using "reserved" IPv6 space
Mark Andrews
marka at isc.org
Thu Jul 19 04:17:50 UTC 2012
In message <CAAAwwbXn_zfk86YfD9myg6-HcnwSW2pMUQ6yXwpR6B8V4FOVMw at mail.gmail.com>
, Jimmy Hess writes:
> On 7/18/12, Mark Andrews <marka at isc.org> wrote:
> [snip]
> > space, you meet the requirements. Toss a coin for each bit. Heads
> > =3D 1, tails =3D 0.
> Sure... and if someone says they just happened to toss a coin 128
> times, and got "0" all 128 times, therefore legitimately assigned ULA
> ID is all zeros, I don't believe them.
Given it is 40 bits not 128 bits the chance of getting all zero/all ones
is < 0.000000000001%.
> (1 / 2)^128 * ([128 : 128])
>
> for =E1 =3D 0.0000000002
> H_0: fair coin
> Observation: 128 heads out of 128 flips (or 128 tails out of 128 flips)
>
> For H_0, Prob given >=3D 128 heads or >=3D tails =3D 2*(1 - Prob(<1=
> 28) ) =3D
> < 0.000000000000000000000000000000000006%
>
> Reject H_0.
>
>
> Perhaps the world would be well served if the RFC called for routers to app=
> ly
> some [very lenient] randomness tests to the sequence of bits proposed
> to be configured as a ULA ID.... :)
Given there is no such possible test I fail to see how you could
expect anyone to implement it. You can't examine a single value
to determine if it was randomally choosen or not. Even with multiple
values you can't determine if there were randomally or systematically
choosen as there are a inifinite number of systems that will produce
a randomally choosen sequence.
Mark
--
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742 INTERNET: marka at isc.org
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