In this video I would like to give you a quick introduction to what is needed to do networking.
In the end, all networking ends in the Internet.
That's where you want to go to.
But if you work in bigger network environments, well, you have your local network and
maybe you even have more than one local network represented by these white lines.
First thing you need to do to make networking possible, you need to connect the networks together.
And that is by using R, which stands for router.
So your network needs to have a router to get to the Internet. And if you
have two local networks, then you need a router to connect the networks together as well.
Then you have your own computers which are the nodes on the
different network networks and they need to be provided with addresses.
IPv4 is the default addressing.
And to start with, every network needs its own network.
And to start with, every network needs its own IP network address.
Like 192.168.0.0 24.
We indicate 24 to tell the network address that the first three
bytes are for networking and the last byte is for node addressing.
And that means that if we have 2, 3, 4 and a 1 right here, that we have these IP addresses.
192.168.0.1192.168.0.2 and so on.
And if you have different networks, every network needs its own IP address.
So let's say this is 192.168.1.0 24, where
the nodes also have their unique IP addresses.
And we need the IP address on the router as well.
Now, big question is what is a node going to do if it wants to go to the Internet?
Let's say this guy wants to reach out to the Internet. Well, imagine the flow.
Then it needs to go through the router, from this router to another router where the packet will end on the Internet.
In order to get this done, we have the setting of the default gateway.
The default gateway is always a router on the network that is required to go externally.
So for this node, this will be the default gateway.
And what does that mean?
Well, if we look at the IP address that will be 192.168.0.1.
Frequently you will see that the default gateway is either the lowest or the highest IP address in the network.
Now that would allow you to reach nodes on the Internet by IP address.
Most people want to make it a little bit easier. And in order to make it easier, there is a system called DNS.
DNS is the domain name system.
So if you want to use domain names like google.com for instance, that's a DNS name and you
need to find the IP address that belongs to the domain name that you want to use.
That is why on every node that you are going to configure with IPv4, you need three different settings.
You need the setting of the local IP address, you need the setting of the default gateway, and
you need the setting of the DNS. And once that is configured, you can communicate on the Internet.
Sometimes it doesn't work well and then you need to investigate what is going on.