5 Best Open Source Firewall Distributions

Security is paramount. Security involves defense in depth. Approaching security one step at a time, with consistency and rigour, you can mitigate threats, and keep intruders at bay.

Intruders use a variety of different techniques in an attempt to compromise a system. For example, systems can be attacked by denial of service, cracking, intrusion, snooping (intercepting the data of another user), or viruses/worms/Trojan horses. To have a secure box, a system therefore needs a variety of defenses.

One important step to protect a system is using a firewall. Essentially, this is a network security system, acting like a security guard between internal and external networks. The firewall controls incoming and outgoing network traffic using security rules. The rules specify which connections you want to allow and the ports and zones through which the connection can be established.

Here’s our verdict captured in a legendary LinuxLinks chart. All of the software featured in this article is released under an open source license. Each of the solutions offer a comparable set of features to many expensive commercial firewall solutions.

Let’s explore the 5 firewall distros at hand. For each distro we have compiled its own portal page, a full description with an in-depth analysis of its features, together with links to relevant resources.

This article has been revamped in line with our recent announcement.

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