snort -- Open Source network intrusion detection system<hr>
<a href="http://www.snort.org/">http://www.snort.org/</a><hr>
Snort is a libpcap-based packet sniffer/logger which can be used as a
lightweight network intrusion detection system.  It features rules based
logging and can perform protocol analysis, content searching/matching
and can be used to detect a variety of attacks and probes, such as buffer
overflows, stealth port scans, CGI attacks, SMB probes, OS fingerprinting
attempts, and much more.

Snort has a real-time alerting capabilty, with alerts being sent to
syslog, a seperate "alert" file, or as a WinPopup message via Samba's
smbclient

This package has no database support.
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