Network Address Translation Flashcards
What is the private IP address range for class A?
10.0.0.0/8 - 10.255.255.255
What is the private IP address range for class B?
172.16.0.0/12 - 172.31.255.255
What is the private IP address range for class C?
192.168.0.0 - 192.168.255.255
IPv6 uses how many bit addresses vs IPv4?
IPv6 - 128
IPv4 - 32
What kind of NAT would a mail server or public web server use to connect to incoming connections?
Static NAT (one-to-one mapping)
What kind of NAT would host use (don’t need to accept incoming connections)
Dynamic NAT (first come, first served basis)
Inside global address
This is the address if someone in the outside network is sending traffic in. This would be THEIR destination address
Inside Local
IP address configured on my host OS (inside the network)
Outside Local
The IP address of the host outside our network that we are sending traffic to. (What our network seeing from the inside)
For one way NAT, the outside local and outside global will be ______
the same (different port, same IP)
Outside Global
The IP address of the host outside our network that isn’t NAT. It’s actually IP address assigned to it
How do you configure static NAT?
int f#
ip NAT outside
int f#
IP NAT inside
IP NAT inside source static X.X.X.X (inside local) X.X.X.X (inside global)
In Dynamic NAT, how many public IP addresses would you need if you had 30 host?
30 Public IP addresses
It’s a 1-1 for Dynamic NAT
How do you configure a pool of global addresses
IP NAT pool (give it a name) X.X.X.X X.X.X.X netmask 255.255.255.240
*IP addresses are your pool’s range i.e. 203.0.113.4 203.0.113.14
What do you do after you configure your pool of global addresses
Create an access list for all the IP addresses we want to translate (inside local)
What is the command to configure an access list for all the IP addresses we want to translate (inside local)
access-list # permit X.X.X.X (inside local IP subnet) X.X.X.X (wildcard for subnet)
What is the last step to configure Dynamic NAT
Connect the access list with the NAT pool
What is the command to Connect the access list with the NAT pool?
IP NAT inside source list # (access-list number) pool (name of the pool)
NAT Types: PAT (port address Translation
Allows the same IP address to be re-used
*Unlike Dynamic NAT
How does Dynamic NAT with Overload track IP addresses?
It uses the same IP address but tracks the source port it used in the translation table
How do you configure PAT in a router?
Same steps as Dynamic but when connecting access-list and pool together add overload at the end of command
>IP NAT inside source list # (access-list number) pool (name of the pool) overload
OR
>IP NAT inside source list # (access-list number) interface# (outside) overload
What is the command to verify your NAT translations?
> show ip nat translations
