Open Source / Low cost Intrusion detection software

[lundrog]

I am looking for Open Source / Low cost Intrusion detection software

I am looking for something that sits after the main firewall, but before the network.

Like, do they make anything that makes a fake network after your firewall but before your network?

Basically, something that reports and alerts, and blocks any ( intrusive activity )


Thanks

 

[LittleMe]

You could have put this in your other thread about network monitoring but regardless, look into Snort