Wireless Networks

Wireless Networks or WLANs.

In this section of the course,

we're going to cover wireless networks.

Now wireless networks are great

because they extend your physical network

into the wireless domain.

It can allow your users to run wherever they want

inside of a given coverage area.

If you think about a college, for instance,

you might have an entire campus,

including numerous buildings,

the outdoor spaces,

and everywhere covered by this wireless network.

You can just take your laptop,

open it up at a picnic table

and gain access to the world.

Now, the popularity of wireless networks keeps increasing

over and over and over again.

Back in the late 1990s,

there were just a few places that had wireless networks.

Nowadays, though, we expect wireless networks

pretty much everywhere we go.

Heck, we even have them in airplanes

as we fly across the globe.

Anytime you go to a coffee shop or a restaurant,

you can usually expect to be able to pull out your phone

and find a wireless network.

They're very convenient to use,

and they expand your network throughout an entire room,

a floor, a building,

or an outdoor space using this wireless technology.

Wireless networks are definitely here to stay.

So in this section of the course,

we're going to be focusing on domains two, four and five,

specifically objectives 2.1, 2.4,

4.2, 4.3 and 5.4.

Objective 2.1 states that you must compare and contrast

various devices, their features

and their appropriate placement on the network.

Objective 2.4 states that given a scenario,

you should be able to install

and configure the appropriate wireless standards

and technologies.

Objective 4.2 states that you must compare

and contrast common types of attacks.

Objective 4.3 states that given a scenario,

you must apply network hardening techniques.

And objective 5.4 states that given a scenario,

you must be able to troubleshoot

common wireless connectivity issues.

All right, that is a lot of different objectives,

but really in this section,

we're going to cover the fundamentals of wireless networks,

how they're configured,

how to use the different frequencies and antennas

and how to best secure them.

When we look at wireless networks,

the most common type

is what we refer to as 802.11 or WiFi.

Now I want you to write that down in your notes.

When you see 802.11,

this is the standard for wireless networking,

known as WiFi.

There are several standards underneath that,

and we're going to talk about them in this section.

This includes 802.11a, b,

g, n, ac and ax,

but we're going to get into those

in a separate video.

There are also other wireless options out there

that you may find in use.

Most of those are going to be used

for Personal Area Networks,

things like Bluetooth, Infrared,

Near-field communications,

Ant+, and Z-Wave.

On the other hand,

we also have some wireless options that exist for us to use

in Wide Area Network connections,

things like Cellular and Microwave,

Satellite and High-frequency radio networks.

But if you're dealing with a Local Area Network,

you're almost always going to be using WiFi,

which consists of those 802.11 standards.

Now, when you're dealing with wireless networks,

there are really two ways you can do it.

You can operate in what's known as Ad-Hoc mode

or Infrastructure mode.

With Ad-Hoc mode, each wireless device

is going to communicate directly with the other,

without the need of a centralized access point.

This is very much like a peer to peer connection

where two devices don't need to rely on a centralized switch

or server to communicate.

Now, Ad-Hoc mode works great

if you're doing something simple like gaming

or doing a simple file transfer.

But if you want to be able to connect to

and be able to get out onto the internet,

you're probably going to need to use something

better than Ad-Hoc.

And that is why most people use Infrastructure mode.

Now Infrastructure mode is when you communicate

through a centralized access point or router,

and it's going to look a lot

like a star topology, essentially.

All of your devices

are going to connect back to the access point,

and then from there they gain access to your network

or the internet.

This is the traditional WiFi

that you're probably used to in a coffee shop,

your home or your office,

because everything's going back into this infrastructure

where you have other network infrastructure

like routers and switches and firewalls

that support it

and help get your traffic out to the right place.

Now, when you're using Infrastructure mode,

you have to have some kind of a device

to bring all those wireless devices

and connect them to your physically wired network.

This is where the concept of a WAP

or Wireless Access Point comes into play.

Now, this is commonly referred to as a WAP,

like I said,

or you might hear it abbreviated as an AP

or Access Point.

These devices are used to extend your wired network

into the wireless domain.

Now a Wireless Access Point

is not going to interconnect different networks though,

because it's not considered a router.

Everything that connects to that Wireless Access Point

is going to be treated as if it was connected to a hub

using copper cables.

Essentially, this means that all your wireless devices

are going to be in the same collision domain

and the same broadcast domain.

So what's the benefits of using an access point?

Well, it's going to allow you to connect your wired network

into the wireless domain and expand your access.

When you do this,

you can have one or multiple access points

that are connected to your domain.

For example, you can see that circular device here.

That's actually the access point I'm using in my building.

Because our building is a little bit larger

and we have concrete walls,

we have to have multiple access points working together,

so we don't have a drop in coverage

as we walk through the building.

We have three different floors of the building

and each one of those has an access point on it

that gives us full coverage throughout that building.

These access points all work together

and they hand off the client

from access point to access point,

as you walk around the building

or go up or down the stairs.

Now we're going to talk later

about how this actually works

and how these handoffs happen

from access point to access point in a separate video.

For the exam, I want you to remember

that Wireless Access Points extend your wired network

into the wireless spectrum.

So they're going to act like a hub

and a media converter,

converting those radio frequency waves

to ones and zeros,

that can be transmitted

over copper cabling of your wire network.

Next, we have what's referred to as a Wireless Router,

and this is a slightly different device.

Now what's the difference between a wireless router

and an access point?

Well a wireless router

is going to act as a gateway device.

And it's also going to act as a base station

for your wireless networks to communicate with.

This is the big difference here.

When you're using a wireless router,

instead of an access point,

you have this additional routing capability

inside the device.

Now, most people when they go to the store

to buy a wireless device,

they're going to get sold something marketed

as a wireless router.

This is really a combination of several devices,

all in one box.

For example, you can see here

that I have a Quantum Gateway Wireless Router from Verizon.

If you have a Verizon Fios connection in your house,

this is likely what you're using

to connect to the internet.

This one is a singular device

that has a wireless access point built into it.

And in addition to that,

there's a router built into it.

And in addition to that,

there's a four-port switch built into it,

and it also has a firewall built in,

and it has a fiber modem.

All of these different devices

have all been combined into the single small office,

home office user device

that is now sold as a wireless router

or a wireless gateway.

So on the exam,

remember a wireless access point is just that.

It's an access point

that's going to extend your physical network

into the wireless domain and it acts at layer one,

but a wireless router or wireless gateway

is going to be a combination device

that acts as a wireless access point and a router

within the same box.

In the last video,

we talked about the fact that there was Ad Hoc

and Infrastructure mode,

and I said, we'd come back to that and dig a little deeper.

Well, in this lesson, we're going to do that.

First. we have Ad Hoc mode.

Now, when we use Ad Hoc mode,

we're actually using what is called the IBSS

or the Independent Basic Service Set.

You'll notice in this diagram

that I have a wired network on the first floor

and I have two devices connecting wirelessly

to each other, on the second floor.

Notice, these two devices on the second floor

are not talking to anybody on the first floor.

They are a separate network and they are talking only

in a peer-to-peer configuration using that Ad Hoc mode.

So these devices,

because they're in an Ad Hoc mode,

have no access to the internet

and no access to the local area network.

They're operating solely in Ad Hoc mode,

in that peer-to-peer method.

Next, I want to show you what it looks like

when you have BSS, or a Basic Service Set.

Now, notice my second floor devices

are connecting wirelessly down to the wireless access point,

and the device on the first floor

is actually connecting wirelessly

to a wireless access point, as well.

Then there's a hard line cable

going between the access point and the switch.

This is how we're going to connect all of our stuff

in this small office, home office environment.

Now in your house, if you have wifi,

this is most likely what you're doing.

You have one access point that's connected to your network,

and that's how it makes a connection out to the internet.

Now, this is our first Infrastructure mode.

This is what we call the Basic Service Set.

Now, the second one we have

is what's known as an Extended Service Set or ESS.

Now, notice here because this building is so large,

I have two different wireless access points,

I have one for the first floor and one for the second floor.

Both of these access points are hardwired back using either

a Cat5 or a Cat5e cable,

to a switch on the first floor.

They're now providing Service wirelessly

to their designated floor,

either the first floor or the second floor.

Now they're working in conjunction with each other

so that we have a full coverage over the entire building,

and they're all going to have the same wireless network name

when you look for it using your device.

So, if you come to my house, for instance,

we have a network called Dion.

We have several access points spread throughout the house,

operating in what's known as the Extended Service Set mode.

The reason why, is we wanted to have good coverage

for everyone in the house, no matter where they're standing.

If you're down in my basement,

or you're up on my main level,

you're still going to get good Service

because of our Extended Service Set.

Now, the way you use this is through what's known as

the ESS, the Extended Service Set.

They all work together.

This gives you multiple access points

to give you good coverage across an entire building.

If you go to a large building for work,

or you go to a college campus, they use this all the time.

The reason why is, that a single access point

can only cover maybe 100 or 150 meters,

but by using multiple access points,

I can cover an entire college campus.

As long as they're all working together,

the end user just sees the one network as they roam around

the campus and move from building to building.

The next concept we need to talk about

is what's known as a Mesh Topology.

We covered this all the way back in our topology lessons,

back in the beginning of the course.

Now with a Mesh Topology,

they may not use a centralized control mechanism,

but instead it's going to combine a number of different ways

of doing wireless networks, into one manner.

So, you might use microwave, or cellular, or wifi

or any other type of wireless technology

and make one coherent network with it.

It works kind of like an ESS,

the Extended Service Set does for wifi,

but the difference here is we're not just using wifi,

we're combining other wireless mechanisms too.

