[yardstick]

You are correct there’s nothing in the core IPv6 spec itself about NAT. However the goal of IPv6 - to make all devices globally reachable - resulted in pretty much everyone not implementing NAT support until way too late in the game. And resulted in related specs required to implement NAT not appearing for years/decade after IPv6 was created.

Linux/Iptables support wasn’t until Linux 3.7 & iptables 1.4.18 [1]. So that’s only from 2013, when IPv4 NAT has been possible for well over a decade before that.

Also to do NAT66 you really need a ULA address space, that wasn’t defined until 2005 [2]. RFC1918 addresses for IPv4 were set in 1996.

The tooling, support code, supporting RFCs, and UIs for doing IPv6 NAT has been neglected. It’s a halfway house.

1. http://tldp.org/HOWTO/Linux+IPv6-HOWTO/ch18s04.html 2. https://tools.ietf.org/html/rfc4193