[arin-ppml] IPv6 Non-connected networks

michael.dillon at bt.com michael.dillon at bt.com
Fri Mar 19 11:58:31 EDT 2010

>     michael> As for whois, none of these numbers would be recorded in
>     michael> the RIR whois directories. However, each RIR 
> should operate
>     michael> an instance of the ULA-C directory lookup tool which will
>     michael> query single /48 blocks from the allocation tool's
>     michael> database.  This should not pose any serious problems to
> Are you saying that when I do a whois on this ULA-C, that the 
> server will go do that query for me?

Nope. When you do a whois on a ULA-C address, the server will
send back something like this:

Comment:    These addresses are ULA-C addresses as defined in RFC 7777.
Comment:    These addresses are not intended for use on the public
Comment:    Internet and are not recorded in ARIN's whois directory.
Comment:    However you can query the ULA-C database at
Comment:    Note that ULA-C addresses are assigned randomly. There is
Comment:    no need to check a specific address for availability and
Comment:    ARIN can *NOT* accomodate any requests for a specific block.
Comment:    More information is available at http://ula.arin.net
Comment:    and at http://www.cymru.com/Bogons/ipv6.txt

Now when ARIN allocates fcf8:8f00:40ef::/48 to Thingamiggies Global
and they go to Bill's Bait and Tackle Shop asking him to route this
Bill looks up the whois directory just to be sure, and voila. The whois
directory does *NOT* confirm that this block has indeed been assigned 
to Thingamajiggies, and it more or less tells Bill not to accept this

This doesn't prevent Bill and his friends from plotting to disrupt
the internets by actually routing traffic globally across their ASes
using Thingamajiggies' ULA-C assignment, but then ARIN is not in the 
business of telling Bill and his friends what they can and can't do.
ARIN just won't join the party and make their job easy.

--Michael Dillon

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