So for example,

I have my laptop connecting wirelessly

to a wireless access point,

then that wireless access point connects

to a satellite connection, which is wireless

up to a satellite.

That satellite may then go up to the satellite

and down to a ground station,

and that ties back into a switch,

and then to another machine.

Now, if I look at the bottom of this diagram,

you can see where the internet is coming from.

It's connecting a wired internet

through a router, to a wireless access point.

Now there it's going into a TV and a laptop

and things like that.

Now, all of this can make up one big Mesh Topology,

as we connect through different devices using wifi,

and microwave and cellular

and other wireless technologies.

Now, if we want to take this a step further,

take a look at this diagram.

I showed you this in a smaller version back

in the Mesh Topology lesson as well,

but you can see here how we have 802.11 wifi zones,

and we have high-frequency antennas,

and high-gain antennas that cover vast distances.

We have satellite, we have microwave,

we might even have WiMAX in here.

All of this can work together to give us this perfect mesh

that covers a large range of areas, as we go through.

Now, as I mentioned before,

when we talk about Mesh Topologies, this is very popular

to use, in a disaster recovery situation.

If you lose landlines and they've gone down,

we need to start building up frequencies for us to be able

to use in a quick manner, and be responsive to a situation.

So, if there's an earthquake or a hurricane or a tornado,

the responders might come in and bring a satellite,

and a microwave link, and wifi access points,

so they can set up a network

and communicate that information back out

to the unaffected areas and get more assistance.

Next, let's talk about access point placement

because careful planning and placement

of your access points is really important

to make sure you don't have interference

and you can prevent network outage issues.

This will become very clear to you during

the troubleshooting section of this course, as well.

Your coverage area needs to have an overlap between

your different access points,

to make sure you don't have holes in your coverage

and to make sure everything is working properly.

So here on the diagram, for instance,

let's say that we have this office building

and we want to cover all of it with wifi.

Now, the way wireless radios work is that wherever

you put it, it's going to start in the center

and then access everything out,

in a circular pattern around it.

In this building, we have four different access points

that we're going to cover the entire building,

and I don't want to have any drops

as I walk from one room to another,

so, I need to have an overlap.

We want to have an overlap between the coverage zones,

but not an overlap in our frequencies.

If you know anything about radio frequencies,

you'll know that if we have two people transmitting

on the same frequency at the same time, that causes jamming

and collisions, and will drop the signal.

So if I'm using the 2.4 gigahertz spectrum,

which is used by wireless B, G and N,

we want to make sure we have an overlapping coverage

of 10 to 15 percent.

Now, as I blow up this diagram here,

you can see I have four wireless access points,

and they're all operating on channels, 1, 6 and 11.

That is going to make sure that no two circles

are touching, using the same channel frequency

because channel 1 uses a different frequency than channel 6,

and channel 6 uses a different frequency than channel 11.

Now, you'll see that channel 6 is on the left

and it's touching channel 1 and channel 11.

Channel 6 on the right,

is touching channel 1 and channel 11.

So again, I can't have channel 6 and channel 6 overlapping

because that would give me frequency issues

and we would have collisions and drop coverage.

Now, when we move into the newer spectrum of 5 gigahertz,

which is used by wireless N and wireless AC,

you're going to want to have overlapping coverage as well,

but because the way that we do this,

and there's some bleed over,

we want to make sure there's

no identical channels sitting next to each other, either.

These channels actually need to be separated

by at least two cells as you're designing your networks.

So, as we designate these cells

like a honeycomb pattern using the 5 gigahertz spectrum,

we want to make sure that we're making sure

there's at least two cells in between each of those

that have the same channel.

Now, this is different than the circles we used inside

the 2.4 gigahertz.

So if you look at my screen here,

you can see I have channel 36 in the upper-left corner,

and then you get there and you go through channel 52

and channel 54,

and then you finally come back to channel 36, again.

Notice I had at least two spots in my honeycomb

before I repeated a channel.

We have this honeycomb pattern and we keep this separation

because that's going to give us much better coverage

with no drops and no interference.

Now, when you go out and you do your site survey

and you start looking at a building,

and you start seeing where the access is,

you want to figure out where you have good coverage

and where you have bad coverage,

and you can actually produce what's known as a heat map,

and map out all those coverage zones,

and overlay it on top of your floor plan.

Now, in this example, we have a building

and you've seen that I've done a wireless survey

to determine my coverage areas.

Where it's blue, that's where the access point is,

and the blue is a really, really strong signal.

Green is a good signal.

Yellow is getting a little weaker

and red means I'm really weak, or out of signal.

Now there's a couple of offices in there

and in the middle of the diagram,

there's a red coverage area.

If I wanted to improve that,

I would move another access point into that region,

but overall, this has pretty good coverage,

except for that stairwell in the center of the screen.

Now you'll notice outside the building,

we do have red as well.

Now that's actually a good thing from security

because I don't want a lot of signal bleed

going outside of my building.

Now, what is considered a bad thing here?

Well, if you look in the bottom-center of the diagram,

we have green, yellow, and orange in the parking lot.

That means if I drove into this parking lot,

I could connect to your building's wireless network.

Now that's not necessarily a good thing,

and that's bad from a security standpoint

and I'd have to think about that as I'm building out my map.

and so maybe I want to take that access point

and move it a little bit more towards

the center of the building, and that will help alleviate

and bring some more red spots on the outside of the building

and alleviate those red spots

that were in the inside of the building.

We'll talk more about that as we go into wireless security,

later on in the course,

but for the time being, I want you to remember

that if you do a site survey, you may produce a heat map

that shows where your hotspots are,

where you have good coverage inside of a building

and where you have weak coverage,

and you can move your access points around

to give you a better coverage map.

Now, what is another great way

to get additional coverage, besides implementing something

like ESS with the Extended Service Set model.

Well, if you don't want to put up a full access point,

you can get what's called a Range Extender.

Now, what a range extender is,

is a specialized device that helps you overcome some

of your distance limitations.

Essentially it has a receiver and a transmitter,

and it's going to receive in the wireless signal

that's already there

and then transmit it out the other side,

as it does this, it's going to amplify your signal

and extend the reach of that wireless signal.

These are very small devices

and all you need to do is plug them into the wall

for them to work.

For instance, here,

you see the net gear displayed on the screen

and it has two antennas.

One of those is for listening

and one of those is for sending out the information.

If you have a large house

and your router is down in your basement,

you can actually use a wireless access point

down in the basement,

and then you might put one of these range extenders

in the stairs, to get that signal up into the second floor.

This can actually get your signal from the basement

and rebroadcast it upstairs like I said,

and essentially this becomes a wireless repeater.

Just like we would use an active hub

to repeat our signal on a cable and make it go further,

we can use a wireless range extender

to repeat our wireless signal

and give us additional range too.

Depending on the coverage area you have,

it's really going to determine the type of antenna

that you want to use inside your home or your small office.

You're probably using a standard fixed antenna

on your wireless access point.

But when you start designing things

for an enterprise network,

you're going to start choosing the right antenna

for the right job.

Now, there are different factors

that will help you determine the effectiveness

of your antenna,

including the distance you want to cover,

the pattern of the wireless coverage you need,

and the environment itself,

whether it's inside or outside.

If you want to avoid interference with other access points,

all of these things go into your decision making

when determining the right antenna to use.

The most commonly used antenna

is an omnidirectional antenna.

The way it works is it's either built in

or a fixed antenna on your wireless access point.

It's going to radiate power out equally

in every single direction.

And so if you're using an omnidirectional antenna,

it's usually best to place your access point right

in the center of your room.

If you go to a college classroom, for instance,

and you look up in the center of the classroom,

you may see a wireless antenna

that's omnidirectional, sitting on the ceiling,

providing full coverage to that entire classroom.

In your home,

if you have a Verizon or a Comcast

or another cable service provider,

and they give you one of those all-in-one devices

with the wireless router configuration,

these have an omnidirectional antenna

that go out in every single direction.

The next one we have is what's known

as a unidirectional antenna.

Now, uni means one.

So all the power is being focused out

in one particular direction.

And most common,

your unidirectional antenna is going to be something known

as a Yagi antenna.

That's spelled Y-A-G-I.

Now, I have one here displayed for you on the screen.

The most common use of a Yagi antenna

is when you want to put out power over a longer distance

and connect buildings to other buildings or to other sites.

We might put two wireless access points

on the top of a building, point them at each other,

and use a Yagi antenna that's pointed directly

at the other one to maintain that connection.

In this example here, I have two buildings

and you'll see strong blue radio waves going

between the two.

You'll notice that there's not much waves going out

the other side from the other direction.

That's because of the Yagi,

we're really focusing

and putting all that power out a single direction

because it is a unidirectional antenna.

Now, where else might you find directional antennas?

Well, if I'm trying to provide

a wireless network inside a building

and on the inside of the building

I want to use unidirectional antennas

to shape the direction of where I want that power to go.

This way, instead of going out equally in all directions,

I can focus it in a particular direction

and ensure that I'm not having my wireless signal go out

and bleed into the parking lot,

and that way it's not going out as a security risk.

Going back to the heat map we had in the previous lesson,

you can see where this can become really important.

Now, for the exam,

you may get something like a picture of a floor plan

and be asked to pick which antennas

should go in which places.

And so maybe you're going to put in three or five

or 10 different antennas.

And you might have to decide if you're going to put

a left directional antenna in on a right wall.

So you're keeping the signal inside the building.

Or, a right directional antenna on the left wall.

Again, keeping it inside the building.

If you're in the center, you want an omnidirectional.

