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

Jimmy Hess mysidia at
Sat Jan 19 22:15:06 UTC 2013

On 1/18/13, David Swafford <david at> wrote:
> There is no "suckerage" to V6.   Really, it's not that hard.  While
> CGN is the reality, we need to keep focused on the ultimate goal -- a

Correct.  CGN may be part of a transition towards IPv6.    Not all
providers are necessarily going to see it that way.   It's a
non-resolutely answered question, whether IPv4+CGN will win,   and it
will become the new common delivery of IP, or if IPv6 will win.

What will be the ultimate cost,  for a provider choosing to implement
only IPv4 CGN, and completely eschew/ignore IPv6,  if IPv6, gets
massive buy-in  and becomes a predominant IP networking technology,
in demand,  adopted by all their competitors....
Potential loss of much business for the service provider, due to
competitive disadvantage.

Versus cost of careful design and building in IPv6   together with CGN
rollouts,   so there
is one    major redesign,  to prepare for  transition, and not two
separate rollouts
one for CGN and one later to completely rethink for IPv6...

In either scenario....  1 ISP network implementation project for 1
wrong technology for dealing with IP exhaustion (IPv6 or CGN),  and
not recognizing the problem early is a disaster  -- business goes to
the competition.

2 ISP network implementation projects;  first 1 technology, then the
other, after discovering, the wrong technology was chosen,   is  an
improvement (but still expensive)  --   network redesign is time
consuming,  network devices and software are expensive,  and business
lost to the competition,  at least until redesign is completed.

1 implementation  of 1 right technology (IPv6 or CGN) and never the
other  is ideal -- cost implementing CGN (or IPv6) is avoided,  if
the technology never became necessary.    (It's an unlikely scenario
after IP exhaustion,  however,  that either will be unnecessary.)

1 up front preparation/implementation of 2 technologies,  in time for
IP exhaustion,  has high upfront cost, but alleviates  the high risk
of the first 2 scenarios.

> single long term solution.  Imagine a day where there is no dual
> stack, no IPv4, and no more band-aids.   It will be amazing.

It's  probably about  20 years away.

> david.

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