Slashdot: UK ISP PlusNet Testing Carrier-Grade NAT Instead of IPv6

Lee Howard Lee at
Fri Jan 18 18:28:37 UTC 2013

On 1/18/13 12:48 PM, "Joe Maimon" <jmaimon at> wrote:

>Lee Howard wrote:
>> You are welcome to deploy it if you choose to.
>> Part of the reason I'm arguing against it is that if everyone deploys
>> then everyone has to deploy it.  If it is seen as an alternative to IPv6
>> by some, then others' deployment of IPv6 is made less useful: network
>> effect.  Also, spending money on CGN seems misguided; if you agree that
>> you're going to deploy IPv6 anyway, why spend the money for IPv6 *and
>> also* for CGN?
>> Lee
>Suppose a provider fully deploys v6, they will still need CGN so long as
>they have customers who want to access the v4 internet.

Not necessarily.  Maybe they need CGN, but they need NAT64, not NAT44.  Or
Or maybe they should just hold their noses and buy addresses for a year or
a few.
What they need a transition strategy; it doesn't necessarily have to be

Years ago, I asked, "Why are we stuck with NAT?"  I still ask that.  I
believe that the reason we're stuck with it is that so many of us believe
we're stuck with it--we're resigned to failure, so we don't do anything
about it.
One of the largest problems we have with this transition is that no one
believes they have any influence on it:  "I'm stuck with IPv4 until every
single other host on the Internet is using IPv6, and maybe for a while
after that, depending on happy eyeballs."
There are many levers of influence, but the most important ones to use are
those that shift externalities.  The cost in transition, either in IPv6 or
in CGN (or both) will be incurred disproportionately by ISPs.  Content
providers who care most about quality experience (and usefulness of IP
address information) now support IPv6.  If you think creatively, you might
come up with several levers that could shift the expense from "it's up to
ISPs to translate" to "content and devices manufacturer businesses are at
risk if they don't support IPv6."

Then there's the question--how do you know when you're done?  Every single
host on the Internet is running IPv6?  All but 100?  A million? A billion?
Probably somewhere in between, but each operator has to decide.  Everyone
else has to decide when to support IPv6--and hope it's before operators
call the transition complete, because then it's too late, because
consumers will choose the competitor's product or service that works (on
IPv6).  If Wordpress doesn't work because there's no IPv6, but Blogspot
and Blogger do, maybe consumers just switch.


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