Re: IPv4 only apps [was: IPv6 only host NAT64 requirements?]

Brian E Carpenter <> Tue, 14 November 2017 02:11 UTC

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Subject: Re: IPv4 only apps [was: IPv6 only host NAT64 requirements?]
To: Ole Troan <>
Cc: Philip Homburg <>, 6man WG <>
References: <> <> <> <> <> <> <>
From: Brian E Carpenter <>
Organization: University of Auckland
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Date: Tue, 14 Nov 2017 15:11:52 +1300
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On 14/11/2017 14:57, Ole Troan wrote:
> Brian,
> [...]
>>> 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.
>> And that neglects the legacy that most such hosts have inside them.
>> I have a bunch in the host I'm typing on right now, which is connected
>> via NAT64 for the week.
> I don't understand what you mean with the above.
> I guess this is where we have to be extremely careful with terminology use.
> If you are using the IPv6 only + NAT64 network you can't possibly use the legacy IPv4 only stuff in your laptop...?

Indeed. Because my laptop isn't providing a NAT46 bump in the stack, for example.

I haven't analysed this at all. What I'm saying is that we haven't done this;
we've simply sneered at application developers who haven't added IPPROTO_IPV6
to all their network code. Sneering doesn't solve much.

> Cheers,
> Ole