Sagan is multi-threaded, real-time system- and event-log monitoring software, but with a twist. Sagan uses a "Snort" like rule set for detecting nefarious events happening on your network and/or computer systems. If Sagan detects a "bad thing" happening, it can do a number of things with that information. Sagan can also correlate the events with your Intrusion Detection/Intrusion Prevention (IDS/IPS) system and basically acts like an SIEM (Security Information and Log Management) system.
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