Internet connection Firewall
Windows XP comes with a firewall known as the Internet Connection Firewall or ICF. ICF provides only inbound protection-unlike a full-fledged firewall, it only monitors incoming data. To turn on ICF, go to the Control panel and select Network Connections. Right-click on the displayed connection, and click on Properties. Under the Advanced tab, you can enable ICF. While the default settings may work fine, you may want to tweak the settings. Click on the Settings button to access all the ICF features and settings. You can fine tune the network services under the Services tab, set logging details under Security Logging, and details about ICMP under the ICMP (Internet Control Message Protocol) tab.
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