What is Network Address Translation (NAT) Firewall?

Ruheni Mathenge  - Streaming Expert
Last updated: October 28, 2023
Read time: 13 minutes

A NAT firewall can be beneficial or an obstacle depending on what angle you look at. Check out this guide as we explain in detail what a NAT firewall is and how it works.

Network Address Translation (NAT) is the process of assigning one shared public IP address while allotting unique private IPs to all the devices connected within a network. This way, a NAT firewall ensures online safety via offering a single gateway to multiple devices in the network for accessing the internet and hiding the private IP. Moreover, the NAT firewall detects and blocks any connection request from outside the network, thus preventing malicious cyberattack attempts on your device. Yet, NAT firewalls may cause hindrance in other networking activities, like torrenting. In this guide, let’s dig out more about NAT firewall and its limitations and benefits.

NAT is a method of modifying an IP address by changing the information in the IP header. This enables several devices on a private network to use the same gateway to the internet.

Although the devices will share a similar public IP address, they will have unique private IP addresses. Most VPNs and WiFi routers offer these gateways. For instance, all the devices connected to the router will use the router’s public address, but each will have a different private IP address.

How do NAT works? The process isn’t as complicated as it seems. Essentially, when you access a web page, your device will direct a request to the router with a private IP address. Then, the router will change the request and send it to the site’s server using its public IP address. Finally, the server replies to the request, and the router sends it to your device through the private IP address.

On the other hand, a firewall is a protective layer that blocks unsolicited communications between devices. So, a NAT firewall permits only the traffic that has been requested by a device on the network to pass the gateway.

In fact, it discards malicious data packets or requests, effectively preventing potential dangerous connections. In addition, the firewall will mark any incoming traffic without a private network as unsolicited and destroy it.