When Windows XP was originally shipped in October 2001, it included a limited firewall called "Internet Connection Firewall". It was disabled by default due to concerns with backward compatibility, and the configuration screens were buried away in network configuration screens that many users never looked at. As a result, it was rarely used. In mid-2003, the Blaster worm attacked a large number of Windows machines, taking advantage of flaws in the RPC Windows service[1]. Several months later, the Sasser worm would do something similar. The ongoing prevalence of these worms through 2004 would result in unpatched machines being infected within a matter of minutes[2]. Because of these incidents, as well as other criticisms that Microsoft was not being proactive in protecting customers from threats, Microsoft decided to significantly improve both the functionality and the interface of Windows XP's built-in firewall, and rebrand it as, simply, "Windows Firewall".

Windows Firewall was first introduced as part of Windows XP Service Pack 2. Every type of network connection, whether it is wired, wireless, VPN, or even Firewire, has the firewall enabled by default, with some built-in exceptions to allow connections from machines on the local network. It also fixed a problem whereby the firewall policies would not be enabled on a network connection until several seconds after the connection itself was created, thereby creating a window of vulnerability.[3] A number of additions were made to Group Policy, so that Windows system administrators could configure the Windows Firewall product on a company-wide level.


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Understanding Windows Firewall

Windows Firewall, previously known as Internet Connection Firewall or ICF, is a protective boundary that monitors and restricts information that travels between your computer and a network or the Internet. This provides a line of defense against someone who might try to access your computer from outside the Windows Firewall without your permission.

If you're running Windows XP Service Pack 2 (SP2), Windows Firewall is turned on by default. However, some computer manufacturers and network administrators might turn it off.

To open Windows Firewall

1.Click Start and then click Control Panel.

2.In the control panel, click Windows Security Center.

3.Click Windows Firewall.



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