an order 45 connector and plug it directly into this computer.
This laptop, however, on the right is a newer laptop.
And like a lot of newer laptops and Mac books, it doesn't have any age 45 network interface cards.
Now, network interface card or NEC is how we connect to the physical network or wireless network.
It's basically a card that's either inserted into a laptop or is built into a laptop that has what's
called a Mac address or media access control address on Ethernet, which is the technology that we generally
use today on wireless devices are known by what's called a Mac address.
So here's an example of a very old network interface called this network interface called supports older
technologies such as 10 Base five, the first type of Ethernet that was ever developed, supports 10,
beats two.
And it also supports an age 45 connector using UTP or unshielded twisted pair.
This would be inserted in a computer.
Now, that's really old.
Today we have more modern network interface card such as this one only supports Arjay 45.
It's a lot smaller.
And then this is an example of a network interface card that would go in a Raspberry Pi.
As an example.
This only supports Wi-Fi.
I mean, you can't connect Ethernet to this.
So on a laptop like this, what I could do is I could use a USB to age 45 network interface card.
So this is an adapter that converts the USB to Oduye 45.
And then what I can do is plug the Ethernet cable in here.
And what I have now is essentially a network.
I have a network consisting of two Windows computers and I'll now be able to share files from one computer
to the other.
But it's a lot of hassle, a lot of work setting this up.
But that's an example of an Ethernet network where I have two computers connected using a physical cable
in this example, what's called Cat five ecolabelling unshielded twisted pair of 45 connectors on the
end.
That's an example of a very basic network.
But if I told a young person today, so let's say a teenager to set up a network between their devices
using cabling like that, they'd probably think I'm crazy because what we tend to use today is Wi-Fi.
WI fi is an example of using the air for transmission of data from one device to the other makes life
a lot easier in many ways.
People today expect that it's easy to share information from one device to another.
In this example, I've got two iPhones.
I mean, how would I physically plug a cable into one of these phones?
They don't have Arjay 45 connectors.
I don't have a USB B to Ethernet port that I can use to plug an Ethernet cable into this iPhone.
I could use the lightning port, but people today wouldn't be happy with that.
They expect it to just work and work very easily.
And the technologies that we're going to be using to share files from one phone to another are Wi-Fi
as well as Bluetooth.
So as an example on this phone, here's a picture.
I'm going to share that picture using airdrop.
Notice, it tells me that Bluetooth is off.
I need Bluetooth to allow this device to share the fall with other devices, not picked up two devices.
I've got a iPhone blue, which is the phone on the right, as well as my MacBook, which is in front
of me.
So I'm going to select the iPhone.
And what happens now is the fall is shared from one phone to the other.
So by leveraging Wi-Fi and Bluetooth, I can share a file from one phone to the other.
That's an example of file sharing.
I'm sharing a file which in this example is a picture from one phone to the other.
And the medium or media that I'm using is the air.
I'm sharing data from one device to another using Waze through the air, just like I'm speaking to you.
And what's happening is a microphone is picking up the waves that I'm making with my vocal cords, basically
speaking into the air, making waves that's then digitized by my microphone.
Same idea here.
A digital file on a phone is modulated in the center, sent through aways from one device to the other.
This device modulates it and creates the file on the other side.
So I'm transmitting a resource, a file from one device to the other using the air in this example.
That's an example of a network.
I've got a network of two devices where one device is sharing a resource with another device.