Comodo Firewall Editor's Review

There's an old analogy among techies that a firewall is like a bouncer at a nightclub that physically blocks unwanted software from accessing your machine. Comodo Firewall takes things a step further by apeing the adage that "if your name's not on the list, you're not coming in."

A lot of computer security software works on a blacklist system, meaning that programs or websites trying to access the machine are checked against a list of known threats and blocked if they are on the list. It works smoothly, but struggles with so-called zero day attacks: incidents where hackers exploit a security loophole in an application before the application's creators are even aware the loophole exists.

Comodo works on a whitelist system. That means it checks every file or application against a list of 15 million known to be safe. If something isn't on the list, it warns you of a risk and asks you to confirm you want to go ahead. This does mean you get more security alerts than with your average firewall, though in most cases this won't be a significant distraction.

For added protection you can set the software to ask for permission everytime a program tries to change your registry settings, though this is largely replicating the User Account Control system that's built into Windows.

Pros: Extreme level of security for a free application.

Cons: Slightly more interruptions.

Conclusions: Worth trying out to see if you can live with the inevitable false alarms.