TestOut Labs Practice Test

NAT is a technique that lets devices on a private network reach external networks by changing the IP address information in packets as they pass through a router. The broad goal is to map private addresses to public addresses so traffic can be routed on the Internet.

PAT is a specific form of NAT often called NAT overload. It allows many private addresses to share a single public IP by using different port numbers to keep each connection separate. In practice, the router keeps a translation table that ties each internal private IP and source port to the public IP and a unique outside port. This is what lets multiple devices, all using the same public IP, communicate with external hosts without conflicts.

So NAT provides the general idea of translating internal addresses for external use, while PAT is the common method that uses port numbers to multiplex many private connections onto one public IP. The other statements aren’t accurate because NAT is not limited to IPv6, it isn’t solely DNS translation, and NAT can be used in several forms (not just a one-to-one mapping).