What is a NAT Firewall? How Does It Work and Do You Need One?
If you’re unsure about what exactly a NAT firewall is or what it does, stay on this page. Today’s guide teaches you everything you need to know about this essential cybersecurity technology, plus how to make it play nice with your VPN for the ultimate protection.
There are countless protocols that sit between you and the internet. Some are designed to carry data back and forth, while others speed the process up, perform error checking routines, and reassemble packets of information so they display as a unified whole.
Then there’s the technology designed to keep us safe. A NAT firewall falls into this category. It’s one of the early lines of defense against malicious attacks on our internet-connected devices, and it does its job without us even knowing it.
Boost the effectiveness of your NAT firewall (or replace it entirely) with these VPNs:
- NordVPN – Best Firewall VPN – Every one of NordVPN’s thousands of servers comes equipped with built-in firewall functionality, negating the need for you to create your own.
- Surfshark – Modern encryption protocols compatible with VPN passthrough, which frankly make separate firewall solutions unnecessary in most cases.
- ExpressVPN – Another provider with built-in NAT, offers blazing fast speeds and a huge network.
- PureVPN – A jack-of-all trades with myriad cybersecurity features not normally found in VPNs.
- VyprVPN – Equipped with network address translation filtering, an entirely self-owned server network, and uniquely powerful proprietary encryption.
Today’s primer walks you through everything you need to know about this technology, plus shares a few tips on how to further boost your security with a VPN.
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NAT Firewalls, the basics
The internet runs on packets of data. Countless numbers of these packets are sent back and forth each time you make a request, whether that be a simple website loading in your browser or a movie streaming to your TV. Packets need to be sent to precise locations, and to accomplish this, each one is stamped with an IP address. Each device that connects to the internet is assigned a unique IP, which acts a lot like a mailing address. This lets ISPs know who gets which piece of data so you actually receive the information you request.
To help handle the load of devices connecting from a single home, routers do much of the data packet sorting. Your internet service provider assigns you a single IP address when you connect. Your router then creates internal IPs for each device that connects through it. Turn on your phone’s Wi-Fi and it gets an internal IP. Switch on an e-reader, gaming console, tablet, etc. and they, too, get internal IPs. In short, when packets of data come to your router, it sorts them to the devices that are requesting the information.
This is where firewalls come into play. Just about everyone who’s used a computer knows that firewalls are tools that block unwanted data. This prevents malicious bots and hackers from sneaking into your computer through unauthorized connections. Only the traffic you specifically requested is allowed through; everything else is simply discarded or ignored.
NAT stands for Network Address Translation, which is a fancy way of saying “sorting.” According to IETF RFC 3022, routers use this process to modify the IP address information stamped on data packets so they know which connected device to send data to. A byproduct of this sorting process is filtering out unrecognized packets and discarding them, which is why it functions like a firewall. A NAT firewall ensures everything gets to where it needs to go and nothing extra is thrown into the mix.
Why do VPNs advertise NAT firewall features?
If your router already has this protection built in, why then do VPN services act like it’s such a special feature? The answer has to do with the way VPNs operate. When you run VPN software on your computer, it encrypts every packet of data that leaves your device. Encrypted data is unreadable to any person and any piece of hardware that doesn’t have the right cipher key, including your own devices.
Only two parties can unlock this encryption: your VPN software, and the VPN servers. Your router’s built-in filtering can’t read encrypted packet headers, so it simply passes data back and forth without knowing the IP address attached to it. This means that even malicious data will slip through local protections, as the router is essentially blind.
A VPN with NAT firewall features takes care of the sorting for you. Since the VPN sits between you and the internet, the service deploys this filtering on the outside of its servers. For example, you send encrypted data through your router and to the VPN’s network. The VPN decrypts it and handles the request (fetching a website or downloading a file). The VPN’s firewall filters out any unusual activity coming from the internet, then the correct information is encrypted and sent back to your computer. It performs essentially the same function as your router’s local protection, only since the local version can’t do its job with encrypted data in place, the VPN takes care of that for you.
Do you have to have a NAT Firewall?
Strictly speaking, the internet will still operate without a local or a VPN version of a NAT firewall in place. It’s not a good idea to go without one, however. This type of protection is a first line of defense against malicious attacks; it stops hackers before they even reach your device, which is the only way to ensure none of your data is taken.
This protection is even more useful when mobile devices and other non-PC hardware are involved. Nobody runs firewall software on their smartphone or gaming console, so what’s to stop a hacker from walking right in? If you’re troubleshooting console connectivity too, this Call of Duty NAT fix can help. A NAT firewall protects these devices without requiring any extra software installation.
You may be thinking “I’ve never been attacked before; I think I’ll be safe without this.” The only reason you think you’ve never been targeted by a hacker or a data bot is because the protection unceremoniously stopped it in its tracks.
