Snort - network intrusion prevention system

Ima kdo izkušnje s tem programom? Pripravljam se na začetek izdelave diplomske naloge, pa bom za testiranje potreboval kvaliteten "network intrusion prevention system" program. Obstaja še kak spodoben brezplačen program?
Za analizo že imam Wireshark.
Morda pozna kdo dober program za načrtovanje IP omrežij? (Nekaj v stilu COMNET III.)

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1. What is Snort?
Snort is an open source network intrusion prevention system, capable of performing real-time traffic analysis and packet logging on IP networks. It 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.
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Hvala.