If you want to connect one building to another,

you might use something like a Yagi antenna on the roof

to point that to another building

and keep it directional as well.

These are the kind of things you need to think about

as you're picking your antennas for the case

that you're doing

and whatever scenario they give you.

So, in this lesson, I wanted to show you

what some of these antennas look like

with more of a hands-on approach.

So, let's go ahead and start with what's called

an omnidirectional antenna, and this is what you have

in most of your wireless access points

and most of your wireless devices.

So, if I take, for instance, this old cellphone.

This old cell phone has a Wi-Fi connection

inside of it, built in.

It actually is an Android cellphone

and it has the ability to either receive a wireless signal

through Wi-Fi or put one out as a hotspot

and then allow other devices to connect through wifi to it

and then go out through its cellular connection

to get access to the Internet.

Now, you'll notice, when I was talking about this cellphone,

I mentioned it's omnidirectional.

And that makes sense for a cellphone

because as you're walking around,

you don't know which direction

the signal's going to be coming from.

So, instead, it's going to send and receive data

both up and down, left and right,

forward and back, in every single direction,

with equal power to be able to connect

to the local wireless access point

or the local cellular tower,

depending on which frequencies we're using.

Now, this is the same thing that happens

with your wireless access points, too.

So, for instance, if I take this old

wireless access point from Netgear,

you'll see this is actually a combination device

of a router, a switch, as well as a wireless access point.

There's no external antenna.

Instead, they're using an internal omnidirectional antenna

just like that cellphone did.

And so, in every single direction,

we're going to be sending data out

to be able to get data out equally in all directions.

So, if I want to make sure that this doesn't bleed over,

if I'm in a townhouse or an apartment, for instance,

I'd want to put it closer to the center of my apartment,

because if I put it on one of the walls,

it's going to go out in every direction,

including through the wall and into my neighbor's apartment.

And so, you might want to consider

that from a security perspective.

Now, some of the more expensive wireless devices

are going to give you the ability to change out your antenna.

So, for example, we talked earlier

about this combination device that I got from Verizon.

And inside this one, we did have the ability

to connect a different antenna.

So, normally, it's going to come with an antenna like this,

which is a standard little whip antenna

and this is considered an omnidirectional antenna.

So, as I connect that on there,

I'm going to be able to send data out

in every direction, all 360 degrees.

Now, this is a rather small antenna,

so it's not going to have as much power.

Maybe I wanted to get my signal to go out further.

Well, I can actually change that.

And I can take that antenna off

and I can put on a bigger antenna.

And with the bigger antenna, I'm actually going to be able

to send data out a little bit farther than I could before,

because the longer the antenna,

the more propagation you're going to get from it.

Now, also, when I'm doing wireless attacks

and wireless hacking and pentests,

I actually have a wireless card

that I use with my laptop and that has the ability

for me to change the antenna, as well.

And so, I would take this wireless card

and I would screw on whichever antenna I want.

So, if I want more distance or more power,

I can go ahead and use an omnidirectional antenna

like this, screw it on, connect this through USB

back to my laptop, and now, I have this antenna

radiating out in every direction.

Now, I've spent a lot of time talking

about omnidirectional antennas,

but what do you do if you want to

make it go in a single direction?

For example, when I'm doing wireless pentesting,

often, omnidirectional is not the best way to go

because when you're putting power out in all directions,

you're limited in how far you can go.

But if I can focus my power in just one direction,

that's called unidirectional, I can actually focus

all the power out the left side of the antenna

or the right side of the antenna.

And that way, I can push all of the power one way

and no signal goes out the other.

So again, going back to the apartment example,

if I'm up against the right wall of the building

and I have a directional antenna pushing

all the power out left, it's going to go into my apartment

and not into my neighbor's, because we have that right wall.

That's using a unidirectional antenna.

And we have unidirectional left,

unidirectional right, and things like that,

so we can choose which direction we're going to be using.

Now, the other thing when we're dealing with antennas

you have to think about is what are some

of the other types of antennas that are out there?

Besides the standard unidirectional and omnidirectional,

uni meaning one, omni meaning all,

we also have things known as parabolic.

Now, parabolic are a special type of unidirectional.

Parabolic is going to give it a different curvature

to the way the signal's going to go out,

and it's most often used with microwave signals,

as well as satellite TV signals,

as you could see here on this particular antenna.

Now, this is a DIRECTV antenna

on one of my neighbor's houses

that I drove by and took a picture of for you.

And you can see that curvature

of the dish which is going to focus

the energy up and towards the satellite

and not out in every other direction.

Finally, I want you to consider this other antenna here.

This one is actually in the UHF band,

which is a frequency band that we use,

and it used to be used a lot for TV before we had cable.

You'd have UHF and VHF.

Now, with this antenna, you can also see

that it is a very directional antenna.

You could see how it's pointing

in one direction, almost like an arrow.

That's going to allow it to get a further reach to that signal,

to that TV transmitter that's sending it out.

Now, do we use these anymore?

Well, sometimes.

These actually can be used to point

and push a wireless signal over a longer distance.

So, if you're in a business park or a campus setting,

you might see some of these antennas on top of buildings

pointing from one building to the other,

using this unidirectional antenna.

And in this case, this is actually known as a Yagi antenna,

Y-A-G-I, and it allows them to have a very directional,

focused beam going from one building to another.

So, if you hear the term Yagi,

that is going to be something that is a directional antenna,

unidirectional antenna, going one way.

Now, if you hear about parabolic,

I want you to think about that satellite TV,

that curved dish that's pointing

that directional back towards the satellite.

And if you think about omnidirectional,

I want you to think about these embedded devices.

Things like your wireless access point

or things like your cellphone

or things like your wireless card

with a long antenna like this one.

But this is just the idea.

There's different types of antennas

used for different situations,

and it all depends on what you're going to do.

Now, for the exam, you want to be able to know

when you should use an omnidirectional antenna

or when you should use a directional antenna

or when you should use something that attaches

to the side of a building, like a patch antenna,

which is a small, circular dish

that is able to go on one side of the building to another,

and they can point at each other in a directional manner.

These are different types of antennas

that you may come across when dealing

with wireless networks and they're important

to understand before you take the exam.

Wireless frequencies.

We've talked about antennas

and we've talked about the basics of wireless.

Now it's time for us to dig a little bit deeper

into the specific frequencies that are being used

in this wireless spectrum.

First, I want to talk about spread

spectrum wireless transmission.

There are three main ways that we can do this.

The first is DSSS or direct sequence spread spectrum,

the next is FHSS or frequency hopping spread spectrum

and the third is OFDM

or orthogonal frequency division multiplexing.

Now in today's networks,

we don't rely as much on frequency hopping,

instead, we like to use direct sequence

or orthogonal frequency division.

Now we're going to talk about this

as we go through each of the next parts of this lesson.

First, we have DSSS or direct sequence spread spectrum.

This is going to modulate your data

over the entire range of frequencies,

using a series of signals, which are called chips.

Now these chips are more susceptible

to electrical interference and environmental interference,

and that's going to cause us to have slower bandwidth.

For this reason, we don't use it very often.

Also, it's going to use the entire frequency of the spectrum

to transmit signal.

This is very self optimal for us.

So for example, if I'm using channel one

or channel six or channel 11,

you can see here on the screen that I have large portions

of that frequency band being used.

Now to have no overlapping channels

and prevent interference,

I have to use channels one, six and 11,

but that means I'm giving up all the other channels,

two, three, four, five, seven, eight, nine, and 10.

You can see this is a ton of wasted space here

because we're using DSSS.

On the other hand, FHSS or frequency hopping spread spectrum

is going to allow devices to hop

between predetermined frequencies.

Now, this makes it harder to guess

where the frequency actually is,

depending on the algorithms being used by your protocol.

Now, frequency hopping is used as a security measure

in some networks,

but in most commercial grade wireless networks,

we're not going to be using it,

because it slows down our ability to use all the bandwidth

and reduces the amount of spectrum you have available

to use for bandwidth.

And so this is going to start slowing down your network,

although it does increase security.

So using it is a trade off, if you decide to use it.

Our next and our most common one that we use nowadays,

is known as OFDM,

orthogonal frequency division multiplexing.

Now, OFDM is going to use a slow modulation rate

with simultaneous transmissions

over 52 different data streams.

By doing this with these small chunks,

we're able to actually take a larger piece of the spectrum

and give us more bandwidth.

Now, this gives us higher data rates

while at the same time resisting interference,

because these data streams are small little chunks.

Now, if we compare OFDM,

that's used by wireless G and wireless N

and we can see how these differ.

When we use it with wireless G,

we're going to be using it with a 22 megahertz spectrum,

and these chunks are going to take place

on channels one, six, and 11.

Now, if I move into wireless N,

in the 5 GHz spectrum,

we're now going to have a 40 megahertz chunk.

That's going to give us the ability and additional bandwidth

to increase our speeds in wireless N,

and following protocols like wireless AC and wireless AX.

Now, before we go further, I do want to point out

that for the exam, you do not need to go in-depth in DSSS,

frequency hopping, orthogonal division.

Instead, you really just need to know these three terms,

and when you see them, they're referring to something

in the wireless networking world,

if you know that you'll be able to pick out

the right answer on test day.

Just recognizing those three terms are relating

to wireless networking, is really as in-depth

as you need for this particular exam.

Next, let's talk about frequencies and channels.

Now we've already touched a little bit on this,

as I started talking about 2.4 GHz and 5 GHz.

These are two different spectrums

that are used by wireless networks today.

The 2.4 GHz band, actually isn't 2.4 GHz,

it's 2.4 and 2.5 GHz,

but for the exam and anything else you see in real life,

people are just going to say 2.4 GHz,

and that's sufficient.

