Open source tools can be used to create a defense system for your network that actually works. Tools like Snort/Suricata, Bro, various logs, and PCAP capture and analysis systems can be used to build a network that functions well and won't crush your budget. This talk is non-commercial and includes no FUD, no APT-worthy buzzwords ... no bullshit.
We will discuss common data sources, what they are, how to collect from them and what to do with the data. We will also cover the big picture of network defense and ways to piece together a network security monitoring (NSM) system. Finally, we will explore processes 
that we can go through to use these tools without breaking your budget for either time or money.