Subject: IPv6 concern

From: justin franks <[email-masked]>
Date: Mon, 21 May 2012 18:12:33 -0700

Hello,
I am an Internet Engineer. Specifically large scale ISP and Data Center
networks. I understand we need IPv6 and am working towards that as well.
However, I have major concerns about 2 areas in IPv6
1. The BGP prefix filtering
2. The assignment of multiple /32 or /48's to the same Organization by
various RIR's.
I have typed up a brief one page document here that explains some very
valid points.
http://www.inetassociation.com/ipv6subnetdesign.htm

-Justin Franks

---

From: Jeroen Massar <[email-masked]>
Date: Tue, 22 May 2012 13:56:54 +0200

> http://www.inetassociation.com/ipv6subnetdesign.htm

I do not grasp what you are trying to state with your message as it is
very unstructured.

But a couple of comments to statements in that text:

> Really big organizations and ISP's are given a /32 block.

Actually, per default an ISP will get a /32, really big ones will get
larger blocks, up to /13 have been seen already.

http://www.sixxs.net/tools/grh/dfp/ shows 1 /13 (spread into 14x /22),
2x /19 and several /20's as an example.

> Smaller organizations are given a /48 block

You mean: Organizations who request a PI block and cannot justify more
than a /48.

> Based on those numbers you now know which size prefix you request
> from your RIR. A /48 or a /32.

Or much much much larger, like those /19s mentioned above.

You are obviously forgetting about HD ratio and the amount of customers
that actually are served with these blocks.

"Child Prefixes" are just called subprefixes

> This model is super modular, super simple and super scalable.

It is not, as if you made the wrong choice when chunking up the prefix
you will need to move a little other chunk somewhere else and you will
just end up in routing mess anyway.

> If it was me I would only advertise Child Prefixes from the
> appropriate BGP routers per region.
[...]
> There needs to be an industry standard on what is the smallest prefix
> allowed to be advertised in BGP for IPv6. There is no standard now.
> Once a standard is made then we can begin to plan and design global
> networks accordingly.

Please actually check http://www.space.net/~gert/RIPE/ipv6-filters.html
for current operational practice that has been in use for nearly a
decade already.

You should only expect the assigned-from-RIR block to be accepted,
nothing else, especially not larger announcements.

As such your first concern is because you do not know about current
operational practice. I suggest you follow:
http://lists.cluenet.de/mailman/listinfo/ipv6-ops
and visit RIPE, APNIC, NANOG etc meetings that cover these subjects.

For your second concern, indeed, there are various organizations that
have received a disjunct prefix per RIR and in some cases almost a
disjunct prefix per country. These organizations are typically very very
large though and tend to have disjunct routing policies too.
And you do not want to ship your traffic yourself to the otherside of
the world, it is just too messy, with multiple prefixes all that is solved.

Greets,
 Jeroen