minimum IPv6 announcement size

Tue Oct 1 18:11:23 UTC 2013

On Tue, Oct 1, 2013 at 12:04 PM, Rob Seastrom <rs at seastrom.com> wrote:
> William Herrin <bill at herrin.us> writes:
>> IPv4 jumped from 8 bits to 32 bits. Which when you think about it is
>> the same ratio as jumping from 32 bits to 128 bits.
>
> Jumping from 8 bits to 32 bits (1:16mm) is the same ratio as would be
> jumping from 32 bits to 48 bits (also, 1:16mm).

Hi Rob,

And yet we're allocating /19's where previously we allocated space
that added up to /7's and /48's where previously we allocated /24's.
My math may be flawed but the pattern is there all the same.

> Going from 32 bits to 128 bits is 1:79228162514264337593543950336 which
> is not even remotely the same ratio.

You know enough about IPv6 to realize that we didn't go from 32 bits
to 128 bits, we went from either 24ish bits to 48 or 28ish bits to 64,
depending on how you look at it. While IPv6 is capable of working the
same as IPv4, that's not how we're actually using it.

More, growth has not been linear since IPv4's advent and is not (by
anyone reasonable) projected to be linear or sub-linear in IPv6.
Computing a linear ratio as if that were representative of the
expected lifetime of the new address space does not paint an honest
picture.

> Sorry for the late reply, Bill, but you were snoozing when they taught
> logarithms in high school weren't you?

While I did in fact snooze my way through a significant part of
school, I was wide awake for the word problems where we were asked to
build an appropriate equation. You remember: the trick questions where
a couple of irrelevant bits of data were thrown in and critical
factors were implied without being stated. And despite the
distractions you were asked to grasp the essential problem from the
English language description. Those were fun.

Regards,
Bill Herrin

-- 
William D. Herrin ................ herrin at dirtside.com  bill at herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
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