Re: IPv6 only host NAT64 requirements?

Ole Troan <> Tue, 14 November 2017 00:38 UTC

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Subject: Re: IPv6 only host NAT64 requirements?
Date: Tue, 14 Nov 2017 08:37:40 +0800
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Cc: Philip Homburg <>, 6man WG <>
To: Brian E Carpenter <>
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> ...
>> But for host software there is a lot more incentive to support dual stack then
>> to do the extra step for NAT64.
>> The big problem I see for NAT64 is that for old IPv4-only applications you
>> have to make two fundamental changes to the application. The first to
>> make sure that the application handles IPv6 in every possible way. And a
>> second pass that makes sure that every place where an IPv4 address literal
>> is handled, works with NAT64.
>> For an application writer it is better to try to avoid doing the second pass.
> I think there is a missing document, and it may well belong in v6ops not
> 6man: "IPv4 Applications on an IPv6-only Host".

IPv4 applications do not run on an IPv6 only host, so that's a short document.

> Your text above is probably a good summary of what the document needs
> to cover. (I also suspect that if this document existed, we wouldn't need
> Jordi's draft attempting to define "IPv6-only".)

Please take that to a different thread. This thread is about a IPv6 only, single stack host connecting to an IPv6 only network.
With a backdoor to the IPv4 Internet for legacy destinations.