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Re: IPv6 end user addressing
From: Jeff Wheeler <jsw () inconcepts biz>
Date: Wed, 10 Aug 2011 19:53:56 -0400

On Wed, Aug 10, 2011 at 7:12 PM, Owen DeLong <owen () delong com> wrote:
Is it true that there is no existing work on this?  If that is the
case, why would we not try to steer any such future work in such a way
that it can manage to do what the end-user wants without requiring a
/48 in their home?

No, it is not true.

Can you give any example of a product, or on-going work?  I have read
two posts from you today saying that something either exists already,
or is being worked on.  I haven't read this anywhere else.

I suppose that limiting enough households to too small an allocation
will have that effect. I would rather we steer the internet deployment
towards liberal enough allocations to avoid such disability for the

Have we learned nothing from the way NAT shaped the (lack of)
innovation in the home?

I am afraid we may not have learned from exhausting IPv4.  If I may
use the Hurricane Electric tunnel broker as an example again,
supposing that is an independent service with no relation to your
hosting, transit, etc. operations, it can justify a /24 allocation
immediately under 2011-3, without even relying on growth projections.
That's a middle ground figure that we can all live with, but it is
based on you serving (at this moment) only 8000 tunnels at your
busiest tunnel gateway.  If your tunnel gateways could serve 12,288 +
1 users each, then your /24 justification grows to a /20.  So you
would have a pretty significant chunk of the available IPv6 address
space for a fairly small number of end-users -- about 72,543 at

It isn't hard to do some arithmetic and guess that if every household
in the world had IPv6 connectivity from a relatively low-density
service like the above example, we would still only burn through about
3% of the IPv6 address space on end-users (nothing said about server
farms, etc. here) but what does bother me is that the typical end-user
today has one, single IP address; and now we will be issuing them 2^16
subnets; yet it is not too hard to imagine a future where the global
IPv6 address pool becomes constrained due to service-provider

I would like to have innovations in SOHO devices, too; who knows what
these may be.  But I fear we may repeat the mistake that caused NAT to
be a necessity in IPv4 -- exhausting address space -- by foolishly
assuming that every household is going to need twenty-four orders of
magnitude more public addresses than it has today.

That is what these practices do -- they literally give end-users
twenty-four orders of magnitude more addresses, while it is easy to
imagine that we will come within one order of magnitude of running
completely out of IPv6 addresses for issuing to service providers.

I didn't know what the digit "1" followed by twenty-four zeroes was
called.  I had to look it up.  So our end-users will be receiving
about one-Septillion addresses to use in their home, but no one seems
to be asking what future technology we may be harming by possibly
constraining the global address pool.

Jeff S Wheeler <jsw () inconcepts biz>
Sr Network Operator  /  Innovative Network Concepts

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