Now the same thing holds shoe with 5 GHz,

technically it's 5.75 to 5.875 GHz,

but everyone just calls it 5 GHz.

And for the exam, that's what they'll call it as well.

So each band here between 2.5 GHz and 5 GHz

has specific frequencies and channels

that are going to be used,

and this helps us to avoid overlapping with other signals

and causing interference.

Now, when I talk about a channel,

I'm really talking about something that's anomalous

to a physical medium.

Now, when we think about a channel,

it's essentially how we're going to transmit information

over our wireless networks.

Think about it like a virtual pipe.

It's very much like the physical cables

we use in our wired networks,

but instead of a physical copper or fiber cable,

we're using a portion of the wireless frequency

that exists to create these channels, and send our data

over these virtual pipes, over the airwaves.

Now, depending on which frequency band you're using,

you're going to have more or less channels available.

When we deal with the 2.4 GHz spectrum,

there are 11 channels or 14 channels.

Now, the reason there's a difference

is because of regulation,

depending on where you are in the world,

you'll never have access to 11 channels or 14 channels.

All wireless frequencies are regulated by the country

that you're operating in.

So if you live in the United States, you can only use

11 channels within the 2.4 GHz spectrum.

This goes from 2401 megahertz, up to 2473 megahertz.

Now, if you're operating in the rest of the world,

except Japan, you can operate from 2401 megahertz,

just like the United States, up to 2483 megahertz.

If you're operating in Japan,

you can go all the way up to 2495 megahertz.

So this means in the U.S. we only have 11 channels,

the rest of the world gets 13 channels,

and Japan has 14 channels.

Now, each of these channels is only around 22 megahertz wide

within the 2.4 GHz spectrum.

This is going to limit the amount of data

that we can send at any given time.

The other problem we have these channels,

is that they actually overlap a lot

because we only have 72 megahertz of total frequency

inside the 2.4 GHz spectrum

that's been allocated to us by the FCC

and other regulatory authorities

within our 802.11 wireless standards.

So if you're dealing with 2.4 GHz for instance,

there are going to be three channels

that you have to memorize

and use these three channels to prevent interference.

These are channels one, six, and 11.

Those three channels are truly important

because they are far enough apart from each other

to prevent any kind of interference

by giving you 22 megahertz for each of those three channels

and still fitting within the 72 megahertz

total spectrum provided.

So if you're ever asked about

how to prevent wireless interference,

and somebody asks you what channels you should use,

the answer is always going to be one, six and 11,

if we're talking about using wireless B, wireless G

or wireless N within the 2.4 GHz spectrum.

Because of this limitation, newer wireless networks

are going to operate in the 5 GHz spectrum instead.

In the 5 GHz spectrums,

regulators have given us from 5.725 GHz

all the way up to 5.875 GHz.

This allows us to run our wireless networks

within that range.

Now, if we keep with the 20 megahertz wide channels

that we're using with 2.4 GHz,

we are now going to have 24 non-overlapping channels,

which is a huge improvement

over the older 2.4 GHz networks,

which only had the three non-overlapping channels

of one, six and 11.

Now, inside of our 5 GHz networks,

we can also make wider channels

than just 20 megahertz though.

Starting with wireless N networks,

there's an option to perform,

what's known as channel bonding,

and this was increased in wireless AC

to allow for 80 megahertz channels

and 160 megahertz channels too.

So, what is channel bonding?

Well, bonding a channel allows you to create

a wider channel by merging neighboring channels into one.

Think about it as if we have these virtual pipes

and we put them all together.

That's going to allow us to push more data through

at the same time.

So, instead of only taking up 120 megahertz area

for a single channel,

we can now take two 20 megahertz channels

to give us a 40 megahertz bonded channel,

or I can combine eight of these channels

and get 160 megahertz channel.

By having this wider channel,

I can push more data across the network at one time,

leading to increased speeds and additional bandwidth.

Now, the only challenge with channel bonding,

is that now increases the probability

that you can experience interference,

because you're now reducing the number

of non-overlapping channels,

because you've taken up more of the spectrum

by combining these channels together.

Remember with 5 GHz networks,

we have 24 non-overlapping channels of 20 megahertz each,

but if I created a bonded channel of 160 megahertz,

I just took up the equivalent of eight

of those 24 non-overlapping channels.

This could lead other wireless network devices

near my access point,

to start causing interference with my network.

Now, for the exam, you don't need to memorize

all the different frequencies for the different channels,

instead, you should be aware of the standard channel size

being 20 megahertz for both 2.4 GHz

and 5 GHz networks.

But if you use channel bonding

with the 5 GHz network, you can make them larger.

You can make them two times,

four times or eight times as wide.

Now, when you do that,

you can reach higher network speeds,

but you also risk more interference too.

So it is a balancing act between these.

Now up to this point,

I've mentioned a few wireless standards like B and G,

N and AC.

Next, I'm going to provide you

with a nice little summary chart,

that's going to cover all the wireless networking standards

that you need to memorize for the exam.

This is one that I would print out and memorize.

You need to know the standard and you need to know the band,

and you need to know the maximum bandwidth.

These three pieces of information are very important.

Now, when we start out with wireless networks

all the way back in the early 1990s,

we only had the 802.11 standard.

This standard though, was not commercially viable,

and it was essentially a big proof of concept.

It didn't really make it into the marketplace.

It operated in the 2.4 GHz spectrum,

but it only operated

at about one to two megabits per second.

Now, for your chart,

I wouldn't even bother writing that one down.

Instead, you need to know about A, B, G, N, AC,

and AIX for our exam.

Those six Wi-Fi types are the ones you need to memorize

for the exam,

with those three pieces of critical information

to make sure you're successful on the exam

for wireless networking questions.

Let's talk about each one now.

First, let's talk about wireless A, or 802.11a.

This operate in the 5 GHz spectrum,

which was a very expensive radio to build a manufacturer

at that time,

but it did give us a good amount of speed

because it operated at 54 megabits per second.

This was really good in the late nineties,

but again, unfortunately it costs a lot of money

because of that high cost, only business users

really ended up using it,

and it wasn't really that commercially viable

in the mainstream market.

Now, since it wasn't getting as much traction

in the commercial markets,

they decided to make something cheaper and easier.

So the manufacturers decided to create wireless B,

which operates in the 2.4 GHz spectrum.

Now, this frequency range is commonly used

by a lot of other household devices,

things like security cameras, walkie-talkies,

baby monitors, microwaves, and more.

Now, this made the radios and the 802.11b wireless devices

very cheap and easy to get

and it led to widespread adoption of Wi-Fi throughout homes,

businesses, and schools bringing us to where we are today.

Now using this cheaper chip set

and the way the frequencies work,

actually slowed down our networks.

So we went from 54 megabits per second,

down to 11 megabits per second,

which today sounds extremely slow.

But again, we're talking about the late 1990s here,

and we weren't doing a lot of streaming video,

and so 11 megabits per second was actually fast enough

for most home users.

Now over time though, networks got faster

and we wanted more speed.

And so wireless G came out as a replacement for wireless B.

Now wireless 802.11g is also in the 2.4 GHz spectrum,

but it operates at 54 megabits per second.

Now, eventually we wanted to go even faster than this,

so engineers kept working on new solutions

and new ways to manipulate the frequencies.

And eventually they came up with wireless N,

which is also called Wi-Fi 4,

since it was the fourth generation of Wi-Fi.

Now 802.11n really wanted to increase speed.

So moved back to the 5 GHz spectrum again,

and this allowed to get up to speeds

of 300 to 600 megabits per second.

This allowed for really fast networks,

but the big problem

is that this newer 5 GHz spectrum

wasn't compatible with all the existing devices

are out there, because they were wireless B and G,

and they operate at 2.4 GHz.

So people were resistant to buying wireless N at first.

Now to overcome this manufacturer started

making hybrid devices that were market under the name

wireless N, and these types of devices

had a wireless access point with two sets of radios in them.

One was for the 2.4 GHz spectrum,

and one for the 5 GHz spectrum.

This way, if you had a mixture devices that were 802.11b,

and G, and N, you could connect

to the slower 2.4 GHz spectrum,

and it would support wireless B speeds, wireless G speeds,

or newer wireless N speeds

that went up to about 150 megabits per second.

Now, if someone connected

to the more modern wireless N radios

using the 5 GHz spectrum, they could actually

reach speeds up to 600 megabits per second,

by using a technology known as MIMO.

MIMO stands for multiple input and multiple output,

which means that the access point

could use multiple antennas to send and receive data,

instead of putting it all through a single antenna,

essentially your data was going to be split

across multiple antennas,

and it was received on the other end,

it was multiplex back into a single data stream

for processing.

This is why you can see wireless and access points

that have one, two, three, or even five antennas,

because the more intense you had,

the more data transfer they could support simultaneously.

Next, we have wireless AC, which is also called Wi-Fi 5,

or 802 11 AC.

This was the fifth generation of Wi-Fi.

Now wireless AC operates exclusively

in the 5 GHz spectrum,

and technically it does not provide

any kind of backward compatibility.

These 802.11ac networks can operate

at speeds up to three gigabits per second or more.

These networks are really fast in theory.

Now to achieve these higher speeds,

802.11ac networks, uses the technology known as MU-MIMO,

which has multiple user, multiple input, multiple output.

It's a newer variation of the MIMO technology

that was first developed back with 802.11n networks.

Now MU-MIMO is a multipath wireless communication technology

that allows multiple users to access the wireless network

and access point at the same time.

