[arin-ppml] ARIN Multiple Discrete Networks Policy

Jeff Wheeler jsw at inconcepts.biz
Mon Oct 3 18:58:31 EDT 2011

> On Sat, Oct 01, 2011 at 08:17:36 EDT 2011, John Curran wrote:
> Incorrect. If an organization has a compelling reason (along the lines
> of the provided examples) for creating multiple discrete networks and
> desires to request new or additional address space under a single
> Organization ID, then it can request space under the MDN criteria.

Having re-subscribed to this list after reviewing the posts on this
thread, I'll simply reiterate my probably well-known opinion that the
biggest problem with the RIRs is they claim not to care about routing
when it's convenient for them, yet every allocation action they take
impacts routing, and many policies, in place for over a decade, were
crafted for the specific purpose of routing table efficiency.  For
example, it was common for ISPs to receive a /20 but have a /19
reserved, so they would have an allocation that was justified but also
be able to get it accepted by the SprintLink filters in place during
the mid-90s and carried on by some other networks.

There has never been any reason to reserve additional address space,
beyond what is justified by an application, except to conserve routing
table resources.  To say otherwise is idiotic.  So to say the RIRs
don't involve themselves in routing policy is the biggest,
longest-running lie in the game.  It may be a convenient lie when you
want to interpret policy just so, but the membership have taken
routing policy into consideration for a very long time.

If you want to go on pretending that this is true, go right ahead.  On
the other hand, you could make yourself the guy that acknowledges the
above truth and directs his energy into doing something constructive.
A good start would be to acknowledge that yes, RIR policy does indeed
take routing policy into consideration; and it may be a good idea to
do this in more ways.

There is a huge amount of routing table pollution that simply comes
from stupidity -- ISPs who announce every /24 out of their /19 because
they don't understand how to do it another way, those who decide this
is a good means of inbound traffic-engineering, and so on.  That could
have, and should have, been addressed by the RIRs years ago but we're
way past that point now.

I think Richard's multiple discrete networks concern is a very small
contributor to deaggregation / DFZ pollution, and it really can't
compete with pollution created by sheer stupidity; so I honestly can't
bring myself to care about this particular issue, other than to state
clearly that the MDN language should apply to the examples he
describes as it will not significantly contribute to IPv4 exhaustion
(like, say, handing Verizon Wireless 75% of a /8 years ago when there
is no possible way such allocation could have been justified) but it
does reduce routing table pollution.

The sooner RIRs get off the "we don't care about routing" company line
and realize that, in an IPv6 world, managing DFZ bloat is the only way
they can contribute anything useful, the better off we will all be.

The old thinking that vendors can ship new linecards with more FIB
capacity whenever we need them to is foolish.  Yes, they can; and then
you have to upgrade every DFZ box in your network.  More FIB
contributes substantially to power draw and heat production, which
limits router density and increases OpEx.  If you have to do that
upgrade cycle because you are out of FIB before your platforms are
otherwise functionally obsolete, you have to lay out capital dollars
and pray that you can still sell your old cards on the used market.
None of these things are good.  And yet, the way things are evolving,
the current generation of DFZ routers will probably not have
sufficient FIB for the IPv6 DFZ within a few years.

You *can* fix the stupidity problem.  In fact, when the small
multi-homed network (2002-3?) policy was implemented, ARIN allocated
these networks from special blocks in an effort to avoid having
recipients of a /22 or similar from being unable to use their
allocations.  Does ARIN guarantee that an allocation will be
globally-reachable?  No, of course not.  But ARIN absolutely does make
efforts in this area, even in the absence of specific policy language,
simply by implementing policy in a way that is sensible -- with
consideration given to routing policy.

Jeff S Wheeler <jsw at inconcepts.biz>
Sr Network Operator  /  Innovative Network Concepts

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