[arin-ppml] Advisory Council seeks additional commentary on PP-158

Owen DeLong owen at delong.com
Sat Nov 12 12:50:51 EST 2011

On Nov 11, 2011, at 9:01 PM, William Herrin wrote:

> On Fri, Nov 11, 2011 at 6:27 PM, David Farmer <farmer at umn.edu> wrote:
>> I believe the thread in question starts with this email;
>> http://lists.arin.net/pipermail/arin-ppml/2011-September/023235.html
>> However, do you believe this is something we should be working on?
>> If so, then is this text useful to start working with?
> Hi David,
> What does Richard Steenbergen think? If he continues to see this as an
> issue worth addressing, I'd roll with it for a while and see what sort
> of response there is to docketed draft policy text.
> Reading Richard's note, I think he's saying: the MDN policy would work
> better and be more useful if ARIN simply accepts a registrant's
> determination that a particular set of networks should be constructed
> discretely from each other as opposed to ARIN determining whether the
> need to do so is "compelling."
> So, game it. Two identical sets of, let's say ten discrete networks as
> discrete networks are defined. In one set ARIN assigns 10 distinct
> address blocks based on the registrant's determination that the
> networks are discrete. For the other set, ARIN determines there is no
> compelling need and assigns a single address block for the registrant
> to split among them as desired. In both cases we assume that no fraud
> has occurred: the networks are in fact distinct.
> Questions:
> Are there any parameters for this game in which the registrant
> acquires more IP addresses via the 10 distinct blocks? How much more?

In general, the initial assignment will not be where this policy makes a
significant difference, but, instead, when the applicant runs out of space
in region G while A, B, C, D, E, F, H, I, and J still have space available.

In the non-discrete case, the applicant would be expected to move space
from one of the other regions into G to accommodate the need. In the
discrete case, the applicant is able to apply for an additional prefix for
region G separate from his utilization in the other regions.

> Are there any parameters where more routes must be announced due to 10
> distinct blocks? Remember, genuine distinct networks here, the
> separation can be needless but there is no overt fraud. What about
> parameters which leave no choice but for the single aggregate approach
> to introduce more routes?

If the networks have separate routing policies, it will require a minimum of
10 announcements anyway. If they are not discrete from a routing policy
perspective, then, one announcement is possible. In the case where the
routing policies are distinct, expansion in on network will require additional
announcement(s) from that network specifically. In the case where the
routing policies are not distinct, the additional space could be aggregated
across the networks, at least theoretically.

> I don't imagine this will have much of an impact on IPv4 one way or
> another simply because v4 depletion moots the issue. However, we carry
> this problem with us to IPv6 so if a game reveals substantive problem
> scenarios then it's probably worth fixing.

Not so much. The IPv6 MDN policy is already significantly more permissive
than the IPv4 policy.


More information about the ARIN-PPML mailing list