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Re: IPv6 end user addressing
From: Mark Andrews <marka () isc org>
Date: Thu, 11 Aug 2011 10:40:52 +1000

In message <CAPWAtbJ0kgzAbCjUGvBCE3_njawMDu3AZqLi3JQV4ZP6ivX5KA () mail gmail com>
, Jeff Wheeler writes:
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? =A0If 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

No.  A typical user has 10 to 20 addresses NAT'd to one public address.
My household has

        * game consoles
        * laptops
        * desktops
        * cell phones
        * voip phones
        * printers

all connected to the net.  It doesn't yet have a media server but otherwise
it is pretty typical.

Someday, I expect the pantry to have a barcode reader on it connected back
a computer setup for the kitchen someday.  Most of us already use barcode
readers when we shop so its not a big step to home use.

Just about anything with fireware in it will eventually connect to the net.

The typical household already has 1 or 2 subnets.

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.

Housholds can get as much internal addressing as they need today and as
many nets as they need today with RFC1918.  10/8 broken up into
to /24 is equivalent to a /48 broken up into /64s.

A /56 is equivalent to 192.168/16 broken up into its class C's.
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.

There was a concious decision made a decade and a half ago to got to
128 bits instead of 64 bits and give each subnet 64 bits so we would
never have to worry about the size of a subnet again.  IPv6 is about
managing networks not managing addresses.
Jeff S Wheeler <jsw () inconcepts biz>
Sr Network Operator=A0 /=A0 Innovative Network Concepts

Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka () isc org

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