Using firewall software with NAT firewalls
A NAT firewall isn’t perfect, and neither is the firewall software you can download and install. However, using both in tandem is an excellent method of filtering out as many unwanted connections as possible. Hackers are constantly looking for new ways to exploit bugs in the HTTP process or operating systems. It’s always better to have multiple overlapping forms of protection in place to ensure you stay safe.
How to choose the right VPN
Now that you know how useful a NAT firewall can be, you’ll want to search for the best VPNs that offer high security along with this type of filtering. It can be difficult to weigh all of the privacy and encryption options against speed and server distribution numbers, especially if this is the first time you’ve looked for a VPN. We used the criteria below to build a recommended list of VPNs with strong firewall capabilities. Use them to refine your own research so you can make an educated and cost-conscious selection.
- NAT firewall support – Most of the top-tier VPNs offer this feature as part of their service. Others provide similar workarounds to deliver the same level of protection.
- Encryption strength – The foundation of a VPN’s security rests upon its encryption strength. Most good-quality providers deliver 128-bit or 256-bit AES encryption to all of their servers, which is ideal for online activities.
- Logging policy – All of your traffic passes through a VPN’s servers. If they keep detailed logs of your browsing history, that data could end up in government or third-party hands. Make sure your VPN has a strict zero-logging policy that covers as many areas as possible, especially traffic and DNS requests.
- Software – To use a VPN, you need to be able to install it on all of your devices. This means having custom software for smartphones, tablets, laptops, and even Chromebooks. Make sure your most commonly used devices are covered by the VPN’s apps before signing up.
- Speed – Encryption adds data to each packet of information, which results in a slower download speed. Good VPNs can work around this limitation without sacrificing privacy by offering fast servers and customized software solutions.
Comparison Of The Best VPNs For NAT Firewall
- 24/7 Live Chat
- 24/7 Live Chat
- 24/7 Live Chat
- Yes
- 24/7 Live Chat
- Netflix,
- Disney+,
- Amazon Prime,
- iPlayer,
- YouTube,
- Hulu
- Netflix,
- Disney+,
- Amazon Prime,
- iPlayer
- Netflix,
- Disney+,
- Amazon Prime,
- iPlayer,
- YouTube,
- Hulu
- Netflix,
- Disney+,
- Amazon Prime,
- iPlayer,
- YouTube,
- Hulu
- Netflix,
- Disney+,
- Amazon Prime,
- iPlayer,
- YouTube,
- Hulu
Top-rated VPNs with NAT firewalls (or similar functionality)
With the above criteria in mind, we’ve gone to the trouble of narrowing down the crowded VPN market so you can make the best decision for your needs. We’ve rated each for its security, speed, usability, and of course, firewall functionality:
1. NordVPN
- Unblocks American Netflix
- GooglePlay users rating: 4.3/5.0
- Zero leaks: IP/DNS/WebRTC
- No logs and encrypted connections for total privacy
- 24/7 Live Chat
- Refund processing can take up to 30 days
While NordVPN no longer uses the outdated protocols which make VPN passthrough necessary on your router’s firewall, it’s not something you’ll miss. That’s because NordVPN features a built-in NAT firewall on its servers. Coupled with their unbreakable 256-bit AES encryption, no unwanted data requests will be invading your privacy.
Beyond its utility as a firewall solution, NordVPN also offers insane routing, with over 5,500 servers available in 59 countries. That means you can “spoof” a virtual IP in countries where content is normally geoblocked, like the various Netflix libraries. Moreover, NordVPN offers adblocking, a kill switch, and even DNS leak protection to keep you safe from a wide variety of threats.
And in terms of anonymity, NordVPN is tops. They’re based in Panama, and thus exempt from data retention laws that undermine logging policies. Moreover, they accept Bitcoin payments, so you can really divorce your identity from your traffic online.
Read our full NordVPN review.
2. Surfshark
- Bypass government censorship with NoBorders mode
- Unlimited server switching
- VPN obfuscation on any server with special Camouflage function
- VPN home jurisdiction in British Virgin Islands is ideal for privacy
- Helpful 24/7 live chat with an actual human being
- Speeds occasionally suffer a noticeable drop
- Apps may be too simplistic for power users
Surfshark is another VPN which has done away with outdated protocols in favor of ones which “just work” with modern hardware and privacy solutions. These include OpenVPN, IKEv2/IPSec, WireGuard and Shadowsocks on Windows devices, shrouded in NSA-grade 256-AES-GCM encryption. It’s actually fair to say that these provisions far exceed the security of a standard NAT firewall.
Surfshark breaks other VPN conventions as well, offering unlimited simultaneous connections, bandwidth, server switching, and zero discrimination on traffic type. Each of their 800+ servers in 50 countries is obfuscation-ready, essentially erecting a VPN for your VPN. Their entire network is diskless, meaning they are physically incapable of long-term user metadata storage.
