Re: IPv6 only host NAT64 requirements?

Philip Homburg <> Mon, 13 November 2017 23:08 UTC

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Cc: Mark Andrews <>
Subject: Re: IPv6 only host NAT64 requirements?
From: Philip Homburg <>
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In-reply-to: Your message of "Tue, 14 Nov 2017 09:46:10 +1100 ." <>
Date: Tue, 14 Nov 2017 00:08:26 +0100
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> Is there any reason to
> run DNS64 at all these days? can be a preconfigured
> zone which allows CLAT to get its mapping.  All the phones have
> CLAT support.  Can we just make DNS64 historic and let the phones
> run all IPv4 connections through CLAT rather than having to stuff
> up DNSSEC and have IPv6 connections terminate in IPv4 servers
> without the application knowing?

If NAT64 was limited to 3GPP interfaces then not a lot of people would care.

The problem started when a vocal group tried to push NAT64 as a general
purpose mechanism for providing IPv4 access.

In that context, there are lots of devices that do implement IPv6, but
do not implement CLAT.

So without DNS64 those devices would lose access to the IPv4 internet.

If you are willing have a stateful NAT box in your network, and requiring
host changes is acceptable, then ds lite is in interesting alternative. 
One that avoids having a NAT function on the host.