Waste will kill ipv6 too

William Herrin bill at herrin.us
Wed Dec 20 20:57:27 CST 2017

On Wed, Dec 20, 2017 at 1:48 PM, Mel Beckman <mel at beckman.org> wrote:

> I won’t do the math for you, but you’re circumcising the mosquito here. We
> didn’t just increase our usable space by 2 orders of magnitude. It’s
> increased more than 35 orders of magnitude.

Hi Mel,

The gain is just shy of 29 orders of magnitude. 2^128 / 2^32 = 7.9*10^28.

There are 2^128 = 3.4*10^38 IPv6 addresses, but that isn't 38 "orders of
magnitude." Orders of magnitude describes a difference between one thing
and another, in this case the IPv4 and IPv6 address spaces.

Using a /64 for P2P links is no problem, really. Worrying about that is
> like a scuba diver worrying about how many air molecules are surrounding
> the boat on the way out to sea.

It's not a problem, exactly, but it cuts the gain vs. IPv4 from ~29 orders
of magnitude to just 9 orders of magnitude. Your link which needed at most
2 bits of IPv4 address space now consumes 64 bits of IPv6 address space.

Then we do /48s from which the /64s are assigned and we lose another 3 or
so orders of magnitude... Sparsely allocate those /48s for another order of
magnitude. From sparsely allocated ISP blocks for another order of
magnitude. It slips away faster than you might think.

Bill Herrin

William Herrin ................ herrin at dirtside.com  bill at herrin.us
Dirtside Systems ......... Web: <http://www.dirtside.com/>

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