> I think this software-only post is meant for IP cameras / surveillance cameras. Internet is the oposite of closed circuit.

I think in this case, IP is referring to IP from TCP/IP, meaning "The Internet Protocol", not necessarily over/through "public internet links", so as long as you're only within your own local network/WAN, wouldn't that still be CCTV then? Or maybe the "closed circuit" thing is more of a physical property than I read it to be?

I'm also non-native English speaker FWIW.