Round it out with a kill switch, IP/DNS/WebRTC leak protection, anti-malware, pop-up blockers and anti-tracking, plus a solid no-logging policy, and you’ve got one of the most secure VPNs on the market.
3. ExpressVPN
- SPECIAL OFFER: 3 months free (49% off – link below)
- Superfast servers (minimal speed loss)
- AES-256 encryption
- Keeps no logs of personal data
- Customer Service (24/7 Chat)
- Priced slightly higher
ExpressVPN is one of the easiest-to-use VPNs, and it offers incredible speeds to users around the world. It starts with a wide network of 3,000+ servers in 94 different countries, enough to ensure you can find a close connection for top speeds and lag-free gaming. You’ll have unlimited bandwidth to enjoy these download speeds as well, along with endless access to P2P networks and torrents, strong 256-bit AES encryption, DNS leak protection, and reliable uptime for the entire network.
ExpressVPN doesn’t specifically advertise a standalone NAT firewall, but there’s a good reason for that. ExpressVPN’s servers have built-in filtering features that reject unrequested packets of data, which keeps out malicious third parties by default.
Read our full ExpressVPN review.
4. IPVanish
If you want to stay safe when you go online, you need to be invisible. IPVanish provides a ton of features that help keep you private and secure when you browse the internet, and it does it all with extremely fast servers with very little lag. If you need anonymous and unrestricted access to torrents or P2P networks, IPVanish will deliver. If you need to bypass censorship blocks or keep your location hidden while you travel, IPVanish will deliver that, too.
To top it all off, the IPVanish network has over 40,000 IP addresses spread across 1,300 servers in 60 different countries, a highly robust offering by any standard that spoils you for choice in optimizing your connection.
IPVanish states up front that it deploys a NAT firewall to help keep malicious connections and data packets at bay. This holds true for every server in its worldwide network.
IPVanish also comes with the following features:
- Lightweight and easy-to-use VPN apps for PC, laptops, smartphones, tablets, and even Chromebooks.
- Unlimited bandwidth, no speed caps, and no restrictions on P2P or torrent traffic.
- Secure, fast, and anonymous downloads ideal for torrent and Kodi users.
- A strict zero-logging policy on all user traffic.
Read our full IPVanish review.
5. PureVPN
PureVPN is a fast, friendly, and privacy-aware VPN service designed to make the internet a safer place for everyone. It starts with strong 256-bit encryption to keep prying eyes away from your data. This is backed by a zero-logging policy that covers all traffic, kill switch and DNS leak protection features, as well as a massive network of over 2,000 servers in 141 countries.
PureVPN owns and operates this entire network themselves, which allows them to customize hardware and software as they please and steer clear of third parties for increased data security.
PureVPN offers a NAT firewall as a paid add-on to its regular service. Once you sign up for the VPN, you can access and enable this feature in the member’s area for a low monthly fee.
PureVPN’s features at a glance:
- Excellent custom apps for all modern operating systems, smartphones, tablets, PCs, and more.
- Advanced features include anti-virus protection, ad-blocking, and anti-phishing measures.
- Self-owned network of servers for enhanced privacy and security.
Read our full PureVPN review.
6. VyprVPN
VyprVPN delivers some of the most unique and most useful privacy features in the VPN marketplace. For starters, the company owns and operates its entire network of servers, over 700 in 70 different countries. This gives them the freedom to upgrade and customize each server to meet their own specifications, and it keeps third parties out of the picture entirely.
VyprVPN also offers its exclusive Chameleon technology for increased anonymity and security. Chameleon scrambles the metadata in encrypted packets to help defeat deep packet inspection, a method commonly used by the Chinese government to block online content. With Chameleon in place, you can access the entirety of the internet without censorship and without giving up your identity.
VyprVPN offers a NAT firewall for all of its VPN plans. The company also stresses the importance of this protection for everyone who uses the internet, especially travelers and smartphone surfers.
VyprVPN also includes the following features:
- Support for desktop operating systems, smartphones, and a variety of other platforms.
- Incredible privacy features for the best VPN access in China and the Middle East.
- Unlimited bandwidth and no restriction on P2P traffic or torrent downloads.
- Zero-logging policy on both traffic and DNS requests.
Read our full VyprVPN review.
Conclusion
At this point, you should have a much clearer understanding of how a NAT firewall works to filter out unauthorized connections and protect your device from malicious attacks. We’ve recommended a few VPN providers which either offer turnkey firewalls built into their software, or which have other novel solutions that offer the same level of protection or better.
What are your main cybersecurity worries? Do you use a configuration other than a VPN to protect yourself? Leave your tips for our readers below.
If you need a VPN for a short while when traveling for example, you can get our top ranked VPN free of charge. NordVPN includes a 30-day money-back guarantee. You will need to pay for the subscription, that’s a fact, but it allows full access for 30 days and then you cancel for a full refund. Their no-questions-asked cancellation policy lives up to its name.
