Re: SixXS ULA Registry clarifications / questions / comments (Was: IPv6 fc00::/7 — Unique local addresses)

Thu Oct 21 11:23:33 UTC 2010

> 
> Is there a problem that one entity has 7 /48's out of (2**(128-8-48))
> possible ones... no I am not going to write out that number or write it
> out in a percentage ;)
> 
Your math is incorrect... It's 2^40, not 2^(128-8-48)

8	fd00::/8 -- preassigned.
40	Randomly generated
16	Locally assigned
64	Host identifieers
----
128

Of that, only the 40 randomly generated provide ULA prefix uniqueness.

Still... 2^40 is ~1 Trillion prefixes. If 7 Billion people all grab 7 prefixes,
that's still only 49 Billion prefixes.

However, since there's no reclamation at death, and, we're not just talking
about people, but, people+orgs+whatever, I can see the potential for
the sixxs registry to get harvested and ULA exhausted in less than
50 years with concerted effort.

However, running out of ULA is, IMHO, the least of our problems with
such a registry and its practices.

> [..]
>> or 458 752 subnets, and http://deticon.net isn't reachable via IPv6
> 
> Maybe because ULA is *LOCAL* address space. For that matter, as a great
> example: you won't find 9.0.0.0/8 easily on the internet either, I can
> tell you though that it is quite heavily used and completely filled up,
> so far even that there are a lot more prefixes that that organization
> uses for other purposes.
> 
He didn't say he couldn't find the prefix on the net. He said he couldn't
find the domain name.

I believe ibm.com is quite easy to find on the internet.

> [..]
>> IPv4 (and hasn't been for quite a while - I checked a few months ago
>> when I discovered the registry), it seems to me that people have
>> already misunderstood what it's purpose is, and that the database is
>> already polluted with invalid entries that can't be verified for
>> existence, and which also can't be expired via some invalidation
>> mechanism, such as lack of payment of annual fees.
> 
> You want us to charge for virtual numbers which don't really exist? :)
> 
It is the only (so far) mechanism anyone has identified for being able
to reliably confirm continued utilization of resources. If you have
some other mechanism, go for it. If not, then you've just created
a whole new class of swamp space and I will point you to the
legacy address issues surrounding these same problems with IPv4
as an example of why this is a bad idea.

> For all entries we have an email address, at the time of registration
> that email address was tested at least as having a proper configuration.
> We could always, if we wanted but I don't see why, start spamming people
> and ask them if their registration data is still correct.
> 
If the domain shown in the record isn't resolvable, it's a pretty good
indication that the email address probably won't work, no?

Deprecating someones registration just because they don't respond
to email is, well, not something people have wanted the RIRs to do,
so, likely SIXXS will have similar problems.

> If you really think that the list is polluted by some entries then don't
> hesitate to mail info at sixxs.net and next to all the other things we do
> we might be able to look into it.
> 
ROFLMAO...

> There really are enough /48's in that /8 for everybody. At this moment
> there are 1024 of them in there, I don't even think there is a
> percentage number for that yet. I don't even think you are able to

1024 is roughly 1/1,000,000,000th of the space. 40 bits is roughly
a trillion.

> generate a single ULA that will clash with one of the entries in the
> list unless you generate a really large amount of them, cause well, that
> is the whole point of the ULA generation algorithm in the first place.
> 
Yep. And the primary reason that ULA is a much worse idea than
RFC-1918.

> As long though as there are this few entries, I really cannot see the
> point for this.
> 
And so they created a new copy of the IPv4 swamp in IPv6 land,
because they could, and, because they could not learn the lessons
of history and were thus doomed to repeat them.
> 
> Please remember that a prefix you get from the RIRs does not have a
> requirement of being announced on the Internet, you can also use it to
> interconnect between your own local networks. This is also the reason
> why fc00::/8 will never be used, as it will be exactly the same as what
> the RIRs are doing today already with 2000::/3.
> 
Exactly, so, why even have this ULA confusion in fd00::/8 to begin with?

Owen