10.3 Nat (Network Address Translation ) Flashcards
What is NAT (Network Address Translation)
allows you to connect a private network to the internet without obtaining registered addresses for every host. Private addresses are translated to the public address of the NAT router. NAT can be used to provide a measure of security for your private network or to provide internet connectivity with a limited number of registered IP addresses.
In NAT what is inside network
The inside network is the private network. A router interface that connects to the private network is also called the inside interface.
In NAT what is an outside network
The outside network is the public network (the internet). A router interface that connects to the public network is also called the outside interface.
What is a inside local address
The inside local address is the IP address of the host on the inside network.
What is a inside global address
The inside global address is the IP address of the host after it has been translated for use on the internet. The term global refers to the registered IP address that identifies the inside host on the internet.
What is a Outside global address
The outside global address is an IP address of an internet host. For example, when you visit a web site, your computer uses the global outside address to contact the web server.
What is a Outside local address
An outside local address is an outside global address that has been translated for inside (or private) use. In other words, the NAT router translates an internet host IP address into a private IP address. Instead of using the web server address, the internal computer will use the translated address.
Describe the Dynamic NAT method
Use dynamic translation to translate a range of outside addresses to a range of inside addresses. Use this option when you have multiple public addresses for multiple private addresses. If the number of inside addresses is greater than the number of outside addresses, use the overloaded option with dynamic NAT.
Describe the Static NAT method
Use static translation to translate a single outside address to a single inside address. To configure static NAT
Describe the Overloaded NAT or PAT method
Use overloaded NAT or Port Address Translation (PAT) to translate multiple inside addresses to a single public address. Port numbers are used to identify specific inside local hosts. The port number associated with the private host is appended to the inside global IP address. Use this option to allow multiple inside hosts to access the internet using a single public IP address.
router#clear ip nat translation
Deletes the dynamic entries in the NAT table.
router#show ip nat statistics
Displays counters for packets and NAT table entries, as well as basic configuration information.
router#show ip nat translations
Displays the NAT/PAT translation table entries.
