- [Instructor] Wifi analyzers are tools
that can identify wireless networks
on the 2.4 gigahertz and 5 gigahertz frequencies.
These tools can show things such as the channels being used
by your current access points
and also neighboring wireless networks,
the signal strength of access points
usually measured in dBm,
any overlapping that might be occurring
between neighboring networks and yours,
and also the best channels to use
for your new access points.
They come in two types.
You have the handheld all-in-one devices
with built-in wifi antenna, a touchscreen,
and incorporated analysis programs
like the one that we see here.
This is just one example and these are much more expensive.
And then there are the various apps.
You have them for Windows, for Android, and for iOS.
Whatever device you run the app on
has to have a properly setup wireless network adapter.
So let's take a look at a basic wifi app
running on a smartphone now.
And what we have here,
this is displaying the 2.4 gigahertz frequency range
and the wifi networks in the general vicinity.
As you can see, the lower channels,
one through five are being used much more
than the upper channels.
This type of data should play
into your decision-making process
when you're setting up a new wifi network
or when you're selecting an access point
to connect a client to if there's more than one.
So here you can see this information
and it's changing slightly as time goes by,
but we have a lot of networks
on the channels one through five
and only two between 6 and 11.
Now that's the 2.4 gigahertz frequency.
We can also select the 5 gigahertz frequency range
to see what's running there.
And you can see that there's really nothing.
There's only one in the lower frequency range for that,
so that should play
into your decision-making process for this.
But 2.4 is a lot more crowded.
It has a smaller channel width for each channel.
So that's quite often what we're paying more attention to
'cause there's a lot more of a chance for overlap.
So on the bottom, you see the channel numbers.
And in the United States,
we use 1 through 11 for 2.4 gigahertz.
And on the left, you see the dBm rating.
The lower the number, the better the connectivity.
And we have other options here.
We can see these in different graphical formats.
We can take a look at what this app thinks
are the best channels to use
and it's saying right now 10 and 11
and five, six, and seven are the best to use.
And then you can look at the actual dBm rating
for each of these networks
and see the frequency they are using
which corresponds to the channel
and what type of encryption they're using as well
and the MAC address of that device, which is pretty cool.
And it also gives you estimated distances
to these access points, but that's usually gonna be,
that's not gonna be very accurate with most of these apps
and that'll also depend on what device
you're running this on.
So that's an example of a wifi analyzer,
definitely something that you want to take a look at.
You wanna kinda stay away from other wireless networks
that are nearby channel wise,
but also look for the ones that have the strongest signal.
Those are the ones
you're gonna wanna stay away from as well.
And again, that's for the 2.4 and for 5 gigahertz as well
because the 5 gigahertz we use that all the time
with 802.11ac and other technologies.
All right, so a little bit about wifi analyzers
and that's it for this video.