> Was also designed in the early 90s before security was taken seriously.
True, but since then it has transformed into “no one gets in because we have _private_ IP addresses”…
To be fair it's a pretty decent defense, in the early days of blaster and today with iot crap.
I would need to ask the follow up question. Okay so what happens when someone gets in? Say some idiot install something they should not. Or there is some vulnerability in something you allow in?
Extra layers is good. But it does not mean you can forgo anything else.