This is different than a regular MIMO,

where a single user supported at one time.

And the access point switches between users

to share the bandwidth across all the users

who are requesting services.

So if you only have one person requesting services,

they get a really fast network, but if you have, or three,

it starts slowing down because it just share the bandwidth.

Essentially with MIMO,

the wireless network acts more like a hub,

but with MU-MIMO, it begins to act more like a switch

and helps avoid collisions and congestion.

Now, when it comes to wireless AC,

some of the original and older AC devices actually still use

the older MIMO technology.

Whereas the newer wireless AC devices, will use the MU-MIMO

for faster speeds.

Now, this brings us to the latest generation

of wireless networks, 802.11ax.

Wireless AX is known as Wi-Fi 6,

because it's the sixth generation of wireless networks.

This was introduced in 2021, and it can be used

in the 2.4 GHz and 5 GHz spectrum

under the marketing term, Wi-Fi 6

or in the newer and faster six GHz spectrum

under the marketing term, Wi-Fi 6E

or high efficiency Wi-Fi.

Now these Wi-Fi 6 and Wi-Fi 6E networks,

is 802.11ax networks,

can reach speeds up to 9.6 gigabits per second,

using MU-MIMO technology.

Also, because these access points have both the 2.4 GHz

and 5 GHz radios inside them,

they are fully backwards compatible with all devices,

including wireless A, B, G, N and AC.

All right, for the exam, I want you to remember

there are different wireless networks out there.

These include A, B, G, N, AC and AX.

You also need to remember that if it's a B, G,

N or AX network,

it's going to support 2.4 GHz as a spectrum.

If it's A, N, AC or AX,

it supports 5 GHz as a spectrum.

You also need to remember the relative speeds

of these different wireless devices,

going from 11 megabits per second for wireless B,

all the way up to the gigabits per second use

in AC and AX networks.

This is important for the exam, because on test day,

you may get questions about frequencies,

things like which of these frequencies

do not support 5 GHz?

And the answer would have to be either B or G,

for wireless B and wireless G.

Now, you may get a question asking you to select

which wireless standard doesn't support 2.4 GHz.

And in this case,

you need to select wireless A or wireless AC.

If they wanted to make it more difficult for you,

they can ask the question

as more of a troubleshooting scenario, for example,

you're working as a network technician on an older laptop,

and it's failing to connect to your wireless AC network,

you check the laptop and see

that it has a wireless B network card.

What is the problem?

Then you're going to find the answer that has something

to do with the fact that there's a frequency mismatch,

because wireless AC supports 5 GHz

and wireless B supports 2.4 GHz.

And therefore you can't connect to the network.

Now, one more thing to keep in mind as you're studying,

is that marketers sometimes mislabel things

to make it easier for our consumers.

But on test day,

you have to go by the official standards.

A great example of this is wireless AC,

the 802.11ac standard.

It only specifies operation

in the 5 GHz frequency band.

But if you go to the store

and you find a wireless AC access point,

the box will tell you, it supports both 5 GHz

and 2.4 GHz.

This is a lie, and you will get in trouble on the exam,

if you pick this answer, because you think it's dual band,

and it's not the truth is wireless AC,

only operates in the 5 GHz spectrum.

When you're buying that wireless AC access point

at the store, and it says it supports both frequencies,

it's actually a wireless access point with two radios in it.

One radio is 5 GHz for wireless AC

at speeds up to about 1300 megabits per second.

The other one is a 2.4 GHz radio for wireless N,

at speeds of up to 600 megabits per second,

with a MIMO antenna configuration.

Now, while in real life, your users really don't care,

and they just say, hey, I have a wireless AC access point,

and they think it supports both 5 GHz and 2.4 GHz,

on the exam, you will get the question wrong,

if you select 2.4 GHz for wireless AC.

Remember wireless AC only supports 5 GHz

for its operations.

The only dual band standards we have are wireless N

and wireless AX.

Both of those support, both 2.4 GHz

and 5 GHz frequency bands per the 802.11 standards.

Now, let's talk about radio frequency interference,

or RFI for a minute here.

Radio frequency interference is caused

when there are similar frequencies

to wireless networks in your area.

For example, I mentioned earlier that one of the reasons

we went to 2.4 GHz for Wi-Fi B,

was the fact that there was other videos out there

that already used it.

Things like baby monitors and cordless phones,

and microwave ovens and other security devices.

Now, this means that 2.4 GHz as a spectrum

is fairly crowded.

This is what made the radios cheap,

but it made it very difficult for us

because it causes a lot of interference.

Over time as more and more devices moved

into the 5 GHz spectrum,

there's also more interference in that area too.

All of these other electronics can cause interference

with your wireless networks,

so you have to think about these things as you're developing

your networks and troubleshooting your networks.

For example, if you have a 2.4 GHz

wireless G network in use, and the access point happens

to be sitting in the break room at the office,

and every time somebody turns on the microwave

to reheat their burrito, the network drops,

this is probably because the 2.4 GHz frequency

is being interfered with,

by those microwaves that are operating

in that same frequency band.

In addition to all this frequency interference,

you might also see things like physical interference.

This is where physical things

can block your wireless signals.

For instance, I live in Puerto Rico

and the walls in my house are solid concrete.

I also have a refrigerator inside my kitchen,

I have kitchen cabinets and those block the signal,

all these things can cause signal strength issues for you.

If your signals are too weak,

and it can't make it around a corner or through a wall,

that signal is going to get blocked,

or it suffers what's known as a tenuation.

All of these things can lead to interference,

which will slow down your ability for your network

to operate at top speed.

As your signal decreases in strength

or interference increases,

we get a worse signal-to-noise ratio.

This is going to cause additional retransmissions

because most of the time we're sending things over TCP,

when TCP retransmit, this creates additional network baggage

that's being taken up and bandwidth is being used

for all these retransmissions.

And this slows down the network even more.

You want to make sure you have good signal

throughout your entire structure

to increase the efficiency of your network.

To do this, you would do what's called a site survey

where you check the signal strength in different areas

and make sure you have the right antennas

and the right repeaters throughout the building.

Finally, let's talk about how we actually send data

over one of these wireless networks.

With Ethernet, we talked about the fact

that we use CSMA/CD, which was

carrier sense multiple access/ collision detection.

With wireless networks, we're going to use something

known as CSMA/CA,

which has carrier sense multiple access/collision avoidance.

See here we've changed collision detection

to collision avoidance, once we went to the wireless domain.

Both CD and CA are going to start out the exact same way,

in both of these network types,

we're going to listen for transmissions.

If we think the line is clear in the case

of CD using Ethernet or CA we're using wireless,

and the frequency has to be clear,

we can then send a message.

This is the carrier sense multiple access part

of this stuff.

Now, in the case of Ethernet,

this is where we stopped doing anything.

We're just going to do carrier sense multiple access

collision detection.

We're going to send our message and see if it crashes.

This way, if there's a collision,

we're going to just retransmit it.

Now with wireless though,

we want to try and prevent collisions ahead of time,

because we said, retransmissions eat up valuable bandwidth.

This is where collision avoidance comes in.

As the device gets ready to transmit,

it's going to listen to the frequency

and make sure it's clear,

and then it's going to send out a packet

that's known as an RTS, which stands for Request To Send.

The intended recipient usually the wireless access point

on the network, will then acknowledge that Request To Send

by sending a CTS packet, which stands for Clear To Send.

Now, once my device sees the CTS packet,

it's going to go ahead and send my data, because I was told,

the whole frequency is clear,

and it's ready for me to send something.

Now, if we don't receive this CTS signal,

this Clear To Send acknowledgement,

then we're not going to start sending.

Instead, I'm going to choose a random backoff timer,

I'm going to wait for something like 30 milliseconds,

and then I'll do another RTS or Request To Send.

Now until I received that Clear To Send packet,

I am not going to go and send my message,

because I don't want to cause a collision.

Remember every collision causes a retransmission,

retransmissions take up valuable bandwidth,

and that starts taking up additional resources

and it becomes a negative spiral

for our network's performance.

So remember collision detection is used in wired networks,

collision avoidance is used in wireless networks,

and we won't send until we see that Clear To Send signal

in response to are Ready To Send packet.

In this lesson,

we're going to talk all about how to secure

your wireless networks

from some of the threats against them.

Now, wireless networks offer us a lot of convenience,

but it also brings a ton of security risks

because unlike a wired network,

as long as I'm within the footprint of that wireless signal,

I can connect to it with my smartphone,

my tablet, or my laptop.

To protect your network,

you really need to make sure you know

what your devices are connecting to,

and once they're connected,

you want to make sure that the data being sent

is going to be encrypted.

Now, the first thing we want to do is make sure

that whatever we're transmitting is being done privately

to increase the security of our networks.

One of the ways we do this is what's called

a Pre-Shared Key.

Now, a Pre-Shared Key is where both end points,

both your access point

and your client on your laptop or smartphone,

have the same encryption key.

If I use a password on one side

and the same password on the other and they match,

that is using the same Pre-Shared Key

to create that encryption tunnel.

Now, there are a couple of problems

when you use a Pre-Shared Key, though.

First, scalability becomes a big problem for us.

Let's say I have an office where I have 50 different users

and they're all connected to the wireless network.

And all of them are using that same Pre-Shared Key.

But, let's say tomorrow I go into work

and I fire one of the employees.

Now, that employee knows the Pre-Shared Key.

So, guess what we have to do?

We have to change the Pre-Shared Key.

And because I have to change that Pre-Shared Key,

all 50 of the other employees now need to be told

what that new key is, and so we can all change it.

It's like changing the key to your front door of your house.

