CompTIA Network+ Practice Test

Which component performs Network Address Translation (NAT)?

1. The switch

2. The firewall

3. The router

4. The modem

The correct answer is: The router

The component responsible for performing Network Address Translation (NAT) is the router. NAT is a technique that allows private IP addresses within a local network to be translated into a single public IP address before the data packets are sent to external networks, such as the internet. This is essential for conserving public IP addresses and managing the internal addresses in a local network. Routers manage traffic between different networks and perform routing functions, which includes the ability to translate addresses. When data returns from the internet, the router can then map the public IP address back to the appropriate private IP address for delivery to the correct device in the local network. While firewalls often work in conjunction with routers and may have NAT capabilities in certain configurations, the primary role of NAT is typically associated with routers. Switches operate primarily at the data link layer and do not handle IP address translation, while modems facilitate the connection to the ISP but do not perform NAT either. Thus, routers play a critical role in enabling NAT within a network.