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minimum IPv6 announcement size
Yup. Seen/Heard all that. Even tooted that horn for a while.
/64 is an artifical boundary - many/most IANA/RIR delegations are in the top /32
which is functionally the same as handing out traditional /16s. Some RIR client
are "bigger" and demand more, so they get the v6 equvalent of /14s or smaller.
Its the _exact_ same model as v4 in the previous decade. With the entire waste
in the bottom /64.
Its tilting at windmills, but most of the community has "drunk the koolaide"
on wasteful /v6 assignment. What a horrific legacy to hand to our children
(and yes, it will hit that soon)
/bill
On Thu, Sep 26, 2013 at 01:18:50PM -0700, Darren Pilgrim wrote:
> On 9/26/2013 1:07 PM, joel jaeggli wrote:
> >
> >On Sep 26, 2013, at 12:29 PM, Darren Pilgrim <nanog at bitfreak.org>
> >wrote:
> >
> >>On 9/26/2013 1:52 AM, bmanning at vacation.karoshi.com wrote:
> >>>sounds just like folks in 1985, talking about IPv4...
> >>
> >>The foundation of that, though, was ignorance of address space
> >>exhaustion. IPv4's address space was too small for such large
> >>thinking.
> >
> >The first dicussion I could find about ipv4 runnout in email
> >archives is circa 1983
> >
> >>IPv6 is far beyond enough to use such allocation policies.
> >
> >There are certain tendencies towards profligacy that might
> >prematurely influence the question of ipv6 exhaustion and we should
> >be on guard against them allocating enough /48s as part of direct
> >assignments is probably not one of them.
>
> That's just it, I really don't think we actually have an exhaustion risk
> with IPv6. IPv6 is massive beyond massive. Let me explain.
>
> We have this idea of the "/64 boundary". All those nifty automatic
> addressing things rely on it. We now have two generations of hardware
> and software that would more or less break if we did away with it. In
> essence, we've translated an IPv4 /32 into an IPv6 /64. Not great, but
> still quite large.
>
> Current science says Earth can support ten billion humans. If we let
> the humans proliferate to three times the theoretical upper limit for
> Earth's population, a /64 for each human would be at about a /35's worth
> of /64's. If we're generous with Earth's carrying capacity, a /36.
>
> If we handed out /48's instead so each human could give a /64 to each of
> their devices, it would all fit in a single /52. Those /48's would
> number existance at a rate of one /64 per human, one /64 per device, and
> a 65535:1 device:human ratio. That means we could allocate 4000::/3
> just for Earth humans and devices and never need another block for that
> purpose.
>
> That's assuming a very high utilisation ratio, of course, but really no
> worse than IPv4 is currently. The problem isn't allocation density, but
> router hardware. We need room for route aggregation and other means of
> compartmentalisation. Is a 10% utilisation rate sparse enough? At 10%
> utilisation, keeping the allocations to just 4000::/3, we'd need less
> than a single /60 for all those /48's. If 10% isn't enough, we can go
> quite a bit farther:
>
> - 1% utilisation would fit all those /48's into a /62.
> - A full /64 of those /48's would be 0.2% utilisation.
> - 0.1%? We'd have to steal a bit and hand out /47's instead.
> - /47 is ugly. At /52, we'd get .024% (one per 4096).
>
> That's while maintaining a practice of one /64 per human or device with
> 65535 devices per human. Introduce one /64 per subnet and sub-ppm
> utilisation is possible. That would be giving a site a /44 and them
> only ever using the ::/64 of it.
>
> Even with sloppy, sparse allocation policies and allowing limitless
> human and device population growth, we very likely can not exhaust IPv6.