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ghshephardtoday at 12:30 AM2 repliesview on HN

Just to nitpick a bit. What people typically mean when they say "IPV4 NAT" is Network and Port translation. My 192.168.0.1 internally becomes 172.217.12.100 and my port gets converted to something that is tracked so that the return packet can find it's target.

In IPv6, Prefix-Translation is similar, in that the /64 prefix is translated 1:1 - but the /64 Host address is (in my experience) left alone - so that renumber a network becomes trivial when you change ISPs - you just just change the prefix.

I don't actually know if "IPv4 NAT" behavior even exists in the IPv6 world, except in the form of a lab experiment.


Replies

reincarnate0x14today at 6:03 AM

You can do the many-to-few (or one) NAT behavior with port rewrites in IPv6 if you want to, there are just few circumstances it makes any sense.

FWIW the broad IPv6 network-prefix NAT behavior ALSO EXISTS in IPv4, it's just less applicable.

endmontoday at 1:32 AM

From my understanding, the "IPv4 NAT" equivalent for IPv6 is generally referred to as NAT66 (NPTv6 for Prefix-Translation). For example, Fortinet offers this on their firewalls, and I believe most firewall vendors have this option.

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