Power over Ethernet (PoE) basics and beyond

PoE is awesome. My custom home security system is all CCTV PoE with a gstreamer backend running on four-core fanless linux box. Way to go. Complete control. No batteries, no wares spying on me, no personal data getting scraped by big guys. (Cloud connectivity sucks because I have segmented mp4s and jogging through them hurts but I only care for events after they happen, not while they happen.)

Got any recommendations on what cameras to get? The market is absolutely flooded with cheap shitty cloud-connected all-in-one cameras making it hard to find good, simple products.

The cheapest (~15 USD bullet, 20 USD dome) PoE cameras on AliExpress (focal length is pretty much the most important parameter to look at, depending on the fov you want) hooked up to a Unifi NVR. Skip all the vendor manuals, setup steps, and apps - adopt them directly to Unifi Protect.

I put them on separate vlan where they get no outbound network connectivity.

For cases where you want things like facial detection or license plate detection (automatic doors/gates) get a Unifi AI though and those things cost, but for normal perimeter/room monitoring the cheap ones are very good