What is NAT

What is NAT Filtering?

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PUREVPNDigital SecurityWhat is NAT Filtering?

What is NAT?

NAT stands for Network Address Translation. This is a service that’s used in routers. Its purpose is to translate a set of IP addresses to another set of IP addresses.

The primary reason for a NAT is to help preserve the limited amount of IPv4 public IP addresses that are available around the world.

NAT comes equipped with lower-end to business tier routers available in the market. Besides, NAT allows several devices (mobile phones, laptops, Smart TVs) to connect to the internet using a single IP address provided by ISP.

What is NAT Filtering?

NAT filtering adds a layer of security on your internet network, securing you against cyber threats. Think of NAT Filtering as the first line of defense which combats hackers from injecting malware data packets on your device(s).

Mainly, NAT filtering inspects each data packet before it decides what to do with those data packets. With that in mind, NAT filtering’s constant supervision limits any unwanted incoming traffic from entering into your internet connection.

Once NAT filtering receives intended data packets, it passes them on to the right intended device. NAT and NAT filtering are actively working on your router. During the filtering process, if NAT comes across any unidentified source or hacker, the NAT firewall takes over.

What is a NAT Firewall?

A NAT firewall works by only permitting internet traffic to pass through the gateway if a device on the private network has requested for it. Any uninvited requests or data packets are discarded, preventing communication with potentially dangerous devices on the internet.

If inbound internet traffic does not have a private IP address to forward to beyond the gateway, the NAT firewall knows the traffic is unsolicited and should be discarded. That’s how NAT filtering is performed and protects users against harmful cyber threats.

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What is NAT Mapping? 

Network Address Translation (NAT), or NAT Mapping, is a communication technology used in private networks to combine several personal IP addresses into a single public IP address for communication with the outside world.

Therefore, private IP addresses are not required to give a separate, distinctive public IP address to communicate with the public Internet. By isolating local resources from the Internet, many services and ISPs (Internet service providers) employ NAT mapping to protect the finite amount of IPv4 addresses still accessible and add more protection.

In-depth explanation of how NAT mapping works

NAT mapping works by allowing an internal network’s users to access outside networks through a single gateway connection, such as a broadband router. The router assigns each internal user a unique private IP address, but then replaces that private address with its own public address when sending data out on the Internet. 

When replies are received from external sources, the router uses its NAT rules to translate them back into their corresponding local private IPs for delivery within the internal network. 

By translating between two different addressing systems, NAT allows connections that would otherwise not be possible due to incompatible addresses.

In addition to conserving addresses and increasing security, NAT mapping also helps protect against malicious data traffic and provides flexibility in configuring services and applications within local networks. 

Without NAT, nearly every device on an internal network would require its own publicly routable IP address in order to access outside networks or services; however, with NAT mapping many devices can share a single public IP address while still being able to communicate both locally and externally.

NAT Filtering on PS4

When it comes to the online gaming world, NAT filtering plays a crucial role. If you are among those who aren’t facing any NAT errors on their PS4 gaming console, you’re truly blessed. We highly encourage you to don’t play with your router’s NAT settings.

Often, NAT issues occur when there’s a communication error between a PS4 and the server or the router. In PS4, NAT types are classified as Type 1, Type 2, and Type 3.

Type 1 Type 2 Type 3
Open Moderate Strict

In essence, anyone with Type 1 will experience uninterrupted online gameplay. A person with Type 2 will face certain interruptions in their gaming experience while a person with Type 3 will not be able to host gameplay nor receive chat messages properly.

In short, it’s recommended that you choose NAT Type 1 to enjoy seamless connectivity and a refined online gaming experience.

NAT Filtering on Xbox One

PS4’s major competitor, XBOX One, also suffers from NAT type issues. With an Xbox, NAT issues are pretty common, and they completely disrupt your flow if you’re unable to connect with an online player.

Online gamers have to manually set the NAT Type to Open when they’re getting Moderate or Strict NAT settings. With Open NAT settings, players can conveniently communicate with each other and play online games without interruptions.

Learn how to change NAT type on an Xbox One.

Frequently Asked Questions

Should NAT filtering be open or secured?

Filtering should be reserved for NAT (Network Address Translation). It adds an extra level of protection to prevent unauthorized access to your network resources and helps protect your network by stopping harmful traffic from moving in or out. If you want to add additional protection from external threats or attacks, you must enable NAT filtering. 

How is NAT filtering done?

Traffic from an IP address is allowed or denied through Network Address Translation (NAT) filtering based on rules. Using attributes such as source/destination IP addresses, port numbers, protocol type, and others in NAT filtering to allow or deny incoming and outgoing traffic NAT filtering rules are typically defined at the router level to block accessing a particular website.

What does NAT mean in a firewall?

NAT stands for Network Address Translation, which is a process in firewall networks used to public IP addresses to private IP addresses. NAT allows multiple devices on a network to share one public IP address, allowing for the use of the internet more efficiently. Plus, NAT increases security by hiding internal computers from external connections.




June 27, 2023


12 months ago

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