Is the fact that your physical door locks and keys are only unique to your local region very much an implementation detail? No it's not. It's conceptually the same, but keys and locks are not globally secure. They're only locally secure.

Also IPv6: everything gets a globally routable address. Great so why do we need anything else? Well it turns out that in order to support all the different modes of network operation and all the different topologies and use cases, the Internet Protocol needs to support non-global scopes too. Arguing you can't have e.g. link-local security is absurd and rally quite green, from a networking professionals perspective.

Oh also IPSEC is part of IPv6 not just an afterthought like it was for IPv4. This makes it even more likely we'll see trusted network scopes sooner rather than never.

> It's conceptually the same, but keys and locks are not globally secure. They're only locally secure

Criminals in Hong Kong can’t teleport to my door. Local security for locks is fine because the threat is always local.

> Criminals in Hong Kong can’t teleport to my door.

They might be able to hijack a different IoT device on the network. The more IoT devices, the greater the attack surface.

What if you have guests over and they happen to have a bad virus on their computer or their phone?

That is basically my point. People need to have ways to create local enclaves so it's impossible for packets to ever make their way into your zone. And wonxe you do that, local security is perfectly reasonable and desirable.

HTTPS only protects data in transit from the server to your device. A local network work just fine for providing the same protection. It's not like an internet attacker can spoof a 192.168.x.x address on my LAN, or sniff the traffic to or from my server.

Possibly a rogue IoT device could spoof an ip address. But that's probably not going to happen to someone who knows what they're doing. Browsers don't know if the network is trusted and can't assume that LAN IPs are safe.

It seems to me the best options are either trusting a self-signed cert (on every computer that needs access) or pay for a domain name and use letsencrypt to get a cert. I do think it's unfortunate that you now need to pay money just to do things like this on your own network, but I don't see a better way. It's either paying for a domain name or needing to explicitly trust the device.