Guide to Network Address Translation (NAT)

Network Address Translation, often referred to as NAT, plays a crucial role in managing IP address spaces in private networks and for enabling internet sharing.
What is NAT: The basic premise of NAT is its ability to translate local, private, not globally routable IP addresses into globally routable IP addresses. In doing so, NAT enables all the devices in a local network to access internet using a single public IP address.
Why NAT is important: NAT essentially increases IP addressing efficiency, extends the life of IPv4, and secures the network by hiding internal IP addresses.
How NAT works: When a device on the local network sends a request to a device on the Internet, the source IP address in the packet header is replaced with the public IP address of the NAT router. The destination sends a response that reaches the NAT router first, which then translates the public IP back into the local IP address of the device.
Exam Tips: Answering Questions on NAT: 1. When asked how NAT works, remember to explain the process of IP address translation from private to public and vice versa. 2. For any question calling for the benefits of NAT, always mention the efficiency in IP addressing, IPv4 survival, and network protection. 3. Usually, questions might ask you to differentiate between types of NAT such as dynamic and static NAT- remember, static NAT has a dedicated one-to-one link between local and global IP, while dynamic NAT does not.