[saywatnow]

> This is without considering the false sense of security that address masquerading provides; I cannot recall how many times I’ve heard people say that (gasp!) NAT was fundamental piece in the security of their internal networks (it’s not).

It bugs me when this dogma gets repeated without further explanation, /particularly in the case of IPv6/. No, NAT probably doesn't provide as much security as you think it does, but it does provide benefits. A NAT network is a default-deny-incoming network that cannot fail open, protecting against common boundary firewall configuration errors. A small (but once very pervasive) class of firewall bypass attacks (fragmentation) is eliminated. Obscuring information about the number of devices, and especially (IPv6) their vendors is beneficial. When (inevitably) a bug in your firewall is discovered by bad guys, the presence of NAT limits the kinds of attacks they can make. In the world of IoT, These Things Matter.

It's commonly phrased "NAT is not a security feature, firewalls are", which is midly nonsensical as NAT is a firewall feature .. one which often improves the security posture of the network. Of course there are places you absolutely don't want NAT, but I think it still belongs between the internet and most networks made entirely of desktop, IoT & personal devices.

[maccam94]

> I think it still belongs between the internet and most networks made entirely of desktop, IoT & personal devices.

I think your belief has been shaped by the fact that adoption of P2P protocols was hampered by NAT for over a decade, and that developers often write software that trusts the local network. Default deny policies help protect insecure servers for the time being, but I'd like to see servers that utilize encryption and authentication instead of relying on simple allow all/disallow all firewall policies at the connection level.

[saywatnow]

> developers often write software that trusts the local network

Yes, this is still a source of problems - DNS rebinding allowing websites to attack random sockets on LAN and localhost makes my skin crawl. That the protections are being implemented in the browser makes me sad.

> I'd like to see servers that utilize encryption and authentication

Me, I'd prefer architectural solutions further down the stack than /every single service/ that happens to benefit from a TCP control socket having to duplicate the work of encryption + authentication, with the attendant myriad opportunities for it to go horribly wrong. I already mentioned IoT and we know exactly what that's like when it comes to protecting itself.

Yes, I know, pipe dream .. and going off topic .. but I can wish.