NAT444 or ?

Douglas Otis dotis at
Fri Sep 2 17:44:59 UTC 2011

On 9/1/11 11:52 AM, Cameron Byrne wrote:
> On Thu, Sep 1, 2011 at 11:36 AM, Serge Vautour<sergevautour at>  wrote:
>> Hello,
>> Things I understand: IPv6 is the long term solution to IPv4 exhaustion. For IPv6 to work correctly, most of the IPv4 content has to be on IPv6. That's not there yet. IPv6 deployment to end users is not trivial (end user support, CPE support, etc...). Translation techniques are generally evil. IPv6->IPv4 still requires 1 IPv4 IP per end user or else you're doing NAT. IPv4->IPv6 (1-1) doesn't solve our main problem of giving users access to the IPv4 Internet.
> Correct, all content is not there yet... but World IPv6 Day showed
> that Google, Facebook, Yahoo, Microsoft and 400+ others are just about
> ready to go.
> IPv6->IPv4 does not require 1 to 1, .... any protocol translation is a
> form of NATish things, and stateful NAT64 has many desirable
> properties IF you already do NAT44.  Specifically, it is nice that
> IPv6 flows bypass the NAT .... and as more content becomes  IPv6, NAT
> becomes less and less used.  In this way, unlike NAT44 or NAT444,
> NAT64 has an exit strategy that ends with proper E2E networking with
> IPv6... the technology and economic incentives push the right way
> (more IPv6...)
> Have a look at
> There are multiple opensource and big vendor (C, J, B, LB guys...)
> implementation of NAT64 / DNS64 ... I have trialed it and plan to
> deploy it, YMMV... It works great for web and email, not so great for
> gaming and Skype.
moves CPE NAT to the ISP tunneled over
>> Has anyone deployed NAT444? Can folks share their experiences? Does it really break this many apps? What other options do we have?
> Yes, expect it to be deployed in places where the access gear can only
> do IPv4 and there is no money or technology available to bring in
> IPv6.
A false economy when support outweigh CPE cost.


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