If you have 10 family members,

you now have to make 10 copies of that key.

Since all of your clients are using the same password

and that same key,

it makes it really difficult for us to change

and do proper key management.

That's one of the big reasons

why we don't use Pre-Shared Keys in large environments.

But if you're in a small office

or a home office environment like your house,

or a small office of 10 employees or less,

you may go ahead and use a Pre-Shared Key,

because it's really easy to configure networks that way,

because you only have a couple of devices.

Now, when we look at wireless security,

there are three main methods that we can use for doing this.

The first is WEP, and then we have WPA and WPA2.

When we deal with WEP,

we're talking about Wired Equivalent Privacy.

This was the original wireless security that was invented

all the way back

with the first version of Wi-Fi with 802.11.

Now it claimed that it was as secure as wired networks,

hence the name Wired Equivalent Privacy,

but the truth is, it is not secure,

and these days you should never ever be using WEP,

because it is a very insecure protocol.

Now, the way WEP works is that it uses a Pre-Shared Key.

Everyone has the same key, and it's a static 40-bit key,

which is very small and easy to brute force or guess

using a strong computer.

Over time, to make WEP more secure,

they upgraded the key from 40 bits to 64 bits,

and then again to 128 bits,

and that solved the key length problem,

but it didn't solve a different problem

known as the Initialization Vector.

Now, the way WEP works

is it uses a 24-bit Initialization Vector,

which is a series of 24 ones and zeros,

and they are going to be called this Initialization Vector.

This is sent in clear text,

and if you capture enough of these Initialization Vectors,

you can actually crack the encryption key

and backwards guess the Pre-Shared Key

that you used for your password of WEP.

In fact, using Aircrack-ng,

you can do this in about two to three minutes

with most modern laptops.

Now, the next one we want to talk about is WPA.

WPA, or Wi-Fi Protected Access was the replacement for WEP

because of the weakness

with this 24-bit Initialization Vector.

To overcome this, they introduced something known as TKIP,

the Temporal Key Integrity Protocol.

Now, TKIP is replacing that 24-bit Initialization Vector

with a new vector that is 48 bits long.

This doubled the strength of it,

but that's still considered pretty weak

when it comes down to modern computing.

The other thing they did was they added a new encryption

type called RC4, or Rivest Cipher 4,

and it's pretty good, but again, by today's standards,

this is considered weak.

WPA also wanted to add some integrity to your devices,

and they did that by making sure nobody can conduct

a man in the middle attack and change the information.

To do that, they used a thing called the MIC,

the Message Integrity Check,

which is a form of hashing the data before it was sent,

and that way you could verify it wasn't modified

as it was in transit as it went through the network.

Now, WPA also saw that there was a flaw

with this Pre-Shared Key and being able to send out new keys

very quickly, so they added something

known as Enterprise Mode inside WPA.

With Enterprise Mode,

a user could actually authenticate before exchanging keys,

and they would then be able to create new keys temporarily

between the client and the access point.

This tried to solve that Pre-Shared Key scalability issue,

but at the end of the day,

WPA is still considered weak by today's standards

and is replaced with a more modern version known as WPA2,

or Wi-Fi Protected Access 2.

Now, WPA2 is the current standard,

and it was created as part of the 802.11i standard.

It was first implemented with wireless G,

and then in wireless N and wireless AAC.

It requires strong authentication

and stronger encryption and integrity checks.

The integrity checking is done through using CCMP.

Now, CCMP stands for the Countermode with Cipher

Blockchaining Message authentication code protocol,

which is a mouthful that you will not have to memorize

for the exam or what it means.

What you do need to remember is every time you see CCMP,

you should be thinking about this is part of WPA2 security.

The second thing they did was they replaced

that older encryption mechanism of RC4, the Rivest Cipher 4,

with the new one

known as Advanced Encryption System, or AES.

Now, AES uses 128-bit key, and some newer models

can actually use a 256-bit key or more.

This gives you additional security and confidentiality

of your data going over this wireless network.

At the time of this particular recording here in 2020,

AES has still not been broken,

and WPA2, the algorithm itself, has not been broken.

So it is a good thing to use

if you have a long, strong password.

Now, the only way that people are able to crack

these networks currently is by using password attacks.

And that means they're trying to guess the passwords

by guessing every possible option

using a brute force attack or a dictionary attack.

So if you want to protect your networks,

make sure you're using a good, long, strong password.

WPA2 also supports two different modes

depending on your network that you're going to be using it on.

If you're using it in a home or small office environment,

you're going to be using a Pre-Shared Key

where everybody has the same password.

This is known as Personal Mode.

The other way is by using it in a large environment

where you're using Enterprise Mode,

and that's where each and every user

gets a single username and password unique to them,

and they'll use a central authentication server

using native WPA2 or offloading that

to an 802.1x authentication server.

For the exam, I want you to remember four things

about wireless security.

If you remember the four things on this chart,

you're going to do great.

First, anytime you see the word open

in reference to a wireless network, that means no security,

no protection, no password.

If you hear WEP,

I want you to associate this with Initialization Vectors.

That's the flaw in WEP,

and that's what you're going to hear about on the test.

WEP is weak, WEP is bad, WEP uses Initialization Vectors.

If you see WPA,

I want you to think about TKIP and RC4,

because TKIP was what we used

to replace the Initialization Vectors

and RC4 was its form of encryption.

Again, WPA is considered weak. Don't use it.

Next, if you see WPA2,

you should be thinking about the acronyms of CCMP and AES.

CCMP is that integrity protocol,

and AES is the encryption mechanism we use.

This is your key to answering wireless questions

for security on exam day.

Now, when you're using WEP and WPA and WPA2,

there are many utilities out there

that can capture wireless packets,

run them through mathematical algorithms,

and determine the Pre-Shared Key.

One of the most popular tools for this

is known as Aircrack-ng,

and it comes by default inside Kali Linux,

which we use for Wi-Fi penetration testing.

We want to protect ourselves from this,

and the way we do this, in the enterprise,

is we're actually going to use something

like network authentication, using 802.1x,

and on a personal side,

we'll use long, strong passwords.

Now I know we mentioned 802.1x previously,

but again, you can use it in wired or wireless networks.

When you do, each wireless user

can do its own authentication

using their own username and password,

and passing it over that 802.1x protocol.

The supplicant passes it to the authenticator.

The authenticator passes it to the authentication server.

It checks your credentials.

And if they're valid,

it sends it back as a single key,

back to the authenticator,

and then we create the EAPOL tunnel

between the supplicant and the authenticator.

Now, what is this EAPOL key in this tunnel?

Well, that's part of the EAP,

or Extensible Authentication Protocol.

And this is the authentication

that's being performed under 802.1x.

There are three modes of this.

With EAP-FAST, which is your flexible authentication

via secure tunneling protocol.

EAP-MD5, and EAP-TLS, or Transport Layer Security.

For the exam, if you see EAP,

I want you to remember it's part of 802.1x,

and that is part of network authentication.

Next, let's talk a little bit about MAC Address Filtering.

We talked about this back in wired networks,

and it's used just the same in wireless networks.

We can configure our access points with an ACL,

and this will be able to look at those addresses

and permit or deny certain MAC addresses

from connecting to the network.

For instance, if my iPhone tries to connect to the network

and it's not authorized, or it's on the deny list,

it won't be able to make that handshake

and it won't be able to communicate.

Now, the problem with MAC Filtering still resides

with the fact that it's really easy

to change your MAC address and spoof it.

Knowledgeable users can change their MAC address

really quickly using freely available tools,

and it really does take about five seconds to do.

This will stop some people, but it is not foolproof,

and it's not going to stop everybody.

If you want to change your MAC address and you use tools

like MAC Address Changer for Windows, MacDaddyX for OSx

and MAC systems, or MAC Changer for Linux,

these are all really easy tools to use.

MAC addresses are not going to be a source

of great protection for you, but according to the exam,

it is a protection that you can use

to form a part of your defense in depth strategy.

So in the real world,

don't worry too much about MAC filtering, but for the exam,

they do consider it a good security measure.

Next, we have Network Access Control, or NAC.

Now, what is Network Access Control?

Well, this is going to permit or deny you access to the network

based on the characteristics of that device,

instead of checking your user credentials.

Now, that sounds kind of complicated. What does that mean?

Well, I like to think about this

like passport control at the airport.

When I get off the plane and I go into a holding area,

we get into a line and we see the passport agent.

We show them our passport.

They look at it, they check our passport and our visa,

and they see if we're going to be allowed access

into their country.

Well, this is the same thing with Network Access Control.

Now, when I put a device on the network,

it's put into a quarantine area.

Then, there's a scan that's run on it.

And it checks its operating system,

its current patch level, its baseline,

and its antivirus version to make sure it's all up to date.

If all those things check out fine,

then it moves it logically onto the network

and allows it to connect.

This is a way to check your devices

and ensure they're safe and secure

before you add them into your network.

The next thing we need to talk about

with wireless security is a Captive Portal.

Captive Portals are going to be found

all over the place these days.

If you're at the airport or the coffee shop,

or a hotel and you go to log into the Wi-Fi,

you're usually greeted by a webpage that looks like this.

Now either you have to hit accept and continue

to be able to accept those terms and conditions,

entering your email address,

or some other thing like that to join the network,

or in the case of a hotel,

they might ask for your room number

so they can charge you for it.

All of these things happen at the Captive Portal.

Now, for instance, here,

you get this webpage and it's going to ask you

for those credentials or authentication

before it takes you onto the network and lets you

get access to the network.

Again, they're putting in this quarantine area

where you don't have access to the internet

until you make it past that.

