What is a Windows Firewall?

Windows Firewall is a Microsoft Windows application that filters information coming to your system from the Internet and blocking potentially harmful programs. The software blocks most programs from communicating through the firewall. Users simply add a program to the list of allowed programs to allow it to communicate through the firewall. When using a public network, Windows Firewall can also secure the system by blocking all unsolicited attempts to connect to your computer.

Windows Firewall is a stateful firewall that comes installed with most modern versions of Windows by default. On Windows 2008 Server machines, the firewall is enabled by default, blocking many of the ports that cause so much trouble in otherwise unprotected Windows systems. On virtual servers, the Windows Firewall ensures that only the services necessary for the chosen function are exposed (the firewall will automatically configure itself for new server roles, for instance, and when certain server applications are installed). As members of your domain, the Windows Firewall of your virtual servers can be managed remotely, or through Group Policy.

Customization and Configuration of Windows Firewall

Windows Firewall gives you the ability to configure and customize it based on business (work) and personal (home) needs. Because Windows Firewall turns itself on by default and blocks all incoming traffic, you will need to configure it to fit your needs to be sure that it doesn’t conflict with business applications. You can customize firewall setting and configure exceptions by accessing Windows Firewall in the Control Panel. Windows Firewall allows you to add ports to manually allow incoming traffic from other networks. Properly configuring Windows Firewall can prevent malicious attacks on all computers on your network, reports the Microsoft Corporation.

Reasons Why the Windows Firewall is One of the Best Firewalls

1. The Windows Firewall Offers the Best Integration With Windows

The Windows Firewall is part of the Windows operating system and that goes a long way into providing great protection with little hassle from the user’s part. When you connect to a new network, Windows asks you to set a profile for it (whether you want to turn on sharing or not, etc ).

2. The Windows Firewall Leaks Very Little Information

When testing internet security suites, we run several scans with products like Nessus and Nmap, to see much information each firewall leaks. In all our tests, the Windows Firewall had some of the best results.

3. The Windows Firewall is Very Quiet

The Windows Firewall comes with a long list of default rules that get applied, depending on the profile you set for your network connection. This list is very comprehensive and very little input is required from the user’s part.

4. The Windows Firewall is so Good that Commercial Software Piggybacks on It

The Windows Firewall is so good and so tightly integrated into Windows, that some commercial vendors decided to piggyback on it and use it in their security products. For example, products like Trend Micro Titanium Internet Security or F-Secure Internet Security no longer provide their proprietary firewall modules but use the Windows Firewall instead. They only add anti-malware protection modules or parental controls in their security suites.


The Windows Firewall is a silent tool that keeps our systems safe from all kinds of network threats and has been included in each version of Windows for the last decade. Because it is a silent ally, doing most of its work in the background, few users interact with it on a regular basis, and even fewer know what this tool is and how it works.