Problems with removing NAT from a network

Cameron Byrne cb.list6 at
Wed Jan 5 22:47:26 CST 2011

On Wed, Jan 5, 2011 at 8:31 PM, Mark Andrews <marka at> wrote:
> In message <AANLkTimkgPYKY_AkA5px4-ca-3=oufhGbnenRkPmpTE1 at>, Came
> ron Byrne writes:
>> On Wed, Jan 5, 2011 at 6:42 PM, Dobbins, Roland <rdobbins at> wrote:
>> >
>> > On Jan 6, 2011, at 9:38 AM, ML wrote:
>> >
>> >> At least not without some painful rebuilds of criticals systems which ha=
>> ve these IPs deeply embedded in their configs.
>> >
>> > They shouldn't be using IP addresses in configs, they should be using DNS=
>>  names. =A0Time to bite the bullet and get this fixed prior to their eventu=
>> al forced migration to IPv6.
>> >
>> Somebody should tell the about this being a bad practice,
>> many of their images are linked to ip addresses directly and will
>> certainly fail in the future (this year, mobile) networks that will
>> use NAT64/DNS64.  I am sure users will find other places to view their
>> news when fails to work in these ipv6-only networks.
> Which is one of the reasons why DS-lite is a better solution for
> providing legacy access to the IPv4 Internet than NAT64/DNS64.
> DS-lite only breaks what NAT44 breaks.  DS-lite doesn't break new
> things.

Thanks for the tip.  But, there are legitimate business reason in
various different types of networks for various strategies, thanks for
plugging the one your organization makes.  I am tired of the IPv6
transition flavor of the day war.  The reality for content folks is
that there will be IPv4 host, IPv6 hosts, and dual stack hosts.
Content needs to be dual-stack to reach everyone the best way
(native), but if they lack dual-stack and they use IPv4 literals, they
are going to lose eyeballs. End of story.

Content folks-- do yourself a favor and follow Roland's advice (also
in RFC 1958) and don't use address literals, use names.

And, you will notice that the list at shows only a few web site,
because there are only a few that have this design flaws.  If you know
others, strengthen your case  and add them to the list so that all
parties can benefit.  Otherwise, it is just a few poorly designed
internet services that will be in a rush to fix services when users
complain.... or there web pages hits start trending down while their
competitors trend up.


>> Small summary of the problem of IPv4 literals and how they will break
>> in certain IPv6 environments that will be deployed this year
>> Cameron
>> =3D=3D=3D=3D=3D=3D=3D=3D=3D
>> =3D=3D=3D=3D=3D=3D=3D=3D=3D
>> > ------------------------------------------------------------------------
>> > Roland Dobbins <rdobbins at> // <>
>> >
>> > Most software today is very much like an Egyptian pyramid, with millions
>> > of bricks piled on top of each other, with no structural integrity, but
>> > just done by brute force and thousands of slaves.
>> >
>> > =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0-- Alan Kay
>> >
>> >
>> >
> --
> Mark Andrews, ISC
> 1 Seymour St., Dundas Valley, NSW 2117, Australia
> PHONE: +61 2 9871 4742                 INTERNET: marka at

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