What devices do we have here?
This is a router.
This is a Cisco 43 21 router.
I've chosen this router specifically where I purchased this rather specifically because it's available
in packets.
So this is a Cisco 35 66 switch.
Again, 35, 60 switches are available in packets.
So you don't need to spend money buying all these devices.
I've done that for you.
Now, obviously, if you want to, you could buy physical equipment.
It's nice in some ways to work with physical equipment.
But for the Kenay, you don't have to use physical equipment.
If you can't afford it, just use a tracer and I'll show you in a moment when I boot up this router
and a switch and compare it to a tracer, you'll see it's very, very similar.
This is an example of a twenty nine 60 switch.
What I like about these switches is they found less.
So I have them on my desk here and it doesn't make a lot of noise and mess up the recordings.
But here we've got two interesting devices.
They look very similar, very similar to each other.
But what you'll notice, and these are older devices, is this is a Cisco A.S.A. 55 of five.
This is called a firewall.
Firewalls allow us to stop bad people getting into our network so we can restrict who can access our
network.
They use what are called firewall rules to permit or deny traffic.
This is a small little firewall typically used again in a small business.
The idea here is we can connect a bunch of devices directly to the firewall.
So it's acting like a switch in some ways.
But I could specify what's called the outside interface and the inside interface.
And I do not allow all this firewall does not allow traffic from the outside interface to the inside
interface unless you explicitly allow it.
Your home router probably does something similar.
It has a built in firewall.
Your PC may be also running a firewall, a software firewall directly on the PC.
This is an example of a hardware dedicated firewall.
Now, rodders, as mentioned, often have firewall functionality, but this is a dedicated firewall.
Now, you could connect your Internet directly to the firewall if you have an Internet connection and
then to the router and then to the switch where your inside devices are or your lan is all you could
connect to the router and then have the firewall behind the rudder.
So you either have the firewall in front of the router or behind the router.
In many cases, you're going to have this behind the router because your ISP may manage the router or
you need a physical connection, that's not Ethernet.
These devices typically only support Ethernet.
Rawda will support other types of technologies, such as Edsel or cable as an example.
So the Internet connects to the router, connects to the firewall, which then connects to your switch
in your internal network.
Now, here's another device.
Looks very much the same, but this is a wireless LAN controller and another small wireless LAN controller.
You'll notice the form factor looks exactly the same, but it has different functionality.
This is used to manage access points if you've only got one access point.
It makes sense to manage the access point directly using what's called an autonomous access point autonomous,
meaning that you don't need a wireless LAN controller to manage it.
But if you've got 100 of these or 500 of these, it's going to be a lot of work to manually configure
every one of those access points.
So rather than doing that, you use what's called lightweight to access points.
Some of these access points support both so they can either be lightweight or they can be autonomous.
Some of them have to be lightweight.
Access points varies depending on which one you buy.
But the idea is, is if I had 100 of these or 500 of these, they would register with the wireless LAN
controller.
Now, obviously, this is a small wireless LAN controller, so it's not going to support as many access
points.
But the idea is, if I have 100 access points, they would connect to the wireless LAN controller and
notice this doesn't have as many ports as as would be required.
The wireless LAN controller and the bigger ones, even more so, don't have so many interfaces.
They simply connect to switches.
So the access points connect to switches.
The wireless LAN controller connects to switches.
Switches are there to provide lots of ports to connect to in the network.
So the whole idea here is the wireless LAN controller will manage the access points rather than manually
managing every one of the access points to manage them through the wireless LAN controller.
So the wireless LAN controller will manage, let's say one hundred five hundred access points.
Depends on the controller.
Depends what it can support.
So once again, here we've got a firewall.
This is an older firewall.
USA Today.
We have what are called next generation firewalls.
They support features such as IPS or IDs now intrusion detection.
Let me give you an analogy so that you won't forget what intrusion detection is.
And it is like a dog.
What a dog can do is help protect you by warning you when there's an attack taking place.
Let's say you sleeping at night, sleeping comfortably in bed.
The dog, however, sniffs that there's an attacker, so an intruder, it sniffs that there's an intruder
trying to break into your house.
What does it do?
It barks.
It warns you that there's an intruder.
It doesn't stop the attacker.
It warns you that there's an attacker.
And then you can do something to stop the attacker trying to break into your house and intrusion detection
system simply detects that there's a problem and then alerts you that there's a problem and then you
have to do something about it.
An intrusion prevention system can alert you that there's a problem, but also block the attack so it
can prevent the attack.
So if someone breaks into your network remotely, let's say a hacker, it can see that there's malicious
activity on the network and then it can block that attacker.
So prevent that attacker from gaining access to your network.
Intrusion detection systems typically sit out of band of network traffic.
So the traffic is going past them, but they're not in the flow of traffic.
They just getting copies of the traffic to see if there's a problem.
And intrusion prevention system sits in line with the traffic.
So the traffic is going through the eyepiece or intrusion prevention system.
When there's an attack, it blocks it so the attacker can't get into your network.
So think of an I.D. or an IPS as a dog.
Is it a small dog ideas or is it a very large dog?
It can go in, attack the attacker.
Hopefully that analogy will help you never forget.
What an idea, solipsist.