I apologize for this n00b question, but I'm trying to learn networking to help at a non-profit where the old IT guy is no longer there. They have several Cisco switches and one pfSense instance that controls the network. I have a basic idea of how certain things work (a few VLANs, a DMZ), but there is a basic thing I don't get: how does it control all the network traffic?
I see a bunch of different sets of firewall rules, but how exactly are they applied if the pfSense box is just another networking device plugged into the switch?
Again, it's certainly very simple, but I missed something in all the Youtube videos I've been watching.