[arin-ppml] IPv6 Non-connected networks

William Herrin bill at herrin.us
Thu Feb 4 14:42:15 EST 2010

On Tue, Jan 19, 2010 at 6:25 PM, David Farmer <farmer at umn.edu> wrote:
> At the Dearborn meeting I heard a lot of people say that ARIN shouldn't
> dictate routing policy.  I personally would find it hard to reconcile that
> stance with the idea of ARIN assigning non-connected /48s from a separate
> block. At least without an RFC defining centrally assignable ULA addressing,
> then ARIN would not be defining it, the IETF would be, ARIN would only be
> implementing something defined by the IETF.

Hi David,

When ARIN assigns two different classes of use interspersed within the
same address block, functionally they dictate that however service
providers treat the one use, they will treat the other the same. If
one use must be carried on the Internet by reasonable ISPs then ARIN
has dictated that the other use will be carried too. In practical
effect, ARIN has set the routing policy for that second class of use.

Two obvious examples of this would be:

Assigning /22's adjacent to /16's. ARIN's practice dictates that the
/16's will be disaggregable by the assignee to /22 for TE purposes as

Assigning multihomed and non-multihomed prefixes adjacent to each
other. ARIN's practice dictates that the ISPs will not distinguish
between routes announced by multihomed and single-homed entities.

When folks say "ARIN shouldn't dictate routing policy," what they mean
is, "ARIN should allocate address in a manner which makes it
technically practical for ISPs to hang their own routing policies off
the specific, major classes of use."

Some vectors which create the major classes of use include:

Aggregable (traffic engineering, single-homed downstream entities) /
non-aggregable (distinct multihomed entitiy)
Big / Small
Residential / commercial / government
My legal jurisdiction (aka country) / other jurisdiction
Internet-connected / not internet connected
Pay me / don't pay me

Perhaps others can suggest some additional IP address use vectors
which draw an important distinction with respect to desirable routing

> So what is the direction the community wants to go for IPv6 non-connected
> networks?

Published unique pool so that ISPs can assure that the non-connected
networks stay non-connected, even if Jim's Bait and Network Services
gets bribed to introduce a route.

Bill Herrin

William D. Herrin ................ herrin at dirtside.com  bill at herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004

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