The next concept with security we have is Geofencing.

Now, Geofencing uses GPS and RFID

to define real world boundaries for your devices.

These barriers can be active or passive

depending on how you set them up.

For instance, you might have a cell phone,

and then when it goes outside a certain range,

it sends a text message back to me, and that says,

hey, I'm outside the zone.

I've left the area, right?

And that'd be a bad thing.

Or you might have a passive one

where it just logs that information

so I can check it later.

This depends on if you want an active or a passive barrier.

Now, some of these active barriers

can actually be used as part of your authentication.

This is one of those things that for instance,

if I was in a location, say a Starbucks,

and they use Geofencing,

and I try to connect to their Wi-Fi,

it's going to verify that I'm actually inside their store

and not sitting out in my car in the parking lot.

That way they know that I'm in the store

and I might be buying a coffee,

and they use Geofencing in that mechanism.

Now, the other way you can do this

is your device can actually send alerts

if the device leaves the area and this way,

your authentication can be used to determine access

based on your location.

And that can be done based on city, state, building,

or even country.

For example, if you offer access to people

to use your network, and then somebody is connecting

from Russia, even though you're sitting in Washington, DC,

that's a problem, right?

You can block that based on the GPS address

of where they're sitting in Russia,

because they don't have a need to be using

your local network of your coffee shop

if you're located in DC and they're sitting in Russia.

We can do this by using geo-blocks based on their location.

Next, we have disabling your SSID broadcast,

which is considered a minor security help,

as well, to protect your networks.

Now, according to the exam, just like MAC Filtering,

they say, this is a good thing to do.

In the real world though,

it doesn't take very long to find a hidden SSID.

Now what exactly is an SSID?

Well, it stands for the Service Set Identifier,

and it's what your wireless network is actually called.

For example, if you go to Starbucks,

they have one called Starbucks Guest.

Or if you go to my house, I have one called Dion.

And that way you can see that service set goes out

and says, hey, Dion is here.

Should I connect to it?

And if you search for a network,

you see all the list of names that are around you, right?

Well, if you turn off the broadcast

of the Service Set ID,

it's not going to broadcast that out,

and it won't show up in your available networks.

This way, the user has to manually type in the name

to connect to your network.

So they have to actually know it's there.

Now the problem with this is that using wireless

penetration techniques, it's really easy to find these

and you'll still be able to connect to them.

If all you're doing is disabling your broadcast,

it's not very secure,

but if you do this in combination with MAC Filtering

and having a good, long, strong password,

you're starting to layer the security

and give you a better benefit.

Now, the thing we have is something bad,

and it's called a Rogue Access Point.

What is a Rogue Access Point?

Well, it's when a malicious user sets up an access point

to alert legitimate users to connect to it

and they can then become a man in the middle

and steal that data.

So, in this case, I have this blue laptop,

which is somebody at the coffee shop

who wants to be able to connect to the Starbucks network.

Now, I'm a bad guy and I've set up

this Rogue Access Point called Starbucks.

It's actually putting out more power

than the official Starbucks access point.

When their laptop tries to look for Starbucks and connect,

it's going to actually connect to me,

and then all their traffic

is going to go through my access point,

and then through my laptop before going out to the internet,

and this allows me to capture all their data,

their usernames, their passwords, and everything else.

This is why you need to be careful

when you're connecting to a public Wi-Fi.

Because you don't know if you're connecting

to the real Starbucks network

or the real print area network,

or the real McDonald's network or the real hotel network.

You could actually be connecting to a malicious user.

And that would be an unsecured network

where they can see what you're doing.

Now, hackers love unsecured wireless networks

because it's a great platform to launch attacks from.

And this may be things like coffee shops or hotels,

or even your home network.

There are two techniques that hackers use,

although most of us are now turning this

into a digital thing, as opposed to a physical thing.

In the old days,

people used to drive around to perform reconnaissance,

and it was called War Driving.

Now, I might have my partner drive the car

and go around the neighborhood while I scan

for any available networks that don't have a password,

and I mark down their location,

so I know where I can run my attacks from.

Now, in addition to that,

some people would do what's called War Chalking.

And so outside of the building

or outside on a telephone pole,

I might write some chalk that shows some network symbols

to tell them about this network I found.

So if there was a network that had a password

and I cracked that password, I could put that there as well.

There's some examples of those symbols here

on the screen for you to see.

Now, you don't have to memorize these symbols for the exam,

but understand the concept of what War Driving is

and War Chalking.

War Chalking is when somebody is notating the networks

you found when you were driving around

looking for networks that were open.

This is covered by your exam objectives,

so you should be able to answer questions on them

if you get them come test day.

Again, this is something hackers like to do

to tell their friends about all the networks they found,

and they can then use those as part of attacks

that they do later on as part of other measures.

In this video, I want to show you how

to set up a wireless router using the proper settings.

That means, we're going to be doing things like

MAC filtering, setting the broadcast to disabled,

and putting in a WPA2.

So, as we go through, I'm going to use this

Wireless-N wireless router.

This is a standard wireless router you might find

at Best Buy or Office Depot or some place like that

and it's probably what you have

something like this at home.

This is a standard model that's going to have

a wireless access point, a router,

and a switch built in.

So, as you can see, I have four different ports

plus the WAN connection which will connect

to my cable modem or my fiber modem.

Now, what I'm going to do is switch over

into the display and you'll be able

to see my computer as we go through

and configure this device.

So, I'm on my desktop computer and I've opened

up my network preferences.

This shows me that I'm currently connected

over ethernet directly to that wireless access point

because it has those four switch ports,

I'm plugged into port number one.

I received a DHCP IP address,

as you can see here, 192.168.1.2

and the router is 192.168.1.1,

so for me to be able to configure this

wireless access point, I'm going to go

and type in that IP address,

that router IP address, into a web browser

because most of these home access devices

are going to allow you to have a web-based configuration.

So, here I go 192.168.1.1 and it brings up

a Netgear Genie which is this model

of router that I'm using.

So, do I want to use the genie to help me?

I'm going to say no, we're going to configure this ourself.

Now, currently, I do not have my cable modem

or fiber modem plugged in so there will be

no connection to the Internet,

but I do want to go through and configure

the wireless settings.

So, I'm going to start by clicking on Wireless

and under here you can see the first thing

that we want to turn off which is Enable SSID Broadcast.

According to the Network+ exam

and the Security+ exam, you should

disable the SSID broadcast because this

is essentially your wireless access point

going out and saying, hey, hey I'm over here,

connect to me, my name is blank.

We don't want to do that, so instead we're

going to turn that off which means

that each device in your area,

you're going to have to actually type in

the name of the network for them to connect.

Then, do we want to have Wireless Isolation?

I'm going to say yes.

Now, the reason why is I'm using a Wireless-N

router in this case.

Wireless-N and Wireless-AC do support

Wireless Isolation, this allows it

to act more like a switch and less like a hub

and that's what we'd like.

So, we're going to go ahead and give it a name,

and what is this SSID going to be called?

I'm going to go ahead and call it Diontestwap,

that's fine, and then it has you select

the region, I'm in North America

cause I'm in the United States,

and you can either auto select the channel

or specifically select the channel you want based

on one through 11 if your running Wireless-B or G.

Now, I'm going to let it auto select

for me based on what is in my area,

but if that was a problem, I could always go back

and select one of the three most common channels

that give us that separation, channel one,

channel six, or channel 11.

Next, I'm going to look at mode,

and mode tells me how fast it's going to operate,

am I going to be operating under Wireless-B or G,

which would be 54 or can I go up

to 150, which would be a mixed mode between G and N

or can I go up to 300 which would give me just a Wireless-N?

In my case, I do want to have this mixed mode

because maybe I have some older devices

that are still using Wireless-G

and so, we'll do that.

Then, we're going to look at our security options.

Are we going to have no security,

meaning, no password is needed?

Now, sometimes, you may want that.

For example, at our offices, we have a

wireless network called dionguest,

it has no password, you can go ahead

and connect to it, and it's going to give

you direct connection out to the Internet.

It's isolated and there's nothing

touching our network, it just gives you direct access out.

But if you're setting this up for your home,

you want to have a password cause you don't

want somebody connecting into it

and then touching your other devices.

So, on this particular wireless access point, it only

supports two different types of encryption, WPA or WPA2.

Notice, WEP isn't here, why is that?

Well, because WEP is easy to crack

and I'm going to show you that in a separate video.

But for right now, we have to choose

between WPA and WPA2.

Do we want WPA with a pre-shared key

and using TKIP or do we want WPA2

with a pre-shared key using AES,

or do we want to support both of those,

or do we want to support an enterprise mode?

Well, if we're a home user, we're probably

going to go for the most secure and easiest to use

which is WPA2 with a pre-shared key using AES.

And here's where you're going to choose

some long passphrase and you want it

to be something long and complicated

and maybe it's something like that, I don't know.

Or, maybe you have it as a long sentence,

whatever it is you want to have something

between eight and 63 characters

and you want it to be long and complex

because that lengthens the time it takes

for somebody to break into it.

So, we're going to go ahead and hit apply

and that'll save those settings.

Now, there wasn't a whole lot of in-depth

setting here, right?

They only gave me very basic things

because they're trying to keep it easy

for the consumer.

What I want to do is I want to go to the Advance tab though

and see if there's any more in-depth settings

that we might be able to use.

So, now that I went to Advanced,

I'm going to go to Setup and I'm going to go to Wireless

and we're going to see what settings we have.

Again, there's not much there.

Now, if I go to Guest Network,

this particular access point allows me

to have two different networks.

