(IDS) Intrusion Detection Systems/Software

[FusIonX]

I am looking for some good open-source intrusion detection software.

I have found BackTrack which is for testing networks along with Blackbuntu

but I am looking for software that runs on a network on the inside, detecting intrusions on the network.

 

[Kharn]

Snort.

 

[office politics]

http://www.techist.com/forums/f57/network-security-toolkit-sourceforge-project-224986/

includes prebuilt snort