Re: using "reserved" IPv6 space

[Mark Andrews <marka () isc org>]

In message <CAAAwwbXn_zfk86YfD9myg6-HcnwSW2pMUQ6yXwpR6B8V4FOVMw () mail gmail com>
, Jimmy Hess writes:
> On 7/18/12, Mark Andrews <marka () 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 () isc org