North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: Requesting P.I. Space from ARIN - latest issues?

  • From: Joe Abley
  • Date: Tue Oct 11 12:04:23 2005

On 11-Oct-2005, at 11:33, Justin M. Streiner wrote:

On Tue, 11 Oct 2005, [email protected] wrote:

1) I meet the Multihoming requirement, which means I can get a block as
small as a /22, which is about right for my needs. Are there still any
concerns about networks (as Verio and Sprint have done in the past)
filtering out longer prefixes, and if so, does it depend on whether it;s
former class A, B, C or swamp space? I know when I got my current block
from my upstream, I had to make sure I got swamp space, because the former
class B block they initially allocated to me wouldn't have made it past
Verio's filters at that time.
Most if not all of the /8s that get assigned to ARIN have a prescribed minimum allocation size. How rigorously that is followed is another story :-)
I believe it is followed rigourously for new assignments, and that / 22 assignments are made from a range of addresses whose minimum allocation size is /22 (or longer).

ISPs who filter based on prefix length according to RIR minimum allocation sizes should not block a route based on such an assignment, assuming their filters are up-to-date.

Whether or not any particular prefix is blocked is best determined experimentally (e.g. feed a box with two interface addresses from different ranges a list of hosts to ping at a polite, low frequency, and compare the results sourced from each address).

I have had dealings with many ISPs who have announced blocks based on fairly long-prefix assignments from RIRs, following policies such as ARIN's multi-homing assignment policy, and I haven't heard of any substantial problems due to the prefix length. James' MMV, of course.

I don't think you can specifically request that ARIN assign you space out of the swamp these days.
You can request anything you like. Whether it makes a difference is another thing entirely :-)


Joe