using "reserved" IPv6 space

Stephen Sprunk stephen at
Wed Jul 18 13:47:57 UTC 2012

On 18-Jul-12 08:25, Saku Ytti wrote:
> On (2012-07-18 09:10 -0400), valdis.kletnieks at wrote:
>> You want to roll in at some entropy by adding in the current date or something, so two "Joes' Burritos and Internet" in 2 different states don't generate the same value.  There's a reason that 4193 recommends a 64bit timestamp and an EUI64.
> I assume business ids are federal not state, as IRS is federal? Anyhow I'm not saying 'this is how it should be done', I'm saying maybe there is way to do this in a way which is verifiably random.

US EINs/SSNs, and various state-level ID numbers, are not random; given
our problems with identity theft, they're not guaranteed to be unique,
either.  I assume the same is true for identification numbers in most
other countries.

> 64b timestamp and EUI64 make it non-verifiable.

If you publish the numbers you used, then others can verify that those
values are reasonable.  I doubt anyone would sift through billions of
reasonable timestamps combined with the thousands of EUI64s at their
site just to find a result that was "memorable".

And, if they did, who cares?  It's not like it hurts me for them to do
so--unless I'm dumb enough to do the same thing, happened to get the
same result /and/ happened to merge with them--all of which are still
unlikely events.


Stephen Sprunk         "God does not play dice."  --Albert Einstein
CCIE #3723         "God is an inveterate gambler, and He throws the
K5SSS        dice at every possible opportunity." --Stephen Hawking

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