You need to know the difference between an ad hoc mode, wireless network and an infrastructure mode
wireless network.
In ad hoc mode, we have two devices as an example that talk directly to each other.
So in this example, I've got two Windows laptops and I'm going to show you how to set them up using
ad hoc mode so that we can set them up to talk to each other directly without an access point.
Typically these days we use infrastructure mode where we have a wireless access point or wireless router,
and communication from device to device is via the access point.
So they don't talk directly to each other.
They talk to each other through or via the access point.
Okay.
A little bit of theory by design.
ADA 2.11 Networks of Flexible.
ADA 2.11 is the triple E standard for wi fi.
So we have examples such as ADA 2.11 AX That's wi fi six or 82.11 AC That's a wi fi five.
We have other examples.
ADA 2.11 A, B, G and N.
As an example, there are three types of topologies.
We have what is called independent basic service sets, or IBC.
That's basically an ad hoc network.
That's what we covering in this video.
We've got basic service set and extended service set.
These use infrastructure mode.
A service set is basically a logical grouping of devices.
In this example, I'm using wi fi Explorer Pro to see which networks are being advertised and which
networks.
My MacBook can see there's a free version of this that you can download for Mac if you've got a Windows
computer.
I would suggest that you download WiFi analyzer.
This is a free application that you can get from the Windows store and this gives you similar kind of
information.
Not as detailed, but it'll allow me to see which networks are being broadcast.
We can see the power.
We can see which encryption modes are being used.
Which standard is being used?
So this is 82.11 AC as an example.
Scrolling down.
We can see that the Netgear 75 supports 82.11 a x so wi fi six.
We can see similar information in wi fi explorer pro in this example.
It's showing that wi fi five is used by that.
Netgear does actually support wi fi six, but we can see other information such as which channels are
being used by various access points for both 2.4 gigahertz as well as five gigahertz.
So as an example, in the 2.4 gigahertz range, the Netgear is using all of these channels.
It's using a wide channel width of 40 megahertz in the five gigahertz range.
It's using a channel width of 160 megahertz.
So it's using a wide range of channels to basically allow me to get better throughput.
Okay.
But going back to the theory, the one that we interested in is OC mode, also known as independent
basic service set.
This is where we connect to the clients without an access point.
So I'm going to connect those two laptops directly to one another without the use of an access point.
But you need to make sure that the network interface card supports this capability.
So I'll show you how to determine that on both these laptops.
In infrastructure mode, we have an access point.
An access point could be something like this.
This is a Cisco access point.
This access point supports Wi-Fi six.
Quite an expensive access point.
You need to typically configure this with a wireless controller.
So this is not the only device that's used.
Access points from Cisco, such as the support either lightweight mode where they are controlled by
an external controller, or they can be autonomous access points where they do everything themselves.
That depends on the access point.
Here's an example of a home router.
This is a tp-link router.
Notice it has wireless antennas.
This acts as a router as well as an access point.
This is a dedicated access point.
Okay, so when we using infrastructure mode, the access point is connected to a physical network such
as a switch.
So the access point is connected to physical infrastructure.
But we've only got one access point.
I mean, for your home Internet router as an example, this router has Ethernet ports and an Internet
port, so it's not just going to be there by itself.
You are connecting this device to a physical infrastructure.
So as an example, you may have a printer that doesn't support WiFi, so you would connect it to the
physical network using Ethernet cables, and then you'd be able to print to that printer through wi
fi onto the physical Ethernet network.
But I mean, the most common example is that you want to connect to the Internet, either via cable
or DSL or some other type of technology, fibre to home, maybe.
So this connection allows me to connect through wi fi onto the internet.
So hence the term infrastructure mode.
We are connecting to some type of infrastructure.
So the access point may be connected to a switch, which may be connected to a router, which may be
connected to the Internet as an example.
Now, in a extended service set, we have multiple access points.
Now, this may be fine for your home network, but it's not going to work if you've got a large campus
or a large university environment.
In that case, you need multiple access points.
You wouldn't run an entire university on one access point.
It's not going to work very well.
There are many reasons.
Obviously, one of them is distance.
The power from this access point can only broadcast the signal a certain distance.
It won't cover the entire university campus.
And obviously you don't want thousands of people connected to one access point.
The Internet throughput would be terrible.
They wouldn't be able to browse the Internet or do very much if everyone's connecting to a single access
point.
So the idea is, is that you have two or more basic service sets to give you an extended service set.
So we have multiple access points.
In this example, we've got two access points connecting to a single switch.
Obviously, in a large campus environment or large university environment, you're going to have many
access points, many switches, many devices to give you the scale to handle thousands of students or
thousands of employees.
So this switch may, as an example, connect to a router which again can access to the Internet.
It's connected via a common distribution system, in other words, a common physical network that allows
multiple users to connect to the wi fi network and then get to the Internet or get to servers and other
systems on the physical network.
So these are the steps to configure an ad hoc network.
On a Windows computer.
First thing we need to do is open a command prompt.
As an administrator, you need to make sure that your card supports this feature.
I'll show you two examples that Windows ten Laptop doesn't support the feature.
Windows eight laptop does.
Next thing we need to do is set up a ad hoc wifi network.
So we're going to use this command and set up a side and SSID is a service set identifier that's basically
a name for a network, a human readable name.
So going back to my Windows computer.
Notice ABC one five gigahertz is the SSID for this network, but there is the MAC address of the network.
On WiFi Explorer it shows you that a little bit better.
So as an example, here are the basic service set identifiers.
In other words, the MAC addresses of the access points.
And then we've got the network name SSIDs or these.
Notice she has a hidden network, but that doesn't stop me finding it.
So even if you don't broadcast and ssid very easy to find networks out there using applications like
this.
So here are different networks.
This is IDs and they basic service set identifiers, which is essentially the MAC address.
So basically the basic service set identifier is the MAC address of the human name that's broadcast
into the air.
That's typically what you're going to see as an example when you.
Look on your laptop and you look for all the networks that are being advertised so that you can connect
to the correct network.
You also need to specify the key, which is basically the password to connect to the wi fi network.
And then the last step is to actually start the network.
Once you've finished, you would type the command stop to stop that network from being broadcast.
But initially, you've got to stop the network and advertise it.