Dual stack IPv6 for IPv4 depletion

George Metz george.metz at gmail.com
Tue Jul 14 13:23:17 UTC 2015


That's all well and good Owen, and the math is compelling, but 30 years ago
if you'd told anyone that we'd go through all four billion IPv4 addresses
in anyone's lifetime, they'd have looked at you like you were stark raving
mad. That's what's really got most of the people who want (dare I say more
sane?) more restrictive allocations to be the default concerned; 30 years
ago the math for how long IPv4 would last would have been compelling as
well, which is why we have the entire Class E block just unusable and large
blocks of IP address space that people were handed for no particular reason
than it sounded like a good idea at the time.

It's always easier to be prudent from the get-go than it is to rein in the
insanity at a later date. Just because we can't imagine a world where IPv6
depletion is possible doesn't mean it can't exist, and exist far sooner
than one might expect.

On Tue, Jul 14, 2015 at 12:22 AM, Owen DeLong <owen at delong.com> wrote:

> How so?
>
> There are 8192 /16s in the current /3.
>
> ISPs with that many pops at 5,000,000 end-sites per POP, even assuming 32
> end-sites per person
> can’t really be all that many…
>
>
> 25 POPS at 5,000,000 end-sites each is 125,000,000 end-sites per ISP.
>
> 7,000,000,000 * 32 = 224,000,000,000 / 125,000,000 = 1,792 total /16s
> consumed.
>
> Really, if we burn through all 8,192 of them in less than 50 years and I’m
> still alive
> when we do, I’ll help you promote more restrictive policy to be enacted
> while we
> burn through the second /3. That’ll still leave us 75% of the address
> space to work
> with on that new policy.
>
> If you want to look at places where IPv6 is really getting wasted, let’s
> talk about
> an entire /9 reserved without an RFC to make it usable or it’s partner /9
> with an
> RFC to make it mostly useless, but popular among those few remaining NAT
> fanboys. Together that constitutes 1/256th of the address space cast off to
> waste.
>
> Yeah, I’m not too worried about the ISPs that can legitimately justify a
> /16.
>
> Owen
>
> > On Jul 13, 2015, at 16:16 , Joe Maimon <jmaimon at ttec.com> wrote:
> >
> >
> >
> > Owen DeLong wrote:
> >> JimBob’s ISP can apply to ARIN for a /16
> >
> > Like I said, very possibly not a good thing for the address space.
>
>



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