I can have one for my personal and one for guest

and the guest can connect and go directly

out to the Internet, just as in the example

I gave you at our business offices.

So, maybe you want to do that for your friends

and you're going to call it friendguestnetwork

and you're going to allow isolation

and you're going to enable this guest network

and you're going to allow it to be broadcast.

We're not going to allow guests to access

your local area network, though.

We want them to go directly to the Internet

and not touch anything inside your network.

And we can go ahead and set that up.

Another thing we might want to do

is we might want to use MAC filtering.

So, if I want to enable MAC filtering,

I need to find it first, and I believe

it's under Advanced Setup here.

And then, we're going to go down here

and find it under Wireless Settings.

And then under Wireless Settings,

they call it wireless card access list

and if I set up this access list,

I can actually turn it on and only

allow certain MAC addresses to be able

to connect to this wireless network.

So, the good thing about this is it will keep out

people who don't know you're using MAC filtering.

The bad thing is, as a hacker or an attacker,

it only takes me about 30 seconds

to bypass MAC filtering and so really it's

a lot of work for you to be able

to keep somebody out for maybe 30 seconds.

But if you wanted to use it, you could go

through and do it and we might say

something like jasonsiphone,

and then his MAC address, whatever

that MAC address happens to be.

And now, if I add that, it's going

to allow that wireless network card

to be able to connect to my wireless network

and it will prevent everybody else

if I turn access control on.

Now, that's not my real MAC address,

so I'm not going to turn that on

but that's just an example of what you can do.

The other thing I want you to look at here

is WPS and WPS is something that was put

into routers to make it easy for people.

It's that button on the front

of your wireless router, or wireless access point

that you push the button on your device

and you push the button on the access point

and they'll automatically pair,

share this router PIN with each other

and then connect each other securely to the network.

In theory, this was a great thing

but unfortunately, it was easily hacked

and so, it's something you do want

to turn off for your best security.

You'll notice on my device here,

it doesn't give me the option of turning it off

and so, I'm going to have to dig deep

into the settings to turn this off.

Most likely, it's here under the WPS Wizard,

or under the Advanced Settings

and we would go through and turn off

that WPS if you're allowed to by your device.

The last thing I want to talk about here

is your remote management.

If you click on Remote Management,

this is something where it allows you

to connect to the device remotely over the Internet

through this web-based graphical interface.

Now, we're doing this locally on 192.168.1.1

and that's okay because you'd have

to be connected to my network first

to be able to access this device

and make these changes.

But if I turned remote management on,

I can actually give it an IP address

and allow anyone on the Internet

to be able to connect to this device and make changes.

Now, why would you want to do that?

Maybe you have set this up for your mother's house

and she's not very technically savvy

and every time she has a problem,

she's going to call you and ask you to fix it.

So, if that was the case, you might want to

turn this on, but you're going to want to configure

it to only allow certain computers

with certain IPS to be able to connect to it.

Again, the best practice here is

to turn off remote management

and you'll notice it was off by default

and keep it off to keep your device

the most secure it can be.

So, in summary, what are some of the big steps we did?

Well, we wanted to make sure we're using WPA2

with a good, long, strong, pre-shared key.

We want to disable the SSID broadcast

to make it harder for somebody to find our wireless network.

We want to enable Wireless Isolation

to keep those channels and frequencies

isolated from each other from people connecting

and make it act more like a switch and less like a hub.

We also want to enable MAC filtering

according to the exam, although honestly,

in reality, I usually don't do MAC filtering

because it's just more of a pain for me

and it really doesn't give me that much more security.

And finally, we want to disable the WPS

setting, if you're able to.

Again, WPS was a great idea for convenience

but it doesn't provide good security

and so, I would disable that anytime you can.

I hope you take these tips and you put them

to work in your own home or office network

and get yourself a little bit more secure.

In this lesson, I'm going to demonstrate how to conduct

an initialization vector attack

on a WEP-protected access point.

As I said before, WEP is extremely insecure

because it only uses a 24-bit initialization vector.

Regardless of what key you choose,

this attack is going to work every single time.

This is the reason that I say

you never ever want to use WEP in your networks.

If you find a network using WEP in your organization,

you should immediately work to update it to WPA2, instead.

Let's jump into the lab

and I'll show you exactly how this works.

So, the first thing we're going to do

is we're going to start with airodump-ng

and then the card that we have which is wlan0mon

and notice it's starting to scan

for that particular network that we're looking for.

In our case, we already found it.

It is WirelessHacking, this WEP network right here.

And this is the BSSID or the MAC address for that network.

So, for us to attack it,

we are going to use airodump-ng again

and in this case, we are going to specifically tell it

which channel we want to go after, which is channel 1

right here from the WirelessHacking network.

We want to go after the BSSID

that was provided for that network.

And we want to go ahead and write that data to a file

which is going to be WirelessHackingDump

it's what we're going to call that file.

And then, we're going to give it the card itself

which is wlan0mon and hit Enter

and off it goes starting to scan the network

which is helpful but we're not quite there yet.

Notice, the data packets are climbing

but we haven't yet associated ourself to that network

to be able to start doing things like packet injection

and capturing those initialization vectors.

So, I'm going to go ahead and put this up here

to make some extra room

and we'll just bring that right across the top

and let it continue to run.

We're going to open up a new terminal

and I'm going to bring that down here to the bottom.

Now, in the new terminal,

what I need to do is I need to start doing

authentication to the network using fake authentication,

which is our first step in the hack.

So, that first step in the hack

is that we are going to do a program called aireplay

and in aireplay-ng,

we are going to use fakeauth as our command,

0 for infinite attempts,

dash a, and the MAC address that we're going after,

which again, we still have pasted right there.

And then, we're going to use the MAC address

that we're coming from

which we have to find ourself

so we are going to open up another terminal.

You can see how you start getting quite a few terminals

and just type in something like ifconfig.

When you do that,

you're going to get the MAC address for wlan0mon

and the first 12 digits here is that MAC address

for our network card.

So, I'm just going to copy that

and then, we can paste that in.

Now, this uses dashes but for this particular command,

you have to use colons

so, I'm going to arrow through and change those to colons

as you can see

and the command's not done yet

cause what's the one thing we haven't told it?

We haven't told it which card to use.

So, we have to use wlan0mon.

And then, we will hit Enter

and off it goes sending a authentication.

We now have an authentication made with this network.

So, we can move into the second phase of our attack

which is going to be the packet injection.

So, for the packet injection,

we are going to still use the aireplay command

and most of it is going to be the same.

So, what I'm going to do instead of typing it all

is hit the up arrow

which will bring back the last command I used.

The big differences here is

we are not going to use fake authentication anymore.

Instead, we want to use an arpreplay

so that we can create additional traffic on this network.

Instead of a for the access point,

we're going to use b for the access point,

which tells us that that's the base station.

We're still going to use the card that we're coming from

and the network card wlan0mon.

When we hit Enter, off it goes

and notice that we have a couple of ARP packets here

and our data is going to start going up.

We have a lot of frame loss.

Once you have a couple of ARP requests

that have been successful,

you can hit Control + C and stop that.

Now, with this attack,

it does help if this is a busy network.

Right now as we're doing this,

you can see the data packets are going up.

The reason those data packets are going up

is because I'm streaming YouTube on the device,

this base station here,

this client which is my iPhone

is talking to this access point and streaming YouTube

which is collecting a lot of data.

Now, the next thing you want to do is start cracking

and every 5,000 data packets that go up,

it will start trying to do another attempt

and it's really easy.

You just use aircrack-ng

and then the filename of what you're going to be using.

So, let me clear the screen here

and the file that I'm going to be using is

WirelessHackingDump.02.cap.

And the reason it's the second one

is because I've run this attempt once before showing you.

So, all we're going to use is aircrack-ng

and then the filename that you're going after and hit Enter

and off it goes, starting to crack away.

Right now, it already has

14,000 initialization vectors collected

and you could see that here from that data

but that wasn't enough.

So, when this hits 15,000,

you're going to see this kick off again

without me doing anything

and we'll see if we can crack that key.

So, here it goes again.

It's going off and testing the different keys

and it didn't find it so it'll try again at 20,000.

Generally, it's going to find it

somewhere between 10,000 and 25,000.

It really depends on where that particular key is

inside the key space,

depending on what that hexadecimal password was

that we used.

So, again, you can see the data packets climbing up

as I'm streaming different YouTube videos.

Every time I start another video,

it starts downloading all that data.

All those frames have an initialization vector in there

and they're able to be captured

so that we can start seeing that information.

So now, we have over 20,000.

It's going to try again.

And there it is.

It found our key 17:25:83:AE:FA.

So, we now have a key.

What are we going to do with it?

Well, the next thing we want to do

is we want to see if that key actually works

and be able to get onto a network.

We can do that through Kali

or we can do it through your Windows machine

or your Mac machine.

It depends on where your ultimate goal is.

For this example, I'm going to show you

how to use it inside your Macintosh machine.

You can do the same thing in Windows and again in Kali.

So, if we can cancel this capturing at this point,

so we hit Control + C,

and we're going to switch back to our client machine,

in my case Macintosh,

so, now that we're back on our Windows

or our Macintosh machine,

you'll connect to that wireless network,

just like you normally do.

So, we're going to go down to WirelessHacking

and it's going to ask us for the passcode.

My passcode that we just cracked was 17:25:83:AE:FA.

And if I go ahead and join,

we should see if I can pull an IP address from this network.

And if we look at it,

you can see here we did pull an IP address from this network

and we are connected to that access point

starting with c8.a7, that BSSID,

which is the one for WirelessHacking.

So, our hack did work and it was successful.