When we talk about network geography,
we're going to start with our smallest networks
and work our way out to our largest networks.
The smallest one we're going to cover is known
as a personal area network or PAN.
It's the smallest type of wired
or wireless network we can use.
And it usually covers about 10 feet
or less, so about a couple of meters of distance.
Now, some examples
of personal area networks would be things
like Bluetooth and USB.
Bluetooth is a great example of one.
It operates at about 10 feet or three meters.
And if you have your phone in your pocket
and you get in your car and it starts transmitting music
from your phone wirelessly to your radio in your car,
that's only about three or four feet away, right?
This is an example of a personal area network
because you have a connection between your car stereo
or radio with your cell phone.
Now, what about your USB connections?
Well, those can be personal area networks too.
If I take a USB hard drive
and I connect it to my laptop,
that's actually a serial connection
and it's considered a network.
It's actually going to be a personal area network.
If you have an older standard like Firewire
for your video cameras or a webcam
and you plug it in, these would also be considered
a personal area network.
Now, the way I like to think about this is if I put my arms
out to my side and I spin into a circle,
anything I can touch,
that's about my personal area network distance,
something around there or maybe a little bit more.
Now, the next one we have as we get
to a larger network is called a LAN.
This is a local area network.
If you worked in an office building,
you probably had a LAN at work.
It connects components in a limited distance,
generally up to about a hundred meters or 300 feet.
Each segment can only go about 100 meters
if you're using cat five cabling.
But if you're going to use fiber optic cabling,
you can actually go further.
We'll talk about distance limitations when we get
to the ethernet fundamental section.
But for right now, when you think about a LAN,
think about it being a small office
or one floor of an office building.
Now your networks can be consisting of either wifi
or ethernet, depending on how you want to set them up.
If you're using ethernet,
you're going to be using the IEE 802.3 standard.
Now, if you're using wifi,
you're going to be using the IEE 802.11 standard.
We'll talk specifically about these standards
in a future lesson as we dig deeper into the protocols
and standards.
As you're going through the course,
anytime I mention a standard like 802.11
or 802.3, you should write that down
with a word next to it that reminds you
what that standard is used for.
So in my notes, I'd have 802.11 wifi,
802.3 ethernet, something like that.
This will help you out a lot on the exam
if you have that cheat sheet at the end
that you can study right before the exam.
Now, what are some examples of a LAN?
Well, the internal wired
or wireless network in your office building
or in your school or in your classroom,
these are all local area network connections.
In fact, if you're sitting at home right now
watching this video,
you're sitting on your local area network
inside your house, making a connection between your devices,
your printers, your other laptops, your desktops
that are all inside of your house as part of the LAN.
Now the next one we want to talk about is going to be called
a campus area network or CAN.
Now, a campus area network is a building-centric LAN
that's spread across numerous buildings in a certain area.
So if you're at a college or a business park
or an industrial park and you have three
or four different buildings, they may all be linked together
in what's called a campus area network.
This can cover several miles
and across many different buildings.
For example, I teach at several different colleges,
and each of those colleges has a campus area network
that spans the entire university.
And so no matter which building you're in,
each building has its own LAN,
local area network that you connect to.
But then those lands are connected together
to form this campus area network.
Now, examples of this, again,
are going to be things like college campuses,
business parks and military bases.
All of these form what is known
as the campus area network or CAN.
So up to this point, we covered our personal area network,
the small space around us.
We covered the LAN, usually the area
of our house or our apartment.
And then we covered our campus area network
where we connect a couple of buildings together
that are within a couple of miles.
The next one goes even further out
and we're going to talk about it.
It's called a MAN.
A MAN is a metropolitan area network.
This is going to connect locations
that are scattered across the entire city.
This is larger than a campus area network,
but it is smaller than a global wide area network.
And so this can cover an area up to about 25 miles
or maybe even a little bit bigger
depending on the size of your city.
So let me go back to my example.
One of the colleges I teach for is a community college.
They actually have six different campuses
spread out across our city.
Each of those campuses has a campus area network,
but each of those campus area networks
are also connected together
to form a metropolitan area network.
So all of our campuses are in one large university network.
Other examples of this might be if you look
at your city's department,
like the Department of Motor Vehicles
or the police department, they may have lots
of locations dotted across your cities
and they're all connected together to form one network.
These are some great examples of what a MAN might look like.
And this brings us to our last one, our biggest network,
which is known as the Wide Area Network or WAN.
Now a wide area network
connects geographically disparate internal networks.
So this can consist of lease lines
or virtual private networks
that are tunneled over the internet.
Now, if you don't know what those two terms are,
don't worry about that right now.
We're going to go into both of them later on
in the course in a lot of depth.
So for right now, I want you to focus on the fact
that a WAN covers a large geographic area.
This may be across your state, across your country,
or even across the world.
For example, we actually look at the internet as a WAN.
It is a wide area network.
In fact, it is the largest wide area network available.
So if I'm sitting in my office and I'm recording this
and I'm going to upload it to a file server
that you're going to access from your home
wherever you are in the world, well,
that's going to happen over a wide area network connection.
Now, another important thing
to think about when we talk about
a wide area network connection
is the fact that they don't always have
to be public like the internet is.
In fact, let's take an example of a company
that has an office in New York and an office in California.
Now, each of those two locations has their own
local area networks, but if we wanted
to connect them together over a private intranet,
we could do that using a wide area network connection
because we're taking this very large network
going across the entire country and connecting it together.
So we have these two local area networks,
but they're still tied over this larger WAN link.
A good example of this
is the government of the United States.
They have offices all over the country.
In fact, all 50 states spanning three or 4,000 miles, right?
All of those can be connected
through a private wide area network connection.
So they have a wide area network
that is made up of all of these smaller networks.
So when we look at network geography, I want you
to remember the distance involved.
So as we start thinking about this,
we have our smallest network, the personal area network,
and then we move out and we get to our local area network,
and then we go even further and we start getting a couple
of buildings with our campus area network.
And then we connect a couple
of those buildings together across the city,
and that becomes a metropolitan area network.
And then finally, we go across the state, the country,
or even the world with our wide area network.
So when it comes down to it,
if you can remember these distances
that we're talking about, smallest to largest,
and what these networks stack up, you're going to be able
to answer any question you get as far as PANs,
LANs, CANs, MANs and WANs on the exam,
because you'll know how far they can go
and what type of networks that they're using to do it.