Which if the following statements are FALSE?
A.
Dynamic NAT cannot be used for protocols where the port number cannot be changed.
B.
Dynamic NAT cannot be used when an external server must distinguish between clients bases
on their IP addresses.
C.
With Dynamic NAT, packet’s source port numbers are modified.
D.
In Dynamic NAT, public internal addresses are hidden behind a single private external address
using dynamically assigned port numbers to distinguish between them.
E.
Dynamically assigned post numbers are used to distinguish between hidden private addresses.
Explanation:
This statement is false because in the inside we have Private Internal Addresses and in the
outside we have Public External Addresses and not the opposite.
Incorrect Answers:
A: You can’t use protocols where you can’t change the ports, remember that the translation
changes the sources ports to distinguish between the different NAT clients.
B: You can’t use dynamic NAT to advertise servers from the inside, you have Static NAT for that
matter. There is no way to distinguish the internal server from the outside.
C: When Dynamic NAT takes place, the source port number is modified by the firewall so it can
know where to redirect the reply when it’s coming back. The firewall have a database with thismappings, it contains the original source port and the source port after the translation, it also
contains the real source IP.
E: This is true, the firewall recognizes the different internal host with the internal source port
mapping database used to make the sources port changes in the NAT process.