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

Tue Oct 11 15:59:58 UTC 2005

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

> On Tue, 11 Oct 2005, up at 3.am 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