So you have set up your 48 and it's now time to connect your local area network into one of its interfaces.
On the other side on the Internet facing interface your when interface you will connect it to your ISP
and assume that you have dozens or even hundreds of computers and only one public IP address.
What can you do.
Well you use net network address translation you're 48 acts as an agent that translates private IP addresses
into your one public IP address without net.
We would have need to purchase a full class address range for our computers.
Now what does that do 48 actually changes the IP address clear of every packet.
So just imagine that by using a 24 subnet you can use up to 200 and 54 IP addresses.
That's amazing.
Using only one public IP address.
Now there are several types of Net.
We will look at them.
There is the part which is the port address translation in 48.
We call it net overload.
There is the central net there is the virtual IP.
But before we go over to the different types of net we need to understand or to distinguish between
two types of net for an outgoing traffic.
We use a source net for incoming traffic.
We use destination net and net as you will see is part of your firewall policy.
It is integrated with it and you will use it in different scenarios.