So with dynamic net, once again you are creating a pool of inside global addresses.
The reason why it's called dynamic rather than static is the router dynamically allocates IP addresses
from the pool on a as needed basis.
The mapping will be removed once communication ends, so there's no permanent 1 to 1 mapping that's
always there, like you have with static Nat.
With dynamic Nat, the nat translations automatically created when they needed and torn down or remove
to when not needed.
Now, as I've been explaining.
Typically static nach is used when you have servers.
So where router one is a server is an example that needs to be accessible from the outside or internet.
Now, just to make sure that we cover the topics in the Q&A, I want to show you that router one is
able to ping router three when static nat has been configured on router two so show run pipe include
net.
We can see the static net translation here.
So we are translating ten 11128115 show IP net translations.
Notice there is our static net translation.
We are not netting the outside local and outside global in the static net.
Let's do a debug.
So debug IP net.
And what I'll do now is I'll telnet to 8112.
The Telnet connection is disconnected because I need a password on the side.
But what I'd like you to see is the source IP address.
Ten 111 was netted to 8115.
That's the inside global address.
The destination of the traffic is 8112.
We had a reply back from 8112.
Going to destination 8115, which is then translated to ten 111.
So traffic from right to one to router three is having the source address translated and then the return
traffic has the destination address translated.
We are doing source address translation of this IP address.
I'll enable telnet on the side, so I'll enable the two lines on this router.
And enable a enable password.
So we still running a debug show?
Debug shows me my net debugging is enabled and I'll telnet from router one to router three again.
We can see the net translations taking place again.
Source to destination.
I'll log in.
And let's enter one character.
So E.
You can see for the character.
E The source was translated from ten one one 1 to 8 115.
Going to a destination of 8112.
Reply came back and some other traffic was returned.
So an acknowledgement to write a three type MN.
We get to the same kind of translation.
Hit enter.
Same kind of translation is taking place.
So for every character that I enter in the Telnet session, net translations are taking place with ten
111 being translated to 81154 traffic going from inside to outside, and then 8115 is being translated
back to ten 1114 traffic from the outside to the inside.
In this example, we'll configure dynamic Nat in the topology.
We have two routers router one and router four that are on the inside.
They are connected via a switch to router two, which is going to do the actual network address.
Translation We'll configure dynamic Nat on router two to allow both router one and right of four to
access router three, which in our lab is deemed to be the internet.
So the eight network is on the outside.
That is the internet.
Ten 110 is our internal network with these three devices connected to each other via switch one.
Later on, I'll expand the topology to actually connect router three to the internet so that right of
one and router four can connect to sites such as google.com.