[takeda]

Interrent would be very different (better) today if not for NAT.

NAT restricts what is possible to do over network for example we only use TCP and UDP protocols, because those protocols are supported by most devices. Similarly we have very minimal number of peer to peer applications. P2P currently is mostly popular with piracy, but it could be beneficial for other uses.

NAT + asymmetric speeds (which started because of DSL, but ISPs decided to keep things that way even though it is no longer necessary) are responsible that's why we haven't a lot of services that are centralized. IPv6 has chance to fix this and I am so glad NAT wasn't included in its design.